Re: [HTCondor-users] Trapping condor_hold in Python scripts on Windows

["John (TJ) Knoeller" <johnkn@xxxxxxxxxxx>]

Windows doesn't actually have signals, so HTCondor simulates them when 
talking to it's own daemons
by sending socket messages - so when the starter log on windows says 
'Got SIGTERM' it's lying.
what it really got was a daemon command message.

We can't do the same thing for jobs though, for windows jobs we send a 
WM_CLOSE message to the job.
So you want to somehow catch the WM_CLOSE in python and treat it like a 
SIGTERM.

I would imagine that this would involve somehow getting python to 
register a ConsoleControlHandler callback
https://msdn.microsoft.com/en-us/library/ms686016(VS.85).aspx

-tj

On 8/7/2015 2:16 PM, Ben Cotton wrote:
> Has anyone had any luck trapping when a Python script is placed on
> hold on Windows? My proof-of-concept script below works on Linux, but
> not on Windows, despite the fact that the starterlog suggests that it
> should:
>
> 08/07/15 14:53:10 (pid:7952) Got SIGTERM. Performing graceful shutdown.
>
> import os
> import signal
> import sys
> import time
>
> def cleanShutdown(signal, frame):
>      '''A method to handle shutdowns. This is necessary to prevent the agent from
>      hanging on a HTCondor shutdown, since the shutdown script sends SIGQUIT
>      instead of SIGTERM.'''
>
>      print 'Received signal %i, shutting down server' % signal
>      sys.exit(0)
>
> # Capture SIGINT and SIGQUIT
> signal.signal(signal.SIGINT,cleanShutdown)
> signal.signal(signal.SIGTERM,cleanShutdown)
> if os.name != 'nt':
>      signal.signal(signal.SIGQUIT,cleanShutdown)
>
> time.sleep(900)