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NAME

Mojo::IOWatcher - Async IO Watcher

SYNOPSIS

  use Mojo::IOWatcher;

  # Watch if io handles become readable or writable
  my $watcher = Mojo::IOWatcher->new;
  $watcher->add($handle, on_readable => sub {
    my ($watcher, $handle) = @_;
    ...
  });

  # Use timers
  $watcher->timer(15 => sub {
    my $watcher = shift;
    $watcher->remove($handle);
    print "Timeout!\n";
  });

  # And loop!
  $watcher->one_tick('0.25') while 1;

DESCRIPTION

Mojo::IOWatcher is a minimalistic async io watcher and the foundation of Mojo::IOLoop. Mojo::IOWatcher::KQueue and Mojo::IOWatcher::Epoll are good examples for its extensibility. Note that this module is EXPERIMENTAL and might change without warning!

METHODS

Mojo::IOWatcher inherits all methods from Mojo::Base and implements the following new ones.

add

  $watcher = $watcher->add($handle, on_readable => sub {...});

Add handles and watch for io events.

These options are currently available:

on_readable

Callback to be invoked once the handle becomes readable.

on_writable

Callback to be invoked once the handle becomes writable.

cancel

  my $success = $watcher->cancel($id);

Cancel timer.

is_readable

  my $readable = $watcher->is_readable($handle);

Quick check if a handle is readable, useful for identifying tainted sockets.

not_writing

  $watcher = $watcher->not_writing($handle);

Only watch handle for readable events.

one_tick

  $watcher->one_tick('0.25');

Run for exactly one tick and watch for io and timer events.

recurring

  my $id = $watcher->recurring(3 => sub {...});

Create a new recurring timer, invoking the callback repeatedly after a given amount of seconds.

remove

  $watcher = $watcher->remove($handle);

Remove handle.

timer

  my $id = $watcher->timer(3 => sub {...});

Create a new timer, invoking the callback after a given amount of seconds.

watch

  $watcher->watch('0.25');

Run for exactly one tick and watch only for io events.

writing

  $watcher = $watcher->writing($handle);

Watch handle for readable and writable events.

DEBUGGING

You can set the MOJO_IOWATCHER_DEBUG environment variable to get some advanced diagnostics information printed to STDERR.

  MOJO_IOWATCHER_DEBUG=1

SEE ALSO

Mojolicious, Mojolicious::Guides, http://mojolicio.us.