NAME Async::Event::Interval - Extremely simple timed asynchronous events SYNOPSIS A simple event. Multiple events can be simultaneously used. For an example using an event that can share data with the main application, examples of how to handle event crashes, and how to send parameters to your event callback, see "EXAMPLES". use Async::Event::Interval; my $event = Async::Event::Interval->new( 1.5, \&callback ); $event->start; for (1..10){ print "$_: in main loop\n"; $event->stop if $_ == 3; $event->start if $_ == 7; if ($event->status){ print "event is running\n"; } if ($event->status == -1){ print "event has crashed... restarting it\n"; $event->restart; } sleep 1; } sub callback { print "timed event callback\n"; } DESCRIPTION Very basic implementation of asynchronous events that are triggered by a timed interval. Variables are not shared between the main application and the event. To do that, you'll need to use some form of memory sharing, such as IPC::Shareable. See "EXAMPLES" for an example. At this time, there is no real parameter passing or ability to return values. As I said... basic. Each event is simply a separate forked process, which runs in a while loop. METHODS new($delay, $callback) Returns a new Async::Event::Interval object. Does not create the event. Use start for that. Parameters: $delay Mandatory: The interval on which to trigger your event callback, in seconds. Represent partial seconds as a floating point number. $callback Mandatory: A reference to a subroutine that will be called every time the interval expires. start Starts the event timer. Each time the interval is reached, the event callback is executed. stop Stops the event from being executed. restart Alias for start(). Re-starts a stop()ped event. status Returns the event's process ID (true) if it is running, 0 (false) if it isn't, and -1 if the event has crashed. EXAMPLES Event Parameters You can send in a list of parameters to the event callback. Changing these within the main program will have no effect on the values sent into the event itself. use Async::Event::Interval my @params = qw(1 2 3); my $event = Async::Event::Interval->new( 1, \&callback, @params ); sub callback { my ($one, $two, $three) = @_; print "$one, $two, $three\n"; } Shared Data A timed event where the event callback shares a hash reference with the main program. use Async::Event::Interval; use IPC::Shareable; my $href = {a => 0, b => 1}; tie $href, 'IPC::Shareable', undef; my $event = Async::Event::Interval->new(10, \&callback); sub callback { $h->{a}++; } Event crash: Restart event use warnings; use strict; use feature 'say'; use Async::Event::Interval; my $event = Async::Event::Interval->new( 2, sub { kill 9, $$; }, ); $event->start; sleep 1; # do stuff if ($event->status == -1){ say "event crashed, restarting"; $event->restart; } Event crash: End program use warnings; use strict; use feature 'say'; use Async::Event::Interval; my $event = Async::Event::Interval->new( 2, sub { kill 9, $$; }, ); $event->start; sleep 1; # do stuff if ($event->status == -1){ say "event crashed, can't continue..."; exit; } AUTHOR Steve Bertrand, LICENSE AND COPYRIGHT Copyright 2017 Steve Bertrand. This program is free software; you can redistribute it and/or modify it under the terms of either: the GNU General Public License as published by the Free Software Foundation; or the Artistic License. See http://dev.perl.org/licenses/ for more information.