[syslinux] Is it possible to chainload isolinux.bin file from syslinux

[Ady]

> I have a USB disk with syslinux files installed in /boot/syslinux, and the
> bootloader is installed into MBR or VBR
> 
> I then extracted a *.iso file which uses syslinux as the bootloader, into
> root dir of the disk. The iso file contains a rescue OS or an OS installer.
> Now I got the directory /isolinux with files isolinux.bin and isolinux.cfg
> in this folder
> 
> I can now boot into syslinux, but *what to do to boot/chainload the
> isolinux.bin file to launch the OS*?
> 
> Note that just load the isolinux config file /isolinux/ioslinux.cfg (using
> "config" module) instead of chainloading entire isolinux is not what I
> want. Because the version of my syslinux (official compiled binary) and the
> isolinux (from another verdor) may be different and the isolinux may
> contain some 3rd party patches. So just load the config file will sometimes
> result in failure.
> 
> My final purpose is to make a universal USB boot disk: It can boot any
> extracted iso as long as the iso file is made using isolinux.
> 
> So perhaps the most elegant solution to this is chainload isolinux from
> syslinux.
> 
 
When you say "_may_ contain some 3rd party patches", do you actually 
know there are 3rd party patches there?

You need to match the version of the c32 modules with the version of 
the bootloader. If the particular ISO image includes a Syslinux 
installer and all the relevant c32 modules for the same version, you 
could use those for your USB drive.

Unless there are specific reasons (such as a special c32 module that 
is not publicly available, for instance), using upstream official 
binaries would be (generally speaking) recommended for merging the 
content of multiple ISO images into one "multiboot" USB drive.

There are other options, such as loading the ISO image with MEMDISK 
or using a different bootloader. Each alternative has its own pros 
and cons.

Regards,
Ady.