bionic (3) Linux::Epoll.3pm.gz

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.