IO::Async::Timer::PeriUser(Contributed Perl DocumIO::Async::Timer::Periodic(3)NAME
"IO::Async::Timer::Periodic" - event callback at regular intervals
SYNOPSIS
use IO::Async::Timer::Periodic;
use IO::Async::Loop;
my $loop = IO::Async::Loop->new;
my $timer = IO::Async::Timer::Periodic->new(
interval => 60,
on_tick => sub {
print "You've had a minute\n";
},
);
$timer->start;
$loop->add( $timer );
$loop->run;
DESCRIPTION
This subclass of IO::Async::Timer implements repeating events at
regular clock intervals. The timing may or may not be subject to how
long it takes the callback to execute. Iterations may be rescheduled
runs at fixed regular intervals beginning at the time the timer was
started, or by a fixed delay after the previous code has finished
executing.
For a "Timer" object that only runs a callback once, after a given
delay, see instead IO::Async::Timer::Countdown. A Countdown timer can
also be used to create repeating events that fire at a fixed delay
after the previous event has finished processing. See als the examples
in "IO::Async::Timer::Countdown".
EVENTS
The following events are invoked, either using subclass methods or CODE
references in parameters:
on_tick
Invoked on each interval of the timer.
PARAMETERS
The following named parameters may be passed to "new" or "configure":
on_tick => CODE
CODE reference for the "on_tick" event.
interval => NUM
The interval in seconds between invocations of the callback or
method. Cannot be changed if the timer is running.
first_interval => NUM
Optional. If defined, the interval in seconds after calling the
"start" method before the first invocation of the callback or
method. Thereafter, the regular "interval" will be used. If not
supplied, the first interval will be the same as the others.
Even if this value is zero, the first invocation will be made
asynchronously, by the containing "Loop" object, and not
synchronously by the "start" method itself.
reschedule => STRING
Optional. Must be one of "hard", "skip" or "drift". Defines the
algorithm used to reschedule the next invocation.
"hard" schedules each iteration at the fixed interval from the
previous iteration's schedule time, ensuring a regular
repeating event.
"skip" schedules similarly to "hard", but skips over times that
have already passed. This matters if the duration is
particularly short and there's a possibility that times may be
missed, or if the entire process is stopped and resumed by
"SIGSTOP" or similar.
"drift" schedules each iteration at the fixed interval from the
time that the previous iteration's event handler returns. This
allows it to slowly drift over time and become desynchronised
with other events of the same interval or multiples/fractions
of it.
Once constructed, the timer object will need to be added to the "Loop"
before it will work. It will also need to be started by the "start"
method.
AUTHOR
Paul Evans <leonerd@leonerd.org.uk>
perl v5.18.2 2014-05-14 IO::Async::Timer::Periodic(3)
