readlinkat

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

#define _ATFILE_SOURCE
#include <unistd.h>
 I int readlinkat(int  dirfd , const char * pathname \
", char *" buf ", size_t " bufsiz );

The R 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 R 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 R AT_FDCWD , then pathname is interpreted relative to the current working directory of the calling process (like readlink(2)). If R pathname is absolute, then dirfd is ignored.

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

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

EBADF

ENOTDIR

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

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

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

openat(2), readlink(2), path_resolution(7)