isprint, isgraph—printable character predicates #include <ctype.h>
int isprint(int c);
int isgraph(int c);
Description
isprint is a macro which classifies ASCII integer values by table
lookup. It is a predicate returning non-zero for printable
characters, and 0 for other character arguments.
It is defined only when isascii(c) is true or c is EOF.
You can use a compiled subroutine instead of the macro definition by
undefining either macro using `#undef isprint' or `#undef isgraph'.
Returns
isprint returns non-zero if c is a printing character,
(0x20–0x7E).
isgraph behaves identically to isprint, except that the space
character (0x20) is excluded.
Portability
isprint and isgraph are ANSI C.
No supporting OS subroutines are required.