dirfd - Man Page

Standard C library (libc, -lc)

#include <sys/types.h>
#include <dirent.h>

int dirfd(DIR *dirp);

dirfd():

    /* Since glibc 2.10: */ _POSIX_C_SOURCE >= 200809L
        || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE

The function dirfd() returns the file descriptor associated with the directory stream dirp.

This file descriptor is the one used internally by the directory stream. As a result, it is useful only for functions which do not depend on or alter the file position, such as fstat(2) and fchdir(2). It will be automatically closed when closedir(3) is called.

On success, dirfd() returns a file descriptor (a nonnegative integer). On error, -1 is returned, and errno is set to indicate the error.

POSIX.1-2008 specifies two errors, neither of which is returned by the current implementation.

EINVAL

dirp does not refer to a valid directory stream.

ENOTSUP

The implementation does not support the association of a file descriptor with a directory.

For an explanation of the terms used in this section, see attributes(7).

POSIX.1-2008.

4.3BSD-Reno (not in 4.2BSD).

open(2), openat(2), closedir(3), opendir(3), readdir(3), rewinddir(3), scandir(3), seekdir(3), telldir(3)

open(2), opendir(3), perl5220delta(1), perlapi(1), perlfunc(1), readdir(3).