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.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
4. Neither the name of the University nor the names of its contributors
may be used to endorse or promote products derived from this software
without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.
@(#)iscntrl.3 8.1 (Berkeley) 6/4/93
$FreeBSD$
.Dd July 17, 2005 .Dt ISCNTRL 3 .Os .Sh NAME .Nm iscntrl .Nd control character test .Sh LIBRARY .Lb libc .Sh SYNOPSIS n ctype.h .Ft int .Fn iscntrl "int c" .Ft int .Fn iscntrl_l "int c" "locale_t loc" .Sh DESCRIPTION The .Fn iscntrl function tests for any control character. The value of the argument must be representable as an .Vt "unsigned char" or the value of .Dv EOF .
p In the ASCII character set, this includes the following characters (with their numeric values shown in octal): l -column 000_``0''__ 000_``0''__ 000_``0''__ 000_``0''__ 000_``0''__ t "000 NUL" Ta "001 SOH" Ta "002 STX" Ta "003 ETX" Ta "004 EOT" t "005 ENQ" Ta "006 ACK" Ta "007 BEL" Ta "010 BS" Ta "011 HT" t "012 NL" Ta "013 VT" Ta "014 NP" Ta "015 CR" Ta "016 SO" t "017 SI" Ta "020 DLE" Ta "021 DC1" Ta "022 DC2" Ta "023 DC3" t "024 DC4" Ta "025 NAK" Ta "026 SYN" Ta "027 ETB" Ta "030 CAN" t "031 EM" Ta "032 SUB" Ta "033 ESC" Ta "034 FS" Ta "035 GS" t "036 RS" Ta "037 US" Ta "177 DEL" Ta Ta \& .El
p The .Fn iscntrl_l function takes an explicit locale argument, whereas the .Fn iscntrl function uses the current global or per-thread locale. .Sh RETURN VALUES The .Fn iscntrl function returns zero if the character tests false and returns non-zero if the character tests true. .Sh COMPATIBILITY The x 4.4 extension of accepting arguments outside of the range of the .Vt "unsigned char" type in locales with large character sets is considered obsolete and may not be supported in future releases. The .Fn iswcntrl function should be used instead. .Sh SEE ALSO .Xr ctype 3 , .Xr iswcntrl 3 , .Xr xlocale 3 , .Xr ascii 7 .Sh STANDARDS The .Fn iscntrl function conforms to .St -isoC . The .Fn iscntrl_l function conforms to .St -p1003.1-2008 .