1DIRFD(3)                   Linux Programmer's Manual                  DIRFD(3)
2
3
4

NAME

6       dirfd - get directory stream file descriptor
7

SYNOPSIS

9       #include <sys/types.h>
10       #include <dirent.h>
11
12       int dirfd(DIR *dirp);
13
14   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
15
16       dirfd():
17           /* Since glibc 2.10: */ _POSIX_C_SOURCE >= 200809L
18               || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
19

DESCRIPTION

21       The  function  dirfd()  returns the file descriptor associated with the
22       directory stream dirp.
23
24       This file descriptor is  the  one  used  internally  by  the  directory
25       stream.   As  a  result,  it  is useful only for functions which do not
26       depend on or alter the file position, such as fstat(2)  and  fchdir(2).
27       It will be automatically closed when closedir(3) is called.
28

RETURN VALUE

30       On success, a nonnegative file descriptor is returned.  On error, -1 is
31       returned, and errno is set to indicate the cause of the error.
32

ERRORS

34       POSIX.1-2008 specifies two errors, neither of which is returned by  the
35       current implementation.
36
37       EINVAL dirp does not refer to a valid directory stream.
38
39       ENOTSUP
40              The  implementation  does  not support the association of a file
41              descriptor with a directory.
42

ATTRIBUTES

44       For  an  explanation  of  the  terms  used   in   this   section,   see
45       attributes(7).
46
47       ┌──────────┬───────────────┬─────────┐
48       │Interface │ Attribute     │ Value   │
49       ├──────────┼───────────────┼─────────┤
50       │dirfd()   │ Thread safety │ MT-Safe │
51       └──────────┴───────────────┴─────────┘

CONFORMING TO

53       POSIX.1-2008.   This  function  was a BSD extension, present in 4.3BSD-
54       Reno, not in 4.2BSD.
55

SEE ALSO

57       open(2), closedir(3), opendir(3), readdir(3), rewinddir(3), scandir(3),
58       seekdir(3), telldir(3)
59

COLOPHON

61       This  page  is  part of release 4.16 of the Linux man-pages project.  A
62       description of the project, information about reporting bugs,  and  the
63       latest     version     of     this    page,    can    be    found    at
64       https://www.kernel.org/doc/man-pages/.
65
66
67
68Linux                             2016-03-15                          DIRFD(3)
Impressum