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.
5 // +build darwin freebsd linux netbsd openbsd windows
14 func sigpipe() // implemented in package runtime
16 // Link creates newname as a hard link to the oldname file.
17 // If there is an error, it will be of type *LinkError.
18 func Link(oldname, newname string) error {
19 e := syscall.Link(oldname, newname)
21 return &LinkError{"link", oldname, newname, e}
26 // Symlink creates newname as a symbolic link to oldname.
27 // If there is an error, it will be of type *LinkError.
28 func Symlink(oldname, newname string) error {
29 e := syscall.Symlink(oldname, newname)
31 return &LinkError{"symlink", oldname, newname, e}
36 // Readlink returns the destination of the named symbolic link.
37 // If there is an error, it will be of type *PathError.
38 func Readlink(name string) (string, error) {
39 for len := 128; ; len *= 2 {
40 b := make([]byte, len)
41 n, e := syscall.Readlink(name, b)
43 return "", &PathError{"readlink", name, e}
46 return string(b[0:n]), nil
53 // Rename renames a file.
54 func Rename(oldname, newname string) error {
55 e := syscall.Rename(oldname, newname)
57 return &LinkError{"rename", oldname, newname, e}
62 // syscallMode returns the syscall-specific mode bits from Go's portable mode bits.
63 func syscallMode(i FileMode) (o uint32) {
65 if i&ModeSetuid != 0 {
68 if i&ModeSetgid != 0 {
71 if i&ModeSticky != 0 {
74 // No mapping for Go's ModeTemporary (plan9 only).
78 // Chmod changes the mode of the named file to mode.
79 // If the file is a symbolic link, it changes the mode of the link's target.
80 // If there is an error, it will be of type *PathError.
81 func Chmod(name string, mode FileMode) error {
82 if e := syscall.Chmod(name, syscallMode(mode)); e != nil {
83 return &PathError{"chmod", name, e}
88 // Chmod changes the mode of the file to mode.
89 // If there is an error, it will be of type *PathError.
90 func (f *File) Chmod(mode FileMode) error {
91 if e := syscall.Fchmod(f.fd, syscallMode(mode)); e != nil {
92 return &PathError{"chmod", f.name, e}
97 // Chown changes the numeric uid and gid of the named file.
98 // If the file is a symbolic link, it changes the uid and gid of the link's target.
99 // If there is an error, it will be of type *PathError.
100 func Chown(name string, uid, gid int) error {
101 if e := syscall.Chown(name, uid, gid); e != nil {
102 return &PathError{"chown", name, e}
107 // Lchown changes the numeric uid and gid of the named file.
108 // If the file is a symbolic link, it changes the uid and gid of the link itself.
109 // If there is an error, it will be of type *PathError.
110 func Lchown(name string, uid, gid int) error {
111 if e := syscall.Lchown(name, uid, gid); e != nil {
112 return &PathError{"lchown", name, e}
117 // Chown changes the numeric uid and gid of the named file.
118 // If there is an error, it will be of type *PathError.
119 func (f *File) Chown(uid, gid int) error {
120 if e := syscall.Fchown(f.fd, uid, gid); e != nil {
121 return &PathError{"chown", f.name, e}
126 // Truncate changes the size of the file.
127 // It does not change the I/O offset.
128 // If there is an error, it will be of type *PathError.
129 func (f *File) Truncate(size int64) error {
130 if e := syscall.Ftruncate(f.fd, size); e != nil {
131 return &PathError{"truncate", f.name, e}
136 // Sync commits the current contents of the file to stable storage.
137 // Typically, this means flushing the file system's in-memory copy
138 // of recently written data to disk.
139 func (f *File) Sync() (err error) {
141 return syscall.EINVAL
143 if e := syscall.Fsync(f.fd); e != nil {
144 return NewSyscallError("fsync", e)
149 // Chtimes changes the access and modification times of the named
150 // file, similar to the Unix utime() or utimes() functions.
152 // The underlying filesystem may truncate or round the values to a
153 // less precise time unit.
154 // If there is an error, it will be of type *PathError.
155 func Chtimes(name string, atime time.Time, mtime time.Time) error {
156 var utimes [2]syscall.Timeval
157 atime_ns := atime.Unix()*1e9 + int64(atime.Nanosecond())
158 mtime_ns := mtime.Unix()*1e9 + int64(mtime.Nanosecond())
159 utimes[0] = syscall.NsecToTimeval(atime_ns)
160 utimes[1] = syscall.NsecToTimeval(mtime_ns)
161 if e := syscall.Utimes(name, utimes[0:]); e != nil {
162 return &PathError{"chtimes", name, e}