[syslinux] isohybrid: slint64-14.1.iso: unable to find mac efi image

[Thomas Schmitt]

Hi,

> I don't understand why you say "*But* the El Torito...". I don't see 
> a difference with what the mkisofs manual says.

The manual announces "Mac" for Apple Mac.
The program obviously writes Platform Id 1 in this case.
The El Torito specs say "Platform ID 0 = 80x86 1=Power PC 2=Mac".
In the sum this does not match.
A bug in mkisofs would be the simplest explanation.


> My understanding is that: 0=x86 , 1=PowerPC , 2=Mac 
> are all non-EFI systems

Yes. EFI is younger than this specification.
The Platform Id 0xef was obviously introduced later.


> So, users should be more specific (or clear) when they refer to a 
> "Mac" system, as the firmware could be non-EFI, or (some variant of) 
> (U)EFI.

The El Torito Platform Id 2 refers to non-EFI Macs.
Possibly with MC68000 processors although at that time,
Macs were mostly equipped with Power PC.

The "--mac" of isohybrid probably refers to Intel Macs.

But all these fine details only matter at boot time.
Didier's problem is at isohybrid time.
And there it is fully explainable by the source code of
isohybrid.c. This code was obviously added to support mjg59's
Fedora ISOs.

Of course one could easily modify isohybrid.c to tolerate
platform ids other than 0xef.
This would make sense if indeed some computer boots from CD
only via platform id 1 (or 2). It could be tested without
isohybrid.
For the GPT and APM aspects, the El Torito platform id is of
no significance.


Nevertheless i advise Didier to simply try with 0xef rather
than Mac. At least the ISO will then have MBR, GPT and APM
entries for the file macboot.img.


Have a nice day :)

Thomas