ISASCII(3) Library Functions Manual ISASCII(3)

isasciitest for ASCII character

Standard C Library (libc, -lc)

#include <ctype.h>

int
isascii(int c);

The () function tests for an ASCII character, which is any character between 0 and octal 0177 inclusive.

ctype(3), iswascii(3), ascii(7)

October 6, 2002 macOS 15.2