- Uniformly use .In for header file references.
[dragonfly.git] / share / man / man5 / dir.5
CommitLineData
984263bc
MD
1.\" Copyright (c) 1983, 1991, 1993
2.\" The Regents of the University of California. All rights reserved.
3.\"
4.\" Redistribution and use in source and binary forms, with or without
5.\" modification, are permitted provided that the following conditions
6.\" are met:
7.\" 1. Redistributions of source code must retain the above copyright
8.\" notice, this list of conditions and the following disclaimer.
9.\" 2. Redistributions in binary form must reproduce the above copyright
10.\" notice, this list of conditions and the following disclaimer in the
11.\" documentation and/or other materials provided with the distribution.
12.\" 3. All advertising materials mentioning features or use of this software
13.\" must display the following acknowledgement:
14.\" This product includes software developed by the University of
15.\" California, Berkeley and its contributors.
16.\" 4. Neither the name of the University nor the names of its contributors
17.\" may be used to endorse or promote products derived from this software
18.\" without specific prior written permission.
19.\"
20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30.\" SUCH DAMAGE.
31.\"
32.\" @(#)dir.5 8.3 (Berkeley) 4/19/94
33.\" $FreeBSD: src/share/man/man5/dir.5,v 1.12.2.5 2001/12/17 11:30:13 ru Exp $
44cb301e 34.\" $DragonFly: src/share/man/man5/dir.5,v 1.7 2006/05/26 19:39:40 swildner Exp $
984263bc 35.\"
d4e8e477 36.Dd March 5, 2005
984263bc
MD
37.Dt DIR 5
38.Os
39.Sh NAME
40.Nm dir ,
41.Nm dirent
42.Nd directory file format
43.Sh SYNOPSIS
44.In dirent.h
45.Sh DESCRIPTION
46Directories provide a convenient hierarchical method of grouping
47files while obscuring the underlying details of the storage medium.
48A directory file is differentiated from a plain file
49by a flag in its
50.Xr inode 5
51entry.
52It consists of records (directory entries) each of which contains
53information about a file and a pointer to the file itself.
54Directory entries may contain other directories
55as well as plain files; such nested directories are referred to as
56subdirectories.
57A hierarchy of directories and files is formed in this manner
58and is called a file system (or referred to as a file system tree).
59.\" An entry in this tree,
60.\" nested or not nested,
61.\" is a pathname.
62.Pp
63Each directory file contains two special directory entries; one is a pointer
64to the directory itself
65called dot
66.Ql .\&
67and the other a pointer to its parent directory called dot-dot
68.Ql \&.. .
69Dot and dot-dot
70are valid pathnames, however,
71the system root directory
72.Ql / ,
73has no parent and dot-dot points to itself like dot.
74.Pp
75File system nodes are ordinary directory files on which has
76been grafted a file system object, such as a physical disk or a
77partitioned area of such a disk.
78(See
79.Xr mount 2
80and
81.Xr mount 8 . )
82.Pp
d4e8e477 83The directory entry format is defined in
44cb301e 84.In sys/dirent.h .
d4e8e477 85This file should not be included directly by applications.
984263bc
MD
86.Sh SEE ALSO
87.Xr fs 5 ,
88.Xr inode 5
984263bc
MD
89.Sh HISTORY
90A
91.Nm
92file format appeared in
93.At v7 .
ac561d34
SW
94.Sh BUGS
95The usage of the member d_type of struct dirent is unportable as it is
96.Dx Ns / Ns Fx Ns -specific .
97It also may fail on certain filesystems, for example the cd9660 filesystem.