NAME

       iswupper - test for uppercase wide character

LIBRARY

       Standard C library (libc, -lc)

SYNOPSIS

       #include <wctype.h>

       int iswupper(wint_t wc);

DESCRIPTION

       The  iswupper()  function is the wide-character equivalent of the isupper(3) function.  It
       tests whether wc is a wide character belonging to the wide-character class "upper".

       The wide-character class "upper" is a subclass of the wide-character  class  "alpha",  and
       therefore also a subclass of the wide-character class "alnum", of the wide-character class
       "graph" and of the wide-character class "print".

       Being a subclass of the wide-character class "print", the wide-character class "upper"  is
       disjoint from the wide-character class "cntrl".

       Being  a subclass of the wide-character class "graph", the wide-character class "upper" is
       disjoint from the wide-character class "space" and its subclass "blank".

       Being a subclass of the wide-character class "alnum", the wide-character class "upper"  is
       disjoint from the wide-character class "punct".

       Being  a subclass of the wide-character class "alpha", the wide-character class "upper" is
       disjoint from the wide-character class "digit".

       The wide-character class "upper" contains at least those characters wc which are equal  to
       towupper(wc) and different from towlower(wc).

       The wide-character class "upper" always contains at least the letters 'A' to 'Z'.

RETURN VALUE

       The  iswupper()  function returns nonzero if wc is a wide character belonging to the wide-
       character class "upper".  Otherwise, it returns zero.

ATTRIBUTES

       For an explanation of the terms used in this section, see attributes(7).

       ┌────────────────────────────────────────────────────────┬───────────────┬────────────────┐
       │Interface                                               │ Attribute     │ Value          │
       ├────────────────────────────────────────────────────────┼───────────────┼────────────────┤
       │iswupper()                                              │ Thread safety │ MT-Safe locale │
       └────────────────────────────────────────────────────────┴───────────────┴────────────────┘

STANDARDS

       C11, POSIX.1-2008.

HISTORY

       POSIX.1-2001, C99.

NOTES

       The behavior of iswupper() depends on the LC_CTYPE category of the current locale.

       This function is not very appropriate for dealing with Unicode characters, because Unicode
       knows about three cases: upper, lower, and title case.

SEE ALSO

       isupper(3), iswctype(3), towupper(3)