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 function. It tests whether wc is a wide char-
acter 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 differ-
ent from towlower(wc).
The wide character class "upper" always contains at least
the letters 'A' to 'Z'.
RETURN VALUE
The iswupper function returns non-zero if wc is a wide
character belonging to the wide character class "upper".
Otherwise it returns zero.
CONFORMING TO
ISO/ANSI C, UNIX98
SEE ALSO
isupper(3), iswctype(3), towupper(3)
NOTES
The behaviour of iswupper depends on the LC_CTYPE category
GNU July 25, 1999 1
ISWUPPER(3) Linux Programmer's Manual ISWUPPER(3)
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.
GNU July 25, 1999 2