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Revision 1.296 by root, Tue Nov 17 01:19:49 2009 UTC

1	=head1 NAME	1	=head1 NAME
2		2
3	AnyEvent - provide framework for multiple event loops	3	AnyEvent - the DBI of event loop programming
4		4
5	EV, Event, Glib, Tk, Perl, Event::Lib, Qt and POE are various supported	5	EV, Event, Glib, Tk, Perl, Event::Lib, Irssi, rxvt-unicode, IO::Async, Qt
6	event loops.	6	and POE are various supported event loops/environments.
7		7
8	=head1 SYNOPSIS	8	=head1 SYNOPSIS
9		9
10	use AnyEvent;	10	use AnyEvent;
11		11
…		…
40	=head1 INTRODUCTION/TUTORIAL	40	=head1 INTRODUCTION/TUTORIAL
41		41
42	This manpage is mainly a reference manual. If you are interested	42	This manpage is mainly a reference manual. If you are interested
43	in a tutorial or some gentle introduction, have a look at the	43	in a tutorial or some gentle introduction, have a look at the
44	L<AnyEvent::Intro> manpage.	44	L<AnyEvent::Intro> manpage.
		45
		46	=head1 SUPPORT
		47
		48	There is a mailinglist for discussing all things AnyEvent, and an IRC
		49	channel, too.
		50
		51	See the AnyEvent project page at the B<Schmorpforge Ta-Sa Software
		52	Repository>, at L<http://anyevent.schmorp.de>, for more info.
45		53
46	=head1 WHY YOU SHOULD USE THIS MODULE (OR NOT)	54	=head1 WHY YOU SHOULD USE THIS MODULE (OR NOT)
47		55
48	Glib, POE, IO::Async, Event... CPAN offers event models by the dozen	56	Glib, POE, IO::Async, Event... CPAN offers event models by the dozen
49	nowadays. So what is different about AnyEvent?	57	nowadays. So what is different about AnyEvent?
…		…
173	my variables are only visible after the statement in which they are	181	my variables are only visible after the statement in which they are
174	declared.	182	declared.
175		183
176	=head2 I/O WATCHERS	184	=head2 I/O WATCHERS
177		185
		186	$w = AnyEvent->io (
		187	fh => <filehandle_or_fileno>,
		188	poll => <"r" or "w">,
		189	cb => <callback>,
		190	);
		191
178	You can create an I/O watcher by calling the C<< AnyEvent->io >> method	192	You can create an I/O watcher by calling the C<< AnyEvent->io >> method
179	with the following mandatory key-value pairs as arguments:	193	with the following mandatory key-value pairs as arguments:
180		194
181	C<fh> is the Perl I<file handle> (I<not> file descriptor) to watch	195	C<fh> is the Perl I<file handle> (or a naked file descriptor) to watch
182	for events (AnyEvent might or might not keep a reference to this file	196	for events (AnyEvent might or might not keep a reference to this file
183	handle). Note that only file handles pointing to things for which	197	handle). Note that only file handles pointing to things for which
184	non-blocking operation makes sense are allowed. This includes sockets,	198	non-blocking operation makes sense are allowed. This includes sockets,
185	most character devices, pipes, fifos and so on, but not for example files	199	most character devices, pipes, fifos and so on, but not for example files
186	or block devices.	200	or block devices.
…		…
211	undef $w;	225	undef $w;
212	});	226	});
213		227
214	=head2 TIME WATCHERS	228	=head2 TIME WATCHERS
215		229
		230	$w = AnyEvent->timer (after => <seconds>, cb => <callback>);
		231
		232	$w = AnyEvent->timer (
		233	after => <fractional_seconds>,
		234	interval => <fractional_seconds>,
		235	cb => <callback>,
		236	);
		237
216	You can create a time watcher by calling the C<< AnyEvent->timer >>	238	You can create a time watcher by calling the C<< AnyEvent->timer >>
217	method with the following mandatory arguments:	239	method with the following mandatory arguments:
218		240
219	C<after> specifies after how many seconds (fractional values are	241	C<after> specifies after how many seconds (fractional values are
220	supported) the callback should be invoked. C<cb> is the callback to invoke	242	supported) the callback should be invoked. C<cb> is the callback to invoke
…		…
341	might affect timers and time-outs.	363	might affect timers and time-outs.
342		364
343	When this is the case, you can call this method, which will update the	365	When this is the case, you can call this method, which will update the
344	event loop's idea of "current time".	366	event loop's idea of "current time".
345		367
		368	A typical example would be a script in a web server (e.g. C<mod_perl>) -
		369	when mod_perl executes the script, then the event loop will have the wrong
		370	idea about the "current time" (being potentially far in the past, when the
		371	script ran the last time). In that case you should arrange a call to C<<
		372	AnyEvent->now_update >> each time the web server process wakes up again
		373	(e.g. at the start of your script, or in a handler).
		374
346	Note that updating the time I<might> cause some events to be handled.	375	Note that updating the time I<might> cause some events to be handled.
347		376
348	=back	377	=back
349		378
350	=head2 SIGNAL WATCHERS	379	=head2 SIGNAL WATCHERS
		380
		381	$w = AnyEvent->signal (signal => <uppercase_signal_name>, cb => <callback>);
351		382
352	You can watch for signals using a signal watcher, C<signal> is the signal	383	You can watch for signals using a signal watcher, C<signal> is the signal
353	I<name> in uppercase and without any C<SIG> prefix, C<cb> is the Perl	384	I<name> in uppercase and without any C<SIG> prefix, C<cb> is the Perl
354	callback to be invoked whenever a signal occurs.	385	callback to be invoked whenever a signal occurs.
355		386
…		…
361	invocation, and callback invocation will be synchronous. Synchronous means	392	invocation, and callback invocation will be synchronous. Synchronous means
362	that it might take a while until the signal gets handled by the process,	393	that it might take a while until the signal gets handled by the process,
363	but it is guaranteed not to interrupt any other callbacks.	394	but it is guaranteed not to interrupt any other callbacks.
364		395
365	The main advantage of using these watchers is that you can share a signal	396	The main advantage of using these watchers is that you can share a signal
366	between multiple watchers.	397	between multiple watchers, and AnyEvent will ensure that signals will not
		398	interrupt your program at bad times.
367		399
368	This watcher might use C<%SIG>, so programs overwriting those signals	400	This watcher might use C<%SIG> (depending on the event loop used),
369	directly will likely not work correctly.	401	so programs overwriting those signals directly will likely not work
		402	correctly.
370		403
371	Example: exit on SIGINT	404	Example: exit on SIGINT
372		405
373	my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });	406	my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
374		407
		408	=head3 Signal Races, Delays and Workarounds
		409
		410	Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching
		411	callbacks to signals in a generic way, which is a pity, as you cannot
		412	do race-free signal handling in perl, requiring C libraries for
		413	this. AnyEvent will try to do it's best, which means in some cases,
		414	signals will be delayed. The maximum time a signal might be delayed is
		415	specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This
		416	variable can be changed only before the first signal watcher is created,
		417	and should be left alone otherwise. This variable determines how often
		418	AnyEvent polls for signals (in case a wake-up was missed). Higher values
		419	will cause fewer spurious wake-ups, which is better for power and CPU
		420	saving.
		421
		422	All these problems can be avoided by installing the optional
		423	L<Async::Interrupt> module, which works with most event loops. It will not
		424	work with inherently broken event loops such as L<Event> or L<Event::Lib>
		425	(and not with L<POE> currently, as POE does it's own workaround with
		426	one-second latency). For those, you just have to suffer the delays.
		427
375	=head2 CHILD PROCESS WATCHERS	428	=head2 CHILD PROCESS WATCHERS
376		429
		430	$w = AnyEvent->child (pid => <process id>, cb => <callback>);
		431
377	You can also watch on a child process exit and catch its exit status.	432	You can also watch on a child process exit and catch its exit status.
378		433
379	The child process is specified by the C<pid> argument (if set to C<0>, it	434	The child process is specified by the C<pid> argument (one some backends,
380	watches for any child process exit). The watcher will triggered only when	435	using C<0> watches for any child process exit, on others this will
381	the child process has finished and an exit status is available, not on	436	croak). The watcher will be triggered only when the child process has
382	any trace events (stopped/continued).	437	finished and an exit status is available, not on any trace events
		438	(stopped/continued).
383		439
384	The callback will be called with the pid and exit status (as returned by	440	The callback will be called with the pid and exit status (as returned by
385	waitpid), so unlike other watcher types, you I<can> rely on child watcher	441	waitpid), so unlike other watcher types, you I<can> rely on child watcher
386	callback arguments.	442	callback arguments.
387		443
…		…
403		459
404	This means you cannot create a child watcher as the very first	460	This means you cannot create a child watcher as the very first
405	thing in an AnyEvent program, you I<have> to create at least one	461	thing in an AnyEvent program, you I<have> to create at least one
406	watcher before you C<fork> the child (alternatively, you can call	462	watcher before you C<fork> the child (alternatively, you can call
407	C<AnyEvent::detect>).	463	C<AnyEvent::detect>).
		464
		465	As most event loops do not support waiting for child events, they will be
		466	emulated by AnyEvent in most cases, in which the latency and race problems
		467	mentioned in the description of signal watchers apply.
408		468
409	Example: fork a process and wait for it	469	Example: fork a process and wait for it
410		470
411	my $done = AnyEvent->condvar;	471	my $done = AnyEvent->condvar;
412		472
…		…
424	# do something else, then wait for process exit	484	# do something else, then wait for process exit
425	$done->recv;	485	$done->recv;
426		486
427	=head2 IDLE WATCHERS	487	=head2 IDLE WATCHERS
428		488
		489	$w = AnyEvent->idle (cb => <callback>);
		490
429	Sometimes there is a need to do something, but it is not so important	491	Sometimes there is a need to do something, but it is not so important
430	to do it instantly, but only when there is nothing better to do. This	492	to do it instantly, but only when there is nothing better to do. This
431	"nothing better to do" is usually defined to be "no other events need	493	"nothing better to do" is usually defined to be "no other events need
432	attention by the event loop".	494	attention by the event loop".
433		495
…		…
459	});	521	});
460	});	522	});
461		523
462	=head2 CONDITION VARIABLES	524	=head2 CONDITION VARIABLES
463		525
		526	$cv = AnyEvent->condvar;
		527
		528	$cv->send (<list>);
		529	my @res = $cv->recv;
		530
464	If you are familiar with some event loops you will know that all of them	531	If you are familiar with some event loops you will know that all of them
465	require you to run some blocking "loop", "run" or similar function that	532	require you to run some blocking "loop", "run" or similar function that
466	will actively watch for new events and call your callbacks.	533	will actively watch for new events and call your callbacks.
467		534
468	AnyEvent is different, it expects somebody else to run the event loop and	535	AnyEvent is slightly different: it expects somebody else to run the event
469	will only block when necessary (usually when told by the user).	536	loop and will only block when necessary (usually when told by the user).
470		537
471	The instrument to do that is called a "condition variable", so called	538	The instrument to do that is called a "condition variable", so called
472	because they represent a condition that must become true.	539	because they represent a condition that must become true.
473		540
		541	Now is probably a good time to look at the examples further below.
		542
474	Condition variables can be created by calling the C<< AnyEvent->condvar	543	Condition variables can be created by calling the C<< AnyEvent->condvar
475	>> method, usually without arguments. The only argument pair allowed is	544	>> method, usually without arguments. The only argument pair allowed is
476
477	C<cb>, which specifies a callback to be called when the condition variable	545	C<cb>, which specifies a callback to be called when the condition variable
478	becomes true, with the condition variable as the first argument (but not	546	becomes true, with the condition variable as the first argument (but not
479	the results).	547	the results).
480		548
481	After creation, the condition variable is "false" until it becomes "true"	549	After creation, the condition variable is "false" until it becomes "true"
…		…
486	Condition variables are similar to callbacks, except that you can	554	Condition variables are similar to callbacks, except that you can
487	optionally wait for them. They can also be called merge points - points	555	optionally wait for them. They can also be called merge points - points
488	in time where multiple outstanding events have been processed. And yet	556	in time where multiple outstanding events have been processed. And yet
489	another way to call them is transactions - each condition variable can be	557	another way to call them is transactions - each condition variable can be
490	used to represent a transaction, which finishes at some point and delivers	558	used to represent a transaction, which finishes at some point and delivers
491	a result.	559	a result. And yet some people know them as "futures" - a promise to
		560	compute/deliver something that you can wait for.
492		561
493	Condition variables are very useful to signal that something has finished,	562	Condition variables are very useful to signal that something has finished,
494	for example, if you write a module that does asynchronous http requests,	563	for example, if you write a module that does asynchronous http requests,
495	then a condition variable would be the ideal candidate to signal the	564	then a condition variable would be the ideal candidate to signal the
496	availability of results. The user can either act when the callback is	565	availability of results. The user can either act when the callback is
…		…
530	after => 1,	599	after => 1,
531	cb => sub { $result_ready->send },	600	cb => sub { $result_ready->send },
532	);	601	);
533		602
534	# this "blocks" (while handling events) till the callback	603	# this "blocks" (while handling events) till the callback
535	# calls send	604	# calls ->send
536	$result_ready->recv;	605	$result_ready->recv;
537		606
538	Example: wait for a timer, but take advantage of the fact that	607	Example: wait for a timer, but take advantage of the fact that condition
539	condition variables are also code references.	608	variables are also callable directly.
540		609
541	my $done = AnyEvent->condvar;	610	my $done = AnyEvent->condvar;
542	my $delay = AnyEvent->timer (after => 5, cb => $done);	611	my $delay = AnyEvent->timer (after => 5, cb => $done);
543	$done->recv;	612	$done->recv;
544		613
…		…
550		619
551	...	620	...
552		621
553	my @info = $couchdb->info->recv;	622	my @info = $couchdb->info->recv;
554		623
555	And this is how you would just ste a callback to be called whenever the	624	And this is how you would just set a callback to be called whenever the
556	results are available:	625	results are available:
557		626
558	$couchdb->info->cb (sub {	627	$couchdb->info->cb (sub {
559	my @info = $_[0]->recv;	628	my @info = $_[0]->recv;
560	});	629	});
…		…
578	immediately from within send.	647	immediately from within send.
579		648
580	Any arguments passed to the C<send> call will be returned by all	649	Any arguments passed to the C<send> call will be returned by all
581	future C<< ->recv >> calls.	650	future C<< ->recv >> calls.
582		651
583	Condition variables are overloaded so one can call them directly	652	Condition variables are overloaded so one can call them directly (as if
584	(as a code reference). Calling them directly is the same as calling	653	they were a code reference). Calling them directly is the same as calling
585	C<send>. Note, however, that many C-based event loops do not handle	654	C<send>.
586	overloading, so as tempting as it may be, passing a condition variable
587	instead of a callback does not work. Both the pure perl and EV loops
588	support overloading, however, as well as all functions that use perl to
589	invoke a callback (as in L<AnyEvent::Socket> and L<AnyEvent::DNS> for
590	example).
591		655
592	=item $cv->croak ($error)	656	=item $cv->croak ($error)
593		657
594	Similar to send, but causes all call's to C<< ->recv >> to invoke	658	Similar to send, but causes all call's to C<< ->recv >> to invoke
595	C<Carp::croak> with the given error message/object/scalar.	659	C<Carp::croak> with the given error message/object/scalar.
596		660
597	This can be used to signal any errors to the condition variable	661	This can be used to signal any errors to the condition variable
598	user/consumer.	662	user/consumer. Doing it this way instead of calling C<croak> directly
		663	delays the error detetcion, but has the overwhelmign advantage that it
		664	diagnoses the error at the place where the result is expected, and not
		665	deep in some event clalback without connection to the actual code causing
		666	the problem.
599		667
600	=item $cv->begin ([group callback])	668	=item $cv->begin ([group callback])
601		669
602	=item $cv->end	670	=item $cv->end
603		671
…		…
605	one. For example, a function that pings many hosts in parallel might want	673	one. For example, a function that pings many hosts in parallel might want
606	to use a condition variable for the whole process.	674	to use a condition variable for the whole process.
607		675
608	Every call to C<< ->begin >> will increment a counter, and every call to	676	Every call to C<< ->begin >> will increment a counter, and every call to
609	C<< ->end >> will decrement it. If the counter reaches C<0> in C<< ->end	677	C<< ->end >> will decrement it. If the counter reaches C<0> in C<< ->end
610	>>, the (last) callback passed to C<begin> will be executed. That callback	678	>>, the (last) callback passed to C<begin> will be executed, passing the
611	is I<supposed> to call C<< ->send >>, but that is not required. If no	679	condvar as first argument. That callback is I<supposed> to call C<< ->send
612	callback was set, C<send> will be called without any arguments.	680	>>, but that is not required. If no group callback was set, C<send> will
		681	be called without any arguments.
613		682
614	You can think of C<< $cv->send >> giving you an OR condition (one call	683	You can think of C<< $cv->send >> giving you an OR condition (one call
615	sends), while C<< $cv->begin >> and C<< $cv->end >> giving you an AND	684	sends), while C<< $cv->begin >> and C<< $cv->end >> giving you an AND
616	condition (all C<begin> calls must be C<end>'ed before the condvar sends).	685	condition (all C<begin> calls must be C<end>'ed before the condvar sends).
617		686
…		…
644	begung can potentially be zero:	713	begung can potentially be zero:
645		714
646	my $cv = AnyEvent->condvar;	715	my $cv = AnyEvent->condvar;
647		716
648	my %result;	717	my %result;
649	$cv->begin (sub { $cv->send (\%result) });	718	$cv->begin (sub { shift->send (\%result) });
650		719
651	for my $host (@list_of_hosts) {	720	for my $host (@list_of_hosts) {
652	$cv->begin;	721	$cv->begin;
653	ping_host_then_call_callback $host, sub {	722	ping_host_then_call_callback $host, sub {
654	$result{$host} = ...;	723	$result{$host} = ...;
…		…
699	function will call C<croak>.	768	function will call C<croak>.
700		769
701	In list context, all parameters passed to C<send> will be returned,	770	In list context, all parameters passed to C<send> will be returned,
702	in scalar context only the first one will be returned.	771	in scalar context only the first one will be returned.
703		772
		773	Note that doing a blocking wait in a callback is not supported by any
		774	event loop, that is, recursive invocation of a blocking C<< ->recv
		775	>> is not allowed, and the C<recv> call will C<croak> if such a
		776	condition is detected. This condition can be slightly loosened by using
		777	L<Coro::AnyEvent>, which allows you to do a blocking C<< ->recv >> from
		778	any thread that doesn't run the event loop itself.
		779
704	Not all event models support a blocking wait - some die in that case	780	Not all event models support a blocking wait - some die in that case
705	(programs might want to do that to stay interactive), so I<if you are	781	(programs might want to do that to stay interactive), so I<if you are
706	using this from a module, never require a blocking wait>, but let the	782	using this from a module, never require a blocking wait>. Instead, let the
707	caller decide whether the call will block or not (for example, by coupling	783	caller decide whether the call will block or not (for example, by coupling
708	condition variables with some kind of request results and supporting	784	condition variables with some kind of request results and supporting
709	callbacks so the caller knows that getting the result will not block,	785	callbacks so the caller knows that getting the result will not block,
710	while still supporting blocking waits if the caller so desires).	786	while still supporting blocking waits if the caller so desires).
711		787
712	Another reason I<never> to C<< ->recv >> in a module is that you cannot
713	sensibly have two C<< ->recv >>'s in parallel, as that would require
714	multiple interpreters or coroutines/threads, none of which C<AnyEvent>
715	can supply.
716
717	The L<Coro> module, however, I<can> and I<does> supply coroutines and, in
718	fact, L<Coro::AnyEvent> replaces AnyEvent's condvars by coroutine-safe
719	versions and also integrates coroutines into AnyEvent, making blocking
720	C<< ->recv >> calls perfectly safe as long as they are done from another
721	coroutine (one that doesn't run the event loop).
722
723	You can ensure that C<< -recv >> never blocks by setting a callback and	788	You can ensure that C<< -recv >> never blocks by setting a callback and
724	only calling C<< ->recv >> from within that callback (or at a later	789	only calling C<< ->recv >> from within that callback (or at a later
725	time). This will work even when the event loop does not support blocking	790	time). This will work even when the event loop does not support blocking
726	waits otherwise.	791	waits otherwise.
727		792
…		…
733	=item $cb = $cv->cb ($cb->($cv))	798	=item $cb = $cv->cb ($cb->($cv))
734		799
735	This is a mutator function that returns the callback set and optionally	800	This is a mutator function that returns the callback set and optionally
736	replaces it before doing so.	801	replaces it before doing so.
737		802
738	The callback will be called when the condition becomes "true", i.e. when	803	The callback will be called when the condition becomes (or already was)
739	C<send> or C<croak> are called, with the only argument being the condition	804	"true", i.e. when C<send> or C<croak> are called (or were called), with
740	variable itself. Calling C<recv> inside the callback or at any later time	805	the only argument being the condition variable itself. Calling C<recv>
741	is guaranteed not to block.	806	inside the callback or at any later time is guaranteed not to block.
742		807
743	=back	808	=back
744		809
		810	=head1 SUPPORTED EVENT LOOPS/BACKENDS
		811
		812	The available backend classes are (every class has its own manpage):
		813
		814	=over 4
		815
		816	=item Backends that are autoprobed when no other event loop can be found.
		817
		818	EV is the preferred backend when no other event loop seems to be in
		819	use. If EV is not installed, then AnyEvent will fall back to its own
		820	pure-perl implementation, which is available everywhere as it comes with
		821	AnyEvent itself.
		822
		823	AnyEvent::Impl::EV based on EV (interface to libev, best choice).
		824	AnyEvent::Impl::Perl pure-perl implementation, fast and portable.
		825
		826	=item Backends that are transparently being picked up when they are used.
		827
		828	These will be used when they are currently loaded when the first watcher
		829	is created, in which case it is assumed that the application is using
		830	them. This means that AnyEvent will automatically pick the right backend
		831	when the main program loads an event module before anything starts to
		832	create watchers. Nothing special needs to be done by the main program.
		833
		834	AnyEvent::Impl::Event based on Event, very stable, few glitches.
		835	AnyEvent::Impl::Glib based on Glib, slow but very stable.
		836	AnyEvent::Impl::Tk based on Tk, very broken.
		837	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
		838	AnyEvent::Impl::POE based on POE, very slow, some limitations.
		839	AnyEvent::Impl::Irssi used when running within irssi.
		840
		841	=item Backends with special needs.
		842
		843	Qt requires the Qt::Application to be instantiated first, but will
		844	otherwise be picked up automatically. As long as the main program
		845	instantiates the application before any AnyEvent watchers are created,
		846	everything should just work.
		847
		848	AnyEvent::Impl::Qt based on Qt.
		849
		850	Support for IO::Async can only be partial, as it is too broken and
		851	architecturally limited to even support the AnyEvent API. It also
		852	is the only event loop that needs the loop to be set explicitly, so
		853	it can only be used by a main program knowing about AnyEvent. See
		854	L<AnyEvent::Impl::Async> for the gory details.
		855
		856	AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed.
		857
		858	=item Event loops that are indirectly supported via other backends.
		859
		860	Some event loops can be supported via other modules:
		861
		862	There is no direct support for WxWidgets (L<Wx>) or L<Prima>.
		863
		864	B<WxWidgets> has no support for watching file handles. However, you can
		865	use WxWidgets through the POE adaptor, as POE has a Wx backend that simply
		866	polls 20 times per second, which was considered to be too horrible to even
		867	consider for AnyEvent.
		868
		869	B<Prima> is not supported as nobody seems to be using it, but it has a POE
		870	backend, so it can be supported through POE.
		871
		872	AnyEvent knows about both L<Prima> and L<Wx>, however, and will try to
		873	load L<POE> when detecting them, in the hope that POE will pick them up,
		874	in which case everything will be automatic.
		875
		876	=back
		877
745	=head1 GLOBAL VARIABLES AND FUNCTIONS	878	=head1 GLOBAL VARIABLES AND FUNCTIONS
746		879
		880	These are not normally required to use AnyEvent, but can be useful to
		881	write AnyEvent extension modules.
		882
747	=over 4	883	=over 4
748		884
749	=item $AnyEvent::MODEL	885	=item $AnyEvent::MODEL
750		886
751	Contains C<undef> until the first watcher is being created. Then it	887	Contains C<undef> until the first watcher is being created, before the
		888	backend has been autodetected.
		889
752	contains the event model that is being used, which is the name of the	890	Afterwards it contains the event model that is being used, which is the
753	Perl class implementing the model. This class is usually one of the	891	name of the Perl class implementing the model. This class is usually one
754	C<AnyEvent::Impl:xxx> modules, but can be any other class in the case	892	of the C<AnyEvent::Impl:xxx> modules, but can be any other class in the
755	AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode>).	893	case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it
756		894	will be C<urxvt::anyevent>).
757	The known classes so far are:
758
759	AnyEvent::Impl::EV based on EV (an interface to libev, best choice).
760	AnyEvent::Impl::Event based on Event, second best choice.
761	AnyEvent::Impl::Perl pure-perl implementation, fast and portable.
762	AnyEvent::Impl::Glib based on Glib, third-best choice.
763	AnyEvent::Impl::Tk based on Tk, very bad choice.
764	AnyEvent::Impl::Qt based on Qt, cannot be autoprobed (see its docs).
765	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
766	AnyEvent::Impl::POE based on POE, not generic enough for full support.
767
768	# warning, support for IO::Async is only partial, as it is too broken
769	# and limited toe ven support the AnyEvent API. See AnyEvent::Impl::Async.
770	AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed (see its docs).
771
772	There is no support for WxWidgets, as WxWidgets has no support for
773	watching file handles. However, you can use WxWidgets through the
774	POE Adaptor, as POE has a Wx backend that simply polls 20 times per
775	second, which was considered to be too horrible to even consider for
776	AnyEvent. Likewise, other POE backends can be used by AnyEvent by using
777	it's adaptor.
778
779	AnyEvent knows about L<Prima> and L<Wx> and will try to use L<POE> when
780	autodetecting them.
781		895
782	=item AnyEvent::detect	896	=item AnyEvent::detect
783		897
784	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model	898	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model
785	if necessary. You should only call this function right before you would	899	if necessary. You should only call this function right before you would
786	have created an AnyEvent watcher anyway, that is, as late as possible at	900	have created an AnyEvent watcher anyway, that is, as late as possible at
787	runtime.	901	runtime, and not e.g. while initialising of your module.
		902
		903	If you need to do some initialisation before AnyEvent watchers are
		904	created, use C<post_detect>.
788		905
789	=item $guard = AnyEvent::post_detect { BLOCK }	906	=item $guard = AnyEvent::post_detect { BLOCK }
790		907
791	Arranges for the code block to be executed as soon as the event model is	908	Arranges for the code block to be executed as soon as the event model is
792	autodetected (or immediately if this has already happened).	909	autodetected (or immediately if this has already happened).
793		910
		911	The block will be executed I<after> the actual backend has been detected
		912	(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been
		913	created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do
		914	other initialisations - see the sources of L<AnyEvent::Strict> or
		915	L<AnyEvent::AIO> to see how this is used.
		916
		917	The most common usage is to create some global watchers, without forcing
		918	event module detection too early, for example, L<AnyEvent::AIO> creates
		919	and installs the global L<IO::AIO> watcher in a C<post_detect> block to
		920	avoid autodetecting the event module at load time.
		921
794	If called in scalar or list context, then it creates and returns an object	922	If called in scalar or list context, then it creates and returns an object
795	that automatically removes the callback again when it is destroyed. See	923	that automatically removes the callback again when it is destroyed (or
		924	C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for
796	L<Coro::BDB> for a case where this is useful.	925	a case where this is useful.
		926
		927	Example: Create a watcher for the IO::AIO module and store it in
		928	C<$WATCHER>. Only do so after the event loop is initialised, though.
		929
		930	our WATCHER;
		931
		932	my $guard = AnyEvent::post_detect {
		933	$WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb);
		934	};
		935
		936	# the ||= is important in case post_detect immediately runs the block,
		937	# as to not clobber the newly-created watcher. assigning both watcher and
		938	# post_detect guard to the same variable has the advantage of users being
		939	# able to just C<undef $WATCHER> if the watcher causes them grief.
		940
		941	$WATCHER ||= $guard;
797		942
798	=item @AnyEvent::post_detect	943	=item @AnyEvent::post_detect
799		944
800	If there are any code references in this array (you can C<push> to it	945	If there are any code references in this array (you can C<push> to it
801	before or after loading AnyEvent), then they will called directly after	946	before or after loading AnyEvent), then they will called directly after
802	the event loop has been chosen.	947	the event loop has been chosen.
803		948
804	You should check C<$AnyEvent::MODEL> before adding to this array, though:	949	You should check C<$AnyEvent::MODEL> before adding to this array, though:
805	if it contains a true value then the event loop has already been detected,	950	if it is defined then the event loop has already been detected, and the
806	and the array will be ignored.	951	array will be ignored.
807		952
808	Best use C<AnyEvent::post_detect { BLOCK }> instead.	953	Best use C<AnyEvent::post_detect { BLOCK }> when your application allows
		954	it,as it takes care of these details.
		955
		956	This variable is mainly useful for modules that can do something useful
		957	when AnyEvent is used and thus want to know when it is initialised, but do
		958	not need to even load it by default. This array provides the means to hook
		959	into AnyEvent passively, without loading it.
809		960
810	=back	961	=back
811		962
812	=head1 WHAT TO DO IN A MODULE	963	=head1 WHAT TO DO IN A MODULE
813		964
…		…
868		1019
869		1020
870	=head1 OTHER MODULES	1021	=head1 OTHER MODULES
871		1022
872	The following is a non-exhaustive list of additional modules that use	1023	The following is a non-exhaustive list of additional modules that use
873	AnyEvent and can therefore be mixed easily with other AnyEvent modules	1024	AnyEvent as a client and can therefore be mixed easily with other AnyEvent
874	in the same program. Some of the modules come with AnyEvent, some are	1025	modules and other event loops in the same program. Some of the modules
875	available via CPAN.	1026	come with AnyEvent, most are available via CPAN.
876		1027
877	=over 4	1028	=over 4
878		1029
879	=item L<AnyEvent::Util>	1030	=item L<AnyEvent::Util>
880		1031
…		…
889		1040
890	=item L<AnyEvent::Handle>	1041	=item L<AnyEvent::Handle>
891		1042
892	Provide read and write buffers, manages watchers for reads and writes,	1043	Provide read and write buffers, manages watchers for reads and writes,
893	supports raw and formatted I/O, I/O queued and fully transparent and	1044	supports raw and formatted I/O, I/O queued and fully transparent and
894	non-blocking SSL/TLS.	1045	non-blocking SSL/TLS (via L<AnyEvent::TLS>.
895		1046
896	=item L<AnyEvent::DNS>	1047	=item L<AnyEvent::DNS>
897		1048
898	Provides rich asynchronous DNS resolver capabilities.	1049	Provides rich asynchronous DNS resolver capabilities.
899		1050
…		…
927		1078
928	=item L<AnyEvent::GPSD>	1079	=item L<AnyEvent::GPSD>
929		1080
930	A non-blocking interface to gpsd, a daemon delivering GPS information.	1081	A non-blocking interface to gpsd, a daemon delivering GPS information.
931		1082
		1083	=item L<AnyEvent::IRC>
		1084
		1085	AnyEvent based IRC client module family (replacing the older Net::IRC3).
		1086
		1087	=item L<AnyEvent::XMPP>
		1088
		1089	AnyEvent based XMPP (Jabber protocol) module family (replacing the older
		1090	Net::XMPP2>.
		1091
932	=item L<AnyEvent::IGS>	1092	=item L<AnyEvent::IGS>
933		1093
934	A non-blocking interface to the Internet Go Server protocol (used by	1094	A non-blocking interface to the Internet Go Server protocol (used by
935	L<App::IGS>).	1095	L<App::IGS>).
936		1096
937	=item L<AnyEvent::IRC>
938
939	AnyEvent based IRC client module family (replacing the older Net::IRC3).
940
941	=item L<Net::XMPP2>
942
943	AnyEvent based XMPP (Jabber protocol) module family.
944
945	=item L<Net::FCP>	1097	=item L<Net::FCP>
946		1098
947	AnyEvent-based implementation of the Freenet Client Protocol, birthplace	1099	AnyEvent-based implementation of the Freenet Client Protocol, birthplace
948	of AnyEvent.	1100	of AnyEvent.
949		1101
…		…
953		1105
954	=item L<Coro>	1106	=item L<Coro>
955		1107
956	Has special support for AnyEvent via L<Coro::AnyEvent>.	1108	Has special support for AnyEvent via L<Coro::AnyEvent>.
957		1109
958	=item L<IO::Lambda>
959
960	The lambda approach to I/O - don't ask, look there. Can use AnyEvent.
961
962	=back	1110	=back
963		1111
964	=cut	1112	=cut
965		1113
966	package AnyEvent;	1114	package AnyEvent;
967		1115
968	no warnings;	1116	# basically a tuned-down version of common::sense
		1117	sub common_sense {
		1118	# from common:.sense 1.0
		1119	${^WARNING_BITS} = "\xfc\x3f\xf3\x00\x0f\xf3\xcf\xc0\xf3\xfc\x33\x03";
969	use strict qw(vars subs);	1120	# use strict vars subs
		1121	$^H |= 0x00000600;
		1122	}
970		1123
		1124	BEGIN { AnyEvent::common_sense }
		1125
971	use Carp;	1126	use Carp ();
972		1127
973	our $VERSION = 4.42;	1128	our $VERSION = '5.202';
974	our $MODEL;	1129	our $MODEL;
975		1130
976	our $AUTOLOAD;	1131	our $AUTOLOAD;
977	our @ISA;	1132	our @ISA;
978		1133
979	our @REGISTRY;	1134	our @REGISTRY;
980		1135
981	our $WIN32;	1136	our $WIN32;
		1137
		1138	our $VERBOSE;
982		1139
983	BEGIN {	1140	BEGIN {
984	eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }";	1141	eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }";
985	eval "sub TAINT(){ " . (${^TAINT}*1) . " }";	1142	eval "sub TAINT(){ " . (${^TAINT}*1) . " }";
986		1143
987	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}	1144	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}
988	if ${^TAINT};	1145	if ${^TAINT};
989	}
990		1146
991	our $verbose = $ENV{PERL_ANYEVENT_VERBOSE}*1;	1147	$VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1;
		1148
		1149	}
		1150
		1151	our $MAX_SIGNAL_LATENCY = 10;
992		1152
993	our %PROTOCOL; # (ipv4|ipv6) => (1|2), higher numbers are preferred	1153	our %PROTOCOL; # (ipv4|ipv6) => (1|2), higher numbers are preferred
994		1154
995	{	1155	{
996	my $idx;	1156	my $idx;
…		…
998	for reverse split /\s*,\s*/,	1158	for reverse split /\s*,\s*/,
999	$ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6";	1159	$ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6";
1000	}	1160	}
1001		1161
1002	my @models = (	1162	my @models = (
1003	[EV:: => AnyEvent::Impl::EV::],	1163	[EV:: => AnyEvent::Impl::EV:: , 1],
1004	[Event:: => AnyEvent::Impl::Event::],
1005	[AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::],	1164	[AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl:: , 1],
1006	# everything below here will not be autoprobed	1165	# everything below here will not (normally) be autoprobed
1007	# as the pureperl backend should work everywhere	1166	# as the pureperl backend should work everywhere
1008	# and is usually faster	1167	# and is usually faster
		1168	[Event:: => AnyEvent::Impl::Event::, 1],
		1169	[Glib:: => AnyEvent::Impl::Glib:: , 1], # becomes extremely slow with many watchers
		1170	[Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
		1171	[Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package
1009	[Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles	1172	[Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
1010	[Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers
1011	[Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
1012	[Qt:: => AnyEvent::Impl::Qt::], # requires special main program	1173	[Qt:: => AnyEvent::Impl::Qt::], # requires special main program
1013	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza	1174	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
1014	[Wx:: => AnyEvent::Impl::POE::],	1175	[Wx:: => AnyEvent::Impl::POE::],
1015	[Prima:: => AnyEvent::Impl::POE::],	1176	[Prima:: => AnyEvent::Impl::POE::],
1016	# IO::Async is just too broken - we would need workaorunds for its	1177	# IO::Async is just too broken - we would need workarounds for its
1017	# byzantine signal and broken child handling, among others.	1178	# byzantine signal and broken child handling, among others.
1018	# IO::Async is rather hard to detect, as it doesn't have any	1179	# IO::Async is rather hard to detect, as it doesn't have any
1019	# obvious default class.	1180	# obvious default class.
1020	# [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program	1181	[IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program
1021	# [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program	1182	[IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program
1022	# [IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program	1183	[IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program
		1184	[AnyEvent::Impl::IOAsync:: => AnyEvent::Impl::IOAsync::], # requires special main program
1023	);	1185	);
1024		1186
1025	our %method = map +($_ => 1),	1187	our %method = map +($_ => 1),
1026	qw(io timer time now now_update signal child idle condvar one_event DESTROY);	1188	qw(io timer time now now_update signal child idle condvar one_event DESTROY);
1027		1189
…		…
1031	my ($cb) = @_;	1193	my ($cb) = @_;
1032		1194
1033	if ($MODEL) {	1195	if ($MODEL) {
1034	$cb->();	1196	$cb->();
1035		1197
1036	1	1198	undef
1037	} else {	1199	} else {
1038	push @post_detect, $cb;	1200	push @post_detect, $cb;
1039		1201
1040	defined wantarray	1202	defined wantarray
1041	? bless \$cb, "AnyEvent::Util::postdetect"	1203	? bless \$cb, "AnyEvent::Util::postdetect"
…		…
1047	@post_detect = grep $_ != ${$_[0]}, @post_detect;	1209	@post_detect = grep $_ != ${$_[0]}, @post_detect;
1048	}	1210	}
1049		1211
1050	sub detect() {	1212	sub detect() {
1051	unless ($MODEL) {	1213	unless ($MODEL) {
1052	no strict 'refs';
1053	local $SIG{__DIE__};	1214	local $SIG{__DIE__};
1054		1215
1055	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {	1216	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {
1056	my $model = "AnyEvent::Impl::$1";	1217	my $model = "AnyEvent::Impl::$1";
1057	if (eval "require $model") {	1218	if (eval "require $model") {
1058	$MODEL = $model;	1219	$MODEL = $model;
1059	warn "AnyEvent: loaded model '$model' (forced by \$PERL_ANYEVENT_MODEL), using it.\n" if $verbose > 1;	1220	warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2;
1060	} else {	1221	} else {
1061	warn "AnyEvent: unable to load model '$model' (from \$PERL_ANYEVENT_MODEL):\n$@" if $verbose;	1222	warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE;
1062	}	1223	}
1063	}	1224	}
1064		1225
1065	# check for already loaded models	1226	# check for already loaded models
1066	unless ($MODEL) {	1227	unless ($MODEL) {
1067	for (@REGISTRY, @models) {	1228	for (@REGISTRY, @models) {
1068	my ($package, $model) = @$_;	1229	my ($package, $model) = @$_;
1069	if (${"$package\::VERSION"} > 0) {	1230	if (${"$package\::VERSION"} > 0) {
1070	if (eval "require $model") {	1231	if (eval "require $model") {
1071	$MODEL = $model;	1232	$MODEL = $model;
1072	warn "AnyEvent: autodetected model '$model', using it.\n" if $verbose > 1;	1233	warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2;
1073	last;	1234	last;
1074	}	1235	}
1075	}	1236	}
1076	}	1237	}
1077		1238
1078	unless ($MODEL) {	1239	unless ($MODEL) {
1079	# try to load a model	1240	# try to autoload a model
1080
1081	for (@REGISTRY, @models) {	1241	for (@REGISTRY, @models) {
1082	my ($package, $model) = @$_;	1242	my ($package, $model, $autoload) = @$_;
		1243	if (
		1244	$autoload
1083	if (eval "require $package"	1245	and eval "require $package"
1084	and ${"$package\::VERSION"} > 0	1246	and ${"$package\::VERSION"} > 0
1085	and eval "require $model") {	1247	and eval "require $model"
		1248	) {
1086	$MODEL = $model;	1249	$MODEL = $model;
1087	warn "AnyEvent: autoprobed model '$model', using it.\n" if $verbose > 1;	1250	warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2;
1088	last;	1251	last;
1089	}	1252	}
1090	}	1253	}
1091		1254
1092	$MODEL	1255	$MODEL
…		…
1108		1271
1109	sub AUTOLOAD {	1272	sub AUTOLOAD {
1110	(my $func = $AUTOLOAD) =~ s/.*://;	1273	(my $func = $AUTOLOAD) =~ s/.*://;
1111		1274
1112	$method{$func}	1275	$method{$func}
1113	or croak "$func: not a valid method for AnyEvent objects";	1276	or Carp::croak "$func: not a valid method for AnyEvent objects";
1114		1277
1115	detect unless $MODEL;	1278	detect unless $MODEL;
1116		1279
1117	my $class = shift;	1280	my $class = shift;
1118	$class->$func (@_);	1281	$class->$func (@_);
…		…
1123	# allow only one watcher per fd, so we dup it to get a different one).	1286	# allow only one watcher per fd, so we dup it to get a different one).
1124	sub _dupfh($$;$$) {	1287	sub _dupfh($$;$$) {
1125	my ($poll, $fh, $r, $w) = @_;	1288	my ($poll, $fh, $r, $w) = @_;
1126		1289
1127	# cygwin requires the fh mode to be matching, unix doesn't	1290	# cygwin requires the fh mode to be matching, unix doesn't
1128	my ($rw, $mode) = $poll eq "r" ? ($r, "<")	1291	my ($rw, $mode) = $poll eq "r" ? ($r, "<&") : ($w, ">&");
1129	: $poll eq "w" ? ($w, ">")
1130	: Carp::croak "AnyEvent->io requires poll set to either 'r' or 'w'";
1131		1292
1132	open my $fh2, "$mode&" . fileno $fh	1293	open my $fh2, $mode, $fh
1133	or die "cannot dup() filehandle: $!,";	1294	or die "AnyEvent->io: cannot dup() filehandle in mode '$poll': $!,";
1134		1295
1135	# we assume CLOEXEC is already set by perl in all important cases	1296	# we assume CLOEXEC is already set by perl in all important cases
1136		1297
1137	($fh2, $rw)	1298	($fh2, $rw)
1138	}	1299	}
1139		1300
		1301	=head1 SIMPLIFIED AE API
		1302
		1303	Starting with version 5.0, AnyEvent officially supports a second, much
		1304	simpler, API that is designed to reduce the calling, typing and memory
		1305	overhead.
		1306
		1307	See the L<AE> manpage for details.
		1308
		1309	=cut
		1310
		1311	package AE;
		1312
		1313	our $VERSION = $AnyEvent::VERSION;
		1314
		1315	sub io($$$) {
		1316	AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])
		1317	}
		1318
		1319	sub timer($$$) {
		1320	AnyEvent->timer (after => $_[0], interval => $_[1], cb => $_[2])
		1321	}
		1322
		1323	sub signal($$) {
		1324	AnyEvent->signal (signal => $_[0], cb => $_[1])
		1325	}
		1326
		1327	sub child($$) {
		1328	AnyEvent->child (pid => $_[0], cb => $_[1])
		1329	}
		1330
		1331	sub idle($) {
		1332	AnyEvent->idle (cb => $_[0])
		1333	}
		1334
		1335	sub cv(;&) {
		1336	AnyEvent->condvar (@_ ? (cb => $_[0]) : ())
		1337	}
		1338
		1339	sub now() {
		1340	AnyEvent->now
		1341	}
		1342
		1343	sub now_update() {
		1344	AnyEvent->now_update
		1345	}
		1346
		1347	sub time() {
		1348	AnyEvent->time
		1349	}
		1350
1140	package AnyEvent::Base;	1351	package AnyEvent::Base;
1141		1352
1142	# default implementations for many methods	1353	# default implementations for many methods
1143		1354
1144	BEGIN {	1355	sub _time() {
		1356	# probe for availability of Time::HiRes
1145	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {	1357	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
		1358	warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8;
1146	*_time = \&Time::HiRes::time;	1359	*_time = \&Time::HiRes::time;
1147	# if (eval "use POSIX (); (POSIX::times())...	1360	# if (eval "use POSIX (); (POSIX::times())...
1148	} else {	1361	} else {
		1362	warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE;
1149	*_time = sub { time }; # epic fail	1363	*_time = sub { time }; # epic fail
1150	}	1364	}
		1365
		1366	&_time
1151	}	1367	}
1152		1368
1153	sub time { _time }	1369	sub time { _time }
1154	sub now { _time }	1370	sub now { _time }
1155	sub now_update { }	1371	sub now_update { }
…		…
1160	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"	1376	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"
1161	}	1377	}
1162		1378
1163	# default implementation for ->signal	1379	# default implementation for ->signal
1164		1380
		1381	our $HAVE_ASYNC_INTERRUPT;
		1382
		1383	sub _have_async_interrupt() {
		1384	$HAVE_ASYNC_INTERRUPT = 1*(!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT}
		1385	&& eval "use Async::Interrupt 1.02 (); 1")
		1386	unless defined $HAVE_ASYNC_INTERRUPT;
		1387
		1388	$HAVE_ASYNC_INTERRUPT
		1389	}
		1390
1165	our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);	1391	our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);
		1392	our (%SIG_ASY, %SIG_ASY_W);
		1393	our ($SIG_COUNT, $SIG_TW);
1166		1394
1167	sub _signal_exec {	1395	sub _signal_exec {
		1396	$HAVE_ASYNC_INTERRUPT
		1397	? $SIGPIPE_R->drain
1168	sysread $SIGPIPE_R, my $dummy, 4;	1398	: sysread $SIGPIPE_R, (my $dummy), 9;
1169		1399
1170	while (%SIG_EV) {	1400	while (%SIG_EV) {
1171	for (keys %SIG_EV) {	1401	for (keys %SIG_EV) {
1172	delete $SIG_EV{$_};	1402	delete $SIG_EV{$_};
1173	$_->() for values %{ $SIG_CB{$_} || {} };	1403	$_->() for values %{ $SIG_CB{$_} || {} };
1174	}	1404	}
1175	}	1405	}
1176	}	1406	}
1177		1407
		1408	# install a dummy wakeup watcher to reduce signal catching latency
		1409	sub _sig_add() {
		1410	unless ($SIG_COUNT++) {
		1411	# try to align timer on a full-second boundary, if possible
		1412	my $NOW = AE::now;
		1413
		1414	$SIG_TW = AE::timer
		1415	$MAX_SIGNAL_LATENCY - ($NOW - int $NOW),
		1416	$MAX_SIGNAL_LATENCY,
		1417	sub { } # just for the PERL_ASYNC_CHECK
		1418	;
		1419	}
		1420	}
		1421
		1422	sub _sig_del {
		1423	undef $SIG_TW
		1424	unless --$SIG_COUNT;
		1425	}
		1426
		1427	our $_sig_name_init; $_sig_name_init = sub {
		1428	eval q{ # poor man's autoloading
		1429	undef $_sig_name_init;
		1430
		1431	if (_have_async_interrupt) {
		1432	*sig2num = \&Async::Interrupt::sig2num;
		1433	*sig2name = \&Async::Interrupt::sig2name;
		1434	} else {
		1435	require Config;
		1436
		1437	my %signame2num;
		1438	@signame2num{ split ' ', $Config::Config{sig_name} }
		1439	= split ' ', $Config::Config{sig_num};
		1440
		1441	my @signum2name;
		1442	@signum2name[values %signame2num] = keys %signame2num;
		1443
		1444	*sig2num = sub($) {
		1445	$_[0] > 0 ? shift : $signame2num{+shift}
		1446	};
		1447	*sig2name = sub ($) {
		1448	$_[0] > 0 ? $signum2name[+shift] : shift
		1449	};
		1450	}
		1451	};
		1452	die if $@;
		1453	};
		1454
		1455	sub sig2num ($) { &$_sig_name_init; &sig2num }
		1456	sub sig2name($) { &$_sig_name_init; &sig2name }
		1457
1178	sub signal {	1458	sub signal {
1179	my (undef, %arg) = @_;	1459	eval q{ # poor man's autoloading {}
		1460	# probe for availability of Async::Interrupt
		1461	if (_have_async_interrupt) {
		1462	warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8;
1180		1463
1181	unless ($SIGPIPE_R) {	1464	$SIGPIPE_R = new Async::Interrupt::EventPipe;
1182	require Fcntl;	1465	$SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;
1183		1466
1184	if (AnyEvent::WIN32) {
1185	require AnyEvent::Util;
1186
1187	($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
1188	AnyEvent::Util::fh_nonblocking ($SIGPIPE_R) if $SIGPIPE_R;
1189	AnyEvent::Util::fh_nonblocking ($SIGPIPE_W) if $SIGPIPE_W; # just in case
1190	} else {	1467	} else {
		1468	warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;
		1469
		1470	require Fcntl;
		1471
		1472	if (AnyEvent::WIN32) {
		1473	require AnyEvent::Util;
		1474
		1475	($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
		1476	AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R;
		1477	AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case
		1478	} else {
1191	pipe $SIGPIPE_R, $SIGPIPE_W;	1479	pipe $SIGPIPE_R, $SIGPIPE_W;
1192	fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R;	1480	fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R;
1193	fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case	1481	fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case
1194		1482
1195	# not strictly required, as $^F is normally 2, but let's make sure...	1483	# not strictly required, as $^F is normally 2, but let's make sure...
1196	fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;	1484	fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
1197	fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;	1485	fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
		1486	}
		1487
		1488	$SIGPIPE_R
		1489	or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
		1490
		1491	$SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec;
1198	}	1492	}
1199		1493
1200	$SIGPIPE_R	1494	*signal = sub {
1201	or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";	1495	my (undef, %arg) = @_;
1202		1496
1203	$SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec);
1204	}
1205
1206	my $signal = uc $arg{signal}	1497	my $signal = uc $arg{signal}
1207	or Carp::croak "required option 'signal' is missing";	1498	or Carp::croak "required option 'signal' is missing";
1208		1499
		1500	if ($HAVE_ASYNC_INTERRUPT) {
		1501	# async::interrupt
		1502
		1503	$signal = sig2num $signal;
1209	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};	1504	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};
		1505
		1506	$SIG_ASY{$signal} ||= new Async::Interrupt
		1507	cb => sub { undef $SIG_EV{$signal} },
		1508	signal => $signal,
		1509	pipe => [$SIGPIPE_R->filenos],
		1510	pipe_autodrain => 0,
		1511	;
		1512
		1513	} else {
		1514	# pure perl
		1515
		1516	# AE::Util has been loaded in signal
		1517	$signal = sig2name $signal;
		1518	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};
		1519
1210	$SIG{$signal} ||= sub {	1520	$SIG{$signal} ||= sub {
1211	local $!;	1521	local $!;
1212	syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;	1522	syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
1213	undef $SIG_EV{$signal};	1523	undef $SIG_EV{$signal};
		1524	};
		1525
		1526	# can't do signal processing without introducing races in pure perl,
		1527	# so limit the signal latency.
		1528	_sig_add;
		1529	}
		1530
		1531	bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
		1532	};
		1533
		1534	*AnyEvent::Base::signal::DESTROY = sub {
		1535	my ($signal, $cb) = @{$_[0]};
		1536
		1537	_sig_del;
		1538
		1539	delete $SIG_CB{$signal}{$cb};
		1540
		1541	$HAVE_ASYNC_INTERRUPT
		1542	? delete $SIG_ASY{$signal}
		1543	: # delete doesn't work with older perls - they then
		1544	# print weird messages, or just unconditionally exit
		1545	# instead of getting the default action.
		1546	undef $SIG{$signal}
		1547	unless keys %{ $SIG_CB{$signal} };
		1548	};
1214	};	1549	};
1215		1550	die if $@;
1216	bless [$signal, $arg{cb}], "AnyEvent::Base::signal"	1551	&signal
1217	}
1218
1219	sub AnyEvent::Base::signal::DESTROY {
1220	my ($signal, $cb) = @{$_[0]};
1221
1222	delete $SIG_CB{$signal}{$cb};
1223
1224	# delete doesn't work with older perls - they then
1225	# print weird messages, or just unconditionally exit
1226	# instead of getting the default action.
1227	undef $SIG{$signal} unless keys %{ $SIG_CB{$signal} };
1228	}	1552	}
1229		1553
1230	# default implementation for ->child	1554	# default implementation for ->child
1231		1555
1232	our %PID_CB;	1556	our %PID_CB;
1233	our $CHLD_W;	1557	our $CHLD_W;
1234	our $CHLD_DELAY_W;	1558	our $CHLD_DELAY_W;
1235	our $WNOHANG;	1559	our $WNOHANG;
1236		1560
		1561	sub _emit_childstatus($$) {
		1562	my (undef, $rpid, $rstatus) = @_;
		1563
		1564	$_->($rpid, $rstatus)
		1565	for values %{ $PID_CB{$rpid} || {} },
		1566	values %{ $PID_CB{0} || {} };
		1567	}
		1568
1237	sub _sigchld {	1569	sub _sigchld {
		1570	my $pid;
		1571
		1572	AnyEvent->_emit_childstatus ($pid, $?)
1238	while (0 < (my $pid = waitpid -1, $WNOHANG)) {	1573	while ($pid = waitpid -1, $WNOHANG) > 0;
1239	$_->($pid, $?) for (values %{ $PID_CB{$pid} || {} }),
1240	(values %{ $PID_CB{0} || {} });
1241	}
1242	}	1574	}
1243		1575
1244	sub child {	1576	sub child {
1245	my (undef, %arg) = @_;	1577	my (undef, %arg) = @_;
1246		1578
1247	defined (my $pid = $arg{pid} + 0)	1579	defined (my $pid = $arg{pid} + 0)
1248	or Carp::croak "required option 'pid' is missing";	1580	or Carp::croak "required option 'pid' is missing";
1249		1581
1250	$PID_CB{$pid}{$arg{cb}} = $arg{cb};	1582	$PID_CB{$pid}{$arg{cb}} = $arg{cb};
1251		1583
		1584	# WNOHANG is almost cetrainly 1 everywhere
		1585	$WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/
		1586	? 1
1252	$WNOHANG ||= eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1;	1587	: eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1;
1253		1588
1254	unless ($CHLD_W) {	1589	unless ($CHLD_W) {
1255	$CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld);	1590	$CHLD_W = AE::signal CHLD => \&_sigchld;
1256	# child could be a zombie already, so make at least one round	1591	# child could be a zombie already, so make at least one round
1257	&_sigchld;	1592	&_sigchld;
1258	}	1593	}
1259		1594
1260	bless [$pid, $arg{cb}], "AnyEvent::Base::child"	1595	bless [$pid, $arg{cb}], "AnyEvent::Base::child"
…		…
1286	# never use more then 50% of the time for the idle watcher,	1621	# never use more then 50% of the time for the idle watcher,
1287	# within some limits	1622	# within some limits
1288	$w = 0.0001 if $w < 0.0001;	1623	$w = 0.0001 if $w < 0.0001;
1289	$w = 5 if $w > 5;	1624	$w = 5 if $w > 5;
1290		1625
1291	$w = AnyEvent->timer (after => $w, cb => $rcb);	1626	$w = AE::timer $w, 0, $rcb;
1292	} else {	1627	} else {
1293	# clean up...	1628	# clean up...
1294	undef $w;	1629	undef $w;
1295	undef $rcb;	1630	undef $rcb;
1296	}	1631	}
1297	};	1632	};
1298		1633
1299	$w = AnyEvent->timer (after => 0.05, cb => $rcb);	1634	$w = AE::timer 0.05, 0, $rcb;
1300		1635
1301	bless \\$cb, "AnyEvent::Base::idle"	1636	bless \\$cb, "AnyEvent::Base::idle"
1302	}	1637	}
1303		1638
1304	sub AnyEvent::Base::idle::DESTROY {	1639	sub AnyEvent::Base::idle::DESTROY {
…		…
1309		1644
1310	our @ISA = AnyEvent::CondVar::Base::;	1645	our @ISA = AnyEvent::CondVar::Base::;
1311		1646
1312	package AnyEvent::CondVar::Base;	1647	package AnyEvent::CondVar::Base;
1313		1648
1314	use overload	1649	#use overload
1315	'&{}' => sub { my $self = shift; sub { $self->send (@_) } },	1650	# '&{}' => sub { my $self = shift; sub { $self->send (@_) } },
1316	fallback => 1;	1651	# fallback => 1;
		1652
		1653	# save 300+ kilobytes by dirtily hardcoding overloading
		1654	${"AnyEvent::CondVar::Base::OVERLOAD"}{dummy}++; # Register with magic by touching.
		1655	*{'AnyEvent::CondVar::Base::()'} = sub { }; # "Make it findable via fetchmethod."
		1656	*{'AnyEvent::CondVar::Base::(&{}'} = sub { my $self = shift; sub { $self->send (@_) } }; # &{}
		1657	${'AnyEvent::CondVar::Base::()'} = 1; # fallback
		1658
		1659	our $WAITING;
1317		1660
1318	sub _send {	1661	sub _send {
1319	# nop	1662	# nop
1320	}	1663	}
1321		1664
…		…
1334	sub ready {	1677	sub ready {
1335	$_[0]{_ae_sent}	1678	$_[0]{_ae_sent}
1336	}	1679	}
1337		1680
1338	sub _wait {	1681	sub _wait {
		1682	$WAITING
		1683	and !$_[0]{_ae_sent}
		1684	and Carp::croak "AnyEvent::CondVar: recursive blocking wait detected";
		1685
		1686	local $WAITING = 1;
1339	AnyEvent->one_event while !$_[0]{_ae_sent};	1687	AnyEvent->one_event while !$_[0]{_ae_sent};
1340	}	1688	}
1341		1689
1342	sub recv {	1690	sub recv {
1343	$_[0]->_wait;	1691	$_[0]->_wait;
…		…
1345	Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak};	1693	Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak};
1346	wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0]	1694	wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0]
1347	}	1695	}
1348		1696
1349	sub cb {	1697	sub cb {
1350	$_[0]{_ae_cb} = $_[1] if @_ > 1;	1698	my $cv = shift;
		1699
		1700	@_
		1701	and $cv->{_ae_cb} = shift
		1702	and $cv->{_ae_sent}
		1703	and (delete $cv->{_ae_cb})->($cv);
		1704
1351	$_[0]{_ae_cb}	1705	$cv->{_ae_cb}
1352	}	1706	}
1353		1707
1354	sub begin {	1708	sub begin {
1355	++$_[0]{_ae_counter};	1709	++$_[0]{_ae_counter};
1356	$_[0]{_ae_end_cb} = $_[1] if @_ > 1;	1710	$_[0]{_ae_end_cb} = $_[1] if @_ > 1;
…		…
1405	C<PERL_ANYEVENT_MODEL>.	1759	C<PERL_ANYEVENT_MODEL>.
1406		1760
1407	When set to C<2> or higher, cause AnyEvent to report to STDERR which event	1761	When set to C<2> or higher, cause AnyEvent to report to STDERR which event
1408	model it chooses.	1762	model it chooses.
1409		1763
		1764	When set to C<8> or higher, then AnyEvent will report extra information on
		1765	which optional modules it loads and how it implements certain features.
		1766
1410	=item C<PERL_ANYEVENT_STRICT>	1767	=item C<PERL_ANYEVENT_STRICT>
1411		1768
1412	AnyEvent does not do much argument checking by default, as thorough	1769	AnyEvent does not do much argument checking by default, as thorough
1413	argument checking is very costly. Setting this variable to a true value	1770	argument checking is very costly. Setting this variable to a true value
1414	will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly	1771	will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly
1415	check the arguments passed to most method calls. If it finds any problems,	1772	check the arguments passed to most method calls. If it finds any problems,
1416	it will croak.	1773	it will croak.
1417		1774
1418	In other words, enables "strict" mode.	1775	In other words, enables "strict" mode.
1419		1776
1420	Unlike C<use strict>, it is definitely recommended to keep it off in	1777	Unlike C<use strict> (or it's modern cousin, C<< use L<common::sense>
1421	production. Keeping C<PERL_ANYEVENT_STRICT=1> in your environment while	1778	>>, it is definitely recommended to keep it off in production. Keeping
1422	developing programs can be very useful, however.	1779	C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs
		1780	can be very useful, however.
1423		1781
1424	=item C<PERL_ANYEVENT_MODEL>	1782	=item C<PERL_ANYEVENT_MODEL>
1425		1783
1426	This can be used to specify the event model to be used by AnyEvent, before	1784	This can be used to specify the event model to be used by AnyEvent, before
1427	auto detection and -probing kicks in. It must be a string consisting	1785	auto detection and -probing kicks in. It must be a string consisting
…		…
1470		1828
1471	=item C<PERL_ANYEVENT_MAX_FORKS>	1829	=item C<PERL_ANYEVENT_MAX_FORKS>
1472		1830
1473	The maximum number of child processes that C<AnyEvent::Util::fork_call>	1831	The maximum number of child processes that C<AnyEvent::Util::fork_call>
1474	will create in parallel.	1832	will create in parallel.
		1833
		1834	=item C<PERL_ANYEVENT_MAX_OUTSTANDING_DNS>
		1835
		1836	The default value for the C<max_outstanding> parameter for the default DNS
		1837	resolver - this is the maximum number of parallel DNS requests that are
		1838	sent to the DNS server.
		1839
		1840	=item C<PERL_ANYEVENT_RESOLV_CONF>
		1841
		1842	The file to use instead of F</etc/resolv.conf> (or OS-specific
		1843	configuration) in the default resolver. When set to the empty string, no
		1844	default config will be used.
		1845
		1846	=item C<PERL_ANYEVENT_CA_FILE>, C<PERL_ANYEVENT_CA_PATH>.
		1847
		1848	When neither C<ca_file> nor C<ca_path> was specified during
		1849	L<AnyEvent::TLS> context creation, and either of these environment
		1850	variables exist, they will be used to specify CA certificate locations
		1851	instead of a system-dependent default.
		1852
		1853	=item C<PERL_ANYEVENT_AVOID_GUARD> and C<PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT>
		1854
		1855	When these are set to C<1>, then the respective modules are not
		1856	loaded. Mostly good for testing AnyEvent itself.
1475		1857
1476	=back	1858	=back
1477		1859
1478	=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE	1860	=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE
1479		1861
…		…
1537	warn "read: $input\n"; # output what has been read	1919	warn "read: $input\n"; # output what has been read
1538	$cv->send if $input =~ /^q/i; # quit program if /^q/i	1920	$cv->send if $input =~ /^q/i; # quit program if /^q/i
1539	},	1921	},
1540	);	1922	);
1541		1923
1542	my $time_watcher; # can only be used once
1543
1544	sub new_timer {
1545	$timer = AnyEvent->timer (after => 1, cb => sub {	1924	my $time_watcher = AnyEvent->timer (after => 1, interval => 1, cb => sub {
1546	warn "timeout\n"; # print 'timeout' about every second	1925	warn "timeout\n"; # print 'timeout' at most every second
1547	&new_timer; # and restart the time
1548	});	1926	});
1549	}
1550
1551	new_timer; # create first timer
1552		1927
1553	$cv->recv; # wait until user enters /^q/i	1928	$cv->recv; # wait until user enters /^q/i
1554		1929
1555	=head1 REAL-WORLD EXAMPLE	1930	=head1 REAL-WORLD EXAMPLE
1556		1931
…		…
1687	through AnyEvent. The benchmark creates a lot of timers (with a zero	2062	through AnyEvent. The benchmark creates a lot of timers (with a zero
1688	timeout) and I/O watchers (watching STDOUT, a pty, to become writable,	2063	timeout) and I/O watchers (watching STDOUT, a pty, to become writable,
1689	which it is), lets them fire exactly once and destroys them again.	2064	which it is), lets them fire exactly once and destroys them again.
1690		2065
1691	Source code for this benchmark is found as F<eg/bench> in the AnyEvent	2066	Source code for this benchmark is found as F<eg/bench> in the AnyEvent
1692	distribution.	2067	distribution. It uses the L<AE> interface, which makes a real difference
		2068	for the EV and Perl backends only.
1693		2069
1694	=head3 Explanation of the columns	2070	=head3 Explanation of the columns
1695		2071
1696	I<watcher> is the number of event watchers created/destroyed. Since	2072	I<watcher> is the number of event watchers created/destroyed. Since
1697	different event models feature vastly different performances, each event	2073	different event models feature vastly different performances, each event
…		…
1718	watcher.	2094	watcher.
1719		2095
1720	=head3 Results	2096	=head3 Results
1721		2097
1722	name watchers bytes create invoke destroy comment	2098	name watchers bytes create invoke destroy comment
1723	EV/EV 400000 224 0.47 0.35 0.27 EV native interface	2099	EV/EV 100000 223 0.47 0.43 0.27 EV native interface
1724	EV/Any 100000 224 2.88 0.34 0.27 EV + AnyEvent watchers	2100	EV/Any 100000 223 0.48 0.42 0.26 EV + AnyEvent watchers
1725	CoroEV/Any 100000 224 2.85 0.35 0.28 coroutines + Coro::Signal	2101	Coro::EV/Any 100000 223 0.47 0.42 0.26 coroutines + Coro::Signal
1726	Perl/Any 100000 452 4.13 0.73 0.95 pure perl implementation	2102	Perl/Any 100000 431 2.70 0.74 0.92 pure perl implementation
1727	Event/Event 16000 517 32.20 31.80 0.81 Event native interface	2103	Event/Event 16000 516 31.16 31.84 0.82 Event native interface
1728	Event/Any 16000 590 35.85 31.55 1.06 Event + AnyEvent watchers	2104	Event/Any 16000 1203 42.61 34.79 1.80 Event + AnyEvent watchers
1729	IOAsync/Any 16000 989 38.10 32.77 11.13 via IO::Async::Loop::IO_Poll	2105	IOAsync/Any 16000 1911 41.92 27.45 16.81 via IO::Async::Loop::IO_Poll
1730	IOAsync/Any 16000 990 37.59 29.50 10.61 via IO::Async::Loop::Epoll	2106	IOAsync/Any 16000 1726 40.69 26.37 15.25 via IO::Async::Loop::Epoll
1731	Glib/Any 16000 1357 102.33 12.31 51.00 quadratic behaviour	2107	Glib/Any 16000 1118 89.00 12.57 51.17 quadratic behaviour
1732	Tk/Any 2000 1860 27.20 66.31 14.00 SEGV with >> 2000 watchers	2108	Tk/Any 2000 1346 20.96 10.75 8.00 SEGV with >> 2000 watchers
1733	POE/Event 2000 6328 109.99 751.67 14.02 via POE::Loop::Event	2109	POE/Any 2000 6951 108.97 795.32 14.24 via POE::Loop::Event
1734	POE/Select 2000 6027 94.54 809.13 579.80 via POE::Loop::Select	2110	POE/Any 2000 6648 94.79 774.40 575.51 via POE::Loop::Select
1735		2111
1736	=head3 Discussion	2112	=head3 Discussion
1737		2113
1738	The benchmark does I<not> measure scalability of the event loop very	2114	The benchmark does I<not> measure scalability of the event loop very
1739	well. For example, a select-based event loop (such as the pure perl one)	2115	well. For example, a select-based event loop (such as the pure perl one)
…		…
1751	benchmark machine, handling an event takes roughly 1600 CPU cycles with	2127	benchmark machine, handling an event takes roughly 1600 CPU cycles with
1752	EV, 3100 CPU cycles with AnyEvent's pure perl loop and almost 3000000 CPU	2128	EV, 3100 CPU cycles with AnyEvent's pure perl loop and almost 3000000 CPU
1753	cycles with POE.	2129	cycles with POE.
1754		2130
1755	C<EV> is the sole leader regarding speed and memory use, which are both	2131	C<EV> is the sole leader regarding speed and memory use, which are both
1756	maximal/minimal, respectively. Even when going through AnyEvent, it uses	2132	maximal/minimal, respectively. When using the L<AE> API there is zero
		2133	overhead (when going through the AnyEvent API create is about 5-6 times
		2134	slower, with other times being equal, so still uses far less memory than
1757	far less memory than any other event loop and is still faster than Event	2135	any other event loop and is still faster than Event natively).
1758	natively.
1759		2136
1760	The pure perl implementation is hit in a few sweet spots (both the	2137	The pure perl implementation is hit in a few sweet spots (both the
1761	constant timeout and the use of a single fd hit optimisations in the perl	2138	constant timeout and the use of a single fd hit optimisations in the perl
1762	interpreter and the backend itself). Nevertheless this shows that it	2139	interpreter and the backend itself). Nevertheless this shows that it
1763	adds very little overhead in itself. Like any select-based backend its	2140	adds very little overhead in itself. Like any select-based backend its
…		…
1837	In this benchmark, we use 10000 socket pairs (20000 sockets), of which 100	2214	In this benchmark, we use 10000 socket pairs (20000 sockets), of which 100
1838	(1%) are active. This mirrors the activity of large servers with many	2215	(1%) are active. This mirrors the activity of large servers with many
1839	connections, most of which are idle at any one point in time.	2216	connections, most of which are idle at any one point in time.
1840		2217
1841	Source code for this benchmark is found as F<eg/bench2> in the AnyEvent	2218	Source code for this benchmark is found as F<eg/bench2> in the AnyEvent
1842	distribution.	2219	distribution. It uses the L<AE> interface, which makes a real difference
		2220	for the EV and Perl backends only.
1843		2221
1844	=head3 Explanation of the columns	2222	=head3 Explanation of the columns
1845		2223
1846	I<sockets> is the number of sockets, and twice the number of "servers" (as	2224	I<sockets> is the number of sockets, and twice the number of "servers" (as
1847	each server has a read and write socket end).	2225	each server has a read and write socket end).
…		…
1855	a new one that moves the timeout into the future.	2233	a new one that moves the timeout into the future.
1856		2234
1857	=head3 Results	2235	=head3 Results
1858		2236
1859	name sockets create request	2237	name sockets create request
1860	EV 20000 69.01 11.16	2238	EV 20000 62.66 7.99
1861	Perl 20000 73.32 35.87	2239	Perl 20000 68.32 32.64
1862	IOAsync 20000 157.00 98.14 epoll	2240	IOAsync 20000 174.06 101.15 epoll
1863	IOAsync 20000 159.31 616.06 poll	2241	IOAsync 20000 174.67 610.84 poll
1864	Event 20000 212.62 257.32	2242	Event 20000 202.69 242.91
1865	Glib 20000 651.16 1896.30	2243	Glib 20000 557.01 1689.52
1866	POE 20000 349.67 12317.24 uses POE::Loop::Event	2244	POE 20000 341.54 12086.32 uses POE::Loop::Event
1867		2245
1868	=head3 Discussion	2246	=head3 Discussion
1869		2247
1870	This benchmark I<does> measure scalability and overall performance of the	2248	This benchmark I<does> measure scalability and overall performance of the
1871	particular event loop.	2249	particular event loop.
…		…
1997	As you can see, the AnyEvent + EV combination even beats the	2375	As you can see, the AnyEvent + EV combination even beats the
1998	hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl	2376	hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl
1999	backend easily beats IO::Lambda and POE.	2377	backend easily beats IO::Lambda and POE.
2000		2378
2001	And even the 100% non-blocking version written using the high-level (and	2379	And even the 100% non-blocking version written using the high-level (and
2002	slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda by a	2380	slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda
2003	large margin, even though it does all of DNS, tcp-connect and socket I/O	2381	higher level ("unoptimised") abstractions by a large margin, even though
2004	in a non-blocking way.	2382	it does all of DNS, tcp-connect and socket I/O in a non-blocking way.
2005		2383
2006	The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and	2384	The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and
2007	F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are	2385	F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are
2008	part of the IO::lambda distribution and were used without any changes.	2386	part of the IO::Lambda distribution and were used without any changes.
2009		2387
2010		2388
2011	=head1 SIGNALS	2389	=head1 SIGNALS
2012		2390
2013	AnyEvent currently installs handlers for these signals:	2391	AnyEvent currently installs handlers for these signals:
…		…
2018		2396
2019	A handler for C<SIGCHLD> is installed by AnyEvent's child watcher	2397	A handler for C<SIGCHLD> is installed by AnyEvent's child watcher
2020	emulation for event loops that do not support them natively. Also, some	2398	emulation for event loops that do not support them natively. Also, some
2021	event loops install a similar handler.	2399	event loops install a similar handler.
2022		2400
2023	If, when AnyEvent is loaded, SIGCHLD is set to IGNORE, then AnyEvent will	2401	Additionally, when AnyEvent is loaded and SIGCHLD is set to IGNORE, then
2024	reset it to default, to avoid losing child exit statuses.	2402	AnyEvent will reset it to default, to avoid losing child exit statuses.
2025		2403
2026	=item SIGPIPE	2404	=item SIGPIPE
2027		2405
2028	A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef>	2406	A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef>
2029	when AnyEvent gets loaded.	2407	when AnyEvent gets loaded.
…		…
2047	if $SIG{CHLD} eq 'IGNORE';	2425	if $SIG{CHLD} eq 'IGNORE';
2048		2426
2049	$SIG{PIPE} = sub { }	2427	$SIG{PIPE} = sub { }
2050	unless defined $SIG{PIPE};	2428	unless defined $SIG{PIPE};
2051		2429
		2430	=head1 RECOMMENDED/OPTIONAL MODULES
		2431
		2432	One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and
		2433	it's built-in modules) are required to use it.
		2434
		2435	That does not mean that AnyEvent won't take advantage of some additional
		2436	modules if they are installed.
		2437
		2438	This section epxlains which additional modules will be used, and how they
		2439	affect AnyEvent's operetion.
		2440
		2441	=over 4
		2442
		2443	=item L<Async::Interrupt>
		2444
		2445	This slightly arcane module is used to implement fast signal handling: To
		2446	my knowledge, there is no way to do completely race-free and quick
		2447	signal handling in pure perl. To ensure that signals still get
		2448	delivered, AnyEvent will start an interval timer to wake up perl (and
		2449	catch the signals) with some delay (default is 10 seconds, look for
		2450	C<$AnyEvent::MAX_SIGNAL_LATENCY>).
		2451
		2452	If this module is available, then it will be used to implement signal
		2453	catching, which means that signals will not be delayed, and the event loop
		2454	will not be interrupted regularly, which is more efficient (And good for
		2455	battery life on laptops).
		2456
		2457	This affects not just the pure-perl event loop, but also other event loops
		2458	that have no signal handling on their own (e.g. Glib, Tk, Qt).
		2459
		2460	Some event loops (POE, Event, Event::Lib) offer signal watchers natively,
		2461	and either employ their own workarounds (POE) or use AnyEvent's workaround
		2462	(using C<$AnyEvent::MAX_SIGNAL_LATENCY>). Installing L<Async::Interrupt>
		2463	does nothing for those backends.
		2464
		2465	=item L<EV>
		2466
		2467	This module isn't really "optional", as it is simply one of the backend
		2468	event loops that AnyEvent can use. However, it is simply the best event
		2469	loop available in terms of features, speed and stability: It supports
		2470	the AnyEvent API optimally, implements all the watcher types in XS, does
		2471	automatic timer adjustments even when no monotonic clock is available,
		2472	can take avdantage of advanced kernel interfaces such as C<epoll> and
		2473	C<kqueue>, and is the fastest backend I<by far>. You can even embed
		2474	L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>).
		2475
		2476	=item L<Guard>
		2477
		2478	The guard module, when used, will be used to implement
		2479	C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a
		2480	lot less memory), but otherwise doesn't affect guard operation much. It is
		2481	purely used for performance.
		2482
		2483	=item L<JSON> and L<JSON::XS>
		2484
		2485	One of these modules is required when you want to read or write JSON data
		2486	via L<AnyEvent::Handle>. It is also written in pure-perl, but can take
		2487	advantage of the ultra-high-speed L<JSON::XS> module when it is installed.
		2488
		2489	In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is
		2490	installed.
		2491
		2492	=item L<Net::SSLeay>
		2493
		2494	Implementing TLS/SSL in Perl is certainly interesting, but not very
		2495	worthwhile: If this module is installed, then L<AnyEvent::Handle> (with
		2496	the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL.
		2497
		2498	=item L<Time::HiRes>
		2499
		2500	This module is part of perl since release 5.008. It will be used when the
		2501	chosen event library does not come with a timing source on it's own. The
		2502	pure-perl event loop (L<AnyEvent::Impl::Perl>) will additionally use it to
		2503	try to use a monotonic clock for timing stability.
		2504
		2505	=back
		2506
		2507
2052	=head1 FORK	2508	=head1 FORK
2053		2509
2054	Most event libraries are not fork-safe. The ones who are usually are	2510	Most event libraries are not fork-safe. The ones who are usually are
2055	because they rely on inefficient but fork-safe C<select> or C<poll>	2511	because they rely on inefficient but fork-safe C<select> or C<poll>
2056	calls. Only L<EV> is fully fork-aware.	2512	calls. Only L<EV> is fully fork-aware.
2057		2513
2058	If you have to fork, you must either do so I<before> creating your first	2514	If you have to fork, you must either do so I<before> creating your first
2059	watcher OR you must not use AnyEvent at all in the child.	2515	watcher OR you must not use AnyEvent at all in the child OR you must do
		2516	something completely out of the scope of AnyEvent.
2060		2517
2061		2518
2062	=head1 SECURITY CONSIDERATIONS	2519	=head1 SECURITY CONSIDERATIONS
2063		2520
2064	AnyEvent can be forced to load any event model via	2521	AnyEvent can be forced to load any event model via
…		…
2102	L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.	2559	L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.
2103		2560
2104	Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,	2561	Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,
2105	L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,	2562	L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,
2106	L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,	2563	L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,
2107	L<AnyEvent::Impl::POE>.	2564	L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>.
2108		2565
2109	Non-blocking file handles, sockets, TCP clients and	2566	Non-blocking file handles, sockets, TCP clients and
2110	servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>.	2567	servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.
2111		2568
2112	Asynchronous DNS: L<AnyEvent::DNS>.	2569	Asynchronous DNS: L<AnyEvent::DNS>.
2113		2570
2114	Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>,	2571	Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>,
		2572	L<Coro::Event>,
2115		2573
2116	Nontrivial usage examples: L<Net::FCP>, L<Net::XMPP2>, L<AnyEvent::DNS>.	2574	Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::XMPP>,
		2575	L<AnyEvent::HTTP>.
2117		2576
2118		2577
2119	=head1 AUTHOR	2578	=head1 AUTHOR
2120		2579
2121	Marc Lehmann <schmorp@schmorp.de>	2580	Marc Lehmann <schmorp@schmorp.de>

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