Path: utzoo!attcan!utgpu!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!cwjcc!gatech!udel!rochester!pt.cs.cmu.edu!b.gp.cs.cmu.edu!Ralf.Brown@B.GP.CS.CMU.EDU
From: Ralf.Brown@B.GP.CS.CMU.EDU
Newsgroups: comp.sys.ibm.pc
Subject: Re: shift-print sreen from  .bat file
Message-ID: <237ae1c0@ralf>
Date: 11 Nov 88 12:49:04 GMT
Sender: ralf@b.gp.cs.cmu.edu
Lines: 23
In-Reply-To: <772@wsccs.UUCP>

In article <772@wsccs.UUCP>, rargyle@wsccs.UUCP (Bob Argyle) writes:
}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.

As a matter of fact, there is ALWAYS a zero on the stack, because DOS pushes
it there just before transferring control to the program.

Actually, both INT 20h and JMP 0 are now officially frowned upon, you should
be using INT 21h/AH=4Ch (but since when has that stopped any programmer?)
--
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claimed something?|   you will recognize yourself as part of the problem.