4.2 signal handling

[Paul Philp]

I have just discovered that 4.2 BSD signals do not
interupt system calls. Is this absolutely true,
or is it an option, or does it depend on something else.
This will make porting a whole ton of existing software
incredibly difficult.

On the other hand, it will make error processing considrably
easier. Either way, it would be nice to know what I am
getting into with 4.2, and I can start taking proper
precautions with any software I write in the future.

				Paul