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Mojolicious-2.11
River stage four • 1014 direct dependents • 1136 total dependents
/ Mojo::IOWatcher

NAME

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

SYNOPSIS


            

              
              
use Mojo::IOWatcher;
# Watch if I/O 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);
  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!

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 I/O 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.

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.

is_readable


            

              
              
my $success = $watcher->is_readable($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.

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.

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.

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.