NAME
ctype, isalpha, isupper, islower, isdigit, isxdigit, isal-
num, isspace, ispunct, isprint, isgraph, iscntrl, isascii,
toupper, tolower, toascii - character classification macros
SYNOPSIS
#include <ctype.h>
int isalpha(int c)
...
DESCRIPTION
These macros classify characters by table lookup. Each is a
predicate returning nonzero for true, zero for false.
Isascii and toascii are defined on all integer values; the
rest are defined only on the range of unsigned char and on
the special value EOF (see stdio(3)).
isalpha c is a letter
isupper c is an upper case letter
islower c is a lower case letter
isdigit c is a digit
isxdigit c is a hex digit
isalnum c is an alphanumeric character
isspace c is a space, tab, carriage return, newline,
vertical tab, or formfeed
ispunct c is a punctuation character (neither control
nor alphanumeric)
isprint c is a printing character, code 040(8)
(space) through 0176 (tilde)
isgraph c is a printing character, similar to isprint
except false for space.
iscntrl c is a delete character (0177) or ordinary
control character (less than 040).
isascii c is an ASCII character, code less than 0200
tolower c is converted to lower case. Return value
is undefined if not isupper(c).
toupper c is converted to upper case. Return value
is undefined if not islower(c).
toascii c is converted to be a valid ascii character.
SEE ALSO
ascii(7)