DIRFD(3) Linux Programmer s Manual DIRFD(3)
NAME dirfd - get directory stream file descriptor
SYNOPSIS #include <sys/types.h> #include <dirent.h>
int dirfd(DIR *dirp);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
dirfd(): _BSD_SOURCE || _SVID_SOURCE
DESCRIPTION The function dirfd() returns the file descriptor associated with the directory stream dirp.
This descriptor is the one used internally by the directory stream. As a result, it is only useful 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.
RETURN VALUE On success, a non-negative file descriptor is returned. On error, -1 is returned.
ERRORS 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.
CONFORMING TO POSIX.1-2008. This function was a BSD extension, present in 4.3BSD- Reno, not in 4.2BSD.
NOTES The prototype for dirfd() is only available if _BSD_SOURCE or _SVID_SOURCE is defined.
SEE ALSO open(2), closedir(3), opendir(3), readdir(3), rewinddir(3), scandir(3), seekdir(3), telldir(3)
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/.
Linux 2008-08-21 DIRFD(3)