man3/iswlower.3

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  10 .\" References consulted:
  11 .\"   GNU glibc-2 source code and manual
  12 .\"   Dinkumware C library reference http://www.dinkumware.com/
  13 .\"   OpenGroup's Single UNIX specification http://www.UNIX-systems.org/online.html
  14 .\"   ISO/IEC 9899:1999
  15 .\"
  16 .TH ISWLOWER 3  2015-08-08 "GNU" "Linux Programmer's Manual"
  17 .SH NAME
  18 iswlower \- test for lowercase wide character
  19 .SH SYNOPSIS
  20 .nf
  21 .B #include <wctype.h>
  22 .sp
  23 .BI "int iswlower(wint_t " wc );
  24 .fi
  25 .SH DESCRIPTION
  26 The
  27 .BR iswlower ()
  28 function is the wide-character equivalent of the
  29 .BR islower (3)
  30 function.
  31 It tests whether
  32 .I wc
  33 is a wide character
  34 belonging to the wide-character class "lower".
  35 .PP
  36 The wide-character class "lower" is a subclass of the wide-character class
  37 "alpha", and therefore also a subclass
  38 of the wide-character class "alnum", of
  39 the wide-character class "graph" and of the wide-character class "print".
  40 .PP
  41 Being a subclass of the wide-character class "print",
  42 the wide-character class
  43 "lower" is disjoint from the wide-character class "cntrl".
  44 .PP
  45 Being a subclass of the wide-character class "graph",
  46 the wide-character class "lower" is disjoint from the
  47 wide-character class "space" and its subclass "blank".
  48 .PP
  49 Being a subclass of the wide-character class "alnum",
  50 the wide-character class
  51 "lower" is disjoint from the wide-character class "punct".
  52 .PP
  53 Being a subclass of the wide-character class "alpha",
  54 the wide-character class
  55 "lower" is disjoint from the wide-character class "digit".
  56 .PP
  57 The wide-character class "lower" contains at least
  58 those characters
  59 .I wc
  60 which are equal to
  61 .I towlower(wc)
  62 and different from
  63 .IR towupper(wc) .
  64 .PP
  65 The wide-character class "lower" always contains
  66 at least the letters \(aqa\(aq to \(aqz\(aq.
  67 .SH RETURN VALUE
  68 The
  69 .BR iswlower ()
  70 function returns nonzero
  71 if
  72 .I wc
  73 is a wide character
  74 belonging to the wide-character class "lower".
  75 Otherwise, it returns zero.
  76 .SH ATTRIBUTES
  77 For an explanation of the terms used in this section, see
  78 .BR attributes (7).
  79 .TS
  80 allbox;
  81 lb lb lb
  82 l l l.
  83 Interface       Attribute       Value
  84 T{
  85 .BR iswlower ()
  86 T}      Thread safety   MT-Safe locale
  87 .TE
  88 .SH CONFORMING TO
  89 POSIX.1-2001, POSIX.1-2008, C99.
  90 .SH NOTES
  91 The behavior of
  92 .BR iswlower ()
  93 depends on the
  94 .B LC_CTYPE
  95 category of the
  96 current locale.
  97 .PP
  98 This function is not very appropriate for dealing with Unicode characters,
  99 because Unicode knows about three cases: upper, lower and title case.
 100 .SH SEE ALSO
 101 .BR islower (3),
 102 .BR iswctype (3),
 103 .BR towlower (3)