[syslinux] Fwd: Re: How to understand partition table on hybrid ISO image?

[Didier Spaier]

Wrongly sent at first to the OP only, sorry.

-------- Forwarded Message --------
Subject: Re: [syslinux] How to understand partition table on hybrid ISO
image?
Date: Tue, 23 Feb 2016 12:15:20 +0100
From: Didier Spaier <didier at slint.fr>
To: Martin T <m4rtntns at gmail.com>

On 23/02/2016 00:37, Martin T via Syslinux wrote:
> When I try to understand what an hybrid ISO is, then looks like it is
> a regular(according to El Torito standard) bootable ISO, which is
> post-processes with isohybrid(?).
> Isohybrid(https://gist.github.com/jsarenik/e184b4061263dbd7d3a3) seems
> to add simply MBR to ISO. Is there anything else which makes a regular
> bootable ISO to hybrid ISO? In addition, how should one understand
> partition table on hybrid ISO image?

Instead of using e.g. mkisofs then post-processing with isohybrid you could
use xorriso.

For intance:
xorriso --as mkiosfs \
isohybrid-mbr /usr/share/syslinux/isohdpfx.bin <remaining options>

In case of BIOS + EFI you could add options like:
eltorito-alt-boot -e isolinux/efiboot.img \
isohybrid-gpt-basdat -no-emul-boot

To check the content of the ISO image:
xorriso -hfsplus on -indev <your ISO image> \
-report_el_torito plain -report_system_area plain

That's what I learned from Thomas Schmitt. Maybe he will step in and
tell you more.

Didier