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Well I decided to make a dos bootdisk from windows xp. And I noticed when I tried it out my cd rom drive, and fat32 and ntfs partition where not accessable.

I had a look in autoexec.bat and config.sys and noticed both where completely blank.

Anyway, it's been years since I played with those 2 files in dos... and I don't remember how to mount(correct term for this?) my drives for access. So what do I need to change in autoexec.bat and config.sys to be able to access them?

I need my first primary partition(NTFS) mounted as c:, my cd-rom drive mounted as d:, and my extended partition which is the 6th partition(FAT32) mounted as e:.

Then I have my second primary partition which is ext3, but I doubt I can mount that since I don't think dos will be able to read a ext3 file system?

I don't know if it will be of any help, but this is what my parition table looks like: hda1 is windows
hda2 is ubuntu
hda6 is a fat32 partition for shareing files between linux and windows
hda7 is mounted as /home in linux.

DOS can only read FAT filesystems, mounting isn't possible at all. DOS autodetects drives at startup using the BIOS but if the partition isn't within the first 8GB of the HDD then it won't "find" it. These are all technical limitations, it may be possible to hack your way around them but you'd need to write a bunch of drivers...

For the CD Drive there is a program called MSCDEX or something like that which is used for running CD Drives but I'm not sure where you'll get it from (Win98 has it I think, don't know if it needs HIMEM, it probably will...)

Ok... well option 2. I need a tiny os that's command line and can fit on a floppy... preferably linux, and I need it to be able to write to FAT, and EXT3. And NTFS support would be optional but would be nice, although I doubt I will find one since it's still unstable to write to NTFS from linux.

Chances are floppy is out of the question... I do see one linux os called "damn small linux", but it's 50MB. 49MB too big.

But if I decide to use a usb flash drive looks like that would work.

Regarding CD-ROM drives: Correct, you need MSCDEX to access a CD-ROM under a drive letter. But for MSCDEX to "mount" your CD-ROM, you must have loaded a driver first. You don't need himem.sys for that, but it allows you to load the driver with DEVICEHIGH= instead of DEVICE=, leaving more base memory for whatever app you want to run.

The Win98SE installation CD boots using an emulated floppy; that floppy image contains a driver oakcdrom.sys, which did work for me with all IDE controllers I owned.

Just for what it's worth. AFAIK, there's no way you'll be able to access NTFS and ext3fs from the same boot floppy, so I guess USB stick is the way to go if you can't use some LiveCD (Knoppix).

AR wrote: DOS can only read FAT filesystems, mounting isn't possible at all. DOS autodetects drives at startup using the BIOS but if the partition isn't within the first 8GB of the HDD then it won't "find" it.

DOS can also only use 2GB partitions formatted with FAT16. If you use win95OSR2 or higher DOS-mode you can use FAT32, but you also gain partition type 0xC which allows the OS (and iirc also the DOS) to look beyond the 8GB limit.

You could have a look at Puppy Linux. I've not yet checked how up-to-date it is, but they claim that one can easily install it to a usb flash drive, as long as it is a bootable one (I can remember that there were hardware limitations too for booting of a usb flash disk).

cheers Joe