Actualy like Eric, privately, pointed out we already have a driver to treat a file as a volume, nl. SHSUFDRV.
However, the problem is not the driver, but what kind of file system should be used by such driver to make it compressed. We might just take SHSUFDRV and, like doublespace, assume that anything that is on it is compressed. Then add a compressor like LZO to compress/decompress everything going in and out. That way the file system does not even need to be changed. Imre >----- Oorspronkelijk bericht ----- >Van: Antony Gordon [mailto:[EMAIL PROTECTED] >Verzonden: vrijdag, maart 28, 2008 10:11 AM >Aan: [email protected] >Onderwerp: Re: [Freedos-devel] compressed FAT filesystems > >I've read all the posts, now lets look at what DriveSpace/DoubleSpace actually >did... > >You take a hard drive of x capacity, analyze the free space, a 'CVF' >(Compressed Volume File) with variable cluster size, move the files on the >disk into the newly created CVF file, compressing them in the process. once >the files have been moved into the CVF, it is mounted as a drive letter, and >if the file extension is .000, the drive letter is swapped with the host >drive. accessed through a block device that connects to a MRCI (Microsoft >Realtime Compression Interface) server. > >When I read about CVF and MRCI in the DOS 6 Programmer's Reference >(Microsoft), I thought that there had to be a much simpler way to implement >this. Especially after the lawsuit between DOS 6.0 and DriveSpace's appearance >in DOS 6.22. Of course, other things pressing I never really sat down to come >up with something, by that time Windows 95 was on the horizon, and you could >at least get up to an 800MB hard drive, and Disk Manager could help you use it >all. > >To effect the same principle in FreeDOS, a real-time compression interface >would have to be clean room designed based on the known aspects of >DBLSPACE/DRVSPACE integration with MS-DOS (or Stacker's integration with >MS/PC-DOS), perhaps in the process figure out how we can improve the design, >there is no need to be compatible, offer existing DBLSPACE/DRVSPACE users a >reliable migrate path and go from there. > > > > > >> Date: Fri, 21 Mar 2008 14:08:34 -0430 >> From: [EMAIL PROTECTED] >> To: [email protected] >> Subject: Re: [Freedos-devel] compressed FAT filesystems >> >> Would be OK something like a tar file, that includes time, date and >> attributes for each file. >> And may be compressed if needed. >> >> +-+-+-+-+-+-+-+ >> Marco A. Achury >> Tel: +58-(212)-6158777 >> Cel: +58-(414)-3142282 >> Fax: +58-(212)-2410828 >> Skype: marcoachury >> www.geocities.com/marcoachury >> >> >> >> Imre Leber escribió: >> > But then again, >> > >> > Do you realy need a file system if it is read only. You could just as well >> > use a table in the front that lists file names with path, and copy all >> > data after it. No need to have anything remotely like FAT and the like. >> > >> > Just: >> > >> > \temp\file1 start at 0 >> > \temp\file2 start at 1000 >> > >> > 0: data for \temp\file1 >> > 1000: data for \temp\file2 >> > >> > Not realy a file sytem, but should about the same. >> > >> > Imre >> > >> > >> > >> >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by: Microsoft >> Defy all challenges. Microsoft(R) Visual Studio 2008. >> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >> _______________________________________________ >> Freedos-devel mailing list >> [email protected] >> https://lists.sourceforge.net/lists/listinfo/freedos-devel > >_________________________________________________________________ >Watch “Cause Effect,” a show about real people making a real difference. >Learn more. >http://im.live.com/Messenger/IM/MTV/?source=text_watchcause ------------------------------------------------------------------------- Check out the new SourceForge.net Marketplace. It's the best place to buy or sell services for just about anything Open Source. http://ad.doubleclick.net/clk;164216239;13503038;w?http://sf.net/marketplace _______________________________________________ Freedos-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/freedos-devel
