w.pc.nwrite += int64(n)
	return
}

// ReadFrom exposes persistConnWriter's underlying Conn to io.Copy and if
// the Conn implements io.ReaderFrom, it can take advantage of optimizations
// such as sendfile.
func (w persistConnWriter) ReadFrom(r io.Reader) (n int64, err error) {
	n, err = io.Copy(w.pc.conn, r)
	w.pc.nwrite += n
	return
}

var _ io.ReaderFrom = (*persistConnWriter)(nil)

// from io.Copy.
type writerOnly struct {
	io.Writer
}

// ReadFrom is here to optimize copying from an [*os.File] regular file
// to a [*net.TCPConn] with sendfile, or from a supported src type such
// as a *net.TCPConn on Linux with splice.
func (w *response) ReadFrom(src io.Reader) (n int64, err error) {
	buf := getCopyBuf()
	defer putCopyBuf(buf)

		"Total number of XDS responses from pilot rejected by proxy.",
	)

	ResponseWriteTimeouts = monitoring.NewSum(
		"pilot_xds_write_timeout",
		"Pilot XDS response write timeouts.",
	)

	sendTime = monitoring.NewDistribution(
		"pilot_xds_send_time",
		"Total time in seconds Pilot takes to send generated configuration.",
		[]float64{.01, .1, 1, 3, 5, 10, 20, 30},
	)
)

	}
	w := when(d)
	return resetTimer(t, w, 0)
}

// sendTime does a non-blocking send of the current time on c.
func sendTime(c any, seq uintptr, delta int64) {
	// delta is how long ago the channel send was supposed to happen.
	// The current time can be arbitrarily far into the future, because the runtime
	// can delay a sendTime call until a goroutines tries to receive from

	endSpecs := pos[len(pos)-1].End
	beg := fset.File(begSpecs).LineStart(lineAt(fset, begSpecs))
	endLine := lineAt(fset, endSpecs)
	endFile := fset.File(endSpecs)
	var end token.Pos
	if endLine == endFile.LineCount() {
		end = endSpecs
	} else {
		end = endFile.LineStart(endLine + 1) // beginning of next line
	}
	first := len(f.Comments)
	last := -1
	for i, g := range f.Comments {
		if g.End() >= end {

		if _, err := content.Seek(ra.start, io.SeekStart); err != nil {
			serveError(w, err.Error(), StatusRequestedRangeNotSatisfiable)
			return
		}
		sendSize = ra.length
		code = StatusPartialContent
		w.Header().Set("Content-Range", ra.contentRange(size))
	case len(ranges) > 1:
		sendSize = rangesMIMESize(ranges, ctype, size)
		code = StatusPartialContent

		pr, pw := io.Pipe()
		mw := multipart.NewWriter(pw)

	// If the client falls behind while reading, we drop ticks
	// on the floor until the client catches up.
	c := make(chan Time, 1)
	t := (*Ticker)(unsafe.Pointer(newTimer(when(d), int64(d), sendTime, c, syncTimer(c))))
	t.C = c
	return t
}

// Stop turns off a ticker. After Stop, no more ticks will be sent.
// Stop does not close the channel, to prevent a concurrent goroutine

	Inits    uint32
	Rmx      RtMetrics
}

type RtMetrics struct {
	Pksent   uint64
	Expire   int64
	Locks    uint32
	Mtu      uint32
	Refcnt   uint32
	Hopcount uint32
	Recvpipe uint32
	Sendpipe uint32
	Ssthresh uint32
	Rtt      uint32
	Rttvar   uint32
	Pad      uint32
}

type Mclpool struct{}

const (
	SizeofBpfVersion = 0x4
	SizeofBpfStat    = 0x8
	SizeofBpfProgram = 0x10

	Inits    uint32
	Rmx      RtMetrics
}

type RtMetrics struct {
	Pksent   uint64
	Expire   int64
	Locks    uint32
	Mtu      uint32
	Refcnt   uint32
	Hopcount uint32
	Recvpipe uint32
	Sendpipe uint32
	Ssthresh uint32
	Rtt      uint32
	Rttvar   uint32
	Pad      uint32
}

type Mclpool struct{}

const (
	SizeofBpfVersion = 0x4
	SizeofBpfStat    = 0x8
	SizeofBpfProgram = 0x10

	Errno   int32
	Use     int32
	Inits   uint32
	Rmx     RtMetrics
}

type RtMetrics struct {
	Locks    uint32
	Mtu      uint32
	Hopcount uint32
	Expire   uint32
	Recvpipe uint32
	Sendpipe uint32
	Ssthresh uint32
	Rtt      uint32
	Rttvar   uint32
	Pksent   uint32
}

const (
	SizeofBpfVersion = 0x4
	SizeofBpfStat    = 0x80
	SizeofBpfProgram = 0x10
	SizeofBpfInsn    = 0x8