lib/libc/string/strstr.3 - master - nerfur/openbsd-src

lib/libc/string/strstr.3
101 строка3 KB
schwarze
Add RETURN VALUES section and .Xr to memmem(3).
11 май 2016, 20:51
11 май 2016, 20:5163dd848
.\"	$OpenBSD: strstr.3,v 1.13 2016/05/11 17:51:50 schwarze Exp $
.\"
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.Dd $Mdocdate: May 11 2016 $
.Dt STRSTR 3
.Os
.Sh NAME
.Nm strstr , strcasestr
.Nd locate a substring in a string
.Sh SYNOPSIS
.In string.h
.Ft char *
.Fn strstr "const char *big" "const char *little"
.Ft char *
.Fn strcasestr "const char *big" "const char *little"
.Sh DESCRIPTION
The
.Fn strstr
function locates the first occurrence of the NUL-terminated string
.Fa little
in the NUL-terminated string
.Fa big .
.Pp
The
.Fn strcasestr
function is similar to
.Fn strstr
but ignores the case of both strings.
.Sh RETURN VALUES
If
.Fa little
is an empty string,
.Fa big
is returned;
if
.Fa little
occurs nowhere in
.Fa big ,
.Dv NULL
is returned;
otherwise a pointer to the first character of the first occurrence of
.Fa little
is returned.
.Sh SEE ALSO
.Xr memchr 3 ,
.Xr memmem 3 ,
.Xr strchr 3 ,
.Xr strcspn 3 ,
.Xr strpbrk 3 ,
.Xr strrchr 3 ,
.Xr strsep 3 ,
.Xr strspn 3 ,
.Xr strtok 3 ,
.Xr wcsstr 3
.Sh STANDARDS
The
.Fn strstr
function conforms to
.St -ansiC .
.Sh HISTORY
The
.Fn strstr
function first appeared in
.Bx 4.3 Reno .
The
.Fn strcasestr
function appeared in glibc 2.1,
was reimplemented for
.Fx 4.5
and ported to
.Ox 3.8 .