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`toascii'--force integers to ASCII range

     #include <ctype.h>
     int toascii(int C);
`toascii' is a macro which coerces integers to the ASCII range (0-127)
by zeroing any higher-order bits.
   You can use a compiled subroutine instead of the macro definition by
undefining this macro using ``#undef toascii''.
`toascii' returns integers between 0 and 127.
`toascii' is not ANSI C.
   No supporting OS subroutines are required.