man3/iswcntrl.3

   1 .\" Copyright (c) Bruno Haible <haible@clisp.cons.org>
   2 .\"
   3 .\" SPDX-License-Identifier: GPL-2.0-or-later
   4 .\"
   5 .\" References consulted:
   6 .\"   GNU glibc-2 source code and manual
   7 .\"   Dinkumware C library reference http://www.dinkumware.com/
   8 .\"   OpenGroup's Single UNIX specification http://www.UNIX-systems.org/online.html
   9 .\"   ISO/IEC 9899:1999
  10 .\"
  11 .TH ISWCNTRL 3  2021-03-22 "Linux man-pages (unreleased)" "Linux Programmer's Manual"
  12 .SH NAME
  13 iswcntrl \- test for control wide character
  14 .SH LIBRARY
  15 Standard C library
  16 .RI ( libc ", " \-lc )
  17 .SH SYNOPSIS
  18 .nf
  19 .B #include <wctype.h>
  20 .PP
  21 .BI "int iswcntrl(wint_t " wc );
  22 .fi
  23 .SH DESCRIPTION
  24 The
  25 .BR iswcntrl ()
  26 function is the wide-character equivalent of the
  27 .BR iscntrl (3)
  28 function.
  29 It tests whether
  30 .I wc
  31 is a wide character
  32 belonging to the wide-character class "cntrl".
  33 .PP
  34 The wide-character class "cntrl" is disjoint from the wide-character class
  35 "print" and therefore also disjoint from its subclasses "graph", "alpha",
  36 "upper", "lower", "digit", "xdigit", "punct".
  37 .PP
  38 For an unsigned char
  39 .IR c ,
  40 .I iscntrl(c)
  41 implies
  42 .IR iswcntrl(btowc(c)) ,
  43 but not vice versa.
  44 .SH RETURN VALUE
  45 The
  46 .BR iswcntrl ()
  47 function returns nonzero if
  48 .I wc
  49 is a
  50 wide character belonging to the wide-character class "cntrl".
  51 Otherwise, it returns zero.
  52 .SH ATTRIBUTES
  53 For an explanation of the terms used in this section, see
  54 .BR attributes (7).
  55 .ad l
  56 .nh
  57 .TS
  58 allbox;
  59 lbx lb lb
  60 l l l.
  61 Interface       Attribute       Value
  62 T{
  63 .BR iswcntrl ()
  64 T}      Thread safety   MT-Safe locale
  65 .TE
  66 .hy
  67 .ad
  68 .sp 1
  69 .SH STANDARDS
  70 POSIX.1-2001, POSIX.1-2008, C99.
  71 .SH NOTES
  72 The behavior of
  73 .BR iswcntrl ()
  74 depends on the
  75 .B LC_CTYPE
  76 category of the
  77 current locale.
  78 .SH SEE ALSO
  79 .BR iscntrl (3),
  80 .BR iswctype (3)