gks@doc.ic.ac.uk (Gary K Smith) (03/05/91)
I am writing a Hard Disk Archiver - which Multi Tasks in RISC OS. Does anyone know the RISC OS way of signifying a change of disk? At the moment, I am using *Mount and *Dismount - but this needs some work to decode the File String Passed to it, and call ADFS:MOUNT or SCSI:MOUNT, and the Dirve number. Also, The PRM says that these two commands are provided for compatibility only, so there must be another way to change the disk. Thanks for any Help Gary. --
kvj@rhi.hi.is (Kristjan Valur Jonsson) (03/11/91)
In <2984@gould.doc.ic.ac.uk> gks@doc.ic.ac.uk (Gary K Smith) writes: >I am writing a Hard Disk Archiver - which Multi Tasks in RISC OS. In all this talk about Hard Disk Archivers, I have noticed that people want to have them multi tasking. Why is this? I can come up with several reasons why a HDA should NOT be multi-tasking: 1) File tree corruption: If one changes the file tree during archiving, the resulting archive can get upset. The archiver must take great care not to mix things up. In general, I consider it best to take a copy of it all in one go, and not allow other programs to interfere during the process. This should mean maximum reliability. 2) Speed is a very important factor. People tend to avoid backing up their HDs because of the complete boredom of it all. There is a lot of time overhead in coping with a multi tasking wimp, and most compaction routines hate to get interrupted (or rather interrupt themselves). 3) A smaller program will allow a larger memory buffer, thus speeding up the archiving. It could even change to mode 3 for maximum memory/speed. 4) etc. Multi tasking wimp programs are nice, but no one will ever bother archiving his HD while doing other work simply because of the constant disk swapping involved. Unless, that is, one posesses a tape streamer or a similar device. Summary: there are the natural multi tasking programs, and there are the natural single tasking ones. Regards, Kristjan