Jython process doesn't terminate

[trofimander]

Steps to reproduce:

• Run some trivial script under debug with Jython 2.5.4rc1 like

x = 1 
print (x)

Result:

• The process hangs forever until terminated manually

[fabioz]

Note: this happens because of a Jython bug:

def func():
import threading
print threading.currentThread().isDaemon() # That version of Jython says its not daemon when it should be!

thread.start_new_thread(func, ())

Still checking a workaround...

[fabioz]

Fixed in bbf5251

[trofimander]

True. I've just checked it.
The thing I don't understand why is it daemon in CPython? Documentation says that main thread is not daemon, as well as all other threads started from main thread are not by default.
So it is rather bug in CPython old API then in Jython.

[fabioz]

Well, the docs say mostly about threading.Thread, but the thread.start_new_thread doesn't create an entry in the threads, so, if you call threading.currentThread() in that case it returns a dummy thread...

Which has in its implementation the following note:

Dummy thread class to represent threads not started here.
These aren't garbage collected when they die, nor can they be waited for.
If they invoke anything in threading.py that calls current_thread(), they
leave an entry in the _active dict forever after.
Their purpose is to return something from current_thread().
They are marked as daemon threads so we won't wait for them
when we exit (conform previous semantics).

[trofimander]

Thanks for the clarification!