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What the El-Torito specification says you can do, and what BIOSes actually let you do... have never been exactly aligned.

Assume that unless it's no emulation mode and 1 sector long, it is going to explode horribly.

Disturbingly often you'll be right.

Owen wrote:What the El-Torito specification says you can do, and what BIOSes actually let you do... have never been exactly aligned.

Assume that unless it's no emulation mode and 1 sector long, it is going to explode horribly.

Disturbingly often you'll be right.

My loader is no emulation mode, but it is certainly more than one sector long. I would be fairly well pissed off if it didn't load on other computers.

Hi guys, all good points.

Can we branch into this question.

How do I get my bootloader, which will contain my my OS into the CD so it will load upon boot.
The bootloader could be as large as 32k.
Using Windows.

Or should I just keep them as separate files??

Alistair,

The better way is to use separate files/areas. I use following boot order for CD/DVD: stage 1 -> [stage 2 ->] kernel.

Casm wrote:

egos wrote:All right, it is not one but a few sectors.

The Windows kernel is smaller than that.

I think most are

Casm wrote:You can call it whatever you like, but it is not a boot sector. It is an ordinary file; albeit a hidden one...
That is not a boot sector. It is a complete program - larger than MS-DOS programs used to be. Since all files on a CD are contiguous, it doesn't even have that to make it different.

The same way you can argue that the bunch of sectors located somewhere in a data area (may be in FAT16 file system), but not covered by existing file is just a hidden file. You are totally wrong! This is NOT a file since it doesn't need to be presented in ISO file structure (although may be if you want). But if you are worried about the number of physical sectors in it, then call it boot record. It will be correct term.