> The old PT_READ_U and PT_WRITE_U certainly didn't do this, and there's
   > no code in GDB to support it that I'm aware of.  Furthermore, this
   > information is *not* kept in struct user; it's kept in another
   > per-process structure that hangs off struct proc.

   Oops.  Should have read it a bit more carefully, that way I, too, would see
   that proc has a p_sigacts pointing into user's u_sigacts...

Actually, you're right.  B-)

I still don't know of any code in GDB to support that, though, and we
could just as easily provide another ptrace(2) function to get that
info.

Another thing (suggested by Roland) that would be useful is to have a
set of signals which are passed directly to the child without telling
the debugger about it.  This would be particularly useful for programs
that use SIGIO (like Emacs).

Did I hear you volunteer?