NAME

ctype - character classification

SYNOPSIS

#include <ctype_p.h>

int isalpha (c)
int c;

DESCRIPTION

These macros classify ASCII coded integer values by table lookup. Each is a predicate returning nonzero for true, zero for false. isascii is defined on all integer values; the rest are defined only when isascii is true and on the single non-ASCII value EOF (see stdio(3P) ).

isalpha
c is a letter

isupper
c is an upper case letter

islower
c is a lower case letter

isdigit
c is a digit [0-9]

isxdigit
c is a hexadecimal digit [0-9], [A-F] or [a-f]

isalnum
c is an alphanumeric

isspace
c is a space, tab, carraige return, new-line, vertical tab, or form-feed

ispunct
c is a punctuation character (neither control nor alphanumeric)

isprint
c is a printing character, code 040 (space) through 0176 (tilde)

isgraph
c is a printing character, like 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