man3/wcsstr.3

.\" Copyright (c) Bruno Haible <haible@clisp.cons.org>
.\"
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.\" References consulted:
.\"   GNU glibc-2 source code and manual
.\"   Dinkumware C library reference http://www.dinkumware.com/
.\"   OpenGroup's Single UNIX specification http://www.UNIX-systems.org/online.html
.\"   ISO/IEC 9899:1999
.\"
.TH WCSSTR 3  2021-03-22 "GNU" "Linux Programmer's Manual"
.SH NAME
wcsstr \- locate a substring in a wide-character string
.SH SYNOPSIS
.nf
.B #include <wchar.h>
.PP
.BI "wchar_t *wcsstr(const wchar_t *" haystack ", const wchar_t *" needle );
.fi
.SH DESCRIPTION
The
.BR wcsstr ()
function is the wide-character equivalent of the
.BR strstr (3)
function.
It searches for the first occurrence of the wide-character string
.I needle
(without its terminating null wide character (L\(aq\e0\(aq))
as a substring in the wide-character string
.IR haystack .
.SH RETURN VALUE
The
.BR wcsstr ()
function returns a pointer to the first occurrence of
.I needle
in
.IR haystack .
It returns NULL if
.I needle
does not occur
as a substring in
.IR haystack .
.PP
Note the special case:
If
.I needle
is the empty wide-character string,
the return value is always
.I haystack
itself.
.SH ATTRIBUTES
For an explanation of the terms used in this section, see
.BR attributes (7).
.ad l
.nh
.TS
allbox;
lbx lb lb
l l l.
Interface	Attribute	Value
T{
.BR wcsstr ()
T}	Thread safety	MT-Safe
.TE
.hy
.ad
.sp 1
.SH CONFORMING TO
POSIX.1-2001, POSIX.1-2008, C99.
.SH SEE ALSO
.BR strstr (3),
.BR wcschr (3)