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"