.\"	$OpenBSD: wcstok.3,v 1.7 2011/07/25 00:38:53 schwarze Exp $
.\"
.\" $NetBSD: wcstok.3,v 1.3 2003/09/08 17:54:33 wiz Exp $
.\"
.\" Copyright (c) 1998 Softweyr LLC.  All rights reserved.
.\"
.\" strtok_r, from Berkeley strtok
.\" Oct 13, 1998 by Wes Peters <wes@softweyr.com>
.\"
.\" Copyright (c) 1988, 1991, 1993
.\"	The Regents of the University of California.  All rights reserved.
.\"
.\" This code is derived from software contributed to Berkeley by
.\" the American National Standards Committee X3, on Information
.\" Processing Systems.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\"
.\" 1. Redistributions of source code must retain the above copyright
.\"    notices, this list of conditions and the following disclaimer.
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.\" 2. Redistributions in binary form must reproduce the above
.\"    copyright notices, this list of conditions and the following
.\"    disclaimer in the documentation and/or other materials provided
.\"    with the distribution.
.\"
.\" 3. All advertising materials mentioning features or use of this
.\"    software must display the following acknowledgement:
.\"
.\"	This product includes software developed by Softweyr LLC, the
.\"      University of California, Berkeley, and its contributors.
.\"
.\" 4. Neither the name of Softweyr LLC, the University nor the names
.\"    of its contributors may be used to endorse or promote products
.\"    derived from this software without specific prior written
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.\" CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
.\" INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
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.\" Original version ID:
.\" FreeBSD: src/lib/libc/string/wcstok.3,v 1.4 2002/10/15 09:49:54 tjr Exp
.\"
.Dd $Mdocdate: July 25 2011 $
.Dt WCSTOK 3
.Os
.Sh NAME
.Nm wcstok
.Nd split wide-character string into tokens
.Sh SYNOPSIS
.In wchar.h
.Ft wchar_t *
.Fn wcstok "wchar_t * restrict str" "const wchar_t * restrict sep" "wchar_t ** restrict last"
.Sh DESCRIPTION
The
.Fn wcstok
function
is used to isolate sequential tokens in a NUL-terminated wide-character
string,
.Fa str .
These tokens are separated in the string by at least one of the
characters in
.Fa sep .
The first time that
.Fn wcstok
is called,
.Fa str
should be specified; subsequent calls, wishing to obtain further tokens
from the same string, should pass a null pointer instead.
The separator string,
.Fa sep ,
must be supplied each time, and may change between calls.
The context pointer
.Fa last
must be provided on each call.
.Pp
The
.Fn wcstok
function is the wide-character counterpart of the
.Xr strtok_r 3
function.
.Pp
Since
.Fn wcstok
modifies the string,
.Fa str
should not point to an area in the initialized data segment.
.Sh RETURN VALUES
The
.Fn wcstok
function
returns a pointer to the beginning of each subsequent token in the string,
after replacing the token itself with a NUL wide character (L'\e0').
When no more tokens remain, a null pointer is returned.
.Sh EXAMPLES
The following code fragment splits a wide-character string on
.Tn ASCII
space, tab, and newline characters and writes the tokens to
standard output:
.Bd -literal -offset indent
const wchar_t *seps = L" \et\en";
wchar_t *last, *tok, text[] = L" \enone\ettwo\et\etthree  \en";

for (tok = wcstok(text, seps, &last); tok != NULL;
    tok = wcstok(NULL, seps, &last))
	wprintf(L"%ls\en", tok);
.Ed
.Sh SEE ALSO
.Xr strtok 3 ,
.Xr wcschr 3 ,
.Xr wcscspn 3 ,
.Xr wcspbrk 3 ,
.Xr wcsrchr 3 ,
.Xr wcsspn 3 ,
.Xr wcsstr 3 ,
.Xr wmemchr 3
.Sh STANDARDS
The
.Fn wcstok
function
conforms to
.St -isoC-99 .
.Sh HISTORY
The
.Fn wcstok
function was ported from
.Nx
and first appeared in
.Ox 3.8 .
.Pp
Some early implementations of
.Fn wcstok
omit the
context pointer argument,
.Fa last ,
and maintain state across calls in a static variable like
.Xr strtok 3
does.