AWCTTYPA@UIAMVS.BITNET ("David A. Lyons") (02/04/89)
>Date: Fri, 3 Feb 89 05:40:46 GMT >From: Andy McFadden > <agate!e260-3f.berkeley.edu!labc-3dc@UCBVAX.BERKELEY.EDU> >Subject: Re: GS/OS cache; device drivers; trashed disks >I have *both* the UniDisk 3.5 and AppleDisk 3.5 drivers installed. >Perhaps GS/OS can't tell the difference and is using the wrong one >(although I find that hard to believe) or maybe the Universal Drive >Controller doesn't resemble a UniDisk closely enough (probably). Aha! I somehow missed that you were using a UDC. I don't have any solid facts for you, except that you need to be careful until you figure out what's happening! Can you trash disks "at will"? Can you trash them in the Finder, even though it polls the drives every second or so [I suspect you can't]? I don't think either the APPLEDISK3.5 or UNIDISK3.5 driver is doing anything w/ your UDC drives, but the "generated driver" GS/OS creates for your drive ought to remove all that device's blocks from the cache if it ever notices that there is no disk inserted (like when the Finder polls it between the time you remove a disk & the time you insert another one). You might do some experiments to determine whether it matters if the new disk has the same volume name or not. If it does matter, then the File System Translators are helping determine when disks have been switched, since the device drivers don't know anything about volume names. If anybody can shed more light on this, please do! My own copy of GS/OS Ref, vol 2 hasn't arrived yet; that should help _some_. >labc-3dc@widow.berkeley.edu (Andy McFadden) >c60c-3aw@widow.berkeley.edu (expiring soon) --David A. Lyons bitnet: awcttypa@uiamvs DAL Systems CompuServe: 72177,3233 P.O. Box 287 GEnie mail: D.LYONS2 North Liberty, IA 52317 AppleLinkPE: Dave Lyons