READLINKAT(2)

NAME
readlinkat - read value of a symbolic link relative to a directory file descriptor

SYNOPSIS
#define _ATFILE_SOURCE
#include <unistd.h>

int readlinkat(int dirfd, const char *pathname, char *buf, size_t bufsiz);

DESCRIPTION
The readlinkat() system call operates in exactly the same way as readlink(2), except for the differences described in this manual page. If the pathname given in pathname is relative, then it is interpreted relative to the directory referred to by the file descriptor dirfd (rather than relative to the current working directory of the calling process, as is done by readlink(2) for a relative pathname). If pathname is relative and dirfd is the special value AT_FDCWD, then pathname is interpreted relative to the current working directory of the calling process (like readlink(2)). If pathname is absolute, then dirfd is ignored.

RETURN VALUE
On success, readlinkat() returns 0. On error, -1 is returned and errno is set to indicate the error.

ERRORS
The same errors that occur for readlink(2) can also occur for readlinkat(). The following additional errors can occur for readlinkat():

EBADF
    dirfd is not a valid file descriptor.

ENOTDIR
    pathname is relative and dirfd is a file descriptor referring to a file other than a directory.

NOTES
See openat(2) for an explanation of the need for readlinkat().

CONFORMING TO
This system call is non-standard but is proposed for inclusion in a future revision of POSIX.1.

VERSIONS
readlinkat() was added to Linux in kernel 2.6.16.

SEE ALSO
openat(2), path_resolution(2), readlink(2)