READLINK(2) BSD System Calls Manual READLINK(2)
NAME
readlink -- read value of a symbolic link
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <unistd.h>
ssize_t
readlink(const char * restrict path, char * restrict 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 NUL charac-
ter to buf.
RETURN VALUES
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 the
global variable errno.
EXAMPLES
A typical use is illustrated in the following piece of code which reads the contents of a symbolic link named /symbolic/link and stores them
as null-terminated string:
#include <limits.h>
#include <unistd.h>
char buf[PATH_MAX];
ssize_t len;
if ((len = readlink("/symbolic/link", buf, sizeof(buf)-1)) == -1)
error handling;
buf[len] = ' ';
ERRORS
readlink() will fail if:
[ENOTDIR] A component of the path prefix is not a directory.
[ENAMETOOLONG] A component of a pathname exceeded {NAME_MAX} characters, or an entire path name exceeded {PATH_MAX} characters.
[ENOENT] The named file does not exist.
[EACCES] Search permission is denied for a component of the path prefix.
[ELOOP] Too many symbolic links were encountered in translating the pathname.
[EINVAL] The named file is not a symbolic link.
[EIO] An I/O error occurred while reading from the file system.
[EFAULT] buf extends outside the process's allocated address space.
SEE ALSO
lstat(2), stat(2), symlink(2), symlink(7)
STANDARDS
The readlink() function conforms to IEEE Std 1003.1-2001 (``POSIX.1'').
HISTORY
The readlink() function appeared in 4.2BSD. The type returned was changed from int to ssize_t in NetBSD 2.1.
BSD
May 11, 2004 BSD
