CTYPE(3C) — HP-UX
NAME
isalpha, isupper, islower, isdigit, isxdigit, isalnum, isspace, ispunct, isprint, isgraph, iscntrl, isascii − classify characters
SYNOPSIS
#include <ctype.h>
int isalpha (c)
int c;
. . .
DESCRIPTION
These macros classify character-coded integer values according to the rules of the coded character set identified by the last successful call to nl_init(3C). Each macro is a predicate returning non-zero for true, zero for false.
If nl_init(3C) has not been called successfully, characters are classified according to the rules of the default ASCII 7-bit coded character set (see nl_init(3C)).
Isascii is defined on all integer values; the other macros are defined for the range −1 (EOF) to 255.
isalpha c is a letter.
isupper c is an uppercase letter.
islower c is a lowercase letter.
isdigit c is a decimal digit (in ASCII: characters [0-9]).
isxdigit c is a hexadecimal digit (in ASCII: characters [0-9], [A-F] or [a-f]).
isalnum c is an alphanumeric (letters or digits).
isspace c is a character that creates "white space" in displayed text (in ASCII: space, tab, carriage return, new-line, vertical tab, and form-feed).
ispunct c is a punctuation character (in ASCII: any printing character except the space character (040), digits, letters).
isprint c is a printing character.
isgraph c is a visible character (in ASCII: printing characters, excluding the space character (040)).
iscntrl c is a control character (in ASCII: character codes less than 040 and the delete character (0177)).
isascii c is any ASCII character code between 0 and 0177, inclusive.
DIAGNOSTICS
If the argument to any of these macros is outside the domain of the function, the result is undefined.
AUTHOR
Ctype was developed by AT&T and HP.
HARDWARE DEPENDENCIES
Series 200, 300, 500
Characters are classified according to the rules of the default ASCII 7-bit coded character set because nl_init(3C) is not currently supported. For NLS, use the routines described in nl_ctype(3C) instead.
SEE ALSO
nl_init(3C), stdio(3S), ascii(5).
INTERNATIONAL SUPPORT
8-bit data.
Hewlett-Packard Company — Version B.1, May 11, 2021