xref: /minix3/lib/libc/string/wcstok.3 (revision 2fe8fb192fe7e8720e3e7a77f928da545e872a6a)

.\" $NetBSD: wcstok.3,v 1.6 2010/12/16 17:42:28 wiz Exp $
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.\" strtok_r, from Berkeley strtok
.\" Oct 13, 1998 by Wes Peters <wes@softweyr.com>
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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 October 3, 2002
.Dt WCSTOK 3
.Os
.Sh NAME
.Nm wcstok
.Nd split wide-character string into tokens
.Sh LIBRARY
.Lb libc
.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
.Fn strtok_r
function.
.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
.Sh STANDARDS
The
.Fn wcstok
function
conforms to
.St -isoC-99 .
.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.