man3/iswupper.3

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   2 .\" Copyright (c) Bruno Haible <haible@clisp.cons.org>
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   6 .\" References consulted:
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   9 .\"   OpenGroup's Single UNIX specification http://www.UNIX-systems.org/online.html
  10 .\"   ISO/IEC 9899:1999
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  12 .TH iswupper 3 (date) "Linux man-pages (unreleased)"
  13 .SH NAME
  14 iswupper \- test for uppercase 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 iswupper(wint_t " wc );
  23 .fi
  24 .SH DESCRIPTION
  25 The
  26 .BR iswupper ()
  27 function is the wide-character equivalent of the
  28 .BR isupper (3)
  29 function.
  30 It tests whether
  31 .I wc
  32 is a wide character
  33 belonging to the wide-character class "upper".
  34 .PP
  35 The wide-character class "upper" is a subclass of the wide-character class
  36 "alpha", and therefore also a subclass of the wide-character class "alnum", of
  37 the wide-character class "graph" and of the wide-character class "print".
  38 .PP
  39 Being a subclass of the wide-character class "print", the wide-character class
  40 "upper" is disjoint from the wide-character class "cntrl".
  41 .PP
  42 Being a subclass of the wide-character class "graph", the wide-character class
  43 "upper" is disjoint from the wide-character class "space" and its subclass
  44 "blank".
  45 .PP
  46 Being a subclass of the wide-character class "alnum", the wide-character class
  47 "upper" is disjoint from the wide-character class "punct".
  48 .PP
  49 Being a subclass of the wide-character class "alpha", the wide-character class
  50 "upper" is disjoint from the wide-character class "digit".
  51 .PP
  52 The wide-character class "upper" contains at least those characters
  53 .I wc
  54 which are equal to
  55 .I towupper(wc)
  56 and different from
  57 .IR towlower(wc) .
  58 .PP
  59 The wide-character class "upper" always contains at least the
  60 letters \(aqA\(aq to \(aqZ\(aq.
  61 .SH RETURN VALUE
  62 The
  63 .BR iswupper ()
  64 function returns nonzero if
  65 .I wc
  66 is a wide character
  67 belonging to the wide-character class "upper".
  68 Otherwise, it returns zero.
  69 .SH ATTRIBUTES
  70 For an explanation of the terms used in this section, see
  71 .BR attributes (7).
  72 .ad l
  73 .nh
  74 .TS
  75 allbox;
  76 lbx lb lb
  77 l l l.
  78 Interface       Attribute       Value
  79 T{
  80 .BR iswupper ()
  81 T}      Thread safety   MT-Safe locale
  82 .TE
  83 .hy
  84 .ad
  85 .sp 1
  86 .SH STANDARDS
  87 POSIX.1-2001, POSIX.1-2008, C99.
  88 .SH NOTES
  89 The behavior of
  90 .BR iswupper ()
  91 depends on the
  92 .B LC_CTYPE
  93 category of the
  94 current locale.
  95 .PP
  96 This function is not very appropriate for dealing with Unicode characters,
  97 because Unicode knows about three cases: upper, lower, and title case.
  98 .SH SEE ALSO
  99 .BR isupper (3),
 100 .BR iswctype (3),
 101 .BR towupper (3)