Greywolf <greywolf@starwolf.com> writes:

> # > - They all send the same signal, but with a magic identifier somewhere
> # >    in the stuff that gets passed to the signal handler.
> # 
> # You mean, the signal "code" parameter, where we already pass auxiliary
> # signal information (albeit only for traps)?
> 
> After reading up on kill and company, I cannot see how an external process
> can send anything else down that pipe!  That would really make it
> difficult for that one to work.

It's true that other processes don't get to do that, but we're talking
about messages communicated from the kernel. The kernel uses
trapsignal() all the time to pass extra information about various
things in the sigcode.

        - Nathan