Using variables in signal handler - require global?

Question

I have a signal handler to handle ctrl-c interrupt. If in the signal handler I want to read a variable set in my main script, is there an alternative to using a \"global\" s

Answer 1

Within the object-oriented paradigm (OOP) it's quite convenient to use lambdas for that purpose. Using lambdas you could pass some additional context (like a self reference) and/or get rid of the unused arguments (signal, frame).

import time
import signal

class Application:

    def __init__( self ):
        signal.signal( signal.SIGINT, lambda signal, frame: self._signal_handler() )
        self.terminated = False

    def _signal_handler( self ):
        self.terminated = True

    def MainLoop( self ):        
        while not self.terminated:
            print( "I'm just doing my job like everyone else" )
            time.sleep( 3 )

app = Application()
app.MainLoop()

print( "The app is terminated, exiting ..." )