string/FreeBSD/wcstok.3

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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 .\" $FreeBSD: src/lib/libc/string/wcstok.3,v 1.4 2002/10/15 09:49:54 tjr Exp $
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  52 .Dd October 3, 2002
  53 .Dt WCSTOK 3
  54 .Os
  55 .Sh NAME
  56 .Nm wcstok
  57 .Nd split wide-character string into tokens
  58 .Sh LIBRARY
  59 .Lb libc
  60 .Sh SYNOPSIS
  61 .In wchar.h
  62 .Ft wchar_t *
  63 .Fo wcstok
  64 .Fa "wchar_t *restrict ws1"
  65 .Fa "const wchar_t *restrict ws2"
  66 .Fa "wchar_t **restrict ptr"
  67 .Fc
  68 .Sh DESCRIPTION
  69 The
  70 .Fn wcstok
  71 function
  72 is used to isolate sequential tokens in a null-terminated wide character
  73 string,
  74 .Fa ws1 .
  75 These tokens are separated in the string by at least one of the
  76 characters in
  77 .Fa ws2 .
  78 The first time that
  79 .Fn wcstok
  80 is called,
  81 .Fa ws1
  82 should be specified; subsequent calls, wishing to obtain further tokens
  83 from the same string, should pass a null pointer instead.
  84 The separator string,
  85 .Fa ws2 ,
  86 must be supplied each time, and may change between calls.
  87 The context pointer,
  88 .Fa ptr ,
  89 must be provided on each call.
  90 .Pp
  91 The
  92 .Fn wcstok
  93 function is the wide character counterpart of the
  94 .Fn strtok_r
  95 function.
  96 .Sh RETURN VALUES
  97 The
  98 .Fn wcstok
  99 function
 100 returns a pointer to the beginning of each subsequent token in the string,
 101 after replacing the token itself with a null wide character (L'\e0').
 102 When no more tokens remain, a null pointer is returned.
 103 .Sh EXAMPLES
 104 The following code fragment splits a wide character string on
 105 .Tn ASCII
 106 space, tab, and newline characters,
 107 writing the resulting tokens to standard output:
 108 .Bd -literal -offset indent
 109 const wchar_t *seps = L" \et\en";
 110 wchar_t *last, *tok, text[] = L" \enone\ettwo\et\etthree  \en";
 111
 112 for (tok = wcstok(text, seps, &last); tok != NULL;
 113     tok = wcstok(NULL, seps, &last))
 114         wprintf(L"%ls\en", tok);
 115 .Ed
 116 .Sh COMPATIBILITY
 117 Some early implementations of
 118 .Fn wcstok
 119 omit the
 120 context pointer argument,
 121 .Fa ptr ,
 122 and maintain state across calls in a static variable like
 123 .Fn strtok
 124 does.
 125 .Sh SEE ALSO
 126 .Xr strtok 3 ,
 127 .Xr wcschr 3 ,
 128 .Xr wcscspn 3 ,
 129 .Xr wcspbrk 3 ,
 130 .Xr wcsrchr 3 ,
 131 .Xr wcsspn 3
 132 .Sh STANDARDS
 133 The
 134 .Fn wcstok
 135 function
 136 conforms to
 137 .St -isoC-99 .