#include <ctype.h> int
isdigit (int c); int
isnumber (int c);
DESCRIPTION
The
isdigit ();
function tests for a decimal digit character.
Regardless of locale, this includes the following characters only:
"``0'' ``1'' ``2'' ``3'' ``4''"
"``5'' ``6'' ``7'' ``8'' ``9''"
The
isnumber ();
function behaves similarly to
isdigit (,);
but may recognize additional characters, depending on the current locale
setting.
The value of the argument must be representable as an
Vt unsigned char
or the value of
EOF
RETURN VALUES
The
isdigit ();
and
isnumber ();
functions return zero if the character tests false and
return 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
iswdigit ();
function should be used instead.
