ISCNTRL(3) |
Library Functions Manual |
ISCNTRL(3) |
iscntrl
—
control character test
Standard C Library (libc, -lc)
#include <ctype.h>
int
iscntrl
(int
c);
The iscntrl
() function tests for any control character.
The iscntrl
() function returns zero if the character
tests false and returns non-zero if the character tests true.
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)
The iscntrl
() function conforms to ANSI
X3.159-1989 (“ANSI C89”).
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.