[syslinux] Possible memdisk issue

[Alexander Perlis]

On 07/09/2014 04:00 PM, H. Peter Anvin wrote:
>
> So this would seem consistent that this is the FAT12/FAT16 boundary that
> breaks stuff.  Perhaps FreeDOS has a problem with FAT16 on floppies?

If I understand things correctly, a bootable floppy has two key pieces 
of executable code: the 512-byte boot sector, and the kernel loaded by 
that boot sector.

The kernel can be large, and thus could perhaps in principle auto-detect 
FAT12, FAT16, FAT32, whereas the boot sector code is limited to around 
460 bytes (as file system config data is also stored in there), so 
perhaps that's not enough space for auto-detection code? Perhaps there 
simply have to be 3 different boot sectors, depending on whether you've 
got FAT12, FAT16, or FAT32? That would explain what's happening here: 
newmkfloppyimg called mkdosfs, who made a different file system, yet 
newmkfloppyimg copied over the old file system's boot sector...

Does anyone know whether it is possible to have a "universal" boot 
sector and "universal" kernel? Then if one starts with a base floppy 
image containing those, then newmkfloppyimg should create something 
bootable no matter what size is specified.

Alex