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`isprint', `isgraph'--printable character predicates

     #include <ctype.h>
     int isprint(int C);
     int isgraph(int C);
`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''.
`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.
`isprint' and `isgraph' are ANSI C.
   No supporting OS subroutines are required.