READLINK(2) System Calls Manual READLINK(2)
NAME
readlinkread 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 character 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] = '\0';
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
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.