Path: utzoo!attcan!uunet!husc6!bloom-beacon!apple!bionet!agate!helios.ee.lbl.gov!lll-tis!oodis01!uplherc!sp7040!obie!wsccs!rargyle
From: rargyle@wsccs.UUCP (Bob Argyle)
Newsgroups: comp.sys.ibm.pc
Subject: Re: shift-print sreen from  .bat file
Summary: how to get out of a program!
Message-ID: <772@wsccs.UUCP>
Date: 9 Nov 88 16:27:29 GMT
References: <421@caldwr.UUCP> <394@megatek.UUCP>
Lines: 17

In article <394@megatek.UUCP>, hollen@spot.megatek.uucp (Dion Hollenbeck) writes:
> A> debug <CR>
> - A100 <CR>				assemble at location 100
> xxxx:0100   INT 5 <CR>			software interrupt 5
> xxxx:0102   RET <CR>			program return

this is a very good way to lose control of the machine:  what is on the
stack to return to? NOTHING!  
use INT 20 instead of RET, or JMP 0 if you don't want to be
'obsolescent' (it's MS-DOS we're talking here, not OS/2); if there is 
BY CHANCE a zero on the stack then the above code will work.  Not the
sort of thing to depend on.
-- 
                              Bob Argyle @ wsccs
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