NAME

       Linux::Epoll - O(1) multiplexing for Linux

VERSION

       version 0.012

SYNOPSIS

        use Linux::Epoll;

        my $epoll = Linux::Epoll->new();
        $epoll->add($fh, 'in', sub {
            my $events = shift;
            do_something($fh) if $events->{in};
        });
        $epoll->wait while 1;

DESCRIPTION

       Epoll is a multiplexing mechanism that scales up O(1) with number of watched files.
       Linux::Epoll is a callback style epoll module, unlike other epoll modules available on
       CPAN.

   Types of events
       •   in

           The associated filehandle is availible for reading.

       •   out

           The associated filehandle is availible for writing.

       •   err

           An error condition has happened on the associated filehandle. "wait" will always wait
           on this event, it is not necessary to set this with "add" or "modify".

       •   prio

           There is urgent data available for reading.

       •   et

           Set edge triggered behavior for the associated filehandle. The default behavior is
           level triggered. See you epoll(7) documentation for more information on what this
           means.

       •   hup

           A hang-up has happened on the associated filehandle. "wait" will always wait on this
           event, it is not necessary to set this with "add" or "modify".

       •   rdhup

           Stream socket peer closed the connection, or shut down the writing half of connection.
           This flag is especially useful for writing simple code to detect peer shutdown when
           using Edge Triggered monitoring.

       •   oneshot

           Sets the one-shot behavior for the associated file descriptor. This means that after
           an event is pulled out with "wait" the associated file descriptor is internally
           disabled and no other events will be reported by the epoll interface. The user must
           call "modify" to rearm the file descriptor with a new event mask.

METHODS

   new()
       Create a new epoll instance.

   add($fh, $events, $callback)
       Register the filehandle with the epoll instance and associate events $events and callback
       $callback with it. $events may be either a string (e.g. 'in') or an arrayref (e.g. "[qw/in
       out hup/]"). If a filehandle already exists in the set and "add" is called in non-void
       context, it returns undef and sets $! to "EEXIST"; if the file can't be waited upon it
       sets $! to "EPERM" instead. On all other error conditions an exception is thrown. The
       callback gets a single argument, a hashref whose keys are the triggered events.

   modify($fh, $events, $callback)
       Change the events and callback associated on this epoll instance with filehandle $fh. The
       arguments work the same as with "add". If a filehandle doesn't exist in the set and
       "modify" is called in non-void context, it returns undef and sets $! to "ENOENT". On all
       other error conditions an exception is thrown.

   delete($fh)
       Remove a filehandle from the epoll instance. If a filehandle doesn't exist in the set and
       "delete" is called in non-void context, it returns undef and sets $! to "ENOENT". On all
       other error conditions an exception is thrown.

   wait($number = 1, $timeout = undef, $sigmask = undef)
       Wait for up to $number events, where $number must be greater than zero. $timeout is the
       maximal time "wait" will wait for events in fractional seconds. If it is undefined it may
       wait indefinitely. $sigmask is the signal mask during the call. If it is not defined the
       signal mask will be untouched. If interrupted by a signal it returns undef/an empty list
       and sets $! to "EINTR". On all other error conditions an exception is thrown.

REQUIREMENTS

       This module requires at least Perl 5.10 and Linux 2.6.19 to function correctly.

SEE ALSO

       •   IO::Epoll

       •   Sys::Syscall

       •   IO::Poll

AUTHOR

       Leon Timmermans <leont@cpan.org>

COPYRIGHT AND LICENSE

       This software is copyright (c) 2010 by Leon Timmermans.

       This is free software; you can redistribute it and/or modify it under the same terms as
       the Perl 5 programming language system itself.