Issue1313

It seems that 'except KeyboardInterrupt' or even plain 'except' is not
enough to catch ctrl-c with Jython. This is unfortunate because it makes
it prevents stopping applications started from the command line gracefully. 

This problem can be tested with the attached script. When I execute it
with Jython (tested both with 2.2 and 2.5b3) on my OS X and press ctrl-c
it simply quits without even a traceback. With CPython it prints both
'KeyboardInterrupt' and 'Bye!' before exiting cleanly.

Issue 1746106 is probably related to this problem:
http://bugs.jython.org/issue1746106

The same behaviour can be observed on Linux as well. If CTRL-C is
entered at the python command prompt, a KeyboardInterrupt is shown and
the command prompt appears again. This is handy when I am in the middle
of editing a line and just needs to get back to the prompt. How ever, if
the same is done in Jython, the interpreter exits. I tested with 2.5b3.
I am unable to add a new version to the tracker at the moment so I am
not selecting any version.

I'm currently using the following code as workaround:

import signal

def intHandler(signum, frame):
    print "user pressed ctrl-c"
    raise KeyboardInterrupt()

# Set the signal handler
signal.signal(signal.SIGINT, intHandler)

This installs a special handler for the interrupt signal, which raises a
KeyboardInterrupt.

I tested the workaround suggested by marc on 2.5.1 rc 3 but it didn't
work. After adding those lines to the attached ctrlc.py script, I wasn't
able to stop the execution at all. Pressing ctrl-c just gave the
following traceback every time I hit it and even 'kill -9' left a
defunct java process.

^CException in thread "SIGINT handler" Traceback (most recent call last):
  File "/home/peke/Prog/jython2.5.1rc3/Lib/signal.py", line 113, in handle
    self.action(signal.getNumber(), None)
  File "Lataukset/ctrlc.py", line 5, in intHandler
    raise KeyboardInterrupt()
KeyboardInterrupt


The reason I'm interested about this issue is that I'd like to implement
a possibility to stop Robot Framework test execution gracefully from the
command line: http://code.google.com/p/robotframework/issues/detail?id=108

It's not that straightforward to implement this like CPython does. Creating a signal handler that handles SIGINT is easy enough, but Java's signal support will call the handler in a brand new thread -- what you're really asking for is for Jython to always call the handler in the main thread like CPython does, interrupting any operation in progress