xref: /freebsd/lib/libc/string/wcstok.3 (revision e0c4386e)
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3.\" strtok_r, from Berkeley strtok
4.\" Oct 13, 1998 by Wes Peters <wes@softweyr.com>
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50.Dd October 3, 2002
51.Dt WCSTOK 3
52.Os
53.Sh NAME
54.Nm wcstok
55.Nd split wide-character string into tokens
56.Sh LIBRARY
57.Lb libc
58.Sh SYNOPSIS
59.In wchar.h
60.Ft wchar_t *
61.Fn wcstok "wchar_t * restrict str" "const wchar_t * restrict sep" "wchar_t ** restrict last"
62.Sh DESCRIPTION
63The
64.Fn wcstok
65function
66is used to isolate sequential tokens in a null-terminated wide character
67string,
68.Fa str .
69These tokens are separated in the string by at least one of the
70characters in
71.Fa sep .
72The first time that
73.Fn wcstok
74is called,
75.Fa str
76should be specified; subsequent calls, wishing to obtain further tokens
77from the same string, should pass a null pointer instead.
78The separator string,
79.Fa sep ,
80must be supplied each time, and may change between calls.
81The context pointer
82.Fa last
83must be provided on each call.
84.Pp
85The
86.Fn wcstok
87function is the wide character counterpart of the
88.Fn strtok_r
89function.
90.Sh RETURN VALUES
91The
92.Fn wcstok
93function
94returns a pointer to the beginning of each subsequent token in the string,
95after replacing the token itself with a null wide character (L'\e0').
96When no more tokens remain, a null pointer is returned.
97.Sh EXAMPLES
98The following code fragment splits a wide character string on
99.Tn ASCII
100space, tab and newline characters and writes the tokens to
101standard output:
102.Bd -literal -offset indent
103const wchar_t *seps = L" \et\en";
104wchar_t *last, *tok, text[] = L" \enone\ettwo\et\etthree  \en";
105
106for (tok = wcstok(text, seps, &last); tok != NULL;
107    tok = wcstok(NULL, seps, &last))
108	wprintf(L"%ls\en", tok);
109.Ed
110.Sh COMPATIBILITY
111Some early implementations of
112.Fn wcstok
113omit the
114context pointer argument,
115.Fa last ,
116and maintain state across calls in a static variable like
117.Fn strtok
118does.
119.Sh SEE ALSO
120.Xr strtok 3 ,
121.Xr wcschr 3 ,
122.Xr wcscspn 3 ,
123.Xr wcspbrk 3 ,
124.Xr wcsrchr 3 ,
125.Xr wcsspn 3
126.Sh STANDARDS
127The
128.Fn wcstok
129function
130conforms to
131.St -isoC-99 .
132