def daemonize()

in scripts/cronjobs/pubsubber.py [0:0]

• 31 lines of code
• 5 McCabe index (conditional complexity)

        def daemonize(self):
                """Daemonize class. UNIX double fork mechanism."""

                try: 
                        pid = os.fork() 
                        if pid > 0:
                                # exit first parent
                                sys.exit(0) 
                except OSError as err: 
                        sys.stderr.write('fork #1 failed: {0}\n'.format(err))
                        sys.exit(1)
        
                # decouple from parent environment
                os.chdir('/') 
                os.setsid() 
                os.umask(0) 
        
                # do second fork
                try: 
                        pid = os.fork() 
                        if pid > 0:

                                # exit from second parent
                                sys.exit(0) 
                except OSError as err: 
                        sys.stderr.write('fork #2 failed: {0}\n'.format(err))
                        sys.exit(1) 
        
                # redirect standard file descriptors
                sys.stdout.flush()
                sys.stderr.flush()
                si = open(os.devnull, 'r')
                so = open(self.logfile, 'a+')
                se = open(self.logfile, 'a+')

                os.dup2(si.fileno(), sys.stdin.fileno())
                os.dup2(so.fileno(), sys.stdout.fileno())
                os.dup2(se.fileno(), sys.stderr.fileno())
        
                # write pidfile
                atexit.register(self.delpid)

                pid = str(os.getpid())
                with open(self.pidfile,'w+') as f:
                        f.write(pid + '\n')
                logger.info("Created %s", self.pidfile)