FreeBSD: https://svnweb.freebsd.org/base?view=revision&revision=331949

Add the etdump utility for dumping El Torito boot catalog information.

This can be used to check existing images but will be used in the future to
find EFI ESP images placed in El Torito catalogs so they can be used for
hybrid boot purposes.

$ etdump /rpool/dc/media/OpenIndiana_Text_X86.iso 

Image in /rpool/dc/media/OpenIndiana_Text_X86.iso

Default entry

        System i386

        Start LBA 166 (0xa6), sector count 4 (0x4)

        Media type: no emulation
Section header: efi, final

        Section entry

                System i386

                Start LBA 167 (0xa7), sector count 8800 (0x2260)

                Media type: no emulation