Name
readlink — read value of a symbolic link
Synopsis
#include <unistd.h>
ssize_t readlink( |
const char * |
path, |
|
char * |
buf, |
|
size_t |
bufsiz) ; |
DESCRIPTION
readlink
() places the
contents of the symbolic link path
in the buffer buf
, which has size bufsiz
. readlink
() does not append a null byte to
buf
. It will truncate
the contents (to a length of bufsiz
characters), in case the
buffer is too small to hold all of the contents.
RETURN VALUE
The call returns the count of characters placed in the
buffer if it succeeds, or a −1 if an error occurs,
placing the error code in errno
.
ERRORS
- EACCES
-
Search permission is denied for a component of the
path prefix. (See also path_resolution(7).)
- EFAULT
-
buf
extends
outside the process's allocated address space.
- EINVAL
-
bufsiz
is
not positive.
- EINVAL
-
The named file is not a symbolic link.
- EIO
-
An I/O error occurred while reading from the file
system.
- ELOOP
-
Too many symbolic links were encountered in
translating the pathname.
- ENAMETOOLONG
-
A pathname, or a component of a pathname, was too
long.
- ENOENT
-
The named file does not exist.
- ENOMEM
-
Insufficient kernel memory was available.
- ENOTDIR
-
A component of the path prefix is not a
directory.
CONFORMING TO
4.4BSD (the readlink
()
function call appeared in 4.2BSD), POSIX.1-2001.
NOTES
In versions of glibc up to and including glibc 2.4, the
return type of readlink
() was
declared as int
.
Nowadays, the return type is declared as ssize_t
, as (newly) required
in POSIX.1-2001.
SEE ALSO
lstat(2), readlinkat(2), stat(2), symlink(2), path_resolution(7)
Copyright (c) 1983, 1991 The Regents of the University of California.
All rights reserved.
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are met:
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must display the following acknowledgement:
This product includes software developed by the University of
California, Berkeley and its contributors.
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@(#)readlink.2
6.8 (Berkeley) 3/10/91
Modified Sat Jul 24 00:10:21 1993 by Rik Faith (faith@cs.unc.edu)
Modified Tue Jul 9 23:55:17 1996 by aeb
Modified Fri Jan 24 00:26:00 1997 by aeb
|