How can we identify an ISO file is an EFI bootable ISO image?

[Heyi Guo <heyi.guo@linaro.org>]

Dear experts,

Is there any simple tool to parse ISO images (El Torito partition) and 
identify whether it is EFI bootable?

I think EFI bootable image should contain a FAT volume so that EFI can 
load bootxx.efi file from the file system.

Several tools like mount in Linux will show all files together including 
EFI/BOOT directory, so if an ISO image contains such files but not 
organizes the data in a FAT sub-volume as EFI requires, I can't see any 
difference.

So the tool would need to print the detailed internal structure 
information of El Torito ISO files. Is there something like that?

And is there any guide to create an EFI bootable El Torito ISO image?

Thanks and regards,

Gary (Heyi Guo)