DOS ain't dead

BD-R with UDF filesystem - FS redirector with 64-bit sizes (Miscellaneous)

posted by ecm  , Düsseldorf, Germany, 25.12.2020, 21:24

> > Khusraw's DOS port of MPLAYER can play (unencypted) Blu-ray discs, but
> only
> > if formatted in ISO9660 standard, as there's no UDF driver. The problem
> is
> > in MS-DOS, filesizes > 2GB aren't readable due to signed longint
> > limitation.
> >
> > There's an experimental exFAT reader for DOS as well, but the problem
> again
> > is that filesizes > 2GB aren't readable, so that completely defeats the
> > purpose of having an exFAT driver in the first place. The raw assembly
> code
> > of MSDOS.SYS and / or IO.SYS needs to be modified somehow. Even if
> > possible, I do not know if filesizes > 4GB can be directly supported.
> >
> > Same issues for the R. Loew drivers (I think?), or did he somehow
> magically
> > erase and / or patch the 32-bit longint limitations on filesizes as well
> as
> > increase sector sizes and capacities of drives beyond the 2TB limit? I'm
> > not sure, as I've not personally tested those drivers.
>
> It is possible for a file system redirector (like for ISO 9660, UDF, exFAT,
> NTFS, or dosemu's host FS) to support 64-bit file sizes and seeks in a
> manner compatible to the FAT+ support of Enhanced DR-DOS. That means
> expanding the SFTs with extension fields (can be stored in file handle
> tables of the redirector), hooking the new-style interrupt 21h service
> 7142h for large seeking, and service 42h to make old-style seeking somewhat
> aware of the large size support. I did this
> for dosemu2's mfs.
> Technologically it works, but it was rejected on other grounds.

A subsequent revision of my patch got merged today.

---
l

Complete thread:

• BD-R with UDF filesystem - david, 17.12.2020, 10:26 (Miscellaneous)
  • BD-R with UDF filesystem - RayeR, 18.12.2020, 15:14
    • BD-R with UDF filesystem - bretjohn, 19.12.2020, 21:57
      • BD-R with UDF filesystem - Zyzzle, 20.12.2020, 10:06
        • BD-R with UDF filesystem - bretjohn, 21.12.2020, 21:33
          • BD-R with UDF filesystem - RayeR, 21.12.2020, 23:01
            • BD-R with UDF filesystem - RayeR, 25.12.2020, 09:19
              • BD-R with UDF filesystem - RayeR, 26.12.2020, 22:53
                • BD-R with UDF filesystem - Zyzzle, 27.12.2020, 04:02
                  • BD-R with UDF filesystem - RayeR, 27.12.2020, 21:10
          • BD-R with UDF filesystem - Zyzzle, 22.12.2020, 04:44
            • BD-R with UDF filesystem - RayeR, 22.12.2020, 05:46
              • BD-R with UDF filesystem - Zyzzle, 22.12.2020, 06:14
            • BD-R with UDF filesystem - FS redirector with 64-bit sizes - ecm, 22.12.2020, 12:50
              • BD-R with UDF filesystem - FS redirector with 64-bit sizes - bretjohn, 22.12.2020, 19:03
                • BD-R with UDF filesystem - FS redirector with 64-bit sizes - tom, 22.12.2020, 22:05
                  • BD-R with UDF filesystem - FS redirector with 64-bit sizes - RayeR, 22.12.2020, 23:43
                    • BD-R with UDF filesystem - FS redirector with 64-bit sizes - bretjohn, 23.12.2020, 19:51
                      • BD-R with UDF filesystem - FS redirector with 64-bit sizes - RayeR, 23.12.2020, 21:15
                        • BD-R with UDF filesystem - FS redirector with 64-bit sizes - Zyzzle, 24.12.2020, 04:18
                        • BD-R with UDF filesystem - FS redirector with 64-bit sizes - rr, 24.12.2020, 13:41
                • BD-R with UDF filesystem - FS redirector with 64-bit sizes - mceric, 23.12.2020, 02:31
                  • BD-R with UDF filesystem - FS redirector with 64-bit sizes - RayeR, 23.12.2020, 19:37
                  • BD-R with UDF filesystem - FS redirector with 64-bit sizes - bretjohn, 23.12.2020, 22:24
                  • BD-R with UDF filesystem - FS redirector with 64-bit sizes - bretjohn, 27.12.2020, 16:40
              • BD-R with UDF filesystem - FS redirector with 64-bit sizes - ecm, 25.12.2020, 21:24