On Sun, 28 May 2006, Arkady V.Belousov wrote:
28-Май-2006 15:10 [EMAIL PROTECTED] (Bernd Blaauw) wrote:
4DOS supports the same, but there's not much known about what 4dos
specifically supports:
*fat32?
Command shell can't and shouldn't support FAT32, command shell should
use OS services (API) to access file system. And yes, 4DOS shows sizes more
than 4G.
I think Bernd meant exactly that - does it show file sizes
above 2 GB and "total size" and "free size" above 4 GB in DIR?
I would like to add: Can it write files of 4 GB size or is it,
like the FreeDOS kernel, limited to 2 GB in some aspects?
Note that FAT32 does not support files larger than 4 GB. It does
support longer fat chains, and some software used that to access
larger files, but the directory entry is "officially" limited to
describing files of max 4 GB size.
*vfat?
"vfat" is a Windows name for drivers, which implements LFN and doesn't
relates to 4DOS.
If you ask me, then VFAT also describes extensions like "last access time"
and "creation time" in directory entries. As somebody said earlier,
last access time is a bad idea (has to be updated very often, bad for
performance), but "creation time" would be easy to implement: It can
be set as soon as the timestamp of an existing file which has no
creation time yet is changed: Then, copy the "classic" timestamp to
the creation timestamp field. If creation timestamp is already set,
do not update it anymore. There are also int 21.57xx extensions to
explicitly get or set the other timestamps, should also be easy to
implement...
In addition, VFAT describes the idea that Win9x keeps the whole FAT
in RAM for efficient processing of in particular FAT32 (Win9x has
a limit of 15.x MB FAT size, by the way) and probably some other
properties of the Win9x FAT drivers... So I would assume that
Arkady is right but that Bernd meant the extra timestamps and not
the drivers...?
*long file names?
Yes.
Nice. FreeCOM only supports them for a few commands (DIR and
CHDIR?) and only in 0.84pre... BY THE WAY, did the bug about
LFN get fixed? I remember that 0.84 tried to use LFN for ALL
drives as soon as at least ONE drive supported LFN, which did
of course not work out...
4DOS's disadvantage is that it's HUGE, both in memory usage and disk size.
Yes. :(
I think it is also not very FreeCOM compatible yet ;-)
So: It is a cool shell for everyday use but there are
several batch files which are FreeCOM specific in the
distro. I noticed that beta9sr2 even contains (in a zip
in a diskette image in the iso, yuck!) a file which uses
SET /U LANG=%LANG% which must be an undocumented feature
which exists only in 0.84, not in 0.82pl3... I would
recomment NOT to use features beyond 0.82pl3 in batch
files in the distro unless you really have to.
As you will usually have XMS around, both 4DOS and FreeCOM
have almost the same low memory footprint, but I agree that
4DOS is not at all suited for diskette distros. It is,
however, nice for "plain bootdisks", in the same way that
the busybox and sash Linux shells are nice for plain boot
disks: If not much apart from the shell will be on the
disk, you can just as well use a big and versatile shell.
Eric
