NAME
IO::Async::Loop::Epoll - use IO::Async with epoll on Linux
SYNOPSIS
use IO::Async::Loop::Epoll;
use IO::Async::Stream;
use IO::Async::Signal;
my $loop = IO::Async::Loop::Epoll->new;
$loop->add( IO::Async::Stream->new(
read_handle => \*STDIN,
on_read => sub {
my ( $self, $buffref ) = @_;
while( $$buffref =~ s/^(.*)\r?\n// ) {
print "You said: $1\n";
}
},
) );
$loop->add( IO::Async::Signal->new(
name => 'INT',
on_receipt => sub {
print "SIGINT, will now quit\n";
$loop->stop;
},
) );
$loop->run;
DESCRIPTION
This subclass of IO::Async::Loop uses epoll(7) on Linux to perform
read-ready and write-ready tests so that the O(1) high-performance
multiplexing of Linux's epoll_pwait(2) syscall can be used.
The epoll Linux subsystem uses a persistent registration system,
meaning that better performance can be achieved in programs using a
large number of filehandles. Each epoll_pwait(2) syscall only has an
overhead proportional to the number of ready filehandles, rather than
the total number being watched. For more detail, see the epoll(7)
manpage.
This class uses the epoll_pwait(2) system call, which atomically
switches the process's signal mask, performs a wait exactly as
epoll_wait(2) would, then switches it back. This allows a process to
block the signals it cares about, but switch in an empty signal mask
during the poll, allowing it to handle file IO and signals
concurrently.
CONSTRUCTOR
new
$loop = IO::Async::Loop::Epoll->new()
This function returns a new instance of a IO::Async::Loop::Epoll
object.
METHODS
As this is a subclass of IO::Async::Loop, all of its methods are
inherited. Expect where noted below, all of the class's methods behave
identically to IO::Async::Loop.
loop_once
$count = $loop->loop_once( $timeout )
This method calls epoll_pwait(2), and processes the results of that
call. It returns the total number of IO::Async::Notifier callbacks
invoked, or undef if the underlying epoll_pwait() method returned an
error. If the epoll_pwait() was interrupted by a signal, then 0 is
returned instead.
SEE ALSO
* Linux::Epoll - O(1) multiplexing for Linux
* IO::Async::Loop::Poll - use IO::Async with poll(2)
AUTHOR
Paul Evans <leonerd@leonerd.org.uk>