man3/iswblank.3

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   2 .\" Copyright (c) Bruno Haible <haible@clisp.cons.org>
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   4 .\" SPDX-License-Identifier: GPL-2.0-or-later
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   6 .\" References consulted:
   7 .\"   GNU glibc-2 source code and manual
   8 .\"   Dinkumware C library reference http://www.dinkumware.com/
   9 .\"   OpenGroup's Single UNIX specification http://www.UNIX-systems.org/online.html
  10 .\"   ISO/IEC 9899:1999
  11 .\"
  12 .TH iswblank 3 (date) "Linux man-pages (unreleased)"
  13 .SH NAME
  14 iswblank \- test for whitespace wide character
  15 .SH LIBRARY
  16 Standard C library
  17 .RI ( libc ", " \-lc )
  18 .SH SYNOPSIS
  19 .nf
  20 .B #include <wctype.h>
  21 .PP
  22 .BI "int iswblank(wint_t " wc );
  23 .fi
  24 .PP
  25 .RS -4
  26 Feature Test Macro Requirements for glibc (see
  27 .BR feature_test_macros (7)):
  28 .RE
  29 .PP
  30 .BR iswblank ():
  31 .nf
  32     _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
  33 .fi
  34 .SH DESCRIPTION
  35 The
  36 .BR iswblank ()
  37 function is the wide-character equivalent of the
  38 .BR isblank (3)
  39 function.
  40 It tests whether \fIwc\fP is a wide character
  41 belonging to the wide-character class "blank".
  42 .PP
  43 The wide-character class "blank" is a subclass of the wide-character class
  44 "space".
  45 .PP
  46 Being a subclass of the wide-character class "space",
  47 the wide-character class "blank" is disjoint from the
  48 wide-character class "graph" and therefore also disjoint
  49 from its subclasses "alnum", "alpha", "upper", "lower", "digit",
  50 "xdigit", "punct".
  51 .PP
  52 The wide-character class "blank" always contains
  53 at least the space character
  54 and the control character \[aq]\et\[aq].
  55 .SH RETURN VALUE
  56 The
  57 .BR iswblank ()
  58 function returns nonzero
  59 if \fIwc\fP is a wide character
  60 belonging to the wide-character class "blank".
  61 Otherwise, it returns zero.
  62 .SH ATTRIBUTES
  63 For an explanation of the terms used in this section, see
  64 .BR attributes (7).
  65 .ad l
  66 .nh
  67 .TS
  68 allbox;
  69 lbx lb lb
  70 l l l.
  71 Interface       Attribute       Value
  72 T{
  73 .BR iswblank ()
  74 T}      Thread safety   MT-Safe locale
  75 .TE
  76 .hy
  77 .ad
  78 .sp 1
  79 .SH STANDARDS
  80 POSIX.1-2008.
  81 .SH HISTORY
  82 POSIX.1-2001.
  83 .SH NOTES
  84 The behavior of
  85 .BR iswblank ()
  86 depends on the
  87 .B LC_CTYPE
  88 category of the
  89 current locale.
  90 .SH SEE ALSO
  91 .BR isblank (3),
  92 .BR iswctype (3)