NAME
isupper
, isupper_l
— upper-case character
test
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include
<ctype.h>
int
isupper
(int
c);
int
isupper_l
(int
c, locale_t
loc);
DESCRIPTION
The
isupper
()
and isupper_l
() functions test for any upper-case
letter. The value of the argument must be representable as an
unsigned char or the value of
EOF
.
In the ASCII character set, this includes the following characters (with their numeric values shown in octal):
101 ``A'' | 102 ``B'' | 103 ``C'' | 104 ``D'' | 105 ``E'' |
106 ``F'' | 107 ``G'' | 110 ``H'' | 111 ``I'' | 112 ``J'' |
113 ``K'' | 114 ``L'' | 115 ``M'' | 116 ``N'' | 117 ``O'' |
120 ``P'' | 121 ``Q'' | 122 ``R'' | 123 ``S'' | 124 ``T'' |
125 ``U'' | 126 ``V'' | 127 ``W'' | 130 ``X'' | 131 ``Y'' |
132 ``Z'' |
The
isupper_l
()
function takes an explicit locale argument, whereas the
isupper
() function uses the current global or
per-thread locale.
RETURN VALUES
The isupper
() and
isupper_l
() functions return zero if the character
tests false and return non-zero if the character tests true.
COMPATIBILITY
The 4.4BSD extension of accepting
arguments outside of the range of the unsigned char
type in locales with large character sets is considered obsolete and may not
be supported in future releases. The iswupper
() or
iswupper_l
() function should be used instead.
SEE ALSO
ctype(3), ctype_l(3), iswupper(3), iswupper_l(3), toupper(3), toupper_l(3), xlocale(3), ascii(7)
STANDARDS
The isupper
() function conforms to
ISO/IEC 9899:1990
(“ISO C90”).
HISTORY
The isupper
() function first appeared in
Version 7 AT&T UNIX.