The
iscntrl ();
function tests for any control character.
The value of the argument must be representable as an
Vt unsigned char
or the value of
EOF
In the ASCII character set, this includes the following characters
(with their numeric values shown in octal):
"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"
RETURN VALUES
The
iscntrl ();
function returns zero if the character tests false and
returns non-zero if the character tests true.
COMPATIBILITY
The
BSD 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
iswcntrl ();
function should be used instead.
