When I call $_[KERNEL]->alarm() twice referencing two events from within an event that itself is called by $_[KERNEL]->alarm().

_start -> (alarm to wakeup event). wakeup event -> ( alarms to wokeup event and wakeup event). This works as I would expect.

When I call the alarm to wakeup before the alarm to wokeup, the wokeup event is never called.

works: 

#!/usr/bin/perl

use strict;
use warnings;

use POE;

use Time::HiRes qw(time);

POE::Session->create
  ( inline_states =>
      { _start => sub {
            $_[KERNEL]->alias_set('timer');
            $_[KERNEL]->post('timer', 'wakeup');
        },

        wakeup => sub {
            print "wakeup at ", scalar localtime(), "\n";
            $[KERNEL]->alarm( wokeup => int( time() ) + 2 );
            $[KERNEL]->alarm( wakeup => int( time() ) + 2 );
        },

        wokeup => sub {
            print "wokeup at ", scalar localtime(), "\n";
        },
      },
  );

POE::Kernel->run();
exit 0;

[download]
jason@jfroebe-laptop:~/bin$ ./test_poe.pl
wakeup at Tue Jul  1 20:30:56 2008
wokeup at Tue Jul  1 20:30:58 2008
wakeup at Tue Jul  1 20:30:58 2008
wokeup at Tue Jul  1 20:31:00 2008

[download]

wokeup is never called: 

#!/usr/bin/perl

use strict;
use warnings;

use POE;

use Time::HiRes qw(time);

POE::Session->create
  ( inline_states =>
      { _start => sub {
            $_[KERNEL]->alias_set('timer');
            $_[KERNEL]->post('timer', 'wakeup');
        },

        wakeup => sub {
            print "wakeup at ", scalar localtime(), "\n";
            $_[KERNEL]->alarm( wakeup => int( time() ) + 2 );
            $_[KERNEL]->alarm( wokeup => int( time() ) + 2 );
        },

        wokeup => sub {
            print "wokeup at ", scalar localtime(), "\n";
        },
      },
  );

POE::Kernel->run();
exit 0;

[download]
jason@jfroebe-laptop:~/bin$ ./test_poe.pl
wakeup at Tue Jul  1 19:36:29 2008
wakeup at Tue Jul  1 19:36:31 2008
wakeup at Tue Jul  1 19:36:33 2008

[download]

My understanding is that $_[KERNEL]->alarm() sets the alarm and moves on. Apparently it isn't when the alarm is set to the event that it is currently in. That, or I'm misunderstanding $_[KERNEL]->alarm(). Am I close?

Jason L. Froebe

Blog, Tech Blog

In reply to POE::Session - why does alarm order matter? by jfroebe

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