NAME

       Sys::Virt::Event - An event loop contract

DESCRIPTION

       The "Sys::Virt::Event" module represents the contract for integrating libvirt with an event loop. This
       package is abstract and intended to be subclassed to provide an actual implementation.

METHODS

       register_default()
           Register the default libvirt event loop implementation

       run_default()
           Run a single iteration of the default event loop implementation

       register($impl)
           Register an event loop implementation. The implementation should be a instance of a sub-class of the
           "Sys::Virt::Event" package.

       $self->_run_handle_callback($watch, $fd, $events, $cb, $opaque)
           A helper method for executing a callback in response to one of more $events on the file handle $fd.
           The $watch number is the unique idenifier associated with the file descriptor. The $cb and $opaque
           parameters are the callback and data registered for the handle.

       $self->_run_timeout_callback($timer, $cb, $opaque)
           A helper method for executing a callback in response to the expiry of a timeout identified by $timer.
           The $cb and $opaque parameters are the callback and data registered for the timeout.

       $self->_free_callback_opaque($ff, $opaque)
           A helper method for freeing the data associated with a callback.  The $ff and $opaque parameters are
           the callback and data registered for the handle/timeout.

       my $watch = Sys::Virt::Event::add_handle($fd, $events, $coderef)
           Adds a watch on the file descriptor $fd for the events $events which is a mask of the FILE HANDLE
           EVENTS constants listed later.  The $coderef parameter is a subroutine to invoke when an event is
           triggered. The subroutine will be passed three parameters, the watch identifier, the file descriptor
           and the event mask. This method returns the watch identifier which can be used to update or remove
           the watch

       Sys::Virt::Event::update_handle($watch, $events)
           Update the event mask for the file descriptor watch $watch to use the events $events.

       Sys::Virt::Event::remove_handle($watch)
           Remove the event mask for the file descriptor watch $watch.

       my $watch = Sys::Virt::Event::add_timeout($frequency, $coderef)
           Adds a timeout to trigger with $frequency milliseconds interval.  The $coderef parameter is a
           subroutine to invoke when an event is triggered. The subroutine will be passed one parameter, the
           timer identifier. This method returns the watch identifier which can be used to update or remove the
           watch

       Sys::Virt::Event::update_timeout($timer, $frequency)
           Update the timeout $timer to have the frequency $frequency milliseconds.

       Sys::Virt::Event::remove_timeout($timer)
           Remove the timeout $timer

CONSTANTS

   FILE HANDLE EVENTS
       When integrating with an event loop the following constants define the file descriptor events

       Sys::Virt::Event::HANDLE_READABLE
           The file descriptor has data available for read without blocking

       Sys::Virt::Event::HANDLE_WRITABLE
           The file descriptor has ability to write data without blocking

       Sys::Virt::Event::HANDLE_ERROR
           An error occurred on the file descriptor

       Sys::Virt::Event::HANDLE_HANGUP
           The remote end of the file descriptor closed

AUTHORS

       Daniel P. Berrange <berrange@redhat.com>

COPYRIGHT

       Copyright (C) 2006-2009 Red Hat Copyright (C) 2006-2009 Daniel P. Berrange

LICENSE

       This program is free software; you can redistribute it and/or modify it under the terms of either the GNU
       General Public License as published by the Free Software Foundation (either version 2 of the License, or
       at your option any later version), or, the Artistic License, as specified in the Perl README file.

SEE ALSO

       Sys::Virt,  "http://libvirt.org"