-.\" Hey Emacs! This file is -*- nroff -*- source.
-.\"
.\" This manpage is Copyright (C) 1992 Drew Eckhardt;
-.\" 1993 Michael Haardt, Ian Jackson.
+.\" and Copyright (C) 1993 Michael Haardt, Ian Jackson.
+.\" and Copyright (C) 2006, 2014 Michael Kerrisk
.\"
+.\" %%%LICENSE_START(VERBATIM)
.\" Permission is granted to make and distribute verbatim copies of this
.\" manual provided the copyright notice and this permission notice are
.\" preserved on all copies.
.\"
.\" Formatted or processed versions of this manual, if unaccompanied by
.\" the source, must acknowledge the copyright and authors of this work.
+.\" %%%LICENSE_END
.\"
.\" Modified 1993-07-24 by Rik Faith
.\" Modified 1996-04-26 by Nick Duffek <nsd@bbc.com>
.\" Modified 1997-01-31 by Eric S. Raymond <esr@thyrsus.com>
.\" Modified 2004-06-23 by Michael Kerrisk <mtk.manpages@gmail.com>
.\"
-.TH SYMLINK 2 2007-07-26 "Linux" "Linux Programmer's Manual"
+.TH SYMLINK 2 2014-08-19 "Linux" "Linux Programmer's Manual"
.SH NAME
-symlink \- make a new name for a file
+symlink, symlinkat \- make a new name for a file
.SH SYNOPSIS
+.nf
+.B #include <unistd.h>
+.sp
+.BI "int symlink(const char *" target ", const char *" linkpath );
+.sp
+.BR "#include <fcntl.h> " "/* Definition of AT_* constants */"
.B #include <unistd.h>
.sp
-.BI "int symlink(const char *" oldpath ", const char *" newpath );
+.BI "int symlinkat(const char *" target ", int " newdirfd \
+", const char *" linkpath );
.sp
+.fi
.in -4n
Feature Test Macro Requirements for glibc (see
.BR feature_test_macros (7)):
.sp
.ad l
.BR symlink ():
-_BSD_SOURCE || _XOPEN_SOURCE\ >=\ 500 || _POSIX_C_SOURCE\ >=\ 200112L
+.RS 4
+_BSD_SOURCE || _XOPEN_SOURCE\ >=\ 500 ||
+_XOPEN_SOURCE\ &&\ _XOPEN_SOURCE_EXTENDED || _POSIX_C_SOURCE\ >=\ 200112L
+.RE
+.sp
+.BR symlinkat ():
+.PD 0
+.ad l
+.RS 4
+.TP 4
+Since glibc 2.10:
+_XOPEN_SOURCE\ >=\ 700 || _POSIX_C_SOURCE\ >=\ 200809L
+.TP
+Before glibc 2.10:
+_ATFILE_SOURCE
+.RE
.ad b
+.PD
.SH DESCRIPTION
.BR symlink ()
creates a symbolic link named
-.I newpath
+.I linkpath
which contains the string
-.IR oldpath .
+.IR target .
Symbolic links are interpreted at run time as if the contents of the
link had been substituted into the path being followed to find a file or
set.
If
-.I newpath
-exists it will
+.I linkpath
+exists, it will
.I not
be overwritten.
-.SH "RETURN VALUE"
+.SS symlinkat()
+The
+.BR symlinkat ()
+system call operates in exactly the same way as
+.BR symlink (),
+except for the differences described here.
+
+If the pathname given in
+.I linkpath
+is relative, then it is interpreted relative to the directory
+referred to by the file descriptor
+.I newdirfd
+(rather than relative to the current working directory of
+the calling process, as is done by
+.BR symlink ()
+for a relative pathname).
+
+If
+.I linkpath
+is relative and
+.I newdirfd
+is the special value
+.BR AT_FDCWD ,
+then
+.I linkpath
+is interpreted relative to the current working
+directory of the calling process (like
+.BR symlink ()).
+
+If
+.I linkpath
+is absolute, then
+.I newdirfd
+is ignored.
+.SH RETURN VALUE
On success, zero is returned.
On error, \-1 is returned, and
.I errno
.TP
.B EACCES
Write access to the directory containing
-.I newpath
+.I linkpath
is denied, or one of the directories in the path prefix of
-.I newpath
+.I linkpath
did not allow search permission.
(See also
.BR path_resolution (7).)
.TP
+.B EDQUOT
+The user's quota of resources on the filesystem has been exhausted.
+The resources could be inodes or disk blocks, depending on the filesystem
+implementation.
+.TP
.B EEXIST
-.I newpath
+.I linkpath
already exists.
.TP
.B EFAULT
-.IR oldpath " or " newpath " points outside your accessible address space."
+.IR target " or " linkpath " points outside your accessible address space."
.TP
.B EIO
An I/O error occurred.
.TP
.B ELOOP
Too many symbolic links were encountered in resolving
-.IR newpath .
+.IR linkpath .
.TP
.B ENAMETOOLONG
-.IR oldpath " or " newpath " was too long."
+.IR target " or " linkpath " was too long."
.TP
.B ENOENT
A directory component in
-.I newpath
+.I linkpath
does not exist or is a dangling symbolic link, or
-.I oldpath
+.I target
is the empty string.
.TP
.B ENOMEM
.TP
.B ENOTDIR
A component used as a directory in
-.I newpath
+.I linkpath
is not, in fact, a directory.
.TP
.B EPERM
-The file system containing
-.I newpath
+The filesystem containing
+.I linkpath
does not support the creation of symbolic links.
.TP
.B EROFS
-.I newpath
-is on a read-only file system.
-.SH "CONFORMING TO"
-SVr4, 4.3BSD, POSIX.1-2001.
+.I linkpath
+is on a read-only filesystem.
+.PP
+The following additional errors can occur for
+.BR symlinkat ():
+.TP
+.B EBADF
+.I newdirfd
+is not a valid file descriptor.
+.TP
+.B ENOENT
+.I linkpath
+is a relative pathname and
+.IR newdirfd
+refers to a directory that has been deleted.
+.TP
+.B ENOTDIR
+.I linkpath
+is relative and
+.I newdirfd
+is a file descriptor referring to a file other than a directory.
+.SH VERSIONS
+.BR symlinkat ()
+was added to Linux in kernel 2.6.16;
+library support was added to glibc in version 2.4.
+.SH CONFORMING TO
+.BR symlink ():
+SVr4, 4.3BSD, POSIX.1-2001, POSIX.1-2008.
.\" SVr4 documents additional error codes EDQUOT and ENOSYS.
.\" See
.\" .BR open (2)
.\" re multiple files with the same name, and NFS.
+
+.BR symlinkat ():
+POSIX.1-2008.
.SH NOTES
No checking of
-.I oldpath
+.I target
is done.
-Deleting the name referred to by a symlink will actually delete the
+Deleting the name referred to by a symbolic link will actually delete the
file (unless it also has other hard links).
If this behavior is not desired, use
.BR link (2).
-.SH "SEE ALSO"
+.SS Glibc notes
+On older kernels where
+.BR symlinkat ()
+is unavailable, the glibc wrapper function falls back to the use of
+.BR symlink (2).
+When
+.I linkpath
+is a relative pathname,
+glibc constructs a pathname based on the symbolic link in
+.IR /proc/self/fd
+that corresponds to the
+.IR newdirfd
+argument.
+.SH SEE ALSO
.BR ln (1),
.BR lchown (2),
.BR link (2),
.BR open (2),
.BR readlink (2),
.BR rename (2),
-.BR symlinkat (2),
.BR unlink (2),
.BR path_resolution (7),
.BR symlink (7)
+.SH COLOPHON
+This page is part of release 3.79 of the Linux
+.I man-pages
+project.
+A description of the project,
+information about reporting bugs,
+and the latest version of this page,
+can be found at
+\%http://www.kernel.org/doc/man\-pages/.
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