Re: DOS 3.3 on hard disk?

[rubywand@swbell.net]

Matt Ackeret (mattack@area.com) writes ...

<<
In article <5e6f0k$2sm@news.istar.ca>,
Nick Belner <bogus.id@istar.NO-JUNK-MAIL.ca> wrote:
>For various obscure reasons I would like to get DOS 3.3 going
>on a small (20 meg) SCSI hard drive. ....

Another solution is DOS 3.3 Master from Glen Bredon, the same guy who
wrote ProSEL. ....

DOS 3.3 Master makes a big ProDOS file that "contains" the DOS 3.3 volume,
then you run a special program to switch into DOS 3.3 mode.  Then you
have a whole bunch of 400K volumes, just like on the real hard drives that
natively support(ed) DOS 3.3...   There is a special utility (that works
like FID, I think???) that lets you copy back and forth from ProDOS to the
DOS 3.3 area. ....
>>


     There have been a few mod versions of DOS 3.3 which allow using disks much larger 
than the standard 140k 5.25" diskette. One was released by Nibble several years 
ago. Possibly, a DOS 3.3 that can handle a 20MB hard disk exists.

     In any case, we may have to accept certain realities about DOS 3.3. It was not 
designed to handle large format disks. Each time someone starts to modify DOS 3.3 for 
hard disk, the changes seem to move towards ... ProDOS! Basically, ProDOS _is_ "DOS 3.3 
for hard disk".

     About the closest one can get to DOS 3.3 on a typical IIgs hard disk is

 1. employ a ProDOS utility which requires conversion of DOS 3.3 files and simulates a 
DOS 3.3 environment; or,

 2. employ a program switcher which will allow interrupting, storing, and re-starting a 
DOS 3.3 program.


     The best way to run DOS 3.3 wares from hard disk is to change them into 
standard ProDOS wares. This may require a session with Program Writer to modify some 
commands and file names along with a Copy II+ session to change file names to fit 
ProDOS.

     Some DOS 3.3 programs can be copied to a ProDOS diskette and run with no changes at 
all. Some, such as those which use memory protected by ProDOS (e.g. do a direct BLOAD 
into the Text Page), will be trickier to convert. A few copiable programs which 
incorporate anti-mod protections may be very difficult to modify for ProDOS.


     It is easy enough to talk about a "fully operational DOS 3.3 FST for System 6". It 
will, however, never happen. DOS 3.3 is doable; but, its capacity for modification is 
not. Too many DOS 3.3 programs make on-the-fly patches to DOS and/or do direct calls to 
'non-standard' entry points. There is no useful way to implement DOS 3.3 on hard disk 
without incurring a high risk of having everything trashed the first time some oldie 
diddles the system code.