ccastbs@prism.gatech.EDU (Shannon Bell) (07/27/90)
I was mulling over FST pros and cons, and it occurred to me: the major problem with an FST is that it has to be worked into the entire system because it probably needs a slightly different interface than any other FST. (I'm sure someone will correct me if I'm wrong. At least, I hope so.) Would it be possible to crate an FST with exactly the same interface as one already available (Prodos, I guess) but with some of the limitations removed? GS/OS would make the same calls as it would to Prodos, and get the same info back, but the actual device could hold >32 Meg, possibly handle more than two volumes on a slot (though I have a hunch this would be considerably tougher), etc. Is this a feasable idea? Shannon Bell ccastbs@prism.gatech.edu
dlyons@Apple.COM (David A. Lyons) (07/28/90)
In article <11886@hydra.gatech.EDU> ccastbs@prism.gatech.EDU (Shannon Bell) writes: >I was mulling over FST pros and cons, and it occurred to me: the major >problem with an FST is that it has to be worked into the entire system >because it probably needs a slightly different interface than any other FST. I believe the problem is more that the interface between FSTs and the OS is not *stable* to anywhere near the degree the Device Driver interface is. Currently, whenever a new GS/OS call is added, or whenever an existing call is modified to allow more parameters, all FSTs have to be modified correspondingly. >Would it be possible to crate an FST with exactly the same interface as one >already available (Prodos, I guess) but with some of the limitations removed? They *do* all have the same interface (except for extra FSTSpecific subcalls, of course). Besides the ProDOS FST, there are *currently* (in System Software 5.0.2): --AppleShare FST, for accessing file server volumes on an AppleTalk network (allows up to 14 server volumes, and the volumes can be huge) --ISO 9660 / High Sierra FST, primarily for accessing CD-ROM disks, but it also works for floppies if you happen to have an ISO/HS floppy lying around. This is a read-only FST. --Character FST, for accessing character devices (console driver, serial ports, etc). >GS/OS would make the same calls as it would to Prodos, and get the same info >back, but the actual device could hold >32 Meg, possibly handle more than >two volumes on a slot (though I have a hunch this would be considerably >tougher), etc. Is this a feasable idea? Having more than 2 devices per slot is NO PROBLEM for GS/OS! I have a 80-meg hard drive sitting here on my desk, attached to my GS SCSI card. 3 partitions on the HD, several more if I stick in a CD-ROM disk into the CD-ROM drive, and they all show up. >Shannon Bell ccastbs@prism.gatech.edu -- David A. Lyons, Apple Computer, Inc. | DAL Systems Apple II Developer Technical Support | P.O. Box 875 America Online: Dave Lyons | Cupertino, CA 95015-0875 GEnie: D.LYONS2 or DAVE.LYONS CompuServe: 72177,3233 Internet/BITNET: dlyons@apple.com UUCP: ...!ames!apple!dlyons My opinions are my own, not Apple's.