| // Copyright 2009 The Go Authors. All rights reserved. | 
 | // Use of this source code is governed by a BSD-style | 
 | // license that can be found in the LICENSE file. | 
 |  | 
 | // Linux system calls. | 
 | // This file is compiled as ordinary Go code, | 
 | // but it is also input to mksyscall, | 
 | // which parses the //sys lines and generates system call stubs. | 
 | // Note that sometimes we use a lowercase //sys name and | 
 | // wrap it in our own nicer implementation. | 
 |  | 
 | package syscall | 
 |  | 
 | import "unsafe" | 
 |  | 
 | func rawSyscallNoError(trap, a1, a2, a3 uintptr) (r1, r2 uintptr) | 
 |  | 
 | /* | 
 |  * Wrapped | 
 |  */ | 
 |  | 
 | func Access(path string, mode uint32) (err error) { | 
 | 	return Faccessat(_AT_FDCWD, path, mode, 0) | 
 | } | 
 |  | 
 | func Chmod(path string, mode uint32) (err error) { | 
 | 	return Fchmodat(_AT_FDCWD, path, mode, 0) | 
 | } | 
 |  | 
 | func Chown(path string, uid int, gid int) (err error) { | 
 | 	return Fchownat(_AT_FDCWD, path, uid, gid, 0) | 
 | } | 
 |  | 
 | func Creat(path string, mode uint32) (fd int, err error) { | 
 | 	return Open(path, O_CREAT|O_WRONLY|O_TRUNC, mode) | 
 | } | 
 |  | 
 | //sys	faccessat(dirfd int, path string, mode uint32) (err error) | 
 |  | 
 | func Faccessat(dirfd int, path string, mode uint32, flags int) (err error) { | 
 | 	if flags & ^(_AT_SYMLINK_NOFOLLOW|_AT_EACCESS) != 0 { | 
 | 		return EINVAL | 
 | 	} else if flags&(_AT_SYMLINK_NOFOLLOW|_AT_EACCESS) != 0 { | 
 | 		return EOPNOTSUPP | 
 | 	} | 
 | 	return faccessat(dirfd, path, mode) | 
 | } | 
 |  | 
 | //sys	fchmodat(dirfd int, path string, mode uint32) (err error) | 
 |  | 
 | func Fchmodat(dirfd int, path string, mode uint32, flags int) (err error) { | 
 | 	// Linux fchmodat doesn't support the flags parameter. Mimick glibc's behavior | 
 | 	// and check the flags. Otherwise the mode would be applied to the symlink | 
 | 	// destination which is not what the user expects. | 
 | 	if flags&^_AT_SYMLINK_NOFOLLOW != 0 { | 
 | 		return EINVAL | 
 | 	} else if flags&_AT_SYMLINK_NOFOLLOW != 0 { | 
 | 		return EOPNOTSUPP | 
 | 	} | 
 | 	return fchmodat(dirfd, path, mode) | 
 | } | 
 |  | 
 | //sys	linkat(olddirfd int, oldpath string, newdirfd int, newpath string, flags int) (err error) | 
 |  | 
 | func Link(oldpath string, newpath string) (err error) { | 
 | 	return linkat(_AT_FDCWD, oldpath, _AT_FDCWD, newpath, 0) | 
 | } | 
 |  | 
 | func Mkdir(path string, mode uint32) (err error) { | 
 | 	return Mkdirat(_AT_FDCWD, path, mode) | 
 | } | 
 |  | 
 | func Mknod(path string, mode uint32, dev int) (err error) { | 
 | 	return Mknodat(_AT_FDCWD, path, mode, dev) | 
 | } | 
 |  | 
 | func Open(path string, mode int, perm uint32) (fd int, err error) { | 
 | 	return openat(_AT_FDCWD, path, mode|O_LARGEFILE, perm) | 
 | } | 
 |  | 
 | //sys	openat(dirfd int, path string, flags int, mode uint32) (fd int, err error) | 
 |  | 
 | func Openat(dirfd int, path string, flags int, mode uint32) (fd int, err error) { | 
 | 	return openat(dirfd, path, flags|O_LARGEFILE, mode) | 
 | } | 
 |  | 
 | //sys	readlinkat(dirfd int, path string, buf []byte) (n int, err error) | 
 |  | 
 | func Readlink(path string, buf []byte) (n int, err error) { | 
 | 	return readlinkat(_AT_FDCWD, path, buf) | 
 | } | 
 |  | 
 | func Rename(oldpath string, newpath string) (err error) { | 
 | 	return Renameat(_AT_FDCWD, oldpath, _AT_FDCWD, newpath) | 
 | } | 
 |  | 
 | func Rmdir(path string) error { | 
 | 	return unlinkat(_AT_FDCWD, path, _AT_REMOVEDIR) | 
 | } | 
 |  | 
 | //sys	symlinkat(oldpath string, newdirfd int, newpath string) (err error) | 
 |  | 
 | func Symlink(oldpath string, newpath string) (err error) { | 
 | 	return symlinkat(oldpath, _AT_FDCWD, newpath) | 
 | } | 
 |  | 
 | func Unlink(path string) error { | 
 | 	return unlinkat(_AT_FDCWD, path, 0) | 
 | } | 
 |  | 
 | //sys	unlinkat(dirfd int, path string, flags int) (err error) | 
 |  | 
 | func Unlinkat(dirfd int, path string) error { | 
 | 	return unlinkat(dirfd, path, 0) | 
 | } | 
 |  | 
 | //sys	utimes(path string, times *[2]Timeval) (err error) | 
 |  | 
 | func Utimes(path string, tv []Timeval) (err error) { | 
 | 	if len(tv) != 2 { | 
 | 		return EINVAL | 
 | 	} | 
 | 	return utimes(path, (*[2]Timeval)(unsafe.Pointer(&tv[0]))) | 
 | } | 
 |  | 
 | //sys	utimensat(dirfd int, path string, times *[2]Timespec, flag int) (err error) | 
 |  | 
 | func UtimesNano(path string, ts []Timespec) (err error) { | 
 | 	if len(ts) != 2 { | 
 | 		return EINVAL | 
 | 	} | 
 | 	err = utimensat(_AT_FDCWD, path, (*[2]Timespec)(unsafe.Pointer(&ts[0])), 0) | 
 | 	if err != ENOSYS { | 
 | 		return err | 
 | 	} | 
 | 	// If the utimensat syscall isn't available (utimensat was added to Linux | 
 | 	// in 2.6.22, Released, 8 July 2007) then fall back to utimes | 
 | 	var tv [2]Timeval | 
 | 	for i := 0; i < 2; i++ { | 
 | 		tv[i].Sec = ts[i].Sec | 
 | 		tv[i].Usec = ts[i].Nsec / 1000 | 
 | 	} | 
 | 	return utimes(path, (*[2]Timeval)(unsafe.Pointer(&tv[0]))) | 
 | } | 
 |  | 
 | //sys	futimesat(dirfd int, path *byte, times *[2]Timeval) (err error) | 
 |  | 
 | func Futimesat(dirfd int, path string, tv []Timeval) (err error) { | 
 | 	if len(tv) != 2 { | 
 | 		return EINVAL | 
 | 	} | 
 | 	pathp, err := BytePtrFromString(path) | 
 | 	if err != nil { | 
 | 		return err | 
 | 	} | 
 | 	return futimesat(dirfd, pathp, (*[2]Timeval)(unsafe.Pointer(&tv[0]))) | 
 | } | 
 |  | 
 | func Futimes(fd int, tv []Timeval) (err error) { | 
 | 	// Believe it or not, this is the best we can do on Linux | 
 | 	// (and is what glibc does). | 
 | 	return Utimes("/proc/self/fd/"+itoa(fd), tv) | 
 | } | 
 |  | 
 | const ImplementsGetwd = true | 
 |  | 
 | //sys	Getcwd(buf []byte) (n int, err error) | 
 |  | 
 | func Getwd() (wd string, err error) { | 
 | 	var buf [PathMax]byte | 
 | 	n, err := Getcwd(buf[0:]) | 
 | 	if err != nil { | 
 | 		return "", err | 
 | 	} | 
 | 	// Getcwd returns the number of bytes written to buf, including the NUL. | 
 | 	if n < 1 || n > len(buf) || buf[n-1] != 0 { | 
 | 		return "", EINVAL | 
 | 	} | 
 | 	return string(buf[0 : n-1]), nil | 
 | } | 
 |  | 
 | func Getgroups() (gids []int, err error) { | 
 | 	n, err := getgroups(0, nil) | 
 | 	if err != nil { | 
 | 		return nil, err | 
 | 	} | 
 | 	if n == 0 { | 
 | 		return nil, nil | 
 | 	} | 
 |  | 
 | 	// Sanity check group count. Max is 1<<16 on Linux. | 
 | 	if n < 0 || n > 1<<20 { | 
 | 		return nil, EINVAL | 
 | 	} | 
 |  | 
 | 	a := make([]_Gid_t, n) | 
 | 	n, err = getgroups(n, &a[0]) | 
 | 	if err != nil { | 
 | 		return nil, err | 
 | 	} | 
 | 	gids = make([]int, n) | 
 | 	for i, v := range a[0:n] { | 
 | 		gids[i] = int(v) | 
 | 	} | 
 | 	return | 
 | } | 
 |  | 
 | func Setgroups(gids []int) (err error) { | 
 | 	if len(gids) == 0 { | 
 | 		return setgroups(0, nil) | 
 | 	} | 
 |  | 
 | 	a := make([]_Gid_t, len(gids)) | 
 | 	for i, v := range gids { | 
 | 		a[i] = _Gid_t(v) | 
 | 	} | 
 | 	return setgroups(len(a), &a[0]) | 
 | } | 
 |  | 
 | type WaitStatus uint32 | 
 |  | 
 | // Wait status is 7 bits at bottom, either 0 (exited), | 
 | // 0x7F (stopped), or a signal number that caused an exit. | 
 | // The 0x80 bit is whether there was a core dump. | 
 | // An extra number (exit code, signal causing a stop) | 
 | // is in the high bits. At least that's the idea. | 
 | // There are various irregularities. For example, the | 
 | // "continued" status is 0xFFFF, distinguishing itself | 
 | // from stopped via the core dump bit. | 
 |  | 
 | const ( | 
 | 	mask    = 0x7F | 
 | 	core    = 0x80 | 
 | 	exited  = 0x00 | 
 | 	stopped = 0x7F | 
 | 	shift   = 8 | 
 | ) | 
 |  | 
 | func (w WaitStatus) Exited() bool { return w&mask == exited } | 
 |  | 
 | func (w WaitStatus) Signaled() bool { return w&mask != stopped && w&mask != exited } | 
 |  | 
 | func (w WaitStatus) Stopped() bool { return w&0xFF == stopped } | 
 |  | 
 | func (w WaitStatus) Continued() bool { return w == 0xFFFF } | 
 |  | 
 | func (w WaitStatus) CoreDump() bool { return w.Signaled() && w&core != 0 } | 
 |  | 
 | func (w WaitStatus) ExitStatus() int { | 
 | 	if !w.Exited() { | 
 | 		return -1 | 
 | 	} | 
 | 	return int(w>>shift) & 0xFF | 
 | } | 
 |  | 
 | func (w WaitStatus) Signal() Signal { | 
 | 	if !w.Signaled() { | 
 | 		return -1 | 
 | 	} | 
 | 	return Signal(w & mask) | 
 | } | 
 |  | 
 | func (w WaitStatus) StopSignal() Signal { | 
 | 	if !w.Stopped() { | 
 | 		return -1 | 
 | 	} | 
 | 	return Signal(w>>shift) & 0xFF | 
 | } | 
 |  | 
 | func (w WaitStatus) TrapCause() int { | 
 | 	if w.StopSignal() != SIGTRAP { | 
 | 		return -1 | 
 | 	} | 
 | 	return int(w>>shift) >> 8 | 
 | } | 
 |  | 
 | //sys	wait4(pid int, wstatus *_C_int, options int, rusage *Rusage) (wpid int, err error) | 
 |  | 
 | func Wait4(pid int, wstatus *WaitStatus, options int, rusage *Rusage) (wpid int, err error) { | 
 | 	var status _C_int | 
 | 	wpid, err = wait4(pid, &status, options, rusage) | 
 | 	if wstatus != nil { | 
 | 		*wstatus = WaitStatus(status) | 
 | 	} | 
 | 	return | 
 | } | 
 |  | 
 | func Mkfifo(path string, mode uint32) (err error) { | 
 | 	return Mknod(path, mode|S_IFIFO, 0) | 
 | } | 
 |  | 
 | func (sa *SockaddrInet4) sockaddr() (unsafe.Pointer, _Socklen, error) { | 
 | 	if sa.Port < 0 || sa.Port > 0xFFFF { | 
 | 		return nil, 0, EINVAL | 
 | 	} | 
 | 	sa.raw.Family = AF_INET | 
 | 	p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port)) | 
 | 	p[0] = byte(sa.Port >> 8) | 
 | 	p[1] = byte(sa.Port) | 
 | 	for i := 0; i < len(sa.Addr); i++ { | 
 | 		sa.raw.Addr[i] = sa.Addr[i] | 
 | 	} | 
 | 	return unsafe.Pointer(&sa.raw), SizeofSockaddrInet4, nil | 
 | } | 
 |  | 
 | func (sa *SockaddrInet6) sockaddr() (unsafe.Pointer, _Socklen, error) { | 
 | 	if sa.Port < 0 || sa.Port > 0xFFFF { | 
 | 		return nil, 0, EINVAL | 
 | 	} | 
 | 	sa.raw.Family = AF_INET6 | 
 | 	p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port)) | 
 | 	p[0] = byte(sa.Port >> 8) | 
 | 	p[1] = byte(sa.Port) | 
 | 	sa.raw.Scope_id = sa.ZoneId | 
 | 	for i := 0; i < len(sa.Addr); i++ { | 
 | 		sa.raw.Addr[i] = sa.Addr[i] | 
 | 	} | 
 | 	return unsafe.Pointer(&sa.raw), SizeofSockaddrInet6, nil | 
 | } | 
 |  | 
 | func (sa *SockaddrUnix) sockaddr() (unsafe.Pointer, _Socklen, error) { | 
 | 	name := sa.Name | 
 | 	n := len(name) | 
 | 	if n > len(sa.raw.Path) { | 
 | 		return nil, 0, EINVAL | 
 | 	} | 
 | 	if n == len(sa.raw.Path) && name[0] != '@' { | 
 | 		return nil, 0, EINVAL | 
 | 	} | 
 | 	sa.raw.Family = AF_UNIX | 
 | 	for i := 0; i < n; i++ { | 
 | 		sa.raw.Path[i] = int8(name[i]) | 
 | 	} | 
 | 	// length is family (uint16), name, NUL. | 
 | 	sl := _Socklen(2) | 
 | 	if n > 0 { | 
 | 		sl += _Socklen(n) + 1 | 
 | 	} | 
 | 	if sa.raw.Path[0] == '@' { | 
 | 		sa.raw.Path[0] = 0 | 
 | 		// Don't count trailing NUL for abstract address. | 
 | 		sl-- | 
 | 	} | 
 |  | 
 | 	return unsafe.Pointer(&sa.raw), sl, nil | 
 | } | 
 |  | 
 | type SockaddrLinklayer struct { | 
 | 	Protocol uint16 | 
 | 	Ifindex  int | 
 | 	Hatype   uint16 | 
 | 	Pkttype  uint8 | 
 | 	Halen    uint8 | 
 | 	Addr     [8]byte | 
 | 	raw      RawSockaddrLinklayer | 
 | } | 
 |  | 
 | func (sa *SockaddrLinklayer) sockaddr() (unsafe.Pointer, _Socklen, error) { | 
 | 	if sa.Ifindex < 0 || sa.Ifindex > 0x7fffffff { | 
 | 		return nil, 0, EINVAL | 
 | 	} | 
 | 	sa.raw.Family = AF_PACKET | 
 | 	sa.raw.Protocol = sa.Protocol | 
 | 	sa.raw.Ifindex = int32(sa.Ifindex) | 
 | 	sa.raw.Hatype = sa.Hatype | 
 | 	sa.raw.Pkttype = sa.Pkttype | 
 | 	sa.raw.Halen = sa.Halen | 
 | 	for i := 0; i < len(sa.Addr); i++ { | 
 | 		sa.raw.Addr[i] = sa.Addr[i] | 
 | 	} | 
 | 	return unsafe.Pointer(&sa.raw), SizeofSockaddrLinklayer, nil | 
 | } | 
 |  | 
 | type SockaddrNetlink struct { | 
 | 	Family uint16 | 
 | 	Pad    uint16 | 
 | 	Pid    uint32 | 
 | 	Groups uint32 | 
 | 	raw    RawSockaddrNetlink | 
 | } | 
 |  | 
 | func (sa *SockaddrNetlink) sockaddr() (unsafe.Pointer, _Socklen, error) { | 
 | 	sa.raw.Family = AF_NETLINK | 
 | 	sa.raw.Pad = sa.Pad | 
 | 	sa.raw.Pid = sa.Pid | 
 | 	sa.raw.Groups = sa.Groups | 
 | 	return unsafe.Pointer(&sa.raw), SizeofSockaddrNetlink, nil | 
 | } | 
 |  | 
 | func anyToSockaddr(rsa *RawSockaddrAny) (Sockaddr, error) { | 
 | 	switch rsa.Addr.Family { | 
 | 	case AF_NETLINK: | 
 | 		pp := (*RawSockaddrNetlink)(unsafe.Pointer(rsa)) | 
 | 		sa := new(SockaddrNetlink) | 
 | 		sa.Family = pp.Family | 
 | 		sa.Pad = pp.Pad | 
 | 		sa.Pid = pp.Pid | 
 | 		sa.Groups = pp.Groups | 
 | 		return sa, nil | 
 |  | 
 | 	case AF_PACKET: | 
 | 		pp := (*RawSockaddrLinklayer)(unsafe.Pointer(rsa)) | 
 | 		sa := new(SockaddrLinklayer) | 
 | 		sa.Protocol = pp.Protocol | 
 | 		sa.Ifindex = int(pp.Ifindex) | 
 | 		sa.Hatype = pp.Hatype | 
 | 		sa.Pkttype = pp.Pkttype | 
 | 		sa.Halen = pp.Halen | 
 | 		for i := 0; i < len(sa.Addr); i++ { | 
 | 			sa.Addr[i] = pp.Addr[i] | 
 | 		} | 
 | 		return sa, nil | 
 |  | 
 | 	case AF_UNIX: | 
 | 		pp := (*RawSockaddrUnix)(unsafe.Pointer(rsa)) | 
 | 		sa := new(SockaddrUnix) | 
 | 		if pp.Path[0] == 0 { | 
 | 			// "Abstract" Unix domain socket. | 
 | 			// Rewrite leading NUL as @ for textual display. | 
 | 			// (This is the standard convention.) | 
 | 			// Not friendly to overwrite in place, | 
 | 			// but the callers below don't care. | 
 | 			pp.Path[0] = '@' | 
 | 		} | 
 |  | 
 | 		// Assume path ends at NUL. | 
 | 		// This is not technically the Linux semantics for | 
 | 		// abstract Unix domain sockets--they are supposed | 
 | 		// to be uninterpreted fixed-size binary blobs--but | 
 | 		// everyone uses this convention. | 
 | 		n := 0 | 
 | 		for n < len(pp.Path) && pp.Path[n] != 0 { | 
 | 			n++ | 
 | 		} | 
 | 		bytes := (*[10000]byte)(unsafe.Pointer(&pp.Path[0]))[0:n] | 
 | 		sa.Name = string(bytes) | 
 | 		return sa, nil | 
 |  | 
 | 	case AF_INET: | 
 | 		pp := (*RawSockaddrInet4)(unsafe.Pointer(rsa)) | 
 | 		sa := new(SockaddrInet4) | 
 | 		p := (*[2]byte)(unsafe.Pointer(&pp.Port)) | 
 | 		sa.Port = int(p[0])<<8 + int(p[1]) | 
 | 		for i := 0; i < len(sa.Addr); i++ { | 
 | 			sa.Addr[i] = pp.Addr[i] | 
 | 		} | 
 | 		return sa, nil | 
 |  | 
 | 	case AF_INET6: | 
 | 		pp := (*RawSockaddrInet6)(unsafe.Pointer(rsa)) | 
 | 		sa := new(SockaddrInet6) | 
 | 		p := (*[2]byte)(unsafe.Pointer(&pp.Port)) | 
 | 		sa.Port = int(p[0])<<8 + int(p[1]) | 
 | 		sa.ZoneId = pp.Scope_id | 
 | 		for i := 0; i < len(sa.Addr); i++ { | 
 | 			sa.Addr[i] = pp.Addr[i] | 
 | 		} | 
 | 		return sa, nil | 
 | 	} | 
 | 	return nil, EAFNOSUPPORT | 
 | } | 
 |  | 
 | func Accept(fd int) (nfd int, sa Sockaddr, err error) { | 
 | 	var rsa RawSockaddrAny | 
 | 	var len _Socklen = SizeofSockaddrAny | 
 | 	nfd, err = accept(fd, &rsa, &len) | 
 | 	if err != nil { | 
 | 		return | 
 | 	} | 
 | 	sa, err = anyToSockaddr(&rsa) | 
 | 	if err != nil { | 
 | 		Close(nfd) | 
 | 		nfd = 0 | 
 | 	} | 
 | 	return | 
 | } | 
 |  | 
 | func Accept4(fd int, flags int) (nfd int, sa Sockaddr, err error) { | 
 | 	var rsa RawSockaddrAny | 
 | 	var len _Socklen = SizeofSockaddrAny | 
 | 	nfd, err = accept4(fd, &rsa, &len, flags) | 
 | 	if err != nil { | 
 | 		return | 
 | 	} | 
 | 	if len > SizeofSockaddrAny { | 
 | 		panic("RawSockaddrAny too small") | 
 | 	} | 
 | 	sa, err = anyToSockaddr(&rsa) | 
 | 	if err != nil { | 
 | 		Close(nfd) | 
 | 		nfd = 0 | 
 | 	} | 
 | 	return | 
 | } | 
 |  | 
 | func Getsockname(fd int) (sa Sockaddr, err error) { | 
 | 	var rsa RawSockaddrAny | 
 | 	var len _Socklen = SizeofSockaddrAny | 
 | 	if err = getsockname(fd, &rsa, &len); err != nil { | 
 | 		return | 
 | 	} | 
 | 	return anyToSockaddr(&rsa) | 
 | } | 
 |  | 
 | func GetsockoptInet4Addr(fd, level, opt int) (value [4]byte, err error) { | 
 | 	vallen := _Socklen(4) | 
 | 	err = getsockopt(fd, level, opt, unsafe.Pointer(&value[0]), &vallen) | 
 | 	return value, err | 
 | } | 
 |  | 
 | func GetsockoptIPMreq(fd, level, opt int) (*IPMreq, error) { | 
 | 	var value IPMreq | 
 | 	vallen := _Socklen(SizeofIPMreq) | 
 | 	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen) | 
 | 	return &value, err | 
 | } | 
 |  | 
 | func GetsockoptIPMreqn(fd, level, opt int) (*IPMreqn, error) { | 
 | 	var value IPMreqn | 
 | 	vallen := _Socklen(SizeofIPMreqn) | 
 | 	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen) | 
 | 	return &value, err | 
 | } | 
 |  | 
 | func GetsockoptIPv6Mreq(fd, level, opt int) (*IPv6Mreq, error) { | 
 | 	var value IPv6Mreq | 
 | 	vallen := _Socklen(SizeofIPv6Mreq) | 
 | 	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen) | 
 | 	return &value, err | 
 | } | 
 |  | 
 | func GetsockoptIPv6MTUInfo(fd, level, opt int) (*IPv6MTUInfo, error) { | 
 | 	var value IPv6MTUInfo | 
 | 	vallen := _Socklen(SizeofIPv6MTUInfo) | 
 | 	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen) | 
 | 	return &value, err | 
 | } | 
 |  | 
 | func GetsockoptICMPv6Filter(fd, level, opt int) (*ICMPv6Filter, error) { | 
 | 	var value ICMPv6Filter | 
 | 	vallen := _Socklen(SizeofICMPv6Filter) | 
 | 	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen) | 
 | 	return &value, err | 
 | } | 
 |  | 
 | func GetsockoptUcred(fd, level, opt int) (*Ucred, error) { | 
 | 	var value Ucred | 
 | 	vallen := _Socklen(SizeofUcred) | 
 | 	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen) | 
 | 	return &value, err | 
 | } | 
 |  | 
 | func SetsockoptIPMreqn(fd, level, opt int, mreq *IPMreqn) (err error) { | 
 | 	return setsockopt(fd, level, opt, unsafe.Pointer(mreq), unsafe.Sizeof(*mreq)) | 
 | } | 
 |  | 
 | func Recvmsg(fd int, p, oob []byte, flags int) (n, oobn int, recvflags int, from Sockaddr, err error) { | 
 | 	var msg Msghdr | 
 | 	var rsa RawSockaddrAny | 
 | 	msg.Name = (*byte)(unsafe.Pointer(&rsa)) | 
 | 	msg.Namelen = uint32(SizeofSockaddrAny) | 
 | 	var iov Iovec | 
 | 	if len(p) > 0 { | 
 | 		iov.Base = &p[0] | 
 | 		iov.SetLen(len(p)) | 
 | 	} | 
 | 	var dummy byte | 
 | 	if len(oob) > 0 { | 
 | 		if len(p) == 0 { | 
 | 			var sockType int | 
 | 			sockType, err = GetsockoptInt(fd, SOL_SOCKET, SO_TYPE) | 
 | 			if err != nil { | 
 | 				return | 
 | 			} | 
 | 			// receive at least one normal byte | 
 | 			if sockType != SOCK_DGRAM { | 
 | 				iov.Base = &dummy | 
 | 				iov.SetLen(1) | 
 | 			} | 
 | 		} | 
 | 		msg.Control = &oob[0] | 
 | 		msg.SetControllen(len(oob)) | 
 | 	} | 
 | 	msg.Iov = &iov | 
 | 	msg.Iovlen = 1 | 
 | 	if n, err = recvmsg(fd, &msg, flags); err != nil { | 
 | 		return | 
 | 	} | 
 | 	oobn = int(msg.Controllen) | 
 | 	recvflags = int(msg.Flags) | 
 | 	// source address is only specified if the socket is unconnected | 
 | 	if rsa.Addr.Family != AF_UNSPEC { | 
 | 		from, err = anyToSockaddr(&rsa) | 
 | 	} | 
 | 	return | 
 | } | 
 |  | 
 | func Sendmsg(fd int, p, oob []byte, to Sockaddr, flags int) (err error) { | 
 | 	_, err = SendmsgN(fd, p, oob, to, flags) | 
 | 	return | 
 | } | 
 |  | 
 | func SendmsgN(fd int, p, oob []byte, to Sockaddr, flags int) (n int, err error) { | 
 | 	var ptr unsafe.Pointer | 
 | 	var salen _Socklen | 
 | 	if to != nil { | 
 | 		var err error | 
 | 		ptr, salen, err = to.sockaddr() | 
 | 		if err != nil { | 
 | 			return 0, err | 
 | 		} | 
 | 	} | 
 | 	var msg Msghdr | 
 | 	msg.Name = (*byte)(ptr) | 
 | 	msg.Namelen = uint32(salen) | 
 | 	var iov Iovec | 
 | 	if len(p) > 0 { | 
 | 		iov.Base = &p[0] | 
 | 		iov.SetLen(len(p)) | 
 | 	} | 
 | 	var dummy byte | 
 | 	if len(oob) > 0 { | 
 | 		if len(p) == 0 { | 
 | 			var sockType int | 
 | 			sockType, err = GetsockoptInt(fd, SOL_SOCKET, SO_TYPE) | 
 | 			if err != nil { | 
 | 				return 0, err | 
 | 			} | 
 | 			// send at least one normal byte | 
 | 			if sockType != SOCK_DGRAM { | 
 | 				iov.Base = &dummy | 
 | 				iov.SetLen(1) | 
 | 			} | 
 | 		} | 
 | 		msg.Control = &oob[0] | 
 | 		msg.SetControllen(len(oob)) | 
 | 	} | 
 | 	msg.Iov = &iov | 
 | 	msg.Iovlen = 1 | 
 | 	if n, err = sendmsg(fd, &msg, flags); err != nil { | 
 | 		return 0, err | 
 | 	} | 
 | 	if len(oob) > 0 && len(p) == 0 { | 
 | 		n = 0 | 
 | 	} | 
 | 	return n, nil | 
 | } | 
 |  | 
 | // BindToDevice binds the socket associated with fd to device. | 
 | func BindToDevice(fd int, device string) (err error) { | 
 | 	return SetsockoptString(fd, SOL_SOCKET, SO_BINDTODEVICE, device) | 
 | } | 
 |  | 
 | //sys	ptrace(request int, pid int, addr uintptr, data uintptr) (err error) | 
 |  | 
 | func ptracePeek(req int, pid int, addr uintptr, out []byte) (count int, err error) { | 
 | 	// The peek requests are machine-size oriented, so we wrap it | 
 | 	// to retrieve arbitrary-length data. | 
 |  | 
 | 	// The ptrace syscall differs from glibc's ptrace. | 
 | 	// Peeks returns the word in *data, not as the return value. | 
 |  | 
 | 	var buf [sizeofPtr]byte | 
 |  | 
 | 	// Leading edge. PEEKTEXT/PEEKDATA don't require aligned | 
 | 	// access (PEEKUSER warns that it might), but if we don't | 
 | 	// align our reads, we might straddle an unmapped page | 
 | 	// boundary and not get the bytes leading up to the page | 
 | 	// boundary. | 
 | 	n := 0 | 
 | 	if addr%sizeofPtr != 0 { | 
 | 		err = ptrace(req, pid, addr-addr%sizeofPtr, uintptr(unsafe.Pointer(&buf[0]))) | 
 | 		if err != nil { | 
 | 			return 0, err | 
 | 		} | 
 | 		n += copy(out, buf[addr%sizeofPtr:]) | 
 | 		out = out[n:] | 
 | 	} | 
 |  | 
 | 	// Remainder. | 
 | 	for len(out) > 0 { | 
 | 		// We use an internal buffer to guarantee alignment. | 
 | 		// It's not documented if this is necessary, but we're paranoid. | 
 | 		err = ptrace(req, pid, addr+uintptr(n), uintptr(unsafe.Pointer(&buf[0]))) | 
 | 		if err != nil { | 
 | 			return n, err | 
 | 		} | 
 | 		copied := copy(out, buf[0:]) | 
 | 		n += copied | 
 | 		out = out[copied:] | 
 | 	} | 
 |  | 
 | 	return n, nil | 
 | } | 
 |  | 
 | func PtracePeekText(pid int, addr uintptr, out []byte) (count int, err error) { | 
 | 	return ptracePeek(PTRACE_PEEKTEXT, pid, addr, out) | 
 | } | 
 |  | 
 | func PtracePeekData(pid int, addr uintptr, out []byte) (count int, err error) { | 
 | 	return ptracePeek(PTRACE_PEEKDATA, pid, addr, out) | 
 | } | 
 |  | 
 | func ptracePoke(pokeReq int, peekReq int, pid int, addr uintptr, data []byte) (count int, err error) { | 
 | 	// As for ptracePeek, we need to align our accesses to deal | 
 | 	// with the possibility of straddling an invalid page. | 
 |  | 
 | 	// Leading edge. | 
 | 	n := 0 | 
 | 	if addr%sizeofPtr != 0 { | 
 | 		var buf [sizeofPtr]byte | 
 | 		err = ptrace(peekReq, pid, addr-addr%sizeofPtr, uintptr(unsafe.Pointer(&buf[0]))) | 
 | 		if err != nil { | 
 | 			return 0, err | 
 | 		} | 
 | 		n += copy(buf[addr%sizeofPtr:], data) | 
 | 		word := *((*uintptr)(unsafe.Pointer(&buf[0]))) | 
 | 		err = ptrace(pokeReq, pid, addr-addr%sizeofPtr, word) | 
 | 		if err != nil { | 
 | 			return 0, err | 
 | 		} | 
 | 		data = data[n:] | 
 | 	} | 
 |  | 
 | 	// Interior. | 
 | 	for len(data) > sizeofPtr { | 
 | 		word := *((*uintptr)(unsafe.Pointer(&data[0]))) | 
 | 		err = ptrace(pokeReq, pid, addr+uintptr(n), word) | 
 | 		if err != nil { | 
 | 			return n, err | 
 | 		} | 
 | 		n += sizeofPtr | 
 | 		data = data[sizeofPtr:] | 
 | 	} | 
 |  | 
 | 	// Trailing edge. | 
 | 	if len(data) > 0 { | 
 | 		var buf [sizeofPtr]byte | 
 | 		err = ptrace(peekReq, pid, addr+uintptr(n), uintptr(unsafe.Pointer(&buf[0]))) | 
 | 		if err != nil { | 
 | 			return n, err | 
 | 		} | 
 | 		copy(buf[0:], data) | 
 | 		word := *((*uintptr)(unsafe.Pointer(&buf[0]))) | 
 | 		err = ptrace(pokeReq, pid, addr+uintptr(n), word) | 
 | 		if err != nil { | 
 | 			return n, err | 
 | 		} | 
 | 		n += len(data) | 
 | 	} | 
 |  | 
 | 	return n, nil | 
 | } | 
 |  | 
 | func PtracePokeText(pid int, addr uintptr, data []byte) (count int, err error) { | 
 | 	return ptracePoke(PTRACE_POKETEXT, PTRACE_PEEKTEXT, pid, addr, data) | 
 | } | 
 |  | 
 | func PtracePokeData(pid int, addr uintptr, data []byte) (count int, err error) { | 
 | 	return ptracePoke(PTRACE_POKEDATA, PTRACE_PEEKDATA, pid, addr, data) | 
 | } | 
 |  | 
 | func PtraceGetRegs(pid int, regsout *PtraceRegs) (err error) { | 
 | 	return ptrace(PTRACE_GETREGS, pid, 0, uintptr(unsafe.Pointer(regsout))) | 
 | } | 
 |  | 
 | func PtraceSetRegs(pid int, regs *PtraceRegs) (err error) { | 
 | 	return ptrace(PTRACE_SETREGS, pid, 0, uintptr(unsafe.Pointer(regs))) | 
 | } | 
 |  | 
 | func PtraceSetOptions(pid int, options int) (err error) { | 
 | 	return ptrace(PTRACE_SETOPTIONS, pid, 0, uintptr(options)) | 
 | } | 
 |  | 
 | func PtraceGetEventMsg(pid int) (msg uint, err error) { | 
 | 	var data _C_long | 
 | 	err = ptrace(PTRACE_GETEVENTMSG, pid, 0, uintptr(unsafe.Pointer(&data))) | 
 | 	msg = uint(data) | 
 | 	return | 
 | } | 
 |  | 
 | func PtraceCont(pid int, signal int) (err error) { | 
 | 	return ptrace(PTRACE_CONT, pid, 0, uintptr(signal)) | 
 | } | 
 |  | 
 | func PtraceSyscall(pid int, signal int) (err error) { | 
 | 	return ptrace(PTRACE_SYSCALL, pid, 0, uintptr(signal)) | 
 | } | 
 |  | 
 | func PtraceSingleStep(pid int) (err error) { return ptrace(PTRACE_SINGLESTEP, pid, 0, 0) } | 
 |  | 
 | func PtraceAttach(pid int) (err error) { return ptrace(PTRACE_ATTACH, pid, 0, 0) } | 
 |  | 
 | func PtraceDetach(pid int) (err error) { return ptrace(PTRACE_DETACH, pid, 0, 0) } | 
 |  | 
 | //sys	reboot(magic1 uint, magic2 uint, cmd int, arg string) (err error) | 
 |  | 
 | func Reboot(cmd int) (err error) { | 
 | 	return reboot(LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2, cmd, "") | 
 | } | 
 |  | 
 | func ReadDirent(fd int, buf []byte) (n int, err error) { | 
 | 	return Getdents(fd, buf) | 
 | } | 
 |  | 
 | 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 | 
 | 	} | 
 | 	return reclen - uint64(unsafe.Offsetof(Dirent{}.Name)), true | 
 | } | 
 |  | 
 | //sys	mount(source string, target string, fstype string, flags uintptr, data *byte) (err error) | 
 |  | 
 | func Mount(source string, target string, fstype string, flags uintptr, data string) (err error) { | 
 | 	// Certain file systems get rather angry and EINVAL if you give | 
 | 	// them an empty string of data, rather than NULL. | 
 | 	if data == "" { | 
 | 		return mount(source, target, fstype, flags, nil) | 
 | 	} | 
 | 	datap, err := BytePtrFromString(data) | 
 | 	if err != nil { | 
 | 		return err | 
 | 	} | 
 | 	return mount(source, target, fstype, flags, datap) | 
 | } | 
 |  | 
 | // Sendto | 
 | // Recvfrom | 
 | // Socketpair | 
 |  | 
 | /* | 
 |  * Direct access | 
 |  */ | 
 | //sys	Acct(path string) (err error) | 
 | //sys	Adjtimex(buf *Timex) (state int, err error) | 
 | //sys	Chdir(path string) (err error) | 
 | //sys	Chroot(path string) (err error) | 
 | //sys	Close(fd int) (err error) | 
 | //sys	Dup(oldfd int) (fd int, err error) | 
 | //sys	Dup3(oldfd int, newfd int, flags int) (err error) | 
 | //sysnb	EpollCreate(size int) (fd int, err error) | 
 | //sysnb	EpollCreate1(flag int) (fd int, err error) | 
 | //sysnb	EpollCtl(epfd int, op int, fd int, event *EpollEvent) (err error) | 
 | //sys	Fallocate(fd int, mode uint32, off int64, len int64) (err error) | 
 | //sys	Fchdir(fd int) (err error) | 
 | //sys	Fchmod(fd int, mode uint32) (err error) | 
 | //sys	Fchownat(dirfd int, path string, uid int, gid int, flags int) (err error) | 
 | //sys	fcntl(fd int, cmd int, arg int) (val int, err error) | 
 | //sys	Fdatasync(fd int) (err error) | 
 | //sys	Flock(fd int, how int) (err error) | 
 | //sys	Fsync(fd int) (err error) | 
 | //sys	Getdents(fd int, buf []byte) (n int, err error) = SYS_GETDENTS64 | 
 | //sysnb	Getpgid(pid int) (pgid int, err error) | 
 |  | 
 | func Getpgrp() (pid int) { | 
 | 	pid, _ = Getpgid(0) | 
 | 	return | 
 | } | 
 |  | 
 | //sysnb	Getpid() (pid int) | 
 | //sysnb	Getppid() (ppid int) | 
 | //sys	Getpriority(which int, who int) (prio int, err error) | 
 | //sysnb	Getrusage(who int, rusage *Rusage) (err error) | 
 | //sysnb	Gettid() (tid int) | 
 | //sys	Getxattr(path string, attr string, dest []byte) (sz int, err error) | 
 | //sys	InotifyAddWatch(fd int, pathname string, mask uint32) (watchdesc int, err error) | 
 | //sysnb	InotifyInit1(flags int) (fd int, err error) | 
 | //sysnb	InotifyRmWatch(fd int, watchdesc uint32) (success int, err error) | 
 | //sysnb	Kill(pid int, sig Signal) (err error) | 
 | //sys	Klogctl(typ int, buf []byte) (n int, err error) = SYS_SYSLOG | 
 | //sys	Listxattr(path string, dest []byte) (sz int, err error) | 
 | //sys	Mkdirat(dirfd int, path string, mode uint32) (err error) | 
 | //sys	Mknodat(dirfd int, path string, mode uint32, dev int) (err error) | 
 | //sys	Nanosleep(time *Timespec, leftover *Timespec) (err error) | 
 | //sys	Pause() (err error) | 
 | //sys	PivotRoot(newroot string, putold string) (err error) = SYS_PIVOT_ROOT | 
 | //sysnb prlimit(pid int, resource int, newlimit *Rlimit, old *Rlimit) (err error) = SYS_PRLIMIT64 | 
 | //sys	read(fd int, p []byte) (n int, err error) | 
 | //sys	Removexattr(path string, attr string) (err error) | 
 | //sys	Renameat(olddirfd int, oldpath string, newdirfd int, newpath string) (err error) | 
 | //sys	Setdomainname(p []byte) (err error) | 
 | //sys	Sethostname(p []byte) (err error) | 
 | //sysnb	Setpgid(pid int, pgid int) (err error) | 
 | //sysnb	Setsid() (pid int, err error) | 
 | //sysnb	Settimeofday(tv *Timeval) (err error) | 
 |  | 
 | // issue 1435. | 
 | // On linux Setuid and Setgid only affects the current thread, not the process. | 
 | // This does not match what most callers expect so we must return an error | 
 | // here rather than letting the caller think that the call succeeded. | 
 |  | 
 | func Setuid(uid int) (err error) { | 
 | 	return EOPNOTSUPP | 
 | } | 
 |  | 
 | func Setgid(gid int) (err error) { | 
 | 	return EOPNOTSUPP | 
 | } | 
 |  | 
 | //sys	Setpriority(which int, who int, prio int) (err error) | 
 | //sys	Setxattr(path string, attr string, data []byte, flags int) (err error) | 
 | //sys	Sync() | 
 | //sysnb	Sysinfo(info *Sysinfo_t) (err error) | 
 | //sys	Tee(rfd int, wfd int, len int, flags int) (n int64, err error) | 
 | //sysnb	Tgkill(tgid int, tid int, sig Signal) (err error) | 
 | //sysnb	Times(tms *Tms) (ticks uintptr, err error) | 
 | //sysnb	Umask(mask int) (oldmask int) | 
 | //sysnb	Uname(buf *Utsname) (err error) | 
 | //sys	Unmount(target string, flags int) (err error) = SYS_UMOUNT2 | 
 | //sys	Unshare(flags int) (err error) | 
 | //sys	Ustat(dev int, ubuf *Ustat_t) (err error) | 
 | //sys	Utime(path string, buf *Utimbuf) (err error) | 
 | //sys	write(fd int, p []byte) (n int, err error) | 
 | //sys	exitThread(code int) (err error) = SYS_EXIT | 
 | //sys	readlen(fd int, p *byte, np int) (n int, err error) = SYS_READ | 
 | //sys	writelen(fd int, p *byte, np int) (n int, err error) = SYS_WRITE | 
 |  | 
 | // mmap varies by architecture; see syscall_linux_*.go. | 
 | //sys	munmap(addr uintptr, length uintptr) (err error) | 
 |  | 
 | var mapper = &mmapper{ | 
 | 	active: make(map[*byte][]byte), | 
 | 	mmap:   mmap, | 
 | 	munmap: munmap, | 
 | } | 
 |  | 
 | func Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) { | 
 | 	return mapper.Mmap(fd, offset, length, prot, flags) | 
 | } | 
 |  | 
 | func Munmap(b []byte) (err error) { | 
 | 	return mapper.Munmap(b) | 
 | } | 
 |  | 
 | //sys	Madvise(b []byte, advice int) (err error) | 
 | //sys	Mprotect(b []byte, prot int) (err error) | 
 | //sys	Mlock(b []byte) (err error) | 
 | //sys	Munlock(b []byte) (err error) | 
 | //sys	Mlockall(flags int) (err error) | 
 | //sys	Munlockall() (err error) |