Baslinux mailing list

[3aoo-cvfd AT dea.spamcon.org]

James Miller wrote:
>
> I know about umsdos, which is a way to use a DOS filesystem on Linux.  

With UMSDOS, the Linux files are actually DOS files.
It runs on a DOS-type filesystem, with all the problems
that entails.

> But fs.img appears to be an ext2 filesystem.  

Yes, it is a standard ext2 filesystem (with e2fsck run at 
system startup).  

> Is it somehow ext2 on top of FAT or something?  

Think of fs.img as a ramdisk image (in fact, if you had a 
kernel that supported 15mb ramdisks, you could gzip fs.img 
and use it for initrd in boot.bat).  However, instead of
fs.img sitting on a 15mb block of RAM (in a ramdisk), it
is sitting on a 15mb block of file space.  

> I suppose it gets mounted as the loop "device" when BL3 
> is booted?  

Yes, the initrd ramdisk (87kb) mounts /dev/hda1 and looks
for /baslin/fs.img.  If it finds it, it does a loop mount
of fs.img and them boots that as the root filesystem.  You 
can actually see the initrd ramdisk in BL3.  

When you do df, you will see something like this:
---------------------------------------------------------
/dev/hda1          ?????       ?????     ?????    /DOS
/dev/loop0         15031        4666     10364    /
/dev/root.old         87          84         3    /initrd
---------------------------------------------------------
The first line is your DOS partition.  The second is BL3.
The third is the initrd ramdisk.  BTW, you can probably
delete the files in the ramdisk and use the space for 
something else (wow, a whole 87kb) but you won't be able 
to umount DOS from /initrd (because the only access to 
fs.img is via that mountpoint).

Cheers,
Steven