.\" 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/
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.\"
.TH WCSTOK 3  2013-11-18 "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
.I wcs
into tokens, where a token is
defined as a substring not containing any wide-characters from
.IR delim .
.PP
The search starts at
.IR wcs ,
if
.I wcs
is not NULL,
or at
.IR *ptr ,
if
.I wcs
is NULL.
First, any delimiter wide-characters are skipped, that is, the
pointer is advanced beyond any wide-characters which occur in
.IR delim .
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
.IR *ptr ,
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
.I delim
with
a null wide character (L\(aq\\0\(aq),
and it updates
.I *ptr
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 ATTRIBUTES
.SS Multithreading (see pthreads(7))
The
.BR wcstok ()
function is thread-safe.
.SH CONFORMING TO
C99.
.SH NOTES
The original
.I wcs
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 3.74 of the Linux
.I man-pages
project.
A description of the project,
information about reporting bugs,
and the latest version of this page,
can be found at
\%http://www.kernel.org/doc/man\-pages/.