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Source file src/syscall/syscall_bsd.go

Documentation: syscall

		 1  // Copyright 2009 The Go Authors. All rights reserved.
		 2  // Use of this source code is governed by a BSD-style
		 3  // license that can be found in the LICENSE file.
		 4  
		 5  //go:build darwin || dragonfly || freebsd || netbsd || openbsd
		 6  // +build darwin dragonfly freebsd netbsd openbsd
		 7  
		 8  // BSD system call wrappers shared by *BSD based systems
		 9  // including OS X (Darwin) and FreeBSD.	Like the other
		10  // syscall_*.go files it is compiled as Go code but also
		11  // used as input to mksyscall which parses the //sys
		12  // lines and generates system call stubs.
		13  
		14  package syscall
		15  
		16  import (
		17  	"runtime"
		18  	"unsafe"
		19  )
		20  
		21  const ImplementsGetwd = true
		22  
		23  func Getwd() (string, error) {
		24  	var buf [pathMax]byte
		25  	_, err := getcwd(buf[:])
		26  	if err != nil {
		27  		return "", err
		28  	}
		29  	n := clen(buf[:])
		30  	if n < 1 {
		31  		return "", EINVAL
		32  	}
		33  	return string(buf[:n]), nil
		34  }
		35  
		36  /*
		37   * Wrapped
		38   */
		39  
		40  //sysnb	getgroups(ngid int, gid *_Gid_t) (n int, err error)
		41  //sysnb	setgroups(ngid int, gid *_Gid_t) (err error)
		42  
		43  func Getgroups() (gids []int, err error) {
		44  	n, err := getgroups(0, nil)
		45  	if err != nil {
		46  		return nil, err
		47  	}
		48  	if n == 0 {
		49  		return nil, nil
		50  	}
		51  
		52  	// Sanity check group count. Max is 16 on BSD.
		53  	if n < 0 || n > 1000 {
		54  		return nil, EINVAL
		55  	}
		56  
		57  	a := make([]_Gid_t, n)
		58  	n, err = getgroups(n, &a[0])
		59  	if err != nil {
		60  		return nil, err
		61  	}
		62  	gids = make([]int, n)
		63  	for i, v := range a[0:n] {
		64  		gids[i] = int(v)
		65  	}
		66  	return
		67  }
		68  
		69  func Setgroups(gids []int) (err error) {
		70  	if len(gids) == 0 {
		71  		return setgroups(0, nil)
		72  	}
		73  
		74  	a := make([]_Gid_t, len(gids))
		75  	for i, v := range gids {
		76  		a[i] = _Gid_t(v)
		77  	}
		78  	return setgroups(len(a), &a[0])
		79  }
		80  
		81  func ReadDirent(fd int, buf []byte) (n int, err error) {
		82  	// Final argument is (basep *uintptr) and the syscall doesn't take nil.
		83  	// 64 bits should be enough. (32 bits isn't even on 386). Since the
		84  	// actual system call is getdirentries64, 64 is a good guess.
		85  	// TODO(rsc): Can we use a single global basep for all calls?
		86  	var base = (*uintptr)(unsafe.Pointer(new(uint64)))
		87  	return Getdirentries(fd, buf, base)
		88  }
		89  
		90  // Wait status is 7 bits at bottom, either 0 (exited),
		91  // 0x7F (stopped), or a signal number that caused an exit.
		92  // The 0x80 bit is whether there was a core dump.
		93  // An extra number (exit code, signal causing a stop)
		94  // is in the high bits.
		95  
		96  type WaitStatus uint32
		97  
		98  const (
		99  	mask	= 0x7F
	 100  	core	= 0x80
	 101  	shift = 8
	 102  
	 103  	exited	= 0
	 104  	stopped = 0x7F
	 105  )
	 106  
	 107  func (w WaitStatus) Exited() bool { return w&mask == exited }
	 108  
	 109  func (w WaitStatus) ExitStatus() int {
	 110  	if w&mask != exited {
	 111  		return -1
	 112  	}
	 113  	return int(w >> shift)
	 114  }
	 115  
	 116  func (w WaitStatus) Signaled() bool { return w&mask != stopped && w&mask != 0 }
	 117  
	 118  func (w WaitStatus) Signal() Signal {
	 119  	sig := Signal(w & mask)
	 120  	if sig == stopped || sig == 0 {
	 121  		return -1
	 122  	}
	 123  	return sig
	 124  }
	 125  
	 126  func (w WaitStatus) CoreDump() bool { return w.Signaled() && w&core != 0 }
	 127  
	 128  func (w WaitStatus) Stopped() bool { return w&mask == stopped && Signal(w>>shift) != SIGSTOP }
	 129  
	 130  func (w WaitStatus) Continued() bool { return w&mask == stopped && Signal(w>>shift) == SIGSTOP }
	 131  
	 132  func (w WaitStatus) StopSignal() Signal {
	 133  	if !w.Stopped() {
	 134  		return -1
	 135  	}
	 136  	return Signal(w>>shift) & 0xFF
	 137  }
	 138  
	 139  func (w WaitStatus) TrapCause() int { return -1 }
	 140  
	 141  //sys	wait4(pid int, wstatus *_C_int, options int, rusage *Rusage) (wpid int, err error)
	 142  
	 143  func Wait4(pid int, wstatus *WaitStatus, options int, rusage *Rusage) (wpid int, err error) {
	 144  	var status _C_int
	 145  	wpid, err = wait4(pid, &status, options, rusage)
	 146  	if wstatus != nil {
	 147  		*wstatus = WaitStatus(status)
	 148  	}
	 149  	return
	 150  }
	 151  
	 152  //sys	accept(s int, rsa *RawSockaddrAny, addrlen *_Socklen) (fd int, err error)
	 153  //sys	bind(s int, addr unsafe.Pointer, addrlen _Socklen) (err error)
	 154  //sys	connect(s int, addr unsafe.Pointer, addrlen _Socklen) (err error)
	 155  //sysnb	socket(domain int, typ int, proto int) (fd int, err error)
	 156  //sys	getsockopt(s int, level int, name int, val unsafe.Pointer, vallen *_Socklen) (err error)
	 157  //sys	setsockopt(s int, level int, name int, val unsafe.Pointer, vallen uintptr) (err error)
	 158  //sysnb	getpeername(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error)
	 159  //sysnb	getsockname(fd int, rsa *RawSockaddrAny, addrlen *_Socklen) (err error)
	 160  //sys	Shutdown(s int, how int) (err error)
	 161  
	 162  func (sa *SockaddrInet4) sockaddr() (unsafe.Pointer, _Socklen, error) {
	 163  	if sa.Port < 0 || sa.Port > 0xFFFF {
	 164  		return nil, 0, EINVAL
	 165  	}
	 166  	sa.raw.Len = SizeofSockaddrInet4
	 167  	sa.raw.Family = AF_INET
	 168  	p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port))
	 169  	p[0] = byte(sa.Port >> 8)
	 170  	p[1] = byte(sa.Port)
	 171  	for i := 0; i < len(sa.Addr); i++ {
	 172  		sa.raw.Addr[i] = sa.Addr[i]
	 173  	}
	 174  	return unsafe.Pointer(&sa.raw), _Socklen(sa.raw.Len), nil
	 175  }
	 176  
	 177  func (sa *SockaddrInet6) sockaddr() (unsafe.Pointer, _Socklen, error) {
	 178  	if sa.Port < 0 || sa.Port > 0xFFFF {
	 179  		return nil, 0, EINVAL
	 180  	}
	 181  	sa.raw.Len = SizeofSockaddrInet6
	 182  	sa.raw.Family = AF_INET6
	 183  	p := (*[2]byte)(unsafe.Pointer(&sa.raw.Port))
	 184  	p[0] = byte(sa.Port >> 8)
	 185  	p[1] = byte(sa.Port)
	 186  	sa.raw.Scope_id = sa.ZoneId
	 187  	for i := 0; i < len(sa.Addr); i++ {
	 188  		sa.raw.Addr[i] = sa.Addr[i]
	 189  	}
	 190  	return unsafe.Pointer(&sa.raw), _Socklen(sa.raw.Len), nil
	 191  }
	 192  
	 193  func (sa *SockaddrUnix) sockaddr() (unsafe.Pointer, _Socklen, error) {
	 194  	name := sa.Name
	 195  	n := len(name)
	 196  	if n >= len(sa.raw.Path) || n == 0 {
	 197  		return nil, 0, EINVAL
	 198  	}
	 199  	sa.raw.Len = byte(3 + n) // 2 for Family, Len; 1 for NUL
	 200  	sa.raw.Family = AF_UNIX
	 201  	for i := 0; i < n; i++ {
	 202  		sa.raw.Path[i] = int8(name[i])
	 203  	}
	 204  	return unsafe.Pointer(&sa.raw), _Socklen(sa.raw.Len), nil
	 205  }
	 206  
	 207  func (sa *SockaddrDatalink) sockaddr() (unsafe.Pointer, _Socklen, error) {
	 208  	if sa.Index == 0 {
	 209  		return nil, 0, EINVAL
	 210  	}
	 211  	sa.raw.Len = sa.Len
	 212  	sa.raw.Family = AF_LINK
	 213  	sa.raw.Index = sa.Index
	 214  	sa.raw.Type = sa.Type
	 215  	sa.raw.Nlen = sa.Nlen
	 216  	sa.raw.Alen = sa.Alen
	 217  	sa.raw.Slen = sa.Slen
	 218  	for i := 0; i < len(sa.raw.Data); i++ {
	 219  		sa.raw.Data[i] = sa.Data[i]
	 220  	}
	 221  	return unsafe.Pointer(&sa.raw), SizeofSockaddrDatalink, nil
	 222  }
	 223  
	 224  func anyToSockaddr(rsa *RawSockaddrAny) (Sockaddr, error) {
	 225  	switch rsa.Addr.Family {
	 226  	case AF_LINK:
	 227  		pp := (*RawSockaddrDatalink)(unsafe.Pointer(rsa))
	 228  		sa := new(SockaddrDatalink)
	 229  		sa.Len = pp.Len
	 230  		sa.Family = pp.Family
	 231  		sa.Index = pp.Index
	 232  		sa.Type = pp.Type
	 233  		sa.Nlen = pp.Nlen
	 234  		sa.Alen = pp.Alen
	 235  		sa.Slen = pp.Slen
	 236  		for i := 0; i < len(sa.Data); i++ {
	 237  			sa.Data[i] = pp.Data[i]
	 238  		}
	 239  		return sa, nil
	 240  
	 241  	case AF_UNIX:
	 242  		pp := (*RawSockaddrUnix)(unsafe.Pointer(rsa))
	 243  		if pp.Len < 2 || pp.Len > SizeofSockaddrUnix {
	 244  			return nil, EINVAL
	 245  		}
	 246  		sa := new(SockaddrUnix)
	 247  
	 248  		// Some BSDs include the trailing NUL in the length, whereas
	 249  		// others do not. Work around this by subtracting the leading
	 250  		// family and len. The path is then scanned to see if a NUL
	 251  		// terminator still exists within the length.
	 252  		n := int(pp.Len) - 2 // subtract leading Family, Len
	 253  		for i := 0; i < n; i++ {
	 254  			if pp.Path[i] == 0 {
	 255  				// found early NUL; assume Len included the NUL
	 256  				// or was overestimating.
	 257  				n = i
	 258  				break
	 259  			}
	 260  		}
	 261  		bytes := (*[len(pp.Path)]byte)(unsafe.Pointer(&pp.Path[0]))[0:n]
	 262  		sa.Name = string(bytes)
	 263  		return sa, nil
	 264  
	 265  	case AF_INET:
	 266  		pp := (*RawSockaddrInet4)(unsafe.Pointer(rsa))
	 267  		sa := new(SockaddrInet4)
	 268  		p := (*[2]byte)(unsafe.Pointer(&pp.Port))
	 269  		sa.Port = int(p[0])<<8 + int(p[1])
	 270  		for i := 0; i < len(sa.Addr); i++ {
	 271  			sa.Addr[i] = pp.Addr[i]
	 272  		}
	 273  		return sa, nil
	 274  
	 275  	case AF_INET6:
	 276  		pp := (*RawSockaddrInet6)(unsafe.Pointer(rsa))
	 277  		sa := new(SockaddrInet6)
	 278  		p := (*[2]byte)(unsafe.Pointer(&pp.Port))
	 279  		sa.Port = int(p[0])<<8 + int(p[1])
	 280  		sa.ZoneId = pp.Scope_id
	 281  		for i := 0; i < len(sa.Addr); i++ {
	 282  			sa.Addr[i] = pp.Addr[i]
	 283  		}
	 284  		return sa, nil
	 285  	}
	 286  	return nil, EAFNOSUPPORT
	 287  }
	 288  
	 289  func Accept(fd int) (nfd int, sa Sockaddr, err error) {
	 290  	var rsa RawSockaddrAny
	 291  	var len _Socklen = SizeofSockaddrAny
	 292  	nfd, err = accept(fd, &rsa, &len)
	 293  	if err != nil {
	 294  		return
	 295  	}
	 296  	if (runtime.GOOS == "darwin" || runtime.GOOS == "ios") && len == 0 {
	 297  		// Accepted socket has no address.
	 298  		// This is likely due to a bug in xnu kernels,
	 299  		// where instead of ECONNABORTED error socket
	 300  		// is accepted, but has no address.
	 301  		Close(nfd)
	 302  		return 0, nil, ECONNABORTED
	 303  	}
	 304  	sa, err = anyToSockaddr(&rsa)
	 305  	if err != nil {
	 306  		Close(nfd)
	 307  		nfd = 0
	 308  	}
	 309  	return
	 310  }
	 311  
	 312  func Getsockname(fd int) (sa Sockaddr, err error) {
	 313  	var rsa RawSockaddrAny
	 314  	var len _Socklen = SizeofSockaddrAny
	 315  	if err = getsockname(fd, &rsa, &len); err != nil {
	 316  		return
	 317  	}
	 318  	// TODO(jsing): DragonFly has a "bug" (see issue 3349), which should be
	 319  	// reported upstream.
	 320  	if runtime.GOOS == "dragonfly" && rsa.Addr.Family == AF_UNSPEC && rsa.Addr.Len == 0 {
	 321  		rsa.Addr.Family = AF_UNIX
	 322  		rsa.Addr.Len = SizeofSockaddrUnix
	 323  	}
	 324  	return anyToSockaddr(&rsa)
	 325  }
	 326  
	 327  //sysnb socketpair(domain int, typ int, proto int, fd *[2]int32) (err error)
	 328  
	 329  func GetsockoptByte(fd, level, opt int) (value byte, err error) {
	 330  	var n byte
	 331  	vallen := _Socklen(1)
	 332  	err = getsockopt(fd, level, opt, unsafe.Pointer(&n), &vallen)
	 333  	return n, err
	 334  }
	 335  
	 336  func GetsockoptInet4Addr(fd, level, opt int) (value [4]byte, err error) {
	 337  	vallen := _Socklen(4)
	 338  	err = getsockopt(fd, level, opt, unsafe.Pointer(&value[0]), &vallen)
	 339  	return value, err
	 340  }
	 341  
	 342  func GetsockoptIPMreq(fd, level, opt int) (*IPMreq, error) {
	 343  	var value IPMreq
	 344  	vallen := _Socklen(SizeofIPMreq)
	 345  	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
	 346  	return &value, err
	 347  }
	 348  
	 349  func GetsockoptIPv6Mreq(fd, level, opt int) (*IPv6Mreq, error) {
	 350  	var value IPv6Mreq
	 351  	vallen := _Socklen(SizeofIPv6Mreq)
	 352  	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
	 353  	return &value, err
	 354  }
	 355  
	 356  func GetsockoptIPv6MTUInfo(fd, level, opt int) (*IPv6MTUInfo, error) {
	 357  	var value IPv6MTUInfo
	 358  	vallen := _Socklen(SizeofIPv6MTUInfo)
	 359  	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
	 360  	return &value, err
	 361  }
	 362  
	 363  func GetsockoptICMPv6Filter(fd, level, opt int) (*ICMPv6Filter, error) {
	 364  	var value ICMPv6Filter
	 365  	vallen := _Socklen(SizeofICMPv6Filter)
	 366  	err := getsockopt(fd, level, opt, unsafe.Pointer(&value), &vallen)
	 367  	return &value, err
	 368  }
	 369  
	 370  //sys	 recvfrom(fd int, p []byte, flags int, from *RawSockaddrAny, fromlen *_Socklen) (n int, err error)
	 371  //sys	 sendto(s int, buf []byte, flags int, to unsafe.Pointer, addrlen _Socklen) (err error)
	 372  //sys	recvmsg(s int, msg *Msghdr, flags int) (n int, err error)
	 373  
	 374  func Recvmsg(fd int, p, oob []byte, flags int) (n, oobn int, recvflags int, from Sockaddr, err error) {
	 375  	var msg Msghdr
	 376  	var rsa RawSockaddrAny
	 377  	msg.Name = (*byte)(unsafe.Pointer(&rsa))
	 378  	msg.Namelen = uint32(SizeofSockaddrAny)
	 379  	var iov Iovec
	 380  	if len(p) > 0 {
	 381  		iov.Base = (*byte)(unsafe.Pointer(&p[0]))
	 382  		iov.SetLen(len(p))
	 383  	}
	 384  	var dummy byte
	 385  	if len(oob) > 0 {
	 386  		// receive at least one normal byte
	 387  		if len(p) == 0 {
	 388  			iov.Base = &dummy
	 389  			iov.SetLen(1)
	 390  		}
	 391  		msg.Control = (*byte)(unsafe.Pointer(&oob[0]))
	 392  		msg.SetControllen(len(oob))
	 393  	}
	 394  	msg.Iov = &iov
	 395  	msg.Iovlen = 1
	 396  	if n, err = recvmsg(fd, &msg, flags); err != nil {
	 397  		return
	 398  	}
	 399  	oobn = int(msg.Controllen)
	 400  	recvflags = int(msg.Flags)
	 401  	// source address is only specified if the socket is unconnected
	 402  	if rsa.Addr.Family != AF_UNSPEC {
	 403  		from, err = anyToSockaddr(&rsa)
	 404  	}
	 405  	return
	 406  }
	 407  
	 408  //sys	sendmsg(s int, msg *Msghdr, flags int) (n int, err error)
	 409  
	 410  func Sendmsg(fd int, p, oob []byte, to Sockaddr, flags int) (err error) {
	 411  	_, err = SendmsgN(fd, p, oob, to, flags)
	 412  	return
	 413  }
	 414  
	 415  func SendmsgN(fd int, p, oob []byte, to Sockaddr, flags int) (n int, err error) {
	 416  	var ptr unsafe.Pointer
	 417  	var salen _Socklen
	 418  	if to != nil {
	 419  		ptr, salen, err = to.sockaddr()
	 420  		if err != nil {
	 421  			return 0, err
	 422  		}
	 423  	}
	 424  	var msg Msghdr
	 425  	msg.Name = (*byte)(unsafe.Pointer(ptr))
	 426  	msg.Namelen = uint32(salen)
	 427  	var iov Iovec
	 428  	if len(p) > 0 {
	 429  		iov.Base = (*byte)(unsafe.Pointer(&p[0]))
	 430  		iov.SetLen(len(p))
	 431  	}
	 432  	var dummy byte
	 433  	if len(oob) > 0 {
	 434  		// send at least one normal byte
	 435  		if len(p) == 0 {
	 436  			iov.Base = &dummy
	 437  			iov.SetLen(1)
	 438  		}
	 439  		msg.Control = (*byte)(unsafe.Pointer(&oob[0]))
	 440  		msg.SetControllen(len(oob))
	 441  	}
	 442  	msg.Iov = &iov
	 443  	msg.Iovlen = 1
	 444  	if n, err = sendmsg(fd, &msg, flags); err != nil {
	 445  		return 0, err
	 446  	}
	 447  	if len(oob) > 0 && len(p) == 0 {
	 448  		n = 0
	 449  	}
	 450  	return n, nil
	 451  }
	 452  
	 453  //sys	kevent(kq int, change unsafe.Pointer, nchange int, event unsafe.Pointer, nevent int, timeout *Timespec) (n int, err error)
	 454  
	 455  func Kevent(kq int, changes, events []Kevent_t, timeout *Timespec) (n int, err error) {
	 456  	var change, event unsafe.Pointer
	 457  	if len(changes) > 0 {
	 458  		change = unsafe.Pointer(&changes[0])
	 459  	}
	 460  	if len(events) > 0 {
	 461  		event = unsafe.Pointer(&events[0])
	 462  	}
	 463  	return kevent(kq, change, len(changes), event, len(events), timeout)
	 464  }
	 465  
	 466  func Sysctl(name string) (value string, err error) {
	 467  	// Translate name to mib number.
	 468  	mib, err := nametomib(name)
	 469  	if err != nil {
	 470  		return "", err
	 471  	}
	 472  
	 473  	// Find size.
	 474  	n := uintptr(0)
	 475  	if err = sysctl(mib, nil, &n, nil, 0); err != nil {
	 476  		return "", err
	 477  	}
	 478  	if n == 0 {
	 479  		return "", nil
	 480  	}
	 481  
	 482  	// Read into buffer of that size.
	 483  	buf := make([]byte, n)
	 484  	if err = sysctl(mib, &buf[0], &n, nil, 0); err != nil {
	 485  		return "", err
	 486  	}
	 487  
	 488  	// Throw away terminating NUL.
	 489  	if n > 0 && buf[n-1] == '\x00' {
	 490  		n--
	 491  	}
	 492  	return string(buf[0:n]), nil
	 493  }
	 494  
	 495  func SysctlUint32(name string) (value uint32, err error) {
	 496  	// Translate name to mib number.
	 497  	mib, err := nametomib(name)
	 498  	if err != nil {
	 499  		return 0, err
	 500  	}
	 501  
	 502  	// Read into buffer of that size.
	 503  	n := uintptr(4)
	 504  	buf := make([]byte, 4)
	 505  	if err = sysctl(mib, &buf[0], &n, nil, 0); err != nil {
	 506  		return 0, err
	 507  	}
	 508  	if n != 4 {
	 509  		return 0, EIO
	 510  	}
	 511  	return *(*uint32)(unsafe.Pointer(&buf[0])), nil
	 512  }
	 513  
	 514  //sys	utimes(path string, timeval *[2]Timeval) (err error)
	 515  
	 516  func Utimes(path string, tv []Timeval) (err error) {
	 517  	if len(tv) != 2 {
	 518  		return EINVAL
	 519  	}
	 520  	return utimes(path, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
	 521  }
	 522  
	 523  func UtimesNano(path string, ts []Timespec) error {
	 524  	if len(ts) != 2 {
	 525  		return EINVAL
	 526  	}
	 527  	// Darwin setattrlist can set nanosecond timestamps
	 528  	err := setattrlistTimes(path, ts)
	 529  	if err != ENOSYS {
	 530  		return err
	 531  	}
	 532  	err = utimensat(_AT_FDCWD, path, (*[2]Timespec)(unsafe.Pointer(&ts[0])), 0)
	 533  	if err != ENOSYS {
	 534  		return err
	 535  	}
	 536  	// Not as efficient as it could be because Timespec and
	 537  	// Timeval have different types in the different OSes
	 538  	tv := [2]Timeval{
	 539  		NsecToTimeval(TimespecToNsec(ts[0])),
	 540  		NsecToTimeval(TimespecToNsec(ts[1])),
	 541  	}
	 542  	return utimes(path, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
	 543  }
	 544  
	 545  //sys	futimes(fd int, timeval *[2]Timeval) (err error)
	 546  
	 547  func Futimes(fd int, tv []Timeval) (err error) {
	 548  	if len(tv) != 2 {
	 549  		return EINVAL
	 550  	}
	 551  	return futimes(fd, (*[2]Timeval)(unsafe.Pointer(&tv[0])))
	 552  }
	 553  
	 554  //sys	fcntl(fd int, cmd int, arg int) (val int, err error)
	 555  
	 556  var mapper = &mmapper{
	 557  	active: make(map[*byte][]byte),
	 558  	mmap:	 mmap,
	 559  	munmap: munmap,
	 560  }
	 561  
	 562  func Mmap(fd int, offset int64, length int, prot int, flags int) (data []byte, err error) {
	 563  	return mapper.Mmap(fd, offset, length, prot, flags)
	 564  }
	 565  
	 566  func Munmap(b []byte) (err error) {
	 567  	return mapper.Munmap(b)
	 568  }
	 569  

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