xref: /freebsd/lib/libc/string/strchr.3 (revision dc36d6f9bb1753f3808552f3afd30eda9a7b206a)

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.Dd February 13, 2013
.Dt STRCHR 3
.Os
.Sh NAME
.Nm strchr , strrchr , strchrnul
.Nd locate character in string
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In string.h
.Ft "char *"
.Fn strchr "const char *s" "int c"
.Ft "char *"
.Fn strrchr "const char *s" "int c"
.Ft "char *"
.Fn strchrnul "const char *s" "int c"
.Sh DESCRIPTION
The
.Fn strchr
function locates the first occurrence of
.Fa c
(converted to a
.Vt char )
in the string pointed to by
.Fa s .
The terminating null character is considered part of the string;
therefore if
.Fa c
is
.Ql \e0 ,
the functions locate the terminating
.Ql \e0 .
.Pp
The
.Fn strrchr
function is identical to
.Fn strchr
except it locates the last occurrence of
.Fa c .
.Pp
The
.Fn strchrnul
function is identical to
.Fn strchr
except that if
.Fa c
is not found in
.Fa s
a pointer to the terminating
.Ql \e0
is returned.
.Sh RETURN VALUES
The functions
.Fn strchr
and
.Fn strrchr
return a pointer to the located character, or
.Dv NULL
if the character does not appear in the string.
.Pp
.Fn strchrnul
returns a pointer to the terminating
.Ql \e0
if the character does not appear in the string.
.Sh SEE ALSO
.Xr memchr 3 ,
.Xr memmem 3 ,
.Xr strcspn 3 ,
.Xr strpbrk 3 ,
.Xr strsep 3 ,
.Xr strspn 3 ,
.Xr strstr 3 ,
.Xr strtok 3 ,
.Xr wcschr 3
.Sh STANDARDS
The functions
.Fn strchr
and
.Fn strrchr
conform to
.St -isoC .
The function
.Fn strchrnul
is a
.Tn GNU
extension.
.Sh HISTORY
The
.Fn strchrnul
function first appeared in glibc 2.1.1 and was added in
.Fx 10.0 .