Re: Max Size

[shack@pro-ict.cts.com (Randy Shackelford)]

david@wraith.cs.uow.edu.au (David E A Wilson) writes:

>shack@pro-ict.cts.com (Randy Shackelford) writes:
>>If you mean ProDOS 8 the number of
>>volumes accessible at the same time is eight. That includes RAM disks and
>>volumes on floppy drives as well. Wouldn't be very useful to have more volumes
>>than the operating system can handle.
>
>Depends on your usage. The first limitation is the 14 volumes that the 4 bits
>of unit number give you (slot 0 drives 1 & 2 are not used [although I once
>used drive 2 for /RAM just to see if it worked and it did]).
>
>The second limitation is that you can only have 8 files open at the same time
>and if these are on different disks then 6 of your volumes will be idle. This
>is not a problem. How often do you use more than 2 volumes at once (copying
>files usually)? The fact that they are sitting there on-line means that you do
>not have to remove one disk and insert another.

NOOO!! There is an absolute limit of eight volumes at a time. That is because
the Volume Control Block, the table which keeps track of what volumes are on
line and the devices on which they reside, has room for only eight entries.
This is similar to the File Control Block, which holds info on open files and
also only has room for eight entries.

I tried it out once by hooking all my hard disks and floppies up to one
machine and putting disks in all the drives. Once you get eight volumes you
can't see any more.
--
Randy Shackelford                              "That's right, keep dancing
shack@pro-ict.cts.com                           on the minefield"
                                                                 -Al Bundy