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Troy Martin wrote:Similar question: has anyone written their own partition table system and tools to use the partitions and the filesystems on them?

Even the MBR has more than one flavour. The original MBR description (you can find the info somewhere on the IBM website in a .boo document) was quite different from Microsoft's implementation (which is now the accepted standard). I thought about implementing my own but I want people to be able to use my OS on their machines in a compatible manner.

Troy Martin wrote:Similar question: has anyone written their own partition table system and tools to use the partitions and the filesystems on them?

I don't think modifying the partitioning system for your own use is going to help with integration, as it means no other OS can make use of the disk anymore.

First, I think everyone here has an FS or wants an FS in his OS. An OS without a FS is not very usable, in my opinion.

My OS primary uses iso9660 and ramdisk, but I have also a driver for ext2 and I'm writing a driver for FAT* (reading works already). I also ported FUSE to my OS, so it should be easy to "port" any FS to my OS, but for the moment my libc is just too small.

Well, I'm currently writing a new MBR that enables LBA-48 while maintaining backward compatibility with existing partitions (I hope). I fixed a few issues like the misaligned data objects, and leave room for 64 bit LBA entires. So far I have written the support for CHS only systems, and standard LBA-32 as I call it. I have 202 bytes of user codespace left to do it in The caveat of course is that drives over 2TB are a bit expensive atm, so I guess Ill have to wait to test it, and it assumes that INT 0x13h subfunction 0x42h in your BIOS actually uses the additional bits.

abachler wrote:while maintaining backward compatibility with existing partitions (I hope).

I fixed a few issues like the misaligned data objects

What are you talking about?

If you want, you can get Simplexity's (my OS) MBR from its repo (see signature). It handles both CHS and LBA, checks for overlapping partitions and sees if the MBR gives invalid parameters (needs to access data beyond the size of the disk; for CHS it checks the individual fields to see if they are <= than the disk's). It also features the 3 standard error messages that a MS MBR would give and, unlike other MBRs I've seen, it doesn't halt on ECC, for god's sake Enjoy!

Wheres the fun in that?

Where's the fun in using GRUB? That doesn't stop people who want to concentrate on different things, other than bootstrapping. I only offered my MBR to whoever wants to use it. If you want to code your own, be my guest. Anyway, we're getting OT here (I'm trying to be more careful about these things ).

I have maded my own FS, but it might need some rewriting (optimizing...)
but as the others says: IT is a MUST, if you want to do anything usefull with an OS.

KMT dk