xref: /freebsd/lib/libc/string/strchr.3 (revision f126890ac5386406dadf7c4cfa9566cbb56537c5)
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32.Dd February 13, 2013
33.Dt STRCHR 3
34.Os
35.Sh NAME
36.Nm strchr , strrchr , strchrnul
37.Nd locate character in string
38.Sh LIBRARY
39.Lb libc
40.Sh SYNOPSIS
41.In string.h
42.Ft "char *"
43.Fn strchr "const char *s" "int c"
44.Ft "char *"
45.Fn strrchr "const char *s" "int c"
46.Ft "char *"
47.Fn strchrnul "const char *s" "int c"
48.Sh DESCRIPTION
49The
50.Fn strchr
51function locates the first occurrence of
52.Fa c
53(converted to a
54.Vt char )
55in the string pointed to by
56.Fa s .
57The terminating null character is considered part of the string;
58therefore if
59.Fa c
60is
61.Ql \e0 ,
62the functions locate the terminating
63.Ql \e0 .
64.Pp
65The
66.Fn strrchr
67function is identical to
68.Fn strchr
69except it locates the last occurrence of
70.Fa c .
71.Pp
72The
73.Fn strchrnul
74function is identical to
75.Fn strchr
76except that if
77.Fa c
78is not found in
79.Fa s
80a pointer to the terminating
81.Ql \e0
82is returned.
83.Sh RETURN VALUES
84The functions
85.Fn strchr
86and
87.Fn strrchr
88return a pointer to the located character, or
89.Dv NULL
90if the character does not appear in the string.
91.Pp
92.Fn strchrnul
93returns a pointer to the terminating
94.Ql \e0
95if the character does not appear in the string.
96.Sh SEE ALSO
97.Xr memchr 3 ,
98.Xr memmem 3 ,
99.Xr strcspn 3 ,
100.Xr strpbrk 3 ,
101.Xr strsep 3 ,
102.Xr strspn 3 ,
103.Xr strstr 3 ,
104.Xr strtok 3 ,
105.Xr wcschr 3
106.Sh STANDARDS
107The functions
108.Fn strchr
109and
110.Fn strrchr
111conform to
112.St -isoC .
113The function
114.Fn strchrnul
115is a
116.Tn GNU
117extension.
118.Sh HISTORY
119The
120.Fn strchrnul
121function first appeared in glibc 2.1.1 and was added in
122.Fx 10.0 .
123