iscntrl(3) - Manual pages

NAME

iscntrl — control character test

#include <ctype.h>

int
iscntrl(int c);;

The iscntrl() function tests for any control character. In the ASCII character set, this includes the following characters:

000 nul 001\soh 002\stx 003\etx 004\eot

005 enq 006\ack 007\bel 010\bs 011\ht

012 nl 013\vt 014\np 015\cr 016\so

017 si 020\dle 021\dc1 022\dc2 023\dc3

024 dc4 025\nak 026\syn 027\etb 030\can

031 em 032\sub 033\esc 034\fs 035\gs

036 rs 037\us 177\del

The iscntrl() function returns zero if the character tests false and returns non-zero if the character tests true.

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