Xref: utzoo comp.lang.c:12454 comp.std.c:364
Path: utzoo!attcan!uunet!husc6!bloom-beacon!apple!voder!pyramid!ctnews!starfish!cdold
From: cdold@starfish.Convergent.COM (Clarence Dold)
Newsgroups: comp.lang.c,comp.std.c
Subject: Re: Calling functions by address
Message-ID: <707@starfish.Convergent.COM>
Date: 9 Sep 88 17:45:35 GMT
References: <758@goofy.meest.UUCP
Organization: Convergent Technologies, San Jose, CA
Lines: 33


 From article <679@mssx.UUCP>, by src@mssx.UUCP (Pleschutznig Andreas):
> 
> So we thought of doing that job by declaring the addresses of the emulation 
> routines and jumping to the routines by address like this
> 
> 	(*addressarray[code]);
> 
> I know, I know that *does not* work, but maybe there is someone knowing to
> get around.

I don't know about that not working, but this one does work.
For QuickC, running on a PC, jumps to a ROM based routine (actually the 
reset jump for an 8088 CPU chip).
I use this same method to 'wrap' the ROM based disk format that is contained
in BIOS ROM on the controller card with a friendlier menu.

main ()
{
  void (far *bye) ();
  int far *pt;

  pt = ((int far *) (0x0000472L);
  *pt = 0x1234;                    /* for warm boot */
  /*  *pt = 0x0000;  */           /* for cold boot */

  bye = (void far *) 0x0ffff0000L;
  (*bye) ();
}
-- 
Clarence A Dold - cdold@starfish.Convergent.COM		(408) 435-5274
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