[comp.sys.apple] ProDOS Mods...

neilhncc1701d@pro-cyon.UUCP (Neil Haldar) (05/14/89)

     Someone on here spoke about 'home mods' to ProDOS that allowed it to
access volumes greater than 32megs... who was that? (Sorry). And how is this
done?? And... well, you got my attention... tell me more!
     Thanks...
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dlyons@Apple.COM (David Lyons) (05/16/89)

In article <8905150839.AA04530@crash.cts.com> pnet01!pro-sat!pro-cyon!neilhncc1701d@nosc.mil writes:
>
>     Someone on here spoke about 'home mods' to ProDOS that allowed it to
>access volumes greater than 32megs... who was that? (Sorry). And how is this
>done?? And... well, you got my attention... tell me more!

It isn't possible to have volumes larger than 32 megs, or files larger than 16
megs, and still have the volume be a ProDOS volume.  These limitations are
inherent in the volume format itself, not just in the implementation of ProDOS.

The important things are:  2 bytes are used for block numbers (65536 blocks =
32 megs), and 3 bytes are used for file positions (3 bytes = 16 megs).


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