Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!zaphod.mps.ohio-state.edu!unix.cis.pitt.edu!dsinc!netnews.upenn.edu!vax1.cc.lehigh.edu!cert.sei.cmu.edu!krvw From: well!odawa@apple.com (Michael Odawa) Newsgroups: comp.virus Subject: re: Mac virus question (Mac) Message-ID: <0001.9011141856.AA23262@ubu.cert.sei.cmu.edu> Date: 8 Nov 90 20:02:32 GMT Sender: Virus Discussion List Lines: 68 Approved: krvw@sei.cmu.edu > In Virus-L 3:181, Joe McMahon writes, >> From: "Terry (TR) Roebuck; 966-4841" >> there were at least 4 different versions of the system on the disk... > This is *extremely* bad thing number 2. Doing this kind of thing > almost guarantees that sooner or later the Resource Manager is going > to get confused and start loading from the wrong System file... Joe is correct in his conclusion, though he reflects a common misunderstanding about the Mac. There is nothing in the Macintosh operating system itself that precludes multiple system files on a single disk. I have five on mine right now. The Resource Manager never gets confused, nor do any of the other O.S. or application software facilities. It's all very clear on the inside of the machine. What _is_ problematic about multiple system files is that it's extremely difficult for the _human operators_ to keep track of which is the "real" System file, without careful and deliberate management procedures. Some resources such as fonts, INITs, application preferences, etc., therefore get thrown into the "wrong" system folder, yielding a performance profile at variance from what the user expects. Therefore Joe is correct in recommending against multiple system files. I'd like to extend this warning by offering the following procedures for managing the Macintosh System file. 1. Always keep the System Folder in the lower-left corner of the boot disk's desktop. Just as maps normally put North at the top, it's useful to have a convention, and the lower-left corner is both common among other users and aesthetic to the eye. 2. Never keep more than one System file on a single disk, unless there is a strong and persuasive reason to do so. 3. If there _is_ reason to keep multiple System files, every such file should be kept in a separate folder which contains the complete set of system files (i.e., Finder, System, print drivers, etc.) for that version. Each of these versions will be a separate operating environment, so keep a separate copy of your favorite virus scanning program (such as Disinfectant INIT, SAM, Virex, Rival, etc.) in each folder. 4. Each of these full system folders should be clearly labelled with its distinguishing characteristics (e.g., "System 6.0.7", "System 6.0.4", "KanjiTalk System"). These system folders should all then be placed into a single folder, which should be labelled "System Folder" and kept in the lower-left corner. 5. Use the shareware product Blesser (or equivalent) to switch between systems. Be deliberate about which system you use, and always reboot after changing systems. 6. Remember that you can always determine which system version is in use by choosing "About the Finder..." from the Apple Menu when running the Finder, or by observing which of the sub-folders within the System Folder contains the Macintosh picture on its Icon. 7. If you don't know what the Finder is, you shouldn't proceed beyond step 2 above. :-) Happy computing, Michael Odawa Simple Software odawa@well.sf.ca.us