On Tue, 1 Aug 2000, Steffen Winterfeldt wrote:
> On Mon, 31 Jul 2000, Bart Oldeman wrote:
> > On Fri, 28 Jul 2000, Alistair MacDonald wrote:
> > > On Thu, 27 Jul 2000, Ralph Alvy wrote:
> > > > Will dosemu be able to access partitions beyond the 8gb barrier? Normal DOS
> > > > can't. I assume it will be able to, since it's relying on linux to do that
> > > > work for it.
> > >
> > > If you mean partitions that *start*/*finish* beyond the barrier then, if
> > > Linux/your system/etc. supports them, you should be able to. If you mean
> > > partitions whose *size* breaks the 8Gb barrier then probably not, because
> > > we still have to emulate the FAT.
> >
> > I've researched it a bit further, and the 8Gb barrier is because of the
> > BIOS. The BIOS (to be precisely interrupt 13h) has a limitation of
> > 1024 cylinders, 256 heads and 63 sectors/track. With 512 bytes/sector this
> > gives 1024*256*63*512=8,455,716,864 bytes.
> > See the Large Disk HOWTO for more details.
> >
> > The emulated int13 in DOSEmu is no exception to this rule, except that the
>
> The extended BIOS call that uses 64bit block numbers is implemented in
> DOSEMU, so there should be no problem accessing large partitions. At least
> not more than usual.
As long as the DOS you use inside DOSEmu supports it. Is there any? Maybe
the DOS included with Windows 98? Fortunately it is a bit of a non-issue,
since lredir'ed drives work fine for almost all purposes.
> My experience with large lredir'ed filesystems (some GB) is that it
> depends on the apps you're running. Some can't cope with filesystem
> sizes >2GB, some can't handle filesystems with >2GB *free* space, some
> just don't work at all.
Which implies that these apps (calculating free space as a signed
32-bit value) also have problems running on a large FAT32/NTFS/HPFS
filesystem under any OS.
So just to stay on the safe side it's best to limit filesystems on which
you run DOS apps to 2GB.
Bart
