return 0, e.err
	}

	// Leading fringe.
	if e.nbuf > 0 {
		var i int
		for i = 0; i < len(p) && e.nbuf < 5; i++ {
			e.buf[e.nbuf] = p[i]
			e.nbuf++
		}
		n += i
		p = p[i:]
		if e.nbuf < 5 {
			return
		}
		e.enc.Encode(e.out[0:], e.buf[0:])
		if _, e.err = e.w.Write(e.out[0:8]); e.err != nil {
			return n, e.err
		}
		e.nbuf = 0
	}

	// Large interior chunks.

		decoder := NewDecoder(StdEncoding, &br)
		dbuf := make([]byte, StdEncoding.DecodedLen(len(input)))
		n, err := decoder.Read(dbuf)
		testEqual(t, "Decoding of %q err = %v, expected %v", input, err, error(nil))
		n, err = decoder.Read(dbuf)
		testEqual(t, "Read after EOF, n = %d, expected %d", n, 0)
		testEqual(t, "Read after EOF, err = %v, expected %v", err, io.EOF)
		n, err = decoder.Read(dbuf)

const (
	bufSize = 4096
)

var buf [bufSize]byte
var nbuf uintptr

func dwrite(data unsafe.Pointer, len uintptr) {
	if len == 0 {
		return
	}
	if nbuf+len <= bufSize {
		copy(buf[nbuf:], (*[bufSize]byte)(data)[:len])
		nbuf += len
		return
	}

	write(dumpfd, unsafe.Pointer(&buf), int32(nbuf))
	if len >= bufSize {
		write(dumpfd, data, int32(len))
		nbuf = 0
	} else {

		return utf8.AppendRune(buf, r)
	}
	switch r {
	case '\a':
		buf = append(buf, `\a`...)
	case '\b':
		buf = append(buf, `\b`...)
	case '\f':
		buf = append(buf, `\f`...)
	case '\n':
		buf = append(buf, `\n`...)
	case '\r':
		buf = append(buf, `\r`...)
	case '\t':
		buf = append(buf, `\t`...)
	case '\v':
		buf = append(buf, `\v`...)
	default:
		switch {

			}
			fatalf(msg+": %v", err)
		}
		var buf bytes.Buffer
		buf.WriteString("HTTP/1.1 200 OK\r\n")
		if test.chunked {
			buf.WriteString("Transfer-Encoding: chunked\r\n")
		} else {
			buf.WriteString("Content-Length: 1000000\r\n")
		}
		var wr io.Writer = &buf
		if test.chunked {
			wr = internal.NewChunkedWriter(wr)
		}
		if test.compressed {
			buf.WriteString("Content-Encoding: gzip\r\n")

	if err != nil {
		return x, buf, err
	}
	x.metaVer, buf, err = msgp.ReadUintBytes(buf)
	if err != nil {
		return x, buf, err
	}
	if x.headerVer > xlHeaderVersion {
		return x, buf, fmt.Errorf("decodeXLHeaders: Unknown xl header version %d", x.headerVer)
	}
	if x.metaVer > xlMetaVersion {
		return x, buf, fmt.Errorf("decodeXLHeaders: Unknown xl meta version %d", x.metaVer)
	}

}

func direntIno(buf []byte) (uint64, bool) {
	return readInt(buf, unsafe.Offsetof(Dirent{}.Ino), unsafe.Sizeof(Dirent{}.Ino))
}

func direntReclen(buf []byte) (uint64, bool) {
	return readInt(buf, unsafe.Offsetof(Dirent{}.Reclen), unsafe.Sizeof(Dirent{}.Reclen))
}

func direntNamlen(buf []byte) (uint64, bool) {
	reclen, ok := direntReclen(buf)
	if !ok {
		return 0, false
	}

	raw    RawSockaddrDatalink
}

func direntIno(buf []byte) (uint64, bool) {
	return readInt(buf, unsafe.Offsetof(Dirent{}.Ino), unsafe.Sizeof(Dirent{}.Ino))
}

func direntReclen(buf []byte) (uint64, bool) {
	return readInt(buf, unsafe.Offsetof(Dirent{}.Reclen), unsafe.Sizeof(Dirent{}.Reclen))
}

func direntNamlen(buf []byte) (uint64, bool) {
	reclen, ok := direntReclen(buf)
	if !ok {
		return 0, false
	}

	buf, err := readSpecialFile(r)
	if err != nil {
		return nil, err
	}
	sbuf := string(buf)

	// For GNU PAX sparse format 0.0 support.
	// This function transforms the sparse format 0.0 headers into format 0.1
	// headers since 0.0 headers were not PAX compliant.
	var sparseMap []string

	paxHdrs := make(map[string]string)
	for len(sbuf) > 0 {

		// we drop the lock.
		trace.workAvailable.Store(false)
		unlock(&trace.lock)
		return nil, true
	}
	// Pull a buffer.
	tbuf := trace.full[gen%2].pop()
	trace.reading = tbuf
	unlock(&trace.lock)
	return tbuf.arr[:tbuf.pos], false
}

// traceReader returns the trace reader that should be woken up, if any.
// Callers should first check (traceEnabled() || traceShuttingDown()).
//