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anyevent::impl::ioasync(3pm) [debian man page]

AnyEvent::Impl::IOAsync(3pm)				User Contributed Perl Documentation			      AnyEvent::Impl::IOAsync(3pm)

NAME
AnyEvent::Impl::IOAsync - AnyEvent adaptor for IO::Async SYNOPSIS
use AnyEvent; use IO::Async::Loop; # optionally set another event loop use AnyEvent::Impl::IOAsync; my $loop = new IO::Async::Loop; AnyEvent::Impl::IOAsync::set_loop $loop; DESCRIPTION
This module provides support for IO::Async as AnyEvent backend. It supports I/O, timers, signals and child process watchers. Idle watchers are emulated. I/O watchers need to dup their fh because IO::Async only supports IO handles, not plain file descriptors. PROBLEMS WITH IO
::Async This section had a long list of problems and shortcomings that made it almost impossible to support IO::Async. With version 0.33 of IO::Async, however, most of these have been fixed, so IO::Async can now be used as easily as many other loops. There are a few remaining problems that require emulation or workarounds: No support for multiple watchers per event In most (all? documentation?) cases you cannot have multiple watchers for the same event (what's the point of having all these fancy notifier classes when you cannot have multiple notifiers for the same event? That's like only allowing one timer per second or so...). For I/O watchers, AnyEvent has to dup() every file handle, as IO::Async fails to support the same or different file handles pointing to the same fd (the good thing is that it is documented, but why not fix it instead?). Apart from these fatal flaws, there are a number of unpleasent properties that just need some mentioning: Confusing and misleading names Another rather negative point about this module family is its name, which is deeply confusing: Despite the "async" in the name, IO::Async only does synchronous I/O, there is nothing "asynchronous" about it whatsoever (when I first heard about it, I thought, "wow, a second async I/O module, what does it do compared to IO::AIO", and was somehow set back when I learned that the only "async" aspect of it is the name). Inconsistent, incomplete and convoluted API Implementing AnyEvent's rather simple timers on top of IO::Async's timers was a nightmare (try implementing a timer with configurable interval and delay value...). The method naming is chaotic: "watch_child" creates a child watcher, but "watch_io" is an internal method; "detach_signal" removes a signal watcher, but "detach_child" forks a subprocess and so on). Unpleasant surprises on GNU/Linux When you develop your program on FreeBSD and run it on GNU/Linux, you might have unpleasant surprises, as IO::Async::Loop will by default use IO::Async::Loop::Epoll, which is incompatible with "fork", so your network server will run into spurious and very hard to debug problems under heavy load, as IO::Async forks a lot of processes, e.g. for DNS resolution. It would be better if IO::Async would only load "safe" backends by default (or fix the epoll backend to work in the presence of fork, which admittedly is hard - EV does it for you, and also does not use unsafe backends by default). On the positive side, performance with IO::Async is quite good even in my very demanding eyes. SEE ALSO
AnyEvent, IO::Async. AUTHOR
Marc Lehmann <schmorp@schmorp.de> http://anyevent.schmorp.de Paul Evans <leonerd@leonerd.org.uk> Rewrote the backend for IO::Async version 0.33. perl v5.14.2 2012-04-08 AnyEvent::Impl::IOAsync(3pm)

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IO::Async::Loop::Glib(3pm)				User Contributed Perl Documentation				IO::Async::Loop::Glib(3pm)

NAME
"IO::Async::Loop::Glib" - use "IO::Async" with Glib or GTK SYNOPSIS
use IO::Async::Loop::Glib; my $loop = IO::Async::Loop::Glib->new(); $loop->add( ... ); ... # Rest of GLib/Gtk program that uses GLib Glib::MainLoop->new->run(); Or $loop->loop_forever(); Or while(1) { $loop->loop_once(); } DESCRIPTION
This subclass of "IO::Async::Loop" uses the "Glib::MainLoop" to perform read-ready and write-ready tests. The appropriate "Glib::IO" sources are added or removed from the "Glib::MainLoop" when notifiers are added or removed from the set, or when they change their "want_writeready" status. The callbacks are called automatically by Glib itself; no special methods on this loop object are required. CONSTRUCTOR
$loop = IO::Async::Loop::Glib->new() This function returns a new instance of a "IO::Async::Loop::Glib" object. It takes no special arguments. METHODS
There are no special methods in this subclass, other than those provided by the "IO::Async::Loop" base class. $count = $loop->loop_once( $timeout ) This method calls the "iteration()" method on the underlying "Glib::MainContext". If a timeout value is supplied, then a Glib timeout will be installed, to interrupt the loop at that time. If Glib indicates that any callbacks were fired, then this method will return 1 (however, it does not mean that any "IO::Async" callbacks were invoked, as there may be other parts of code sharing the Glib main context. Otherwise, it will return 0. SEE ALSO
o Glib - Perl wrappers for the GLib utility and Object libraries o Gtk2 - Perl interface to the 2.x series of the Gimp Toolkit library AUTHOR
Paul Evans <leonerd@leonerd.org.uk> perl v5.14.2 2013-03-01 IO::Async::Loop::Glib(3pm)
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