Theory of Operation

[probonopd]

It would be very helpful to have some "Theory of Operation"/flowchart. E.g., something like this (example - the content is just a wild guess):

Ventoy Theory of Operation

• The Ventoy bootloader (grub module <insert name here>) exports Ventoy data as hints for the kernel (variables hint.ventoy.0.disksize, hint.ventoy.0.diskuuid, hint.ventoy.0.disksignature, hint.ventoy.0.segnum)
• The bootloader checks whether it should inject the Ventoy kernel module into the ISO. The kernel module should only be injected into the ISO if the ISO doesn't come with the kernel module preinstalled
  • If the ISO is marked "Ventoy Compatible", then...
  • If the ISO is not marked "Ventoy Compatible" but also does not ship the Ventoy kernel module (e.g., the official FreeBSD ISOs), then...
• The kernel module reads the hint.* variables and compares them to every disk. If there is a match, it prints ######## ventoy disk <...> ########
• The kernel module then...
• COPYRIGHT...
• ...

[probonopd]

I need to load the Ventoy kernel module only if helloSystem is booted by Ventoy. For this, I need to check using the FreeBSD bootloader whether hint.ventoy.0.diskuuid (or any of the other hints) or VENTOY_UNIX_SEG_MAGIC0,... is set. Only then the FreeBSD bootloader should load the Ventoy kernel module. But the FreeBSD bootloader doesn't seem to know about these hints, they are not shown in list at the FreeBSD bootloader prompt.

How can the FreeBSD bootloader prompt know whether they are set? @ventoy