.\" Copyright (c) Bruno Haible <haible@clisp.cons.org>
.\"
.\" This is free documentation; you can redistribute it and/or
.\" modify it under the terms of the GNU General Public License as
.\" published by the Free Software Foundation; either version 2 of
.\" the License, or (at your option) any later version.
.\"
.\" 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 WCSTOK 3  1999-07-25 "GNU" "Linux Programmer's Manual"
.SH NAME
wcstok \- split wide-character string into tokens
.SH SYNOPSIS
.nf
.B #include <wchar.h>
.sp
.BI "wchar_t *wcstok(wchar_t *" wcs ", const wchar_t *" delim \
", wchar_t **" ptr );
.fi
.SH DESCRIPTION
The
.BR wcstok ()
function is the wide-character equivalent of the
.BR strtok (3)
function,
with an added argument to make it multithread-safe.
It can be used
to split a wide-character string \fIwcs\fP into tokens, where a token is
defined as a substring not containing any wide-characters from \fIdelim\fP.
.PP
The search starts at \fIwcs\fP, if \fIwcs\fP is not NULL,
or at \fI*ptr\fP, if \fIwcs\fP is NULL.
First, any delimiter wide-characters are skipped, that is, the
pointer is advanced beyond any wide-characters which occur in \fIdelim\fP.
If the end of the wide-character string is now
reached,
.BR wcstok ()
returns NULL, to indicate that no tokens
were found, and stores an appropriate value in \fI*ptr\fP,
so that subsequent calls to
.BR wcstok ()
will continue to return NULL.
Otherwise, the
.BR wcstok ()
function recognizes the beginning of a token
and returns a pointer to it, but before doing that, it zero-terminates the
token by replacing the next wide-character which occurs in \fIdelim\fP with
a L\(aq\\0\(aq character,
and it updates \fI*ptr\fP so that subsequent calls will
continue searching after the end of recognized token.
.SH "RETURN VALUE"
The
.BR wcstok ()
function returns a pointer to the next token,
or NULL if no further token was found.
.SH "CONFORMING TO"
C99.
.SH NOTES
The original \fIwcs\fP wide-character string is destructively modified during
the operation.
.SH EXAMPLE
The following code loops over the tokens contained in a wide-character string.
.sp
.nf
wchar_t *wcs = ...;
wchar_t *token;
wchar_t *state;
for (token = wcstok(wcs, " \\t\\n", &state);
    token != NULL;
    token = wcstok(NULL, " \\t\\n", &state)) {
    ...
}
.fi
.SH "SEE ALSO"
.BR strtok (3),
.BR wcschr (3)
.SH COLOPHON
This page is part of release 3.22 of the Linux
.I man-pages
project.
A description of the project,
and information about reporting bugs,
can be found at
http://www.kernel.org/doc/man-pages/.
