Guido van Rossum writes:

...

Well, I'm not mixing threads and signals, really. I've now learnt that when a signal is directed at a process on BSD it is delivered to "a" signal from the set of signals that hasn't blocked it. ^^^^^^ ^^^^^^^

You mean theads, right?

thReads, yes :)

...

What I need to know, and can't quite work out, is how many threads are present when you just execute

$ ./python

and are sitting at the interpreter prompt? Is it just the one (the main thread)? That's what I thought, but I'm unable to explain the behaviour I'm seeing if that is indeed the case.

Python doesn't create any threads. On Linux, I know that when you start your first thread, the thread library creates an extra thread for some internal reasons. Who knows what BSD does though.

I'm not sure either, but I have convinced myself that signal mask handling is just buggered on BSD when the program is compiled in a multi-threaded style (as, in simple C programs don't do what you (well, I) would expect). Note this isn't about actually using threads -- just using "cc -pthreads". Now what do I do? Back my patch out? Not expose the functions on BSD? It works on Linux... Cheers, M. -- ARTHUR: Why should he want to know where his towel is? FORD: Everybody should know where his towel is. ARTHUR: I think your head's come undone. -- The Hitch-Hikers Guide to the Galaxy, Episode 7