ISUPPER(3)

NAME
isupper, isupper_l - upper-case character test

LIBRARY
libc

SYNOPSIS
#include <ctype.h>
int
isupper(int c);
int
isupper_l int c locale_t locale

DESCRIPTION
The isupper() and isupper_l() functions tests 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 _l-suffixed version takes an explicit locale argument, whereas the non-suffixed version uses the current global or per-thread locale.

RETURN VALUES
The isupper() and isupper_l() functions return zero if the character tests false and returns 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() and iswupper_l() functions should be used instead.

SEE ALSO
ctype(3), ctype_l(3), iswupper(3), iswupper_l(3), toupper(3), xlocale(3), ascii(7)

STANDARDS
The isupper() function conforms to isoC. The isupper_l() function conforms to p1003.1-2008.