podman

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// Copyright 2011 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// Plan 9 system calls.
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// This file is compiled as ordinary Go code,
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// but it is also input to mksyscall,
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// which parses the //sys lines and generates system call stubs.
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// Note that sometimes we use a lowercase //sys name and
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// wrap it in our own nicer implementation.
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package plan9
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import (
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	"bytes"
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	"syscall"
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	"unsafe"
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)
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// A Note is a string describing a process note.
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// It implements the os.Signal interface.
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type Note string
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func (n Note) Signal() {}
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func (n Note) String() string {
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	return string(n)
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}
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var (
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	Stdin  = 0
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	Stdout = 1
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	Stderr = 2
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)
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// For testing: clients can set this flag to force
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// creation of IPv6 sockets to return EAFNOSUPPORT.
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var SocketDisableIPv6 bool
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func Syscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err syscall.ErrorString)
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func Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err syscall.ErrorString)
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func RawSyscall(trap, a1, a2, a3 uintptr) (r1, r2, err uintptr)
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func RawSyscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2, err uintptr)
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func atoi(b []byte) (n uint) {
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	n = 0
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	for i := 0; i < len(b); i++ {
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		n = n*10 + uint(b[i]-'0')
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	}
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	return
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}
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func cstring(s []byte) string {
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	i := bytes.IndexByte(s, 0)
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	if i == -1 {
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		i = len(s)
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	}
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	return string(s[:i])
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}
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func errstr() string {
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	var buf [ERRMAX]byte
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	RawSyscall(SYS_ERRSTR, uintptr(unsafe.Pointer(&buf[0])), uintptr(len(buf)), 0)
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	buf[len(buf)-1] = 0
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	return cstring(buf[:])
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}
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// Implemented in assembly to import from runtime.
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func exit(code int)
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func Exit(code int) { exit(code) }
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func readnum(path string) (uint, error) {
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	var b [12]byte
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	fd, e := Open(path, O_RDONLY)
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	if e != nil {
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		return 0, e
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	}
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	defer Close(fd)
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	n, e := Pread(fd, b[:], 0)
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	if e != nil {
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		return 0, e
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	}
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	m := 0
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	for ; m < n && b[m] == ' '; m++ {
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	}
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	return atoi(b[m : n-1]), nil
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}
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func Getpid() (pid int) {
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	n, _ := readnum("#c/pid")
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	return int(n)
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}
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func Getppid() (ppid int) {
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	n, _ := readnum("#c/ppid")
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	return int(n)
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}
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func Read(fd int, p []byte) (n int, err error) {
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	return Pread(fd, p, -1)
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}
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func Write(fd int, p []byte) (n int, err error) {
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	return Pwrite(fd, p, -1)
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}
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var ioSync int64
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//sys	fd2path(fd int, buf []byte) (err error)
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func Fd2path(fd int) (path string, err error) {
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	var buf [512]byte
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	e := fd2path(fd, buf[:])
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	if e != nil {
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		return "", e
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	}
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	return cstring(buf[:]), nil
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}
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//sys	pipe(p *[2]int32) (err error)
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func Pipe(p []int) (err error) {
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	if len(p) != 2 {
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		return syscall.ErrorString("bad arg in system call")
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	}
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	var pp [2]int32
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	err = pipe(&pp)
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	if err == nil {
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		p[0] = int(pp[0])
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		p[1] = int(pp[1])
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	}
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	return
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}
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// Underlying system call writes to newoffset via pointer.
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// Implemented in assembly to avoid allocation.
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func seek(placeholder uintptr, fd int, offset int64, whence int) (newoffset int64, err string)
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func Seek(fd int, offset int64, whence int) (newoffset int64, err error) {
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	newoffset, e := seek(0, fd, offset, whence)
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	if newoffset == -1 {
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		err = syscall.ErrorString(e)
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	}
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	return
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}
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func Mkdir(path string, mode uint32) (err error) {
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	fd, err := Create(path, O_RDONLY, DMDIR|mode)
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	if fd != -1 {
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		Close(fd)
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	}
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	return
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}
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type Waitmsg struct {
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	Pid  int
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	Time [3]uint32
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	Msg  string
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}
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func (w Waitmsg) Exited() bool   { return true }
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func (w Waitmsg) Signaled() bool { return false }
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func (w Waitmsg) ExitStatus() int {
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	if len(w.Msg) == 0 {
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		// a normal exit returns no message
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		return 0
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	}
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	return 1
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}
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//sys	await(s []byte) (n int, err error)
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func Await(w *Waitmsg) (err error) {
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	var buf [512]byte
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	var f [5][]byte
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	n, err := await(buf[:])
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	if err != nil || w == nil {
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		return
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	}
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	nf := 0
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	p := 0
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	for i := 0; i < n && nf < len(f)-1; i++ {
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		if buf[i] == ' ' {
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			f[nf] = buf[p:i]
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			p = i + 1
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			nf++
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		}
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	}
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	f[nf] = buf[p:]
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	nf++
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	if nf != len(f) {
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		return syscall.ErrorString("invalid wait message")
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	}
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	w.Pid = int(atoi(f[0]))
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	w.Time[0] = uint32(atoi(f[1]))
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	w.Time[1] = uint32(atoi(f[2]))
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	w.Time[2] = uint32(atoi(f[3]))
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	w.Msg = cstring(f[4])
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	if w.Msg == "''" {
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		// await() returns '' for no error
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		w.Msg = ""
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	}
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	return
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}
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func Unmount(name, old string) (err error) {
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	fixwd()
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	oldp, err := BytePtrFromString(old)
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	if err != nil {
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		return err
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	}
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	oldptr := uintptr(unsafe.Pointer(oldp))
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	var r0 uintptr
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	var e syscall.ErrorString
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	// bind(2) man page: If name is zero, everything bound or mounted upon old is unbound or unmounted.
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	if name == "" {
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		r0, _, e = Syscall(SYS_UNMOUNT, _zero, oldptr, 0)
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	} else {
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		namep, err := BytePtrFromString(name)
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		if err != nil {
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			return err
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		}
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		r0, _, e = Syscall(SYS_UNMOUNT, uintptr(unsafe.Pointer(namep)), oldptr, 0)
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	}
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	if int32(r0) == -1 {
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		err = e
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	}
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	return
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}
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func Fchdir(fd int) (err error) {
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	path, err := Fd2path(fd)
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	if err != nil {
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		return
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	}
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	return Chdir(path)
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}
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type Timespec struct {
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	Sec  int32
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	Nsec int32
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}
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type Timeval struct {
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	Sec  int32
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	Usec int32
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}
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func NsecToTimeval(nsec int64) (tv Timeval) {
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	nsec += 999 // round up to microsecond
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	tv.Usec = int32(nsec % 1e9 / 1e3)
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	tv.Sec = int32(nsec / 1e9)
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	return
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}
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func nsec() int64 {
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	var scratch int64
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	r0, _, _ := Syscall(SYS_NSEC, uintptr(unsafe.Pointer(&scratch)), 0, 0)
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	// TODO(aram): remove hack after I fix _nsec in the pc64 kernel.
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	if r0 == 0 {
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		return scratch
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	}
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	return int64(r0)
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}
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func Gettimeofday(tv *Timeval) error {
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	nsec := nsec()
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	*tv = NsecToTimeval(nsec)
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	return nil
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}
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func Getpagesize() int { return 0x1000 }
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func Getegid() (egid int) { return -1 }
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func Geteuid() (euid int) { return -1 }
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func Getgid() (gid int)   { return -1 }
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func Getuid() (uid int)   { return -1 }
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func Getgroups() (gids []int, err error) {
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	return make([]int, 0), nil
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}
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//sys	open(path string, mode int) (fd int, err error)
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func Open(path string, mode int) (fd int, err error) {
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	fixwd()
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	return open(path, mode)
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}
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//sys	create(path string, mode int, perm uint32) (fd int, err error)
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func Create(path string, mode int, perm uint32) (fd int, err error) {
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	fixwd()
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	return create(path, mode, perm)
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}
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//sys	remove(path string) (err error)
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func Remove(path string) error {
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	fixwd()
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	return remove(path)
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}
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//sys	stat(path string, edir []byte) (n int, err error)
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func Stat(path string, edir []byte) (n int, err error) {
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	fixwd()
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	return stat(path, edir)
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}
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//sys	bind(name string, old string, flag int) (err error)
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func Bind(name string, old string, flag int) (err error) {
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	fixwd()
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	return bind(name, old, flag)
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}
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//sys	mount(fd int, afd int, old string, flag int, aname string) (err error)
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func Mount(fd int, afd int, old string, flag int, aname string) (err error) {
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	fixwd()
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	return mount(fd, afd, old, flag, aname)
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}
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//sys	wstat(path string, edir []byte) (err error)
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func Wstat(path string, edir []byte) (err error) {
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	fixwd()
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	return wstat(path, edir)
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}
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//sys	chdir(path string) (err error)
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//sys	Dup(oldfd int, newfd int) (fd int, err error)
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//sys	Pread(fd int, p []byte, offset int64) (n int, err error)
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//sys	Pwrite(fd int, p []byte, offset int64) (n int, err error)
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//sys	Close(fd int) (err error)
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//sys	Fstat(fd int, edir []byte) (n int, err error)
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//sys	Fwstat(fd int, edir []byte) (err error)
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