freebsd-dev/lib/libc/sys/symlink.2

207 lines
5.6 KiB
Groff
Raw Normal View History

1994-05-27 05:00:24 +00:00
.\" Copyright (c) 1983, 1991, 1993
.\" The Regents of the University of California. All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\" notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\" notice, this list of conditions and the following disclaimer in the
.\" documentation and/or other materials provided with the distribution.
.\" 4. Neither the name of the University nor the names of its contributors
.\" may be used to endorse or promote products derived from this software
.\" without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\" @(#)symlink.2 8.1 (Berkeley) 6/4/93
1999-08-28 00:22:10 +00:00
.\" $FreeBSD$
1994-05-27 05:00:24 +00:00
.\"
.Dd April 10, 2008
1994-05-27 05:00:24 +00:00
.Dt SYMLINK 2
.Os
1994-05-27 05:00:24 +00:00
.Sh NAME
.Nm symlink ,
.Nm symlinkat
1994-05-27 05:00:24 +00:00
.Nd make symbolic link to a file
.Sh LIBRARY
.Lb libc
1994-05-27 05:00:24 +00:00
.Sh SYNOPSIS
.In unistd.h
1994-05-27 05:00:24 +00:00
.Ft int
.Fn symlink "const char *name1" "const char *name2"
.Ft int
.Fn symlinkat "const char *name1" "int fd" "const char *name2"
1994-05-27 05:00:24 +00:00
.Sh DESCRIPTION
A symbolic link
.Fa name2
is created to
.Fa name1
.Fa ( name2
1994-05-27 05:00:24 +00:00
is the name of the
file created,
.Fa name1
is the string
used in creating the symbolic link).
Either name may be an arbitrary path name; the files need not
be on the same file system.
.Pp
The
.Fn symlinkat
system call is equivalent to
.Fn symlink
except in the case where
.Fa name2
specifies a relative path.
In this case the symbolic link is created relative to the directory
associated with the file descriptor
.Fa fd
instead of the current working directory.
If
.Fn symlinkat
is passed the special value
.Dv AT_FDCWD
in the
.Fa fd
parameter, the current working directory is used and the behavior is
identical to a call to
.Fn symlink .
1994-05-27 05:00:24 +00:00
.Sh RETURN VALUES
.Rv -std symlink
1994-05-27 05:00:24 +00:00
.Sh ERRORS
The symbolic link succeeds unless:
.Bl -tag -width Er
1994-05-27 05:00:24 +00:00
.It Bq Er ENOTDIR
A component of the
.Fa name2
2006-12-12 19:57:17 +00:00
path prefix is not a directory.
1994-05-27 05:00:24 +00:00
.It Bq Er ENAMETOOLONG
A component of the
.Fa name2
pathname exceeded 255 characters,
1994-05-27 05:00:24 +00:00
or the entire length of either path name exceeded 1023 characters.
.It Bq Er ENOENT
2006-12-12 19:57:17 +00:00
A component of the
.Fa name2
path prefix does not exist.
1994-05-27 05:00:24 +00:00
.It Bq Er EACCES
A component of the
.Fa name2
path prefix denies search permission, or write permission is denied on the
parent directory of the file to be created.
1994-05-27 05:00:24 +00:00
.It Bq Er ELOOP
Too many symbolic links were encountered in translating the
.Fa name2
path name.
1994-05-27 05:00:24 +00:00
.It Bq Er EEXIST
2002-12-19 09:40:28 +00:00
The path name pointed at by the
.Fa name2
argument
1994-05-27 05:00:24 +00:00
already exists.
.It Bq Er EPERM
The parent directory of the file named by
.Fa name2
has its immutable flag set, see the
.Xr chflags 2
manual page for more information.
1994-05-27 05:00:24 +00:00
.It Bq Er EIO
An I/O error occurred while making the directory entry for
.Fa name2 ,
or allocating the inode for
.Fa name2 ,
or writing out the link contents of
.Fa name2 .
.It Bq Er EROFS
The file
.Fa name2
would reside on a read-only file system.
.It Bq Er ENOSPC
The directory in which the entry for the new symbolic link is being placed
cannot be extended because there is no space left on the file
system containing the directory.
.It Bq Er ENOSPC
The new symbolic link cannot be created because
1994-05-27 05:00:24 +00:00
there is no space left on the file
system that will contain the symbolic link.
.It Bq Er ENOSPC
There are no free inodes on the file system on which the
symbolic link is being created.
.It Bq Er EDQUOT
The directory in which the entry for the new symbolic link
is being placed cannot be extended because the
user's quota of disk blocks on the file system
containing the directory has been exhausted.
.It Bq Er EDQUOT
The new symbolic link cannot be created because the user's
quota of disk blocks on the file system that will
contain the symbolic link has been exhausted.
.It Bq Er EDQUOT
The user's quota of inodes on the file system on
which the symbolic link is being created has been exhausted.
.It Bq Er EIO
An I/O error occurred while making the directory entry or allocating the inode.
.It Bq Er EFAULT
2002-12-19 09:40:28 +00:00
The
.Fa name1
1994-05-27 05:00:24 +00:00
or
.Fa name2
2002-12-19 09:40:28 +00:00
argument
1994-05-27 05:00:24 +00:00
points outside the process's allocated address space.
.El
.Pp
In addition to the errors returned by the
.Fn symlink ,
the
.Fn symlinkat
may fail if:
.Bl -tag -width Er
.It Bq Er EBADF
The
.Fa name2
argument does not specify an absolute path and the
.Fa fd
argument is neither
.Dv AT_FDCWD
nor a valid file descriptor open for searching.
.It Bq Er ENOTDIR
The
.Fa name2
argument is not an absolute path and
.Fa fd
is neither
.Dv AT_FDCWD
nor a file descriptor associated with a directory.
.El
1994-05-27 05:00:24 +00:00
.Sh SEE ALSO
.Xr ln 1 ,
.Xr chflags 2 ,
.Xr link 2 ,
.Xr lstat 2 ,
.Xr readlink 2 ,
1997-01-20 23:23:22 +00:00
.Xr unlink 2 ,
.Xr symlink 7
.Sh STANDARDS
The
.Fn symlinkat
system call follows The Open Group Extended API Set 2 specification.
1994-05-27 05:00:24 +00:00
.Sh HISTORY
The
.Fn symlink
system call appeared in
1994-05-27 05:00:24 +00:00
.Bx 4.2 .
The
.Fn symlinkat
system call appeared in
.Fx 8.0 .