in reply to Re: Running multiple instances of a daemon simultaneously?
in thread Running multiple instances of a daemon simultaneously?

Yeah I guess I just wasn't firing on all cylinders yesterday; I'm not sure why I couldn't get it to work. I've run into a slightly different issue: the daemon doesn't return input control to the user. So for example the behavior of the script I borrowed from is:

[user@linux ~] perl original.pl --start

Starting...

[user@linux ~]

But my version hangs, like

[user@linux ~] perl original.pl --start

Starting...

and I have to ctrl-z before I can enter anything else

Here's my modified example daemon:

#!/usr/bin/perl use warnings; use strict; use Getopt::Long; use Proc::Daemon; use Cwd; use File::Spec::Functions; my $daemon = Proc::Daemon->new( work_dir => getcwd() ); my $pid; my $daemonize = 1; GetOptions( 'daemon!' => \$daemonize, "start" => \&run, "status" => \&status, "stop" => \&stop ); sub stop{ if($pid){ print "Stopping pid $pid... \n"; if($daemon->Kill_Daemon($pid)){ print "Successfully stopped. \n"; }else{ print "Could not find $pid. Was it running? \n"; } }else{ print "not Running, nothing to stop. \n"; } } sub status{ if($pid){ print "Running with pid $pid. \n"; }else{ print "Not running. \n"; } } sub run{ if (!$pid){ print "Starting...\n"; if($daemonize){ $pid = $daemon->Init; } while(1){ open(my $FH, '>>', catfile(getcwd(), "log.txt")); print $FH "Logging from PID $pid at " . time() . "\n"; close $FH; sleep 5; } }else{ print "No active daemons. \n"; } }
I've narrowed the problem down to the assignment $pid = $daemon->Init;

But removing the assignment obviously means the pid isn't stored. I guess I could just go with command line arguments.

EDIT: OR I could write a temp pid file, write to and then read from the file, and then destroy it.

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Re^3: Running multiple instances of a daemon simultaneously?
by roboticus (Chancellor) on Aug 08, 2014 at 15:01 UTC

    Trenin:

    Are you certain that it's $daemon->Init? The reason I ask is that immediately after doing that you enter an infinite loop, so I wouldn't expect you to get control again until you either put the job in the background or terminate it.

    ...roboticus

    When your only tool is a hammer, all problems look like your thumb.

      Sorry for the late reply. It did work for me; the job immediately goes into the background, and I can terminate it by killing the PID.