NAME

Mojo::IOWatcher - Non-blocking I/O watcher

SYNOPSIS

  use Mojo::IOWatcher;

  # Watch if handle becomes readable or writabe
  my $watcher = Mojo::IOWatcher->new;
  $watcher->io($handle => sub {
    my ($watcher, $handle, $writable) = @_;
    say $writable ? 'Handle is writable' : 'Handle is readable';
  });

  # Add a timer
  $watcher->timer(15 => sub {
    my $watcher = shift;
    $watcher->drop($handle);
    say 'Timeout!';
  });

  # Start and stop watcher
  $watcher->start;
  $watcher->stop;

DESCRIPTION

Mojo::IOWatcher is a minimalistic non-blocking I/O watcher and the foundation of Mojo::IOLoop. Mojo::IOWatcher::EV is a good example for its extensibility. Note that this module is EXPERIMENTAL and might change without warning!

EVENTS

Mojo::IOWatcher can emit the following events.

error

  $watcher->on(error => sub {
    my ($watcher, $err) = @_;
    ...
  });

Emitted safely if an error happens.

METHODS

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

detect

  my $class = Mojo::IOWatcher->detect;

Detect and load the best watcher implementation available, will try the value of the MOJO_IOWATCHER environment variable or Mojo::IOWatcher::EV.

drop

  my $success = $watcher->drop($handle);
  my $success = $watcher->drop($id);

Drop handle or timer.

io

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

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

is_readable

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

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

is_running

  my $success = $watcher->is_running;

Check if watcher is running.

recurring

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

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

start

  $watcher->start;

Start watching for I/O and timer events.

stop

  $watcher->stop;

Stop watching for I/O and timer events.

timer

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

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

watch

  $watcher = $watcher->watch($handle, $read, $write);

Change I/O events to watch handle for.

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

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

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

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

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.

cpanm Mojolicious

perl -MCPAN -e shell
install Mojolicious