I think the best way to do this is to have ktrace request a newer version 
   of the file format. That's the only way you can know what version of the 
   file format userland can deal with. So it sounds like it's time to version 
   the ktrace syscall. :-|
   
   Oh, I am assuming that kdump will be in sync with ktrace. Since userland 
   gets updated all-at-once, that assumption seems fine. This way ktrace will 
   never ask for a file format its kdump can't understand.


it was my understanding that ktrace doesn't actually write the records
to disk, but the kernel does directly.  one would assume that ktrace/kdump
would be in sync, yet, but i didn't think that helped...


.mrg.