[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 1.243 by root, Fri Jul 17 23:12:20 2009 UTC

…		…
176	=head2 I/O WATCHERS	176	=head2 I/O WATCHERS
177		177
178	You can create an I/O watcher by calling the C<< AnyEvent->io >> method	178	You can create an I/O watcher by calling the C<< AnyEvent->io >> method
179	with the following mandatory key-value pairs as arguments:	179	with the following mandatory key-value pairs as arguments:
180		180
181	C<fh> is the Perl I<file handle> (I<not> file descriptor) to watch	181	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	182	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	183	handle). Note that only file handles pointing to things for which
184	non-blocking operation makes sense are allowed. This includes sockets,	184	non-blocking operation makes sense are allowed. This includes sockets,
185	most character devices, pipes, fifos and so on, but not for example files	185	most character devices, pipes, fifos and so on, but not for example files
186	or block devices.	186	or block devices.
…		…
361	invocation, and callback invocation will be synchronous. Synchronous means	361	invocation, and callback invocation will be synchronous. Synchronous means
362	that it might take a while until the signal gets handled by the process,	362	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.	363	but it is guaranteed not to interrupt any other callbacks.
364		364
365	The main advantage of using these watchers is that you can share a signal	365	The main advantage of using these watchers is that you can share a signal
366	between multiple watchers.	366	between multiple watchers, and AnyEvent will ensure that signals will not
		367	interrupt your program at bad times.
367		368
368	This watcher might use C<%SIG>, so programs overwriting those signals	369	This watcher might use C<%SIG> (depending on the event loop used),
369	directly will likely not work correctly.	370	so programs overwriting those signals directly will likely not work
		371	correctly.
		372
		373	Also note that many event loops (e.g. Glib, Tk, Qt, IO::Async) do not
		374	support attaching callbacks to signals, which is a pity, as you cannot do
		375	race-free signal handling in perl. AnyEvent will try to do it's best, but
		376	in some cases, signals will be delayed. The maximum time a signal might
		377	be delayed is specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10
		378	seconds). This variable can be changed only before the first signal
		379	watcher is created, and should be left alone otherwise. Higher values
		380	will cause fewer spurious wake-ups, which is better for power and CPU
		381	saving. All these problems can be avoided by installing the optional
		382	L<Async::Interrupt> module.
370		383
371	Example: exit on SIGINT	384	Example: exit on SIGINT
372		385
373	my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });	386	my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
374		387
…		…
403		416
404	This means you cannot create a child watcher as the very first	417	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	418	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	419	watcher before you C<fork> the child (alternatively, you can call
407	C<AnyEvent::detect>).	420	C<AnyEvent::detect>).
		421
		422	As most event loops do not support waiting for child events, they will be
		423	emulated by AnyEvent in most cases, in which the latency and race problems
		424	mentioned in the description of signal watchers apply.
408		425
409	Example: fork a process and wait for it	426	Example: fork a process and wait for it
410		427
411	my $done = AnyEvent->condvar;	428	my $done = AnyEvent->condvar;
412		429
…		…
463		480
464	If you are familiar with some event loops you will know that all of them	481	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	482	require you to run some blocking "loop", "run" or similar function that
466	will actively watch for new events and call your callbacks.	483	will actively watch for new events and call your callbacks.
467		484
468	AnyEvent is different, it expects somebody else to run the event loop and	485	AnyEvent is slightly different: it expects somebody else to run the event
469	will only block when necessary (usually when told by the user).	486	loop and will only block when necessary (usually when told by the user).
470		487
471	The instrument to do that is called a "condition variable", so called	488	The instrument to do that is called a "condition variable", so called
472	because they represent a condition that must become true.	489	because they represent a condition that must become true.
473		490
		491	Now is probably a good time to look at the examples further below.
		492
474	Condition variables can be created by calling the C<< AnyEvent->condvar	493	Condition variables can be created by calling the C<< AnyEvent->condvar
475	>> method, usually without arguments. The only argument pair allowed is	494	>> 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	495	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	496	becomes true, with the condition variable as the first argument (but not
479	the results).	497	the results).
480		498
481	After creation, the condition variable is "false" until it becomes "true"	499	After creation, the condition variable is "false" until it becomes "true"
…		…
530	after => 1,	548	after => 1,
531	cb => sub { $result_ready->send },	549	cb => sub { $result_ready->send },
532	);	550	);
533		551
534	# this "blocks" (while handling events) till the callback	552	# this "blocks" (while handling events) till the callback
535	# calls send	553	# calls -<send
536	$result_ready->recv;	554	$result_ready->recv;
537		555
538	Example: wait for a timer, but take advantage of the fact that	556	Example: wait for a timer, but take advantage of the fact that condition
539	condition variables are also code references.	557	variables are also callable directly.
540		558
541	my $done = AnyEvent->condvar;	559	my $done = AnyEvent->condvar;
542	my $delay = AnyEvent->timer (after => 5, cb => $done);	560	my $delay = AnyEvent->timer (after => 5, cb => $done);
543	$done->recv;	561	$done->recv;
544		562
…		…
550		568
551	...	569	...
552		570
553	my @info = $couchdb->info->recv;	571	my @info = $couchdb->info->recv;
554		572
555	And this is how you would just ste a callback to be called whenever the	573	And this is how you would just set a callback to be called whenever the
556	results are available:	574	results are available:
557		575
558	$couchdb->info->cb (sub {	576	$couchdb->info->cb (sub {
559	my @info = $_[0]->recv;	577	my @info = $_[0]->recv;
560	});	578	});
…		…
578	immediately from within send.	596	immediately from within send.
579		597
580	Any arguments passed to the C<send> call will be returned by all	598	Any arguments passed to the C<send> call will be returned by all
581	future C<< ->recv >> calls.	599	future C<< ->recv >> calls.
582		600
583	Condition variables are overloaded so one can call them directly	601	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	602	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	603	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		604
592	=item $cv->croak ($error)	605	=item $cv->croak ($error)
593		606
594	Similar to send, but causes all call's to C<< ->recv >> to invoke	607	Similar to send, but causes all call's to C<< ->recv >> to invoke
595	C<Carp::croak> with the given error message/object/scalar.	608	C<Carp::croak> with the given error message/object/scalar.
596		609
597	This can be used to signal any errors to the condition variable	610	This can be used to signal any errors to the condition variable
598	user/consumer.	611	user/consumer. Doing it this way instead of calling C<croak> directly
		612	delays the error detetcion, but has the overwhelmign advantage that it
		613	diagnoses the error at the place where the result is expected, and not
		614	deep in some event clalback without connection to the actual code causing
		615	the problem.
599		616
600	=item $cv->begin ([group callback])	617	=item $cv->begin ([group callback])
601		618
602	=item $cv->end	619	=item $cv->end
603
604	These two methods are EXPERIMENTAL and MIGHT CHANGE.
605		620
606	These two methods can be used to combine many transactions/events into	621	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	622	one. For example, a function that pings many hosts in parallel might want
608	to use a condition variable for the whole process.	623	to use a condition variable for the whole process.
609		624
…		…
611	C<< ->end >> will decrement it. If the counter reaches C<0> in C<< ->end	626	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	627	>>, 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	628	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.	629	callback was set, C<send> will be called without any arguments.
615		630
616	Let's clarify this with the ping example:	631	You can think of C<< $cv->send >> giving you an OR condition (one call
		632	sends), while C<< $cv->begin >> and C<< $cv->end >> giving you an AND
		633	condition (all C<begin> calls must be C<end>'ed before the condvar sends).
		634
		635	Let's start with a simple example: you have two I/O watchers (for example,
		636	STDOUT and STDERR for a program), and you want to wait for both streams to
		637	close before activating a condvar:
		638
		639	my $cv = AnyEvent->condvar;
		640
		641	$cv->begin; # first watcher
		642	my $w1 = AnyEvent->io (fh => $fh1, cb => sub {
		643	defined sysread $fh1, my $buf, 4096
		644	or $cv->end;
		645	});
		646
		647	$cv->begin; # second watcher
		648	my $w2 = AnyEvent->io (fh => $fh2, cb => sub {
		649	defined sysread $fh2, my $buf, 4096
		650	or $cv->end;
		651	});
		652
		653	$cv->recv;
		654
		655	This works because for every event source (EOF on file handle), there is
		656	one call to C<begin>, so the condvar waits for all calls to C<end> before
		657	sending.
		658
		659	The ping example mentioned above is slightly more complicated, as the
		660	there are results to be passwd back, and the number of tasks that are
		661	begung can potentially be zero:
617		662
618	my $cv = AnyEvent->condvar;	663	my $cv = AnyEvent->condvar;
619		664
620	my %result;	665	my %result;
621	$cv->begin (sub { $cv->send (\%result) });	666	$cv->begin (sub { $cv->send (\%result) });
…		…
641	loop, which serves two important purposes: first, it sets the callback	686	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	687	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	688	C<send> is called even when C<no> hosts are being pinged (the loop
644	doesn't execute once).	689	doesn't execute once).
645		690
646	This is the general pattern when you "fan out" into multiple subrequests:	691	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>	692	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	693	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>.	694	subrequest you start, call C<begin> and for each subrequest you finish,
		695	call C<end>.
650		696
651	=back	697	=back
652		698
653	=head3 METHODS FOR CONSUMERS	699	=head3 METHODS FOR CONSUMERS
654		700
…		…
670	function will call C<croak>.	716	function will call C<croak>.
671		717
672	In list context, all parameters passed to C<send> will be returned,	718	In list context, all parameters passed to C<send> will be returned,
673	in scalar context only the first one will be returned.	719	in scalar context only the first one will be returned.
674		720
		721	Note that doing a blocking wait in a callback is not supported by any
		722	event loop, that is, recursive invocation of a blocking C<< ->recv
		723	>> is not allowed, and the C<recv> call will C<croak> if such a
		724	condition is detected. This condition can be slightly loosened by using
		725	L<Coro::AnyEvent>, which allows you to do a blocking C<< ->recv >> from
		726	any thread that doesn't run the event loop itself.
		727
675	Not all event models support a blocking wait - some die in that case	728	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	729	(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	730	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	731	caller decide whether the call will block or not (for example, by coupling
679	condition variables with some kind of request results and supporting	732	condition variables with some kind of request results and supporting
680	callbacks so the caller knows that getting the result will not block,	733	callbacks so the caller knows that getting the result will not block,
681	while still supporting blocking waits if the caller so desires).	734	while still supporting blocking waits if the caller so desires).
682		735
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	736	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	737	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	738	time). This will work even when the event loop does not support blocking
697	waits otherwise.	739	waits otherwise.
698		740
…		…
711	variable itself. Calling C<recv> inside the callback or at any later time	753	variable itself. Calling C<recv> inside the callback or at any later time
712	is guaranteed not to block.	754	is guaranteed not to block.
713		755
714	=back	756	=back
715		757
		758	=head1 SUPPORTED EVENT LOOPS/BACKENDS
		759
		760	The available backend classes are (every class has its own manpage):
		761
		762	=over 4
		763
		764	=item Backends that are autoprobed when no other event loop can be found.
		765
		766	EV is the preferred backend when no other event loop seems to be in
		767	use. If EV is not installed, then AnyEvent will try Event, and, failing
		768	that, will fall back to its own pure-perl implementation, which is
		769	available everywhere as it comes with AnyEvent itself.
		770
		771	AnyEvent::Impl::EV based on EV (interface to libev, best choice).
		772	AnyEvent::Impl::Event based on Event, very stable, few glitches.
		773	AnyEvent::Impl::Perl pure-perl implementation, fast and portable.
		774
		775	=item Backends that are transparently being picked up when they are used.
		776
		777	These will be used when they are currently loaded when the first watcher
		778	is created, in which case it is assumed that the application is using
		779	them. This means that AnyEvent will automatically pick the right backend
		780	when the main program loads an event module before anything starts to
		781	create watchers. Nothing special needs to be done by the main program.
		782
		783	AnyEvent::Impl::Glib based on Glib, slow but very stable.
		784	AnyEvent::Impl::Tk based on Tk, very broken.
		785	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
		786	AnyEvent::Impl::POE based on POE, very slow, some limitations.
		787
		788	=item Backends with special needs.
		789
		790	Qt requires the Qt::Application to be instantiated first, but will
		791	otherwise be picked up automatically. As long as the main program
		792	instantiates the application before any AnyEvent watchers are created,
		793	everything should just work.
		794
		795	AnyEvent::Impl::Qt based on Qt.
		796
		797	Support for IO::Async can only be partial, as it is too broken and
		798	architecturally limited to even support the AnyEvent API. It also
		799	is the only event loop that needs the loop to be set explicitly, so
		800	it can only be used by a main program knowing about AnyEvent. See
		801	L<AnyEvent::Impl::Async> for the gory details.
		802
		803	AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed.
		804
		805	=item Event loops that are indirectly supported via other backends.
		806
		807	Some event loops can be supported via other modules:
		808
		809	There is no direct support for WxWidgets (L<Wx>) or L<Prima>.
		810
		811	B<WxWidgets> has no support for watching file handles. However, you can
		812	use WxWidgets through the POE adaptor, as POE has a Wx backend that simply
		813	polls 20 times per second, which was considered to be too horrible to even
		814	consider for AnyEvent.
		815
		816	B<Prima> is not supported as nobody seems to be using it, but it has a POE
		817	backend, so it can be supported through POE.
		818
		819	AnyEvent knows about both L<Prima> and L<Wx>, however, and will try to
		820	load L<POE> when detecting them, in the hope that POE will pick them up,
		821	in which case everything will be automatic.
		822
		823	=back
		824
716	=head1 GLOBAL VARIABLES AND FUNCTIONS	825	=head1 GLOBAL VARIABLES AND FUNCTIONS
717		826
		827	These are not normally required to use AnyEvent, but can be useful to
		828	write AnyEvent extension modules.
		829
718	=over 4	830	=over 4
719		831
720	=item $AnyEvent::MODEL	832	=item $AnyEvent::MODEL
721		833
722	Contains C<undef> until the first watcher is being created. Then it	834	Contains C<undef> until the first watcher is being created, before the
		835	backend has been autodetected.
		836
723	contains the event model that is being used, which is the name of the	837	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	838	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	839	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>).	840	case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it
727		841	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		842
753	=item AnyEvent::detect	843	=item AnyEvent::detect
754		844
755	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model	845	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model
756	if necessary. You should only call this function right before you would	846	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	847	have created an AnyEvent watcher anyway, that is, as late as possible at
758	runtime.	848	runtime, and not e.g. while initialising of your module.
		849
		850	If you need to do some initialisation before AnyEvent watchers are
		851	created, use C<post_detect>.
759		852
760	=item $guard = AnyEvent::post_detect { BLOCK }	853	=item $guard = AnyEvent::post_detect { BLOCK }
761		854
762	Arranges for the code block to be executed as soon as the event model is	855	Arranges for the code block to be executed as soon as the event model is
763	autodetected (or immediately if this has already happened).	856	autodetected (or immediately if this has already happened).
		857
		858	The block will be executed I<after> the actual backend has been detected
		859	(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been
		860	created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do
		861	other initialisations - see the sources of L<AnyEvent::Strict> or
		862	L<AnyEvent::AIO> to see how this is used.
		863
		864	The most common usage is to create some global watchers, without forcing
		865	event module detection too early, for example, L<AnyEvent::AIO> creates
		866	and installs the global L<IO::AIO> watcher in a C<post_detect> block to
		867	avoid autodetecting the event module at load time.
764		868
765	If called in scalar or list context, then it creates and returns an object	869	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	870	that automatically removes the callback again when it is destroyed. See
767	L<Coro::BDB> for a case where this is useful.	871	L<Coro::BDB> for a case where this is useful.
768		872
…		…
771	If there are any code references in this array (you can C<push> to it	875	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	876	before or after loading AnyEvent), then they will called directly after
773	the event loop has been chosen.	877	the event loop has been chosen.
774		878
775	You should check C<$AnyEvent::MODEL> before adding to this array, though:	879	You should check C<$AnyEvent::MODEL> before adding to this array, though:
776	if it contains a true value then the event loop has already been detected,	880	if it is defined then the event loop has already been detected, and the
777	and the array will be ignored.	881	array will be ignored.
778		882
779	Best use C<AnyEvent::post_detect { BLOCK }> instead.	883	Best use C<AnyEvent::post_detect { BLOCK }> when your application allows
		884	it,as it takes care of these details.
		885
		886	This variable is mainly useful for modules that can do something useful
		887	when AnyEvent is used and thus want to know when it is initialised, but do
		888	not need to even load it by default. This array provides the means to hook
		889	into AnyEvent passively, without loading it.
780		890
781	=back	891	=back
782		892
783	=head1 WHAT TO DO IN A MODULE	893	=head1 WHAT TO DO IN A MODULE
784		894
…		…
839		949
840		950
841	=head1 OTHER MODULES	951	=head1 OTHER MODULES
842		952
843	The following is a non-exhaustive list of additional modules that use	953	The following is a non-exhaustive list of additional modules that use
844	AnyEvent and can therefore be mixed easily with other AnyEvent modules	954	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	955	modules and other event loops in the same program. Some of the modules
846	available via CPAN.	956	come with AnyEvent, most are available via CPAN.
847		957
848	=over 4	958	=over 4
849		959
850	=item L<AnyEvent::Util>	960	=item L<AnyEvent::Util>
851		961
…		…
860		970
861	=item L<AnyEvent::Handle>	971	=item L<AnyEvent::Handle>
862		972
863	Provide read and write buffers, manages watchers for reads and writes,	973	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	974	supports raw and formatted I/O, I/O queued and fully transparent and
865	non-blocking SSL/TLS.	975	non-blocking SSL/TLS (via L<AnyEvent::TLS>.
866		976
867	=item L<AnyEvent::DNS>	977	=item L<AnyEvent::DNS>
868		978
869	Provides rich asynchronous DNS resolver capabilities.	979	Provides rich asynchronous DNS resolver capabilities.
870		980
…		…
898		1008
899	=item L<AnyEvent::GPSD>	1009	=item L<AnyEvent::GPSD>
900		1010
901	A non-blocking interface to gpsd, a daemon delivering GPS information.	1011	A non-blocking interface to gpsd, a daemon delivering GPS information.
902		1012
		1013	=item L<AnyEvent::IRC>
		1014
		1015	AnyEvent based IRC client module family (replacing the older Net::IRC3).
		1016
		1017	=item L<AnyEvent::XMPP>
		1018
		1019	AnyEvent based XMPP (Jabber protocol) module family (replacing the older
		1020	Net::XMPP2>.
		1021
903	=item L<AnyEvent::IGS>	1022	=item L<AnyEvent::IGS>
904		1023
905	A non-blocking interface to the Internet Go Server protocol (used by	1024	A non-blocking interface to the Internet Go Server protocol (used by
906	L<App::IGS>).	1025	L<App::IGS>).
907		1026
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>	1027	=item L<Net::FCP>
917		1028
918	AnyEvent-based implementation of the Freenet Client Protocol, birthplace	1029	AnyEvent-based implementation of the Freenet Client Protocol, birthplace
919	of AnyEvent.	1030	of AnyEvent.
920		1031
…		…
924		1035
925	=item L<Coro>	1036	=item L<Coro>
926		1037
927	Has special support for AnyEvent via L<Coro::AnyEvent>.	1038	Has special support for AnyEvent via L<Coro::AnyEvent>.
928		1039
929	=item L<IO::Lambda>
930
931	The lambda approach to I/O - don't ask, look there. Can use AnyEvent.
932
933	=back	1040	=back
934		1041
935	=cut	1042	=cut
936		1043
937	package AnyEvent;	1044	package AnyEvent;
938		1045
		1046	# basically a tuned-down version of common::sense
		1047	sub common_sense {
939	no warnings;	1048	# no warnings
		1049	${^WARNING_BITS} ^= ${^WARNING_BITS};
940	use strict qw(vars subs);	1050	# use strict vars subs
		1051	$^H \|= 0x00000600;
		1052	}
941		1053
		1054	BEGIN { AnyEvent::common_sense }
		1055
942	use Carp;	1056	use Carp ();
943		1057
944	our $VERSION = 4.412;	1058	our $VERSION = 4.83;
945	our $MODEL;	1059	our $MODEL;
946		1060
947	our $AUTOLOAD;	1061	our $AUTOLOAD;
948	our @ISA;	1062	our @ISA;
949		1063
950	our @REGISTRY;	1064	our @REGISTRY;
951		1065
952	our $WIN32;	1066	our $WIN32;
		1067
		1068	our $VERBOSE;
953		1069
954	BEGIN {	1070	BEGIN {
955	eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }";	1071	eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }";
956	eval "sub TAINT(){ " . (${^TAINT}*1) . " }";	1072	eval "sub TAINT(){ " . (${^TAINT}*1) . " }";
957		1073
958	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}	1074	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}
959	if ${^TAINT};	1075	if ${^TAINT};
960	}
961		1076
962	our $verbose = $ENV{PERL_ANYEVENT_VERBOSE}*1;	1077	$VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1;
		1078
		1079	}
		1080
		1081	our $MAX_SIGNAL_LATENCY = 10;
963		1082
964	our %PROTOCOL; # (ipv4\|ipv6) => (1\|2), higher numbers are preferred	1083	our %PROTOCOL; # (ipv4\|ipv6) => (1\|2), higher numbers are preferred
965		1084
966	{	1085	{
967	my $idx;	1086	my $idx;
…		…
975	[Event:: => AnyEvent::Impl::Event::],	1094	[Event:: => AnyEvent::Impl::Event::],
976	[AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::],	1095	[AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::],
977	# everything below here will not be autoprobed	1096	# everything below here will not be autoprobed
978	# as the pureperl backend should work everywhere	1097	# as the pureperl backend should work everywhere
979	# and is usually faster	1098	# and is usually faster
980	[Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
981	[Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers	1099	[Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers
982	[Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy	1100	[Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
		1101	[Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
983	[Qt:: => AnyEvent::Impl::Qt::], # requires special main program	1102	[Qt:: => AnyEvent::Impl::Qt::], # requires special main program
984	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza	1103	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
985	[Wx:: => AnyEvent::Impl::POE::],	1104	[Wx:: => AnyEvent::Impl::POE::],
986	[Prima:: => AnyEvent::Impl::POE::],	1105	[Prima:: => AnyEvent::Impl::POE::],
987	# IO::Async is just too broken - we would need workaorunds for its	1106	# IO::Async is just too broken - we would need workarounds for its
988	# byzantine signal and broken child handling, among others.	1107	# byzantine signal and broken child handling, among others.
989	# IO::Async is rather hard to detect, as it doesn't have any	1108	# IO::Async is rather hard to detect, as it doesn't have any
990	# obvious default class.	1109	# obvious default class.
991	# [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program	1110	# [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program
992	# [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program	1111	# [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program
…		…
1018	@post_detect = grep $_ != ${$_[0]}, @post_detect;	1137	@post_detect = grep $_ != ${$_[0]}, @post_detect;
1019	}	1138	}
1020		1139
1021	sub detect() {	1140	sub detect() {
1022	unless ($MODEL) {	1141	unless ($MODEL) {
1023	no strict 'refs';
1024	local $SIG{__DIE__};	1142	local $SIG{__DIE__};
1025		1143
1026	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {	1144	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {
1027	my $model = "AnyEvent::Impl::$1";	1145	my $model = "AnyEvent::Impl::$1";
1028	if (eval "require $model") {	1146	if (eval "require $model") {
1029	$MODEL = $model;	1147	$MODEL = $model;
1030	warn "AnyEvent: loaded model '$model' (forced by \$PERL_ANYEVENT_MODEL), using it.\n" if $verbose > 1;	1148	warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2;
1031	} else {	1149	} else {
1032	warn "AnyEvent: unable to load model '$model' (from \$PERL_ANYEVENT_MODEL):\n$@" if $verbose;	1150	warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE;
1033	}	1151	}
1034	}	1152	}
1035		1153
1036	# check for already loaded models	1154	# check for already loaded models
1037	unless ($MODEL) {	1155	unless ($MODEL) {
1038	for (@REGISTRY, @models) {	1156	for (@REGISTRY, @models) {
1039	my ($package, $model) = @$_;	1157	my ($package, $model) = @$_;
1040	if (${"$package\::VERSION"} > 0) {	1158	if (${"$package\::VERSION"} > 0) {
1041	if (eval "require $model") {	1159	if (eval "require $model") {
1042	$MODEL = $model;	1160	$MODEL = $model;
1043	warn "AnyEvent: autodetected model '$model', using it.\n" if $verbose > 1;	1161	warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2;
1044	last;	1162	last;
1045	}	1163	}
1046	}	1164	}
1047	}	1165	}
1048		1166
…		…
1053	my ($package, $model) = @$_;	1171	my ($package, $model) = @$_;
1054	if (eval "require $package"	1172	if (eval "require $package"
1055	and ${"$package\::VERSION"} > 0	1173	and ${"$package\::VERSION"} > 0
1056	and eval "require $model") {	1174	and eval "require $model") {
1057	$MODEL = $model;	1175	$MODEL = $model;
1058	warn "AnyEvent: autoprobed model '$model', using it.\n" if $verbose > 1;	1176	warn "AnyEvent: autoprobed model '$model', using it.\n" if $VERBOSE >= 2;
1059	last;	1177	last;
1060	}	1178	}
1061	}	1179	}
1062		1180
1063	$MODEL	1181	$MODEL
…		…
1079		1197
1080	sub AUTOLOAD {	1198	sub AUTOLOAD {
1081	(my $func = $AUTOLOAD) =~ s/.*://;	1199	(my $func = $AUTOLOAD) =~ s/.*://;
1082		1200
1083	$method{$func}	1201	$method{$func}
1084	or croak "$func: not a valid method for AnyEvent objects";	1202	or Carp::croak "$func: not a valid method for AnyEvent objects";
1085		1203
1086	detect unless $MODEL;	1204	detect unless $MODEL;
1087		1205
1088	my $class = shift;	1206	my $class = shift;
1089	$class->$func (@_);	1207	$class->$func (@_);
…		…
1094	# allow only one watcher per fd, so we dup it to get a different one).	1212	# allow only one watcher per fd, so we dup it to get a different one).
1095	sub _dupfh($$;$$) {	1213	sub _dupfh($$;$$) {
1096	my ($poll, $fh, $r, $w) = @_;	1214	my ($poll, $fh, $r, $w) = @_;
1097		1215
1098	# cygwin requires the fh mode to be matching, unix doesn't	1216	# cygwin requires the fh mode to be matching, unix doesn't
1099	my ($rw, $mode) = $poll eq "r" ? ($r, "<")	1217	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		1218
1103	open my $fh2, "$mode&" . fileno $fh	1219	open my $fh2, $mode, $fh
1104	or die "cannot dup() filehandle: $!,";	1220	or die "AnyEvent->io: cannot dup() filehandle in mode '$poll': $!,";
1105		1221
1106	# we assume CLOEXEC is already set by perl in all important cases	1222	# we assume CLOEXEC is already set by perl in all important cases
1107		1223
1108	($fh2, $rw)	1224	($fh2, $rw)
1109	}	1225	}
1110		1226
1111	package AnyEvent::Base;	1227	package AnyEvent::Base;
1112		1228
1113	# default implementations for many methods	1229	# default implementations for many methods
1114		1230
1115	BEGIN {	1231	sub _time {
		1232	# probe for availability of Time::HiRes
1116	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {	1233	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
		1234	warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8;
1117	*_time = \&Time::HiRes::time;	1235	*_time = \&Time::HiRes::time;
1118	# if (eval "use POSIX (); (POSIX::times())...	1236	# if (eval "use POSIX (); (POSIX::times())...
1119	} else {	1237	} else {
		1238	warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE;
1120	*_time = sub { time }; # epic fail	1239	*_time = sub { time }; # epic fail
1121	}	1240	}
		1241
		1242	&_time
1122	}	1243	}
1123		1244
1124	sub time { _time }	1245	sub time { _time }
1125	sub now { _time }	1246	sub now { _time }
1126	sub now_update { }	1247	sub now_update { }
…		…
1131	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"	1252	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"
1132	}	1253	}
1133		1254
1134	# default implementation for ->signal	1255	# default implementation for ->signal
1135		1256
		1257	our $HAVE_ASYNC_INTERRUPT;
1136	our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);	1258	our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);
		1259	our (%SIG_ASY, %SIG_ASY_W);
		1260	our ($SIG_COUNT, $SIG_TW);
1137		1261
1138	sub _signal_exec {	1262	sub _signal_exec {
		1263	$HAVE_ASYNC_INTERRUPT
		1264	? $SIGPIPE_R->drain
1139	sysread $SIGPIPE_R, my $dummy, 4;	1265	: sysread $SIGPIPE_R, my $dummy, 9;
1140		1266
1141	while (%SIG_EV) {	1267	while (%SIG_EV) {
1142	for (keys %SIG_EV) {	1268	for (keys %SIG_EV) {
1143	delete $SIG_EV{$_};	1269	delete $SIG_EV{$_};
1144	$_->() for values %{ $SIG_CB{$_} \|\| {} };	1270	$_->() for values %{ $SIG_CB{$_} \|\| {} };
1145	}	1271	}
1146	}	1272	}
1147	}	1273	}
1148		1274
		1275	sub _signal {
		1276	my (undef, %arg) = @_;
		1277
		1278	my $signal = uc $arg{signal}
		1279	or Carp::croak "required option 'signal' is missing";
		1280
		1281	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};
		1282
		1283	if ($HAVE_ASYNC_INTERRUPT) {
		1284	# async::interrupt
		1285
		1286	$SIG_ASY{$signal} \|\|= do {
		1287	my $asy = new Async::Interrupt
		1288	cb => sub { undef $SIG_EV{$signal} },
		1289	signal => $signal,
		1290	pipe => [$SIGPIPE_R->filenos],
		1291	;
		1292	$asy->pipe_autodrain (0);
		1293
		1294	$asy
		1295	};
		1296
		1297	} else {
		1298	# pure perl
		1299
		1300	$SIG{$signal} \|\|= sub {
		1301	local $!;
		1302	syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
		1303	undef $SIG_EV{$signal};
		1304	};
		1305
		1306	# can't do signal processing without introducing races in pure perl,
		1307	# so limit the signal latency.
		1308	++$SIG_COUNT;
		1309	$SIG_TW \|\|= AnyEvent->timer (
		1310	after => $MAX_SIGNAL_LATENCY,
		1311	interval => $MAX_SIGNAL_LATENCY,
		1312	cb => sub { }, # just for the PERL_ASYNC_CHECK
		1313	);
		1314	}
		1315
		1316	bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
		1317	}
		1318
1149	sub signal {	1319	sub signal {
1150	my (undef, %arg) = @_;	1320	# probe for availability of Async::Interrupt
		1321	if (!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT} && eval "use Async::Interrupt 0.6 (); 1") {
		1322	warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8;
1151		1323
1152	unless ($SIGPIPE_R) {	1324	$HAVE_ASYNC_INTERRUPT = 1;
		1325	$SIGPIPE_R = new Async::Interrupt::EventPipe;
		1326	$SIG_IO = AnyEvent->io (fh => $SIGPIPE_R->fileno, poll => "r", cb => \&_signal_exec);
		1327
		1328	} else {
		1329	warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;
		1330
1153	require Fcntl;	1331	require Fcntl;
1154		1332
1155	if (AnyEvent::WIN32) {	1333	if (AnyEvent::WIN32) {
1156	require AnyEvent::Util;	1334	require AnyEvent::Util;
1157		1335
…		…
1172	or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";	1350	or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1173		1351
1174	$SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec);	1352	$SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec);
1175	}	1353	}
1176		1354
1177	my $signal = uc $arg{signal}	1355	*signal = \&_signal;
1178	or Carp::croak "required option 'signal' is missing";	1356	&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, $arg{cb}], "AnyEvent::Base::signal"
1188	}	1357	}
1189		1358
1190	sub AnyEvent::Base::signal::DESTROY {	1359	sub AnyEvent::Base::signal::DESTROY {
1191	my ($signal, $cb) = @{$_[0]};	1360	my ($signal, $cb) = @{$_[0]};
		1361
		1362	undef $SIG_TW
		1363	unless --$SIG_COUNT;
1192		1364
1193	delete $SIG_CB{$signal}{$cb};	1365	delete $SIG_CB{$signal}{$cb};
1194		1366
1195	# delete doesn't work with older perls - they then	1367	# delete doesn't work with older perls - they then
1196	# print weird messages, or just unconditionally exit	1368	# print weird messages, or just unconditionally exit
1197	# instead of getting the default action.	1369	# instead of getting the default action.
		1370	undef $SIG{$signal}
1198	undef $SIG{$signal} unless keys %{ $SIG_CB{$signal} };	1371	unless keys %{ $SIG_CB{$signal} };
1199	}	1372	}
1200		1373
1201	# default implementation for ->child	1374	# default implementation for ->child
1202		1375
1203	our %PID_CB;	1376	our %PID_CB;
…		…
1205	our $CHLD_DELAY_W;	1378	our $CHLD_DELAY_W;
1206	our $WNOHANG;	1379	our $WNOHANG;
1207		1380
1208	sub _sigchld {	1381	sub _sigchld {
1209	while (0 < (my $pid = waitpid -1, $WNOHANG)) {	1382	while (0 < (my $pid = waitpid -1, $WNOHANG)) {
		1383	$_->($pid, $?)
1210	$_->($pid, $?) for (values %{ $PID_CB{$pid} \|\| {} }),	1384	for values %{ $PID_CB{$pid} \|\| {} },
1211	(values %{ $PID_CB{0} \|\| {} });	1385	values %{ $PID_CB{0} \|\| {} };
1212	}	1386	}
1213	}	1387	}
1214		1388
1215	sub child {	1389	sub child {
1216	my (undef, %arg) = @_;	1390	my (undef, %arg) = @_;
…		…
1218	defined (my $pid = $arg{pid} + 0)	1392	defined (my $pid = $arg{pid} + 0)
1219	or Carp::croak "required option 'pid' is missing";	1393	or Carp::croak "required option 'pid' is missing";
1220		1394
1221	$PID_CB{$pid}{$arg{cb}} = $arg{cb};	1395	$PID_CB{$pid}{$arg{cb}} = $arg{cb};
1222		1396
		1397	# WNOHANG is almost cetrainly 1 everywhere
		1398	$WNOHANG \|\|= $^O =~ /^(?:openbsd\|netbsd\|linux\|freebsd\|cygwin\|MSWin32)$/
		1399	? 1
1223	$WNOHANG \|\|= eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } \|\| 1;	1400	: eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } \|\| 1;
1224		1401
1225	unless ($CHLD_W) {	1402	unless ($CHLD_W) {
1226	$CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld);	1403	$CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld);
1227	# child could be a zombie already, so make at least one round	1404	# child could be a zombie already, so make at least one round
1228	&_sigchld;	1405	&_sigchld;
…		…
1280		1457
1281	our @ISA = AnyEvent::CondVar::Base::;	1458	our @ISA = AnyEvent::CondVar::Base::;
1282		1459
1283	package AnyEvent::CondVar::Base;	1460	package AnyEvent::CondVar::Base;
1284		1461
1285	use overload	1462	#use overload
1286	'&{}' => sub { my $self = shift; sub { $self->send (@_) } },	1463	# '&{}' => sub { my $self = shift; sub { $self->send (@_) } },
1287	fallback => 1;	1464	# fallback => 1;
		1465
		1466	# save 300+ kilobytes by dirtily hardcoding overloading
		1467	${"AnyEvent::CondVar::Base::OVERLOAD"}{dummy}++; # Register with magic by touching.
		1468	*{'AnyEvent::CondVar::Base::()'} = sub { }; # "Make it findable via fetchmethod."
		1469	*{'AnyEvent::CondVar::Base::(&{}'} = sub { my $self = shift; sub { $self->send (@_) } }; # &{}
		1470	${'AnyEvent::CondVar::Base::()'} = 1; # fallback
		1471
		1472	our $WAITING;
1288		1473
1289	sub _send {	1474	sub _send {
1290	# nop	1475	# nop
1291	}	1476	}
1292		1477
…		…
1305	sub ready {	1490	sub ready {
1306	$_[0]{_ae_sent}	1491	$_[0]{_ae_sent}
1307	}	1492	}
1308		1493
1309	sub _wait {	1494	sub _wait {
		1495	$WAITING
		1496	and !$_[0]{_ae_sent}
		1497	and Carp::croak "AnyEvent::CondVar: recursive blocking wait detected";
		1498
		1499	local $WAITING = 1;
1310	AnyEvent->one_event while !$_[0]{_ae_sent};	1500	AnyEvent->one_event while !$_[0]{_ae_sent};
1311	}	1501	}
1312		1502
1313	sub recv {	1503	sub recv {
1314	$_[0]->_wait;	1504	$_[0]->_wait;
…		…
1386	check the arguments passed to most method calls. If it finds any problems,	1576	check the arguments passed to most method calls. If it finds any problems,
1387	it will croak.	1577	it will croak.
1388		1578
1389	In other words, enables "strict" mode.	1579	In other words, enables "strict" mode.
1390		1580
1391	Unlike C<use strict>, it is definitely recommended to keep it off in	1581	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	1582	>>, it is definitely recommended to keep it off in production. Keeping
1393	developing programs can be very useful, however.	1583	C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs
		1584	can be very useful, however.
1394		1585
1395	=item C<PERL_ANYEVENT_MODEL>	1586	=item C<PERL_ANYEVENT_MODEL>
1396		1587
1397	This can be used to specify the event model to be used by AnyEvent, before	1588	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	1589	auto detection and -probing kicks in. It must be a string consisting
…		…
1441		1632
1442	=item C<PERL_ANYEVENT_MAX_FORKS>	1633	=item C<PERL_ANYEVENT_MAX_FORKS>
1443		1634
1444	The maximum number of child processes that C<AnyEvent::Util::fork_call>	1635	The maximum number of child processes that C<AnyEvent::Util::fork_call>
1445	will create in parallel.	1636	will create in parallel.
		1637
		1638	=item C<PERL_ANYEVENT_MAX_OUTSTANDING_DNS>
		1639
		1640	The default value for the C<max_outstanding> parameter for the default DNS
		1641	resolver - this is the maximum number of parallel DNS requests that are
		1642	sent to the DNS server.
		1643
		1644	=item C<PERL_ANYEVENT_RESOLV_CONF>
		1645
		1646	The file to use instead of F</etc/resolv.conf> (or OS-specific
		1647	configuration) in the default resolver. When set to the empty string, no
		1648	default config will be used.
		1649
		1650	=item C<PERL_ANYEVENT_CA_FILE>, C<PERL_ANYEVENT_CA_PATH>.
		1651
		1652	When neither C<ca_file> nor C<ca_path> was specified during
		1653	L<AnyEvent::TLS> context creation, and either of these environment
		1654	variables exist, they will be used to specify CA certificate locations
		1655	instead of a system-dependent default.
1446		1656
1447	=back	1657	=back
1448		1658
1449	=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE	1659	=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE
1450		1660
…		…
1695	EV/Any 100000 224 2.88 0.34 0.27 EV + AnyEvent watchers	1905	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	1906	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	1907	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	1908	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	1909	Event/Any 16000 590 35.85 31.55 1.06 Event + AnyEvent watchers
		1910	IOAsync/Any 16000 989 38.10 32.77 11.13 via IO::Async::Loop::IO_Poll
		1911	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	1912	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	1913	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	1914	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	1915	POE/Select 2000 6027 94.54 809.13 579.80 via POE::Loop::Select
1704		1916
…		…
1733	performance becomes really bad with lots of file descriptors (and few of	1945	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.	1946	them active), of course, but this was not subject of this benchmark.
1735		1947
1736	The C<Event> module has a relatively high setup and callback invocation	1948	The C<Event> module has a relatively high setup and callback invocation
1737	cost, but overall scores in on the third place.	1949	cost, but overall scores in on the third place.
		1950
		1951	C<IO::Async> performs admirably well, about on par with C<Event>, even
		1952	when using its pure perl backend.
1738		1953
1739	C<Glib>'s memory usage is quite a bit higher, but it features a	1954	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	1955	faster callback invocation and overall ends up in the same class as
1741	C<Event>. However, Glib scales extremely badly, doubling the number of	1956	C<Event>. However, Glib scales extremely badly, doubling the number of
1742	watchers increases the processing time by more than a factor of four,	1957	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	2035	it to another server. This includes deleting the old timeout and creating
1821	a new one that moves the timeout into the future.	2036	a new one that moves the timeout into the future.
1822		2037
1823	=head3 Results	2038	=head3 Results
1824		2039
1825	name sockets create request	2040	name sockets create request
1826	EV 20000 69.01 11.16	2041	EV 20000 69.01 11.16
1827	Perl 20000 73.32 35.87	2042	Perl 20000 73.32 35.87
		2043	IOAsync 20000 157.00 98.14 epoll
		2044	IOAsync 20000 159.31 616.06 poll
1828	Event 20000 212.62 257.32	2045	Event 20000 212.62 257.32
1829	Glib 20000 651.16 1896.30	2046	Glib 20000 651.16 1896.30
1830	POE 20000 349.67 12317.24 uses POE::Loop::Event	2047	POE 20000 349.67 12317.24 uses POE::Loop::Event
1831		2048
1832	=head3 Discussion	2049	=head3 Discussion
1833		2050
1834	This benchmark I<does> measure scalability and overall performance of the	2051	This benchmark I<does> measure scalability and overall performance of the
1835	particular event loop.	2052	particular event loop.
…		…
1837	EV is again fastest. Since it is using epoll on my system, the setup time	2054	EV is again fastest. Since it is using epoll on my system, the setup time
1838	is relatively high, though.	2055	is relatively high, though.
1839		2056
1840	Perl surprisingly comes second. It is much faster than the C-based event	2057	Perl surprisingly comes second. It is much faster than the C-based event
1841	loops Event and Glib.	2058	loops Event and Glib.
		2059
		2060	IO::Async performs very well when using its epoll backend, and still quite
		2061	good compared to Glib when using its pure perl backend.
1842		2062
1843	Event suffers from high setup time as well (look at its code and you will	2063	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	2064	understand why). Callback invocation also has a high overhead compared to
1845	the C<< $_->() for .. >>-style loop that the Perl event loop uses. Event	2065	the C<< $_->() for .. >>-style loop that the Perl event loop uses. Event
1846	uses select or poll in basically all documented configurations.	2066	uses select or poll in basically all documented configurations.
…		…
1979		2199
1980	A handler for C<SIGCHLD> is installed by AnyEvent's child watcher	2200	A handler for C<SIGCHLD> is installed by AnyEvent's child watcher
1981	emulation for event loops that do not support them natively. Also, some	2201	emulation for event loops that do not support them natively. Also, some
1982	event loops install a similar handler.	2202	event loops install a similar handler.
1983		2203
1984	If, when AnyEvent is loaded, SIGCHLD is set to IGNORE, then AnyEvent will	2204	Additionally, when AnyEvent is loaded and SIGCHLD is set to IGNORE, then
1985	reset it to default, to avoid losing child exit statuses.	2205	AnyEvent will reset it to default, to avoid losing child exit statuses.
1986		2206
1987	=item SIGPIPE	2207	=item SIGPIPE
1988		2208
1989	A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef>	2209	A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef>
1990	when AnyEvent gets loaded.	2210	when AnyEvent gets loaded.
…		…
2008	if $SIG{CHLD} eq 'IGNORE';	2228	if $SIG{CHLD} eq 'IGNORE';
2009		2229
2010	$SIG{PIPE} = sub { }	2230	$SIG{PIPE} = sub { }
2011	unless defined $SIG{PIPE};	2231	unless defined $SIG{PIPE};
2012		2232
		2233	=head1 RECOMMENDED/OPTIONAL MODULES
		2234
		2235	One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and
		2236	it's built-in modules) are required to use it.
		2237
		2238	That does not mean that AnyEvent won't take advantage of some additional
		2239	modules if they are installed.
		2240
		2241	This section epxlains which additional modules will be used, and how they
		2242	affect AnyEvent's operetion.
		2243
		2244	=over 4
		2245
		2246	=item L<Async::Interrupt>
		2247
		2248	This slightly arcane module is used to implement fast signal handling: To
		2249	my knowledge, there is no way to do completely race-free and quick
		2250	signal handling in pure perl. To ensure that signals still get
		2251	delivered, AnyEvent will start an interval timer to wake up perl (and
		2252	catch the signals) with soemd elay (default is 10 seconds, look for
		2253	C<$AnyEvent::MAX_SIGNAL_LATENCY>).
		2254
		2255	If this module is available, then it will be used to implement signal
		2256	catching, which means that signals will not be delayed, and the event loop
		2257	will not be interrupted regularly, which is more efficient (And good for
		2258	battery life on laptops).
		2259
		2260	This affects not just the pure-perl event loop, but also other event loops
		2261	that have no signal handling on their own (e.g. Glib, Tk, Qt).
		2262
		2263	=item L<EV>
		2264
		2265	This module isn't really "optional", as it is simply one of the backend
		2266	event loops that AnyEvent can use. However, it is simply the best event
		2267	loop available in terms of features, speed and stability: It supports
		2268	the AnyEvent API optimally, implements all the watcher types in XS, does
		2269	automatic timer adjustments even when no monotonic clock is available,
		2270	can take avdantage of advanced kernel interfaces such as C<epoll> and
		2271	C<kqueue>, and is the fastest backend I<by far>. You can even embed
		2272	L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>).
		2273
		2274	=item L<Guard>
		2275
		2276	The guard module, when used, will be used to implement
		2277	C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a
		2278	lot less memory), but otherwise doesn't affect guard operation much. It is
		2279	purely used for performance.
		2280
		2281	=item L<JSON> and L<JSON::XS>
		2282
		2283	This module is required when you want to read or write JSON data via
		2284	L<AnyEvent::Handle>. It is also written in pure-perl, but can take
		2285	advantage of the ulta-high-speed L<JSON::XS> module when it is installed.
		2286
		2287	In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is
		2288	installed.
		2289
		2290	=item L<Net::SSLeay>
		2291
		2292	Implementing TLS/SSL in Perl is certainly interesting, but not very
		2293	worthwhile: If this module is installed, then L<AnyEvent::Handle> (with
		2294	the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL.
		2295
		2296	=item L<Time::HiRes>
		2297
		2298	This module is part of perl since release 5.008. It will be used when the
		2299	chosen event library does not come with a timing source on it's own. The
		2300	pure-perl event loop (L<AnyEvent::Impl::Perl>) will additionally use it to
		2301	try to use a monotonic clock for timing stability.
		2302
		2303	=back
		2304
		2305
2013	=head1 FORK	2306	=head1 FORK
2014		2307
2015	Most event libraries are not fork-safe. The ones who are usually are	2308	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>	2309	because they rely on inefficient but fork-safe C<select> or C<poll>
2017	calls. Only L<EV> is fully fork-aware.	2310	calls. Only L<EV> is fully fork-aware.
2018		2311
2019	If you have to fork, you must either do so I<before> creating your first	2312	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.	2313	watcher OR you must not use AnyEvent at all in the child OR you must do
		2314	something completely out of the scope of AnyEvent.
2021		2315
2022		2316
2023	=head1 SECURITY CONSIDERATIONS	2317	=head1 SECURITY CONSIDERATIONS
2024		2318
2025	AnyEvent can be forced to load any event model via	2319	AnyEvent can be forced to load any event model via
…		…
2063	L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.	2357	L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.
2064		2358
2065	Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,	2359	Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,
2066	L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,	2360	L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,
2067	L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,	2361	L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,
2068	L<AnyEvent::Impl::POE>.	2362	L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>.
2069		2363
2070	Non-blocking file handles, sockets, TCP clients and	2364	Non-blocking file handles, sockets, TCP clients and
2071	servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>.	2365	servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.
2072		2366
2073	Asynchronous DNS: L<AnyEvent::DNS>.	2367	Asynchronous DNS: L<AnyEvent::DNS>.
2074		2368
2075	Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>,	2369	Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>,
		2370	L<Coro::Event>,
2076		2371
2077	Nontrivial usage examples: L<Net::FCP>, L<Net::XMPP2>, L<AnyEvent::DNS>.	2372	Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::XMPP>,
		2373	L<AnyEvent::HTTP>.
2078		2374
2079		2375
2080	=head1 AUTHOR	2376	=head1 AUTHOR
2081		2377
2082	Marc Lehmann <schmorp@schmorp.de>	2378	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 1.243 by root, Fri Jul 17 23:12:20 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 1.243 by root, Fri Jul 17 23:12:20 2009 UTC