NAME

isspace — whitespace character test

SYNOPSIS

#include <ctype.h>

int
isspace(int c);

DESCRIPTION

The isspace() function tests for the standard whitespace characters for which isalnum(3) is false. The standard whitespace characters are the following:

In the C locale, isspace() returns true only for the standard whitespace characters.

RETURN VALUES

The isspace() function returns zero if the character tests false or non-zero if the character tests true.

SEE ALSO

isalnum(3), isalpha(3), isascii(3), isblank(3), iscntrl(3), isdigit(3), isgraph(3), islower(3), isprint(3), ispunct(3), isupper(3), isxdigit(3), stdio(3), toascii(3), tolower(3), toupper(3), ascii(7)

STANDARDS

The isspace() function conforms to ANSI X3.159-1989 (“ANSI C89”).

HISTORY

The isspace() function first appeared in Version 7 AT&T UNIX.

CAVEATS

The argument to isspace() must be EOF or representable as an unsigned char; otherwise, the result is undefined.