NAME
iscntrl —
control character test
SYNOPSIS
#include
<ctype.h>
int
iscntrl(int
c);
DESCRIPTION
The
iscntrl()
function tests for any control character.
RETURN VALUES
The iscntrl() function returns zero if the
character tests false or non-zero if the character tests true.
SEE ALSO
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”).
HISTORY
The iscntrl() function first appeared in
Version 7 AT&T UNIX.
CAVEATS
The argument to iscntrl() must be
EOF or representable as an unsigned
char; otherwise, the result is undefined.