Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!usc!zaphod.mps.ohio-state.edu!rpi!ispd-newsserver!hoffmann
From: hoffmann@acl.kodak.com (marty hoffmann)
Newsgroups: comp.sys.amiga.programmer
Subject: RE: Need a helping hand(ler)
Message-ID: <1991Feb4.143807.4658@ssd.kodak.com>
Date: 4 Feb 91 14:38:07 GMT
Sender: news@ssd.kodak.com
Distribution: usa
Organization: Eastman Kodak
Lines: 37
Originator: hoffmann@acl

I posted a note about trouble I've been having writing
an event handler for the input device.  From the number
of replies I've received (0), I conclude:

	1) My message never got out

	2) It got out, but no one cared :^(
	
	3) No one could figure out what I was talking
	   about

Anyway, I figured it out (All I had to do was RTFM).

SAS C (and possible Lattice V5.0) doesn't automatically
reload A4 with the base address of your data hunk when
you enter a function (unless you ask it to with the
-y option on the compile).

When the input handler called my handler, I went 
and trashed memory in its address space.  The solution
was to use "-y".  Global variables will be my undoing :^)

While reading the manual, I also found a way to get
rid of the assembly code needed to call my handler.
I just declared it:

struct InputEvent * __interrupt __asm
	myhandler (register __a0 struct InputEvent *ev,
		   register __a1 struct MemEntry   *mydata[])
{
...
}

NEAT!  Of course, __interrupt doesn't do anything, but
maybe someday...

						MRH