Hi Paul!
> I used to think that older BIOS cannot boot GPT partition, but I now > believe the work to handle GPT is done by the MasterBootRecord. And so, > it seems to me that there is not much reason to create MBR partition tables > today. No. You either have a BIOS (which boots MBR) or UEFI (which boots GPT) or both (UEFI with CSM which simulates BIOS to boot legacy OS). If you have a GPT partition table, you also often have a placeholder MBR to keep people from making new partitions in case they overlooked the GPT partitions while using old partitioning tools. So you can boot from a lot of places, but if you talk about DOS, it will simply not work on UEFI without CSM or BIOS even if you can boot it. There is work on making FreeDOS understand GPT partitions and Bret Johnson's USB drivers ALREADY do understand GPT. So when you plug in USB disks or sticks with FAT partitions and GPT partitioning, the drivers will assign a DOS drive letter for them :-) But you still cannot boot DOS itself without "legacy" support because without BIOS interrupts, many things in DOS break, both in apps and kernel. PDOS/386 aims to have the option of using UEFI calls instead of BIOS interrupts for the kernel, but this still means that only DOS apps without expectations about anything from the BIOS would work. Also, it will probably only run protected mode DOS apps which expect either DPMI or some DOS32A style protected mode int 21 in the near future. At the moment, it only runs apps specifically compiled for PDOS/386, I think? One could add a VM86 host engine and a sort of self-made CSM to PDOS/386 (or to FDPP, the DOSEMU2 protected mode fork of the classic FreeDOS kernel) to run classic DOS apps on UEFI- only systems, I guess. If FreeDOS would convert an existing MBR partition scheme into a GPT partition scheme, at the moment it would just break the ability of old OS including FreeDOS itself to access it, unless it is an USB disk NOT booted from :-p Cheers, Eric PS: I hope I remembered the things about PDOS/386 correctly! _______________________________________________ Freedos-devel mailing list Freedos-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-devel
