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Re: machine hacking

A few more hours of persistence paid off here....

You have to make use of the <C-raw-...> types that allow anything goes...


define C-union <DOPPELGANGER>
  slot float-value :: <C-float>;
  slot long-value  :: <C-raw-unsigned-long>;
  array slot uchar-value  :: <C-raw-unsigned-char>, length: 4;
  pointer-type-name: <DOPPELGANGER*>;
end C-union;


define method poke-word (buf :: <simple-vector>,
                         offset :: <integer>,
                         wrd :: <machine-word>)
                     => ()
  let off :: <integer> = 4 * offset;
  with-stack-structure (d :: <DOPPELGANGER*>)
    d.long-value := wrd;
    for(ix :: <integer> from 0 below 4)
      buf[off + ix] := uchar-value(d, ix);
    end;
  end;
end method;


Thanks,

- DM

Chris Double wrote in message ...
>"David McClain" <dmcclain@azstarnet.com> writes:
>
>> The trouble arises because the value #xbadc0db4 can't be converted
>> to <integer> since integers are only 29 bits or so. And I have to
>> coerce the value to something acceptable to storing into a <c-long>
>> value. Type <abstract-integer> doesn't work here, since <c-long>
>> still expects an <integer>.
>
>A similar problem came up a couple of years ago on the newsgroup but
>the solution appears to have vanished off deja.com unfortunately.
>
>Take a look at c-mapped-subtype in the online help. It shows an
>example of converting integers to raw ints, etc. Using something like
>this I think you can do what you want. I'm pretty sure the solution on
>the newsgroup used that in some manner.
>
>Chris.
>--
>http://www.double.co.nz/dylan
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