Section: Linux Programmer's Manual (3)
dirfd - get directory stream file descriptor
int dirfd(DIR *dirp);
Feature Test Macro Requirements for glibc (see
/* Since glibc 2.10: */ _POSIX_C_SOURCE >= 200809L
|| /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
returns the file descriptor associated with the directory stream
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
It will be automatically closed when
On success, a nonnegative file descriptor is returned.
On error, -1 is returned, and
is set to indicate the cause of the error.
POSIX.1-2008 specifies two errors,
neither of which is returned by the current
does not refer to a valid directory stream.
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
This function was a BSD extension, present in 4.3BSD-Reno, not in 4.2BSD.
This page is part of release 5.02 of the Linux
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