pgn@osupyr.UUCP (03/20/87)
Why? Why? Why? Do this: install MacsBug or something equivalent. Run MacWrite 4.5. Hit the interrupt switch. Then try to resume or go to the Finder. I can't. Can you? Why? OR Do this: make a simple FKey doing nothing but ExitToShell. Use it on MacWrite 4.5 (or Excel). BOMBBBBB!. Why? So far I couldn't reproduce this on other programs. Paul Nevai pgn%osupyr.uucp (PREFERRED) Department of Mathematics nevai-p@osu-eddie.uucp The Ohio State University ...!ihnp4!cbatt!osupyr!pgn 231 West Eighteenth Avenue TS1171@OHSTVMA.bitnet Columbus, OH 43210, U.S.A. 1-614-292-5688
dgold@apple.UUCP (03/23/87)
In article <121@osupyr.UUCP> pgn@.UUCP (Paul G. Nevai) writes: >Do this: install MacsBug or something equivalent. Run MacWrite 4.5. Hit the >interrupt switch. Then try to resume or go to the Finder. I can't. Can you? >Do this: make a simple FKey doing nothing but ExitToShell. Use it on >MacWrite 4.5 (or Excel). BOMBBBBB!. Why? I've never had any problem entering Macsbug in either of these programs and the continuing. Perhaps you have a bad version of Macsbug. As far as not being able to ExitToShell, it's possible that MacWrite patches some traps (I know Excel does). If they do not patch out ExitToShell in order to clean up their patches if the program exits abnormally, then you will return to the Finder with those patches installed. Since they point into the middle of the now-reinitialized application heap, the first time the Finder calls one of those traps it will bomb. -- David Goldsmith Apple Computer, Inc. MacApp Group AppleLink: GOLDSMITH1 UUCP: {nsc,dual,sun,voder,ucbvax!mtxinu}!apple!dgold CSNET: dgold@apple.CSNET, dgold%apple@CSNET-RELAY BIX: dgoldsmith
rs4u#@ANDREW.CMU.EDU.UUCP (03/23/87)
I haven't tried that with MacsBug, but when I was writing my Transfer... desk accessory, I found that MacWrite would crash miserably when I tried to transfer out of it. This probably has something to do with the way that MacWrite screws around with the trap vectors or interrupt vectors or whatever it is that MacWrite screws around with.... --Rich Richard M. Seigel Mail Stop 231 NASA/Langley Research Center Hampton, Va. 23665 (804) 865-3036
pgn@osupyr.UUCP.UUCP (03/24/87)
My simple FKEY doing nothing but ExitToShell explodes on MacWrite, Word and Excel. Do you think that they could all be guilty and I am innocent? Just try that FKey, takes 5 minutes to write it on LSP. Otherwise, much more complex FKeys work just fine on other programs. Thanks for your comments. Paul Paul Nevai pgn%osupyr.uucp (PREFERRED) Department of Mathematics nevai-p@osu-eddie.uucp The Ohio State University ...!ihnp4!cbatt!osupyr!pgn 231 West Eighteenth Avenue TS1171@OHSTVMA.bitnet Columbus, OH 43210, U.S.A. 1-614-292-5688
dgold@apple.UUCP (03/31/87)
In article <8703232111.AA11200@osupyr.UUCP> pgn@osupyr.UUCP (Paul G. Nevai) writes: >My simple FKEY doing nothing but ExitToShell explodes on MacWrite, Word and >Excel. Do you think that they could all be guilty and I am innocent? Just >try that FKey, takes 5 minutes to write it on LSP. I believe all of these programs patch Mac ROM traps. If you simply ExitToShell, the program does not get a chance to clean up and the patches are left in (there are more serious problems with MacWrite, as it will leave all of its work files open). Since the patches are still there, and point at nonexistent application code (since you've left the application), anyone who calls those traps (like the Finder) will jump off into garbage, with predictable results. In general, it is NOT SAFE to call ExitToShell behind an application's back, and there is no guarantee that it will work. Some applications which patch traps also patch ExitToShell, so that during debugging, if a crash occurs, you can ExitToShell in Macsbug. The ExitToShell patch cleans up the other patches, then exits. -- David Goldsmith Apple Computer, Inc. MacApp Group AppleLink: GOLDSMITH1 UUCP: {nsc,dual,sun,voder,ucbvax!mtxinu}!apple!dgold CSNET: dgold@apple.CSNET, dgold%apple@CSNET-RELAY BIX: dgoldsmith