Handling and propagating signals

[bah@longitude.com]

> I was muttering about that in the pub with people last night.
> Apparently relying on process groups to work properly is a no-no.

It did strike me as being not terribly portable.  Is that the issue, or
are there no platforms on which process groups work properly?

> The most reliable way would seem to be fork/exec and waitpid.

Too bad it's sort of a pain...