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Re: The Virtual Partition - say goodbye to FAT12

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"Robert Wessel" wrote:
> "James Harris" wrote:
>> "Robert Wessel" wrote:

>>> I still don't get it.  Does the "standard OS" see this
>>> "virtual FAT32" volume or not?  Just part of it as a
>>> (subset) of a "real" FAT32 volume?

>>I am not sure I get it either but Mike can correct me.
>>AIUI he has worked out a way to format a FAT32 volume
>>which makes the volume as simple as FAT12 to access.
>>That includes things like putting the root directory a
>>the start. FAT32 allows it to go anywhere.

> That's my understanding as well.

>>In other words, it is a completely legitimate way to
>>lay out a FAT32 volume (so it is a normal FAT32 volume)
>>but it imposes some restrictions and thereby makes
>>processing the volume easier (i.e. in a lesser amount
>>of code).

> Fully agree.  Although IMO the mount of additional code
> needed to do this properly is very small.

>> > If so, how are you preventing the "standard OS" from
>> > doing something that messes up the subset your device
>> > needs to see?
>>
>>I think normal OS accesses don't modify any of Mike's key
>>changes.
>>
>>I'll be interested to hear if my understanding is right.
>>I think, in particular, there's some part of it that I
>>have missed.

> What's to prevent a defrag from moving the root
> directory?  What's to prevent the OS from extending the
> root directory, and then putting the directory entry for
> a file you're interested in after the 16th cluster of
> the root directory file?  What's to prevent the OS from
> putting a file (in the root directory) into a cluster
> past #2048 on the partition?  Or extending a file to a
> cluster>2048?  Or having defrag move it there?

_Absolutely nothing_ that the end user does not initiate.

> Now if the "standard OS" is not allowed to modify the
> volume (say this is intended to move data from some
> device to (say) a Windows workstation), the problems
> are reduced (there's not a good way to enforce such a
> read-only status).

Keep in mind that the Virtual Partition is designed to
be a simple system. Never the less and not withstanding,
the end user (or should I say - the beginner) is in full
control simply by following the protocol. See my previous
post to James.


Mike Gonta
look and see - many look but few see

http://mikegonta.com
http://tawk.to/mikegonta

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The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-03-31 17:51 -0400
  Re: The Virtual Partition - say goodbye to FAT12 Robert Wessel <robertwessel2@yahoo.com> - 2016-03-31 20:48 -0500
    Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-01 06:50 -0400
      Re: The Virtual Partition - say goodbye to FAT12 Robert Wessel <robertwessel2@yahoo.com> - 2016-04-01 11:06 -0500
        Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-01 13:45 -0400
          Re: The Virtual Partition - say goodbye to FAT12 Robert Wessel <robertwessel2@yahoo.com> - 2016-04-01 17:06 -0500
            Re: The Virtual Partition - say goodbye to FAT12 James Harris <james.harris.1@gmail.com> - 2016-04-01 23:16 +0100
              Re: The Virtual Partition - say goodbye to FAT12 Robert Wessel <robertwessel2@yahoo.com> - 2016-04-01 17:29 -0500
                Re: The Virtual Partition - say goodbye to FAT12 Rod Pemberton <NoHaveNotOne@bcczxcfre.cmm> - 2016-04-01 20:24 -0400
                Re: The Virtual Partition - say goodbye to FAT12 Robert Wessel <robertwessel2@yahoo.com> - 2016-04-02 00:10 -0500
                Re: The Virtual Partition - say goodbye to FAT12 Rod Pemberton <NoHaveNotOne@bcczxcfre.cmm> - 2016-04-02 12:03 -0400
                Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-02 20:19 -0400
                Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-02 20:08 -0400
                Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-02 20:02 -0400
                Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-02 19:55 -0400
              Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-02 19:30 -0400
            Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-02 18:55 -0400
              Re: The Virtual Partition - say goodbye to FAT12 Robert Wessel <robertwessel2@yahoo.com> - 2016-04-04 00:40 -0500
  Re: The Virtual Partition - say goodbye to FAT12 "wolfgang kern" <nowhere@never.at> - 2016-04-01 09:20 +0200
    Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-01 07:01 -0400
      Re: The Virtual Partition - say goodbye to FAT12 "wolfgang kern" <nowhere@never.at> - 2016-04-04 10:42 +0200
        Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-05 15:58 -0400
          Re: The Virtual Partition - say goodbye to FAT12 "wolfgang kern" <nowhere@never.at> - 2016-04-05 22:19 +0200
            Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-05 18:24 -0400
  Re: The Virtual Partition - say goodbye to FAT12 James Harris <james.harris.1@gmail.com> - 2016-04-01 09:55 +0100
    Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-01 07:11 -0400
  Re: The Virtual Partition - say goodbye to FAT12 Rod Pemberton <NoHaveNotOne@bcczxcfre.cmm> - 2016-04-01 20:24 -0400
    Re: The Virtual Partition - say goodbye to FAT12 "Mike Gonta" <mikegonta@gmail.com> - 2016-04-02 21:30 -0400

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