NAME
iscntrl —
control character test
LIBRARY
library “libc”
SYNOPSIS
#include
<ctype.h>
int
iscntrl(int
c);
DESCRIPTION
Theiscntrl()
function tests for any control character.
RETURN VALUES
The iscntrl() function returns zero if the
character tests false and returns non-zero if the character tests true.
SEE ALSO
ctype(3), isalnum(3), isalpha(3), isascii(3), isblank(3), isdigit(3), isgraph(3), islower(3), isprint(3), ispunct(3), isspace(3), isupper(3), isxdigit(3), stdio(3), toascii(3), tolower(3), toupper(3), ascii(7)
STANDARDS
The iscntrl() function conforms to
ANSI X3.159-1989
(“ANSI C89”).
CAVEATS
The argument to iscntrl() must be
EOF or representable as an unsigned
char; otherwise, the behavior is undefined. See the
CAVEATS section of
ctype(3) for more details.