xref: /openbsd/lib/libc/string/wcstok.3 (revision fc61954a)
1.\"	$OpenBSD: wcstok.3,v 1.7 2011/07/25 00:38:53 schwarze Exp $
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3.\" $NetBSD: wcstok.3,v 1.3 2003/09/08 17:54:33 wiz Exp $
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5.\" Copyright (c) 1998 Softweyr LLC.  All rights reserved.
6.\"
7.\" strtok_r, from Berkeley strtok
8.\" Oct 13, 1998 by Wes Peters <wes@softweyr.com>
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54.\" Original version ID:
55.\" FreeBSD: src/lib/libc/string/wcstok.3,v 1.4 2002/10/15 09:49:54 tjr Exp
56.\"
57.Dd $Mdocdate: July 25 2011 $
58.Dt WCSTOK 3
59.Os
60.Sh NAME
61.Nm wcstok
62.Nd split wide-character string into tokens
63.Sh SYNOPSIS
64.In wchar.h
65.Ft wchar_t *
66.Fn wcstok "wchar_t * restrict str" "const wchar_t * restrict sep" "wchar_t ** restrict last"
67.Sh DESCRIPTION
68The
69.Fn wcstok
70function
71is used to isolate sequential tokens in a NUL-terminated wide-character
72string,
73.Fa str .
74These tokens are separated in the string by at least one of the
75characters in
76.Fa sep .
77The first time that
78.Fn wcstok
79is called,
80.Fa str
81should be specified; subsequent calls, wishing to obtain further tokens
82from the same string, should pass a null pointer instead.
83The separator string,
84.Fa sep ,
85must be supplied each time, and may change between calls.
86The context pointer
87.Fa last
88must be provided on each call.
89.Pp
90The
91.Fn wcstok
92function is the wide-character counterpart of the
93.Xr strtok_r 3
94function.
95.Pp
96Since
97.Fn wcstok
98modifies the string,
99.Fa str
100should not point to an area in the initialized data segment.
101.Sh RETURN VALUES
102The
103.Fn wcstok
104function
105returns a pointer to the beginning of each subsequent token in the string,
106after replacing the token itself with a NUL wide character (L'\e0').
107When no more tokens remain, a null pointer is returned.
108.Sh EXAMPLES
109The following code fragment splits a wide-character string on
110.Tn ASCII
111space, tab, and newline characters and writes the tokens to
112standard output:
113.Bd -literal -offset indent
114const wchar_t *seps = L" \et\en";
115wchar_t *last, *tok, text[] = L" \enone\ettwo\et\etthree  \en";
116
117for (tok = wcstok(text, seps, &last); tok != NULL;
118    tok = wcstok(NULL, seps, &last))
119	wprintf(L"%ls\en", tok);
120.Ed
121.Sh SEE ALSO
122.Xr strtok 3 ,
123.Xr wcschr 3 ,
124.Xr wcscspn 3 ,
125.Xr wcspbrk 3 ,
126.Xr wcsrchr 3 ,
127.Xr wcsspn 3 ,
128.Xr wcsstr 3 ,
129.Xr wmemchr 3
130.Sh STANDARDS
131The
132.Fn wcstok
133function
134conforms to
135.St -isoC-99 .
136.Sh HISTORY
137The
138.Fn wcstok
139function was ported from
140.Nx
141and first appeared in
142.Ox 3.8 .
143.Pp
144Some early implementations of
145.Fn wcstok
146omit the
147context pointer argument,
148.Fa last ,
149and maintain state across calls in a static variable like
150.Xr strtok 3
151does.
152