[ViewVC] Diff of: cvs/AnyEvent/lib/AnyEvent.pm

Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.219 by root, Thu Jun 25 11:16:08 2009 UTC vs.
Revision 1.249 by root, Mon Jul 20 06:00:42 2009 UTC

…		…
1	=head1 NAME	1	=head1 NAME
2		2
3	AnyEvent - provide framework for multiple event loops	3	AnyEvent - events independent of event loop implementation
4		4
5	EV, Event, Glib, Tk, Perl, Event::Lib, Qt and POE are various supported	5	EV, Event, Glib, Tk, Perl, Event::Lib, Qt and POE are various supported
6	event loops.	6	event loops.
7		7
8	=head1 SYNOPSIS	8	=head1 SYNOPSIS
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	Respository>, 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?
…		…
176	=head2 I/O WATCHERS	184	=head2 I/O WATCHERS
177		185
178	You can create an I/O watcher by calling the C<< AnyEvent->io >> method	186	You can create an I/O watcher by calling the C<< AnyEvent->io >> method
179	with the following mandatory key-value pairs as arguments:	187	with the following mandatory key-value pairs as arguments:
180		188
181	C<fh> is the Perl I<file handle> (I<not> file descriptor) to watch	189	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	190	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	191	handle). Note that only file handles pointing to things for which
184	non-blocking operation makes sense are allowed. This includes sockets,	192	non-blocking operation makes sense are allowed. This includes sockets,
185	most character devices, pipes, fifos and so on, but not for example files	193	most character devices, pipes, fifos and so on, but not for example files
186	or block devices.	194	or block devices.
…		…
361	invocation, and callback invocation will be synchronous. Synchronous means	369	invocation, and callback invocation will be synchronous. Synchronous means
362	that it might take a while until the signal gets handled by the process,	370	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.	371	but it is guaranteed not to interrupt any other callbacks.
364		372
365	The main advantage of using these watchers is that you can share a signal	373	The main advantage of using these watchers is that you can share a signal
366	between multiple watchers.	374	between multiple watchers, and AnyEvent will ensure that signals will not
		375	interrupt your program at bad times.
367		376
368	This watcher might use C<%SIG>, so programs overwriting those signals	377	This watcher might use C<%SIG> (depending on the event loop used),
369	directly will likely not work correctly.	378	so programs overwriting those signals directly will likely not work
		379	correctly.
370		380
371	Example: exit on SIGINT	381	Example: exit on SIGINT
372		382
373	my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });	383	my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
		384
		385	=head3 Signal Races, Delays and Workarounds
		386
		387	Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching
		388	callbacks to signals in a generic way, which is a pity, as you cannot do
		389	race-free signal handling in perl. AnyEvent will try to do it's best, but
		390	in some cases, signals will be delayed. The maximum time a signal might
		391	be delayed is specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10
		392	seconds). This variable can be changed only before the first signal
		393	watcher is created, and should be left alone otherwise. Higher values
		394	will cause fewer spurious wake-ups, which is better for power and CPU
		395	saving. All these problems can be avoided by installing the optional
		396	L<Async::Interrupt> module. This will not work with inherently broken
		397	event loops such as L<Event> or L<Event::Lib> (and not with L<POE>
		398	currently, as POE does it's own workaround with one-second latency). With
		399	those, you just have to suffer the delays.
374		400
375	=head2 CHILD PROCESS WATCHERS	401	=head2 CHILD PROCESS WATCHERS
376		402
377	You can also watch on a child process exit and catch its exit status.	403	You can also watch on a child process exit and catch its exit status.
378		404
…		…
403		429
404	This means you cannot create a child watcher as the very first	430	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	431	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	432	watcher before you C<fork> the child (alternatively, you can call
407	C<AnyEvent::detect>).	433	C<AnyEvent::detect>).
		434
		435	As most event loops do not support waiting for child events, they will be
		436	emulated by AnyEvent in most cases, in which the latency and race problems
		437	mentioned in the description of signal watchers apply.
408		438
409	Example: fork a process and wait for it	439	Example: fork a process and wait for it
410		440
411	my $done = AnyEvent->condvar;	441	my $done = AnyEvent->condvar;
412		442
…		…
463		493
464	If you are familiar with some event loops you will know that all of them	494	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	495	require you to run some blocking "loop", "run" or similar function that
466	will actively watch for new events and call your callbacks.	496	will actively watch for new events and call your callbacks.
467		497
468	AnyEvent is different, it expects somebody else to run the event loop and	498	AnyEvent is slightly different: it expects somebody else to run the event
469	will only block when necessary (usually when told by the user).	499	loop and will only block when necessary (usually when told by the user).
470		500
471	The instrument to do that is called a "condition variable", so called	501	The instrument to do that is called a "condition variable", so called
472	because they represent a condition that must become true.	502	because they represent a condition that must become true.
473		503
		504	Now is probably a good time to look at the examples further below.
		505
474	Condition variables can be created by calling the C<< AnyEvent->condvar	506	Condition variables can be created by calling the C<< AnyEvent->condvar
475	>> method, usually without arguments. The only argument pair allowed is	507	>> 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	508	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	509	becomes true, with the condition variable as the first argument (but not
479	the results).	510	the results).
480		511
481	After creation, the condition variable is "false" until it becomes "true"	512	After creation, the condition variable is "false" until it becomes "true"
…		…
530	after => 1,	561	after => 1,
531	cb => sub { $result_ready->send },	562	cb => sub { $result_ready->send },
532	);	563	);
533		564
534	# this "blocks" (while handling events) till the callback	565	# this "blocks" (while handling events) till the callback
535	# calls send	566	# calls -<send
536	$result_ready->recv;	567	$result_ready->recv;
537		568
538	Example: wait for a timer, but take advantage of the fact that	569	Example: wait for a timer, but take advantage of the fact that condition
539	condition variables are also code references.	570	variables are also callable directly.
540		571
541	my $done = AnyEvent->condvar;	572	my $done = AnyEvent->condvar;
542	my $delay = AnyEvent->timer (after => 5, cb => $done);	573	my $delay = AnyEvent->timer (after => 5, cb => $done);
543	$done->recv;	574	$done->recv;
544		575
…		…
550		581
551	...	582	...
552		583
553	my @info = $couchdb->info->recv;	584	my @info = $couchdb->info->recv;
554		585
555	And this is how you would just ste a callback to be called whenever the	586	And this is how you would just set a callback to be called whenever the
556	results are available:	587	results are available:
557		588
558	$couchdb->info->cb (sub {	589	$couchdb->info->cb (sub {
559	my @info = $_[0]->recv;	590	my @info = $_[0]->recv;
560	});	591	});
…		…
578	immediately from within send.	609	immediately from within send.
579		610
580	Any arguments passed to the C<send> call will be returned by all	611	Any arguments passed to the C<send> call will be returned by all
581	future C<< ->recv >> calls.	612	future C<< ->recv >> calls.
582		613
583	Condition variables are overloaded so one can call them directly	614	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	615	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	616	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		617
592	=item $cv->croak ($error)	618	=item $cv->croak ($error)
593		619
594	Similar to send, but causes all call's to C<< ->recv >> to invoke	620	Similar to send, but causes all call's to C<< ->recv >> to invoke
595	C<Carp::croak> with the given error message/object/scalar.	621	C<Carp::croak> with the given error message/object/scalar.
596		622
597	This can be used to signal any errors to the condition variable	623	This can be used to signal any errors to the condition variable
598	user/consumer.	624	user/consumer. Doing it this way instead of calling C<croak> directly
		625	delays the error detetcion, but has the overwhelmign advantage that it
		626	diagnoses the error at the place where the result is expected, and not
		627	deep in some event clalback without connection to the actual code causing
		628	the problem.
599		629
600	=item $cv->begin ([group callback])	630	=item $cv->begin ([group callback])
601		631
602	=item $cv->end	632	=item $cv->end
603
604	These two methods are EXPERIMENTAL and MIGHT CHANGE.
605		633
606	These two methods can be used to combine many transactions/events into	634	These two methods can be used to combine many transactions/events into
607	one. For example, a function that pings many hosts in parallel might want	635	one. For example, a function that pings many hosts in parallel might want
608	to use a condition variable for the whole process.	636	to use a condition variable for the whole process.
609		637
…		…
611	C<< ->end >> will decrement it. If the counter reaches C<0> in C<< ->end	639	C<< ->end >> will decrement it. If the counter reaches C<0> in C<< ->end
612	>>, the (last) callback passed to C<begin> will be executed. That callback	640	>>, the (last) callback passed to C<begin> will be executed. That callback
613	is I<supposed> to call C<< ->send >>, but that is not required. If no	641	is I<supposed> to call C<< ->send >>, but that is not required. If no
614	callback was set, C<send> will be called without any arguments.	642	callback was set, C<send> will be called without any arguments.
615		643
616	Let's clarify this with the ping example:	644	You can think of C<< $cv->send >> giving you an OR condition (one call
		645	sends), while C<< $cv->begin >> and C<< $cv->end >> giving you an AND
		646	condition (all C<begin> calls must be C<end>'ed before the condvar sends).
		647
		648	Let's start with a simple example: you have two I/O watchers (for example,
		649	STDOUT and STDERR for a program), and you want to wait for both streams to
		650	close before activating a condvar:
		651
		652	my $cv = AnyEvent->condvar;
		653
		654	$cv->begin; # first watcher
		655	my $w1 = AnyEvent->io (fh => $fh1, cb => sub {
		656	defined sysread $fh1, my $buf, 4096
		657	or $cv->end;
		658	});
		659
		660	$cv->begin; # second watcher
		661	my $w2 = AnyEvent->io (fh => $fh2, cb => sub {
		662	defined sysread $fh2, my $buf, 4096
		663	or $cv->end;
		664	});
		665
		666	$cv->recv;
		667
		668	This works because for every event source (EOF on file handle), there is
		669	one call to C<begin>, so the condvar waits for all calls to C<end> before
		670	sending.
		671
		672	The ping example mentioned above is slightly more complicated, as the
		673	there are results to be passwd back, and the number of tasks that are
		674	begung can potentially be zero:
617		675
618	my $cv = AnyEvent->condvar;	676	my $cv = AnyEvent->condvar;
619		677
620	my %result;	678	my %result;
621	$cv->begin (sub { $cv->send (\%result) });	679	$cv->begin (sub { $cv->send (\%result) });
…		…
641	loop, which serves two important purposes: first, it sets the callback	699	loop, which serves two important purposes: first, it sets the callback
642	to be called once the counter reaches C<0>, and second, it ensures that	700	to be called once the counter reaches C<0>, and second, it ensures that
643	C<send> is called even when C<no> hosts are being pinged (the loop	701	C<send> is called even when C<no> hosts are being pinged (the loop
644	doesn't execute once).	702	doesn't execute once).
645		703
646	This is the general pattern when you "fan out" into multiple subrequests:	704	This is the general pattern when you "fan out" into multiple (but
647	use an outer C<begin>/C<end> pair to set the callback and ensure C<end>	705	potentially none) subrequests: use an outer C<begin>/C<end> pair to set
648	is called at least once, and then, for each subrequest you start, call	706	the callback and ensure C<end> is called at least once, and then, for each
649	C<begin> and for each subrequest you finish, call C<end>.	707	subrequest you start, call C<begin> and for each subrequest you finish,
		708	call C<end>.
650		709
651	=back	710	=back
652		711
653	=head3 METHODS FOR CONSUMERS	712	=head3 METHODS FOR CONSUMERS
654		713
…		…
670	function will call C<croak>.	729	function will call C<croak>.
671		730
672	In list context, all parameters passed to C<send> will be returned,	731	In list context, all parameters passed to C<send> will be returned,
673	in scalar context only the first one will be returned.	732	in scalar context only the first one will be returned.
674		733
		734	Note that doing a blocking wait in a callback is not supported by any
		735	event loop, that is, recursive invocation of a blocking C<< ->recv
		736	>> is not allowed, and the C<recv> call will C<croak> if such a
		737	condition is detected. This condition can be slightly loosened by using
		738	L<Coro::AnyEvent>, which allows you to do a blocking C<< ->recv >> from
		739	any thread that doesn't run the event loop itself.
		740
675	Not all event models support a blocking wait - some die in that case	741	Not all event models support a blocking wait - some die in that case
676	(programs might want to do that to stay interactive), so I<if you are	742	(programs might want to do that to stay interactive), so I<if you are
677	using this from a module, never require a blocking wait>, but let the	743	using this from a module, never require a blocking wait>. Instead, let the
678	caller decide whether the call will block or not (for example, by coupling	744	caller decide whether the call will block or not (for example, by coupling
679	condition variables with some kind of request results and supporting	745	condition variables with some kind of request results and supporting
680	callbacks so the caller knows that getting the result will not block,	746	callbacks so the caller knows that getting the result will not block,
681	while still supporting blocking waits if the caller so desires).	747	while still supporting blocking waits if the caller so desires).
682		748
683	Another reason I<never> to C<< ->recv >> in a module is that you cannot
684	sensibly have two C<< ->recv >>'s in parallel, as that would require
685	multiple interpreters or coroutines/threads, none of which C<AnyEvent>
686	can supply.
687
688	The L<Coro> module, however, I<can> and I<does> supply coroutines and, in
689	fact, L<Coro::AnyEvent> replaces AnyEvent's condvars by coroutine-safe
690	versions and also integrates coroutines into AnyEvent, making blocking
691	C<< ->recv >> calls perfectly safe as long as they are done from another
692	coroutine (one that doesn't run the event loop).
693
694	You can ensure that C<< -recv >> never blocks by setting a callback and	749	You can ensure that C<< -recv >> never blocks by setting a callback and
695	only calling C<< ->recv >> from within that callback (or at a later	750	only calling C<< ->recv >> from within that callback (or at a later
696	time). This will work even when the event loop does not support blocking	751	time). This will work even when the event loop does not support blocking
697	waits otherwise.	752	waits otherwise.
698		753
…		…
711	variable itself. Calling C<recv> inside the callback or at any later time	766	variable itself. Calling C<recv> inside the callback or at any later time
712	is guaranteed not to block.	767	is guaranteed not to block.
713		768
714	=back	769	=back
715		770
		771	=head1 SUPPORTED EVENT LOOPS/BACKENDS
		772
		773	The available backend classes are (every class has its own manpage):
		774
		775	=over 4
		776
		777	=item Backends that are autoprobed when no other event loop can be found.
		778
		779	EV is the preferred backend when no other event loop seems to be in
		780	use. If EV is not installed, then AnyEvent will try Event, and, failing
		781	that, will fall back to its own pure-perl implementation, which is
		782	available everywhere as it comes with AnyEvent itself.
		783
		784	AnyEvent::Impl::EV based on EV (interface to libev, best choice).
		785	AnyEvent::Impl::Event based on Event, very stable, few glitches.
		786	AnyEvent::Impl::Perl pure-perl implementation, fast and portable.
		787
		788	=item Backends that are transparently being picked up when they are used.
		789
		790	These will be used when they are currently loaded when the first watcher
		791	is created, in which case it is assumed that the application is using
		792	them. This means that AnyEvent will automatically pick the right backend
		793	when the main program loads an event module before anything starts to
		794	create watchers. Nothing special needs to be done by the main program.
		795
		796	AnyEvent::Impl::Glib based on Glib, slow but very stable.
		797	AnyEvent::Impl::Tk based on Tk, very broken.
		798	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
		799	AnyEvent::Impl::POE based on POE, very slow, some limitations.
		800
		801	=item Backends with special needs.
		802
		803	Qt requires the Qt::Application to be instantiated first, but will
		804	otherwise be picked up automatically. As long as the main program
		805	instantiates the application before any AnyEvent watchers are created,
		806	everything should just work.
		807
		808	AnyEvent::Impl::Qt based on Qt.
		809
		810	Support for IO::Async can only be partial, as it is too broken and
		811	architecturally limited to even support the AnyEvent API. It also
		812	is the only event loop that needs the loop to be set explicitly, so
		813	it can only be used by a main program knowing about AnyEvent. See
		814	L<AnyEvent::Impl::Async> for the gory details.
		815
		816	AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed.
		817
		818	=item Event loops that are indirectly supported via other backends.
		819
		820	Some event loops can be supported via other modules:
		821
		822	There is no direct support for WxWidgets (L<Wx>) or L<Prima>.
		823
		824	B<WxWidgets> has no support for watching file handles. However, you can
		825	use WxWidgets through the POE adaptor, as POE has a Wx backend that simply
		826	polls 20 times per second, which was considered to be too horrible to even
		827	consider for AnyEvent.
		828
		829	B<Prima> is not supported as nobody seems to be using it, but it has a POE
		830	backend, so it can be supported through POE.
		831
		832	AnyEvent knows about both L<Prima> and L<Wx>, however, and will try to
		833	load L<POE> when detecting them, in the hope that POE will pick them up,
		834	in which case everything will be automatic.
		835
		836	=back
		837
716	=head1 GLOBAL VARIABLES AND FUNCTIONS	838	=head1 GLOBAL VARIABLES AND FUNCTIONS
717		839
		840	These are not normally required to use AnyEvent, but can be useful to
		841	write AnyEvent extension modules.
		842
718	=over 4	843	=over 4
719		844
720	=item $AnyEvent::MODEL	845	=item $AnyEvent::MODEL
721		846
722	Contains C<undef> until the first watcher is being created. Then it	847	Contains C<undef> until the first watcher is being created, before the
		848	backend has been autodetected.
		849
723	contains the event model that is being used, which is the name of the	850	Afterwards it contains the event model that is being used, which is the
724	Perl class implementing the model. This class is usually one of the	851	name of the Perl class implementing the model. This class is usually one
725	C<AnyEvent::Impl:xxx> modules, but can be any other class in the case	852	of the C<AnyEvent::Impl:xxx> modules, but can be any other class in the
726	AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode>).	853	case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it
727		854	will be C<urxvt::anyevent>).
728	The known classes so far are:
729
730	AnyEvent::Impl::EV based on EV (an interface to libev, best choice).
731	AnyEvent::Impl::Event based on Event, second best choice.
732	AnyEvent::Impl::Perl pure-perl implementation, fast and portable.
733	AnyEvent::Impl::Glib based on Glib, third-best choice.
734	AnyEvent::Impl::Tk based on Tk, very bad choice.
735	AnyEvent::Impl::Qt based on Qt, cannot be autoprobed (see its docs).
736	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
737	AnyEvent::Impl::POE based on POE, not generic enough for full support.
738
739	# warning, support for IO::Async is only partial, as it is too broken
740	# and limited toe ven support the AnyEvent API. See AnyEvent::Impl::Async.
741	AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed (see its docs).
742
743	There is no support for WxWidgets, as WxWidgets has no support for
744	watching file handles. However, you can use WxWidgets through the
745	POE Adaptor, as POE has a Wx backend that simply polls 20 times per
746	second, which was considered to be too horrible to even consider for
747	AnyEvent. Likewise, other POE backends can be used by AnyEvent by using
748	it's adaptor.
749
750	AnyEvent knows about L<Prima> and L<Wx> and will try to use L<POE> when
751	autodetecting them.
752		855
753	=item AnyEvent::detect	856	=item AnyEvent::detect
754		857
755	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model	858	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model
756	if necessary. You should only call this function right before you would	859	if necessary. You should only call this function right before you would
757	have created an AnyEvent watcher anyway, that is, as late as possible at	860	have created an AnyEvent watcher anyway, that is, as late as possible at
758	runtime.	861	runtime, and not e.g. while initialising of your module.
		862
		863	If you need to do some initialisation before AnyEvent watchers are
		864	created, use C<post_detect>.
759		865
760	=item $guard = AnyEvent::post_detect { BLOCK }	866	=item $guard = AnyEvent::post_detect { BLOCK }
761		867
762	Arranges for the code block to be executed as soon as the event model is	868	Arranges for the code block to be executed as soon as the event model is
763	autodetected (or immediately if this has already happened).	869	autodetected (or immediately if this has already happened).
		870
		871	The block will be executed I<after> the actual backend has been detected
		872	(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been
		873	created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do
		874	other initialisations - see the sources of L<AnyEvent::Strict> or
		875	L<AnyEvent::AIO> to see how this is used.
		876
		877	The most common usage is to create some global watchers, without forcing
		878	event module detection too early, for example, L<AnyEvent::AIO> creates
		879	and installs the global L<IO::AIO> watcher in a C<post_detect> block to
		880	avoid autodetecting the event module at load time.
764		881
765	If called in scalar or list context, then it creates and returns an object	882	If called in scalar or list context, then it creates and returns an object
766	that automatically removes the callback again when it is destroyed. See	883	that automatically removes the callback again when it is destroyed. See
767	L<Coro::BDB> for a case where this is useful.	884	L<Coro::BDB> for a case where this is useful.
768		885
…		…
771	If there are any code references in this array (you can C<push> to it	888	If there are any code references in this array (you can C<push> to it
772	before or after loading AnyEvent), then they will called directly after	889	before or after loading AnyEvent), then they will called directly after
773	the event loop has been chosen.	890	the event loop has been chosen.
774		891
775	You should check C<$AnyEvent::MODEL> before adding to this array, though:	892	You should check C<$AnyEvent::MODEL> before adding to this array, though:
776	if it contains a true value then the event loop has already been detected,	893	if it is defined then the event loop has already been detected, and the
777	and the array will be ignored.	894	array will be ignored.
778		895
779	Best use C<AnyEvent::post_detect { BLOCK }> instead.	896	Best use C<AnyEvent::post_detect { BLOCK }> when your application allows
		897	it,as it takes care of these details.
		898
		899	This variable is mainly useful for modules that can do something useful
		900	when AnyEvent is used and thus want to know when it is initialised, but do
		901	not need to even load it by default. This array provides the means to hook
		902	into AnyEvent passively, without loading it.
780		903
781	=back	904	=back
782		905
783	=head1 WHAT TO DO IN A MODULE	906	=head1 WHAT TO DO IN A MODULE
784		907
…		…
839		962
840		963
841	=head1 OTHER MODULES	964	=head1 OTHER MODULES
842		965
843	The following is a non-exhaustive list of additional modules that use	966	The following is a non-exhaustive list of additional modules that use
844	AnyEvent and can therefore be mixed easily with other AnyEvent modules	967	AnyEvent as a client and can therefore be mixed easily with other AnyEvent
845	in the same program. Some of the modules come with AnyEvent, some are	968	modules and other event loops in the same program. Some of the modules
846	available via CPAN.	969	come with AnyEvent, most are available via CPAN.
847		970
848	=over 4	971	=over 4
849		972
850	=item L<AnyEvent::Util>	973	=item L<AnyEvent::Util>
851		974
…		…
860		983
861	=item L<AnyEvent::Handle>	984	=item L<AnyEvent::Handle>
862		985
863	Provide read and write buffers, manages watchers for reads and writes,	986	Provide read and write buffers, manages watchers for reads and writes,
864	supports raw and formatted I/O, I/O queued and fully transparent and	987	supports raw and formatted I/O, I/O queued and fully transparent and
865	non-blocking SSL/TLS.	988	non-blocking SSL/TLS (via L<AnyEvent::TLS>.
866		989
867	=item L<AnyEvent::DNS>	990	=item L<AnyEvent::DNS>
868		991
869	Provides rich asynchronous DNS resolver capabilities.	992	Provides rich asynchronous DNS resolver capabilities.
870		993
…		…
898		1021
899	=item L<AnyEvent::GPSD>	1022	=item L<AnyEvent::GPSD>
900		1023
901	A non-blocking interface to gpsd, a daemon delivering GPS information.	1024	A non-blocking interface to gpsd, a daemon delivering GPS information.
902		1025
		1026	=item L<AnyEvent::IRC>
		1027
		1028	AnyEvent based IRC client module family (replacing the older Net::IRC3).
		1029
		1030	=item L<AnyEvent::XMPP>
		1031
		1032	AnyEvent based XMPP (Jabber protocol) module family (replacing the older
		1033	Net::XMPP2>.
		1034
903	=item L<AnyEvent::IGS>	1035	=item L<AnyEvent::IGS>
904		1036
905	A non-blocking interface to the Internet Go Server protocol (used by	1037	A non-blocking interface to the Internet Go Server protocol (used by
906	L<App::IGS>).	1038	L<App::IGS>).
907		1039
908	=item L<AnyEvent::IRC>
909
910	AnyEvent based IRC client module family (replacing the older Net::IRC3).
911
912	=item L<Net::XMPP2>
913
914	AnyEvent based XMPP (Jabber protocol) module family.
915
916	=item L<Net::FCP>	1040	=item L<Net::FCP>
917		1041
918	AnyEvent-based implementation of the Freenet Client Protocol, birthplace	1042	AnyEvent-based implementation of the Freenet Client Protocol, birthplace
919	of AnyEvent.	1043	of AnyEvent.
920		1044
…		…
924		1048
925	=item L<Coro>	1049	=item L<Coro>
926		1050
927	Has special support for AnyEvent via L<Coro::AnyEvent>.	1051	Has special support for AnyEvent via L<Coro::AnyEvent>.
928		1052
929	=item L<IO::Lambda>
930
931	The lambda approach to I/O - don't ask, look there. Can use AnyEvent.
932
933	=back	1053	=back
934		1054
935	=cut	1055	=cut
936		1056
937	package AnyEvent;	1057	package AnyEvent;
938		1058
		1059	# basically a tuned-down version of common::sense
		1060	sub common_sense {
939	no warnings;	1061	# no warnings
		1062	${^WARNING_BITS} ^= ${^WARNING_BITS};
940	use strict qw(vars subs);	1063	# use strict vars subs
		1064	$^H \|= 0x00000600;
		1065	}
941		1066
		1067	BEGIN { AnyEvent::common_sense }
		1068
942	use Carp;	1069	use Carp ();
943		1070
944	our $VERSION = 4.412;	1071	our $VERSION = 4.85;
945	our $MODEL;	1072	our $MODEL;
946		1073
947	our $AUTOLOAD;	1074	our $AUTOLOAD;
948	our @ISA;	1075	our @ISA;
949		1076
950	our @REGISTRY;	1077	our @REGISTRY;
951		1078
952	our $WIN32;	1079	our $WIN32;
		1080
		1081	our $VERBOSE;
953		1082
954	BEGIN {	1083	BEGIN {
955	eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }";	1084	eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }";
956	eval "sub TAINT(){ " . (${^TAINT}*1) . " }";	1085	eval "sub TAINT(){ " . (${^TAINT}*1) . " }";
957		1086
958	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}	1087	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}
959	if ${^TAINT};	1088	if ${^TAINT};
960	}
961		1089
962	our $verbose = $ENV{PERL_ANYEVENT_VERBOSE}*1;	1090	$VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1;
		1091
		1092	}
		1093
		1094	our $MAX_SIGNAL_LATENCY = 10;
963		1095
964	our %PROTOCOL; # (ipv4\|ipv6) => (1\|2), higher numbers are preferred	1096	our %PROTOCOL; # (ipv4\|ipv6) => (1\|2), higher numbers are preferred
965		1097
966	{	1098	{
967	my $idx;	1099	my $idx;
…		…
975	[Event:: => AnyEvent::Impl::Event::],	1107	[Event:: => AnyEvent::Impl::Event::],
976	[AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::],	1108	[AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::],
977	# everything below here will not be autoprobed	1109	# everything below here will not be autoprobed
978	# as the pureperl backend should work everywhere	1110	# as the pureperl backend should work everywhere
979	# and is usually faster	1111	# and is usually faster
980	[Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
981	[Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers	1112	[Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers
982	[Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy	1113	[Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
		1114	[Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
983	[Qt:: => AnyEvent::Impl::Qt::], # requires special main program	1115	[Qt:: => AnyEvent::Impl::Qt::], # requires special main program
984	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza	1116	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
985	[Wx:: => AnyEvent::Impl::POE::],	1117	[Wx:: => AnyEvent::Impl::POE::],
986	[Prima:: => AnyEvent::Impl::POE::],	1118	[Prima:: => AnyEvent::Impl::POE::],
987	# IO::Async is just too broken - we would need workaorunds for its	1119	# IO::Async is just too broken - we would need workarounds for its
988	# byzantine signal and broken child handling, among others.	1120	# byzantine signal and broken child handling, among others.
989	# IO::Async is rather hard to detect, as it doesn't have any	1121	# IO::Async is rather hard to detect, as it doesn't have any
990	# obvious default class.	1122	# obvious default class.
991	# [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program	1123	# [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program
992	# [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program	1124	# [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program
…		…
1018	@post_detect = grep $_ != ${$_[0]}, @post_detect;	1150	@post_detect = grep $_ != ${$_[0]}, @post_detect;
1019	}	1151	}
1020		1152
1021	sub detect() {	1153	sub detect() {
1022	unless ($MODEL) {	1154	unless ($MODEL) {
1023	no strict 'refs';
1024	local $SIG{__DIE__};	1155	local $SIG{__DIE__};
1025		1156
1026	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {	1157	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {
1027	my $model = "AnyEvent::Impl::$1";	1158	my $model = "AnyEvent::Impl::$1";
1028	if (eval "require $model") {	1159	if (eval "require $model") {
1029	$MODEL = $model;	1160	$MODEL = $model;
1030	warn "AnyEvent: loaded model '$model' (forced by \$PERL_ANYEVENT_MODEL), using it.\n" if $verbose > 1;	1161	warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2;
1031	} else {	1162	} else {
1032	warn "AnyEvent: unable to load model '$model' (from \$PERL_ANYEVENT_MODEL):\n$@" if $verbose;	1163	warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE;
1033	}	1164	}
1034	}	1165	}
1035		1166
1036	# check for already loaded models	1167	# check for already loaded models
1037	unless ($MODEL) {	1168	unless ($MODEL) {
1038	for (@REGISTRY, @models) {	1169	for (@REGISTRY, @models) {
1039	my ($package, $model) = @$_;	1170	my ($package, $model) = @$_;
1040	if (${"$package\::VERSION"} > 0) {	1171	if (${"$package\::VERSION"} > 0) {
1041	if (eval "require $model") {	1172	if (eval "require $model") {
1042	$MODEL = $model;	1173	$MODEL = $model;
1043	warn "AnyEvent: autodetected model '$model', using it.\n" if $verbose > 1;	1174	warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2;
1044	last;	1175	last;
1045	}	1176	}
1046	}	1177	}
1047	}	1178	}
1048		1179
…		…
1053	my ($package, $model) = @$_;	1184	my ($package, $model) = @$_;
1054	if (eval "require $package"	1185	if (eval "require $package"
1055	and ${"$package\::VERSION"} > 0	1186	and ${"$package\::VERSION"} > 0
1056	and eval "require $model") {	1187	and eval "require $model") {
1057	$MODEL = $model;	1188	$MODEL = $model;
1058	warn "AnyEvent: autoprobed model '$model', using it.\n" if $verbose > 1;	1189	warn "AnyEvent: autoprobed model '$model', using it.\n" if $VERBOSE >= 2;
1059	last;	1190	last;
1060	}	1191	}
1061	}	1192	}
1062		1193
1063	$MODEL	1194	$MODEL
…		…
1079		1210
1080	sub AUTOLOAD {	1211	sub AUTOLOAD {
1081	(my $func = $AUTOLOAD) =~ s/.*://;	1212	(my $func = $AUTOLOAD) =~ s/.*://;
1082		1213
1083	$method{$func}	1214	$method{$func}
1084	or croak "$func: not a valid method for AnyEvent objects";	1215	or Carp::croak "$func: not a valid method for AnyEvent objects";
1085		1216
1086	detect unless $MODEL;	1217	detect unless $MODEL;
1087		1218
1088	my $class = shift;	1219	my $class = shift;
1089	$class->$func (@_);	1220	$class->$func (@_);
…		…
1094	# allow only one watcher per fd, so we dup it to get a different one).	1225	# allow only one watcher per fd, so we dup it to get a different one).
1095	sub _dupfh($$;$$) {	1226	sub _dupfh($$;$$) {
1096	my ($poll, $fh, $r, $w) = @_;	1227	my ($poll, $fh, $r, $w) = @_;
1097		1228
1098	# cygwin requires the fh mode to be matching, unix doesn't	1229	# cygwin requires the fh mode to be matching, unix doesn't
1099	my ($rw, $mode) = $poll eq "r" ? ($r, "<")	1230	my ($rw, $mode) = $poll eq "r" ? ($r, "<&") : ($w, ">&");
1100	: $poll eq "w" ? ($w, ">")
1101	: Carp::croak "AnyEvent->io requires poll set to either 'r' or 'w'";
1102		1231
1103	open my $fh2, "$mode&" . fileno $fh	1232	open my $fh2, $mode, $fh
1104	or die "cannot dup() filehandle: $!,";	1233	or die "AnyEvent->io: cannot dup() filehandle in mode '$poll': $!,";
1105		1234
1106	# we assume CLOEXEC is already set by perl in all important cases	1235	# we assume CLOEXEC is already set by perl in all important cases
1107		1236
1108	($fh2, $rw)	1237	($fh2, $rw)
1109	}	1238	}
1110		1239
1111	package AnyEvent::Base;	1240	package AnyEvent::Base;
1112		1241
1113	# default implementations for many methods	1242	# default implementations for many methods
1114		1243
1115	BEGIN {	1244	sub _time {
		1245	# probe for availability of Time::HiRes
1116	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {	1246	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
		1247	warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8;
1117	*_time = \&Time::HiRes::time;	1248	*_time = \&Time::HiRes::time;
1118	# if (eval "use POSIX (); (POSIX::times())...	1249	# if (eval "use POSIX (); (POSIX::times())...
1119	} else {	1250	} else {
		1251	warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE;
1120	*_time = sub { time }; # epic fail	1252	*_time = sub { time }; # epic fail
1121	}	1253	}
		1254
		1255	&_time
1122	}	1256	}
1123		1257
1124	sub time { _time }	1258	sub time { _time }
1125	sub now { _time }	1259	sub now { _time }
1126	sub now_update { }	1260	sub now_update { }
…		…
1131	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"	1265	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"
1132	}	1266	}
1133		1267
1134	# default implementation for ->signal	1268	# default implementation for ->signal
1135		1269
		1270	our $HAVE_ASYNC_INTERRUPT;
1136	our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);	1271	our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);
		1272	our (%SIG_ASY, %SIG_ASY_W);
		1273	our ($SIG_COUNT, $SIG_TW);
1137		1274
1138	sub _signal_exec {	1275	sub _signal_exec {
		1276	$HAVE_ASYNC_INTERRUPT
		1277	? $SIGPIPE_R->drain
1139	sysread $SIGPIPE_R, my $dummy, 4;	1278	: sysread $SIGPIPE_R, my $dummy, 9;
1140		1279
1141	while (%SIG_EV) {	1280	while (%SIG_EV) {
1142	for (keys %SIG_EV) {	1281	for (keys %SIG_EV) {
1143	delete $SIG_EV{$_};	1282	delete $SIG_EV{$_};
1144	$_->() for values %{ $SIG_CB{$_} \|\| {} };	1283	$_->() for values %{ $SIG_CB{$_} \|\| {} };
1145	}	1284	}
1146	}	1285	}
1147	}	1286	}
1148		1287
		1288	# install a dumym wakeupw atcher to reduce signal catching latency
		1289	sub _sig_add() {
		1290	unless ($SIG_COUNT++) {
		1291	# try to align timer on a full-second boundary, if possible
		1292	my $NOW = AnyEvent->now;
		1293
		1294	$SIG_TW = AnyEvent->timer (
		1295	after => $MAX_SIGNAL_LATENCY - ($NOW - int $NOW),
		1296	interval => $MAX_SIGNAL_LATENCY,
		1297	cb => sub { }, # just for the PERL_ASYNC_CHECK
		1298	);
		1299	}
		1300	}
		1301
		1302	sub _sig_del {
		1303	undef $SIG_TW
		1304	unless --$SIG_COUNT;
		1305	}
		1306
		1307	sub _signal {
		1308	my (undef, %arg) = @_;
		1309
		1310	my $signal = uc $arg{signal}
		1311	or Carp::croak "required option 'signal' is missing";
		1312
		1313	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};
		1314
		1315	if ($HAVE_ASYNC_INTERRUPT) {
		1316	# async::interrupt
		1317
		1318	$SIG_ASY{$signal} \|\|= do {
		1319	my $asy = new Async::Interrupt
		1320	cb => sub { undef $SIG_EV{$signal} },
		1321	signal => $signal,
		1322	pipe => [$SIGPIPE_R->filenos],
		1323	;
		1324	$asy->pipe_autodrain (0);
		1325
		1326	$asy
		1327	};
		1328
		1329	} else {
		1330	# pure perl
		1331
		1332	$SIG{$signal} \|\|= sub {
		1333	local $!;
		1334	syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
		1335	undef $SIG_EV{$signal};
		1336	};
		1337
		1338	# can't do signal processing without introducing races in pure perl,
		1339	# so limit the signal latency.
		1340	_sig_add;
		1341	}
		1342
		1343	bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
		1344	}
		1345
1149	sub signal {	1346	sub signal {
1150	my (undef, %arg) = @_;	1347	# probe for availability of Async::Interrupt
		1348	if (!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT} && eval "use Async::Interrupt 0.6 (); 1") {
		1349	warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8;
1151		1350
1152	unless ($SIGPIPE_R) {	1351	$HAVE_ASYNC_INTERRUPT = 1;
		1352	$SIGPIPE_R = new Async::Interrupt::EventPipe;
		1353	$SIG_IO = AnyEvent->io (fh => $SIGPIPE_R->fileno, poll => "r", cb => \&_signal_exec);
		1354
		1355	} else {
		1356	warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;
		1357
1153	require Fcntl;	1358	require Fcntl;
1154		1359
1155	if (AnyEvent::WIN32) {	1360	if (AnyEvent::WIN32) {
1156	require AnyEvent::Util;	1361	require AnyEvent::Util;
1157		1362
…		…
1172	or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";	1377	or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1173		1378
1174	$SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec);	1379	$SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec);
1175	}	1380	}
1176		1381
1177	my $signal = uc $arg{signal}	1382	*signal = \&_signal;
1178	or Carp::croak "required option 'signal' is missing";	1383	&signal
1179
1180	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1181	$SIG{$signal} \|\|= sub {
1182	local $!;
1183	syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
1184	undef $SIG_EV{$signal};
1185	};
1186
1187	bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1188	}	1384	}
1189		1385
1190	sub AnyEvent::Base::signal::DESTROY {	1386	sub AnyEvent::Base::signal::DESTROY {
1191	my ($signal, $cb) = @{$_[0]};	1387	my ($signal, $cb) = @{$_[0]};
1192		1388
		1389	_sig_del;
		1390
1193	delete $SIG_CB{$signal}{$cb};	1391	delete $SIG_CB{$signal}{$cb};
1194		1392
		1393	$HAVE_ASYNC_INTERRUPT
		1394	? delete $SIG_ASY{$signal}
1195	# delete doesn't work with older perls - they then	1395	: # delete doesn't work with older perls - they then
1196	# print weird messages, or just unconditionally exit	1396	# print weird messages, or just unconditionally exit
1197	# instead of getting the default action.	1397	# instead of getting the default action.
		1398	undef $SIG{$signal}
1198	undef $SIG{$signal} unless keys %{ $SIG_CB{$signal} };	1399	unless keys %{ $SIG_CB{$signal} };
1199	}	1400	}
1200		1401
1201	# default implementation for ->child	1402	# default implementation for ->child
1202		1403
1203	our %PID_CB;	1404	our %PID_CB;
…		…
1205	our $CHLD_DELAY_W;	1406	our $CHLD_DELAY_W;
1206	our $WNOHANG;	1407	our $WNOHANG;
1207		1408
1208	sub _sigchld {	1409	sub _sigchld {
1209	while (0 < (my $pid = waitpid -1, $WNOHANG)) {	1410	while (0 < (my $pid = waitpid -1, $WNOHANG)) {
		1411	$_->($pid, $?)
1210	$_->($pid, $?) for (values %{ $PID_CB{$pid} \|\| {} }),	1412	for values %{ $PID_CB{$pid} \|\| {} },
1211	(values %{ $PID_CB{0} \|\| {} });	1413	values %{ $PID_CB{0} \|\| {} };
1212	}	1414	}
1213	}	1415	}
1214		1416
1215	sub child {	1417	sub child {
1216	my (undef, %arg) = @_;	1418	my (undef, %arg) = @_;
…		…
1218	defined (my $pid = $arg{pid} + 0)	1420	defined (my $pid = $arg{pid} + 0)
1219	or Carp::croak "required option 'pid' is missing";	1421	or Carp::croak "required option 'pid' is missing";
1220		1422
1221	$PID_CB{$pid}{$arg{cb}} = $arg{cb};	1423	$PID_CB{$pid}{$arg{cb}} = $arg{cb};
1222		1424
		1425	# WNOHANG is almost cetrainly 1 everywhere
		1426	$WNOHANG \|\|= $^O =~ /^(?:openbsd\|netbsd\|linux\|freebsd\|cygwin\|MSWin32)$/
		1427	? 1
1223	$WNOHANG \|\|= eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } \|\| 1;	1428	: eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } \|\| 1;
1224		1429
1225	unless ($CHLD_W) {	1430	unless ($CHLD_W) {
1226	$CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld);	1431	$CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld);
1227	# child could be a zombie already, so make at least one round	1432	# child could be a zombie already, so make at least one round
1228	&_sigchld;	1433	&_sigchld;
…		…
1280		1485
1281	our @ISA = AnyEvent::CondVar::Base::;	1486	our @ISA = AnyEvent::CondVar::Base::;
1282		1487
1283	package AnyEvent::CondVar::Base;	1488	package AnyEvent::CondVar::Base;
1284		1489
1285	use overload	1490	#use overload
1286	'&{}' => sub { my $self = shift; sub { $self->send (@_) } },	1491	# '&{}' => sub { my $self = shift; sub { $self->send (@_) } },
1287	fallback => 1;	1492	# fallback => 1;
		1493
		1494	# save 300+ kilobytes by dirtily hardcoding overloading
		1495	${"AnyEvent::CondVar::Base::OVERLOAD"}{dummy}++; # Register with magic by touching.
		1496	*{'AnyEvent::CondVar::Base::()'} = sub { }; # "Make it findable via fetchmethod."
		1497	*{'AnyEvent::CondVar::Base::(&{}'} = sub { my $self = shift; sub { $self->send (@_) } }; # &{}
		1498	${'AnyEvent::CondVar::Base::()'} = 1; # fallback
		1499
		1500	our $WAITING;
1288		1501
1289	sub _send {	1502	sub _send {
1290	# nop	1503	# nop
1291	}	1504	}
1292		1505
…		…
1305	sub ready {	1518	sub ready {
1306	$_[0]{_ae_sent}	1519	$_[0]{_ae_sent}
1307	}	1520	}
1308		1521
1309	sub _wait {	1522	sub _wait {
		1523	$WAITING
		1524	and !$_[0]{_ae_sent}
		1525	and Carp::croak "AnyEvent::CondVar: recursive blocking wait detected";
		1526
		1527	local $WAITING = 1;
1310	AnyEvent->one_event while !$_[0]{_ae_sent};	1528	AnyEvent->one_event while !$_[0]{_ae_sent};
1311	}	1529	}
1312		1530
1313	sub recv {	1531	sub recv {
1314	$_[0]->_wait;	1532	$_[0]->_wait;
…		…
1376	C<PERL_ANYEVENT_MODEL>.	1594	C<PERL_ANYEVENT_MODEL>.
1377		1595
1378	When set to C<2> or higher, cause AnyEvent to report to STDERR which event	1596	When set to C<2> or higher, cause AnyEvent to report to STDERR which event
1379	model it chooses.	1597	model it chooses.
1380		1598
		1599	When set to C<8> or higher, then AnyEvent will report extra information on
		1600	which optional modules it loads and how it implements certain features.
		1601
1381	=item C<PERL_ANYEVENT_STRICT>	1602	=item C<PERL_ANYEVENT_STRICT>
1382		1603
1383	AnyEvent does not do much argument checking by default, as thorough	1604	AnyEvent does not do much argument checking by default, as thorough
1384	argument checking is very costly. Setting this variable to a true value	1605	argument checking is very costly. Setting this variable to a true value
1385	will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly	1606	will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly
1386	check the arguments passed to most method calls. If it finds any problems,	1607	check the arguments passed to most method calls. If it finds any problems,
1387	it will croak.	1608	it will croak.
1388		1609
1389	In other words, enables "strict" mode.	1610	In other words, enables "strict" mode.
1390		1611
1391	Unlike C<use strict>, it is definitely recommended to keep it off in	1612	Unlike C<use strict> (or it's modern cousin, C<< use L<common::sense>
1392	production. Keeping C<PERL_ANYEVENT_STRICT=1> in your environment while	1613	>>, it is definitely recommended to keep it off in production. Keeping
1393	developing programs can be very useful, however.	1614	C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs
		1615	can be very useful, however.
1394		1616
1395	=item C<PERL_ANYEVENT_MODEL>	1617	=item C<PERL_ANYEVENT_MODEL>
1396		1618
1397	This can be used to specify the event model to be used by AnyEvent, before	1619	This can be used to specify the event model to be used by AnyEvent, before
1398	auto detection and -probing kicks in. It must be a string consisting	1620	auto detection and -probing kicks in. It must be a string consisting
…		…
1441		1663
1442	=item C<PERL_ANYEVENT_MAX_FORKS>	1664	=item C<PERL_ANYEVENT_MAX_FORKS>
1443		1665
1444	The maximum number of child processes that C<AnyEvent::Util::fork_call>	1666	The maximum number of child processes that C<AnyEvent::Util::fork_call>
1445	will create in parallel.	1667	will create in parallel.
		1668
		1669	=item C<PERL_ANYEVENT_MAX_OUTSTANDING_DNS>
		1670
		1671	The default value for the C<max_outstanding> parameter for the default DNS
		1672	resolver - this is the maximum number of parallel DNS requests that are
		1673	sent to the DNS server.
		1674
		1675	=item C<PERL_ANYEVENT_RESOLV_CONF>
		1676
		1677	The file to use instead of F</etc/resolv.conf> (or OS-specific
		1678	configuration) in the default resolver. When set to the empty string, no
		1679	default config will be used.
		1680
		1681	=item C<PERL_ANYEVENT_CA_FILE>, C<PERL_ANYEVENT_CA_PATH>.
		1682
		1683	When neither C<ca_file> nor C<ca_path> was specified during
		1684	L<AnyEvent::TLS> context creation, and either of these environment
		1685	variables exist, they will be used to specify CA certificate locations
		1686	instead of a system-dependent default.
		1687
		1688	=item C<PERL_ANYEVENT_AVOID_GUARD> and C<PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT>
		1689
		1690	When these are set to C<1>, then the respective modules are not
		1691	loaded. Mostly good for testing AnyEvent itself.
1446		1692
1447	=back	1693	=back
1448		1694
1449	=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE	1695	=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE
1450		1696
…		…
1695	EV/Any 100000 224 2.88 0.34 0.27 EV + AnyEvent watchers	1941	EV/Any 100000 224 2.88 0.34 0.27 EV + AnyEvent watchers
1696	CoroEV/Any 100000 224 2.85 0.35 0.28 coroutines + Coro::Signal	1942	CoroEV/Any 100000 224 2.85 0.35 0.28 coroutines + Coro::Signal
1697	Perl/Any 100000 452 4.13 0.73 0.95 pure perl implementation	1943	Perl/Any 100000 452 4.13 0.73 0.95 pure perl implementation
1698	Event/Event 16000 517 32.20 31.80 0.81 Event native interface	1944	Event/Event 16000 517 32.20 31.80 0.81 Event native interface
1699	Event/Any 16000 590 35.85 31.55 1.06 Event + AnyEvent watchers	1945	Event/Any 16000 590 35.85 31.55 1.06 Event + AnyEvent watchers
		1946	IOAsync/Any 16000 989 38.10 32.77 11.13 via IO::Async::Loop::IO_Poll
		1947	IOAsync/Any 16000 990 37.59 29.50 10.61 via IO::Async::Loop::Epoll
1700	Glib/Any 16000 1357 102.33 12.31 51.00 quadratic behaviour	1948	Glib/Any 16000 1357 102.33 12.31 51.00 quadratic behaviour
1701	Tk/Any 2000 1860 27.20 66.31 14.00 SEGV with >> 2000 watchers	1949	Tk/Any 2000 1860 27.20 66.31 14.00 SEGV with >> 2000 watchers
1702	POE/Event 2000 6328 109.99 751.67 14.02 via POE::Loop::Event	1950	POE/Event 2000 6328 109.99 751.67 14.02 via POE::Loop::Event
1703	POE/Select 2000 6027 94.54 809.13 579.80 via POE::Loop::Select	1951	POE/Select 2000 6027 94.54 809.13 579.80 via POE::Loop::Select
1704		1952
…		…
1733	performance becomes really bad with lots of file descriptors (and few of	1981	performance becomes really bad with lots of file descriptors (and few of
1734	them active), of course, but this was not subject of this benchmark.	1982	them active), of course, but this was not subject of this benchmark.
1735		1983
1736	The C<Event> module has a relatively high setup and callback invocation	1984	The C<Event> module has a relatively high setup and callback invocation
1737	cost, but overall scores in on the third place.	1985	cost, but overall scores in on the third place.
		1986
		1987	C<IO::Async> performs admirably well, about on par with C<Event>, even
		1988	when using its pure perl backend.
1738		1989
1739	C<Glib>'s memory usage is quite a bit higher, but it features a	1990	C<Glib>'s memory usage is quite a bit higher, but it features a
1740	faster callback invocation and overall ends up in the same class as	1991	faster callback invocation and overall ends up in the same class as
1741	C<Event>. However, Glib scales extremely badly, doubling the number of	1992	C<Event>. However, Glib scales extremely badly, doubling the number of
1742	watchers increases the processing time by more than a factor of four,	1993	watchers increases the processing time by more than a factor of four,
…		…
1820	it to another server. This includes deleting the old timeout and creating	2071	it to another server. This includes deleting the old timeout and creating
1821	a new one that moves the timeout into the future.	2072	a new one that moves the timeout into the future.
1822		2073
1823	=head3 Results	2074	=head3 Results
1824		2075
1825	name sockets create request	2076	name sockets create request
1826	EV 20000 69.01 11.16	2077	EV 20000 69.01 11.16
1827	Perl 20000 73.32 35.87	2078	Perl 20000 73.32 35.87
		2079	IOAsync 20000 157.00 98.14 epoll
		2080	IOAsync 20000 159.31 616.06 poll
1828	Event 20000 212.62 257.32	2081	Event 20000 212.62 257.32
1829	Glib 20000 651.16 1896.30	2082	Glib 20000 651.16 1896.30
1830	POE 20000 349.67 12317.24 uses POE::Loop::Event	2083	POE 20000 349.67 12317.24 uses POE::Loop::Event
1831		2084
1832	=head3 Discussion	2085	=head3 Discussion
1833		2086
1834	This benchmark I<does> measure scalability and overall performance of the	2087	This benchmark I<does> measure scalability and overall performance of the
1835	particular event loop.	2088	particular event loop.
…		…
1837	EV is again fastest. Since it is using epoll on my system, the setup time	2090	EV is again fastest. Since it is using epoll on my system, the setup time
1838	is relatively high, though.	2091	is relatively high, though.
1839		2092
1840	Perl surprisingly comes second. It is much faster than the C-based event	2093	Perl surprisingly comes second. It is much faster than the C-based event
1841	loops Event and Glib.	2094	loops Event and Glib.
		2095
		2096	IO::Async performs very well when using its epoll backend, and still quite
		2097	good compared to Glib when using its pure perl backend.
1842		2098
1843	Event suffers from high setup time as well (look at its code and you will	2099	Event suffers from high setup time as well (look at its code and you will
1844	understand why). Callback invocation also has a high overhead compared to	2100	understand why). Callback invocation also has a high overhead compared to
1845	the C<< $_->() for .. >>-style loop that the Perl event loop uses. Event	2101	the C<< $_->() for .. >>-style loop that the Perl event loop uses. Event
1846	uses select or poll in basically all documented configurations.	2102	uses select or poll in basically all documented configurations.
…		…
1979		2235
1980	A handler for C<SIGCHLD> is installed by AnyEvent's child watcher	2236	A handler for C<SIGCHLD> is installed by AnyEvent's child watcher
1981	emulation for event loops that do not support them natively. Also, some	2237	emulation for event loops that do not support them natively. Also, some
1982	event loops install a similar handler.	2238	event loops install a similar handler.
1983		2239
1984	If, when AnyEvent is loaded, SIGCHLD is set to IGNORE, then AnyEvent will	2240	Additionally, when AnyEvent is loaded and SIGCHLD is set to IGNORE, then
1985	reset it to default, to avoid losing child exit statuses.	2241	AnyEvent will reset it to default, to avoid losing child exit statuses.
1986		2242
1987	=item SIGPIPE	2243	=item SIGPIPE
1988		2244
1989	A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef>	2245	A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef>
1990	when AnyEvent gets loaded.	2246	when AnyEvent gets loaded.
…		…
2008	if $SIG{CHLD} eq 'IGNORE';	2264	if $SIG{CHLD} eq 'IGNORE';
2009		2265
2010	$SIG{PIPE} = sub { }	2266	$SIG{PIPE} = sub { }
2011	unless defined $SIG{PIPE};	2267	unless defined $SIG{PIPE};
2012		2268
		2269	=head1 RECOMMENDED/OPTIONAL MODULES
		2270
		2271	One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and
		2272	it's built-in modules) are required to use it.
		2273
		2274	That does not mean that AnyEvent won't take advantage of some additional
		2275	modules if they are installed.
		2276
		2277	This section epxlains which additional modules will be used, and how they
		2278	affect AnyEvent's operetion.
		2279
		2280	=over 4
		2281
		2282	=item L<Async::Interrupt>
		2283
		2284	This slightly arcane module is used to implement fast signal handling: To
		2285	my knowledge, there is no way to do completely race-free and quick
		2286	signal handling in pure perl. To ensure that signals still get
		2287	delivered, AnyEvent will start an interval timer to wake up perl (and
		2288	catch the signals) with some delay (default is 10 seconds, look for
		2289	C<$AnyEvent::MAX_SIGNAL_LATENCY>).
		2290
		2291	If this module is available, then it will be used to implement signal
		2292	catching, which means that signals will not be delayed, and the event loop
		2293	will not be interrupted regularly, which is more efficient (And good for
		2294	battery life on laptops).
		2295
		2296	This affects not just the pure-perl event loop, but also other event loops
		2297	that have no signal handling on their own (e.g. Glib, Tk, Qt).
		2298
		2299	Some event loops (POE, Event, Event::Lib) offer signal watchers natively,
		2300	and either employ their own workarounds (POE) or use AnyEvent's workaround
		2301	(using C<$AnyEvent::MAX_SIGNAL_LATENCY>). Installing L<Async::Interrupt>
		2302	does nothing for those backends.
		2303
		2304	=item L<EV>
		2305
		2306	This module isn't really "optional", as it is simply one of the backend
		2307	event loops that AnyEvent can use. However, it is simply the best event
		2308	loop available in terms of features, speed and stability: It supports
		2309	the AnyEvent API optimally, implements all the watcher types in XS, does
		2310	automatic timer adjustments even when no monotonic clock is available,
		2311	can take avdantage of advanced kernel interfaces such as C<epoll> and
		2312	C<kqueue>, and is the fastest backend I<by far>. You can even embed
		2313	L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>).
		2314
		2315	=item L<Guard>
		2316
		2317	The guard module, when used, will be used to implement
		2318	C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a
		2319	lot less memory), but otherwise doesn't affect guard operation much. It is
		2320	purely used for performance.
		2321
		2322	=item L<JSON> and L<JSON::XS>
		2323
		2324	This module is required when you want to read or write JSON data via
		2325	L<AnyEvent::Handle>. It is also written in pure-perl, but can take
		2326	advantage of the ultra-high-speed L<JSON::XS> module when it is installed.
		2327
		2328	In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is
		2329	installed.
		2330
		2331	=item L<Net::SSLeay>
		2332
		2333	Implementing TLS/SSL in Perl is certainly interesting, but not very
		2334	worthwhile: If this module is installed, then L<AnyEvent::Handle> (with
		2335	the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL.
		2336
		2337	=item L<Time::HiRes>
		2338
		2339	This module is part of perl since release 5.008. It will be used when the
		2340	chosen event library does not come with a timing source on it's own. The
		2341	pure-perl event loop (L<AnyEvent::Impl::Perl>) will additionally use it to
		2342	try to use a monotonic clock for timing stability.
		2343
		2344	=back
		2345
		2346
2013	=head1 FORK	2347	=head1 FORK
2014		2348
2015	Most event libraries are not fork-safe. The ones who are usually are	2349	Most event libraries are not fork-safe. The ones who are usually are
2016	because they rely on inefficient but fork-safe C<select> or C<poll>	2350	because they rely on inefficient but fork-safe C<select> or C<poll>
2017	calls. Only L<EV> is fully fork-aware.	2351	calls. Only L<EV> is fully fork-aware.
2018		2352
2019	If you have to fork, you must either do so I<before> creating your first	2353	If you have to fork, you must either do so I<before> creating your first
2020	watcher OR you must not use AnyEvent at all in the child.	2354	watcher OR you must not use AnyEvent at all in the child OR you must do
		2355	something completely out of the scope of AnyEvent.
2021		2356
2022		2357
2023	=head1 SECURITY CONSIDERATIONS	2358	=head1 SECURITY CONSIDERATIONS
2024		2359
2025	AnyEvent can be forced to load any event model via	2360	AnyEvent can be forced to load any event model via
…		…
2063	L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.	2398	L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.
2064		2399
2065	Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,	2400	Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,
2066	L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,	2401	L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,
2067	L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,	2402	L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,
2068	L<AnyEvent::Impl::POE>.	2403	L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>.
2069		2404
2070	Non-blocking file handles, sockets, TCP clients and	2405	Non-blocking file handles, sockets, TCP clients and
2071	servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>.	2406	servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.
2072		2407
2073	Asynchronous DNS: L<AnyEvent::DNS>.	2408	Asynchronous DNS: L<AnyEvent::DNS>.
2074		2409
2075	Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>,	2410	Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>,
		2411	L<Coro::Event>,
2076		2412
2077	Nontrivial usage examples: L<Net::FCP>, L<Net::XMPP2>, L<AnyEvent::DNS>.	2413	Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::XMPP>,
		2414	L<AnyEvent::HTTP>.
2078		2415
2079		2416
2080	=head1 AUTHOR	2417	=head1 AUTHOR
2081		2418
2082	Marc Lehmann <schmorp@schmorp.de>	2419	Marc Lehmann <schmorp@schmorp.de>

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Comparing AnyEvent/lib/AnyEvent.pm (file contents): Revision 1.219 by root, Thu Jun 25 11:16:08 2009 UTC vs. Revision 1.249 by root, Mon Jul 20 06:00:42 2009 UTC

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Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.219 by root, Thu Jun 25 11:16:08 2009 UTC vs.
Revision 1.249 by root, Mon Jul 20 06:00:42 2009 UTC