Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!bbn!apple!chuq
From: chuq@Apple.COM (Chuq Von Rospach)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Program immunization
Message-ID: <27718@apple.Apple.COM>
Date: 22 Mar 89 19:05:40 GMT
References: <1780@psu-cs.UUCP>
Distribution: usa
Organization: Life is just a Fantasy novel played for keeps
Lines: 26

>	This may not be such a new idea, but i think merits some discussion.
>In writing  programs, do the following to the release versions:

>1. Make a procedure which on startup checks the size of the program and 
>determines if it is equal to a constant

>	Of course i'm assuming that the program is not self modifying

Worse. It means that you can't internationalize the program for other
languages. It means that people can't go in and relocate or change the size
of dialogs, or add/modify keyboard definitions, or even add "Get Info" data.

I *do* think it is a good idea (in theory) for a program to do a consistency
check on itself -- verify that critical resources exist and perhaps checksum
CODE resources that don't change. But trying to verify the entire package
removes all of the advantages of having resources -- to change things, you
have to recompile the checksumming routines.


Chuq Von Rospach       -*-      Editor,OtherRealms      -*-      Member SFWA
chuq@apple.com  -*-  CI$: 73317,635  -*-  Delphi: CHUQ  -*-  Applelink: CHUQ
      [This is myself speaking. No company can control my thoughts.]

USENET: N. A self-replicating phage engineered by the phone company to cause
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