NAME¶

readlink - read value of a symbolic link

SYNOPSIS¶

#include <unistd.h>

ssize_t readlink(const char *path, char *buf, size_t bufsiz);

Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

readlink(): _BSD_SOURCE || _XOPEN_SOURCE >= 500 || _POSIX_C_SOURCE >= 200112L

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¶

On success, readlink() returns the number of bytes placed in buf. On error, -1 is returned and errno is set to indicate the error.

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), symlink(7)

COLOPHON¶

This page is part of release 3.22 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.