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 .Fn wcstok "wchar_t * restrict str" "const wchar_t * restrict sep" "wchar_t ** restrict last"
  64 .Sh DESCRIPTION
  65 The
  66 .Fn wcstok
  67 function
  68 is used to isolate sequential tokens in a null-terminated wide character
  69 string,
  70 .Fa str .
  71 These tokens are separated in the string by at least one of the
  72 characters in
  73 .Fa sep .
  74 The first time that
  75 .Fn wcstok
  76 is called,
  77 .Fa str
  78 should be specified; subsequent calls, wishing to obtain further tokens
  79 from the same string, should pass a null pointer instead.
  80 The separator string,
  81 .Fa sep ,
  82 must be supplied each time, and may change between calls.
  83 The context pointer
  84 .Fa last
  85 must be provided on each call.
  86 .Pp
  87 The
  88 .Fn wcstok
  89 function is the wide character counterpart of the
  90 .Fn strtok_r
  91 function.
  92 .Sh RETURN VALUES
  93 The
  94 .Fn wcstok
  95 function
  96 returns a pointer to the beginning of each subsequent token in the string,
  97 after replacing the token itself with a null wide character (L'\e0').
  98 When no more tokens remain, a null pointer is returned.
  99 .Sh EXAMPLES
 100 The following code fragment splits a wide character string on
 101 .Tn ASCII
 102 space, tab and newline characters and writes the tokens to
 103 standard output:
 104 .Bd -literal -offset indent
 105 const wchar_t *seps = L" \et\en";
 106 wchar_t *last, *tok, text[] = L" \enone\ettwo\et\etthree  \en";
 107
 108 for (tok = wcstok(text, seps, &last); tok != NULL;
 109     tok = wcstok(NULL, seps, &last))
 110         wprintf(L"%ls\en", tok);
 111 .Ed
 112 .Sh COMPATIBILITY
 113 Some early implementations of
 114 .Fn wcstok
 115 omit the
 116 context pointer argument,
 117 .Fa last ,
 118 and maintain state across calls in a static variable like
 119 .Fn strtok
 120 does.
 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 .Sh STANDARDS
 129 The
 130 .Fn wcstok
 131 function
 132 conforms to
 133 .St -isoC-99 .