4.4BSD snapshot (revision 8.1); add 1993 to copyright
[unix-history] / usr / src / lib / libc / locale / iscntrl.3
.\" Copyright (c) 1991, 1993
.\" The Regents of the University of California. All rights reserved.
.\"
.\" This code is derived from software contributed to Berkeley by
.\" the American National Standards Committee X3, on Information
.\" Processing Systems.
.\"
.\" %sccs.include.redist.man%
.\"
.\" @(#)iscntrl.3 8.1 (Berkeley) %G%
.\"
.Dd
.Dt ISCNTRL 3
.Os
.Sh NAME
.Nm iscntrl
.Nd control character test
.Sh SYNOPSIS
.Fd #include <ctype.h>
.Ft int
.Fn iscntrl "int c";
.Sh DESCRIPTION
The
.Fn iscntrl
function tests for any control character.
In the ASCII character set, this includes the following characters:
.sp
.Bl -column \&000_``0''__ \&000_``0''__ \&000_``0''__ \&000_``0''__ \&000_``0''__
.It \&000\ nul \t001\ soh \t002\ stx \t003\ etx \t004\ eot
.It \&005\ enq \t006\ ack \t007\ bel \t010\ bs \t011\ ht
.It \&012\ nl \t013\ vt \t014\ np \t015\ cr \t016\ so
.It \&017\ si \t020\ dle \t021\ dc1 \t022\ dc2 \t023\ dc3
.It \&024\ dc4 \t025\ nak \t026\ syn \t027\ etb \t030\ can
.It \&031\ em \t032\ sub \t033\ esc \t034\ fs \t035\ gs
.It \&036\ rs \t037\ us \t177\ del
.El
.Sh RETURN VALUES
The
.Fn iscntrl
function returns zero if the character tests false and
returns non-zero if the character tests true.
.Sh SEE ALSO
.Xr ctype 3 ,
.Xr ascii 7
.Sh STANDARDS
The
.Fn iscntrl
function conforms to
.St -ansiC .