iswupper(3)                Library Functions Manual                iswupper(3)

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)

Linux man-pages 6.7               2023-10-31                       iswupper(3)