xref: /freebsd/lib/libc/gen/basename.3 (revision 63d1fd5970ec814904aa0f4580b10a0d302d08b2)
1.\" $OpenBSD: basename.3,v 1.20 2007/05/31 19:19:28 jmc Exp $
2.\"
3.\" Copyright (c) 1997 Todd C. Miller <Todd.Miller@courtesan.com>
4.\"
5.\" Permission to use, copy, modify, and distribute this software for any
6.\" purpose with or without fee is hereby granted, provided that the above
7.\" copyright notice and this permission notice appear in all copies.
8.\"
9.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
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13.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
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15.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16.\"
17.\" $FreeBSD$
18.\"
19.Dd October 29, 2016
20.Dt BASENAME 3
21.Os
22.Sh NAME
23.Nm basename
24.Nd extract the base portion of a pathname
25.Sh SYNOPSIS
26.In libgen.h
27.Ft char *
28.Fn basename "char *path"
29.Sh DESCRIPTION
30The
31.Fn basename
32function returns the last component from the pathname pointed to by
33.Fa path ,
34deleting any trailing
35.Sq \&/
36characters.
37.Sh RETURN VALUES
38If
39.Fa path
40consists entirely of
41.Sq \&/
42characters, a pointer to the string
43.Qq \&/
44is returned.
45If
46.Fa path
47is a null pointer or the empty string, a pointer to the string
48.Qq \&.
49is returned.
50Otherwise,
51it returns a pointer to the last component of
52.Fa path .
53.Sh IMPLEMENTATION NOTES
54This implementation of
55.Fn basename
56uses the buffer provided by the caller to store the resulting pathname
57component.
58Other vendor implementations may return a pointer to internal storage
59space instead.
60The advantage of the former approach is that it ensures thread-safety,
61while also placing no upper limit on the supported length of the
62pathname.
63.Sh SEE ALSO
64.Xr basename 1 ,
65.Xr dirname 1 ,
66.Xr dirname 3
67.Sh STANDARDS
68The
69.Fn basename
70function conforms to
71.St -xpg4.2 .
72.Sh HISTORY
73The
74.Fn basename
75function first appeared in
76.Ox 2.2
77and
78.Fx 4.2 .
79.Pp
80In
81.Fx 12.0 ,
82this function was reimplemented to store its result in the provided
83input buffer.
84There is no longer any need to use the
85.Fn basename_r
86function.
87.Sh AUTHORS
88.An Nuxi, the Netherlands
89