xref: /freebsd/lib/libc/gen/basename.3 (revision 7aa383846770374466b1dcb2cefd71bde9acf463)
1.\"
2.\" Copyright (c) 1997 Todd C. Miller <Todd.Miller@courtesan.com>
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27.\" $OpenBSD: basename.3,v 1.12 2000/04/18 03:01:25 aaron Exp $
28.\" $FreeBSD$
29.\"
30.Dd October 6, 2009
31.Dt BASENAME 3
32.Os
33.Sh NAME
34.Nm basename
35.Nd extract the base portion of a pathname
36.Sh SYNOPSIS
37.In libgen.h
38.Ft char *
39.Fn basename "const char *path"
40.Ft char *
41.Fn basename_r "const char *path" "char *bname"
42.Sh DESCRIPTION
43The
44.Fn basename
45function
46returns the last component from the pathname pointed to by
47.Fa path ,
48deleting any trailing
49.Sq \&/
50characters.
51If
52.Fa path
53consists entirely of
54.Sq \&/
55characters, a pointer to the string
56.Qq \&/
57is returned.
58If
59.Fa path
60is a null pointer or the empty string, a pointer to the string
61.Qq \&.
62is returned.
63.Pp
64The
65.Fn basename_r
66variation accepts a buffer of at least
67.Dv MAXPATHLEN
68bytes in which to store the resulting component.
69.Sh IMPLEMENTATION NOTES
70The
71.Fn basename
72function
73returns a pointer to internal storage space allocated on the first call
74that will be overwritten
75by subsequent calls.
76.Fn basename_r
77is therefore preferred for threaded applications.
78.Sh RETURN VALUES
79On successful completion,
80.Fn basename
81and
82.Fn basename_r
83return pointers to the last component of
84.Fa path .
85.Pp
86If they fail, a null pointer is returned and the global variable
87.Va errno
88is set to indicate the error.
89.Sh ERRORS
90The following error codes may be set in
91.Va errno :
92.Bl -tag -width Er
93.It Bq Er ENAMETOOLONG
94The path component to be returned was larger than
95.Dv MAXPATHLEN .
96.El
97.Sh SEE ALSO
98.Xr basename 1 ,
99.Xr dirname 1 ,
100.Xr dirname 3
101.Sh STANDARDS
102The
103.Fn basename
104function conforms to
105.St -xpg4.2 .
106.Sh HISTORY
107The
108.Fn basename
109function first appeared in
110.Ox 2.2
111and
112.Fx 4.2 .
113.Sh AUTHORS
114.An "Todd C. Miller" Aq Todd.Miller@courtesan.com
115