1.\" Copyright (c) 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software contributed to Berkeley by 5.\" the American National Standards Committee X3, on Information 6.\" Processing Systems. 7.\" 8.\" %sccs.include.redist.man% 9.\" 10.\" @(#)iscntrl.3 8.1 (Berkeley) 06/04/93 11.\" 12.Dd 13.Dt ISCNTRL 3 14.Os 15.Sh NAME 16.Nm iscntrl 17.Nd control character test 18.Sh SYNOPSIS 19.Fd #include <ctype.h> 20.Ft int 21.Fn iscntrl "int c"; 22.Sh DESCRIPTION 23The 24.Fn iscntrl 25function tests for any control character. 26In the ASCII character set, this includes the following characters: 27.sp 28.Bl -column \&000_``0''__ \&000_``0''__ \&000_``0''__ \&000_``0''__ \&000_``0''__ 29.It \&000\ nul \t001\ soh \t002\ stx \t003\ etx \t004\ eot 30.It \&005\ enq \t006\ ack \t007\ bel \t010\ bs \t011\ ht 31.It \&012\ nl \t013\ vt \t014\ np \t015\ cr \t016\ so 32.It \&017\ si \t020\ dle \t021\ dc1 \t022\ dc2 \t023\ dc3 33.It \&024\ dc4 \t025\ nak \t026\ syn \t027\ etb \t030\ can 34.It \&031\ em \t032\ sub \t033\ esc \t034\ fs \t035\ gs 35.It \&036\ rs \t037\ us \t177\ del 36.El 37.Sh RETURN VALUES 38The 39.Fn iscntrl 40function returns zero if the character tests false and 41returns non-zero if the character tests true. 42.Sh SEE ALSO 43.Xr ctype 3 , 44.Xr ascii 7 45.Sh STANDARDS 46The 47.Fn iscntrl 48function conforms to 49.St -ansiC . 50