iswupper

ISWUPPER(3)                 Linux Programmer's Manual                ISWUPPER(3)



NAME
       iswupper - test for uppercase wide character

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 │
       └───────────────────────────────────────┴───────────────┴────────────────┘

CONFORMING TO
       POSIX.1-2001, POSIX.1-2008, 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)

COLOPHON
       This page is part of release 5.13 of the Linux man-pages project.  A
       description of the project, information about reporting bugs, and the
       latest version of this page, can be found at
       https://www.kernel.org/doc/man-pages/.



GNU                                2021-03-22                        ISWUPPER(3)