urlichs@smurf.ira.uka.de (Matthias Urlichs) (02/08/89)
In comp.sys.mac sebruun@ihlpa.ATT.COM (Bruun) writes: < In article <19788@agate.BERKELEY.EDU>, steve@violet.berkeley.edu (Steve Goldfield) writes: < > < > [ list of INITs/programs and their sizes deleted ] < < This brings up a question I've wondered about: How many bytes represent < a significant difference between two theoretically equivalent files? I'm < [...] < My question stems from the discrepancies in the sizes of various copies < of the same version of some of the DAs, particularly the Control Panel < and Chooser. Sometimes these differences are on the order of 1K or even < more. Why? [...] < Both Chooser and Control Panel store their devices' icons along with the actual DA (in the System usually) so as to save time when opening. (They don't want to open every one of these resource files -- takes time.) < In general, then, to what extent can the number of bytes occupied by a < file be used to determine whether it is truly different from another? This is a problem. It will become more of a problem when the first virus kills off part of a program to install itself inside. Fortunately, as far as I know, there's no such beast as of now. < Is there a better way? < There's a program called ResLister (or something like that) which lists which resources are in a file, how big they are, and what checksum they have. Unfortunately I'm writing this under A/UX 1.0, so ResList is far, far away... -- Matthias Urlichs -- Humboldtstrasse 7 -- 7500 Karlsruhe 1 -- FRG urlichs@smurf.ira.uka.de -- ++49+721-621127@PTT