Re: Mac Recognizing a ProDos volume

[stever@gate.net (Steve Reeves)]

In article <618bqc$93l$1@europa.frii.com>,
Randy Shackelford <shack@frii.com> wrote:
>[Article reformatted to be followup-friendly. Man I wish people would put 
>new text below quoted text]
>
>In article <34350509.1B8A@s2.sonnet.com>,
>Daryl Morgan  <dcm@s2.sonnet.com> wrote:
>
>>>Never heard that one, but I do know that PC Exchange will not recognize
>>>ProDOS partitions unless they are strictly less than 32 MB.  (I don't
>>>recall exactly how I partitioned my hard drive years ago, but I think
>>>it was with ADU, and it ended up with partitions that were exactly 32
>>>MB.  I had to shrink these by a block before I could get PC Exchange to
>>>mount them.)
>
>>How do you shrink the partitions without erasing the drive?
>
>There's a two byte value called total_blocks in the volume directory header,
>and it denotes how many blocks are on a volume. A little judicious block
>editing can reduce the number of blocks on the volume. You'd want to stay
>within the same multiple of 4096 blocks though, or else you'd change the
>number of bit map blocks necessary for the volume.

No, Randy, you're talking about the ProDOS volume itself.  I was
referring to the size of the partition in which the volume resides.  You
have to edit the device's partition map.

I don't know of any suitable tools for doing this on the IIgs (although
its possible if you have a good knowledge of the partition map's
structure with some judicious use of GS/OS Exerciser and NiftyList). 
On the Mac, there are several commercial programs that can do the job.
There is also a free utility called SEdit on Apple's developer site
that can do it.

-- 
Steve Reeves
stever@gate.net