oh momma. a lot of modifications and it appears to be working. w00t.

3 files changed, 3348 insertions, 1337 deletions

diff --git a/nexgb/cookie.go b/nexgb/cookie.go
new file mode 100644
index 0000000..502ccbf
--- /dev/null
+++ b/nexgb/cookie.go
@@ -0,0 +1,111 @@
+package xgb
+
+import (
+	"errors"
+)
+
+type cookie struct {
+	Sequence        uint16
+	replyChan chan []byte
+	errorChan chan error
+	pingChan chan bool
+}
+
+func (c *Conn) newCookie(checked, reply bool) cookie {
+	cookie := cookie{
+		Sequence: c.newSequenceId(),
+		replyChan: nil,
+		errorChan: nil,
+		pingChan: nil,
+	}
+
+	// There are four different kinds of cookies:
+	// Checked requests with replies get a reply channel and an error channel.
+	// Unchecked requests with replies get a reply channel and a ping channel.
+	// Checked requests w/o replies get a ping channel and an error channel.
+	// Unchecked requests w/o replies get no channels.
+	// The reply channel is used to send reply data.
+	// The error channel is used to send error data.
+	// The ping channel is used when one of the 'reply' or 'error' channels
+	// is missing but the other is present. The ping channel is way to force
+	// the blocking to stop and basically say "the error has been received
+	// in the main event loop" (when the ping channel is coupled with a reply
+	// channel) or "the request you made that has no reply was successful"
+	// (when the ping channel is coupled with an error channel).
+	if checked {
+		cookie.errorChan = make(chan error, 1)
+		if !reply {
+			cookie.pingChan = make(chan bool, 1)
+		}
+	}
+	if reply {
+		cookie.replyChan = make(chan []byte, 1)
+		if !checked {
+			cookie.pingChan = make(chan bool, 1)
+		}
+	}
+
+	return cookie
+}
+
+func (c cookie) reply() ([]byte, error) {
+	// checked
+	if c.errorChan != nil {
+		return c.replyChecked()
+	}
+	return c.replyUnchecked()
+}
+
+func (c cookie) replyChecked() ([]byte, error) {
+	if c.replyChan == nil {
+		return nil, errors.New("Cannot call 'replyChecked' on a cookie that " +
+			"is not expecting a *reply* or an error.")
+	}
+	if c.errorChan == nil {
+		return nil, errors.New("Cannot call 'replyChecked' on a cookie that " +
+			"is not expecting a reply or an *error*.")
+	}
+
+	select {
+	case reply := <-c.replyChan:
+		return reply, nil
+	case err := <-c.errorChan:
+		return nil, err
+	}
+	panic("unreachable")
+}
+
+func (c cookie) replyUnchecked() ([]byte, error) {
+	if c.replyChan == nil {
+		return nil, errors.New("Cannot call 'replyUnchecked' on a cookie " +
+			"that is not expecting a *reply*.")
+	}
+
+	select {
+	case reply := <-c.replyChan:
+		return reply, nil
+	case <-c.pingChan:
+		return nil, nil
+	}
+	panic("unreachable")
+}
+
+func (c cookie) Check() error {
+	if c.replyChan != nil {
+		return errors.New("Cannot call 'Check' on a cookie that is " +
+			"expecting a *reply*. Use 'Reply' instead.")
+	}
+	if c.errorChan == nil {
+		return errors.New("Cannot call 'Check' on a cookie that is " +
+			"not expecting a possible *error*.")
+	}
+
+	select {
+	case err := <-c.errorChan:
+		return err
+	case <-c.pingChan:
+		return nil
+	}
+	panic("unreachable")
+}
+
diff --git a/nexgb/xgb.go b/nexgb/xgb.go
index 1a4ada1..b453427 100644
--- a/nexgb/xgb.go
+++ b/nexgb/xgb.go
@@ -25,27 +25,18 @@ const (
 type Conn struct {
 	host          string
 	conn          net.Conn
-	nextCookie    uint16
-	cookies       map[uint16]*Cookie
-	events        queue
 	err           error
 	display       string
 	defaultScreen int
-	scratch       [32]byte
 	Setup         SetupInfo
 	extensions    map[string]byte
 
-	requestChan       chan *Request
-	requestCookieChan chan *Cookie
-	replyChan         chan bool
-	eventChan         chan bool
-	errorChan         chan bool
-
+	eventChan         chan eventOrError
+	cookieChan chan cookie
 	xidChan chan xid
-	newIdLock   sync.Mutex
-	writeLock   sync.Mutex
-	dequeueLock sync.Mutex
-	cookieLock  sync.Mutex
+	seqChan chan uint16
+	reqChan chan *request
+
 	extLock     sync.Mutex
 }
 
@@ -75,16 +66,18 @@ func NewConnDisplay(display string) (*Conn, error) {
 		return nil, err
 	}
 
-	conn.xidChan = make(chan xid, 5)
-	go conn.generateXids()
-
-	conn.nextCookie = 1
-	conn.cookies = make(map[uint16]*Cookie)
-	conn.events = queue{make([][]byte, 100), 0, 0}
 	conn.extensions = make(map[string]byte)
 
-	conn.newReadChannels()
-	conn.newRequestChannels()
+	conn.cookieChan = make(chan cookie, 100)
+	conn.xidChan = make(chan xid, 5)
+	conn.seqChan = make(chan uint16, 20)
+	conn.reqChan = make(chan *request, 100)
+	conn.eventChan = make(chan eventOrError, 100)
+
+	go conn.generateXIds()
+	go conn.generateSeqIds()
+	go conn.sendRequests()
+	go conn.readResponses()
 
 	return conn, nil
 }
@@ -97,43 +90,11 @@ func (c *Conn) Close() {
 // Id is used for all X identifiers, such as windows, pixmaps, and GCs.
 type Id uint32
 
-// Request is used to abstract the difference between a request
-// that expects a reply and a request that doesn't expect a reply.
-type Request struct {
-	buf        []byte
-	cookieChan chan *Cookie
-}
-
-func newRequest(buf []byte, needsReply bool) *Request {
-	req := &Request{
-		buf:        buf,
-		cookieChan: nil,
-	}
-	if needsReply {
-		req.cookieChan = make(chan *Cookie)
-	}
-	return req
-}
-
-// Cookies are the sequence numbers used to pair replies up with their requests
-type Cookie struct {
-	id        uint16
-	replyChan chan []byte
-	errorChan chan error
-}
-
-func newCookie(id uint16) *Cookie {
-	return &Cookie{
-		id:        id,
-		replyChan: make(chan []byte, 1),
-		errorChan: make(chan error, 1),
-	}
-}
-
 // Event is an interface that can contain any of the events returned by the
 // server. Use a type assertion switch to extract the Event structs.
 type Event interface {
 	ImplementsEvent()
+	Bytes() []byte
 }
 
 // newEventFuncs is a map from event numbers to functions that create
@@ -153,6 +114,10 @@ type Error interface {
 // the corresponding error.
 var newErrorFuncs = map[int]func(buf []byte) Error{}
 
+// eventOrError corresponds to values that can be either an event or an
+// error.
+type eventOrError interface{}
+
 // NewID generates a new unused ID for use with requests like CreateWindow.
 // If no new ids can be generated, the id returned is 0 and error is non-nil.
 func (c *Conn) NewId() (Id, error) {
@@ -164,7 +129,7 @@ func (c *Conn) NewId() (Id, error) {
 }
 
 // xid encapsulates a resource identifier being sent over the Conn.xidChan
-// channel. If no new resource id can be generated, id is set to -1 and a
+// channel. If no new resource id can be generated, id is set to 0 and a
 // non-nil error is set in xid.err.
 type xid struct {
 	id Id
@@ -174,7 +139,24 @@ type xid struct {
 // generateXids sends new Ids down the channel for NewId to use.
 // This needs to be updated to use the XC Misc extension once we run out of
 // new ids.
-func (conn *Conn) generateXids() {
+// Thanks to libxcb/src/xcb_xid.c. This code is greatly inspired by it.
+func (conn *Conn) generateXIds() {
+	// This requires some explanation. From the horse's mouth:
+	// "The resource-id-mask contains a single contiguous set of bits (at least 
+	// 18).  The client allocates resource IDs for types WINDOW, PIXMAP, 
+	// CURSOR, FONT, GCONTEXT, and COLORMAP by choosing a value with only some 
+	// subset of these bits set and ORing it with resource-id-base. Only values 
+	// constructed in this way can be used to name newly created resources over 
+	// this connection."
+	// So for example (using 8 bit integers), the mask might look like:
+	// 00111000
+	// So that valid values would be 00101000, 00110000, 00001000, and so on.
+	// Thus, the idea is to increment it by the place of the last least
+	// significant '1'. In this case, that value would be 00001000. To get
+	// that value, we can AND the original mask with its two's complement:
+	// 00111000 & 11001000 = 00001000.
+	// And we use that value to increment the last resource id to get a new one.
+	// (And then, of course, we OR it with resource-id-base.)
 	inc := conn.Setup.ResourceIdMask & -conn.Setup.ResourceIdMask
 	max := conn.Setup.ResourceIdMask
 	last := uint32(0)
@@ -196,210 +178,236 @@ func (conn *Conn) generateXids() {
 	}
 }
 
-// RegisterExtension adds the respective extension's major op code to
-// the extensions map.
-func (c *Conn) RegisterExtension(name string) error {
-	nameUpper := strings.ToUpper(name)
-	reply, err := c.QueryExtension(uint16(len(nameUpper)), nameUpper)
-
-	switch {
-	case err != nil:
-		return err
-	case !reply.Present:
-		return errors.New(fmt.Sprintf("No extension named '%s' is present.",
-			nameUpper))
-	}
-
-	c.extLock.Lock()
-	c.extensions[nameUpper] = reply.MajorOpcode
-	c.extLock.Unlock()
-
-	return nil
-}
-
-// A simple queue used to stow away events.
-type queue struct {
-	data [][]byte
-	a, b int
+// newSeqId fetches the next sequence id from the Conn.seqChan channel.
+func (c *Conn) newSequenceId() uint16 {
+	return <-c.seqChan
 }
 
-func (q *queue) queue(item []byte) {
-	if q.b == len(q.data) {
-		if q.a > 0 {
-			copy(q.data, q.data[q.a:q.b])
-			q.a, q.b = 0, q.b-q.a
+// generateSeqIds returns new sequence ids.
+// A sequence id is generated for *every* request. It's the identifier used
+// to match up replies with requests.
+// Since sequence ids can only be 16 bit integers we start over at zero when it 
+// comes time to wrap.
+// FIXME: 65,536 requests without replies cannot be made in a single sequence.
+func (c *Conn) generateSeqIds() {
+	seqid := uint16(1)
+	for {
+		c.seqChan <- seqid
+		if seqid == uint16((1 << 16) - 1) {
+			seqid = 0
 		} else {
-			newData := make([][]byte, (len(q.data)*3)/2)
-			copy(newData, q.data)
-			q.data = newData
+			seqid++
 		}
 	}
-	q.data[q.b] = item
-	q.b++
 }
 
-func (q *queue) dequeue(c *Conn) []byte {
-	c.dequeueLock.Lock()
-	defer c.dequeueLock.Unlock()
+// request encapsulates a buffer of raw bytes (containing the request data)
+// and a cookie, which when combined represents a single request.
+// The cookie is used to match up the reply/error.
+type request struct {
+	buf []byte
+	cookie cookie
+}
+
+// newRequest takes the bytes an a cookie, constructs a request type,
+// and sends it over the Conn.reqChan channel. It then returns the cookie
+// (for convenience).
+func (c *Conn) newRequest(buf []byte, cookie cookie) {
+	c.reqChan <- &request{buf: buf, cookie: cookie}
+}
 
-	if q.a < q.b {
-		item := q.data[q.a]
-		q.a++
-		return item
+// sendRequests is run as a single goroutine that takes requests and writes
+// the bytes to the wire and adds the cookie to the cookie queue.
+func (c *Conn) sendRequests() {
+	for req := range c.reqChan {
+		c.cookieChan <- req.cookie
+		if _, err := c.conn.Write(req.buf); err != nil {
+			fmt.Fprintf(os.Stderr, "x protocol write error: %s\n", err)
+			close(c.reqChan)
+			return
+		}
 	}
-	return nil
 }
 
-// newWriteChan creates the channel required for writing to the net.Conn.
-func (c *Conn) newRequestChannels() {
-	c.requestChan = make(chan *Request, writeBuffer)
-	c.requestCookieChan = make(chan *Cookie, 1)
+// readResponses is a goroutine that reads events, errors and
+// replies off the wire.
+// When an event is read, it is always added to the event channel.
+// When an error is read, if it corresponds to an existing checked cookie,
+// it is sent to that cookie's error channel. Otherwise it is added to the
+// event channel.
+// When a reply is read, it is added to the corresponding cookie's reply
+// channel. (It is an error if no such cookie exists in this case.)
+// Finally, cookies that came "before" this reply are always cleaned up.
+func (c *Conn) readResponses() {
+	var (
+		err Error
+		event Event
+		seq uint16
+		replyBytes []byte
+	)
 
-	go func() {
-		for request := range c.requestChan {
-			cookieNum := c.nextCookie
-			c.nextCookie++
+	buf := make([]byte, 32)
+	for {
+		err, event, seq = nil, nil, 0
 
-			if request.cookieChan != nil {
-				cookie := newCookie(cookieNum)
-				c.cookies[cookieNum] = cookie
-				request.cookieChan <- cookie
-			}
-			if _, err := c.conn.Write(request.buf); err != nil {
-				fmt.Fprintf(os.Stderr, "x protocol write error: %s\n", err)
-				close(c.requestChan)
-				return
-			}
+		if _, err := io.ReadFull(c.conn, buf); err != nil {
+			fmt.Fprintf(os.Stderr, "x protocol read error: %s\n", err)
+			close(c.eventChan)
+			break
 		}
-	}()
-}
 
-// request is a buffered write to net.Conn.
-func (c *Conn) request(buf []byte, needsReply bool) *Cookie {
-	req := newRequest(buf, needsReply)
-	c.requestChan <- req
+		switch buf[0] {
+		case 0: // This is an error
+			// Use the constructor function for this error (that is auto
+			// generated) by looking it up by the error number.
+			err = newErrorFuncs[int(buf[1])](buf)
+			seq = err.SequenceId()
 
-	if req.cookieChan != nil {
-		cookie := <-req.cookieChan
-		close(req.cookieChan)
-		return cookie
-	}
-	return nil
-}
+			// This error is either sent to the event channel or a specific
+			// cookie's error channel below.
+		case 1: // This is a reply
+			seq = Get16(buf[2:])
 
-func (c *Conn) sendRequest(needsReply bool, bufs ...[]byte) *Cookie {
-	if len(bufs) == 1 {
-		return c.request(bufs[0], needsReply)
-	}
-
-	total := make([]byte, 0)
-	for _, buf := range bufs {
-		total = append(total, buf...)
-	}
-	return c.request(total, needsReply)
-}
+			// check to see if this reply has more bytes to be read
+			size := Get32(buf[4:])
+			if size > 0 {
+				byteCount := 32 + size * 4
+				biggerBuf := make([]byte, byteCount)
+				copy(biggerBuf[:32], buf)
+				if _, err := io.ReadFull(c.conn, biggerBuf[32:]); err != nil {
+					fmt.Fprintf(os.Stderr, "x protocol read error: %s\n", err)
+					close(c.eventChan)
+					break
+				}
+				replyBytes = biggerBuf
+			} else {
+				replyBytes = buf
+			}
 
-func (c *Conn) newReadChannels() {
-	c.eventChan = make(chan bool, readBuffer)
+			// This reply is sent to its corresponding cookie below.
+		default: // This is an event
+			// Use the constructor function for this event (like for errors,
+			// and is also auto generated) by looking it up by the event number.
+			// Note that we AND the event number with 127 so that we ignore
+			// the most significant bit (which is set when it was sent from
+			// a SendEvent request).
+			event = newEventFuncs[int(buf[0] & 127)](buf)
+			// seq = event.SequenceId() // 0 for KeymapNotify 
 
-	onError := func() {
-		panic("read error")
-	}
+			// Put the event into the queue.
+			c.eventChan <- event
 
-	go func() {
-		for {
-			buf := make([]byte, 32)
-			if _, err := io.ReadFull(c.conn, buf); err != nil {
-				fmt.Fprintf(os.Stderr, "x protocol read error: %s\n", err)
-				onError()
-				return
-			}
+			// No more processing for events.
+			continue
 
-			switch buf[0] {
-			case 0:
-				// err := &Error{ 
-					// Detail: buf[1], 
-					// Cookie: uint16(get16(buf[2:])), 
-					// Id:     Id(get32(buf[4:])), 
-					// Minor:  get16(buf[8:]), 
-					// Major:  buf[10], 
+			// If this was a KeymapNotify event, then we don't do any more
+			// processing since we don't have any sequence id.
+			// if event != nil { 
+				// if _, ok := event.(KeymapNotifyEvent); ok { 
+					// continue 
 				// } 
-				err := newErrorFuncs[int(buf[1])](buf)
-				if cookie, ok := c.cookies[err.SequenceId()]; ok {
-					cookie.errorChan <- err
-				} else {
-					fmt.Fprintf(os.Stderr, "x protocol error: %s\n", err)
-				}
-			case 1:
-				seq := uint16(Get16(buf[2:]))
-				if _, ok := c.cookies[seq]; !ok {
-					continue
-				}
+			// } 
+		}
 
-				size := Get32(buf[4:])
-				if size > 0 {
-					bigbuf := make([]byte, 32+size*4, 32+size*4)
-					copy(bigbuf[0:32], buf)
-					if _, err := io.ReadFull(c.conn, bigbuf[32:]); err != nil {
+		// At this point, we have a sequence number and we're either
+		// processing an error or a reply, which are both responses to
+		// requests. So all we have to do is find the cookie corresponding
+		// to this error/reply, and send the appropriate data to it.
+		// In doing so, we make sure that any cookies that came before it
+		// are marked as successful if they are void and checked.
+		// If there's a cookie that requires a reply that is before this
+		// reply, then something is wrong.
+		for cookie := range c.cookieChan {
+			// This is the cookie we're looking for. Process and break.
+			if cookie.Sequence == seq {
+				if err != nil { // this is an error to a request
+					// synchronous processing
+					if cookie.errorChan != nil {
+						cookie.errorChan <- err
+					} else { // asynchronous processing
+						c.eventChan <- err
+					}
+				} else { // this is a reply
+					if cookie.replyChan == nil {
 						fmt.Fprintf(os.Stderr,
-							"x protocol read error: %s\n", err)
-						onError()
-						return
+							"Reply with sequence id %d does not have a " +
+							"cookie with a valid reply channel.\n", seq)
+					} else {
+						cookie.replyChan <- replyBytes
 					}
-					c.cookies[seq].replyChan <- bigbuf
-				} else {
-					c.cookies[seq].replyChan <- buf
-				}
-			default:
-				c.events.queue(buf)
-				select {
-				case c.eventChan <- true:
-				default:
 				}
+				break
+			}
+
+			switch {
+			// Checked requests with replies
+			case cookie.replyChan != nil && cookie.errorChan != nil:
+				fmt.Fprintf(os.Stderr,
+					"Found cookie with sequence id %d that is expecting a " +
+					"reply but will never get it.\n", cookie.Sequence)
+			// Unchecked requests with replies
+			case cookie.replyChan != nil && cookie.pingChan != nil:
+				cookie.pingChan <- true
+			// Checked requests without replies
+			case cookie.pingChan != nil && cookie.errorChan != nil:
+				cookie.pingChan <- true
+			// Unchecked requests without replies don't have any channels,
+			// so we can't do anything with them except let them pass by.
 			}
 		}
-	}()
+	}
 }
 
-func (c *Conn) waitForReply(cookie *Cookie) ([]byte, error) {
-	if cookie == nil {
-		panic("nil cookie")
-	}
-	if _, ok := c.cookies[cookie.id]; !ok {
-		panic("waiting for a cookie that will never come")
-	}
-	select {
-	case reply := <-cookie.replyChan:
-		return reply, nil
-	case err := <-cookie.errorChan:
-		return nil, err
+// processEventOrError takes an eventOrError, type switches on it,
+// and returns it in Go idiomatic style.
+func processEventOrError(everr eventOrError) (Event, Error) {
+	switch ee := everr.(type) {
+	case Event:
+		return ee, nil
+	case Error:
+		return nil, ee
+	default:
+		fmt.Fprintf(os.Stderr, "Invalid event/error type: %T\n", everr)
 	}
 	panic("unreachable")
 }
 
 // WaitForEvent returns the next event from the server.
 // It will block until an event is available.
-func (c *Conn) WaitForEvent() (Event, error) {
-	for {
-		if reply := c.events.dequeue(c); reply != nil {
-			evCode := reply[0] & 0x7f
-			return newEventFuncs[int(evCode)](reply), nil
-		}
-		if !<-c.eventChan {
-			return nil, errors.New("Event channel has been closed.")
-		}
+func (c *Conn) WaitForEvent() (Event, Error) {
+	return processEventOrError(<-c.eventChan)
+}
+
+// PollForEvent returns the next event from the server if one is available in 
+// the internal queue.
+// It will not block.
+func (c *Conn) PollForEvent() (Event, Error) {
+	select {
+	case everr := <-c.eventChan:
+		return processEventOrError(everr)
+	default:
+		return nil, nil
 	}
 	panic("unreachable")
 }
 
-// PollForEvent returns the next event from the server if one is available in the internal queue.
-// It will not read from the connection, so you must call WaitForEvent to receive new events.
-// Only use this function to empty the queue without blocking.
-func (c *Conn) PollForEvent() (Event, error) {
-	if reply := c.events.dequeue(c); reply != nil {
-		evCode := reply[0] & 0x7f
-		return newEventFuncs[int(evCode)](reply), nil
+// RegisterExtension adds the respective extension's major op code to
+// the extensions map.
+func (c *Conn) RegisterExtension(name string) error {
+	nameUpper := strings.ToUpper(name)
+	reply, err := c.QueryExtension(uint16(len(nameUpper)), nameUpper).Reply()
+
+	switch {
+	case err != nil:
+		return err
+	case !reply.Present:
+		return errors.New(fmt.Sprintf("No extension named '%s' is present.",
+			nameUpper))
 	}
-	return nil, nil
-}
 
+	c.extLock.Lock()
+	c.extensions[nameUpper] = reply.MajorOpcode
+	c.extLock.Unlock()
+
+	return nil
+}
diff --git a/nexgb/xproto.go b/nexgb/xproto.go
index 3317b51..d56f0a1 100644
--- a/nexgb/xproto.go
+++ b/nexgb/xproto.go
@@ -1,10 +1,22 @@
 package xgb
 
 /*
-	This file was generated by xproto.xml on May 3 2012 12:48:47am EDT.
+	This file was generated by xproto.xml on May 5 2012 2:50:11am EDT.
 	This file is automatically generated. Edit at your peril!
 */
 
+// Skipping definition for base type 'Int8'
+
+// Skipping definition for base type 'Card16'
+
+// Skipping definition for base type 'Char'
+
+// Skipping definition for base type 'Card32'
+
+// Skipping definition for base type 'Double'
+
+// Skipping definition for base type 'Bool'
+
 // Skipping definition for base type 'Float'
 
 // Skipping definition for base type 'Id'
@@ -19,18 +31,6 @@ package xgb
 
 // Skipping definition for base type 'Byte'
 
-// Skipping definition for base type 'Int8'
-
-// Skipping definition for base type 'Card16'
-
-// Skipping definition for base type 'Char'
-
-// Skipping definition for base type 'Card32'
-
-// Skipping definition for base type 'Double'
-
-// Skipping definition for base type 'Bool'
-
 const (
 	VisualClassStaticGray  = 0
 	VisualClassGrayScale   = 1
@@ -2727,6 +2727,10 @@ func (v KeyPressEvent) Bytes() []byte {
 
 func (v KeyPressEvent) ImplementsEvent() {}
 
+func (v KeyPressEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[2] = NewKeyPressEvent
 }
@@ -2857,6 +2861,10 @@ func (v ButtonPressEvent) Bytes() []byte {
 
 func (v ButtonPressEvent) ImplementsEvent() {}
 
+func (v ButtonPressEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[4] = NewButtonPressEvent
 }
@@ -2987,6 +2995,10 @@ func (v MotionNotifyEvent) Bytes() []byte {
 
 func (v MotionNotifyEvent) ImplementsEvent() {}
 
+func (v MotionNotifyEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[6] = NewMotionNotifyEvent
 }
@@ -3111,6 +3123,10 @@ func (v EnterNotifyEvent) Bytes() []byte {
 
 func (v EnterNotifyEvent) ImplementsEvent() {}
 
+func (v EnterNotifyEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[7] = NewEnterNotifyEvent
 }
@@ -3177,6 +3193,10 @@ func (v FocusInEvent) Bytes() []byte {
 
 func (v FocusInEvent) ImplementsEvent() {}
 
+func (v FocusInEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[9] = NewFocusInEvent
 }
@@ -3219,6 +3239,10 @@ func (v KeymapNotifyEvent) Bytes() []byte {
 
 func (v KeymapNotifyEvent) ImplementsEvent() {}
 
+func (v KeymapNotifyEvent) SequenceId() uint16 {
+	return uint16(0)
+}
+
 func init() {
 	newEventFuncs[11] = NewKeymapNotifyEvent
 }
@@ -3311,6 +3335,10 @@ func (v ExposeEvent) Bytes() []byte {
 
 func (v ExposeEvent) ImplementsEvent() {}
 
+func (v ExposeEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[12] = NewExposeEvent
 }
@@ -3417,6 +3445,10 @@ func (v GraphicsExposureEvent) Bytes() []byte {
 
 func (v GraphicsExposureEvent) ImplementsEvent() {}
 
+func (v GraphicsExposureEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[13] = NewGraphicsExposureEvent
 }
@@ -3488,6 +3520,10 @@ func (v NoExposureEvent) Bytes() []byte {
 
 func (v NoExposureEvent) ImplementsEvent() {}
 
+func (v NoExposureEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[14] = NewNoExposureEvent
 }
@@ -3552,6 +3588,10 @@ func (v VisibilityNotifyEvent) Bytes() []byte {
 
 func (v VisibilityNotifyEvent) ImplementsEvent() {}
 
+func (v VisibilityNotifyEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[15] = NewVisibilityNotifyEvent
 }
@@ -3666,6 +3706,10 @@ func (v CreateNotifyEvent) Bytes() []byte {
 
 func (v CreateNotifyEvent) ImplementsEvent() {}
 
+func (v CreateNotifyEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[16] = NewCreateNotifyEvent
 }
@@ -3725,6 +3769,10 @@ func (v DestroyNotifyEvent) Bytes() []byte {
 
 func (v DestroyNotifyEvent) ImplementsEvent() {}
 
+func (v DestroyNotifyEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[17] = NewDestroyNotifyEvent
 }
@@ -3804,6 +3852,10 @@ func (v UnmapNotifyEvent) Bytes() []byte {
 
 func (v UnmapNotifyEvent) ImplementsEvent() {}
 
+func (v UnmapNotifyEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[18] = NewUnmapNotifyEvent
 }
@@ -3883,6 +3935,10 @@ func (v MapNotifyEvent) Bytes() []byte {
 
 func (v MapNotifyEvent) ImplementsEvent() {}
 
+func (v MapNotifyEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[19] = NewMapNotifyEvent
 }
@@ -3942,6 +3998,10 @@ func (v MapRequestEvent) Bytes() []byte {
 
 func (v MapRequestEvent) ImplementsEvent() {}
 
+func (v MapRequestEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[20] = NewMapRequestEvent
 }
@@ -4042,6 +4102,10 @@ func (v ReparentNotifyEvent) Bytes() []byte {
 
 func (v ReparentNotifyEvent) ImplementsEvent() {}
 
+func (v ReparentNotifyEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[21] = NewReparentNotifyEvent
 }
@@ -4163,6 +4227,10 @@ func (v ConfigureNotifyEvent) Bytes() []byte {
 
 func (v ConfigureNotifyEvent) ImplementsEvent() {}
 
+func (v ConfigureNotifyEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[22] = NewConfigureNotifyEvent
 }
@@ -4273,6 +4341,10 @@ func (v ConfigureRequestEvent) Bytes() []byte {
 
 func (v ConfigureRequestEvent) ImplementsEvent() {}
 
+func (v ConfigureRequestEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[23] = NewConfigureRequestEvent
 }
@@ -4346,6 +4418,10 @@ func (v GravityNotifyEvent) Bytes() []byte {
 
 func (v GravityNotifyEvent) ImplementsEvent() {}
 
+func (v GravityNotifyEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[24] = NewGravityNotifyEvent
 }
@@ -4412,6 +4488,10 @@ func (v ResizeRequestEvent) Bytes() []byte {
 
 func (v ResizeRequestEvent) ImplementsEvent() {}
 
+func (v ResizeRequestEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[25] = NewResizeRequestEvent
 }
@@ -4488,6 +4568,10 @@ func (v CirculateNotifyEvent) Bytes() []byte {
 
 func (v CirculateNotifyEvent) ImplementsEvent() {}
 
+func (v CirculateNotifyEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[26] = NewCirculateNotifyEvent
 }
@@ -4566,6 +4650,10 @@ func (v PropertyNotifyEvent) Bytes() []byte {
 
 func (v PropertyNotifyEvent) ImplementsEvent() {}
 
+func (v PropertyNotifyEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[28] = NewPropertyNotifyEvent
 }
@@ -4632,6 +4720,10 @@ func (v SelectionClearEvent) Bytes() []byte {
 
 func (v SelectionClearEvent) ImplementsEvent() {}
 
+func (v SelectionClearEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[29] = NewSelectionClearEvent
 }
@@ -4719,6 +4811,10 @@ func (v SelectionRequestEvent) Bytes() []byte {
 
 func (v SelectionRequestEvent) ImplementsEvent() {}
 
+func (v SelectionRequestEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[30] = NewSelectionRequestEvent
 }
@@ -4799,6 +4895,10 @@ func (v SelectionNotifyEvent) Bytes() []byte {
 
 func (v SelectionNotifyEvent) ImplementsEvent() {}
 
+func (v SelectionNotifyEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[31] = NewSelectionNotifyEvent
 }
@@ -4885,6 +4985,10 @@ func (v ColormapNotifyEvent) Bytes() []byte {
 
 func (v ColormapNotifyEvent) ImplementsEvent() {}
 
+func (v ColormapNotifyEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[32] = NewColormapNotifyEvent
 }
@@ -4956,6 +5060,10 @@ func (v ClientMessageEvent) Bytes() []byte {
 
 func (v ClientMessageEvent) ImplementsEvent() {}
 
+func (v ClientMessageEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[33] = NewClientMessageEvent
 }
@@ -5027,6 +5135,10 @@ func (v MappingNotifyEvent) Bytes() []byte {
 
 func (v MappingNotifyEvent) ImplementsEvent() {}
 
+func (v MappingNotifyEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[34] = NewMappingNotifyEvent
 }
@@ -5047,6 +5159,10 @@ func (v KeyReleaseEvent) Bytes() []byte {
 
 func (v KeyReleaseEvent) ImplementsEvent() {}
 
+func (v KeyReleaseEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[3] = NewKeyReleaseEvent
 }
@@ -5067,6 +5183,10 @@ func (v ButtonReleaseEvent) Bytes() []byte {
 
 func (v ButtonReleaseEvent) ImplementsEvent() {}
 
+func (v ButtonReleaseEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[5] = NewButtonReleaseEvent
 }
@@ -5087,6 +5207,10 @@ func (v LeaveNotifyEvent) Bytes() []byte {
 
 func (v LeaveNotifyEvent) ImplementsEvent() {}
 
+func (v LeaveNotifyEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[8] = NewLeaveNotifyEvent
 }
@@ -5107,6 +5231,10 @@ func (v FocusOutEvent) Bytes() []byte {
 
 func (v FocusOutEvent) ImplementsEvent() {}
 
+func (v FocusOutEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[10] = NewFocusOutEvent
 }
@@ -5127,6 +5255,10 @@ func (v CirculateRequestEvent) Bytes() []byte {
 
 func (v CirculateRequestEvent) ImplementsEvent() {}
 
+func (v CirculateRequestEvent) SequenceId() uint16 {
+	return v.Sequence
+}
+
 func init() {
 	newEventFuncs[27] = NewCirculateRequestEvent
 }
@@ -5798,10 +5930,25 @@ func init() {
 }
 
 // Request CreateWindow
-// size: (28 + (4 + pad((4 * popCount(int(ValueMask))))))
+// size: pad((28 + (4 + pad((4 * popCount(int(ValueMask)))))))
+type CreateWindowCookie cookie
+
 // Write request to wire for CreateWindow
-func (c *Conn) CreateWindow(Depth byte, Wid Id, Parent Id, X int16, Y int16, Width uint16, Height uint16, BorderWidth uint16, Class uint16, Visual Visualid, ValueMask uint32, ValueList []uint32) {
-	size := (28 + (4 + pad((4 * popCount(int(ValueMask))))))
+func (c *Conn) CreateWindow(Depth byte, Wid Id, Parent Id, X int16, Y int16, Width uint16, Height uint16, BorderWidth uint16, Class uint16, Visual Visualid, ValueMask uint32, ValueList []uint32) CreateWindowCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(createWindowRequest(Depth, Wid, Parent, X, Y, Width, Height, BorderWidth, Class, Visual, ValueMask, ValueList), cookie)
+	return CreateWindowCookie(cookie)
+}
+
+func (c *Conn) CreateWindowChecked(Depth byte, Wid Id, Parent Id, X int16, Y int16, Width uint16, Height uint16, BorderWidth uint16, Class uint16, Visual Visualid, ValueMask uint32, ValueList []uint32) CreateWindowCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(createWindowRequest(Depth, Wid, Parent, X, Y, Width, Height, BorderWidth, Class, Visual, ValueMask, ValueList), cookie)
+	return CreateWindowCookie(cookie)
+}
+
+// Write request to wire for CreateWindow
+func createWindowRequest(Depth byte, Wid Id, Parent Id, X int16, Y int16, Width uint16, Height uint16, BorderWidth uint16, Class uint16, Visual Visualid, ValueMask uint32, ValueList []uint32) []byte {
+	size := pad((28 + (4 + pad((4 * popCount(int(ValueMask)))))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -5849,14 +5996,29 @@ func (c *Conn) CreateWindow(Depth byte, Wid Id, Parent Id, X int16, Y int16, Wid
 	}
 	b = pad(b)
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request ChangeWindowAttributes
-// size: (8 + (4 + pad((4 * popCount(int(ValueMask))))))
+// size: pad((8 + (4 + pad((4 * popCount(int(ValueMask)))))))
+type ChangeWindowAttributesCookie cookie
+
 // Write request to wire for ChangeWindowAttributes
-func (c *Conn) ChangeWindowAttributes(Window Id, ValueMask uint32, ValueList []uint32) {
-	size := (8 + (4 + pad((4 * popCount(int(ValueMask))))))
+func (c *Conn) ChangeWindowAttributes(Window Id, ValueMask uint32, ValueList []uint32) ChangeWindowAttributesCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(changeWindowAttributesRequest(Window, ValueMask, ValueList), cookie)
+	return ChangeWindowAttributesCookie(cookie)
+}
+
+func (c *Conn) ChangeWindowAttributesChecked(Window Id, ValueMask uint32, ValueList []uint32) ChangeWindowAttributesCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(changeWindowAttributesRequest(Window, ValueMask, ValueList), cookie)
+	return ChangeWindowAttributesCookie(cookie)
+}
+
+// Write request to wire for ChangeWindowAttributes
+func changeWindowAttributesRequest(Window Id, ValueMask uint32, ValueList []uint32) []byte {
+	size := pad((8 + (4 + pad((4 * popCount(int(ValueMask)))))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -5879,33 +6041,23 @@ func (c *Conn) ChangeWindowAttributes(Window Id, ValueMask uint32, ValueList []u
 	}
 	b = pad(b)
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request GetWindowAttributes
 // size: 8
-func (c *Conn) GetWindowAttributes(Window Id) (*GetWindowAttributesReply, error) {
-	return c.GetWindowAttributesReply(c.GetWindowAttributesRequest(Window))
-}
-
-// Write request to wire for GetWindowAttributes
-func (c *Conn) GetWindowAttributesRequest(Window Id) *Cookie {
-	size := 8
-	b := 0
-	buf := make([]byte, size)
-
-	buf[b] = 3 // request opcode
-	b += 1
-
-	b += 1 // padding
+type GetWindowAttributesCookie cookie
 
-	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
-	b += 2
-
-	Put32(buf[b:], uint32(Window))
-	b += 4
+func (c *Conn) GetWindowAttributes(Window Id) GetWindowAttributesCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(getWindowAttributesRequest(Window), cookie)
+	return GetWindowAttributesCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) GetWindowAttributesUnchecked(Window Id) GetWindowAttributesCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(getWindowAttributesRequest(Window), cookie)
+	return GetWindowAttributesCookie(cookie)
 }
 
 // Request reply for GetWindowAttributes
@@ -5931,13 +6083,17 @@ type GetWindowAttributesReply struct {
 	// padding: 2 bytes
 }
 
-// Read reply GetWindowAttributes
-func (c *Conn) GetWindowAttributesReply(cook *Cookie) (*GetWindowAttributesReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request GetWindowAttributes
+func (cook GetWindowAttributesCookie) Reply() (*GetWindowAttributesReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return getWindowAttributesReply(buf), nil
+}
 
+// Read reply into structure from buffer for GetWindowAttributes
+func getWindowAttributesReply(buf []byte) *GetWindowAttributesReply {
 	v := new(GetWindowAttributesReply)
 	b := 1 // skip reply determinant
 
@@ -6006,13 +6162,48 @@ func (c *Conn) GetWindowAttributesReply(cook *Cookie) (*GetWindowAttributesReply
 
 	b += 2 // padding
 
-	return v, nil
+	return v
+}
+
+// Write request to wire for GetWindowAttributes
+func getWindowAttributesRequest(Window Id) []byte {
+	size := 8
+	b := 0
+	buf := make([]byte, size)
+
+	buf[b] = 3 // request opcode
+	b += 1
+
+	b += 1 // padding
+
+	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
+	b += 2
+
+	Put32(buf[b:], uint32(Window))
+	b += 4
+
+	return buf
 }
 
 // Request DestroyWindow
 // size: 8
+type DestroyWindowCookie cookie
+
 // Write request to wire for DestroyWindow
-func (c *Conn) DestroyWindow(Window Id) {
+func (c *Conn) DestroyWindow(Window Id) DestroyWindowCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(destroyWindowRequest(Window), cookie)
+	return DestroyWindowCookie(cookie)
+}
+
+func (c *Conn) DestroyWindowChecked(Window Id) DestroyWindowCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(destroyWindowRequest(Window), cookie)
+	return DestroyWindowCookie(cookie)
+}
+
+// Write request to wire for DestroyWindow
+func destroyWindowRequest(Window Id) []byte {
 	size := 8
 	b := 0
 	buf := make([]byte, size)
@@ -6028,13 +6219,28 @@ func (c *Conn) DestroyWindow(Window Id) {
 	Put32(buf[b:], uint32(Window))
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request DestroySubwindows
 // size: 8
+type DestroySubwindowsCookie cookie
+
 // Write request to wire for DestroySubwindows
-func (c *Conn) DestroySubwindows(Window Id) {
+func (c *Conn) DestroySubwindows(Window Id) DestroySubwindowsCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(destroySubwindowsRequest(Window), cookie)
+	return DestroySubwindowsCookie(cookie)
+}
+
+func (c *Conn) DestroySubwindowsChecked(Window Id) DestroySubwindowsCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(destroySubwindowsRequest(Window), cookie)
+	return DestroySubwindowsCookie(cookie)
+}
+
+// Write request to wire for DestroySubwindows
+func destroySubwindowsRequest(Window Id) []byte {
 	size := 8
 	b := 0
 	buf := make([]byte, size)
@@ -6050,13 +6256,28 @@ func (c *Conn) DestroySubwindows(Window Id) {
 	Put32(buf[b:], uint32(Window))
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request ChangeSaveSet
 // size: 8
+type ChangeSaveSetCookie cookie
+
 // Write request to wire for ChangeSaveSet
-func (c *Conn) ChangeSaveSet(Mode byte, Window Id) {
+func (c *Conn) ChangeSaveSet(Mode byte, Window Id) ChangeSaveSetCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(changeSaveSetRequest(Mode, Window), cookie)
+	return ChangeSaveSetCookie(cookie)
+}
+
+func (c *Conn) ChangeSaveSetChecked(Mode byte, Window Id) ChangeSaveSetCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(changeSaveSetRequest(Mode, Window), cookie)
+	return ChangeSaveSetCookie(cookie)
+}
+
+// Write request to wire for ChangeSaveSet
+func changeSaveSetRequest(Mode byte, Window Id) []byte {
 	size := 8
 	b := 0
 	buf := make([]byte, size)
@@ -6073,13 +6294,28 @@ func (c *Conn) ChangeSaveSet(Mode byte, Window Id) {
 	Put32(buf[b:], uint32(Window))
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request ReparentWindow
 // size: 16
+type ReparentWindowCookie cookie
+
+// Write request to wire for ReparentWindow
+func (c *Conn) ReparentWindow(Window Id, Parent Id, X int16, Y int16) ReparentWindowCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(reparentWindowRequest(Window, Parent, X, Y), cookie)
+	return ReparentWindowCookie(cookie)
+}
+
+func (c *Conn) ReparentWindowChecked(Window Id, Parent Id, X int16, Y int16) ReparentWindowCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(reparentWindowRequest(Window, Parent, X, Y), cookie)
+	return ReparentWindowCookie(cookie)
+}
+
 // Write request to wire for ReparentWindow
-func (c *Conn) ReparentWindow(Window Id, Parent Id, X int16, Y int16) {
+func reparentWindowRequest(Window Id, Parent Id, X int16, Y int16) []byte {
 	size := 16
 	b := 0
 	buf := make([]byte, size)
@@ -6104,13 +6340,28 @@ func (c *Conn) ReparentWindow(Window Id, Parent Id, X int16, Y int16) {
 	Put16(buf[b:], uint16(Y))
 	b += 2
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request MapWindow
 // size: 8
+type MapWindowCookie cookie
+
+// Write request to wire for MapWindow
+func (c *Conn) MapWindow(Window Id) MapWindowCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(mapWindowRequest(Window), cookie)
+	return MapWindowCookie(cookie)
+}
+
+func (c *Conn) MapWindowChecked(Window Id) MapWindowCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(mapWindowRequest(Window), cookie)
+	return MapWindowCookie(cookie)
+}
+
 // Write request to wire for MapWindow
-func (c *Conn) MapWindow(Window Id) {
+func mapWindowRequest(Window Id) []byte {
 	size := 8
 	b := 0
 	buf := make([]byte, size)
@@ -6126,13 +6377,28 @@ func (c *Conn) MapWindow(Window Id) {
 	Put32(buf[b:], uint32(Window))
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request MapSubwindows
 // size: 8
+type MapSubwindowsCookie cookie
+
+// Write request to wire for MapSubwindows
+func (c *Conn) MapSubwindows(Window Id) MapSubwindowsCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(mapSubwindowsRequest(Window), cookie)
+	return MapSubwindowsCookie(cookie)
+}
+
+func (c *Conn) MapSubwindowsChecked(Window Id) MapSubwindowsCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(mapSubwindowsRequest(Window), cookie)
+	return MapSubwindowsCookie(cookie)
+}
+
 // Write request to wire for MapSubwindows
-func (c *Conn) MapSubwindows(Window Id) {
+func mapSubwindowsRequest(Window Id) []byte {
 	size := 8
 	b := 0
 	buf := make([]byte, size)
@@ -6148,13 +6414,28 @@ func (c *Conn) MapSubwindows(Window Id) {
 	Put32(buf[b:], uint32(Window))
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request UnmapWindow
 // size: 8
+type UnmapWindowCookie cookie
+
+// Write request to wire for UnmapWindow
+func (c *Conn) UnmapWindow(Window Id) UnmapWindowCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(unmapWindowRequest(Window), cookie)
+	return UnmapWindowCookie(cookie)
+}
+
+func (c *Conn) UnmapWindowChecked(Window Id) UnmapWindowCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(unmapWindowRequest(Window), cookie)
+	return UnmapWindowCookie(cookie)
+}
+
 // Write request to wire for UnmapWindow
-func (c *Conn) UnmapWindow(Window Id) {
+func unmapWindowRequest(Window Id) []byte {
 	size := 8
 	b := 0
 	buf := make([]byte, size)
@@ -6170,13 +6451,28 @@ func (c *Conn) UnmapWindow(Window Id) {
 	Put32(buf[b:], uint32(Window))
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request UnmapSubwindows
 // size: 8
+type UnmapSubwindowsCookie cookie
+
 // Write request to wire for UnmapSubwindows
-func (c *Conn) UnmapSubwindows(Window Id) {
+func (c *Conn) UnmapSubwindows(Window Id) UnmapSubwindowsCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(unmapSubwindowsRequest(Window), cookie)
+	return UnmapSubwindowsCookie(cookie)
+}
+
+func (c *Conn) UnmapSubwindowsChecked(Window Id) UnmapSubwindowsCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(unmapSubwindowsRequest(Window), cookie)
+	return UnmapSubwindowsCookie(cookie)
+}
+
+// Write request to wire for UnmapSubwindows
+func unmapSubwindowsRequest(Window Id) []byte {
 	size := 8
 	b := 0
 	buf := make([]byte, size)
@@ -6192,14 +6488,29 @@ func (c *Conn) UnmapSubwindows(Window Id) {
 	Put32(buf[b:], uint32(Window))
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request ConfigureWindow
-// size: (10 + (2 + pad((4 * popCount(int(ValueMask))))))
+// size: pad((10 + (2 + pad((4 * popCount(int(ValueMask)))))))
+type ConfigureWindowCookie cookie
+
+// Write request to wire for ConfigureWindow
+func (c *Conn) ConfigureWindow(Window Id, ValueMask uint16, ValueList []uint32) ConfigureWindowCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(configureWindowRequest(Window, ValueMask, ValueList), cookie)
+	return ConfigureWindowCookie(cookie)
+}
+
+func (c *Conn) ConfigureWindowChecked(Window Id, ValueMask uint16, ValueList []uint32) ConfigureWindowCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(configureWindowRequest(Window, ValueMask, ValueList), cookie)
+	return ConfigureWindowCookie(cookie)
+}
+
 // Write request to wire for ConfigureWindow
-func (c *Conn) ConfigureWindow(Window Id, ValueMask uint16, ValueList []uint32) {
-	size := (10 + (2 + pad((4 * popCount(int(ValueMask))))))
+func configureWindowRequest(Window Id, ValueMask uint16, ValueList []uint32) []byte {
+	size := pad((10 + (2 + pad((4 * popCount(int(ValueMask)))))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -6225,13 +6536,28 @@ func (c *Conn) ConfigureWindow(Window Id, ValueMask uint16, ValueList []uint32)
 	}
 	b = pad(b)
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request CirculateWindow
 // size: 8
+type CirculateWindowCookie cookie
+
 // Write request to wire for CirculateWindow
-func (c *Conn) CirculateWindow(Direction byte, Window Id) {
+func (c *Conn) CirculateWindow(Direction byte, Window Id) CirculateWindowCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(circulateWindowRequest(Direction, Window), cookie)
+	return CirculateWindowCookie(cookie)
+}
+
+func (c *Conn) CirculateWindowChecked(Direction byte, Window Id) CirculateWindowCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(circulateWindowRequest(Direction, Window), cookie)
+	return CirculateWindowCookie(cookie)
+}
+
+// Write request to wire for CirculateWindow
+func circulateWindowRequest(Direction byte, Window Id) []byte {
 	size := 8
 	b := 0
 	buf := make([]byte, size)
@@ -6248,33 +6574,23 @@ func (c *Conn) CirculateWindow(Direction byte, Window Id) {
 	Put32(buf[b:], uint32(Window))
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request GetGeometry
 // size: 8
-func (c *Conn) GetGeometry(Drawable Id) (*GetGeometryReply, error) {
-	return c.GetGeometryReply(c.GetGeometryRequest(Drawable))
-}
+type GetGeometryCookie cookie
 
-// Write request to wire for GetGeometry
-func (c *Conn) GetGeometryRequest(Drawable Id) *Cookie {
-	size := 8
-	b := 0
-	buf := make([]byte, size)
-
-	buf[b] = 14 // request opcode
-	b += 1
-
-	b += 1 // padding
-
-	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
-	b += 2
-
-	Put32(buf[b:], uint32(Drawable))
-	b += 4
+func (c *Conn) GetGeometry(Drawable Id) GetGeometryCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(getGeometryRequest(Drawable), cookie)
+	return GetGeometryCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) GetGeometryUnchecked(Drawable Id) GetGeometryCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(getGeometryRequest(Drawable), cookie)
+	return GetGeometryCookie(cookie)
 }
 
 // Request reply for GetGeometry
@@ -6292,13 +6608,17 @@ type GetGeometryReply struct {
 	// padding: 2 bytes
 }
 
-// Read reply GetGeometry
-func (c *Conn) GetGeometryReply(cook *Cookie) (*GetGeometryReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request GetGeometry
+func (cook GetGeometryCookie) Reply() (*GetGeometryReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return getGeometryReply(buf), nil
+}
 
+// Read reply into structure from buffer for GetGeometry
+func getGeometryReply(buf []byte) *GetGeometryReply {
 	v := new(GetGeometryReply)
 	b := 1 // skip reply determinant
 
@@ -6331,22 +6651,16 @@ func (c *Conn) GetGeometryReply(cook *Cookie) (*GetGeometryReply, error) {
 
 	b += 2 // padding
 
-	return v, nil
-}
-
-// Request QueryTree
-// size: 8
-func (c *Conn) QueryTree(Window Id) (*QueryTreeReply, error) {
-	return c.QueryTreeReply(c.QueryTreeRequest(Window))
+	return v
 }
 
-// Write request to wire for QueryTree
-func (c *Conn) QueryTreeRequest(Window Id) *Cookie {
+// Write request to wire for GetGeometry
+func getGeometryRequest(Drawable Id) []byte {
 	size := 8
 	b := 0
 	buf := make([]byte, size)
 
-	buf[b] = 15 // request opcode
+	buf[b] = 14 // request opcode
 	b += 1
 
 	b += 1 // padding
@@ -6354,10 +6668,26 @@ func (c *Conn) QueryTreeRequest(Window Id) *Cookie {
 	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
 	b += 2
 
-	Put32(buf[b:], uint32(Window))
+	Put32(buf[b:], uint32(Drawable))
 	b += 4
 
-	return c.sendRequest(true, buf)
+	return buf
+}
+
+// Request QueryTree
+// size: 8
+type QueryTreeCookie cookie
+
+func (c *Conn) QueryTree(Window Id) QueryTreeCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(queryTreeRequest(Window), cookie)
+	return QueryTreeCookie(cookie)
+}
+
+func (c *Conn) QueryTreeUnchecked(Window Id) QueryTreeCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(queryTreeRequest(Window), cookie)
+	return QueryTreeCookie(cookie)
 }
 
 // Request reply for QueryTree
@@ -6373,13 +6703,17 @@ type QueryTreeReply struct {
 	Children []Id // size: pad((int(ChildrenLen) * 4))
 }
 
-// Read reply QueryTree
-func (c *Conn) QueryTreeReply(cook *Cookie) (*QueryTreeReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request QueryTree
+func (cook QueryTreeCookie) Reply() (*QueryTreeReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return queryTreeReply(buf), nil
+}
 
+// Read reply into structure from buffer for QueryTree
+func queryTreeReply(buf []byte) *QueryTreeReply {
 	v := new(QueryTreeReply)
 	b := 1 // skip reply determinant
 
@@ -6409,43 +6743,43 @@ func (c *Conn) QueryTreeReply(cook *Cookie) (*QueryTreeReply, error) {
 	}
 	b = pad(b)
 
-	return v, nil
-}
-
-// Request InternAtom
-// size: (8 + pad((int(NameLen) * 1)))
-func (c *Conn) InternAtom(OnlyIfExists bool, NameLen uint16, Name string) (*InternAtomReply, error) {
-	return c.InternAtomReply(c.InternAtomRequest(OnlyIfExists, NameLen, Name))
+	return v
 }
 
-// Write request to wire for InternAtom
-func (c *Conn) InternAtomRequest(OnlyIfExists bool, NameLen uint16, Name string) *Cookie {
-	size := (8 + pad((int(NameLen) * 1)))
+// Write request to wire for QueryTree
+func queryTreeRequest(Window Id) []byte {
+	size := 8
 	b := 0
 	buf := make([]byte, size)
 
-	buf[b] = 16 // request opcode
+	buf[b] = 15 // request opcode
 	b += 1
 
-	if OnlyIfExists {
-		buf[b] = 1
-	} else {
-		buf[b] = 0
-	}
-	b += 1
+	b += 1 // padding
 
 	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
 	b += 2
 
-	Put16(buf[b:], NameLen)
-	b += 2
+	Put32(buf[b:], uint32(Window))
+	b += 4
 
-	b += 2 // padding
+	return buf
+}
 
-	copy(buf[b:], Name[:NameLen])
-	b += pad(int(NameLen))
+// Request InternAtom
+// size: pad((8 + pad((int(NameLen) * 1))))
+type InternAtomCookie cookie
+
+func (c *Conn) InternAtom(OnlyIfExists bool, NameLen uint16, Name string) InternAtomCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(internAtomRequest(OnlyIfExists, NameLen, Name), cookie)
+	return InternAtomCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) InternAtomUnchecked(OnlyIfExists bool, NameLen uint16, Name string) InternAtomCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(internAtomRequest(OnlyIfExists, NameLen, Name), cookie)
+	return InternAtomCookie(cookie)
 }
 
 // Request reply for InternAtom
@@ -6457,13 +6791,17 @@ type InternAtomReply struct {
 	Atom Id
 }
 
-// Read reply InternAtom
-func (c *Conn) InternAtomReply(cook *Cookie) (*InternAtomReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request InternAtom
+func (cook InternAtomCookie) Reply() (*InternAtomReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return internAtomReply(buf), nil
+}
 
+// Read reply into structure from buffer for InternAtom
+func internAtomReply(buf []byte) *InternAtomReply {
 	v := new(InternAtomReply)
 	b := 1 // skip reply determinant
 
@@ -6478,33 +6816,53 @@ func (c *Conn) InternAtomReply(cook *Cookie) (*InternAtomReply, error) {
 	v.Atom = Id(Get32(buf[b:]))
 	b += 4
 
-	return v, nil
-}
-
-// Request GetAtomName
-// size: 8
-func (c *Conn) GetAtomName(Atom Id) (*GetAtomNameReply, error) {
-	return c.GetAtomNameReply(c.GetAtomNameRequest(Atom))
+	return v
 }
 
-// Write request to wire for GetAtomName
-func (c *Conn) GetAtomNameRequest(Atom Id) *Cookie {
-	size := 8
+// Write request to wire for InternAtom
+func internAtomRequest(OnlyIfExists bool, NameLen uint16, Name string) []byte {
+	size := pad((8 + pad((int(NameLen) * 1))))
 	b := 0
 	buf := make([]byte, size)
 
-	buf[b] = 17 // request opcode
+	buf[b] = 16 // request opcode
 	b += 1
 
-	b += 1 // padding
+	if OnlyIfExists {
+		buf[b] = 1
+	} else {
+		buf[b] = 0
+	}
+	b += 1
 
 	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
 	b += 2
 
-	Put32(buf[b:], uint32(Atom))
-	b += 4
+	Put16(buf[b:], NameLen)
+	b += 2
 
-	return c.sendRequest(true, buf)
+	b += 2 // padding
+
+	copy(buf[b:], Name[:NameLen])
+	b += pad(int(NameLen))
+
+	return buf
+}
+
+// Request GetAtomName
+// size: 8
+type GetAtomNameCookie cookie
+
+func (c *Conn) GetAtomName(Atom Id) GetAtomNameCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(getAtomNameRequest(Atom), cookie)
+	return GetAtomNameCookie(cookie)
+}
+
+func (c *Conn) GetAtomNameUnchecked(Atom Id) GetAtomNameCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(getAtomNameRequest(Atom), cookie)
+	return GetAtomNameCookie(cookie)
 }
 
 // Request reply for GetAtomName
@@ -6518,13 +6876,17 @@ type GetAtomNameReply struct {
 	Name string // size: pad((int(NameLen) * 1))
 }
 
-// Read reply GetAtomName
-func (c *Conn) GetAtomNameReply(cook *Cookie) (*GetAtomNameReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request GetAtomName
+func (cook GetAtomNameCookie) Reply() (*GetAtomNameReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return getAtomNameReply(buf), nil
+}
 
+// Read reply into structure from buffer for GetAtomName
+func getAtomNameReply(buf []byte) *GetAtomNameReply {
 	v := new(GetAtomNameReply)
 	b := 1 // skip reply determinant
 
@@ -6548,14 +6910,49 @@ func (c *Conn) GetAtomNameReply(cook *Cookie) (*GetAtomNameReply, error) {
 		b += pad(int(v.NameLen))
 	}
 
-	return v, nil
+	return v
+}
+
+// Write request to wire for GetAtomName
+func getAtomNameRequest(Atom Id) []byte {
+	size := 8
+	b := 0
+	buf := make([]byte, size)
+
+	buf[b] = 17 // request opcode
+	b += 1
+
+	b += 1 // padding
+
+	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
+	b += 2
+
+	Put32(buf[b:], uint32(Atom))
+	b += 4
+
+	return buf
 }
 
 // Request ChangeProperty
-// size: (24 + pad((((int(DataLen) * int(Format)) / 8) * 1)))
+// size: pad((24 + pad((((int(DataLen) * int(Format)) / 8) * 1))))
+type ChangePropertyCookie cookie
+
+// Write request to wire for ChangeProperty
+func (c *Conn) ChangeProperty(Mode byte, Window Id, Property Id, Type Id, Format byte, DataLen uint32, Data []byte) ChangePropertyCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(changePropertyRequest(Mode, Window, Property, Type, Format, DataLen, Data), cookie)
+	return ChangePropertyCookie(cookie)
+}
+
+func (c *Conn) ChangePropertyChecked(Mode byte, Window Id, Property Id, Type Id, Format byte, DataLen uint32, Data []byte) ChangePropertyCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(changePropertyRequest(Mode, Window, Property, Type, Format, DataLen, Data), cookie)
+	return ChangePropertyCookie(cookie)
+}
+
 // Write request to wire for ChangeProperty
-func (c *Conn) ChangeProperty(Mode byte, Window Id, Property Id, Type Id, Format byte, DataLen uint32, Data []byte) {
-	size := (24 + pad((((int(DataLen) * int(Format)) / 8) * 1)))
+func changePropertyRequest(Mode byte, Window Id, Property Id, Type Id, Format byte, DataLen uint32, Data []byte) []byte {
+	size := pad((24 + pad((((int(DataLen) * int(Format)) / 8) * 1))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -6588,13 +6985,28 @@ func (c *Conn) ChangeProperty(Mode byte, Window Id, Property Id, Type Id, Format
 	copy(buf[b:], Data[:((int(DataLen)*int(Format))/8)])
 	b += pad(int(((int(DataLen) * int(Format)) / 8)))
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request DeleteProperty
 // size: 12
+type DeletePropertyCookie cookie
+
 // Write request to wire for DeleteProperty
-func (c *Conn) DeleteProperty(Window Id, Property Id) {
+func (c *Conn) DeleteProperty(Window Id, Property Id) DeletePropertyCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(deletePropertyRequest(Window, Property), cookie)
+	return DeletePropertyCookie(cookie)
+}
+
+func (c *Conn) DeletePropertyChecked(Window Id, Property Id) DeletePropertyCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(deletePropertyRequest(Window, Property), cookie)
+	return DeletePropertyCookie(cookie)
+}
+
+// Write request to wire for DeleteProperty
+func deletePropertyRequest(Window Id, Property Id) []byte {
 	size := 12
 	b := 0
 	buf := make([]byte, size)
@@ -6613,50 +7025,23 @@ func (c *Conn) DeleteProperty(Window Id, Property Id) {
 	Put32(buf[b:], uint32(Property))
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request GetProperty
 // size: 24
-func (c *Conn) GetProperty(Delete bool, Window Id, Property Id, Type Id, LongOffset uint32, LongLength uint32) (*GetPropertyReply, error) {
-	return c.GetPropertyReply(c.GetPropertyRequest(Delete, Window, Property, Type, LongOffset, LongLength))
-}
-
-// Write request to wire for GetProperty
-func (c *Conn) GetPropertyRequest(Delete bool, Window Id, Property Id, Type Id, LongOffset uint32, LongLength uint32) *Cookie {
-	size := 24
-	b := 0
-	buf := make([]byte, size)
-
-	buf[b] = 20 // request opcode
-	b += 1
-
-	if Delete {
-		buf[b] = 1
-	} else {
-		buf[b] = 0
-	}
-	b += 1
+type GetPropertyCookie cookie
 
-	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
-	b += 2
-
-	Put32(buf[b:], uint32(Window))
-	b += 4
-
-	Put32(buf[b:], uint32(Property))
-	b += 4
-
-	Put32(buf[b:], uint32(Type))
-	b += 4
-
-	Put32(buf[b:], LongOffset)
-	b += 4
-
-	Put32(buf[b:], LongLength)
-	b += 4
+func (c *Conn) GetProperty(Delete bool, Window Id, Property Id, Type Id, LongOffset uint32, LongLength uint32) GetPropertyCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(getPropertyRequest(Delete, Window, Property, Type, LongOffset, LongLength), cookie)
+	return GetPropertyCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) GetPropertyUnchecked(Delete bool, Window Id, Property Id, Type Id, LongOffset uint32, LongLength uint32) GetPropertyCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(getPropertyRequest(Delete, Window, Property, Type, LongOffset, LongLength), cookie)
+	return GetPropertyCookie(cookie)
 }
 
 // Request reply for GetProperty
@@ -6672,13 +7057,17 @@ type GetPropertyReply struct {
 	Value []byte // size: pad(((int(ValueLen) * (int(Format) / 8)) * 1))
 }
 
-// Read reply GetProperty
-func (c *Conn) GetPropertyReply(cook *Cookie) (*GetPropertyReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request GetProperty
+func (cook GetPropertyCookie) Reply() (*GetPropertyReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return getPropertyReply(buf), nil
+}
 
+// Read reply into structure from buffer for GetProperty
+func getPropertyReply(buf []byte) *GetPropertyReply {
 	v := new(GetPropertyReply)
 	b := 1 // skip reply determinant
 
@@ -6706,25 +7095,24 @@ func (c *Conn) GetPropertyReply(cook *Cookie) (*GetPropertyReply, error) {
 	copy(v.Value[:(int(v.ValueLen)*(int(v.Format)/8))], buf[b:])
 	b += pad(int((int(v.ValueLen) * (int(v.Format) / 8))))
 
-	return v, nil
-}
-
-// Request ListProperties
-// size: 8
-func (c *Conn) ListProperties(Window Id) (*ListPropertiesReply, error) {
-	return c.ListPropertiesReply(c.ListPropertiesRequest(Window))
+	return v
 }
 
-// Write request to wire for ListProperties
-func (c *Conn) ListPropertiesRequest(Window Id) *Cookie {
-	size := 8
+// Write request to wire for GetProperty
+func getPropertyRequest(Delete bool, Window Id, Property Id, Type Id, LongOffset uint32, LongLength uint32) []byte {
+	size := 24
 	b := 0
 	buf := make([]byte, size)
 
-	buf[b] = 21 // request opcode
+	buf[b] = 20 // request opcode
 	b += 1
 
-	b += 1 // padding
+	if Delete {
+		buf[b] = 1
+	} else {
+		buf[b] = 0
+	}
+	b += 1
 
 	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
 	b += 2
@@ -6732,7 +7120,35 @@ func (c *Conn) ListPropertiesRequest(Window Id) *Cookie {
 	Put32(buf[b:], uint32(Window))
 	b += 4
 
-	return c.sendRequest(true, buf)
+	Put32(buf[b:], uint32(Property))
+	b += 4
+
+	Put32(buf[b:], uint32(Type))
+	b += 4
+
+	Put32(buf[b:], LongOffset)
+	b += 4
+
+	Put32(buf[b:], LongLength)
+	b += 4
+
+	return buf
+}
+
+// Request ListProperties
+// size: 8
+type ListPropertiesCookie cookie
+
+func (c *Conn) ListProperties(Window Id) ListPropertiesCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(listPropertiesRequest(Window), cookie)
+	return ListPropertiesCookie(cookie)
+}
+
+func (c *Conn) ListPropertiesUnchecked(Window Id) ListPropertiesCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(listPropertiesRequest(Window), cookie)
+	return ListPropertiesCookie(cookie)
 }
 
 // Request reply for ListProperties
@@ -6746,13 +7162,17 @@ type ListPropertiesReply struct {
 	Atoms []Id // size: pad((int(AtomsLen) * 4))
 }
 
-// Read reply ListProperties
-func (c *Conn) ListPropertiesReply(cook *Cookie) (*ListPropertiesReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request ListProperties
+func (cook ListPropertiesCookie) Reply() (*ListPropertiesReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return listPropertiesReply(buf), nil
+}
 
+// Read reply into structure from buffer for ListProperties
+func listPropertiesReply(buf []byte) *ListPropertiesReply {
 	v := new(ListPropertiesReply)
 	b := 1 // skip reply determinant
 
@@ -6776,18 +7196,16 @@ func (c *Conn) ListPropertiesReply(cook *Cookie) (*ListPropertiesReply, error) {
 	}
 	b = pad(b)
 
-	return v, nil
+	return v
 }
 
-// Request SetSelectionOwner
-// size: 16
-// Write request to wire for SetSelectionOwner
-func (c *Conn) SetSelectionOwner(Owner Id, Selection Id, Time Timestamp) {
-	size := 16
+// Write request to wire for ListProperties
+func listPropertiesRequest(Window Id) []byte {
+	size := 8
 	b := 0
 	buf := make([]byte, size)
 
-	buf[b] = 22 // request opcode
+	buf[b] = 21 // request opcode
 	b += 1
 
 	b += 1 // padding
@@ -6795,31 +7213,36 @@ func (c *Conn) SetSelectionOwner(Owner Id, Selection Id, Time Timestamp) {
 	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
 	b += 2
 
-	Put32(buf[b:], uint32(Owner))
+	Put32(buf[b:], uint32(Window))
 	b += 4
 
-	Put32(buf[b:], uint32(Selection))
-	b += 4
+	return buf
+}
 
-	Put32(buf[b:], uint32(Time))
-	b += 4
+// Request SetSelectionOwner
+// size: 16
+type SetSelectionOwnerCookie cookie
 
-	c.sendRequest(false, buf)
+// Write request to wire for SetSelectionOwner
+func (c *Conn) SetSelectionOwner(Owner Id, Selection Id, Time Timestamp) SetSelectionOwnerCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(setSelectionOwnerRequest(Owner, Selection, Time), cookie)
+	return SetSelectionOwnerCookie(cookie)
 }
 
-// Request GetSelectionOwner
-// size: 8
-func (c *Conn) GetSelectionOwner(Selection Id) (*GetSelectionOwnerReply, error) {
-	return c.GetSelectionOwnerReply(c.GetSelectionOwnerRequest(Selection))
+func (c *Conn) SetSelectionOwnerChecked(Owner Id, Selection Id, Time Timestamp) SetSelectionOwnerCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(setSelectionOwnerRequest(Owner, Selection, Time), cookie)
+	return SetSelectionOwnerCookie(cookie)
 }
 
-// Write request to wire for GetSelectionOwner
-func (c *Conn) GetSelectionOwnerRequest(Selection Id) *Cookie {
-	size := 8
+// Write request to wire for SetSelectionOwner
+func setSelectionOwnerRequest(Owner Id, Selection Id, Time Timestamp) []byte {
+	size := 16
 	b := 0
 	buf := make([]byte, size)
 
-	buf[b] = 23 // request opcode
+	buf[b] = 22 // request opcode
 	b += 1
 
 	b += 1 // padding
@@ -6827,10 +7250,32 @@ func (c *Conn) GetSelectionOwnerRequest(Selection Id) *Cookie {
 	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
 	b += 2
 
+	Put32(buf[b:], uint32(Owner))
+	b += 4
+
 	Put32(buf[b:], uint32(Selection))
 	b += 4
 
-	return c.sendRequest(true, buf)
+	Put32(buf[b:], uint32(Time))
+	b += 4
+
+	return buf
+}
+
+// Request GetSelectionOwner
+// size: 8
+type GetSelectionOwnerCookie cookie
+
+func (c *Conn) GetSelectionOwner(Selection Id) GetSelectionOwnerCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(getSelectionOwnerRequest(Selection), cookie)
+	return GetSelectionOwnerCookie(cookie)
+}
+
+func (c *Conn) GetSelectionOwnerUnchecked(Selection Id) GetSelectionOwnerCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(getSelectionOwnerRequest(Selection), cookie)
+	return GetSelectionOwnerCookie(cookie)
 }
 
 // Request reply for GetSelectionOwner
@@ -6842,13 +7287,17 @@ type GetSelectionOwnerReply struct {
 	Owner Id
 }
 
-// Read reply GetSelectionOwner
-func (c *Conn) GetSelectionOwnerReply(cook *Cookie) (*GetSelectionOwnerReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request GetSelectionOwner
+func (cook GetSelectionOwnerCookie) Reply() (*GetSelectionOwnerReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return getSelectionOwnerReply(buf), nil
+}
 
+// Read reply into structure from buffer for GetSelectionOwner
+func getSelectionOwnerReply(buf []byte) *GetSelectionOwnerReply {
 	v := new(GetSelectionOwnerReply)
 	b := 1 // skip reply determinant
 
@@ -6863,13 +7312,48 @@ func (c *Conn) GetSelectionOwnerReply(cook *Cookie) (*GetSelectionOwnerReply, er
 	v.Owner = Id(Get32(buf[b:]))
 	b += 4
 
-	return v, nil
+	return v
+}
+
+// Write request to wire for GetSelectionOwner
+func getSelectionOwnerRequest(Selection Id) []byte {
+	size := 8
+	b := 0
+	buf := make([]byte, size)
+
+	buf[b] = 23 // request opcode
+	b += 1
+
+	b += 1 // padding
+
+	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
+	b += 2
+
+	Put32(buf[b:], uint32(Selection))
+	b += 4
+
+	return buf
 }
 
 // Request ConvertSelection
 // size: 24
+type ConvertSelectionCookie cookie
+
+// Write request to wire for ConvertSelection
+func (c *Conn) ConvertSelection(Requestor Id, Selection Id, Target Id, Property Id, Time Timestamp) ConvertSelectionCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(convertSelectionRequest(Requestor, Selection, Target, Property, Time), cookie)
+	return ConvertSelectionCookie(cookie)
+}
+
+func (c *Conn) ConvertSelectionChecked(Requestor Id, Selection Id, Target Id, Property Id, Time Timestamp) ConvertSelectionCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(convertSelectionRequest(Requestor, Selection, Target, Property, Time), cookie)
+	return ConvertSelectionCookie(cookie)
+}
+
 // Write request to wire for ConvertSelection
-func (c *Conn) ConvertSelection(Requestor Id, Selection Id, Target Id, Property Id, Time Timestamp) {
+func convertSelectionRequest(Requestor Id, Selection Id, Target Id, Property Id, Time Timestamp) []byte {
 	size := 24
 	b := 0
 	buf := make([]byte, size)
@@ -6897,14 +7381,29 @@ func (c *Conn) ConvertSelection(Requestor Id, Selection Id, Target Id, Property
 	Put32(buf[b:], uint32(Time))
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request SendEvent
-// size: (12 + pad(32))
+// size: pad((12 + pad(32)))
+type SendEventCookie cookie
+
 // Write request to wire for SendEvent
-func (c *Conn) SendEvent(Propagate bool, Destination Id, EventMask uint32, Event string) {
-	size := (12 + pad(32))
+func (c *Conn) SendEvent(Propagate bool, Destination Id, EventMask uint32, Event string) SendEventCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(sendEventRequest(Propagate, Destination, EventMask, Event), cookie)
+	return SendEventCookie(cookie)
+}
+
+func (c *Conn) SendEventChecked(Propagate bool, Destination Id, EventMask uint32, Event string) SendEventCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(sendEventRequest(Propagate, Destination, EventMask, Event), cookie)
+	return SendEventCookie(cookie)
+}
+
+// Write request to wire for SendEvent
+func sendEventRequest(Propagate bool, Destination Id, EventMask uint32, Event string) []byte {
+	size := pad((12 + pad(32)))
 	b := 0
 	buf := make([]byte, size)
 
@@ -6930,17 +7429,55 @@ func (c *Conn) SendEvent(Propagate bool, Destination Id, EventMask uint32, Event
 	copy(buf[b:], Event[:32])
 	b += pad(int(32))
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request GrabPointer
 // size: 24
-func (c *Conn) GrabPointer(OwnerEvents bool, GrabWindow Id, EventMask uint16, PointerMode byte, KeyboardMode byte, ConfineTo Id, Cursor Id, Time Timestamp) (*GrabPointerReply, error) {
-	return c.GrabPointerReply(c.GrabPointerRequest(OwnerEvents, GrabWindow, EventMask, PointerMode, KeyboardMode, ConfineTo, Cursor, Time))
+type GrabPointerCookie cookie
+
+func (c *Conn) GrabPointer(OwnerEvents bool, GrabWindow Id, EventMask uint16, PointerMode byte, KeyboardMode byte, ConfineTo Id, Cursor Id, Time Timestamp) GrabPointerCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(grabPointerRequest(OwnerEvents, GrabWindow, EventMask, PointerMode, KeyboardMode, ConfineTo, Cursor, Time), cookie)
+	return GrabPointerCookie(cookie)
+}
+
+func (c *Conn) GrabPointerUnchecked(OwnerEvents bool, GrabWindow Id, EventMask uint16, PointerMode byte, KeyboardMode byte, ConfineTo Id, Cursor Id, Time Timestamp) GrabPointerCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(grabPointerRequest(OwnerEvents, GrabWindow, EventMask, PointerMode, KeyboardMode, ConfineTo, Cursor, Time), cookie)
+	return GrabPointerCookie(cookie)
+}
+
+// Request reply for GrabPointer
+// size: 8
+type GrabPointerReply struct {
+	Sequence uint16
+	Length   uint32
+	Status   byte
+}
+
+// Waits and reads reply data from request GrabPointer
+func (cook GrabPointerCookie) Reply() (*GrabPointerReply, error) {
+	buf, err := cookie(cook).reply()
+	if err != nil {
+		return nil, err
+	}
+	return grabPointerReply(buf), nil
+}
+
+// Read reply into structure from buffer for GrabPointer
+func grabPointerReply(buf []byte) *GrabPointerReply {
+	v := new(GrabPointerReply)
+	b := 1 // skip reply determinant
+
+	v.Status = buf[b]
+	b += 1
+
+	return v
 }
 
 // Write request to wire for GrabPointer
-func (c *Conn) GrabPointerRequest(OwnerEvents bool, GrabWindow Id, EventMask uint16, PointerMode byte, KeyboardMode byte, ConfineTo Id, Cursor Id, Time Timestamp) *Cookie {
+func grabPointerRequest(OwnerEvents bool, GrabWindow Id, EventMask uint16, PointerMode byte, KeyboardMode byte, ConfineTo Id, Cursor Id, Time Timestamp) []byte {
 	size := 24
 	b := 0
 	buf := make([]byte, size)
@@ -6979,37 +7516,28 @@ func (c *Conn) GrabPointerRequest(OwnerEvents bool, GrabWindow Id, EventMask uin
 	Put32(buf[b:], uint32(Time))
 	b += 4
 
-	return c.sendRequest(true, buf)
+	return buf
 }
 
-// Request reply for GrabPointer
+// Request UngrabPointer
 // size: 8
-type GrabPointerReply struct {
-	Sequence uint16
-	Length   uint32
-	Status   byte
-}
-
-// Read reply GrabPointer
-func (c *Conn) GrabPointerReply(cook *Cookie) (*GrabPointerReply, error) {
-	buf, err := c.waitForReply(cook)
-	if err != nil {
-		return nil, err
-	}
-
-	v := new(GrabPointerReply)
-	b := 1 // skip reply determinant
+type UngrabPointerCookie cookie
 
-	v.Status = buf[b]
-	b += 1
+// Write request to wire for UngrabPointer
+func (c *Conn) UngrabPointer(Time Timestamp) UngrabPointerCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(ungrabPointerRequest(Time), cookie)
+	return UngrabPointerCookie(cookie)
+}
 
-	return v, nil
+func (c *Conn) UngrabPointerChecked(Time Timestamp) UngrabPointerCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(ungrabPointerRequest(Time), cookie)
+	return UngrabPointerCookie(cookie)
 }
 
-// Request UngrabPointer
-// size: 8
 // Write request to wire for UngrabPointer
-func (c *Conn) UngrabPointer(Time Timestamp) {
+func ungrabPointerRequest(Time Timestamp) []byte {
 	size := 8
 	b := 0
 	buf := make([]byte, size)
@@ -7025,13 +7553,28 @@ func (c *Conn) UngrabPointer(Time Timestamp) {
 	Put32(buf[b:], uint32(Time))
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request GrabButton
 // size: 24
+type GrabButtonCookie cookie
+
+// Write request to wire for GrabButton
+func (c *Conn) GrabButton(OwnerEvents bool, GrabWindow Id, EventMask uint16, PointerMode byte, KeyboardMode byte, ConfineTo Id, Cursor Id, Button byte, Modifiers uint16) GrabButtonCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(grabButtonRequest(OwnerEvents, GrabWindow, EventMask, PointerMode, KeyboardMode, ConfineTo, Cursor, Button, Modifiers), cookie)
+	return GrabButtonCookie(cookie)
+}
+
+func (c *Conn) GrabButtonChecked(OwnerEvents bool, GrabWindow Id, EventMask uint16, PointerMode byte, KeyboardMode byte, ConfineTo Id, Cursor Id, Button byte, Modifiers uint16) GrabButtonCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(grabButtonRequest(OwnerEvents, GrabWindow, EventMask, PointerMode, KeyboardMode, ConfineTo, Cursor, Button, Modifiers), cookie)
+	return GrabButtonCookie(cookie)
+}
+
 // Write request to wire for GrabButton
-func (c *Conn) GrabButton(OwnerEvents bool, GrabWindow Id, EventMask uint16, PointerMode byte, KeyboardMode byte, ConfineTo Id, Cursor Id, Button byte, Modifiers uint16) {
+func grabButtonRequest(OwnerEvents bool, GrabWindow Id, EventMask uint16, PointerMode byte, KeyboardMode byte, ConfineTo Id, Cursor Id, Button byte, Modifiers uint16) []byte {
 	size := 24
 	b := 0
 	buf := make([]byte, size)
@@ -7075,13 +7618,28 @@ func (c *Conn) GrabButton(OwnerEvents bool, GrabWindow Id, EventMask uint16, Poi
 	Put16(buf[b:], Modifiers)
 	b += 2
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request UngrabButton
 // size: 12
+type UngrabButtonCookie cookie
+
 // Write request to wire for UngrabButton
-func (c *Conn) UngrabButton(Button byte, GrabWindow Id, Modifiers uint16) {
+func (c *Conn) UngrabButton(Button byte, GrabWindow Id, Modifiers uint16) UngrabButtonCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(ungrabButtonRequest(Button, GrabWindow, Modifiers), cookie)
+	return UngrabButtonCookie(cookie)
+}
+
+func (c *Conn) UngrabButtonChecked(Button byte, GrabWindow Id, Modifiers uint16) UngrabButtonCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(ungrabButtonRequest(Button, GrabWindow, Modifiers), cookie)
+	return UngrabButtonCookie(cookie)
+}
+
+// Write request to wire for UngrabButton
+func ungrabButtonRequest(Button byte, GrabWindow Id, Modifiers uint16) []byte {
 	size := 12
 	b := 0
 	buf := make([]byte, size)
@@ -7103,13 +7661,28 @@ func (c *Conn) UngrabButton(Button byte, GrabWindow Id, Modifiers uint16) {
 
 	b += 2 // padding
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request ChangeActivePointerGrab
 // size: 16
+type ChangeActivePointerGrabCookie cookie
+
 // Write request to wire for ChangeActivePointerGrab
-func (c *Conn) ChangeActivePointerGrab(Cursor Id, Time Timestamp, EventMask uint16) {
+func (c *Conn) ChangeActivePointerGrab(Cursor Id, Time Timestamp, EventMask uint16) ChangeActivePointerGrabCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(changeActivePointerGrabRequest(Cursor, Time, EventMask), cookie)
+	return ChangeActivePointerGrabCookie(cookie)
+}
+
+func (c *Conn) ChangeActivePointerGrabChecked(Cursor Id, Time Timestamp, EventMask uint16) ChangeActivePointerGrabCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(changeActivePointerGrabRequest(Cursor, Time, EventMask), cookie)
+	return ChangeActivePointerGrabCookie(cookie)
+}
+
+// Write request to wire for ChangeActivePointerGrab
+func changeActivePointerGrabRequest(Cursor Id, Time Timestamp, EventMask uint16) []byte {
 	size := 16
 	b := 0
 	buf := make([]byte, size)
@@ -7133,17 +7706,55 @@ func (c *Conn) ChangeActivePointerGrab(Cursor Id, Time Timestamp, EventMask uint
 
 	b += 2 // padding
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request GrabKeyboard
 // size: 16
-func (c *Conn) GrabKeyboard(OwnerEvents bool, GrabWindow Id, Time Timestamp, PointerMode byte, KeyboardMode byte) (*GrabKeyboardReply, error) {
-	return c.GrabKeyboardReply(c.GrabKeyboardRequest(OwnerEvents, GrabWindow, Time, PointerMode, KeyboardMode))
+type GrabKeyboardCookie cookie
+
+func (c *Conn) GrabKeyboard(OwnerEvents bool, GrabWindow Id, Time Timestamp, PointerMode byte, KeyboardMode byte) GrabKeyboardCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(grabKeyboardRequest(OwnerEvents, GrabWindow, Time, PointerMode, KeyboardMode), cookie)
+	return GrabKeyboardCookie(cookie)
+}
+
+func (c *Conn) GrabKeyboardUnchecked(OwnerEvents bool, GrabWindow Id, Time Timestamp, PointerMode byte, KeyboardMode byte) GrabKeyboardCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(grabKeyboardRequest(OwnerEvents, GrabWindow, Time, PointerMode, KeyboardMode), cookie)
+	return GrabKeyboardCookie(cookie)
+}
+
+// Request reply for GrabKeyboard
+// size: 8
+type GrabKeyboardReply struct {
+	Sequence uint16
+	Length   uint32
+	Status   byte
+}
+
+// Waits and reads reply data from request GrabKeyboard
+func (cook GrabKeyboardCookie) Reply() (*GrabKeyboardReply, error) {
+	buf, err := cookie(cook).reply()
+	if err != nil {
+		return nil, err
+	}
+	return grabKeyboardReply(buf), nil
+}
+
+// Read reply into structure from buffer for GrabKeyboard
+func grabKeyboardReply(buf []byte) *GrabKeyboardReply {
+	v := new(GrabKeyboardReply)
+	b := 1 // skip reply determinant
+
+	v.Status = buf[b]
+	b += 1
+
+	return v
 }
 
 // Write request to wire for GrabKeyboard
-func (c *Conn) GrabKeyboardRequest(OwnerEvents bool, GrabWindow Id, Time Timestamp, PointerMode byte, KeyboardMode byte) *Cookie {
+func grabKeyboardRequest(OwnerEvents bool, GrabWindow Id, Time Timestamp, PointerMode byte, KeyboardMode byte) []byte {
 	size := 16
 	b := 0
 	buf := make([]byte, size)
@@ -7175,37 +7786,28 @@ func (c *Conn) GrabKeyboardRequest(OwnerEvents bool, GrabWindow Id, Time Timesta
 
 	b += 2 // padding
 
-	return c.sendRequest(true, buf)
+	return buf
 }
 
-// Request reply for GrabKeyboard
+// Request UngrabKeyboard
 // size: 8
-type GrabKeyboardReply struct {
-	Sequence uint16
-	Length   uint32
-	Status   byte
-}
-
-// Read reply GrabKeyboard
-func (c *Conn) GrabKeyboardReply(cook *Cookie) (*GrabKeyboardReply, error) {
-	buf, err := c.waitForReply(cook)
-	if err != nil {
-		return nil, err
-	}
-
-	v := new(GrabKeyboardReply)
-	b := 1 // skip reply determinant
+type UngrabKeyboardCookie cookie
 
-	v.Status = buf[b]
-	b += 1
+// Write request to wire for UngrabKeyboard
+func (c *Conn) UngrabKeyboard(Time Timestamp) UngrabKeyboardCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(ungrabKeyboardRequest(Time), cookie)
+	return UngrabKeyboardCookie(cookie)
+}
 
-	return v, nil
+func (c *Conn) UngrabKeyboardChecked(Time Timestamp) UngrabKeyboardCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(ungrabKeyboardRequest(Time), cookie)
+	return UngrabKeyboardCookie(cookie)
 }
 
-// Request UngrabKeyboard
-// size: 8
 // Write request to wire for UngrabKeyboard
-func (c *Conn) UngrabKeyboard(Time Timestamp) {
+func ungrabKeyboardRequest(Time Timestamp) []byte {
 	size := 8
 	b := 0
 	buf := make([]byte, size)
@@ -7221,13 +7823,28 @@ func (c *Conn) UngrabKeyboard(Time Timestamp) {
 	Put32(buf[b:], uint32(Time))
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request GrabKey
 // size: 16
+type GrabKeyCookie cookie
+
 // Write request to wire for GrabKey
-func (c *Conn) GrabKey(OwnerEvents bool, GrabWindow Id, Modifiers uint16, Key Keycode, PointerMode byte, KeyboardMode byte) {
+func (c *Conn) GrabKey(OwnerEvents bool, GrabWindow Id, Modifiers uint16, Key Keycode, PointerMode byte, KeyboardMode byte) GrabKeyCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(grabKeyRequest(OwnerEvents, GrabWindow, Modifiers, Key, PointerMode, KeyboardMode), cookie)
+	return GrabKeyCookie(cookie)
+}
+
+func (c *Conn) GrabKeyChecked(OwnerEvents bool, GrabWindow Id, Modifiers uint16, Key Keycode, PointerMode byte, KeyboardMode byte) GrabKeyCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(grabKeyRequest(OwnerEvents, GrabWindow, Modifiers, Key, PointerMode, KeyboardMode), cookie)
+	return GrabKeyCookie(cookie)
+}
+
+// Write request to wire for GrabKey
+func grabKeyRequest(OwnerEvents bool, GrabWindow Id, Modifiers uint16, Key Keycode, PointerMode byte, KeyboardMode byte) []byte {
 	size := 16
 	b := 0
 	buf := make([]byte, size)
@@ -7262,13 +7879,28 @@ func (c *Conn) GrabKey(OwnerEvents bool, GrabWindow Id, Modifiers uint16, Key Ke
 
 	b += 3 // padding
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request UngrabKey
 // size: 12
+type UngrabKeyCookie cookie
+
 // Write request to wire for UngrabKey
-func (c *Conn) UngrabKey(Key Keycode, GrabWindow Id, Modifiers uint16) {
+func (c *Conn) UngrabKey(Key Keycode, GrabWindow Id, Modifiers uint16) UngrabKeyCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(ungrabKeyRequest(Key, GrabWindow, Modifiers), cookie)
+	return UngrabKeyCookie(cookie)
+}
+
+func (c *Conn) UngrabKeyChecked(Key Keycode, GrabWindow Id, Modifiers uint16) UngrabKeyCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(ungrabKeyRequest(Key, GrabWindow, Modifiers), cookie)
+	return UngrabKeyCookie(cookie)
+}
+
+// Write request to wire for UngrabKey
+func ungrabKeyRequest(Key Keycode, GrabWindow Id, Modifiers uint16) []byte {
 	size := 12
 	b := 0
 	buf := make([]byte, size)
@@ -7290,13 +7922,28 @@ func (c *Conn) UngrabKey(Key Keycode, GrabWindow Id, Modifiers uint16) {
 
 	b += 2 // padding
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request AllowEvents
 // size: 8
+type AllowEventsCookie cookie
+
 // Write request to wire for AllowEvents
-func (c *Conn) AllowEvents(Mode byte, Time Timestamp) {
+func (c *Conn) AllowEvents(Mode byte, Time Timestamp) AllowEventsCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(allowEventsRequest(Mode, Time), cookie)
+	return AllowEventsCookie(cookie)
+}
+
+func (c *Conn) AllowEventsChecked(Mode byte, Time Timestamp) AllowEventsCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(allowEventsRequest(Mode, Time), cookie)
+	return AllowEventsCookie(cookie)
+}
+
+// Write request to wire for AllowEvents
+func allowEventsRequest(Mode byte, Time Timestamp) []byte {
 	size := 8
 	b := 0
 	buf := make([]byte, size)
@@ -7313,61 +7960,81 @@ func (c *Conn) AllowEvents(Mode byte, Time Timestamp) {
 	Put32(buf[b:], uint32(Time))
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request GrabServer
-// size: 3
+// size: 4
+type GrabServerCookie cookie
+
 // Write request to wire for GrabServer
-func (c *Conn) GrabServer() {
-	size := 3
+func (c *Conn) GrabServer() GrabServerCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(grabServerRequest(), cookie)
+	return GrabServerCookie(cookie)
+}
+
+func (c *Conn) GrabServerChecked() GrabServerCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(grabServerRequest(), cookie)
+	return GrabServerCookie(cookie)
+}
+
+// Write request to wire for GrabServer
+func grabServerRequest() []byte {
+	size := 4
 	b := 0
 	buf := make([]byte, size)
 
 	buf[b] = 36 // request opcode
 	b += 1
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request UngrabServer
-// size: 3
-// Write request to wire for UngrabServer
-func (c *Conn) UngrabServer() {
-	size := 3
-	b := 0
-	buf := make([]byte, size)
-
-	buf[b] = 37 // request opcode
-	b += 1
+// size: 4
+type UngrabServerCookie cookie
 
-	c.sendRequest(false, buf)
+// Write request to wire for UngrabServer
+func (c *Conn) UngrabServer() UngrabServerCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(ungrabServerRequest(), cookie)
+	return UngrabServerCookie(cookie)
 }
 
-// Request QueryPointer
-// size: 8
-func (c *Conn) QueryPointer(Window Id) (*QueryPointerReply, error) {
-	return c.QueryPointerReply(c.QueryPointerRequest(Window))
+func (c *Conn) UngrabServerChecked() UngrabServerCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(ungrabServerRequest(), cookie)
+	return UngrabServerCookie(cookie)
 }
 
-// Write request to wire for QueryPointer
-func (c *Conn) QueryPointerRequest(Window Id) *Cookie {
-	size := 8
+// Write request to wire for UngrabServer
+func ungrabServerRequest() []byte {
+	size := 4
 	b := 0
 	buf := make([]byte, size)
 
-	buf[b] = 38 // request opcode
+	buf[b] = 37 // request opcode
 	b += 1
 
-	b += 1 // padding
+	return buf
+}
 
-	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
-	b += 2
+// Request QueryPointer
+// size: 8
+type QueryPointerCookie cookie
 
-	Put32(buf[b:], uint32(Window))
-	b += 4
+func (c *Conn) QueryPointer(Window Id) QueryPointerCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(queryPointerRequest(Window), cookie)
+	return QueryPointerCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) QueryPointerUnchecked(Window Id) QueryPointerCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(queryPointerRequest(Window), cookie)
+	return QueryPointerCookie(cookie)
 }
 
 // Request reply for QueryPointer
@@ -7386,13 +8053,17 @@ type QueryPointerReply struct {
 	// padding: 2 bytes
 }
 
-// Read reply QueryPointer
-func (c *Conn) QueryPointerReply(cook *Cookie) (*QueryPointerReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request QueryPointer
+func (cook QueryPointerCookie) Reply() (*QueryPointerReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return queryPointerReply(buf), nil
+}
 
+// Read reply into structure from buffer for QueryPointer
+func queryPointerReply(buf []byte) *QueryPointerReply {
 	v := new(QueryPointerReply)
 	b := 1 // skip reply determinant
 
@@ -7432,22 +8103,16 @@ func (c *Conn) QueryPointerReply(cook *Cookie) (*QueryPointerReply, error) {
 
 	b += 2 // padding
 
-	return v, nil
-}
-
-// Request GetMotionEvents
-// size: 16
-func (c *Conn) GetMotionEvents(Window Id, Start Timestamp, Stop Timestamp) (*GetMotionEventsReply, error) {
-	return c.GetMotionEventsReply(c.GetMotionEventsRequest(Window, Start, Stop))
+	return v
 }
 
-// Write request to wire for GetMotionEvents
-func (c *Conn) GetMotionEventsRequest(Window Id, Start Timestamp, Stop Timestamp) *Cookie {
-	size := 16
+// Write request to wire for QueryPointer
+func queryPointerRequest(Window Id) []byte {
+	size := 8
 	b := 0
 	buf := make([]byte, size)
 
-	buf[b] = 39 // request opcode
+	buf[b] = 38 // request opcode
 	b += 1
 
 	b += 1 // padding
@@ -7458,13 +8123,23 @@ func (c *Conn) GetMotionEventsRequest(Window Id, Start Timestamp, Stop Timestamp
 	Put32(buf[b:], uint32(Window))
 	b += 4
 
-	Put32(buf[b:], uint32(Start))
-	b += 4
+	return buf
+}
 
-	Put32(buf[b:], uint32(Stop))
-	b += 4
+// Request GetMotionEvents
+// size: 16
+type GetMotionEventsCookie cookie
 
-	return c.sendRequest(true, buf)
+func (c *Conn) GetMotionEvents(Window Id, Start Timestamp, Stop Timestamp) GetMotionEventsCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(getMotionEventsRequest(Window, Start, Stop), cookie)
+	return GetMotionEventsCookie(cookie)
+}
+
+func (c *Conn) GetMotionEventsUnchecked(Window Id, Start Timestamp, Stop Timestamp) GetMotionEventsCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(getMotionEventsRequest(Window, Start, Stop), cookie)
+	return GetMotionEventsCookie(cookie)
 }
 
 // Request reply for GetMotionEvents
@@ -7478,13 +8153,17 @@ type GetMotionEventsReply struct {
 	Events []Timecoord // size: pad((int(EventsLen) * 8))
 }
 
-// Read reply GetMotionEvents
-func (c *Conn) GetMotionEventsReply(cook *Cookie) (*GetMotionEventsReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request GetMotionEvents
+func (cook GetMotionEventsCookie) Reply() (*GetMotionEventsReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return getMotionEventsReply(buf), nil
+}
 
+// Read reply into structure from buffer for GetMotionEvents
+func getMotionEventsReply(buf []byte) *GetMotionEventsReply {
 	v := new(GetMotionEventsReply)
 	b := 1 // skip reply determinant
 
@@ -7504,22 +8183,16 @@ func (c *Conn) GetMotionEventsReply(cook *Cookie) (*GetMotionEventsReply, error)
 	v.Events = make([]Timecoord, v.EventsLen)
 	b += ReadTimecoordList(buf[b:], v.Events)
 
-	return v, nil
-}
-
-// Request TranslateCoordinates
-// size: 16
-func (c *Conn) TranslateCoordinates(SrcWindow Id, DstWindow Id, SrcX int16, SrcY int16) (*TranslateCoordinatesReply, error) {
-	return c.TranslateCoordinatesReply(c.TranslateCoordinatesRequest(SrcWindow, DstWindow, SrcX, SrcY))
+	return v
 }
 
-// Write request to wire for TranslateCoordinates
-func (c *Conn) TranslateCoordinatesRequest(SrcWindow Id, DstWindow Id, SrcX int16, SrcY int16) *Cookie {
+// Write request to wire for GetMotionEvents
+func getMotionEventsRequest(Window Id, Start Timestamp, Stop Timestamp) []byte {
 	size := 16
 	b := 0
 	buf := make([]byte, size)
 
-	buf[b] = 40 // request opcode
+	buf[b] = 39 // request opcode
 	b += 1
 
 	b += 1 // padding
@@ -7527,19 +8200,32 @@ func (c *Conn) TranslateCoordinatesRequest(SrcWindow Id, DstWindow Id, SrcX int1
 	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
 	b += 2
 
-	Put32(buf[b:], uint32(SrcWindow))
+	Put32(buf[b:], uint32(Window))
 	b += 4
 
-	Put32(buf[b:], uint32(DstWindow))
+	Put32(buf[b:], uint32(Start))
 	b += 4
 
-	Put16(buf[b:], uint16(SrcX))
-	b += 2
+	Put32(buf[b:], uint32(Stop))
+	b += 4
 
-	Put16(buf[b:], uint16(SrcY))
-	b += 2
+	return buf
+}
+
+// Request TranslateCoordinates
+// size: 16
+type TranslateCoordinatesCookie cookie
 
-	return c.sendRequest(true, buf)
+func (c *Conn) TranslateCoordinates(SrcWindow Id, DstWindow Id, SrcX int16, SrcY int16) TranslateCoordinatesCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(translateCoordinatesRequest(SrcWindow, DstWindow, SrcX, SrcY), cookie)
+	return TranslateCoordinatesCookie(cookie)
+}
+
+func (c *Conn) TranslateCoordinatesUnchecked(SrcWindow Id, DstWindow Id, SrcX int16, SrcY int16) TranslateCoordinatesCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(translateCoordinatesRequest(SrcWindow, DstWindow, SrcX, SrcY), cookie)
+	return TranslateCoordinatesCookie(cookie)
 }
 
 // Request reply for TranslateCoordinates
@@ -7553,13 +8239,17 @@ type TranslateCoordinatesReply struct {
 	DstY       int16
 }
 
-// Read reply TranslateCoordinates
-func (c *Conn) TranslateCoordinatesReply(cook *Cookie) (*TranslateCoordinatesReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request TranslateCoordinates
+func (cook TranslateCoordinatesCookie) Reply() (*TranslateCoordinatesReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return translateCoordinatesReply(buf), nil
+}
 
+// Read reply into structure from buffer for TranslateCoordinates
+func translateCoordinatesReply(buf []byte) *TranslateCoordinatesReply {
 	v := new(TranslateCoordinatesReply)
 	b := 1 // skip reply determinant
 
@@ -7585,13 +8275,57 @@ func (c *Conn) TranslateCoordinatesReply(cook *Cookie) (*TranslateCoordinatesRep
 	v.DstY = int16(Get16(buf[b:]))
 	b += 2
 
-	return v, nil
+	return v
+}
+
+// Write request to wire for TranslateCoordinates
+func translateCoordinatesRequest(SrcWindow Id, DstWindow Id, SrcX int16, SrcY int16) []byte {
+	size := 16
+	b := 0
+	buf := make([]byte, size)
+
+	buf[b] = 40 // request opcode
+	b += 1
+
+	b += 1 // padding
+
+	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
+	b += 2
+
+	Put32(buf[b:], uint32(SrcWindow))
+	b += 4
+
+	Put32(buf[b:], uint32(DstWindow))
+	b += 4
+
+	Put16(buf[b:], uint16(SrcX))
+	b += 2
+
+	Put16(buf[b:], uint16(SrcY))
+	b += 2
+
+	return buf
 }
 
 // Request WarpPointer
 // size: 24
+type WarpPointerCookie cookie
+
 // Write request to wire for WarpPointer
-func (c *Conn) WarpPointer(SrcWindow Id, DstWindow Id, SrcX int16, SrcY int16, SrcWidth uint16, SrcHeight uint16, DstX int16, DstY int16) {
+func (c *Conn) WarpPointer(SrcWindow Id, DstWindow Id, SrcX int16, SrcY int16, SrcWidth uint16, SrcHeight uint16, DstX int16, DstY int16) WarpPointerCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(warpPointerRequest(SrcWindow, DstWindow, SrcX, SrcY, SrcWidth, SrcHeight, DstX, DstY), cookie)
+	return WarpPointerCookie(cookie)
+}
+
+func (c *Conn) WarpPointerChecked(SrcWindow Id, DstWindow Id, SrcX int16, SrcY int16, SrcWidth uint16, SrcHeight uint16, DstX int16, DstY int16) WarpPointerCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(warpPointerRequest(SrcWindow, DstWindow, SrcX, SrcY, SrcWidth, SrcHeight, DstX, DstY), cookie)
+	return WarpPointerCookie(cookie)
+}
+
+// Write request to wire for WarpPointer
+func warpPointerRequest(SrcWindow Id, DstWindow Id, SrcX int16, SrcY int16, SrcWidth uint16, SrcHeight uint16, DstX int16, DstY int16) []byte {
 	size := 24
 	b := 0
 	buf := make([]byte, size)
@@ -7628,13 +8362,28 @@ func (c *Conn) WarpPointer(SrcWindow Id, DstWindow Id, SrcX int16, SrcY int16, S
 	Put16(buf[b:], uint16(DstY))
 	b += 2
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request SetInputFocus
 // size: 12
+type SetInputFocusCookie cookie
+
 // Write request to wire for SetInputFocus
-func (c *Conn) SetInputFocus(RevertTo byte, Focus Id, Time Timestamp) {
+func (c *Conn) SetInputFocus(RevertTo byte, Focus Id, Time Timestamp) SetInputFocusCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(setInputFocusRequest(RevertTo, Focus, Time), cookie)
+	return SetInputFocusCookie(cookie)
+}
+
+func (c *Conn) SetInputFocusChecked(RevertTo byte, Focus Id, Time Timestamp) SetInputFocusCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(setInputFocusRequest(RevertTo, Focus, Time), cookie)
+	return SetInputFocusCookie(cookie)
+}
+
+// Write request to wire for SetInputFocus
+func setInputFocusRequest(RevertTo byte, Focus Id, Time Timestamp) []byte {
 	size := 12
 	b := 0
 	buf := make([]byte, size)
@@ -7654,25 +8403,23 @@ func (c *Conn) SetInputFocus(RevertTo byte, Focus Id, Time Timestamp) {
 	Put32(buf[b:], uint32(Time))
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request GetInputFocus
-// size: 3
-func (c *Conn) GetInputFocus() (*GetInputFocusReply, error) {
-	return c.GetInputFocusReply(c.GetInputFocusRequest())
-}
-
-// Write request to wire for GetInputFocus
-func (c *Conn) GetInputFocusRequest() *Cookie {
-	size := 3
-	b := 0
-	buf := make([]byte, size)
+// size: 4
+type GetInputFocusCookie cookie
 
-	buf[b] = 43 // request opcode
-	b += 1
+func (c *Conn) GetInputFocus() GetInputFocusCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(getInputFocusRequest(), cookie)
+	return GetInputFocusCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) GetInputFocusUnchecked() GetInputFocusCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(getInputFocusRequest(), cookie)
+	return GetInputFocusCookie(cookie)
 }
 
 // Request reply for GetInputFocus
@@ -7684,13 +8431,17 @@ type GetInputFocusReply struct {
 	Focus    Id
 }
 
-// Read reply GetInputFocus
-func (c *Conn) GetInputFocusReply(cook *Cookie) (*GetInputFocusReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request GetInputFocus
+func (cook GetInputFocusCookie) Reply() (*GetInputFocusReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return getInputFocusReply(buf), nil
+}
 
+// Read reply into structure from buffer for GetInputFocus
+func getInputFocusReply(buf []byte) *GetInputFocusReply {
 	v := new(GetInputFocusReply)
 	b := 1 // skip reply determinant
 
@@ -7706,25 +8457,35 @@ func (c *Conn) GetInputFocusReply(cook *Cookie) (*GetInputFocusReply, error) {
 	v.Focus = Id(Get32(buf[b:]))
 	b += 4
 
-	return v, nil
-}
-
-// Request QueryKeymap
-// size: 3
-func (c *Conn) QueryKeymap() (*QueryKeymapReply, error) {
-	return c.QueryKeymapReply(c.QueryKeymapRequest())
+	return v
 }
 
-// Write request to wire for QueryKeymap
-func (c *Conn) QueryKeymapRequest() *Cookie {
-	size := 3
+// Write request to wire for GetInputFocus
+func getInputFocusRequest() []byte {
+	size := 4
 	b := 0
 	buf := make([]byte, size)
 
-	buf[b] = 44 // request opcode
+	buf[b] = 43 // request opcode
 	b += 1
 
-	return c.sendRequest(true, buf)
+	return buf
+}
+
+// Request QueryKeymap
+// size: 4
+type QueryKeymapCookie cookie
+
+func (c *Conn) QueryKeymap() QueryKeymapCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(queryKeymapRequest(), cookie)
+	return QueryKeymapCookie(cookie)
+}
+
+func (c *Conn) QueryKeymapUnchecked() QueryKeymapCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(queryKeymapRequest(), cookie)
+	return QueryKeymapCookie(cookie)
 }
 
 // Request reply for QueryKeymap
@@ -7736,13 +8497,17 @@ type QueryKeymapReply struct {
 	Keys []byte // size: pad(32)
 }
 
-// Read reply QueryKeymap
-func (c *Conn) QueryKeymapReply(cook *Cookie) (*QueryKeymapReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request QueryKeymap
+func (cook QueryKeymapCookie) Reply() (*QueryKeymapReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return queryKeymapReply(buf), nil
+}
 
+// Read reply into structure from buffer for QueryKeymap
+func queryKeymapReply(buf []byte) *QueryKeymapReply {
 	v := new(QueryKeymapReply)
 	b := 1 // skip reply determinant
 
@@ -7758,14 +8523,41 @@ func (c *Conn) QueryKeymapReply(cook *Cookie) (*QueryKeymapReply, error) {
 	copy(v.Keys[:32], buf[b:])
 	b += pad(int(32))
 
-	return v, nil
+	return v
+}
+
+// Write request to wire for QueryKeymap
+func queryKeymapRequest() []byte {
+	size := 4
+	b := 0
+	buf := make([]byte, size)
+
+	buf[b] = 44 // request opcode
+	b += 1
+
+	return buf
 }
 
 // Request OpenFont
-// size: (12 + pad((int(NameLen) * 1)))
+// size: pad((12 + pad((int(NameLen) * 1))))
+type OpenFontCookie cookie
+
 // Write request to wire for OpenFont
-func (c *Conn) OpenFont(Fid Id, NameLen uint16, Name string) {
-	size := (12 + pad((int(NameLen) * 1)))
+func (c *Conn) OpenFont(Fid Id, NameLen uint16, Name string) OpenFontCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(openFontRequest(Fid, NameLen, Name), cookie)
+	return OpenFontCookie(cookie)
+}
+
+func (c *Conn) OpenFontChecked(Fid Id, NameLen uint16, Name string) OpenFontCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(openFontRequest(Fid, NameLen, Name), cookie)
+	return OpenFontCookie(cookie)
+}
+
+// Write request to wire for OpenFont
+func openFontRequest(Fid Id, NameLen uint16, Name string) []byte {
+	size := pad((12 + pad((int(NameLen) * 1))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -7788,13 +8580,28 @@ func (c *Conn) OpenFont(Fid Id, NameLen uint16, Name string) {
 	copy(buf[b:], Name[:NameLen])
 	b += pad(int(NameLen))
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request CloseFont
 // size: 8
+type CloseFontCookie cookie
+
 // Write request to wire for CloseFont
-func (c *Conn) CloseFont(Font Id) {
+func (c *Conn) CloseFont(Font Id) CloseFontCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(closeFontRequest(Font), cookie)
+	return CloseFontCookie(cookie)
+}
+
+func (c *Conn) CloseFontChecked(Font Id) CloseFontCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(closeFontRequest(Font), cookie)
+	return CloseFontCookie(cookie)
+}
+
+// Write request to wire for CloseFont
+func closeFontRequest(Font Id) []byte {
 	size := 8
 	b := 0
 	buf := make([]byte, size)
@@ -7810,33 +8617,23 @@ func (c *Conn) CloseFont(Font Id) {
 	Put32(buf[b:], uint32(Font))
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request QueryFont
 // size: 8
-func (c *Conn) QueryFont(Font Id) (*QueryFontReply, error) {
-	return c.QueryFontReply(c.QueryFontRequest(Font))
-}
-
-// Write request to wire for QueryFont
-func (c *Conn) QueryFontRequest(Font Id) *Cookie {
-	size := 8
-	b := 0
-	buf := make([]byte, size)
+type QueryFontCookie cookie
 
-	buf[b] = 47 // request opcode
-	b += 1
-
-	b += 1 // padding
-
-	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
-	b += 2
-
-	Put32(buf[b:], uint32(Font))
-	b += 4
+func (c *Conn) QueryFont(Font Id) QueryFontCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(queryFontRequest(Font), cookie)
+	return QueryFontCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) QueryFontUnchecked(Font Id) QueryFontCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(queryFontRequest(Font), cookie)
+	return QueryFontCookie(cookie)
 }
 
 // Request reply for QueryFont
@@ -7864,13 +8661,17 @@ type QueryFontReply struct {
 	CharInfos      []Charinfo // size: pad((int(CharInfosLen) * 12))
 }
 
-// Read reply QueryFont
-func (c *Conn) QueryFontReply(cook *Cookie) (*QueryFontReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request QueryFont
+func (cook QueryFontCookie) Reply() (*QueryFontReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return queryFontReply(buf), nil
+}
 
+// Read reply into structure from buffer for QueryFont
+func queryFontReply(buf []byte) *QueryFontReply {
 	v := new(QueryFontReply)
 	b := 1 // skip reply determinant
 
@@ -7935,26 +8736,19 @@ func (c *Conn) QueryFontReply(cook *Cookie) (*QueryFontReply, error) {
 	v.CharInfos = make([]Charinfo, v.CharInfosLen)
 	b += ReadCharinfoList(buf[b:], v.CharInfos)
 
-	return v, nil
-}
-
-// Request QueryTextExtents
-// size: (8 + pad((len(String) * 2)))
-func (c *Conn) QueryTextExtents(Font Id, String []Char2b, StringLen uint16) (*QueryTextExtentsReply, error) {
-	return c.QueryTextExtentsReply(c.QueryTextExtentsRequest(Font, String, StringLen))
+	return v
 }
 
-// Write request to wire for QueryTextExtents
-func (c *Conn) QueryTextExtentsRequest(Font Id, String []Char2b, StringLen uint16) *Cookie {
-	size := (8 + pad((len(String) * 2)))
+// Write request to wire for QueryFont
+func queryFontRequest(Font Id) []byte {
+	size := 8
 	b := 0
 	buf := make([]byte, size)
 
-	buf[b] = 48 // request opcode
+	buf[b] = 47 // request opcode
 	b += 1
 
-	buf[b] = byte((int(StringLen) & 1))
-	b += 1
+	b += 1 // padding
 
 	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
 	b += 2
@@ -7962,11 +8756,23 @@ func (c *Conn) QueryTextExtentsRequest(Font Id, String []Char2b, StringLen uint1
 	Put32(buf[b:], uint32(Font))
 	b += 4
 
-	b += Char2bListBytes(buf[b:], String)
+	return buf
+}
 
-	// skip writing local field: StringLen (2) :: uint16
+// Request QueryTextExtents
+// size: pad((8 + pad((len(String) * 2))))
+type QueryTextExtentsCookie cookie
+
+func (c *Conn) QueryTextExtents(Font Id, String []Char2b, StringLen uint16) QueryTextExtentsCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(queryTextExtentsRequest(Font, String, StringLen), cookie)
+	return QueryTextExtentsCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) QueryTextExtentsUnchecked(Font Id, String []Char2b, StringLen uint16) QueryTextExtentsCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(queryTextExtentsRequest(Font, String, StringLen), cookie)
+	return QueryTextExtentsCookie(cookie)
 }
 
 // Request reply for QueryTextExtents
@@ -7984,13 +8790,17 @@ type QueryTextExtentsReply struct {
 	OverallRight   int32
 }
 
-// Read reply QueryTextExtents
-func (c *Conn) QueryTextExtentsReply(cook *Cookie) (*QueryTextExtentsReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request QueryTextExtents
+func (cook QueryTextExtentsCookie) Reply() (*QueryTextExtentsReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return queryTextExtentsReply(buf), nil
+}
 
+// Read reply into structure from buffer for QueryTextExtents
+func queryTextExtentsReply(buf []byte) *QueryTextExtentsReply {
 	v := new(QueryTextExtentsReply)
 	b := 1 // skip reply determinant
 
@@ -8024,39 +8834,48 @@ func (c *Conn) QueryTextExtentsReply(cook *Cookie) (*QueryTextExtentsReply, erro
 	v.OverallRight = int32(Get32(buf[b:]))
 	b += 4
 
-	return v, nil
-}
-
-// Request ListFonts
-// size: (8 + pad((int(PatternLen) * 1)))
-func (c *Conn) ListFonts(MaxNames uint16, PatternLen uint16, Pattern string) (*ListFontsReply, error) {
-	return c.ListFontsReply(c.ListFontsRequest(MaxNames, PatternLen, Pattern))
+	return v
 }
 
-// Write request to wire for ListFonts
-func (c *Conn) ListFontsRequest(MaxNames uint16, PatternLen uint16, Pattern string) *Cookie {
-	size := (8 + pad((int(PatternLen) * 1)))
+// Write request to wire for QueryTextExtents
+func queryTextExtentsRequest(Font Id, String []Char2b, StringLen uint16) []byte {
+	size := pad((8 + pad((len(String) * 2))))
 	b := 0
 	buf := make([]byte, size)
 
-	buf[b] = 49 // request opcode
+	buf[b] = 48 // request opcode
 	b += 1
 
-	b += 1 // padding
+	buf[b] = byte((int(StringLen) & 1))
+	b += 1
 
 	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
 	b += 2
 
-	Put16(buf[b:], MaxNames)
-	b += 2
+	Put32(buf[b:], uint32(Font))
+	b += 4
 
-	Put16(buf[b:], PatternLen)
-	b += 2
+	b += Char2bListBytes(buf[b:], String)
 
-	copy(buf[b:], Pattern[:PatternLen])
-	b += pad(int(PatternLen))
+	// skip writing local field: StringLen (2) :: uint16
 
-	return c.sendRequest(true, buf)
+	return buf
+}
+
+// Request ListFonts
+// size: pad((8 + pad((int(PatternLen) * 1))))
+type ListFontsCookie cookie
+
+func (c *Conn) ListFonts(MaxNames uint16, PatternLen uint16, Pattern string) ListFontsCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(listFontsRequest(MaxNames, PatternLen, Pattern), cookie)
+	return ListFontsCookie(cookie)
+}
+
+func (c *Conn) ListFontsUnchecked(MaxNames uint16, PatternLen uint16, Pattern string) ListFontsCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(listFontsRequest(MaxNames, PatternLen, Pattern), cookie)
+	return ListFontsCookie(cookie)
 }
 
 // Request reply for ListFonts
@@ -8070,13 +8889,17 @@ type ListFontsReply struct {
 	Names []Str // size: StrListSize(Names)
 }
 
-// Read reply ListFonts
-func (c *Conn) ListFontsReply(cook *Cookie) (*ListFontsReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request ListFonts
+func (cook ListFontsCookie) Reply() (*ListFontsReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return listFontsReply(buf), nil
+}
 
+// Read reply into structure from buffer for ListFonts
+func listFontsReply(buf []byte) *ListFontsReply {
 	v := new(ListFontsReply)
 	b := 1 // skip reply determinant
 
@@ -8096,22 +8919,16 @@ func (c *Conn) ListFontsReply(cook *Cookie) (*ListFontsReply, error) {
 	v.Names = make([]Str, v.NamesLen)
 	b += ReadStrList(buf[b:], v.Names)
 
-	return v, nil
-}
-
-// Request ListFontsWithInfo
-// size: (8 + pad((int(PatternLen) * 1)))
-func (c *Conn) ListFontsWithInfo(MaxNames uint16, PatternLen uint16, Pattern string) (*ListFontsWithInfoReply, error) {
-	return c.ListFontsWithInfoReply(c.ListFontsWithInfoRequest(MaxNames, PatternLen, Pattern))
+	return v
 }
 
-// Write request to wire for ListFontsWithInfo
-func (c *Conn) ListFontsWithInfoRequest(MaxNames uint16, PatternLen uint16, Pattern string) *Cookie {
-	size := (8 + pad((int(PatternLen) * 1)))
+// Write request to wire for ListFonts
+func listFontsRequest(MaxNames uint16, PatternLen uint16, Pattern string) []byte {
+	size := pad((8 + pad((int(PatternLen) * 1))))
 	b := 0
 	buf := make([]byte, size)
 
-	buf[b] = 50 // request opcode
+	buf[b] = 49 // request opcode
 	b += 1
 
 	b += 1 // padding
@@ -8128,7 +8945,23 @@ func (c *Conn) ListFontsWithInfoRequest(MaxNames uint16, PatternLen uint16, Patt
 	copy(buf[b:], Pattern[:PatternLen])
 	b += pad(int(PatternLen))
 
-	return c.sendRequest(true, buf)
+	return buf
+}
+
+// Request ListFontsWithInfo
+// size: pad((8 + pad((int(PatternLen) * 1))))
+type ListFontsWithInfoCookie cookie
+
+func (c *Conn) ListFontsWithInfo(MaxNames uint16, PatternLen uint16, Pattern string) ListFontsWithInfoCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(listFontsWithInfoRequest(MaxNames, PatternLen, Pattern), cookie)
+	return ListFontsWithInfoCookie(cookie)
+}
+
+func (c *Conn) ListFontsWithInfoUnchecked(MaxNames uint16, PatternLen uint16, Pattern string) ListFontsWithInfoCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(listFontsWithInfoRequest(MaxNames, PatternLen, Pattern), cookie)
+	return ListFontsWithInfoCookie(cookie)
 }
 
 // Request reply for ListFontsWithInfo
@@ -8156,13 +8989,17 @@ type ListFontsWithInfoReply struct {
 	Name           string     // size: pad((int(NameLen) * 1))
 }
 
-// Read reply ListFontsWithInfo
-func (c *Conn) ListFontsWithInfoReply(cook *Cookie) (*ListFontsWithInfoReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request ListFontsWithInfo
+func (cook ListFontsWithInfoCookie) Reply() (*ListFontsWithInfoReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return listFontsWithInfoReply(buf), nil
+}
 
+// Read reply into structure from buffer for ListFontsWithInfo
+func listFontsWithInfoReply(buf []byte) *ListFontsWithInfoReply {
 	v := new(ListFontsWithInfoReply)
 	b := 1 // skip reply determinant
 
@@ -8232,14 +9069,55 @@ func (c *Conn) ListFontsWithInfoReply(cook *Cookie) (*ListFontsWithInfoReply, er
 		b += pad(int(v.NameLen))
 	}
 
-	return v, nil
+	return v
+}
+
+// Write request to wire for ListFontsWithInfo
+func listFontsWithInfoRequest(MaxNames uint16, PatternLen uint16, Pattern string) []byte {
+	size := pad((8 + pad((int(PatternLen) * 1))))
+	b := 0
+	buf := make([]byte, size)
+
+	buf[b] = 50 // request opcode
+	b += 1
+
+	b += 1 // padding
+
+	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
+	b += 2
+
+	Put16(buf[b:], MaxNames)
+	b += 2
+
+	Put16(buf[b:], PatternLen)
+	b += 2
+
+	copy(buf[b:], Pattern[:PatternLen])
+	b += pad(int(PatternLen))
+
+	return buf
 }
 
 // Request SetFontPath
-// size: (8 + StrListSize(Font))
+// size: pad((8 + StrListSize(Font)))
+type SetFontPathCookie cookie
+
+// Write request to wire for SetFontPath
+func (c *Conn) SetFontPath(FontQty uint16, Font []Str) SetFontPathCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(setFontPathRequest(FontQty, Font), cookie)
+	return SetFontPathCookie(cookie)
+}
+
+func (c *Conn) SetFontPathChecked(FontQty uint16, Font []Str) SetFontPathCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(setFontPathRequest(FontQty, Font), cookie)
+	return SetFontPathCookie(cookie)
+}
+
 // Write request to wire for SetFontPath
-func (c *Conn) SetFontPath(FontQty uint16, Font []Str) {
-	size := (8 + StrListSize(Font))
+func setFontPathRequest(FontQty uint16, Font []Str) []byte {
+	size := pad((8 + StrListSize(Font)))
 	b := 0
 	buf := make([]byte, size)
 
@@ -8258,25 +9136,23 @@ func (c *Conn) SetFontPath(FontQty uint16, Font []Str) {
 
 	b += StrListBytes(buf[b:], Font)
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request GetFontPath
-// size: 3
-func (c *Conn) GetFontPath() (*GetFontPathReply, error) {
-	return c.GetFontPathReply(c.GetFontPathRequest())
-}
-
-// Write request to wire for GetFontPath
-func (c *Conn) GetFontPathRequest() *Cookie {
-	size := 3
-	b := 0
-	buf := make([]byte, size)
+// size: 4
+type GetFontPathCookie cookie
 
-	buf[b] = 52 // request opcode
-	b += 1
+func (c *Conn) GetFontPath() GetFontPathCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(getFontPathRequest(), cookie)
+	return GetFontPathCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) GetFontPathUnchecked() GetFontPathCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(getFontPathRequest(), cookie)
+	return GetFontPathCookie(cookie)
 }
 
 // Request reply for GetFontPath
@@ -8290,13 +9166,17 @@ type GetFontPathReply struct {
 	Path []Str // size: StrListSize(Path)
 }
 
-// Read reply GetFontPath
-func (c *Conn) GetFontPathReply(cook *Cookie) (*GetFontPathReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request GetFontPath
+func (cook GetFontPathCookie) Reply() (*GetFontPathReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return getFontPathReply(buf), nil
+}
 
+// Read reply into structure from buffer for GetFontPath
+func getFontPathReply(buf []byte) *GetFontPathReply {
 	v := new(GetFontPathReply)
 	b := 1 // skip reply determinant
 
@@ -8316,13 +9196,40 @@ func (c *Conn) GetFontPathReply(cook *Cookie) (*GetFontPathReply, error) {
 	v.Path = make([]Str, v.PathLen)
 	b += ReadStrList(buf[b:], v.Path)
 
-	return v, nil
+	return v
+}
+
+// Write request to wire for GetFontPath
+func getFontPathRequest() []byte {
+	size := 4
+	b := 0
+	buf := make([]byte, size)
+
+	buf[b] = 52 // request opcode
+	b += 1
+
+	return buf
 }
 
 // Request CreatePixmap
 // size: 16
+type CreatePixmapCookie cookie
+
 // Write request to wire for CreatePixmap
-func (c *Conn) CreatePixmap(Depth byte, Pid Id, Drawable Id, Width uint16, Height uint16) {
+func (c *Conn) CreatePixmap(Depth byte, Pid Id, Drawable Id, Width uint16, Height uint16) CreatePixmapCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(createPixmapRequest(Depth, Pid, Drawable, Width, Height), cookie)
+	return CreatePixmapCookie(cookie)
+}
+
+func (c *Conn) CreatePixmapChecked(Depth byte, Pid Id, Drawable Id, Width uint16, Height uint16) CreatePixmapCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(createPixmapRequest(Depth, Pid, Drawable, Width, Height), cookie)
+	return CreatePixmapCookie(cookie)
+}
+
+// Write request to wire for CreatePixmap
+func createPixmapRequest(Depth byte, Pid Id, Drawable Id, Width uint16, Height uint16) []byte {
 	size := 16
 	b := 0
 	buf := make([]byte, size)
@@ -8348,13 +9255,28 @@ func (c *Conn) CreatePixmap(Depth byte, Pid Id, Drawable Id, Width uint16, Heigh
 	Put16(buf[b:], Height)
 	b += 2
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request FreePixmap
 // size: 8
+type FreePixmapCookie cookie
+
 // Write request to wire for FreePixmap
-func (c *Conn) FreePixmap(Pixmap Id) {
+func (c *Conn) FreePixmap(Pixmap Id) FreePixmapCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(freePixmapRequest(Pixmap), cookie)
+	return FreePixmapCookie(cookie)
+}
+
+func (c *Conn) FreePixmapChecked(Pixmap Id) FreePixmapCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(freePixmapRequest(Pixmap), cookie)
+	return FreePixmapCookie(cookie)
+}
+
+// Write request to wire for FreePixmap
+func freePixmapRequest(Pixmap Id) []byte {
 	size := 8
 	b := 0
 	buf := make([]byte, size)
@@ -8370,14 +9292,29 @@ func (c *Conn) FreePixmap(Pixmap Id) {
 	Put32(buf[b:], uint32(Pixmap))
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request CreateGC
-// size: (12 + (4 + pad((4 * popCount(int(ValueMask))))))
+// size: pad((12 + (4 + pad((4 * popCount(int(ValueMask)))))))
+type CreateGCCookie cookie
+
+// Write request to wire for CreateGC
+func (c *Conn) CreateGC(Cid Id, Drawable Id, ValueMask uint32, ValueList []uint32) CreateGCCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(createGCRequest(Cid, Drawable, ValueMask, ValueList), cookie)
+	return CreateGCCookie(cookie)
+}
+
+func (c *Conn) CreateGCChecked(Cid Id, Drawable Id, ValueMask uint32, ValueList []uint32) CreateGCCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(createGCRequest(Cid, Drawable, ValueMask, ValueList), cookie)
+	return CreateGCCookie(cookie)
+}
+
 // Write request to wire for CreateGC
-func (c *Conn) CreateGC(Cid Id, Drawable Id, ValueMask uint32, ValueList []uint32) {
-	size := (12 + (4 + pad((4 * popCount(int(ValueMask))))))
+func createGCRequest(Cid Id, Drawable Id, ValueMask uint32, ValueList []uint32) []byte {
+	size := pad((12 + (4 + pad((4 * popCount(int(ValueMask)))))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -8403,14 +9340,29 @@ func (c *Conn) CreateGC(Cid Id, Drawable Id, ValueMask uint32, ValueList []uint3
 	}
 	b = pad(b)
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request ChangeGC
-// size: (8 + (4 + pad((4 * popCount(int(ValueMask))))))
+// size: pad((8 + (4 + pad((4 * popCount(int(ValueMask)))))))
+type ChangeGCCookie cookie
+
+// Write request to wire for ChangeGC
+func (c *Conn) ChangeGC(Gc Id, ValueMask uint32, ValueList []uint32) ChangeGCCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(changeGCRequest(Gc, ValueMask, ValueList), cookie)
+	return ChangeGCCookie(cookie)
+}
+
+func (c *Conn) ChangeGCChecked(Gc Id, ValueMask uint32, ValueList []uint32) ChangeGCCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(changeGCRequest(Gc, ValueMask, ValueList), cookie)
+	return ChangeGCCookie(cookie)
+}
+
 // Write request to wire for ChangeGC
-func (c *Conn) ChangeGC(Gc Id, ValueMask uint32, ValueList []uint32) {
-	size := (8 + (4 + pad((4 * popCount(int(ValueMask))))))
+func changeGCRequest(Gc Id, ValueMask uint32, ValueList []uint32) []byte {
+	size := pad((8 + (4 + pad((4 * popCount(int(ValueMask)))))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -8433,13 +9385,28 @@ func (c *Conn) ChangeGC(Gc Id, ValueMask uint32, ValueList []uint32) {
 	}
 	b = pad(b)
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request CopyGC
 // size: 16
+type CopyGCCookie cookie
+
 // Write request to wire for CopyGC
-func (c *Conn) CopyGC(SrcGc Id, DstGc Id, ValueMask uint32) {
+func (c *Conn) CopyGC(SrcGc Id, DstGc Id, ValueMask uint32) CopyGCCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(copyGCRequest(SrcGc, DstGc, ValueMask), cookie)
+	return CopyGCCookie(cookie)
+}
+
+func (c *Conn) CopyGCChecked(SrcGc Id, DstGc Id, ValueMask uint32) CopyGCCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(copyGCRequest(SrcGc, DstGc, ValueMask), cookie)
+	return CopyGCCookie(cookie)
+}
+
+// Write request to wire for CopyGC
+func copyGCRequest(SrcGc Id, DstGc Id, ValueMask uint32) []byte {
 	size := 16
 	b := 0
 	buf := make([]byte, size)
@@ -8461,14 +9428,29 @@ func (c *Conn) CopyGC(SrcGc Id, DstGc Id, ValueMask uint32) {
 	Put32(buf[b:], ValueMask)
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request SetDashes
-// size: (12 + pad((int(DashesLen) * 1)))
+// size: pad((12 + pad((int(DashesLen) * 1))))
+type SetDashesCookie cookie
+
 // Write request to wire for SetDashes
-func (c *Conn) SetDashes(Gc Id, DashOffset uint16, DashesLen uint16, Dashes []byte) {
-	size := (12 + pad((int(DashesLen) * 1)))
+func (c *Conn) SetDashes(Gc Id, DashOffset uint16, DashesLen uint16, Dashes []byte) SetDashesCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(setDashesRequest(Gc, DashOffset, DashesLen, Dashes), cookie)
+	return SetDashesCookie(cookie)
+}
+
+func (c *Conn) SetDashesChecked(Gc Id, DashOffset uint16, DashesLen uint16, Dashes []byte) SetDashesCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(setDashesRequest(Gc, DashOffset, DashesLen, Dashes), cookie)
+	return SetDashesCookie(cookie)
+}
+
+// Write request to wire for SetDashes
+func setDashesRequest(Gc Id, DashOffset uint16, DashesLen uint16, Dashes []byte) []byte {
+	size := pad((12 + pad((int(DashesLen) * 1))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -8492,14 +9474,29 @@ func (c *Conn) SetDashes(Gc Id, DashOffset uint16, DashesLen uint16, Dashes []by
 	copy(buf[b:], Dashes[:DashesLen])
 	b += pad(int(DashesLen))
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request SetClipRectangles
-// size: (12 + pad((len(Rectangles) * 8)))
+// size: pad((12 + pad((len(Rectangles) * 8))))
+type SetClipRectanglesCookie cookie
+
 // Write request to wire for SetClipRectangles
-func (c *Conn) SetClipRectangles(Ordering byte, Gc Id, ClipXOrigin int16, ClipYOrigin int16, Rectangles []Rectangle) {
-	size := (12 + pad((len(Rectangles) * 8)))
+func (c *Conn) SetClipRectangles(Ordering byte, Gc Id, ClipXOrigin int16, ClipYOrigin int16, Rectangles []Rectangle) SetClipRectanglesCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(setClipRectanglesRequest(Ordering, Gc, ClipXOrigin, ClipYOrigin, Rectangles), cookie)
+	return SetClipRectanglesCookie(cookie)
+}
+
+func (c *Conn) SetClipRectanglesChecked(Ordering byte, Gc Id, ClipXOrigin int16, ClipYOrigin int16, Rectangles []Rectangle) SetClipRectanglesCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(setClipRectanglesRequest(Ordering, Gc, ClipXOrigin, ClipYOrigin, Rectangles), cookie)
+	return SetClipRectanglesCookie(cookie)
+}
+
+// Write request to wire for SetClipRectangles
+func setClipRectanglesRequest(Ordering byte, Gc Id, ClipXOrigin int16, ClipYOrigin int16, Rectangles []Rectangle) []byte {
+	size := pad((12 + pad((len(Rectangles) * 8))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -8523,13 +9520,28 @@ func (c *Conn) SetClipRectangles(Ordering byte, Gc Id, ClipXOrigin int16, ClipYO
 
 	b += RectangleListBytes(buf[b:], Rectangles)
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request FreeGC
 // size: 8
+type FreeGCCookie cookie
+
+// Write request to wire for FreeGC
+func (c *Conn) FreeGC(Gc Id) FreeGCCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(freeGCRequest(Gc), cookie)
+	return FreeGCCookie(cookie)
+}
+
+func (c *Conn) FreeGCChecked(Gc Id) FreeGCCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(freeGCRequest(Gc), cookie)
+	return FreeGCCookie(cookie)
+}
+
 // Write request to wire for FreeGC
-func (c *Conn) FreeGC(Gc Id) {
+func freeGCRequest(Gc Id) []byte {
 	size := 8
 	b := 0
 	buf := make([]byte, size)
@@ -8545,13 +9557,28 @@ func (c *Conn) FreeGC(Gc Id) {
 	Put32(buf[b:], uint32(Gc))
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request ClearArea
 // size: 16
+type ClearAreaCookie cookie
+
+// Write request to wire for ClearArea
+func (c *Conn) ClearArea(Exposures bool, Window Id, X int16, Y int16, Width uint16, Height uint16) ClearAreaCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(clearAreaRequest(Exposures, Window, X, Y, Width, Height), cookie)
+	return ClearAreaCookie(cookie)
+}
+
+func (c *Conn) ClearAreaChecked(Exposures bool, Window Id, X int16, Y int16, Width uint16, Height uint16) ClearAreaCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(clearAreaRequest(Exposures, Window, X, Y, Width, Height), cookie)
+	return ClearAreaCookie(cookie)
+}
+
 // Write request to wire for ClearArea
-func (c *Conn) ClearArea(Exposures bool, Window Id, X int16, Y int16, Width uint16, Height uint16) {
+func clearAreaRequest(Exposures bool, Window Id, X int16, Y int16, Width uint16, Height uint16) []byte {
 	size := 16
 	b := 0
 	buf := make([]byte, size)
@@ -8584,13 +9611,28 @@ func (c *Conn) ClearArea(Exposures bool, Window Id, X int16, Y int16, Width uint
 	Put16(buf[b:], Height)
 	b += 2
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request CopyArea
 // size: 28
+type CopyAreaCookie cookie
+
+// Write request to wire for CopyArea
+func (c *Conn) CopyArea(SrcDrawable Id, DstDrawable Id, Gc Id, SrcX int16, SrcY int16, DstX int16, DstY int16, Width uint16, Height uint16) CopyAreaCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(copyAreaRequest(SrcDrawable, DstDrawable, Gc, SrcX, SrcY, DstX, DstY, Width, Height), cookie)
+	return CopyAreaCookie(cookie)
+}
+
+func (c *Conn) CopyAreaChecked(SrcDrawable Id, DstDrawable Id, Gc Id, SrcX int16, SrcY int16, DstX int16, DstY int16, Width uint16, Height uint16) CopyAreaCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(copyAreaRequest(SrcDrawable, DstDrawable, Gc, SrcX, SrcY, DstX, DstY, Width, Height), cookie)
+	return CopyAreaCookie(cookie)
+}
+
 // Write request to wire for CopyArea
-func (c *Conn) CopyArea(SrcDrawable Id, DstDrawable Id, Gc Id, SrcX int16, SrcY int16, DstX int16, DstY int16, Width uint16, Height uint16) {
+func copyAreaRequest(SrcDrawable Id, DstDrawable Id, Gc Id, SrcX int16, SrcY int16, DstX int16, DstY int16, Width uint16, Height uint16) []byte {
 	size := 28
 	b := 0
 	buf := make([]byte, size)
@@ -8630,13 +9672,28 @@ func (c *Conn) CopyArea(SrcDrawable Id, DstDrawable Id, Gc Id, SrcX int16, SrcY
 	Put16(buf[b:], Height)
 	b += 2
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request CopyPlane
 // size: 32
+type CopyPlaneCookie cookie
+
 // Write request to wire for CopyPlane
-func (c *Conn) CopyPlane(SrcDrawable Id, DstDrawable Id, Gc Id, SrcX int16, SrcY int16, DstX int16, DstY int16, Width uint16, Height uint16, BitPlane uint32) {
+func (c *Conn) CopyPlane(SrcDrawable Id, DstDrawable Id, Gc Id, SrcX int16, SrcY int16, DstX int16, DstY int16, Width uint16, Height uint16, BitPlane uint32) CopyPlaneCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(copyPlaneRequest(SrcDrawable, DstDrawable, Gc, SrcX, SrcY, DstX, DstY, Width, Height, BitPlane), cookie)
+	return CopyPlaneCookie(cookie)
+}
+
+func (c *Conn) CopyPlaneChecked(SrcDrawable Id, DstDrawable Id, Gc Id, SrcX int16, SrcY int16, DstX int16, DstY int16, Width uint16, Height uint16, BitPlane uint32) CopyPlaneCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(copyPlaneRequest(SrcDrawable, DstDrawable, Gc, SrcX, SrcY, DstX, DstY, Width, Height, BitPlane), cookie)
+	return CopyPlaneCookie(cookie)
+}
+
+// Write request to wire for CopyPlane
+func copyPlaneRequest(SrcDrawable Id, DstDrawable Id, Gc Id, SrcX int16, SrcY int16, DstX int16, DstY int16, Width uint16, Height uint16, BitPlane uint32) []byte {
 	size := 32
 	b := 0
 	buf := make([]byte, size)
@@ -8679,14 +9736,29 @@ func (c *Conn) CopyPlane(SrcDrawable Id, DstDrawable Id, Gc Id, SrcX int16, SrcY
 	Put32(buf[b:], BitPlane)
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request PolyPoint
-// size: (12 + pad((len(Points) * 4)))
+// size: pad((12 + pad((len(Points) * 4))))
+type PolyPointCookie cookie
+
+// Write request to wire for PolyPoint
+func (c *Conn) PolyPoint(CoordinateMode byte, Drawable Id, Gc Id, Points []Point) PolyPointCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(polyPointRequest(CoordinateMode, Drawable, Gc, Points), cookie)
+	return PolyPointCookie(cookie)
+}
+
+func (c *Conn) PolyPointChecked(CoordinateMode byte, Drawable Id, Gc Id, Points []Point) PolyPointCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(polyPointRequest(CoordinateMode, Drawable, Gc, Points), cookie)
+	return PolyPointCookie(cookie)
+}
+
 // Write request to wire for PolyPoint
-func (c *Conn) PolyPoint(CoordinateMode byte, Drawable Id, Gc Id, Points []Point) {
-	size := (12 + pad((len(Points) * 4)))
+func polyPointRequest(CoordinateMode byte, Drawable Id, Gc Id, Points []Point) []byte {
+	size := pad((12 + pad((len(Points) * 4))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -8707,14 +9779,29 @@ func (c *Conn) PolyPoint(CoordinateMode byte, Drawable Id, Gc Id, Points []Point
 
 	b += PointListBytes(buf[b:], Points)
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request PolyLine
-// size: (12 + pad((len(Points) * 4)))
+// size: pad((12 + pad((len(Points) * 4))))
+type PolyLineCookie cookie
+
 // Write request to wire for PolyLine
-func (c *Conn) PolyLine(CoordinateMode byte, Drawable Id, Gc Id, Points []Point) {
-	size := (12 + pad((len(Points) * 4)))
+func (c *Conn) PolyLine(CoordinateMode byte, Drawable Id, Gc Id, Points []Point) PolyLineCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(polyLineRequest(CoordinateMode, Drawable, Gc, Points), cookie)
+	return PolyLineCookie(cookie)
+}
+
+func (c *Conn) PolyLineChecked(CoordinateMode byte, Drawable Id, Gc Id, Points []Point) PolyLineCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(polyLineRequest(CoordinateMode, Drawable, Gc, Points), cookie)
+	return PolyLineCookie(cookie)
+}
+
+// Write request to wire for PolyLine
+func polyLineRequest(CoordinateMode byte, Drawable Id, Gc Id, Points []Point) []byte {
+	size := pad((12 + pad((len(Points) * 4))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -8735,14 +9822,29 @@ func (c *Conn) PolyLine(CoordinateMode byte, Drawable Id, Gc Id, Points []Point)
 
 	b += PointListBytes(buf[b:], Points)
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request PolySegment
-// size: (12 + pad((len(Segments) * 8)))
+// size: pad((12 + pad((len(Segments) * 8))))
+type PolySegmentCookie cookie
+
 // Write request to wire for PolySegment
-func (c *Conn) PolySegment(Drawable Id, Gc Id, Segments []Segment) {
-	size := (12 + pad((len(Segments) * 8)))
+func (c *Conn) PolySegment(Drawable Id, Gc Id, Segments []Segment) PolySegmentCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(polySegmentRequest(Drawable, Gc, Segments), cookie)
+	return PolySegmentCookie(cookie)
+}
+
+func (c *Conn) PolySegmentChecked(Drawable Id, Gc Id, Segments []Segment) PolySegmentCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(polySegmentRequest(Drawable, Gc, Segments), cookie)
+	return PolySegmentCookie(cookie)
+}
+
+// Write request to wire for PolySegment
+func polySegmentRequest(Drawable Id, Gc Id, Segments []Segment) []byte {
+	size := pad((12 + pad((len(Segments) * 8))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -8762,14 +9864,29 @@ func (c *Conn) PolySegment(Drawable Id, Gc Id, Segments []Segment) {
 
 	b += SegmentListBytes(buf[b:], Segments)
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request PolyRectangle
-// size: (12 + pad((len(Rectangles) * 8)))
+// size: pad((12 + pad((len(Rectangles) * 8))))
+type PolyRectangleCookie cookie
+
 // Write request to wire for PolyRectangle
-func (c *Conn) PolyRectangle(Drawable Id, Gc Id, Rectangles []Rectangle) {
-	size := (12 + pad((len(Rectangles) * 8)))
+func (c *Conn) PolyRectangle(Drawable Id, Gc Id, Rectangles []Rectangle) PolyRectangleCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(polyRectangleRequest(Drawable, Gc, Rectangles), cookie)
+	return PolyRectangleCookie(cookie)
+}
+
+func (c *Conn) PolyRectangleChecked(Drawable Id, Gc Id, Rectangles []Rectangle) PolyRectangleCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(polyRectangleRequest(Drawable, Gc, Rectangles), cookie)
+	return PolyRectangleCookie(cookie)
+}
+
+// Write request to wire for PolyRectangle
+func polyRectangleRequest(Drawable Id, Gc Id, Rectangles []Rectangle) []byte {
+	size := pad((12 + pad((len(Rectangles) * 8))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -8789,14 +9906,29 @@ func (c *Conn) PolyRectangle(Drawable Id, Gc Id, Rectangles []Rectangle) {
 
 	b += RectangleListBytes(buf[b:], Rectangles)
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request PolyArc
-// size: (12 + pad((len(Arcs) * 12)))
+// size: pad((12 + pad((len(Arcs) * 12))))
+type PolyArcCookie cookie
+
 // Write request to wire for PolyArc
-func (c *Conn) PolyArc(Drawable Id, Gc Id, Arcs []Arc) {
-	size := (12 + pad((len(Arcs) * 12)))
+func (c *Conn) PolyArc(Drawable Id, Gc Id, Arcs []Arc) PolyArcCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(polyArcRequest(Drawable, Gc, Arcs), cookie)
+	return PolyArcCookie(cookie)
+}
+
+func (c *Conn) PolyArcChecked(Drawable Id, Gc Id, Arcs []Arc) PolyArcCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(polyArcRequest(Drawable, Gc, Arcs), cookie)
+	return PolyArcCookie(cookie)
+}
+
+// Write request to wire for PolyArc
+func polyArcRequest(Drawable Id, Gc Id, Arcs []Arc) []byte {
+	size := pad((12 + pad((len(Arcs) * 12))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -8816,14 +9948,29 @@ func (c *Conn) PolyArc(Drawable Id, Gc Id, Arcs []Arc) {
 
 	b += ArcListBytes(buf[b:], Arcs)
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request FillPoly
-// size: (16 + pad((len(Points) * 4)))
+// size: pad((16 + pad((len(Points) * 4))))
+type FillPolyCookie cookie
+
 // Write request to wire for FillPoly
-func (c *Conn) FillPoly(Drawable Id, Gc Id, Shape byte, CoordinateMode byte, Points []Point) {
-	size := (16 + pad((len(Points) * 4)))
+func (c *Conn) FillPoly(Drawable Id, Gc Id, Shape byte, CoordinateMode byte, Points []Point) FillPolyCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(fillPolyRequest(Drawable, Gc, Shape, CoordinateMode, Points), cookie)
+	return FillPolyCookie(cookie)
+}
+
+func (c *Conn) FillPolyChecked(Drawable Id, Gc Id, Shape byte, CoordinateMode byte, Points []Point) FillPolyCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(fillPolyRequest(Drawable, Gc, Shape, CoordinateMode, Points), cookie)
+	return FillPolyCookie(cookie)
+}
+
+// Write request to wire for FillPoly
+func fillPolyRequest(Drawable Id, Gc Id, Shape byte, CoordinateMode byte, Points []Point) []byte {
+	size := pad((16 + pad((len(Points) * 4))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -8851,14 +9998,29 @@ func (c *Conn) FillPoly(Drawable Id, Gc Id, Shape byte, CoordinateMode byte, Poi
 
 	b += PointListBytes(buf[b:], Points)
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request PolyFillRectangle
-// size: (12 + pad((len(Rectangles) * 8)))
+// size: pad((12 + pad((len(Rectangles) * 8))))
+type PolyFillRectangleCookie cookie
+
+// Write request to wire for PolyFillRectangle
+func (c *Conn) PolyFillRectangle(Drawable Id, Gc Id, Rectangles []Rectangle) PolyFillRectangleCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(polyFillRectangleRequest(Drawable, Gc, Rectangles), cookie)
+	return PolyFillRectangleCookie(cookie)
+}
+
+func (c *Conn) PolyFillRectangleChecked(Drawable Id, Gc Id, Rectangles []Rectangle) PolyFillRectangleCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(polyFillRectangleRequest(Drawable, Gc, Rectangles), cookie)
+	return PolyFillRectangleCookie(cookie)
+}
+
 // Write request to wire for PolyFillRectangle
-func (c *Conn) PolyFillRectangle(Drawable Id, Gc Id, Rectangles []Rectangle) {
-	size := (12 + pad((len(Rectangles) * 8)))
+func polyFillRectangleRequest(Drawable Id, Gc Id, Rectangles []Rectangle) []byte {
+	size := pad((12 + pad((len(Rectangles) * 8))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -8878,14 +10040,29 @@ func (c *Conn) PolyFillRectangle(Drawable Id, Gc Id, Rectangles []Rectangle) {
 
 	b += RectangleListBytes(buf[b:], Rectangles)
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request PolyFillArc
-// size: (12 + pad((len(Arcs) * 12)))
+// size: pad((12 + pad((len(Arcs) * 12))))
+type PolyFillArcCookie cookie
+
 // Write request to wire for PolyFillArc
-func (c *Conn) PolyFillArc(Drawable Id, Gc Id, Arcs []Arc) {
-	size := (12 + pad((len(Arcs) * 12)))
+func (c *Conn) PolyFillArc(Drawable Id, Gc Id, Arcs []Arc) PolyFillArcCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(polyFillArcRequest(Drawable, Gc, Arcs), cookie)
+	return PolyFillArcCookie(cookie)
+}
+
+func (c *Conn) PolyFillArcChecked(Drawable Id, Gc Id, Arcs []Arc) PolyFillArcCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(polyFillArcRequest(Drawable, Gc, Arcs), cookie)
+	return PolyFillArcCookie(cookie)
+}
+
+// Write request to wire for PolyFillArc
+func polyFillArcRequest(Drawable Id, Gc Id, Arcs []Arc) []byte {
+	size := pad((12 + pad((len(Arcs) * 12))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -8905,14 +10082,29 @@ func (c *Conn) PolyFillArc(Drawable Id, Gc Id, Arcs []Arc) {
 
 	b += ArcListBytes(buf[b:], Arcs)
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request PutImage
-// size: (24 + pad((len(Data) * 1)))
+// size: pad((24 + pad((len(Data) * 1))))
+type PutImageCookie cookie
+
 // Write request to wire for PutImage
-func (c *Conn) PutImage(Format byte, Drawable Id, Gc Id, Width uint16, Height uint16, DstX int16, DstY int16, LeftPad byte, Depth byte, Data []byte) {
-	size := (24 + pad((len(Data) * 1)))
+func (c *Conn) PutImage(Format byte, Drawable Id, Gc Id, Width uint16, Height uint16, DstX int16, DstY int16, LeftPad byte, Depth byte, Data []byte) PutImageCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(putImageRequest(Format, Drawable, Gc, Width, Height, DstX, DstY, LeftPad, Depth, Data), cookie)
+	return PutImageCookie(cookie)
+}
+
+func (c *Conn) PutImageChecked(Format byte, Drawable Id, Gc Id, Width uint16, Height uint16, DstX int16, DstY int16, LeftPad byte, Depth byte, Data []byte) PutImageCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(putImageRequest(Format, Drawable, Gc, Width, Height, DstX, DstY, LeftPad, Depth, Data), cookie)
+	return PutImageCookie(cookie)
+}
+
+// Write request to wire for PutImage
+func putImageRequest(Format byte, Drawable Id, Gc Id, Width uint16, Height uint16, DstX int16, DstY int16, LeftPad byte, Depth byte, Data []byte) []byte {
+	size := pad((24 + pad((len(Data) * 1))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -8954,49 +10146,23 @@ func (c *Conn) PutImage(Format byte, Drawable Id, Gc Id, Width uint16, Height ui
 	copy(buf[b:], Data[:len(Data)])
 	b += pad(int(len(Data)))
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request GetImage
 // size: 20
-func (c *Conn) GetImage(Format byte, Drawable Id, X int16, Y int16, Width uint16, Height uint16, PlaneMask uint32) (*GetImageReply, error) {
-	return c.GetImageReply(c.GetImageRequest(Format, Drawable, X, Y, Width, Height, PlaneMask))
-}
-
-// Write request to wire for GetImage
-func (c *Conn) GetImageRequest(Format byte, Drawable Id, X int16, Y int16, Width uint16, Height uint16, PlaneMask uint32) *Cookie {
-	size := 20
-	b := 0
-	buf := make([]byte, size)
+type GetImageCookie cookie
 
-	buf[b] = 73 // request opcode
-	b += 1
-
-	buf[b] = Format
-	b += 1
-
-	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
-	b += 2
-
-	Put32(buf[b:], uint32(Drawable))
-	b += 4
-
-	Put16(buf[b:], uint16(X))
-	b += 2
-
-	Put16(buf[b:], uint16(Y))
-	b += 2
-
-	Put16(buf[b:], Width)
-	b += 2
-
-	Put16(buf[b:], Height)
-	b += 2
-
-	Put32(buf[b:], PlaneMask)
-	b += 4
+func (c *Conn) GetImage(Format byte, Drawable Id, X int16, Y int16, Width uint16, Height uint16, PlaneMask uint32) GetImageCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(getImageRequest(Format, Drawable, X, Y, Width, Height, PlaneMask), cookie)
+	return GetImageCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) GetImageUnchecked(Format byte, Drawable Id, X int16, Y int16, Width uint16, Height uint16, PlaneMask uint32) GetImageCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(getImageRequest(Format, Drawable, X, Y, Width, Height, PlaneMask), cookie)
+	return GetImageCookie(cookie)
 }
 
 // Request reply for GetImage
@@ -9010,13 +10176,17 @@ type GetImageReply struct {
 	Data []byte // size: pad(((int(Length) * 4) * 1))
 }
 
-// Read reply GetImage
-func (c *Conn) GetImageReply(cook *Cookie) (*GetImageReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request GetImage
+func (cook GetImageCookie) Reply() (*GetImageReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return getImageReply(buf), nil
+}
 
+// Read reply into structure from buffer for GetImage
+func getImageReply(buf []byte) *GetImageReply {
 	v := new(GetImageReply)
 	b := 1 // skip reply determinant
 
@@ -9038,14 +10208,65 @@ func (c *Conn) GetImageReply(cook *Cookie) (*GetImageReply, error) {
 	copy(v.Data[:(int(v.Length)*4)], buf[b:])
 	b += pad(int((int(v.Length) * 4)))
 
-	return v, nil
+	return v
+}
+
+// Write request to wire for GetImage
+func getImageRequest(Format byte, Drawable Id, X int16, Y int16, Width uint16, Height uint16, PlaneMask uint32) []byte {
+	size := 20
+	b := 0
+	buf := make([]byte, size)
+
+	buf[b] = 73 // request opcode
+	b += 1
+
+	buf[b] = Format
+	b += 1
+
+	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
+	b += 2
+
+	Put32(buf[b:], uint32(Drawable))
+	b += 4
+
+	Put16(buf[b:], uint16(X))
+	b += 2
+
+	Put16(buf[b:], uint16(Y))
+	b += 2
+
+	Put16(buf[b:], Width)
+	b += 2
+
+	Put16(buf[b:], Height)
+	b += 2
+
+	Put32(buf[b:], PlaneMask)
+	b += 4
+
+	return buf
 }
 
 // Request PolyText8
-// size: (16 + pad((len(Items) * 1)))
+// size: pad((16 + pad((len(Items) * 1))))
+type PolyText8Cookie cookie
+
+// Write request to wire for PolyText8
+func (c *Conn) PolyText8(Drawable Id, Gc Id, X int16, Y int16, Items []byte) PolyText8Cookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(polyText8Request(Drawable, Gc, X, Y, Items), cookie)
+	return PolyText8Cookie(cookie)
+}
+
+func (c *Conn) PolyText8Checked(Drawable Id, Gc Id, X int16, Y int16, Items []byte) PolyText8Cookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(polyText8Request(Drawable, Gc, X, Y, Items), cookie)
+	return PolyText8Cookie(cookie)
+}
+
 // Write request to wire for PolyText8
-func (c *Conn) PolyText8(Drawable Id, Gc Id, X int16, Y int16, Items []byte) {
-	size := (16 + pad((len(Items) * 1)))
+func polyText8Request(Drawable Id, Gc Id, X int16, Y int16, Items []byte) []byte {
+	size := pad((16 + pad((len(Items) * 1))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -9072,14 +10293,29 @@ func (c *Conn) PolyText8(Drawable Id, Gc Id, X int16, Y int16, Items []byte) {
 	copy(buf[b:], Items[:len(Items)])
 	b += pad(int(len(Items)))
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request PolyText16
-// size: (16 + pad((len(Items) * 1)))
+// size: pad((16 + pad((len(Items) * 1))))
+type PolyText16Cookie cookie
+
 // Write request to wire for PolyText16
-func (c *Conn) PolyText16(Drawable Id, Gc Id, X int16, Y int16, Items []byte) {
-	size := (16 + pad((len(Items) * 1)))
+func (c *Conn) PolyText16(Drawable Id, Gc Id, X int16, Y int16, Items []byte) PolyText16Cookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(polyText16Request(Drawable, Gc, X, Y, Items), cookie)
+	return PolyText16Cookie(cookie)
+}
+
+func (c *Conn) PolyText16Checked(Drawable Id, Gc Id, X int16, Y int16, Items []byte) PolyText16Cookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(polyText16Request(Drawable, Gc, X, Y, Items), cookie)
+	return PolyText16Cookie(cookie)
+}
+
+// Write request to wire for PolyText16
+func polyText16Request(Drawable Id, Gc Id, X int16, Y int16, Items []byte) []byte {
+	size := pad((16 + pad((len(Items) * 1))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -9106,14 +10342,29 @@ func (c *Conn) PolyText16(Drawable Id, Gc Id, X int16, Y int16, Items []byte) {
 	copy(buf[b:], Items[:len(Items)])
 	b += pad(int(len(Items)))
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request ImageText8
-// size: (16 + pad((int(StringLen) * 1)))
+// size: pad((16 + pad((int(StringLen) * 1))))
+type ImageText8Cookie cookie
+
+// Write request to wire for ImageText8
+func (c *Conn) ImageText8(StringLen byte, Drawable Id, Gc Id, X int16, Y int16, String string) ImageText8Cookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(imageText8Request(StringLen, Drawable, Gc, X, Y, String), cookie)
+	return ImageText8Cookie(cookie)
+}
+
+func (c *Conn) ImageText8Checked(StringLen byte, Drawable Id, Gc Id, X int16, Y int16, String string) ImageText8Cookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(imageText8Request(StringLen, Drawable, Gc, X, Y, String), cookie)
+	return ImageText8Cookie(cookie)
+}
+
 // Write request to wire for ImageText8
-func (c *Conn) ImageText8(StringLen byte, Drawable Id, Gc Id, X int16, Y int16, String string) {
-	size := (16 + pad((int(StringLen) * 1)))
+func imageText8Request(StringLen byte, Drawable Id, Gc Id, X int16, Y int16, String string) []byte {
+	size := pad((16 + pad((int(StringLen) * 1))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -9141,14 +10392,29 @@ func (c *Conn) ImageText8(StringLen byte, Drawable Id, Gc Id, X int16, Y int16,
 	copy(buf[b:], String[:StringLen])
 	b += pad(int(StringLen))
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request ImageText16
-// size: (16 + pad((int(StringLen) * 2)))
+// size: pad((16 + pad((int(StringLen) * 2))))
+type ImageText16Cookie cookie
+
+// Write request to wire for ImageText16
+func (c *Conn) ImageText16(StringLen byte, Drawable Id, Gc Id, X int16, Y int16, String []Char2b) ImageText16Cookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(imageText16Request(StringLen, Drawable, Gc, X, Y, String), cookie)
+	return ImageText16Cookie(cookie)
+}
+
+func (c *Conn) ImageText16Checked(StringLen byte, Drawable Id, Gc Id, X int16, Y int16, String []Char2b) ImageText16Cookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(imageText16Request(StringLen, Drawable, Gc, X, Y, String), cookie)
+	return ImageText16Cookie(cookie)
+}
+
 // Write request to wire for ImageText16
-func (c *Conn) ImageText16(StringLen byte, Drawable Id, Gc Id, X int16, Y int16, String []Char2b) {
-	size := (16 + pad((int(StringLen) * 2)))
+func imageText16Request(StringLen byte, Drawable Id, Gc Id, X int16, Y int16, String []Char2b) []byte {
+	size := pad((16 + pad((int(StringLen) * 2))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -9175,13 +10441,28 @@ func (c *Conn) ImageText16(StringLen byte, Drawable Id, Gc Id, X int16, Y int16,
 
 	b += Char2bListBytes(buf[b:], String)
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request CreateColormap
 // size: 16
+type CreateColormapCookie cookie
+
+// Write request to wire for CreateColormap
+func (c *Conn) CreateColormap(Alloc byte, Mid Id, Window Id, Visual Visualid) CreateColormapCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(createColormapRequest(Alloc, Mid, Window, Visual), cookie)
+	return CreateColormapCookie(cookie)
+}
+
+func (c *Conn) CreateColormapChecked(Alloc byte, Mid Id, Window Id, Visual Visualid) CreateColormapCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(createColormapRequest(Alloc, Mid, Window, Visual), cookie)
+	return CreateColormapCookie(cookie)
+}
+
 // Write request to wire for CreateColormap
-func (c *Conn) CreateColormap(Alloc byte, Mid Id, Window Id, Visual Visualid) {
+func createColormapRequest(Alloc byte, Mid Id, Window Id, Visual Visualid) []byte {
 	size := 16
 	b := 0
 	buf := make([]byte, size)
@@ -9204,13 +10485,28 @@ func (c *Conn) CreateColormap(Alloc byte, Mid Id, Window Id, Visual Visualid) {
 	Put32(buf[b:], uint32(Visual))
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request FreeColormap
 // size: 8
+type FreeColormapCookie cookie
+
+// Write request to wire for FreeColormap
+func (c *Conn) FreeColormap(Cmap Id) FreeColormapCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(freeColormapRequest(Cmap), cookie)
+	return FreeColormapCookie(cookie)
+}
+
+func (c *Conn) FreeColormapChecked(Cmap Id) FreeColormapCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(freeColormapRequest(Cmap), cookie)
+	return FreeColormapCookie(cookie)
+}
+
 // Write request to wire for FreeColormap
-func (c *Conn) FreeColormap(Cmap Id) {
+func freeColormapRequest(Cmap Id) []byte {
 	size := 8
 	b := 0
 	buf := make([]byte, size)
@@ -9226,13 +10522,28 @@ func (c *Conn) FreeColormap(Cmap Id) {
 	Put32(buf[b:], uint32(Cmap))
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request CopyColormapAndFree
 // size: 12
+type CopyColormapAndFreeCookie cookie
+
 // Write request to wire for CopyColormapAndFree
-func (c *Conn) CopyColormapAndFree(Mid Id, SrcCmap Id) {
+func (c *Conn) CopyColormapAndFree(Mid Id, SrcCmap Id) CopyColormapAndFreeCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(copyColormapAndFreeRequest(Mid, SrcCmap), cookie)
+	return CopyColormapAndFreeCookie(cookie)
+}
+
+func (c *Conn) CopyColormapAndFreeChecked(Mid Id, SrcCmap Id) CopyColormapAndFreeCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(copyColormapAndFreeRequest(Mid, SrcCmap), cookie)
+	return CopyColormapAndFreeCookie(cookie)
+}
+
+// Write request to wire for CopyColormapAndFree
+func copyColormapAndFreeRequest(Mid Id, SrcCmap Id) []byte {
 	size := 12
 	b := 0
 	buf := make([]byte, size)
@@ -9251,13 +10562,28 @@ func (c *Conn) CopyColormapAndFree(Mid Id, SrcCmap Id) {
 	Put32(buf[b:], uint32(SrcCmap))
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request InstallColormap
 // size: 8
+type InstallColormapCookie cookie
+
+// Write request to wire for InstallColormap
+func (c *Conn) InstallColormap(Cmap Id) InstallColormapCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(installColormapRequest(Cmap), cookie)
+	return InstallColormapCookie(cookie)
+}
+
+func (c *Conn) InstallColormapChecked(Cmap Id) InstallColormapCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(installColormapRequest(Cmap), cookie)
+	return InstallColormapCookie(cookie)
+}
+
 // Write request to wire for InstallColormap
-func (c *Conn) InstallColormap(Cmap Id) {
+func installColormapRequest(Cmap Id) []byte {
 	size := 8
 	b := 0
 	buf := make([]byte, size)
@@ -9273,13 +10599,28 @@ func (c *Conn) InstallColormap(Cmap Id) {
 	Put32(buf[b:], uint32(Cmap))
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request UninstallColormap
 // size: 8
+type UninstallColormapCookie cookie
+
 // Write request to wire for UninstallColormap
-func (c *Conn) UninstallColormap(Cmap Id) {
+func (c *Conn) UninstallColormap(Cmap Id) UninstallColormapCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(uninstallColormapRequest(Cmap), cookie)
+	return UninstallColormapCookie(cookie)
+}
+
+func (c *Conn) UninstallColormapChecked(Cmap Id) UninstallColormapCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(uninstallColormapRequest(Cmap), cookie)
+	return UninstallColormapCookie(cookie)
+}
+
+// Write request to wire for UninstallColormap
+func uninstallColormapRequest(Cmap Id) []byte {
 	size := 8
 	b := 0
 	buf := make([]byte, size)
@@ -9295,33 +10636,23 @@ func (c *Conn) UninstallColormap(Cmap Id) {
 	Put32(buf[b:], uint32(Cmap))
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request ListInstalledColormaps
 // size: 8
-func (c *Conn) ListInstalledColormaps(Window Id) (*ListInstalledColormapsReply, error) {
-	return c.ListInstalledColormapsReply(c.ListInstalledColormapsRequest(Window))
-}
+type ListInstalledColormapsCookie cookie
 
-// Write request to wire for ListInstalledColormaps
-func (c *Conn) ListInstalledColormapsRequest(Window Id) *Cookie {
-	size := 8
-	b := 0
-	buf := make([]byte, size)
-
-	buf[b] = 83 // request opcode
-	b += 1
-
-	b += 1 // padding
-
-	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
-	b += 2
-
-	Put32(buf[b:], uint32(Window))
-	b += 4
+func (c *Conn) ListInstalledColormaps(Window Id) ListInstalledColormapsCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(listInstalledColormapsRequest(Window), cookie)
+	return ListInstalledColormapsCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) ListInstalledColormapsUnchecked(Window Id) ListInstalledColormapsCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(listInstalledColormapsRequest(Window), cookie)
+	return ListInstalledColormapsCookie(cookie)
 }
 
 // Request reply for ListInstalledColormaps
@@ -9335,13 +10666,17 @@ type ListInstalledColormapsReply struct {
 	Cmaps []Id // size: pad((int(CmapsLen) * 4))
 }
 
-// Read reply ListInstalledColormaps
-func (c *Conn) ListInstalledColormapsReply(cook *Cookie) (*ListInstalledColormapsReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request ListInstalledColormaps
+func (cook ListInstalledColormapsCookie) Reply() (*ListInstalledColormapsReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return listInstalledColormapsReply(buf), nil
+}
 
+// Read reply into structure from buffer for ListInstalledColormaps
+func listInstalledColormapsReply(buf []byte) *ListInstalledColormapsReply {
 	v := new(ListInstalledColormapsReply)
 	b := 1 // skip reply determinant
 
@@ -9365,22 +10700,16 @@ func (c *Conn) ListInstalledColormapsReply(cook *Cookie) (*ListInstalledColormap
 	}
 	b = pad(b)
 
-	return v, nil
-}
-
-// Request AllocColor
-// size: 16
-func (c *Conn) AllocColor(Cmap Id, Red uint16, Green uint16, Blue uint16) (*AllocColorReply, error) {
-	return c.AllocColorReply(c.AllocColorRequest(Cmap, Red, Green, Blue))
+	return v
 }
 
-// Write request to wire for AllocColor
-func (c *Conn) AllocColorRequest(Cmap Id, Red uint16, Green uint16, Blue uint16) *Cookie {
-	size := 16
+// Write request to wire for ListInstalledColormaps
+func listInstalledColormapsRequest(Window Id) []byte {
+	size := 8
 	b := 0
 	buf := make([]byte, size)
 
-	buf[b] = 84 // request opcode
+	buf[b] = 83 // request opcode
 	b += 1
 
 	b += 1 // padding
@@ -9388,21 +10717,26 @@ func (c *Conn) AllocColorRequest(Cmap Id, Red uint16, Green uint16, Blue uint16)
 	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
 	b += 2
 
-	Put32(buf[b:], uint32(Cmap))
+	Put32(buf[b:], uint32(Window))
 	b += 4
 
-	Put16(buf[b:], Red)
-	b += 2
-
-	Put16(buf[b:], Green)
-	b += 2
+	return buf
+}
 
-	Put16(buf[b:], Blue)
-	b += 2
+// Request AllocColor
+// size: 16
+type AllocColorCookie cookie
 
-	b += 2 // padding
+func (c *Conn) AllocColor(Cmap Id, Red uint16, Green uint16, Blue uint16) AllocColorCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(allocColorRequest(Cmap, Red, Green, Blue), cookie)
+	return AllocColorCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) AllocColorUnchecked(Cmap Id, Red uint16, Green uint16, Blue uint16) AllocColorCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(allocColorRequest(Cmap, Red, Green, Blue), cookie)
+	return AllocColorCookie(cookie)
 }
 
 // Request reply for AllocColor
@@ -9418,13 +10752,17 @@ type AllocColorReply struct {
 	Pixel uint32
 }
 
-// Read reply AllocColor
-func (c *Conn) AllocColorReply(cook *Cookie) (*AllocColorReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request AllocColor
+func (cook AllocColorCookie) Reply() (*AllocColorReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return allocColorReply(buf), nil
+}
 
+// Read reply into structure from buffer for AllocColor
+func allocColorReply(buf []byte) *AllocColorReply {
 	v := new(AllocColorReply)
 	b := 1 // skip reply determinant
 
@@ -9450,22 +10788,16 @@ func (c *Conn) AllocColorReply(cook *Cookie) (*AllocColorReply, error) {
 	v.Pixel = Get32(buf[b:])
 	b += 4
 
-	return v, nil
-}
-
-// Request AllocNamedColor
-// size: (12 + pad((int(NameLen) * 1)))
-func (c *Conn) AllocNamedColor(Cmap Id, NameLen uint16, Name string) (*AllocNamedColorReply, error) {
-	return c.AllocNamedColorReply(c.AllocNamedColorRequest(Cmap, NameLen, Name))
+	return v
 }
 
-// Write request to wire for AllocNamedColor
-func (c *Conn) AllocNamedColorRequest(Cmap Id, NameLen uint16, Name string) *Cookie {
-	size := (12 + pad((int(NameLen) * 1)))
+// Write request to wire for AllocColor
+func allocColorRequest(Cmap Id, Red uint16, Green uint16, Blue uint16) []byte {
+	size := 16
 	b := 0
 	buf := make([]byte, size)
 
-	buf[b] = 85 // request opcode
+	buf[b] = 84 // request opcode
 	b += 1
 
 	b += 1 // padding
@@ -9476,15 +10808,34 @@ func (c *Conn) AllocNamedColorRequest(Cmap Id, NameLen uint16, Name string) *Coo
 	Put32(buf[b:], uint32(Cmap))
 	b += 4
 
-	Put16(buf[b:], NameLen)
+	Put16(buf[b:], Red)
+	b += 2
+
+	Put16(buf[b:], Green)
+	b += 2
+
+	Put16(buf[b:], Blue)
 	b += 2
 
 	b += 2 // padding
 
-	copy(buf[b:], Name[:NameLen])
-	b += pad(int(NameLen))
+	return buf
+}
+
+// Request AllocNamedColor
+// size: pad((12 + pad((int(NameLen) * 1))))
+type AllocNamedColorCookie cookie
+
+func (c *Conn) AllocNamedColor(Cmap Id, NameLen uint16, Name string) AllocNamedColorCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(allocNamedColorRequest(Cmap, NameLen, Name), cookie)
+	return AllocNamedColorCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) AllocNamedColorUnchecked(Cmap Id, NameLen uint16, Name string) AllocNamedColorCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(allocNamedColorRequest(Cmap, NameLen, Name), cookie)
+	return AllocNamedColorCookie(cookie)
 }
 
 // Request reply for AllocNamedColor
@@ -9502,13 +10853,17 @@ type AllocNamedColorReply struct {
 	VisualBlue  uint16
 }
 
-// Read reply AllocNamedColor
-func (c *Conn) AllocNamedColorReply(cook *Cookie) (*AllocNamedColorReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request AllocNamedColor
+func (cook AllocNamedColorCookie) Reply() (*AllocNamedColorReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return allocNamedColorReply(buf), nil
+}
 
+// Read reply into structure from buffer for AllocNamedColor
+func allocNamedColorReply(buf []byte) *AllocNamedColorReply {
 	v := new(AllocNamedColorReply)
 	b := 1 // skip reply determinant
 
@@ -9541,30 +10896,19 @@ func (c *Conn) AllocNamedColorReply(cook *Cookie) (*AllocNamedColorReply, error)
 	v.VisualBlue = Get16(buf[b:])
 	b += 2
 
-	return v, nil
-}
-
-// Request AllocColorCells
-// size: 12
-func (c *Conn) AllocColorCells(Contiguous bool, Cmap Id, Colors uint16, Planes uint16) (*AllocColorCellsReply, error) {
-	return c.AllocColorCellsReply(c.AllocColorCellsRequest(Contiguous, Cmap, Colors, Planes))
+	return v
 }
 
-// Write request to wire for AllocColorCells
-func (c *Conn) AllocColorCellsRequest(Contiguous bool, Cmap Id, Colors uint16, Planes uint16) *Cookie {
-	size := 12
+// Write request to wire for AllocNamedColor
+func allocNamedColorRequest(Cmap Id, NameLen uint16, Name string) []byte {
+	size := pad((12 + pad((int(NameLen) * 1))))
 	b := 0
 	buf := make([]byte, size)
 
-	buf[b] = 86 // request opcode
+	buf[b] = 85 // request opcode
 	b += 1
 
-	if Contiguous {
-		buf[b] = 1
-	} else {
-		buf[b] = 0
-	}
-	b += 1
+	b += 1 // padding
 
 	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
 	b += 2
@@ -9572,13 +10916,31 @@ func (c *Conn) AllocColorCellsRequest(Contiguous bool, Cmap Id, Colors uint16, P
 	Put32(buf[b:], uint32(Cmap))
 	b += 4
 
-	Put16(buf[b:], Colors)
+	Put16(buf[b:], NameLen)
 	b += 2
 
-	Put16(buf[b:], Planes)
-	b += 2
+	b += 2 // padding
+
+	copy(buf[b:], Name[:NameLen])
+	b += pad(int(NameLen))
 
-	return c.sendRequest(true, buf)
+	return buf
+}
+
+// Request AllocColorCells
+// size: 12
+type AllocColorCellsCookie cookie
+
+func (c *Conn) AllocColorCells(Contiguous bool, Cmap Id, Colors uint16, Planes uint16) AllocColorCellsCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(allocColorCellsRequest(Contiguous, Cmap, Colors, Planes), cookie)
+	return AllocColorCellsCookie(cookie)
+}
+
+func (c *Conn) AllocColorCellsUnchecked(Contiguous bool, Cmap Id, Colors uint16, Planes uint16) AllocColorCellsCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(allocColorCellsRequest(Contiguous, Cmap, Colors, Planes), cookie)
+	return AllocColorCellsCookie(cookie)
 }
 
 // Request reply for AllocColorCells
@@ -9594,13 +10956,17 @@ type AllocColorCellsReply struct {
 	Masks  []uint32 // size: pad((int(MasksLen) * 4))
 }
 
-// Read reply AllocColorCells
-func (c *Conn) AllocColorCellsReply(cook *Cookie) (*AllocColorCellsReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request AllocColorCells
+func (cook AllocColorCellsCookie) Reply() (*AllocColorCellsReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return allocColorCellsReply(buf), nil
+}
 
+// Read reply into structure from buffer for AllocColorCells
+func allocColorCellsReply(buf []byte) *AllocColorCellsReply {
 	v := new(AllocColorCellsReply)
 	b := 1 // skip reply determinant
 
@@ -9634,22 +11000,16 @@ func (c *Conn) AllocColorCellsReply(cook *Cookie) (*AllocColorCellsReply, error)
 	}
 	b = pad(b)
 
-	return v, nil
-}
-
-// Request AllocColorPlanes
-// size: 16
-func (c *Conn) AllocColorPlanes(Contiguous bool, Cmap Id, Colors uint16, Reds uint16, Greens uint16, Blues uint16) (*AllocColorPlanesReply, error) {
-	return c.AllocColorPlanesReply(c.AllocColorPlanesRequest(Contiguous, Cmap, Colors, Reds, Greens, Blues))
+	return v
 }
 
-// Write request to wire for AllocColorPlanes
-func (c *Conn) AllocColorPlanesRequest(Contiguous bool, Cmap Id, Colors uint16, Reds uint16, Greens uint16, Blues uint16) *Cookie {
-	size := 16
+// Write request to wire for AllocColorCells
+func allocColorCellsRequest(Contiguous bool, Cmap Id, Colors uint16, Planes uint16) []byte {
+	size := 12
 	b := 0
 	buf := make([]byte, size)
 
-	buf[b] = 87 // request opcode
+	buf[b] = 86 // request opcode
 	b += 1
 
 	if Contiguous {
@@ -9668,16 +11028,26 @@ func (c *Conn) AllocColorPlanesRequest(Contiguous bool, Cmap Id, Colors uint16,
 	Put16(buf[b:], Colors)
 	b += 2
 
-	Put16(buf[b:], Reds)
+	Put16(buf[b:], Planes)
 	b += 2
 
-	Put16(buf[b:], Greens)
-	b += 2
+	return buf
+}
 
-	Put16(buf[b:], Blues)
-	b += 2
+// Request AllocColorPlanes
+// size: 16
+type AllocColorPlanesCookie cookie
+
+func (c *Conn) AllocColorPlanes(Contiguous bool, Cmap Id, Colors uint16, Reds uint16, Greens uint16, Blues uint16) AllocColorPlanesCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(allocColorPlanesRequest(Contiguous, Cmap, Colors, Reds, Greens, Blues), cookie)
+	return AllocColorPlanesCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) AllocColorPlanesUnchecked(Contiguous bool, Cmap Id, Colors uint16, Reds uint16, Greens uint16, Blues uint16) AllocColorPlanesCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(allocColorPlanesRequest(Contiguous, Cmap, Colors, Reds, Greens, Blues), cookie)
+	return AllocColorPlanesCookie(cookie)
 }
 
 // Request reply for AllocColorPlanes
@@ -9695,13 +11065,17 @@ type AllocColorPlanesReply struct {
 	Pixels []uint32 // size: pad((int(PixelsLen) * 4))
 }
 
-// Read reply AllocColorPlanes
-func (c *Conn) AllocColorPlanesReply(cook *Cookie) (*AllocColorPlanesReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request AllocColorPlanes
+func (cook AllocColorPlanesCookie) Reply() (*AllocColorPlanesReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return allocColorPlanesReply(buf), nil
+}
 
+// Read reply into structure from buffer for AllocColorPlanes
+func allocColorPlanesReply(buf []byte) *AllocColorPlanesReply {
 	v := new(AllocColorPlanesReply)
 	b := 1 // skip reply determinant
 
@@ -9736,14 +11110,66 @@ func (c *Conn) AllocColorPlanesReply(cook *Cookie) (*AllocColorPlanesReply, erro
 	}
 	b = pad(b)
 
-	return v, nil
+	return v
+}
+
+// Write request to wire for AllocColorPlanes
+func allocColorPlanesRequest(Contiguous bool, Cmap Id, Colors uint16, Reds uint16, Greens uint16, Blues uint16) []byte {
+	size := 16
+	b := 0
+	buf := make([]byte, size)
+
+	buf[b] = 87 // request opcode
+	b += 1
+
+	if Contiguous {
+		buf[b] = 1
+	} else {
+		buf[b] = 0
+	}
+	b += 1
+
+	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
+	b += 2
+
+	Put32(buf[b:], uint32(Cmap))
+	b += 4
+
+	Put16(buf[b:], Colors)
+	b += 2
+
+	Put16(buf[b:], Reds)
+	b += 2
+
+	Put16(buf[b:], Greens)
+	b += 2
+
+	Put16(buf[b:], Blues)
+	b += 2
+
+	return buf
 }
 
 // Request FreeColors
-// size: (12 + pad((len(Pixels) * 4)))
+// size: pad((12 + pad((len(Pixels) * 4))))
+type FreeColorsCookie cookie
+
 // Write request to wire for FreeColors
-func (c *Conn) FreeColors(Cmap Id, PlaneMask uint32, Pixels []uint32) {
-	size := (12 + pad((len(Pixels) * 4)))
+func (c *Conn) FreeColors(Cmap Id, PlaneMask uint32, Pixels []uint32) FreeColorsCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(freeColorsRequest(Cmap, PlaneMask, Pixels), cookie)
+	return FreeColorsCookie(cookie)
+}
+
+func (c *Conn) FreeColorsChecked(Cmap Id, PlaneMask uint32, Pixels []uint32) FreeColorsCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(freeColorsRequest(Cmap, PlaneMask, Pixels), cookie)
+	return FreeColorsCookie(cookie)
+}
+
+// Write request to wire for FreeColors
+func freeColorsRequest(Cmap Id, PlaneMask uint32, Pixels []uint32) []byte {
+	size := pad((12 + pad((len(Pixels) * 4))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -9767,14 +11193,29 @@ func (c *Conn) FreeColors(Cmap Id, PlaneMask uint32, Pixels []uint32) {
 	}
 	b = pad(b)
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request StoreColors
-// size: (8 + pad((len(Items) * 12)))
+// size: pad((8 + pad((len(Items) * 12))))
+type StoreColorsCookie cookie
+
 // Write request to wire for StoreColors
-func (c *Conn) StoreColors(Cmap Id, Items []Coloritem) {
-	size := (8 + pad((len(Items) * 12)))
+func (c *Conn) StoreColors(Cmap Id, Items []Coloritem) StoreColorsCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(storeColorsRequest(Cmap, Items), cookie)
+	return StoreColorsCookie(cookie)
+}
+
+func (c *Conn) StoreColorsChecked(Cmap Id, Items []Coloritem) StoreColorsCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(storeColorsRequest(Cmap, Items), cookie)
+	return StoreColorsCookie(cookie)
+}
+
+// Write request to wire for StoreColors
+func storeColorsRequest(Cmap Id, Items []Coloritem) []byte {
+	size := pad((8 + pad((len(Items) * 12))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -9791,14 +11232,29 @@ func (c *Conn) StoreColors(Cmap Id, Items []Coloritem) {
 
 	b += ColoritemListBytes(buf[b:], Items)
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request StoreNamedColor
-// size: (16 + pad((int(NameLen) * 1)))
+// size: pad((16 + pad((int(NameLen) * 1))))
+type StoreNamedColorCookie cookie
+
+// Write request to wire for StoreNamedColor
+func (c *Conn) StoreNamedColor(Flags byte, Cmap Id, Pixel uint32, NameLen uint16, Name string) StoreNamedColorCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(storeNamedColorRequest(Flags, Cmap, Pixel, NameLen, Name), cookie)
+	return StoreNamedColorCookie(cookie)
+}
+
+func (c *Conn) StoreNamedColorChecked(Flags byte, Cmap Id, Pixel uint32, NameLen uint16, Name string) StoreNamedColorCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(storeNamedColorRequest(Flags, Cmap, Pixel, NameLen, Name), cookie)
+	return StoreNamedColorCookie(cookie)
+}
+
 // Write request to wire for StoreNamedColor
-func (c *Conn) StoreNamedColor(Flags byte, Cmap Id, Pixel uint32, NameLen uint16, Name string) {
-	size := (16 + pad((int(NameLen) * 1)))
+func storeNamedColorRequest(Flags byte, Cmap Id, Pixel uint32, NameLen uint16, Name string) []byte {
+	size := pad((16 + pad((int(NameLen) * 1))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -9825,39 +11281,23 @@ func (c *Conn) StoreNamedColor(Flags byte, Cmap Id, Pixel uint32, NameLen uint16
 	copy(buf[b:], Name[:NameLen])
 	b += pad(int(NameLen))
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request QueryColors
-// size: (8 + pad((len(Pixels) * 4)))
-func (c *Conn) QueryColors(Cmap Id, Pixels []uint32) (*QueryColorsReply, error) {
-	return c.QueryColorsReply(c.QueryColorsRequest(Cmap, Pixels))
-}
-
-// Write request to wire for QueryColors
-func (c *Conn) QueryColorsRequest(Cmap Id, Pixels []uint32) *Cookie {
-	size := (8 + pad((len(Pixels) * 4)))
-	b := 0
-	buf := make([]byte, size)
-
-	buf[b] = 91 // request opcode
-	b += 1
-
-	b += 1 // padding
-
-	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
-	b += 2
-
-	Put32(buf[b:], uint32(Cmap))
-	b += 4
+// size: pad((8 + pad((len(Pixels) * 4))))
+type QueryColorsCookie cookie
 
-	for i := 0; i < int(len(Pixels)); i++ {
-		Put32(buf[b:], Pixels[i])
-		b += 4
-	}
-	b = pad(b)
+func (c *Conn) QueryColors(Cmap Id, Pixels []uint32) QueryColorsCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(queryColorsRequest(Cmap, Pixels), cookie)
+	return QueryColorsCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) QueryColorsUnchecked(Cmap Id, Pixels []uint32) QueryColorsCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(queryColorsRequest(Cmap, Pixels), cookie)
+	return QueryColorsCookie(cookie)
 }
 
 // Request reply for QueryColors
@@ -9871,13 +11311,17 @@ type QueryColorsReply struct {
 	Colors []Rgb // size: pad((int(ColorsLen) * 8))
 }
 
-// Read reply QueryColors
-func (c *Conn) QueryColorsReply(cook *Cookie) (*QueryColorsReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request QueryColors
+func (cook QueryColorsCookie) Reply() (*QueryColorsReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return queryColorsReply(buf), nil
+}
 
+// Read reply into structure from buffer for QueryColors
+func queryColorsReply(buf []byte) *QueryColorsReply {
 	v := new(QueryColorsReply)
 	b := 1 // skip reply determinant
 
@@ -9897,22 +11341,16 @@ func (c *Conn) QueryColorsReply(cook *Cookie) (*QueryColorsReply, error) {
 	v.Colors = make([]Rgb, v.ColorsLen)
 	b += ReadRgbList(buf[b:], v.Colors)
 
-	return v, nil
-}
-
-// Request LookupColor
-// size: (12 + pad((int(NameLen) * 1)))
-func (c *Conn) LookupColor(Cmap Id, NameLen uint16, Name string) (*LookupColorReply, error) {
-	return c.LookupColorReply(c.LookupColorRequest(Cmap, NameLen, Name))
+	return v
 }
 
-// Write request to wire for LookupColor
-func (c *Conn) LookupColorRequest(Cmap Id, NameLen uint16, Name string) *Cookie {
-	size := (12 + pad((int(NameLen) * 1)))
+// Write request to wire for QueryColors
+func queryColorsRequest(Cmap Id, Pixels []uint32) []byte {
+	size := pad((8 + pad((len(Pixels) * 4))))
 	b := 0
 	buf := make([]byte, size)
 
-	buf[b] = 92 // request opcode
+	buf[b] = 91 // request opcode
 	b += 1
 
 	b += 1 // padding
@@ -9923,15 +11361,29 @@ func (c *Conn) LookupColorRequest(Cmap Id, NameLen uint16, Name string) *Cookie
 	Put32(buf[b:], uint32(Cmap))
 	b += 4
 
-	Put16(buf[b:], NameLen)
-	b += 2
+	for i := 0; i < int(len(Pixels)); i++ {
+		Put32(buf[b:], Pixels[i])
+		b += 4
+	}
+	b = pad(b)
 
-	b += 2 // padding
+	return buf
+}
 
-	copy(buf[b:], Name[:NameLen])
-	b += pad(int(NameLen))
+// Request LookupColor
+// size: pad((12 + pad((int(NameLen) * 1))))
+type LookupColorCookie cookie
+
+func (c *Conn) LookupColor(Cmap Id, NameLen uint16, Name string) LookupColorCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(lookupColorRequest(Cmap, NameLen, Name), cookie)
+	return LookupColorCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) LookupColorUnchecked(Cmap Id, NameLen uint16, Name string) LookupColorCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(lookupColorRequest(Cmap, NameLen, Name), cookie)
+	return LookupColorCookie(cookie)
 }
 
 // Request reply for LookupColor
@@ -9948,13 +11400,17 @@ type LookupColorReply struct {
 	VisualBlue  uint16
 }
 
-// Read reply LookupColor
-func (c *Conn) LookupColorReply(cook *Cookie) (*LookupColorReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request LookupColor
+func (cook LookupColorCookie) Reply() (*LookupColorReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return lookupColorReply(buf), nil
+}
 
+// Read reply into structure from buffer for LookupColor
+func lookupColorReply(buf []byte) *LookupColorReply {
 	v := new(LookupColorReply)
 	b := 1 // skip reply determinant
 
@@ -9984,13 +11440,56 @@ func (c *Conn) LookupColorReply(cook *Cookie) (*LookupColorReply, error) {
 	v.VisualBlue = Get16(buf[b:])
 	b += 2
 
-	return v, nil
+	return v
+}
+
+// Write request to wire for LookupColor
+func lookupColorRequest(Cmap Id, NameLen uint16, Name string) []byte {
+	size := pad((12 + pad((int(NameLen) * 1))))
+	b := 0
+	buf := make([]byte, size)
+
+	buf[b] = 92 // request opcode
+	b += 1
+
+	b += 1 // padding
+
+	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
+	b += 2
+
+	Put32(buf[b:], uint32(Cmap))
+	b += 4
+
+	Put16(buf[b:], NameLen)
+	b += 2
+
+	b += 2 // padding
+
+	copy(buf[b:], Name[:NameLen])
+	b += pad(int(NameLen))
+
+	return buf
 }
 
 // Request CreateCursor
 // size: 32
+type CreateCursorCookie cookie
+
+// Write request to wire for CreateCursor
+func (c *Conn) CreateCursor(Cid Id, Source Id, Mask Id, ForeRed uint16, ForeGreen uint16, ForeBlue uint16, BackRed uint16, BackGreen uint16, BackBlue uint16, X uint16, Y uint16) CreateCursorCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(createCursorRequest(Cid, Source, Mask, ForeRed, ForeGreen, ForeBlue, BackRed, BackGreen, BackBlue, X, Y), cookie)
+	return CreateCursorCookie(cookie)
+}
+
+func (c *Conn) CreateCursorChecked(Cid Id, Source Id, Mask Id, ForeRed uint16, ForeGreen uint16, ForeBlue uint16, BackRed uint16, BackGreen uint16, BackBlue uint16, X uint16, Y uint16) CreateCursorCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(createCursorRequest(Cid, Source, Mask, ForeRed, ForeGreen, ForeBlue, BackRed, BackGreen, BackBlue, X, Y), cookie)
+	return CreateCursorCookie(cookie)
+}
+
 // Write request to wire for CreateCursor
-func (c *Conn) CreateCursor(Cid Id, Source Id, Mask Id, ForeRed uint16, ForeGreen uint16, ForeBlue uint16, BackRed uint16, BackGreen uint16, BackBlue uint16, X uint16, Y uint16) {
+func createCursorRequest(Cid Id, Source Id, Mask Id, ForeRed uint16, ForeGreen uint16, ForeBlue uint16, BackRed uint16, BackGreen uint16, BackBlue uint16, X uint16, Y uint16) []byte {
 	size := 32
 	b := 0
 	buf := make([]byte, size)
@@ -10036,13 +11535,28 @@ func (c *Conn) CreateCursor(Cid Id, Source Id, Mask Id, ForeRed uint16, ForeGree
 	Put16(buf[b:], Y)
 	b += 2
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request CreateGlyphCursor
 // size: 32
+type CreateGlyphCursorCookie cookie
+
+// Write request to wire for CreateGlyphCursor
+func (c *Conn) CreateGlyphCursor(Cid Id, SourceFont Id, MaskFont Id, SourceChar uint16, MaskChar uint16, ForeRed uint16, ForeGreen uint16, ForeBlue uint16, BackRed uint16, BackGreen uint16, BackBlue uint16) CreateGlyphCursorCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(createGlyphCursorRequest(Cid, SourceFont, MaskFont, SourceChar, MaskChar, ForeRed, ForeGreen, ForeBlue, BackRed, BackGreen, BackBlue), cookie)
+	return CreateGlyphCursorCookie(cookie)
+}
+
+func (c *Conn) CreateGlyphCursorChecked(Cid Id, SourceFont Id, MaskFont Id, SourceChar uint16, MaskChar uint16, ForeRed uint16, ForeGreen uint16, ForeBlue uint16, BackRed uint16, BackGreen uint16, BackBlue uint16) CreateGlyphCursorCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(createGlyphCursorRequest(Cid, SourceFont, MaskFont, SourceChar, MaskChar, ForeRed, ForeGreen, ForeBlue, BackRed, BackGreen, BackBlue), cookie)
+	return CreateGlyphCursorCookie(cookie)
+}
+
 // Write request to wire for CreateGlyphCursor
-func (c *Conn) CreateGlyphCursor(Cid Id, SourceFont Id, MaskFont Id, SourceChar uint16, MaskChar uint16, ForeRed uint16, ForeGreen uint16, ForeBlue uint16, BackRed uint16, BackGreen uint16, BackBlue uint16) {
+func createGlyphCursorRequest(Cid Id, SourceFont Id, MaskFont Id, SourceChar uint16, MaskChar uint16, ForeRed uint16, ForeGreen uint16, ForeBlue uint16, BackRed uint16, BackGreen uint16, BackBlue uint16) []byte {
 	size := 32
 	b := 0
 	buf := make([]byte, size)
@@ -10088,13 +11602,28 @@ func (c *Conn) CreateGlyphCursor(Cid Id, SourceFont Id, MaskFont Id, SourceChar
 	Put16(buf[b:], BackBlue)
 	b += 2
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request FreeCursor
 // size: 8
+type FreeCursorCookie cookie
+
+// Write request to wire for FreeCursor
+func (c *Conn) FreeCursor(Cursor Id) FreeCursorCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(freeCursorRequest(Cursor), cookie)
+	return FreeCursorCookie(cookie)
+}
+
+func (c *Conn) FreeCursorChecked(Cursor Id) FreeCursorCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(freeCursorRequest(Cursor), cookie)
+	return FreeCursorCookie(cookie)
+}
+
 // Write request to wire for FreeCursor
-func (c *Conn) FreeCursor(Cursor Id) {
+func freeCursorRequest(Cursor Id) []byte {
 	size := 8
 	b := 0
 	buf := make([]byte, size)
@@ -10110,13 +11639,28 @@ func (c *Conn) FreeCursor(Cursor Id) {
 	Put32(buf[b:], uint32(Cursor))
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request RecolorCursor
 // size: 20
+type RecolorCursorCookie cookie
+
 // Write request to wire for RecolorCursor
-func (c *Conn) RecolorCursor(Cursor Id, ForeRed uint16, ForeGreen uint16, ForeBlue uint16, BackRed uint16, BackGreen uint16, BackBlue uint16) {
+func (c *Conn) RecolorCursor(Cursor Id, ForeRed uint16, ForeGreen uint16, ForeBlue uint16, BackRed uint16, BackGreen uint16, BackBlue uint16) RecolorCursorCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(recolorCursorRequest(Cursor, ForeRed, ForeGreen, ForeBlue, BackRed, BackGreen, BackBlue), cookie)
+	return RecolorCursorCookie(cookie)
+}
+
+func (c *Conn) RecolorCursorChecked(Cursor Id, ForeRed uint16, ForeGreen uint16, ForeBlue uint16, BackRed uint16, BackGreen uint16, BackBlue uint16) RecolorCursorCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(recolorCursorRequest(Cursor, ForeRed, ForeGreen, ForeBlue, BackRed, BackGreen, BackBlue), cookie)
+	return RecolorCursorCookie(cookie)
+}
+
+// Write request to wire for RecolorCursor
+func recolorCursorRequest(Cursor Id, ForeRed uint16, ForeGreen uint16, ForeBlue uint16, BackRed uint16, BackGreen uint16, BackBlue uint16) []byte {
 	size := 20
 	b := 0
 	buf := make([]byte, size)
@@ -10150,40 +11694,23 @@ func (c *Conn) RecolorCursor(Cursor Id, ForeRed uint16, ForeGreen uint16, ForeBl
 	Put16(buf[b:], BackBlue)
 	b += 2
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request QueryBestSize
 // size: 12
-func (c *Conn) QueryBestSize(Class byte, Drawable Id, Width uint16, Height uint16) (*QueryBestSizeReply, error) {
-	return c.QueryBestSizeReply(c.QueryBestSizeRequest(Class, Drawable, Width, Height))
-}
-
-// Write request to wire for QueryBestSize
-func (c *Conn) QueryBestSizeRequest(Class byte, Drawable Id, Width uint16, Height uint16) *Cookie {
-	size := 12
-	b := 0
-	buf := make([]byte, size)
-
-	buf[b] = 97 // request opcode
-	b += 1
-
-	buf[b] = Class
-	b += 1
+type QueryBestSizeCookie cookie
 
-	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
-	b += 2
-
-	Put32(buf[b:], uint32(Drawable))
-	b += 4
-
-	Put16(buf[b:], Width)
-	b += 2
-
-	Put16(buf[b:], Height)
-	b += 2
+func (c *Conn) QueryBestSize(Class byte, Drawable Id, Width uint16, Height uint16) QueryBestSizeCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(queryBestSizeRequest(Class, Drawable, Width, Height), cookie)
+	return QueryBestSizeCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) QueryBestSizeUnchecked(Class byte, Drawable Id, Width uint16, Height uint16) QueryBestSizeCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(queryBestSizeRequest(Class, Drawable, Width, Height), cookie)
+	return QueryBestSizeCookie(cookie)
 }
 
 // Request reply for QueryBestSize
@@ -10196,13 +11723,17 @@ type QueryBestSizeReply struct {
 	Height uint16
 }
 
-// Read reply QueryBestSize
-func (c *Conn) QueryBestSizeReply(cook *Cookie) (*QueryBestSizeReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request QueryBestSize
+func (cook QueryBestSizeCookie) Reply() (*QueryBestSizeReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return queryBestSizeReply(buf), nil
+}
 
+// Read reply into structure from buffer for QueryBestSize
+func queryBestSizeReply(buf []byte) *QueryBestSizeReply {
 	v := new(QueryBestSizeReply)
 	b := 1 // skip reply determinant
 
@@ -10220,38 +11751,50 @@ func (c *Conn) QueryBestSizeReply(cook *Cookie) (*QueryBestSizeReply, error) {
 	v.Height = Get16(buf[b:])
 	b += 2
 
-	return v, nil
-}
-
-// Request QueryExtension
-// size: (8 + pad((int(NameLen) * 1)))
-func (c *Conn) QueryExtension(NameLen uint16, Name string) (*QueryExtensionReply, error) {
-	return c.QueryExtensionReply(c.QueryExtensionRequest(NameLen, Name))
+	return v
 }
 
-// Write request to wire for QueryExtension
-func (c *Conn) QueryExtensionRequest(NameLen uint16, Name string) *Cookie {
-	size := (8 + pad((int(NameLen) * 1)))
+// Write request to wire for QueryBestSize
+func queryBestSizeRequest(Class byte, Drawable Id, Width uint16, Height uint16) []byte {
+	size := 12
 	b := 0
 	buf := make([]byte, size)
 
-	buf[b] = 98 // request opcode
+	buf[b] = 97 // request opcode
 	b += 1
 
-	b += 1 // padding
+	buf[b] = Class
+	b += 1
 
 	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
 	b += 2
 
-	Put16(buf[b:], NameLen)
+	Put32(buf[b:], uint32(Drawable))
+	b += 4
+
+	Put16(buf[b:], Width)
 	b += 2
 
-	b += 2 // padding
+	Put16(buf[b:], Height)
+	b += 2
 
-	copy(buf[b:], Name[:NameLen])
-	b += pad(int(NameLen))
+	return buf
+}
+
+// Request QueryExtension
+// size: pad((8 + pad((int(NameLen) * 1))))
+type QueryExtensionCookie cookie
+
+func (c *Conn) QueryExtension(NameLen uint16, Name string) QueryExtensionCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(queryExtensionRequest(NameLen, Name), cookie)
+	return QueryExtensionCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) QueryExtensionUnchecked(NameLen uint16, Name string) QueryExtensionCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(queryExtensionRequest(NameLen, Name), cookie)
+	return QueryExtensionCookie(cookie)
 }
 
 // Request reply for QueryExtension
@@ -10266,13 +11809,17 @@ type QueryExtensionReply struct {
 	FirstError  byte
 }
 
-// Read reply QueryExtension
-func (c *Conn) QueryExtensionReply(cook *Cookie) (*QueryExtensionReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request QueryExtension
+func (cook QueryExtensionCookie) Reply() (*QueryExtensionReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return queryExtensionReply(buf), nil
+}
 
+// Read reply into structure from buffer for QueryExtension
+func queryExtensionReply(buf []byte) *QueryExtensionReply {
 	v := new(QueryExtensionReply)
 	b := 1 // skip reply determinant
 
@@ -10300,25 +11847,48 @@ func (c *Conn) QueryExtensionReply(cook *Cookie) (*QueryExtensionReply, error) {
 	v.FirstError = buf[b]
 	b += 1
 
-	return v, nil
-}
-
-// Request ListExtensions
-// size: 3
-func (c *Conn) ListExtensions() (*ListExtensionsReply, error) {
-	return c.ListExtensionsReply(c.ListExtensionsRequest())
+	return v
 }
 
-// Write request to wire for ListExtensions
-func (c *Conn) ListExtensionsRequest() *Cookie {
-	size := 3
+// Write request to wire for QueryExtension
+func queryExtensionRequest(NameLen uint16, Name string) []byte {
+	size := pad((8 + pad((int(NameLen) * 1))))
 	b := 0
 	buf := make([]byte, size)
 
-	buf[b] = 99 // request opcode
+	buf[b] = 98 // request opcode
 	b += 1
 
-	return c.sendRequest(true, buf)
+	b += 1 // padding
+
+	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
+	b += 2
+
+	Put16(buf[b:], NameLen)
+	b += 2
+
+	b += 2 // padding
+
+	copy(buf[b:], Name[:NameLen])
+	b += pad(int(NameLen))
+
+	return buf
+}
+
+// Request ListExtensions
+// size: 4
+type ListExtensionsCookie cookie
+
+func (c *Conn) ListExtensions() ListExtensionsCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(listExtensionsRequest(), cookie)
+	return ListExtensionsCookie(cookie)
+}
+
+func (c *Conn) ListExtensionsUnchecked() ListExtensionsCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(listExtensionsRequest(), cookie)
+	return ListExtensionsCookie(cookie)
 }
 
 // Request reply for ListExtensions
@@ -10331,13 +11901,17 @@ type ListExtensionsReply struct {
 	Names []Str // size: StrListSize(Names)
 }
 
-// Read reply ListExtensions
-func (c *Conn) ListExtensionsReply(cook *Cookie) (*ListExtensionsReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request ListExtensions
+func (cook ListExtensionsCookie) Reply() (*ListExtensionsReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return listExtensionsReply(buf), nil
+}
 
+// Read reply into structure from buffer for ListExtensions
+func listExtensionsReply(buf []byte) *ListExtensionsReply {
 	v := new(ListExtensionsReply)
 	b := 1 // skip reply determinant
 
@@ -10355,14 +11929,41 @@ func (c *Conn) ListExtensionsReply(cook *Cookie) (*ListExtensionsReply, error) {
 	v.Names = make([]Str, v.NamesLen)
 	b += ReadStrList(buf[b:], v.Names)
 
-	return v, nil
+	return v
+}
+
+// Write request to wire for ListExtensions
+func listExtensionsRequest() []byte {
+	size := 4
+	b := 0
+	buf := make([]byte, size)
+
+	buf[b] = 99 // request opcode
+	b += 1
+
+	return buf
 }
 
 // Request ChangeKeyboardMapping
-// size: (8 + pad(((int(KeycodeCount) * int(KeysymsPerKeycode)) * 4)))
+// size: pad((8 + pad(((int(KeycodeCount) * int(KeysymsPerKeycode)) * 4))))
+type ChangeKeyboardMappingCookie cookie
+
 // Write request to wire for ChangeKeyboardMapping
-func (c *Conn) ChangeKeyboardMapping(KeycodeCount byte, FirstKeycode Keycode, KeysymsPerKeycode byte, Keysyms []Keysym) {
-	size := (8 + pad(((int(KeycodeCount) * int(KeysymsPerKeycode)) * 4)))
+func (c *Conn) ChangeKeyboardMapping(KeycodeCount byte, FirstKeycode Keycode, KeysymsPerKeycode byte, Keysyms []Keysym) ChangeKeyboardMappingCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(changeKeyboardMappingRequest(KeycodeCount, FirstKeycode, KeysymsPerKeycode, Keysyms), cookie)
+	return ChangeKeyboardMappingCookie(cookie)
+}
+
+func (c *Conn) ChangeKeyboardMappingChecked(KeycodeCount byte, FirstKeycode Keycode, KeysymsPerKeycode byte, Keysyms []Keysym) ChangeKeyboardMappingCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(changeKeyboardMappingRequest(KeycodeCount, FirstKeycode, KeysymsPerKeycode, Keysyms), cookie)
+	return ChangeKeyboardMappingCookie(cookie)
+}
+
+// Write request to wire for ChangeKeyboardMapping
+func changeKeyboardMappingRequest(KeycodeCount byte, FirstKeycode Keycode, KeysymsPerKeycode byte, Keysyms []Keysym) []byte {
+	size := pad((8 + pad(((int(KeycodeCount) * int(KeysymsPerKeycode)) * 4))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -10389,36 +11990,23 @@ func (c *Conn) ChangeKeyboardMapping(KeycodeCount byte, FirstKeycode Keycode, Ke
 	}
 	b = pad(b)
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request GetKeyboardMapping
-// size: 6
-func (c *Conn) GetKeyboardMapping(FirstKeycode Keycode, Count byte) (*GetKeyboardMappingReply, error) {
-	return c.GetKeyboardMappingReply(c.GetKeyboardMappingRequest(FirstKeycode, Count))
-}
-
-// Write request to wire for GetKeyboardMapping
-func (c *Conn) GetKeyboardMappingRequest(FirstKeycode Keycode, Count byte) *Cookie {
-	size := 6
-	b := 0
-	buf := make([]byte, size)
-
-	buf[b] = 101 // request opcode
-	b += 1
-
-	b += 1 // padding
-
-	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
-	b += 2
-
-	buf[b] = byte(FirstKeycode)
-	b += 1
+// size: 8
+type GetKeyboardMappingCookie cookie
 
-	buf[b] = Count
-	b += 1
+func (c *Conn) GetKeyboardMapping(FirstKeycode Keycode, Count byte) GetKeyboardMappingCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(getKeyboardMappingRequest(FirstKeycode, Count), cookie)
+	return GetKeyboardMappingCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) GetKeyboardMappingUnchecked(FirstKeycode Keycode, Count byte) GetKeyboardMappingCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(getKeyboardMappingRequest(FirstKeycode, Count), cookie)
+	return GetKeyboardMappingCookie(cookie)
 }
 
 // Request reply for GetKeyboardMapping
@@ -10431,13 +12019,17 @@ type GetKeyboardMappingReply struct {
 	Keysyms []Keysym // size: pad((int(Length) * 4))
 }
 
-// Read reply GetKeyboardMapping
-func (c *Conn) GetKeyboardMappingReply(cook *Cookie) (*GetKeyboardMappingReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request GetKeyboardMapping
+func (cook GetKeyboardMappingCookie) Reply() (*GetKeyboardMappingReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return getKeyboardMappingReply(buf), nil
+}
 
+// Read reply into structure from buffer for GetKeyboardMapping
+func getKeyboardMappingReply(buf []byte) *GetKeyboardMappingReply {
 	v := new(GetKeyboardMappingReply)
 	b := 1 // skip reply determinant
 
@@ -10459,14 +12051,52 @@ func (c *Conn) GetKeyboardMappingReply(cook *Cookie) (*GetKeyboardMappingReply,
 	}
 	b = pad(b)
 
-	return v, nil
+	return v
+}
+
+// Write request to wire for GetKeyboardMapping
+func getKeyboardMappingRequest(FirstKeycode Keycode, Count byte) []byte {
+	size := 8
+	b := 0
+	buf := make([]byte, size)
+
+	buf[b] = 101 // request opcode
+	b += 1
+
+	b += 1 // padding
+
+	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
+	b += 2
+
+	buf[b] = byte(FirstKeycode)
+	b += 1
+
+	buf[b] = Count
+	b += 1
+
+	return buf
 }
 
 // Request ChangeKeyboardControl
-// size: (4 + (4 + pad((4 * popCount(int(ValueMask))))))
+// size: pad((4 + (4 + pad((4 * popCount(int(ValueMask)))))))
+type ChangeKeyboardControlCookie cookie
+
+// Write request to wire for ChangeKeyboardControl
+func (c *Conn) ChangeKeyboardControl(ValueMask uint32, ValueList []uint32) ChangeKeyboardControlCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(changeKeyboardControlRequest(ValueMask, ValueList), cookie)
+	return ChangeKeyboardControlCookie(cookie)
+}
+
+func (c *Conn) ChangeKeyboardControlChecked(ValueMask uint32, ValueList []uint32) ChangeKeyboardControlCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(changeKeyboardControlRequest(ValueMask, ValueList), cookie)
+	return ChangeKeyboardControlCookie(cookie)
+}
+
 // Write request to wire for ChangeKeyboardControl
-func (c *Conn) ChangeKeyboardControl(ValueMask uint32, ValueList []uint32) {
-	size := (4 + (4 + pad((4 * popCount(int(ValueMask))))))
+func changeKeyboardControlRequest(ValueMask uint32, ValueList []uint32) []byte {
+	size := pad((4 + (4 + pad((4 * popCount(int(ValueMask)))))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -10486,25 +12116,23 @@ func (c *Conn) ChangeKeyboardControl(ValueMask uint32, ValueList []uint32) {
 	}
 	b = pad(b)
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request GetKeyboardControl
-// size: 3
-func (c *Conn) GetKeyboardControl() (*GetKeyboardControlReply, error) {
-	return c.GetKeyboardControlReply(c.GetKeyboardControlRequest())
-}
-
-// Write request to wire for GetKeyboardControl
-func (c *Conn) GetKeyboardControlRequest() *Cookie {
-	size := 3
-	b := 0
-	buf := make([]byte, size)
+// size: 4
+type GetKeyboardControlCookie cookie
 
-	buf[b] = 103 // request opcode
-	b += 1
+func (c *Conn) GetKeyboardControl() GetKeyboardControlCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(getKeyboardControlRequest(), cookie)
+	return GetKeyboardControlCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) GetKeyboardControlUnchecked() GetKeyboardControlCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(getKeyboardControlRequest(), cookie)
+	return GetKeyboardControlCookie(cookie)
 }
 
 // Request reply for GetKeyboardControl
@@ -10522,13 +12150,17 @@ type GetKeyboardControlReply struct {
 	AutoRepeats []byte // size: pad(32)
 }
 
-// Read reply GetKeyboardControl
-func (c *Conn) GetKeyboardControlReply(cook *Cookie) (*GetKeyboardControlReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request GetKeyboardControl
+func (cook GetKeyboardControlCookie) Reply() (*GetKeyboardControlReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return getKeyboardControlReply(buf), nil
+}
 
+// Read reply into structure from buffer for GetKeyboardControl
+func getKeyboardControlReply(buf []byte) *GetKeyboardControlReply {
 	v := new(GetKeyboardControlReply)
 	b := 1 // skip reply determinant
 
@@ -10562,13 +12194,40 @@ func (c *Conn) GetKeyboardControlReply(cook *Cookie) (*GetKeyboardControlReply,
 	copy(v.AutoRepeats[:32], buf[b:])
 	b += pad(int(32))
 
-	return v, nil
+	return v
+}
+
+// Write request to wire for GetKeyboardControl
+func getKeyboardControlRequest() []byte {
+	size := 4
+	b := 0
+	buf := make([]byte, size)
+
+	buf[b] = 103 // request opcode
+	b += 1
+
+	return buf
 }
 
 // Request Bell
 // size: 4
+type BellCookie cookie
+
+// Write request to wire for Bell
+func (c *Conn) Bell(Percent int8) BellCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(bellRequest(Percent), cookie)
+	return BellCookie(cookie)
+}
+
+func (c *Conn) BellChecked(Percent int8) BellCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(bellRequest(Percent), cookie)
+	return BellCookie(cookie)
+}
+
 // Write request to wire for Bell
-func (c *Conn) Bell(Percent int8) {
+func bellRequest(Percent int8) []byte {
 	size := 4
 	b := 0
 	buf := make([]byte, size)
@@ -10579,13 +12238,28 @@ func (c *Conn) Bell(Percent int8) {
 	buf[b] = byte(Percent)
 	b += 1
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request ChangePointerControl
 // size: 12
+type ChangePointerControlCookie cookie
+
+// Write request to wire for ChangePointerControl
+func (c *Conn) ChangePointerControl(AccelerationNumerator int16, AccelerationDenominator int16, Threshold int16, DoAcceleration bool, DoThreshold bool) ChangePointerControlCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(changePointerControlRequest(AccelerationNumerator, AccelerationDenominator, Threshold, DoAcceleration, DoThreshold), cookie)
+	return ChangePointerControlCookie(cookie)
+}
+
+func (c *Conn) ChangePointerControlChecked(AccelerationNumerator int16, AccelerationDenominator int16, Threshold int16, DoAcceleration bool, DoThreshold bool) ChangePointerControlCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(changePointerControlRequest(AccelerationNumerator, AccelerationDenominator, Threshold, DoAcceleration, DoThreshold), cookie)
+	return ChangePointerControlCookie(cookie)
+}
+
 // Write request to wire for ChangePointerControl
-func (c *Conn) ChangePointerControl(AccelerationNumerator int16, AccelerationDenominator int16, Threshold int16, DoAcceleration bool, DoThreshold bool) {
+func changePointerControlRequest(AccelerationNumerator int16, AccelerationDenominator int16, Threshold int16, DoAcceleration bool, DoThreshold bool) []byte {
 	size := 12
 	b := 0
 	buf := make([]byte, size)
@@ -10621,25 +12295,23 @@ func (c *Conn) ChangePointerControl(AccelerationNumerator int16, AccelerationDen
 	}
 	b += 1
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request GetPointerControl
-// size: 3
-func (c *Conn) GetPointerControl() (*GetPointerControlReply, error) {
-	return c.GetPointerControlReply(c.GetPointerControlRequest())
-}
-
-// Write request to wire for GetPointerControl
-func (c *Conn) GetPointerControlRequest() *Cookie {
-	size := 3
-	b := 0
-	buf := make([]byte, size)
+// size: 4
+type GetPointerControlCookie cookie
 
-	buf[b] = 106 // request opcode
-	b += 1
+func (c *Conn) GetPointerControl() GetPointerControlCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(getPointerControlRequest(), cookie)
+	return GetPointerControlCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) GetPointerControlUnchecked() GetPointerControlCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(getPointerControlRequest(), cookie)
+	return GetPointerControlCookie(cookie)
 }
 
 // Request reply for GetPointerControl
@@ -10654,13 +12326,17 @@ type GetPointerControlReply struct {
 	// padding: 18 bytes
 }
 
-// Read reply GetPointerControl
-func (c *Conn) GetPointerControlReply(cook *Cookie) (*GetPointerControlReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request GetPointerControl
+func (cook GetPointerControlCookie) Reply() (*GetPointerControlReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return getPointerControlReply(buf), nil
+}
 
+// Read reply into structure from buffer for GetPointerControl
+func getPointerControlReply(buf []byte) *GetPointerControlReply {
 	v := new(GetPointerControlReply)
 	b := 1 // skip reply determinant
 
@@ -10683,14 +12359,41 @@ func (c *Conn) GetPointerControlReply(cook *Cookie) (*GetPointerControlReply, er
 
 	b += 18 // padding
 
-	return v, nil
+	return v
+}
+
+// Write request to wire for GetPointerControl
+func getPointerControlRequest() []byte {
+	size := 4
+	b := 0
+	buf := make([]byte, size)
+
+	buf[b] = 106 // request opcode
+	b += 1
+
+	return buf
 }
 
 // Request SetScreenSaver
-// size: 10
+// size: 12
+type SetScreenSaverCookie cookie
+
+// Write request to wire for SetScreenSaver
+func (c *Conn) SetScreenSaver(Timeout int16, Interval int16, PreferBlanking byte, AllowExposures byte) SetScreenSaverCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(setScreenSaverRequest(Timeout, Interval, PreferBlanking, AllowExposures), cookie)
+	return SetScreenSaverCookie(cookie)
+}
+
+func (c *Conn) SetScreenSaverChecked(Timeout int16, Interval int16, PreferBlanking byte, AllowExposures byte) SetScreenSaverCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(setScreenSaverRequest(Timeout, Interval, PreferBlanking, AllowExposures), cookie)
+	return SetScreenSaverCookie(cookie)
+}
+
 // Write request to wire for SetScreenSaver
-func (c *Conn) SetScreenSaver(Timeout int16, Interval int16, PreferBlanking byte, AllowExposures byte) {
-	size := 10
+func setScreenSaverRequest(Timeout int16, Interval int16, PreferBlanking byte, AllowExposures byte) []byte {
+	size := 12
 	b := 0
 	buf := make([]byte, size)
 
@@ -10714,25 +12417,23 @@ func (c *Conn) SetScreenSaver(Timeout int16, Interval int16, PreferBlanking byte
 	buf[b] = AllowExposures
 	b += 1
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request GetScreenSaver
-// size: 3
-func (c *Conn) GetScreenSaver() (*GetScreenSaverReply, error) {
-	return c.GetScreenSaverReply(c.GetScreenSaverRequest())
-}
-
-// Write request to wire for GetScreenSaver
-func (c *Conn) GetScreenSaverRequest() *Cookie {
-	size := 3
-	b := 0
-	buf := make([]byte, size)
+// size: 4
+type GetScreenSaverCookie cookie
 
-	buf[b] = 108 // request opcode
-	b += 1
+func (c *Conn) GetScreenSaver() GetScreenSaverCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(getScreenSaverRequest(), cookie)
+	return GetScreenSaverCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) GetScreenSaverUnchecked() GetScreenSaverCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(getScreenSaverRequest(), cookie)
+	return GetScreenSaverCookie(cookie)
 }
 
 // Request reply for GetScreenSaver
@@ -10748,13 +12449,17 @@ type GetScreenSaverReply struct {
 	// padding: 18 bytes
 }
 
-// Read reply GetScreenSaver
-func (c *Conn) GetScreenSaverReply(cook *Cookie) (*GetScreenSaverReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request GetScreenSaver
+func (cook GetScreenSaverCookie) Reply() (*GetScreenSaverReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return getScreenSaverReply(buf), nil
+}
 
+// Read reply into structure from buffer for GetScreenSaver
+func getScreenSaverReply(buf []byte) *GetScreenSaverReply {
 	v := new(GetScreenSaverReply)
 	b := 1 // skip reply determinant
 
@@ -10780,14 +12485,41 @@ func (c *Conn) GetScreenSaverReply(cook *Cookie) (*GetScreenSaverReply, error) {
 
 	b += 18 // padding
 
-	return v, nil
+	return v
+}
+
+// Write request to wire for GetScreenSaver
+func getScreenSaverRequest() []byte {
+	size := 4
+	b := 0
+	buf := make([]byte, size)
+
+	buf[b] = 108 // request opcode
+	b += 1
+
+	return buf
 }
 
 // Request ChangeHosts
-// size: (8 + pad((int(AddressLen) * 1)))
+// size: pad((8 + pad((int(AddressLen) * 1))))
+type ChangeHostsCookie cookie
+
+// Write request to wire for ChangeHosts
+func (c *Conn) ChangeHosts(Mode byte, Family byte, AddressLen uint16, Address []byte) ChangeHostsCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(changeHostsRequest(Mode, Family, AddressLen, Address), cookie)
+	return ChangeHostsCookie(cookie)
+}
+
+func (c *Conn) ChangeHostsChecked(Mode byte, Family byte, AddressLen uint16, Address []byte) ChangeHostsCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(changeHostsRequest(Mode, Family, AddressLen, Address), cookie)
+	return ChangeHostsCookie(cookie)
+}
+
 // Write request to wire for ChangeHosts
-func (c *Conn) ChangeHosts(Mode byte, Family byte, AddressLen uint16, Address []byte) {
-	size := (8 + pad((int(AddressLen) * 1)))
+func changeHostsRequest(Mode byte, Family byte, AddressLen uint16, Address []byte) []byte {
+	size := pad((8 + pad((int(AddressLen) * 1))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -10811,25 +12543,23 @@ func (c *Conn) ChangeHosts(Mode byte, Family byte, AddressLen uint16, Address []
 	copy(buf[b:], Address[:AddressLen])
 	b += pad(int(AddressLen))
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request ListHosts
-// size: 3
-func (c *Conn) ListHosts() (*ListHostsReply, error) {
-	return c.ListHostsReply(c.ListHostsRequest())
-}
-
-// Write request to wire for ListHosts
-func (c *Conn) ListHostsRequest() *Cookie {
-	size := 3
-	b := 0
-	buf := make([]byte, size)
+// size: 4
+type ListHostsCookie cookie
 
-	buf[b] = 110 // request opcode
-	b += 1
+func (c *Conn) ListHosts() ListHostsCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(listHostsRequest(), cookie)
+	return ListHostsCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) ListHostsUnchecked() ListHostsCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(listHostsRequest(), cookie)
+	return ListHostsCookie(cookie)
 }
 
 // Request reply for ListHosts
@@ -10843,13 +12573,17 @@ type ListHostsReply struct {
 	Hosts []Host // size: HostListSize(Hosts)
 }
 
-// Read reply ListHosts
-func (c *Conn) ListHostsReply(cook *Cookie) (*ListHostsReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request ListHosts
+func (cook ListHostsCookie) Reply() (*ListHostsReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return listHostsReply(buf), nil
+}
 
+// Read reply into structure from buffer for ListHosts
+func listHostsReply(buf []byte) *ListHostsReply {
 	v := new(ListHostsReply)
 	b := 1 // skip reply determinant
 
@@ -10870,13 +12604,40 @@ func (c *Conn) ListHostsReply(cook *Cookie) (*ListHostsReply, error) {
 	v.Hosts = make([]Host, v.HostsLen)
 	b += ReadHostList(buf[b:], v.Hosts)
 
-	return v, nil
+	return v
+}
+
+// Write request to wire for ListHosts
+func listHostsRequest() []byte {
+	size := 4
+	b := 0
+	buf := make([]byte, size)
+
+	buf[b] = 110 // request opcode
+	b += 1
+
+	return buf
 }
 
 // Request SetAccessControl
 // size: 4
+type SetAccessControlCookie cookie
+
 // Write request to wire for SetAccessControl
-func (c *Conn) SetAccessControl(Mode byte) {
+func (c *Conn) SetAccessControl(Mode byte) SetAccessControlCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(setAccessControlRequest(Mode), cookie)
+	return SetAccessControlCookie(cookie)
+}
+
+func (c *Conn) SetAccessControlChecked(Mode byte) SetAccessControlCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(setAccessControlRequest(Mode), cookie)
+	return SetAccessControlCookie(cookie)
+}
+
+// Write request to wire for SetAccessControl
+func setAccessControlRequest(Mode byte) []byte {
 	size := 4
 	b := 0
 	buf := make([]byte, size)
@@ -10887,13 +12648,28 @@ func (c *Conn) SetAccessControl(Mode byte) {
 	buf[b] = Mode
 	b += 1
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request SetCloseDownMode
 // size: 4
+type SetCloseDownModeCookie cookie
+
 // Write request to wire for SetCloseDownMode
-func (c *Conn) SetCloseDownMode(Mode byte) {
+func (c *Conn) SetCloseDownMode(Mode byte) SetCloseDownModeCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(setCloseDownModeRequest(Mode), cookie)
+	return SetCloseDownModeCookie(cookie)
+}
+
+func (c *Conn) SetCloseDownModeChecked(Mode byte) SetCloseDownModeCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(setCloseDownModeRequest(Mode), cookie)
+	return SetCloseDownModeCookie(cookie)
+}
+
+// Write request to wire for SetCloseDownMode
+func setCloseDownModeRequest(Mode byte) []byte {
 	size := 4
 	b := 0
 	buf := make([]byte, size)
@@ -10904,13 +12680,28 @@ func (c *Conn) SetCloseDownMode(Mode byte) {
 	buf[b] = Mode
 	b += 1
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request KillClient
 // size: 8
+type KillClientCookie cookie
+
+// Write request to wire for KillClient
+func (c *Conn) KillClient(Resource uint32) KillClientCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(killClientRequest(Resource), cookie)
+	return KillClientCookie(cookie)
+}
+
+func (c *Conn) KillClientChecked(Resource uint32) KillClientCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(killClientRequest(Resource), cookie)
+	return KillClientCookie(cookie)
+}
+
 // Write request to wire for KillClient
-func (c *Conn) KillClient(Resource uint32) {
+func killClientRequest(Resource uint32) []byte {
 	size := 8
 	b := 0
 	buf := make([]byte, size)
@@ -10926,14 +12717,29 @@ func (c *Conn) KillClient(Resource uint32) {
 	Put32(buf[b:], Resource)
 	b += 4
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request RotateProperties
-// size: (12 + pad((int(AtomsLen) * 4)))
+// size: pad((12 + pad((int(AtomsLen) * 4))))
+type RotatePropertiesCookie cookie
+
 // Write request to wire for RotateProperties
-func (c *Conn) RotateProperties(Window Id, AtomsLen uint16, Delta int16, Atoms []Id) {
-	size := (12 + pad((int(AtomsLen) * 4)))
+func (c *Conn) RotateProperties(Window Id, AtomsLen uint16, Delta int16, Atoms []Id) RotatePropertiesCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(rotatePropertiesRequest(Window, AtomsLen, Delta, Atoms), cookie)
+	return RotatePropertiesCookie(cookie)
+}
+
+func (c *Conn) RotatePropertiesChecked(Window Id, AtomsLen uint16, Delta int16, Atoms []Id) RotatePropertiesCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(rotatePropertiesRequest(Window, AtomsLen, Delta, Atoms), cookie)
+	return RotatePropertiesCookie(cookie)
+}
+
+// Write request to wire for RotateProperties
+func rotatePropertiesRequest(Window Id, AtomsLen uint16, Delta int16, Atoms []Id) []byte {
+	size := pad((12 + pad((int(AtomsLen) * 4))))
 	b := 0
 	buf := make([]byte, size)
 
@@ -10960,13 +12766,28 @@ func (c *Conn) RotateProperties(Window Id, AtomsLen uint16, Delta int16, Atoms [
 	}
 	b = pad(b)
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request ForceScreenSaver
 // size: 4
+type ForceScreenSaverCookie cookie
+
+// Write request to wire for ForceScreenSaver
+func (c *Conn) ForceScreenSaver(Mode byte) ForceScreenSaverCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(forceScreenSaverRequest(Mode), cookie)
+	return ForceScreenSaverCookie(cookie)
+}
+
+func (c *Conn) ForceScreenSaverChecked(Mode byte) ForceScreenSaverCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(forceScreenSaverRequest(Mode), cookie)
+	return ForceScreenSaverCookie(cookie)
+}
+
 // Write request to wire for ForceScreenSaver
-func (c *Conn) ForceScreenSaver(Mode byte) {
+func forceScreenSaverRequest(Mode byte) []byte {
 	size := 4
 	b := 0
 	buf := make([]byte, size)
@@ -10977,34 +12798,23 @@ func (c *Conn) ForceScreenSaver(Mode byte) {
 	buf[b] = Mode
 	b += 1
 
-	c.sendRequest(false, buf)
+	return buf
 }
 
 // Request SetPointerMapping
-// size: (4 + pad((int(MapLen) * 1)))
-func (c *Conn) SetPointerMapping(MapLen byte, Map []byte) (*SetPointerMappingReply, error) {
-	return c.SetPointerMappingReply(c.SetPointerMappingRequest(MapLen, Map))
-}
-
-// Write request to wire for SetPointerMapping
-func (c *Conn) SetPointerMappingRequest(MapLen byte, Map []byte) *Cookie {
-	size := (4 + pad((int(MapLen) * 1)))
-	b := 0
-	buf := make([]byte, size)
-
-	buf[b] = 116 // request opcode
-	b += 1
+// size: pad((4 + pad((int(MapLen) * 1))))
+type SetPointerMappingCookie cookie
 
-	buf[b] = MapLen
-	b += 1
-
-	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
-	b += 2
-
-	copy(buf[b:], Map[:MapLen])
-	b += pad(int(MapLen))
+func (c *Conn) SetPointerMapping(MapLen byte, Map []byte) SetPointerMappingCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(setPointerMappingRequest(MapLen, Map), cookie)
+	return SetPointerMappingCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) SetPointerMappingUnchecked(MapLen byte, Map []byte) SetPointerMappingCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(setPointerMappingRequest(MapLen, Map), cookie)
+	return SetPointerMappingCookie(cookie)
 }
 
 // Request reply for SetPointerMapping
@@ -11015,38 +12825,61 @@ type SetPointerMappingReply struct {
 	Status   byte
 }
 
-// Read reply SetPointerMapping
-func (c *Conn) SetPointerMappingReply(cook *Cookie) (*SetPointerMappingReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request SetPointerMapping
+func (cook SetPointerMappingCookie) Reply() (*SetPointerMappingReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return setPointerMappingReply(buf), nil
+}
 
+// Read reply into structure from buffer for SetPointerMapping
+func setPointerMappingReply(buf []byte) *SetPointerMappingReply {
 	v := new(SetPointerMappingReply)
 	b := 1 // skip reply determinant
 
 	v.Status = buf[b]
 	b += 1
 
-	return v, nil
-}
-
-// Request GetPointerMapping
-// size: 3
-func (c *Conn) GetPointerMapping() (*GetPointerMappingReply, error) {
-	return c.GetPointerMappingReply(c.GetPointerMappingRequest())
+	return v
 }
 
-// Write request to wire for GetPointerMapping
-func (c *Conn) GetPointerMappingRequest() *Cookie {
-	size := 3
+// Write request to wire for SetPointerMapping
+func setPointerMappingRequest(MapLen byte, Map []byte) []byte {
+	size := pad((4 + pad((int(MapLen) * 1))))
 	b := 0
 	buf := make([]byte, size)
 
-	buf[b] = 117 // request opcode
+	buf[b] = 116 // request opcode
 	b += 1
 
-	return c.sendRequest(true, buf)
+	buf[b] = MapLen
+	b += 1
+
+	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
+	b += 2
+
+	copy(buf[b:], Map[:MapLen])
+	b += pad(int(MapLen))
+
+	return buf
+}
+
+// Request GetPointerMapping
+// size: 4
+type GetPointerMappingCookie cookie
+
+func (c *Conn) GetPointerMapping() GetPointerMappingCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(getPointerMappingRequest(), cookie)
+	return GetPointerMappingCookie(cookie)
+}
+
+func (c *Conn) GetPointerMappingUnchecked() GetPointerMappingCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(getPointerMappingRequest(), cookie)
+	return GetPointerMappingCookie(cookie)
 }
 
 // Request reply for GetPointerMapping
@@ -11059,13 +12892,17 @@ type GetPointerMappingReply struct {
 	Map []byte // size: pad((int(MapLen) * 1))
 }
 
-// Read reply GetPointerMapping
-func (c *Conn) GetPointerMappingReply(cook *Cookie) (*GetPointerMappingReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request GetPointerMapping
+func (cook GetPointerMappingCookie) Reply() (*GetPointerMappingReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return getPointerMappingReply(buf), nil
+}
 
+// Read reply into structure from buffer for GetPointerMapping
+func getPointerMappingReply(buf []byte) *GetPointerMappingReply {
 	v := new(GetPointerMappingReply)
 	b := 1 // skip reply determinant
 
@@ -11084,37 +12921,35 @@ func (c *Conn) GetPointerMappingReply(cook *Cookie) (*GetPointerMappingReply, er
 	copy(v.Map[:v.MapLen], buf[b:])
 	b += pad(int(v.MapLen))
 
-	return v, nil
-}
-
-// Request SetModifierMapping
-// size: (4 + pad(((int(KeycodesPerModifier) * 8) * 1)))
-func (c *Conn) SetModifierMapping(KeycodesPerModifier byte, Keycodes []Keycode) (*SetModifierMappingReply, error) {
-	return c.SetModifierMappingReply(c.SetModifierMappingRequest(KeycodesPerModifier, Keycodes))
+	return v
 }
 
-// Write request to wire for SetModifierMapping
-func (c *Conn) SetModifierMappingRequest(KeycodesPerModifier byte, Keycodes []Keycode) *Cookie {
-	size := (4 + pad(((int(KeycodesPerModifier) * 8) * 1)))
+// Write request to wire for GetPointerMapping
+func getPointerMappingRequest() []byte {
+	size := 4
 	b := 0
 	buf := make([]byte, size)
 
-	buf[b] = 118 // request opcode
+	buf[b] = 117 // request opcode
 	b += 1
 
-	buf[b] = KeycodesPerModifier
-	b += 1
+	return buf
+}
 
-	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
-	b += 2
+// Request SetModifierMapping
+// size: pad((4 + pad(((int(KeycodesPerModifier) * 8) * 1))))
+type SetModifierMappingCookie cookie
 
-	for i := 0; i < int((int(KeycodesPerModifier) * 8)); i++ {
-		buf[b] = byte(Keycodes[i])
-		b += 1
-	}
-	b = pad(b)
+func (c *Conn) SetModifierMapping(KeycodesPerModifier byte, Keycodes []Keycode) SetModifierMappingCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(setModifierMappingRequest(KeycodesPerModifier, Keycodes), cookie)
+	return SetModifierMappingCookie(cookie)
+}
 
-	return c.sendRequest(true, buf)
+func (c *Conn) SetModifierMappingUnchecked(KeycodesPerModifier byte, Keycodes []Keycode) SetModifierMappingCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(setModifierMappingRequest(KeycodesPerModifier, Keycodes), cookie)
+	return SetModifierMappingCookie(cookie)
 }
 
 // Request reply for SetModifierMapping
@@ -11125,38 +12960,64 @@ type SetModifierMappingReply struct {
 	Status   byte
 }
 
-// Read reply SetModifierMapping
-func (c *Conn) SetModifierMappingReply(cook *Cookie) (*SetModifierMappingReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request SetModifierMapping
+func (cook SetModifierMappingCookie) Reply() (*SetModifierMappingReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return setModifierMappingReply(buf), nil
+}
 
+// Read reply into structure from buffer for SetModifierMapping
+func setModifierMappingReply(buf []byte) *SetModifierMappingReply {
 	v := new(SetModifierMappingReply)
 	b := 1 // skip reply determinant
 
 	v.Status = buf[b]
 	b += 1
 
-	return v, nil
-}
-
-// Request GetModifierMapping
-// size: 3
-func (c *Conn) GetModifierMapping() (*GetModifierMappingReply, error) {
-	return c.GetModifierMappingReply(c.GetModifierMappingRequest())
+	return v
 }
 
-// Write request to wire for GetModifierMapping
-func (c *Conn) GetModifierMappingRequest() *Cookie {
-	size := 3
+// Write request to wire for SetModifierMapping
+func setModifierMappingRequest(KeycodesPerModifier byte, Keycodes []Keycode) []byte {
+	size := pad((4 + pad(((int(KeycodesPerModifier) * 8) * 1))))
 	b := 0
 	buf := make([]byte, size)
 
-	buf[b] = 119 // request opcode
+	buf[b] = 118 // request opcode
+	b += 1
+
+	buf[b] = KeycodesPerModifier
 	b += 1
 
-	return c.sendRequest(true, buf)
+	Put16(buf[b:], uint16(size/4)) // write request size in 4-byte units
+	b += 2
+
+	for i := 0; i < int((int(KeycodesPerModifier) * 8)); i++ {
+		buf[b] = byte(Keycodes[i])
+		b += 1
+	}
+	b = pad(b)
+
+	return buf
+}
+
+// Request GetModifierMapping
+// size: 4
+type GetModifierMappingCookie cookie
+
+func (c *Conn) GetModifierMapping() GetModifierMappingCookie {
+	cookie := c.newCookie(true, true)
+	c.newRequest(getModifierMappingRequest(), cookie)
+	return GetModifierMappingCookie(cookie)
+}
+
+func (c *Conn) GetModifierMappingUnchecked() GetModifierMappingCookie {
+	cookie := c.newCookie(false, true)
+	c.newRequest(getModifierMappingRequest(), cookie)
+	return GetModifierMappingCookie(cookie)
 }
 
 // Request reply for GetModifierMapping
@@ -11169,13 +13030,17 @@ type GetModifierMappingReply struct {
 	Keycodes []Keycode // size: pad(((int(KeycodesPerModifier) * 8) * 1))
 }
 
-// Read reply GetModifierMapping
-func (c *Conn) GetModifierMappingReply(cook *Cookie) (*GetModifierMappingReply, error) {
-	buf, err := c.waitForReply(cook)
+// Waits and reads reply data from request GetModifierMapping
+func (cook GetModifierMappingCookie) Reply() (*GetModifierMappingReply, error) {
+	buf, err := cookie(cook).reply()
 	if err != nil {
 		return nil, err
 	}
+	return getModifierMappingReply(buf), nil
+}
 
+// Read reply into structure from buffer for GetModifierMapping
+func getModifierMappingReply(buf []byte) *GetModifierMappingReply {
 	v := new(GetModifierMappingReply)
 	b := 1 // skip reply determinant
 
@@ -11197,19 +13062,46 @@ func (c *Conn) GetModifierMappingReply(cook *Cookie) (*GetModifierMappingReply,
 	}
 	b = pad(b)
 
-	return v, nil
+	return v
+}
+
+// Write request to wire for GetModifierMapping
+func getModifierMappingRequest() []byte {
+	size := 4
+	b := 0
+	buf := make([]byte, size)
+
+	buf[b] = 119 // request opcode
+	b += 1
+
+	return buf
 }
 
 // Request NoOperation
-// size: 3
+// size: 4
+type NoOperationCookie cookie
+
 // Write request to wire for NoOperation
-func (c *Conn) NoOperation() {
-	size := 3
+func (c *Conn) NoOperation() NoOperationCookie {
+	cookie := c.newCookie(false, false)
+	c.newRequest(noOperationRequest(), cookie)
+	return NoOperationCookie(cookie)
+}
+
+func (c *Conn) NoOperationChecked() NoOperationCookie {
+	cookie := c.newCookie(true, false)
+	c.newRequest(noOperationRequest(), cookie)
+	return NoOperationCookie(cookie)
+}
+
+// Write request to wire for NoOperation
+func noOperationRequest() []byte {
+	size := 4
 	b := 0
 	buf := make([]byte, size)
 
 	buf[b] = 127 // request opcode
 	b += 1
 
-	c.sendRequest(false, buf)
+	return buf
 }