Mojo::...OAsync(3pm)

💅 NAME 💅

okay bestie, this manual page is for Mojo::Reactor::IOAsync — the IO::Async backend for Mojo::Reactor. It’s giving “same reactor vibes, different engine” and honestly? iconic. ✨

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✨ SYNOPSIS ✨

use Mojo::Reactor::IOAsync;

# Watch if handle becomes readable or writable
my $reactor = Mojo::Reactor::IOAsync->new;
$reactor->io($first => sub {
  my ($reactor, $writable) = @_;
  say $writable ? 'First handle is writable' : 'First handle is readable';
});

# Change to watching only if handle becomes writable
$reactor->watch($first, 0, 1);

# Turn file descriptor into handle and watch if it becomes readable
my $second = IO::Handle->new_from_fd($fd, 'r');
$reactor->io($second => sub {
  my ($reactor, $writable) = @_;
  say $writable ? 'Second handle is writable' : 'Second handle is readable';
})->watch($second, 1, 0);

# Add a timer
$reactor->timer(15 => sub {
  my $reactor = shift;
  $reactor->remove($first);
  $reactor->remove($second);
  say 'Timeout!';
});

# Start reactor if necessary
$reactor->start unless $reactor->is_running;

# Or in an application using Mojo::IOLoop
use Mojo::Reactor::IOAsync;
use Mojo::IOLoop;

# Or in a Mojolicious application
$ MOJO_REACTOR=Mojo::Reactor::IOAsync hypnotoad script/myapp

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💖 DESCRIPTION 💖

Mojo::Reactor::IOAsync is an event reactor for Mojo::IOLoop that uses IO::Async. The usage is exactly the same as other Mojo::Reactor implementations such as Mojo::Reactor::Poll — so no cap, same moves, different backend 💅.

Mojo::Reactor::IOAsync will be used as the default backend for Mojo::IOLoop if it is loaded before Mojo::IOLoop or any module using the loop. However, when invoking a Mojolicious application through morbo or hypnotoad, the reactor must be set as the default by setting the MOJO_REACTOR environment variable to Mojo::Reactor::IOAsync. periodt.

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🌈 EVENTS 🌈

Mojo::Reactor::IOAsync inherits all events from Mojo::Reactor::Poll. No extra event lore, bestie — it’s all inherited 🫶.

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💅 METHODS 💅

Mojo::Reactor::IOAsync inherits all methods from Mojo::Reactor::Poll and implements the following new ones. Main character method list incoming 🔥.

🎀 new 🎀

my $reactor = Mojo::Reactor::IOAsync->new;

Construct a new Mojo::Reactor::IOAsync object. Fresh reactor, fresh vibes ✨.

🎀 again 🎀

$reactor->again($id);
$reactor->again($id, 0.5);

Restart timer and optionally change the invocation time. Note that this method requires an active timer — so don’t try it on a timer that’s not, like, currently doing its thing 🙈.

🎀 io 🎀

$reactor = $reactor->io($handle => sub {...});

Watch handle for I/O events, invoking the callback whenever handle becomes readable or writable.

# Callback will be invoked twice if handle becomes readable and writable
$reactor->io($handle => sub {
  my ($reactor, $writable) = @_;
  say $writable ? 'Handle is writable' : 'Handle is readable';
});

🎀 one_tick 🎀

$reactor->one_tick;

Run reactor until an event occurs or no events are being watched anymore. See CAVEATS — yes bestie, peek down there 👀.

# Don't block longer than 0.5 seconds
my $id = $reactor->timer(0.5 => sub {});
$reactor->one_tick;
$reactor->remove($id);

🎀 recurring 🎀

my $id = $reactor->recurring(0.25 => sub {...});

Create a new recurring timer, invoking the callback repeatedly after a given amount of time in seconds. It’s the timer that keeps on timering 🔁.

🎀 remove 🎀

my $bool = $reactor->remove($handle);
my $bool = $reactor->remove($id);

Remove handle or timer. bye bye, watcher 🫡.

🎀 reset 🎀

$reactor->reset;

Remove all handles and timers. Clean slate, no crumbs, we love to see it 💖.

🎀 stop 🎀

$reactor->stop;

Stop watching for I/O and timer events. reactor said “I’m clocking out” 💀.

🎀 timer 🎀

my $id = $reactor->timer(0.5 => sub {...});

Create a new timer, invoking the callback after a given amount of time in seconds. one-shot timer, very demure, very mindful ⏳.

🎀 watch 🎀

$reactor = $reactor->watch($handle, $readable, $writable);

Change I/O events to watch handle for with true and false values. Note that this method requires an active I/O watcher — so it’s not out here watching nothing, okay? 💅

# Watch only for readable events
$reactor->watch($handle, 1, 0);

# Watch only for writable events
$reactor->watch($handle, 0, 1);

# Watch for readable and writable events
$reactor->watch($handle, 1, 1);

# Pause watching for events
$reactor->watch($handle, 0, 0);

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⚠️ CAVEATS ⚠️

When using Mojo::IOLoop with IO::Async, the event loop must be controlled by Mojo::IOLoop or Mojo::Reactor::IOAsync, such as with the methods start in Mojo::Reactor::Poll, stop, and one_tick. Starting or stopping the event loop through IO::Async will not provide required functionality to Mojo::IOLoop applications. so like… don’t hand the aux cord to the wrong loop, bestie 😭.

Externally-added IO::Async notifiers will keep the Mojo::IOLoop loop running if they are added to the event loop as a notifier, see NOTIFIER MANAGEMENT in IO::Async::Loop. iykyk.

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🐛 BUGS 🐛

Report any issues on the public bugtracker. if it’s busted, tell the bugtracker, not the group chat 🫶.

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👑 AUTHOR 👑

Dan Book, dbook@cpan.org

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🎀 COPYRIGHT AND LICENSE 🎀

Copyright 2015, Dan Book.

This library is free software; you may redistribute it and/or modify it under the terms of the Artistic License version 2.0.

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🦋 SEE ALSO 🦋

• Mojolicious
• Mojo::IOLoop
• IO::Async

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okay that’s the page, bestie! footer tea: perl v5.42.2 💫 dated 2026-02-15 🎀 — bye! 💖✨