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Path: utzoo!mnetor!seismo!rutgers!clyde!cbatt!osu-eddie!bgsuvax!denbeste
From: denbeste@bgsuvax.UUCP (William C. DenBesten)
Newsgroups: comp.sys.apple
Subject: Recovering from ONERR GOTOs
Message-ID: <803@bgsuvax.UUCP>
Date: Fri, 24-Apr-87 08:03:08 EDT
Article-I.D.: bgsuvax.803
Posted: Fri Apr 24 08:03:08 1987
Date-Received: Wed, 29-Apr-87 02:33:09 EDT
References: <8704210236.AA17984@crash.CTS.COM>
Distribution: world
Organization: Bowling Green State University B.G., Oh.
Lines: 21

There is a bug in applesoft that deals with the onerr code.  It deals with the
way the 6502 stack is handled.  This affects the ability of GOSUB/RETURN and
FOR/NEXT to work properly if an ONERR is triggered from within them.  Apple
has published a short assembly language routine that you need to call from
inside your error handler.  It repairs the damage applesoft did to the stack
and allows you to RETURN and NEXT.

Unfortunately, I am at work and my // manuals are at home, but I believe that
the patch is given in the Applesoft manual that I bought for my //e.  It is
also likely to be in the Applesoft manual that came withe the ][+.  Good luck
and happy hunting.

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Wiliam C. DenBesten           |CSNET denbeste@research1.bgsu.edu
Dept of Computer Science      |ARPA  denbeste%research1.bgsu.edu@csnet-relay
Bowling Green State University|UUCP  ...!cbatt!osu-eddie!bgsuvax!denbeste
Bowling Green, OH 43403-0214  |
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