vincent
01-20-2009 05:51 AM
Interesting to see the huge interest in Cloud Computing. David Luckham’s complexevents.com just referenced one of several recent Infoworld articles and blogs that attempt to define the term. Another compares the buzz to past excitements - remember Application Service... (0 Replies)
Sys::Virt::Event(3pm) User Contributed Perl Documentation Sys::Virt::Event(3pm)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"
perl v5.14.2 2012-05-21 Sys::Virt::Event(3pm)