Event::group

📦 max

A group watcher: an event when none of its member watchers has run its callback for timeout seconds - a watchdog over a set of watchers.

use Event does not load this watcher type; use Event::group does (Event->group without it still works, with a warning that autoloading is deprecated).

Event->group(%attributes) (or Event::group->new(...)) takes the shared attributes of Event::Watcher, timeout, and any number of add => $watcher pairs; del there is ignored with a warning. A group repeats. It refuses to start without a callback, or without a timeout (“repeating group has no timeout”).

Synopsis

use Event;
use Event::group;

my $in  = Event->io(fd => \*STDIN, cb => \&read_input);
my $tick = Event->timer(interval => 5, cb => \&poll_server);
Event->group(add => $in, add => $tick, timeout => 60,
             cb => sub { warn "nothing happened for a minute\n" });
Event::loop();

Functions

Attributes

timeout

Seconds of silence after which the group fires: a number, or a reference to a number. A negative value warns and counts as 0; anything else that is not a number dies.

add

$group->add($watcher) makes $watcher a member; returns nothing. Adding the group to itself dies “can’t add group ‘DESC’ to itself”.

del

$group->del($watcher) removes a member; returns nothing. A watcher that is not a member is ignored.