Clem Cole wrote:
> MIT had a modified a.out format for the NU machine ports - that might
> have been called b.out.  CMU had macho which again was an extended
> a.out but even more flexible.

Digital Research's GEMDOS also used a modified a.out format (at least as
found on the Atari ST), pretty much the original PDP-11 format with
32-bit addresses.