xref: /openbsd/lib/libc/string/strrchr.3 (revision e5dd7070)
1.\"	$OpenBSD: strrchr.3,v 1.12 2018/10/01 06:37:37 martijn Exp $
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34.Dd $Mdocdate: October 1 2018 $
35.Dt STRRCHR 3
36.Os
37.Sh NAME
38.Nm strrchr ,
39.Nm rindex
40.Nd locate last occurrence of a character in a string
41.Sh SYNOPSIS
42.In string.h
43.Ft char *
44.Fn strrchr "const char *s" "int c"
45.In strings.h
46.Ft char *
47.Fn rindex "const char *s" "int c"
48.Sh DESCRIPTION
49The
50.Fn strrchr
51function locates the last occurrence of the character
52.Fa c
53.Pq converted to a char
54in the string
55.Fa s .
56The terminating
57.Tn NUL
58character is considered part of the string.
59If
60.Fa c
61is
62.Ql \e0 ,
63.Fn strrchr
64locates the terminating
65.Ql \e0 .
66.Pp
67The
68.Fn rindex
69function is an old synonym for
70.Fn strrchr .
71.Sh RETURN VALUES
72The
73.Fn strrchr
74function returns a pointer to the located character or
75.Dv NULL
76if the character does not appear in the string.
77.Sh EXAMPLES
78After the following call to
79.Fn strrchr ,
80.Va p
81will point to the string
82.Qq obar :
83.Bd -literal -offset indent
84char *p;
85char *s = "foobar";
86
87p = strrchr(s, 'o');
88.Ed
89.Sh SEE ALSO
90.Xr memchr 3 ,
91.Xr strchr 3 ,
92.Xr strcspn 3 ,
93.Xr strpbrk 3 ,
94.Xr strsep 3 ,
95.Xr strspn 3 ,
96.Xr strstr 3 ,
97.Xr strtok 3 ,
98.Xr wcsrchr 3
99.Sh STANDARDS
100The
101.Fn strrchr
102function conforms to
103.St -ansiC .
104.Pp
105The
106.Fn rindex
107function is deprecated and shouldn't be used in new code.
108.Sh HISTORY
109The
110.Fn rindex
111function first appeared in
112.At v7 .
113The
114.Fn strrchr
115function first appeared in
116.At III
117and was reimplemented for
118.Bx 4.3 Tahoe .
119