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ISUPPER(3)                 Library Functions Manual                 ISUPPER(3)

NAME
     isupper - upper-case character test

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <ctype.h>

     int
     isupper(int c);

DESCRIPTION
     The isupper() function tests for any upper-case letter or any of an
     implementation-defined set of characters for which none of iscntrl(3),
     isdigit(3), ispunct(3), or isspace(3) is true.  In the ``C'' locale,
     isupper() returns true only for the characters defined as upper-case
     letters.

RETURN VALUES
     The isupper() function returns zero if the character tests false and
     returns non-zero if the character tests true.

SEE ALSO
     ctype(3), isalnum(3), isalpha(3), isascii(3), isblank(3), iscntrl(3),
     isdigit(3), isgraph(3), islower(3), isprint(3), ispunct(3), isspace(3),
     isxdigit(3), stdio(3), toascii(3), tolower(3), toupper(3), ascii(7)

STANDARDS
     The isupper() function conforms to ANSI X3.159-1989 ("ANSI C89").

CAVEATS
     The argument to isupper() must be EOF or representable as an unsigned
     char; otherwise, the behavior is undefined.  See the CAVEATS section of
     ctype(3) for more details.

NetBSD 10.99                    April 17, 2008                    NetBSD 10.99