RET

TEXT runtime·pwrite(SB),NOSPLIT,$0
	MOVQ	$51, BP
	SYSCALL
	MOVL	AX, ret+32(FP)
	RET

// int32 _seek(int64*, int32, int64, int32)
TEXT _seek<>(SB),NOSPLIT,$0
	MOVQ	$39, BP
	SYSCALL
	RET

// int64 seek(int32, int64, int32)
// Convenience wrapper around _seek, the actual system call.
TEXT runtime·seek(SB),NOSPLIT,$32
	LEAQ	ret+24(FP), AX
	MOVL	fd+0(FP), BX
	MOVQ	offset+8(FP), CX

	RET

#define SYS__LLSEEK 140	/* from zsysnum_linux_386.go */
// func Seek(fd int, offset int64, whence int) (newoffset int64, err int)
// Implemented in assembly to avoid allocation when
// taking the address of the return value newoffset.
// Underlying system call is
//	llseek(int fd, int offhi, int offlo, int64 *result, int whence)
TEXT ·seek(SB),NOSPLIT,$0-28
	CALL	runtime·entersyscall(SB)
	MOVL	$SYS__LLSEEK, AX	// syscall entry

	}
	_, err = ws.Seek(int64(len(ws.BytesWritten())+1), io.SeekStart)
	if err == nil {
		t.Fatalf("expected error on invalid %d seek", len(ws.BytesWritten()))
	}

	ws.Seek(0, io.SeekStart)
	_, err = ws.Seek(-1, io.SeekCurrent)
	if err == nil {
		t.Fatalf("expected error on invalid -1 seek")
	}
	_, err = ws.Seek(int64(len(ws.BytesWritten())+1), io.SeekCurrent)
	if err == nil {

	}
	copy(towrite, p)
	sws.off += int64(amt)
	return amt, nil
}

// Seek repositions the read/write position of the WriteSeeker within
// its internally maintained slice. Note that it is not possible to
// expand the size of the slice using SEEK_SET; trying to seek outside
// the slice will result in an error.
func (sws *WriteSeeker) Seek(offset int64, whence int) (int64, error) {
	switch whence {
	case io.SeekStart:

	o := &fd.wop
	o.handle = src

	// TODO(brainman): skip calling syscall.Seek if OS allows it
	curpos, err := syscall.Seek(o.handle, 0, io.SeekCurrent)
	if err != nil {
		return 0, err
	}

	if n <= 0 { // We don't know the size of the file so infer it.
		// Find the number of bytes offset from curpos until the end of the file.
		n, err = syscall.Seek(o.handle, -curpos, io.SeekEnd)
		if err != nil {
			return
		}

			if off, err := r.Seek(+1, 1); off != int64(middle) || err != nil {
				return fmt.Errorf("Seek(+1, 1) from %d = %d, %v, want %d, nil", middle-1, off, err, middle)
			}
		}

		// Seek(0, 1) should report the current file position (middle).
		if off, err := r.Seek(0, 1); off != int64(middle) || err != nil {
			return fmt.Errorf("Seek(0, 1) from %d = %d, %v, want %d, nil", middle, off, err, middle)
		}

		{seek: io.SeekCurrent, off: 1, wantpos: 1<<33 + 1, readerr: io.EOF},
		{seek: io.SeekStart, n: 5, want: "01234"},
		{seek: io.SeekCurrent, n: 5, want: "56789"},
		{seek: io.SeekEnd, off: -1, n: 1, wantpos: 9, want: "9"},
	}

	for i, tt := range tests {
		pos, err := r.Seek(tt.off, tt.seek)
		if err == nil && tt.seekerr != "" {
			t.Errorf("%d. want seek error %q", i, tt.seekerr)
			continue
		}

type Section struct {
	SectionHeader
	Relocs []Reloc

	// Embed ReaderAt for ReadAt method.
	// Do not embed SectionReader directly
	// to avoid having Read and Seek.
	// If a client wants Read and Seek it must use
	// Open() to avoid fighting over the seek offset
	// with other clients.
	io.ReaderAt
	sr *io.SectionReader
}

// Data reads and returns the contents of the PE section s.
//

                try ( SmbRandomAccessFile raf = new SmbRandomAccessFile(f, "r") ) {
                    raf.seek(10);
                    Assert.assertEquals(-1, raf.read());
                }

                byte[] buf = new byte[4];
                try ( SmbRandomAccessFile raf = new SmbRandomAccessFile(f, "r") ) {
                    raf.seek(6);
                    Assert.assertEquals(2, raf.read(buf));

        output.done()

        then:
        file.length() == 5
        file.seek(0)
        file.readInt() == 123
        file.readByte() == 12

        when:
        stream = output.start(5)
        stream.writeInt(321)
        output.done()

        then:
        file.length() == 9
        file.seek(0)
        file.readInt() == 123
        file.readByte() == 12
        file.readInt() == 321