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

Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.244 by root, Fri Jul 17 23:15:57 2009 UTC vs.
Revision 1.329 by root, Sun Jul 11 05:44:22 2010 UTC

…		…
1	=head1 NAME	1	=head1 NAME
2		2
3	AnyEvent - provide framework for multiple event loops	3	AnyEvent - the DBI of event loop programming
4		4
5	EV, Event, Glib, Tk, Perl, Event::Lib, Qt and POE are various supported	5	EV, Event, Glib, Tk, Perl, Event::Lib, Irssi, rxvt-unicode, IO::Async, Qt
6	event loops.	6	and POE are various supported event loops/environments.
7		7
8	=head1 SYNOPSIS	8	=head1 SYNOPSIS
9		9
10	use AnyEvent;	10	use AnyEvent;
11		11
		12	# if you prefer function calls, look at the AE manpage for
		13	# an alternative API.
		14
12	# file descriptor readable	15	# file handle or descriptor readable
13	my $w = AnyEvent->io (fh => $fh, poll => "r", cb => sub { ... });	16	my $w = AnyEvent->io (fh => $fh, poll => "r", cb => sub { ... });
14		17
15	# one-shot or repeating timers	18	# one-shot or repeating timers
16	my $w = AnyEvent->timer (after => $seconds, cb => sub { ... });	19	my $w = AnyEvent->timer (after => $seconds, cb => sub { ... });
17	my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ...	20	my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ...
40	=head1 INTRODUCTION/TUTORIAL	43	=head1 INTRODUCTION/TUTORIAL
41		44
42	This manpage is mainly a reference manual. If you are interested	45	This manpage is mainly a reference manual. If you are interested
43	in a tutorial or some gentle introduction, have a look at the	46	in a tutorial or some gentle introduction, have a look at the
44	L<AnyEvent::Intro> manpage.	47	L<AnyEvent::Intro> manpage.
		48
		49	=head1 SUPPORT
		50
		51	There is a mailinglist for discussing all things AnyEvent, and an IRC
		52	channel, too.
		53
		54	See the AnyEvent project page at the B<Schmorpforge Ta-Sa Software
		55	Repository>, at L<http://anyevent.schmorp.de>, for more info.
45		56
46	=head1 WHY YOU SHOULD USE THIS MODULE (OR NOT)	57	=head1 WHY YOU SHOULD USE THIS MODULE (OR NOT)
47		58
48	Glib, POE, IO::Async, Event... CPAN offers event models by the dozen	59	Glib, POE, IO::Async, Event... CPAN offers event models by the dozen
49	nowadays. So what is different about AnyEvent?	60	nowadays. So what is different about AnyEvent?
…		…
127	use AnyEvent;	138	use AnyEvent;
128		139
129	# .. AnyEvent will likely default to Tk	140	# .. AnyEvent will likely default to Tk
130		141
131	The I<likely> means that, if any module loads another event model and	142	The I<likely> means that, if any module loads another event model and
132	starts using it, all bets are off. Maybe you should tell their authors to	143	starts using it, all bets are off - this case should be very rare though,
133	use AnyEvent so their modules work together with others seamlessly...	144	as very few modules hardcode event loops without announcing this very
		145	loudly.
134		146
135	The pure-perl implementation of AnyEvent is called	147	The pure-perl implementation of AnyEvent is called
136	C<AnyEvent::Impl::Perl>. Like other event modules you can load it	148	C<AnyEvent::Impl::Perl>. Like other event modules you can load it
137	explicitly and enjoy the high availability of that event loop :)	149	explicitly and enjoy the high availability of that event loop :)
138		150
…		…
172	Note that C<my $w; $w => combination. This is necessary because in Perl,	184	Note that C<my $w; $w => combination. This is necessary because in Perl,
173	my variables are only visible after the statement in which they are	185	my variables are only visible after the statement in which they are
174	declared.	186	declared.
175		187
176	=head2 I/O WATCHERS	188	=head2 I/O WATCHERS
		189
		190	$w = AnyEvent->io (
		191	fh => <filehandle_or_fileno>,
		192	poll => <"r" or "w">,
		193	cb => <callback>,
		194	);
177		195
178	You can create an I/O watcher by calling the C<< AnyEvent->io >> method	196	You can create an I/O watcher by calling the C<< AnyEvent->io >> method
179	with the following mandatory key-value pairs as arguments:	197	with the following mandatory key-value pairs as arguments:
180		198
181	C<fh> is the Perl I<file handle> (or a naked file descriptor) to watch	199	C<fh> is the Perl I<file handle> (or a naked file descriptor) to watch
…		…
211	undef $w;	229	undef $w;
212	});	230	});
213		231
214	=head2 TIME WATCHERS	232	=head2 TIME WATCHERS
215		233
		234	$w = AnyEvent->timer (after => <seconds>, cb => <callback>);
		235
		236	$w = AnyEvent->timer (
		237	after => <fractional_seconds>,
		238	interval => <fractional_seconds>,
		239	cb => <callback>,
		240	);
		241
216	You can create a time watcher by calling the C<< AnyEvent->timer >>	242	You can create a time watcher by calling the C<< AnyEvent->timer >>
217	method with the following mandatory arguments:	243	method with the following mandatory arguments:
218		244
219	C<after> specifies after how many seconds (fractional values are	245	C<after> specifies after how many seconds (fractional values are
220	supported) the callback should be invoked. C<cb> is the callback to invoke	246	supported) the callback should be invoked. C<cb> is the callback to invoke
…		…
341	might affect timers and time-outs.	367	might affect timers and time-outs.
342		368
343	When this is the case, you can call this method, which will update the	369	When this is the case, you can call this method, which will update the
344	event loop's idea of "current time".	370	event loop's idea of "current time".
345		371
		372	A typical example would be a script in a web server (e.g. C<mod_perl>) -
		373	when mod_perl executes the script, then the event loop will have the wrong
		374	idea about the "current time" (being potentially far in the past, when the
		375	script ran the last time). In that case you should arrange a call to C<<
		376	AnyEvent->now_update >> each time the web server process wakes up again
		377	(e.g. at the start of your script, or in a handler).
		378
346	Note that updating the time I<might> cause some events to be handled.	379	Note that updating the time I<might> cause some events to be handled.
347		380
348	=back	381	=back
349		382
350	=head2 SIGNAL WATCHERS	383	=head2 SIGNAL WATCHERS
		384
		385	$w = AnyEvent->signal (signal => <uppercase_signal_name>, cb => <callback>);
351		386
352	You can watch for signals using a signal watcher, C<signal> is the signal	387	You can watch for signals using a signal watcher, C<signal> is the signal
353	I<name> in uppercase and without any C<SIG> prefix, C<cb> is the Perl	388	I<name> in uppercase and without any C<SIG> prefix, C<cb> is the Perl
354	callback to be invoked whenever a signal occurs.	389	callback to be invoked whenever a signal occurs.
355		390
…		…
368		403
369	This watcher might use C<%SIG> (depending on the event loop used),	404	This watcher might use C<%SIG> (depending on the event loop used),
370	so programs overwriting those signals directly will likely not work	405	so programs overwriting those signals directly will likely not work
371	correctly.	406	correctly.
372		407
		408	Example: exit on SIGINT
		409
		410	my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
		411
		412	=head3 Restart Behaviour
		413
		414	While restart behaviour is up to the event loop implementation, most will
		415	not restart syscalls (that includes L<Async::Interrupt> and AnyEvent's
		416	pure perl implementation).
		417
		418	=head3 Safe/Unsafe Signals
		419
		420	Perl signals can be either "safe" (synchronous to opcode handling) or
		421	"unsafe" (asynchronous) - the former might get delayed indefinitely, the
		422	latter might corrupt your memory.
		423
		424	AnyEvent signal handlers are, in addition, synchronous to the event loop,
		425	i.e. they will not interrupt your running perl program but will only be
		426	called as part of the normal event handling (just like timer, I/O etc.
		427	callbacks, too).
		428
		429	=head3 Signal Races, Delays and Workarounds
		430
373	Also note that many event loops (e.g. Glib, Tk, Qt, IO::Async) do not	431	Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching
374	support attaching callbacks to signals, which is a pity, as you cannot do	432	callbacks to signals in a generic way, which is a pity, as you cannot
375	race-free signal handling in perl. AnyEvent will try to do it's best, but	433	do race-free signal handling in perl, requiring C libraries for
		434	this. AnyEvent will try to do it's best, which means in some cases,
376	in some cases, signals will be delayed. The maximum time a signal might	435	signals will be delayed. The maximum time a signal might be delayed is
377	be delayed is specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10	436	specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This
378	seconds). This variable can be changed only before the first signal	437	variable can be changed only before the first signal watcher is created,
379	watcher is created, and should be left alone otherwise. Higher values	438	and should be left alone otherwise. This variable determines how often
		439	AnyEvent polls for signals (in case a wake-up was missed). Higher values
380	will cause fewer spurious wake-ups, which is better for power and CPU	440	will cause fewer spurious wake-ups, which is better for power and CPU
		441	saving.
		442
381	saving. All these problems can be avoided by installing the optional	443	All these problems can be avoided by installing the optional
382	L<Async::Interrupt> module.	444	L<Async::Interrupt> module, which works with most event loops. It will not
383		445	work with inherently broken event loops such as L<Event> or L<Event::Lib>
384	Example: exit on SIGINT	446	(and not with L<POE> currently, as POE does it's own workaround with
385		447	one-second latency). For those, you just have to suffer the delays.
386	my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
387		448
388	=head2 CHILD PROCESS WATCHERS	449	=head2 CHILD PROCESS WATCHERS
389		450
		451	$w = AnyEvent->child (pid => <process id>, cb => <callback>);
		452
390	You can also watch on a child process exit and catch its exit status.	453	You can also watch on a child process exit and catch its exit status.
391		454
392	The child process is specified by the C<pid> argument (if set to C<0>, it	455	The child process is specified by the C<pid> argument (one some backends,
393	watches for any child process exit). The watcher will triggered only when	456	using C<0> watches for any child process exit, on others this will
394	the child process has finished and an exit status is available, not on	457	croak). The watcher will be triggered only when the child process has
395	any trace events (stopped/continued).	458	finished and an exit status is available, not on any trace events
		459	(stopped/continued).
396		460
397	The callback will be called with the pid and exit status (as returned by	461	The callback will be called with the pid and exit status (as returned by
398	waitpid), so unlike other watcher types, you I<can> rely on child watcher	462	waitpid), so unlike other watcher types, you I<can> rely on child watcher
399	callback arguments.	463	callback arguments.
400		464
…		…
441	# do something else, then wait for process exit	505	# do something else, then wait for process exit
442	$done->recv;	506	$done->recv;
443		507
444	=head2 IDLE WATCHERS	508	=head2 IDLE WATCHERS
445		509
446	Sometimes there is a need to do something, but it is not so important	510	$w = AnyEvent->idle (cb => <callback>);
447	to do it instantly, but only when there is nothing better to do. This
448	"nothing better to do" is usually defined to be "no other events need
449	attention by the event loop".
450		511
451	Idle watchers ideally get invoked when the event loop has nothing	512	Repeatedly invoke the callback after the process becomes idle, until
452	better to do, just before it would block the process to wait for new	513	either the watcher is destroyed or new events have been detected.
453	events. Instead of blocking, the idle watcher is invoked.
454		514
455	Most event loops unfortunately do not really support idle watchers (only	515	Idle watchers are useful when there is a need to do something, but it
		516	is not so important (or wise) to do it instantly. The callback will be
		517	invoked only when there is "nothing better to do", which is usually
		518	defined as "all outstanding events have been handled and no new events
		519	have been detected". That means that idle watchers ideally get invoked
		520	when the event loop has just polled for new events but none have been
		521	detected. Instead of blocking to wait for more events, the idle watchers
		522	will be invoked.
		523
		524	Unfortunately, most event loops do not really support idle watchers (only
456	EV, Event and Glib do it in a usable fashion) - for the rest, AnyEvent	525	EV, Event and Glib do it in a usable fashion) - for the rest, AnyEvent
457	will simply call the callback "from time to time".	526	will simply call the callback "from time to time".
458		527
459	Example: read lines from STDIN, but only process them when the	528	Example: read lines from STDIN, but only process them when the
460	program is otherwise idle:	529	program is otherwise idle:
…		…
476	});	545	});
477	});	546	});
478		547
479	=head2 CONDITION VARIABLES	548	=head2 CONDITION VARIABLES
480		549
		550	$cv = AnyEvent->condvar;
		551
		552	$cv->send (<list>);
		553	my @res = $cv->recv;
		554
481	If you are familiar with some event loops you will know that all of them	555	If you are familiar with some event loops you will know that all of them
482	require you to run some blocking "loop", "run" or similar function that	556	require you to run some blocking "loop", "run" or similar function that
483	will actively watch for new events and call your callbacks.	557	will actively watch for new events and call your callbacks.
484		558
485	AnyEvent is slightly different: it expects somebody else to run the event	559	AnyEvent is slightly different: it expects somebody else to run the event
486	loop and will only block when necessary (usually when told by the user).	560	loop and will only block when necessary (usually when told by the user).
487		561
488	The instrument to do that is called a "condition variable", so called	562	The tool to do that is called a "condition variable", so called because
489	because they represent a condition that must become true.	563	they represent a condition that must become true.
490		564
491	Now is probably a good time to look at the examples further below.	565	Now is probably a good time to look at the examples further below.
492		566
493	Condition variables can be created by calling the C<< AnyEvent->condvar	567	Condition variables can be created by calling the C<< AnyEvent->condvar
494	>> method, usually without arguments. The only argument pair allowed is	568	>> method, usually without arguments. The only argument pair allowed is
…		…
499	After creation, the condition variable is "false" until it becomes "true"	573	After creation, the condition variable is "false" until it becomes "true"
500	by calling the C<send> method (or calling the condition variable as if it	574	by calling the C<send> method (or calling the condition variable as if it
501	were a callback, read about the caveats in the description for the C<<	575	were a callback, read about the caveats in the description for the C<<
502	->send >> method).	576	->send >> method).
503		577
504	Condition variables are similar to callbacks, except that you can	578	Since condition variables are the most complex part of the AnyEvent API, here are
505	optionally wait for them. They can also be called merge points - points	579	some different mental models of what they are - pick the ones you can connect to:
506	in time where multiple outstanding events have been processed. And yet	580
507	another way to call them is transactions - each condition variable can be	581	=over 4
508	used to represent a transaction, which finishes at some point and delivers	582
509	a result.	583	=item * Condition variables are like callbacks - you can call them (and pass them instead
		584	of callbacks). Unlike callbacks however, you can also wait for them to be called.
		585
		586	=item * Condition variables are signals - one side can emit or send them,
		587	the other side can wait for them, or install a handler that is called when
		588	the signal fires.
		589
		590	=item * Condition variables are like "Merge Points" - points in your program
		591	where you merge multiple independent results/control flows into one.
		592
		593	=item * Condition variables represent a transaction - function that start
		594	some kind of transaction can return them, leaving the caller the choice
		595	between waiting in a blocking fashion, or setting a callback.
		596
		597	=item * Condition variables represent future values, or promises to deliver
		598	some result, long before the result is available.
		599
		600	=back
510		601
511	Condition variables are very useful to signal that something has finished,	602	Condition variables are very useful to signal that something has finished,
512	for example, if you write a module that does asynchronous http requests,	603	for example, if you write a module that does asynchronous http requests,
513	then a condition variable would be the ideal candidate to signal the	604	then a condition variable would be the ideal candidate to signal the
514	availability of results. The user can either act when the callback is	605	availability of results. The user can either act when the callback is
…		…
535	eventually calls C<< -> send >>, and the "consumer side", which waits	626	eventually calls C<< -> send >>, and the "consumer side", which waits
536	for the send to occur.	627	for the send to occur.
537		628
538	Example: wait for a timer.	629	Example: wait for a timer.
539		630
540	# wait till the result is ready	631	# condition: "wait till the timer is fired"
541	my $result_ready = AnyEvent->condvar;	632	my $timer_fired = AnyEvent->condvar;
542		633
543	# do something such as adding a timer	634	# create the timer - we could wait for, say
544	# or socket watcher the calls $result_ready->send	635	# a handle becomign ready, or even an
545	# when the "result" is ready.	636	# AnyEvent::HTTP request to finish, but
546	# in this case, we simply use a timer:	637	# in this case, we simply use a timer:
547	my $w = AnyEvent->timer (	638	my $w = AnyEvent->timer (
548	after => 1,	639	after => 1,
549	cb => sub { $result_ready->send },	640	cb => sub { $timer_fired->send },
550	);	641	);
551		642
552	# this "blocks" (while handling events) till the callback	643	# this "blocks" (while handling events) till the callback
553	# calls -<send	644	# calls ->send
554	$result_ready->recv;	645	$timer_fired->recv;
555		646
556	Example: wait for a timer, but take advantage of the fact that condition	647	Example: wait for a timer, but take advantage of the fact that condition
557	variables are also callable directly.	648	variables are also callable directly.
558		649
559	my $done = AnyEvent->condvar;	650	my $done = AnyEvent->condvar;
…		…
622	one. For example, a function that pings many hosts in parallel might want	713	one. For example, a function that pings many hosts in parallel might want
623	to use a condition variable for the whole process.	714	to use a condition variable for the whole process.
624		715
625	Every call to C<< ->begin >> will increment a counter, and every call to	716	Every call to C<< ->begin >> will increment a counter, and every call to
626	C<< ->end >> will decrement it. If the counter reaches C<0> in C<< ->end	717	C<< ->end >> will decrement it. If the counter reaches C<0> in C<< ->end
627	>>, the (last) callback passed to C<begin> will be executed. That callback	718	>>, the (last) callback passed to C<begin> will be executed, passing the
628	is I<supposed> to call C<< ->send >>, but that is not required. If no	719	condvar as first argument. That callback is I<supposed> to call C<< ->send
629	callback was set, C<send> will be called without any arguments.	720	>>, but that is not required. If no group callback was set, C<send> will
		721	be called without any arguments.
630		722
631	You can think of C<< $cv->send >> giving you an OR condition (one call	723	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	724	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).	725	condition (all C<begin> calls must be C<end>'ed before the condvar sends).
634		726
…		…
661	begung can potentially be zero:	753	begung can potentially be zero:
662		754
663	my $cv = AnyEvent->condvar;	755	my $cv = AnyEvent->condvar;
664		756
665	my %result;	757	my %result;
666	$cv->begin (sub { $cv->send (\%result) });	758	$cv->begin (sub { shift->send (\%result) });
667		759
668	for my $host (@list_of_hosts) {	760	for my $host (@list_of_hosts) {
669	$cv->begin;	761	$cv->begin;
670	ping_host_then_call_callback $host, sub {	762	ping_host_then_call_callback $host, sub {
671	$result{$host} = ...;	763	$result{$host} = ...;
…		…
746	=item $cb = $cv->cb ($cb->($cv))	838	=item $cb = $cv->cb ($cb->($cv))
747		839
748	This is a mutator function that returns the callback set and optionally	840	This is a mutator function that returns the callback set and optionally
749	replaces it before doing so.	841	replaces it before doing so.
750		842
751	The callback will be called when the condition becomes "true", i.e. when	843	The callback will be called when the condition becomes (or already was)
752	C<send> or C<croak> are called, with the only argument being the condition	844	"true", i.e. when C<send> or C<croak> are called (or were called), with
753	variable itself. Calling C<recv> inside the callback or at any later time	845	the only argument being the condition variable itself. Calling C<recv>
754	is guaranteed not to block.	846	inside the callback or at any later time is guaranteed not to block.
755		847
756	=back	848	=back
757		849
758	=head1 SUPPORTED EVENT LOOPS/BACKENDS	850	=head1 SUPPORTED EVENT LOOPS/BACKENDS
759		851
…		…
762	=over 4	854	=over 4
763		855
764	=item Backends that are autoprobed when no other event loop can be found.	856	=item Backends that are autoprobed when no other event loop can be found.
765		857
766	EV is the preferred backend when no other event loop seems to be in	858	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	859	use. If EV is not installed, then AnyEvent will fall back to its own
768	that, will fall back to its own pure-perl implementation, which is	860	pure-perl implementation, which is available everywhere as it comes with
769	available everywhere as it comes with AnyEvent itself.	861	AnyEvent itself.
770		862
771	AnyEvent::Impl::EV based on EV (interface to libev, best choice).	863	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.	864	AnyEvent::Impl::Perl pure-perl implementation, fast and portable.
774		865
775	=item Backends that are transparently being picked up when they are used.	866	=item Backends that are transparently being picked up when they are used.
776		867
777	These will be used when they are currently loaded when the first watcher	868	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	869	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	870	them. This means that AnyEvent will automatically pick the right backend
780	when the main program loads an event module before anything starts to	871	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.	872	create watchers. Nothing special needs to be done by the main program.
782		873
		874	AnyEvent::Impl::Event based on Event, very stable, few glitches.
783	AnyEvent::Impl::Glib based on Glib, slow but very stable.	875	AnyEvent::Impl::Glib based on Glib, slow but very stable.
784	AnyEvent::Impl::Tk based on Tk, very broken.	876	AnyEvent::Impl::Tk based on Tk, very broken.
785	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.	877	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
786	AnyEvent::Impl::POE based on POE, very slow, some limitations.	878	AnyEvent::Impl::POE based on POE, very slow, some limitations.
		879	AnyEvent::Impl::Irssi used when running within irssi.
787		880
788	=item Backends with special needs.	881	=item Backends with special needs.
789		882
790	Qt requires the Qt::Application to be instantiated first, but will	883	Qt requires the Qt::Application to be instantiated first, but will
791	otherwise be picked up automatically. As long as the main program	884	otherwise be picked up automatically. As long as the main program
…		…
865	event module detection too early, for example, L<AnyEvent::AIO> creates	958	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	959	and installs the global L<IO::AIO> watcher in a C<post_detect> block to
867	avoid autodetecting the event module at load time.	960	avoid autodetecting the event module at load time.
868		961
869	If called in scalar or list context, then it creates and returns an object	962	If called in scalar or list context, then it creates and returns an object
870	that automatically removes the callback again when it is destroyed. See	963	that automatically removes the callback again when it is destroyed (or
		964	C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for
871	L<Coro::BDB> for a case where this is useful.	965	a case where this is useful.
		966
		967	Example: Create a watcher for the IO::AIO module and store it in
		968	C<$WATCHER>. Only do so after the event loop is initialised, though.
		969
		970	our WATCHER;
		971
		972	my $guard = AnyEvent::post_detect {
		973	$WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb);
		974	};
		975
		976	# the \|\|= is important in case post_detect immediately runs the block,
		977	# as to not clobber the newly-created watcher. assigning both watcher and
		978	# post_detect guard to the same variable has the advantage of users being
		979	# able to just C<undef $WATCHER> if the watcher causes them grief.
		980
		981	$WATCHER \|\|= $guard;
872		982
873	=item @AnyEvent::post_detect	983	=item @AnyEvent::post_detect
874		984
875	If there are any code references in this array (you can C<push> to it	985	If there are any code references in this array (you can C<push> to it
876	before or after loading AnyEvent), then they will called directly after	986	before or after loading AnyEvent), then they will called directly after
…		…
879	You should check C<$AnyEvent::MODEL> before adding to this array, though:	989	You should check C<$AnyEvent::MODEL> before adding to this array, though:
880	if it is defined then the event loop has already been detected, and the	990	if it is defined then the event loop has already been detected, and the
881	array will be ignored.	991	array will be ignored.
882		992
883	Best use C<AnyEvent::post_detect { BLOCK }> when your application allows	993	Best use C<AnyEvent::post_detect { BLOCK }> when your application allows
884	it,as it takes care of these details.	994	it, as it takes care of these details.
885		995
886	This variable is mainly useful for modules that can do something useful	996	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	997	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	998	not need to even load it by default. This array provides the means to hook
889	into AnyEvent passively, without loading it.	999	into AnyEvent passively, without loading it.
		1000
		1001	Example: To load Coro::AnyEvent whenever Coro and AnyEvent are used
		1002	together, you could put this into Coro (this is the actual code used by
		1003	Coro to accomplish this):
		1004
		1005	if (defined $AnyEvent::MODEL) {
		1006	# AnyEvent already initialised, so load Coro::AnyEvent
		1007	require Coro::AnyEvent;
		1008	} else {
		1009	# AnyEvent not yet initialised, so make sure to load Coro::AnyEvent
		1010	# as soon as it is
		1011	push @AnyEvent::post_detect, sub { require Coro::AnyEvent };
		1012	}
890		1013
891	=back	1014	=back
892		1015
893	=head1 WHAT TO DO IN A MODULE	1016	=head1 WHAT TO DO IN A MODULE
894		1017
…		…
951	=head1 OTHER MODULES	1074	=head1 OTHER MODULES
952		1075
953	The following is a non-exhaustive list of additional modules that use	1076	The following is a non-exhaustive list of additional modules that use
954	AnyEvent as a client and can therefore be mixed easily with other AnyEvent	1077	AnyEvent as a client and can therefore be mixed easily with other AnyEvent
955	modules and other event loops in the same program. Some of the modules	1078	modules and other event loops in the same program. Some of the modules
956	come with AnyEvent, most are available via CPAN.	1079	come as part of AnyEvent, the others are available via CPAN.
957		1080
958	=over 4	1081	=over 4
959		1082
960	=item L<AnyEvent::Util>	1083	=item L<AnyEvent::Util>
961		1084
…		…
976		1099
977	=item L<AnyEvent::DNS>	1100	=item L<AnyEvent::DNS>
978		1101
979	Provides rich asynchronous DNS resolver capabilities.	1102	Provides rich asynchronous DNS resolver capabilities.
980		1103
		1104	=item L<AnyEvent::HTTP>, L<AnyEvent::IRC>, L<AnyEvent::XMPP>, L<AnyEvent::GPSD>, L<AnyEvent::IGS>, L<AnyEvent::FCP>
		1105
		1106	Implement event-based interfaces to the protocols of the same name (for
		1107	the curious, IGS is the International Go Server and FCP is the Freenet
		1108	Client Protocol).
		1109
		1110	=item L<AnyEvent::Handle::UDP>
		1111
		1112	Here be danger!
		1113
		1114	As Pauli would put it, "Not only is it not right, it's not even wrong!" -
		1115	there are so many things wrong with AnyEvent::Handle::UDP, most notably
		1116	it's use of a stream-based API with a protocol that isn't streamable, that
		1117	the only way to improve it is to delete it.
		1118
		1119	It features data corruption (but typically only under load) and general
		1120	confusion. On top, the author is not only clueless about UDP but also
		1121	fact-resistant - some gems of his understanding: "connect doesn't work
		1122	with UDP", "UDP packets are not IP packets", "UDP only has datagrams, not
		1123	packets", "I don't need to implement proper error checking as UDP doesn't
		1124	support error checking" and so on - he doesn't even understand what's
		1125	wrong with his module when it is explained to him.
		1126
981	=item L<AnyEvent::HTTP>	1127	=item L<AnyEvent::DBI>
982		1128
983	A simple-to-use HTTP library that is capable of making a lot of concurrent	1129	Executes L<DBI> requests asynchronously in a proxy process for you,
984	HTTP requests.	1130	notifying you in an event-bnased way when the operation is finished.
		1131
		1132	=item L<AnyEvent::AIO>
		1133
		1134	Truly asynchronous (as opposed to non-blocking) I/O, should be in the
		1135	toolbox of every event programmer. AnyEvent::AIO transparently fuses
		1136	L<IO::AIO> and AnyEvent together, giving AnyEvent access to event-based
		1137	file I/O, and much more.
985		1138
986	=item L<AnyEvent::HTTPD>	1139	=item L<AnyEvent::HTTPD>
987		1140
988	Provides a simple web application server framework.	1141	A simple embedded webserver.
989		1142
990	=item L<AnyEvent::FastPing>	1143	=item L<AnyEvent::FastPing>
991		1144
992	The fastest ping in the west.	1145	The fastest ping in the west.
993
994	=item L<AnyEvent::DBI>
995
996	Executes L<DBI> requests asynchronously in a proxy process.
997
998	=item L<AnyEvent::AIO>
999
1000	Truly asynchronous I/O, should be in the toolbox of every event
1001	programmer. AnyEvent::AIO transparently fuses L<IO::AIO> and AnyEvent
1002	together.
1003
1004	=item L<AnyEvent::BDB>
1005
1006	Truly asynchronous Berkeley DB access. AnyEvent::BDB transparently fuses
1007	L<BDB> and AnyEvent together.
1008
1009	=item L<AnyEvent::GPSD>
1010
1011	A non-blocking interface to gpsd, a daemon delivering GPS information.
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
1022	=item L<AnyEvent::IGS>
1023
1024	A non-blocking interface to the Internet Go Server protocol (used by
1025	L<App::IGS>).
1026
1027	=item L<Net::FCP>
1028
1029	AnyEvent-based implementation of the Freenet Client Protocol, birthplace
1030	of AnyEvent.
1031
1032	=item L<Event::ExecFlow>
1033
1034	High level API for event-based execution flow control.
1035		1146
1036	=item L<Coro>	1147	=item L<Coro>
1037		1148
1038	Has special support for AnyEvent via L<Coro::AnyEvent>.	1149	Has special support for AnyEvent via L<Coro::AnyEvent>.
1039		1150
…		…
1043		1154
1044	package AnyEvent;	1155	package AnyEvent;
1045		1156
1046	# basically a tuned-down version of common::sense	1157	# basically a tuned-down version of common::sense
1047	sub common_sense {	1158	sub common_sense {
1048	# no warnings	1159	# from common:.sense 1.0
1049	${^WARNING_BITS} ^= ${^WARNING_BITS};	1160	${^WARNING_BITS} = "\xfc\x3f\x33\x00\x0f\xf3\xcf\xc0\xf3\xfc\x33\x00";
1050	# use strict vars subs	1161	# use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl)
1051	$^H \|= 0x00000600;	1162	$^H \|= 0x00000600;
1052	}	1163	}
1053		1164
1054	BEGIN { AnyEvent::common_sense }	1165	BEGIN { AnyEvent::common_sense }
1055		1166
1056	use Carp ();	1167	use Carp ();
1057		1168
1058	our $VERSION = 4.83;	1169	our $VERSION = '5.271';
1059	our $MODEL;	1170	our $MODEL;
1060		1171
1061	our $AUTOLOAD;	1172	our $AUTOLOAD;
1062	our @ISA;	1173	our @ISA;
1063		1174
1064	our @REGISTRY;	1175	our @REGISTRY;
1065		1176
1066	our $WIN32;
1067
1068	our $VERBOSE;	1177	our $VERBOSE;
1069		1178
1070	BEGIN {	1179	BEGIN {
1071	eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }";	1180	require "AnyEvent/constants.pl";
		1181
1072	eval "sub TAINT(){ " . (${^TAINT}*1) . " }";	1182	eval "sub TAINT (){" . (${^TAINT}*1) . "}";
1073		1183
1074	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}	1184	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}
1075	if ${^TAINT};	1185	if ${^TAINT};
1076		1186
1077	$VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1;	1187	$VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1;
…		…
1088	for reverse split /\s,\s/,	1198	for reverse split /\s,\s/,
1089	$ENV{PERL_ANYEVENT_PROTOCOLS} \|\| "ipv4,ipv6";	1199	$ENV{PERL_ANYEVENT_PROTOCOLS} \|\| "ipv4,ipv6";
1090	}	1200	}
1091		1201
1092	my @models = (	1202	my @models = (
1093	[EV:: => AnyEvent::Impl::EV::],	1203	[EV:: => AnyEvent::Impl::EV:: , 1],
1094	[Event:: => AnyEvent::Impl::Event::],
1095	[AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::],	1204	[AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl:: , 1],
1096	# everything below here will not be autoprobed	1205	# everything below here will not (normally) be autoprobed
1097	# as the pureperl backend should work everywhere	1206	# as the pureperl backend should work everywhere
1098	# and is usually faster	1207	# and is usually faster
		1208	[Event:: => AnyEvent::Impl::Event::, 1],
1099	[Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers	1209	[Glib:: => AnyEvent::Impl::Glib:: , 1], # becomes extremely slow with many watchers
1100	[Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy	1210	[Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
		1211	[Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package
1101	[Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles	1212	[Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
1102	[Qt:: => AnyEvent::Impl::Qt::], # requires special main program	1213	[Qt:: => AnyEvent::Impl::Qt::], # requires special main program
1103	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza	1214	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
1104	[Wx:: => AnyEvent::Impl::POE::],	1215	[Wx:: => AnyEvent::Impl::POE::],
1105	[Prima:: => AnyEvent::Impl::POE::],	1216	[Prima:: => AnyEvent::Impl::POE::],
1106	# IO::Async is just too broken - we would need workarounds for its	1217	# IO::Async is just too broken - we would need workarounds for its
1107	# byzantine signal and broken child handling, among others.	1218	# byzantine signal and broken child handling, among others.
1108	# IO::Async is rather hard to detect, as it doesn't have any	1219	# IO::Async is rather hard to detect, as it doesn't have any
1109	# obvious default class.	1220	# obvious default class.
1110	# [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program	1221	[IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program
1111	# [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program	1222	[IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program
1112	# [IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program	1223	[IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program
		1224	[AnyEvent::Impl::IOAsync:: => AnyEvent::Impl::IOAsync::], # requires special main program
1113	);	1225	);
1114		1226
1115	our %method = map +($_ => 1),	1227	our %method = map +($_ => 1),
1116	qw(io timer time now now_update signal child idle condvar one_event DESTROY);	1228	qw(io timer time now now_update signal child idle condvar one_event DESTROY);
1117		1229
1118	our @post_detect;	1230	our @post_detect;
1119		1231
1120	sub post_detect(&) {	1232	sub post_detect(&) {
1121	my ($cb) = @_;	1233	my ($cb) = @_;
1122		1234
1123	if ($MODEL) {
1124	$cb->();
1125
1126	1
1127	} else {
1128	push @post_detect, $cb;	1235	push @post_detect, $cb;
1129		1236
1130	defined wantarray	1237	defined wantarray
1131	? bless \$cb, "AnyEvent::Util::postdetect"	1238	? bless \$cb, "AnyEvent::Util::postdetect"
1132	: ()	1239	: ()
1133	}
1134	}	1240	}
1135		1241
1136	sub AnyEvent::Util::postdetect::DESTROY {	1242	sub AnyEvent::Util::postdetect::DESTROY {
1137	@post_detect = grep $_ != ${$_[0]}, @post_detect;	1243	@post_detect = grep $_ != ${$_[0]}, @post_detect;
1138	}	1244	}
1139		1245
1140	sub detect() {	1246	sub detect() {
		1247	# free some memory
		1248	*detect = sub () { $MODEL };
		1249
		1250	local $!; # for good measure
		1251	local $SIG{__DIE__};
		1252
		1253	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {
		1254	my $model = "AnyEvent::Impl::$1";
		1255	if (eval "require $model") {
		1256	$MODEL = $model;
		1257	warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2;
		1258	} else {
		1259	warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE;
		1260	}
		1261	}
		1262
		1263	# check for already loaded models
1141	unless ($MODEL) {	1264	unless ($MODEL) {
1142	local $SIG{__DIE__};	1265	for (@REGISTRY, @models) {
1143		1266	my ($package, $model) = @$_;
1144	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {	1267	if (${"$package\::VERSION"} > 0) {
1145	my $model = "AnyEvent::Impl::$1";
1146	if (eval "require $model") {	1268	if (eval "require $model") {
1147	$MODEL = $model;	1269	$MODEL = $model;
1148	warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2;	1270	warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2;
1149	} else {	1271	last;
1150	warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE;	1272	}
1151	}	1273	}
1152	}	1274	}
1153		1275
1154	# check for already loaded models
1155	unless ($MODEL) {	1276	unless ($MODEL) {
		1277	# try to autoload a model
1156	for (@REGISTRY, @models) {	1278	for (@REGISTRY, @models) {
1157	my ($package, $model) = @$_;	1279	my ($package, $model, $autoload) = @$_;
		1280	if (
		1281	$autoload
		1282	and eval "require $package"
1158	if (${"$package\::VERSION"} > 0) {	1283	and ${"$package\::VERSION"} > 0
1159	if (eval "require $model") {	1284	and eval "require $model"
		1285	) {
1160	$MODEL = $model;	1286	$MODEL = $model;
1161	warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2;	1287	warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2;
1162	last;	1288	last;
1163	}
1164	}	1289	}
1165	}	1290	}
1166		1291
1167	unless ($MODEL) {
1168	# try to load a model
1169
1170	for (@REGISTRY, @models) {
1171	my ($package, $model) = @$_;
1172	if (eval "require $package"
1173	and ${"$package\::VERSION"} > 0
1174	and eval "require $model") {
1175	$MODEL = $model;
1176	warn "AnyEvent: autoprobed model '$model', using it.\n" if $VERBOSE >= 2;
1177	last;
1178	}
1179	}
1180
1181	$MODEL	1292	$MODEL
1182	or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.\n";	1293	or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.\n";
1183	}
1184	}	1294	}
1185
1186	push @{"$MODEL\::ISA"}, "AnyEvent::Base";
1187
1188	unshift @ISA, $MODEL;
1189
1190	require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT};
1191
1192	(shift @post_detect)->() while @post_detect;
1193	}	1295	}
		1296
		1297	@models = (); # free probe data
		1298
		1299	push @{"$MODEL\::ISA"}, "AnyEvent::Base";
		1300	unshift @ISA, $MODEL;
		1301
		1302	# now nuke some methods that are overriden by the backend.
		1303	# SUPER is not allowed.
		1304	for (qw(time signal child idle)) {
		1305	undef &{"AnyEvent::Base::$_"}
		1306	if defined &{"$MODEL\::$_"};
		1307	}
		1308
		1309	require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT};
		1310
		1311	(shift @post_detect)->() while @post_detect;
		1312
		1313	*post_detect = sub(&) {
		1314	shift->();
		1315
		1316	undef
		1317	};
1194		1318
1195	$MODEL	1319	$MODEL
1196	}	1320	}
1197		1321
1198	sub AUTOLOAD {	1322	sub AUTOLOAD {
1199	(my $func = $AUTOLOAD) =~ s/.*://;	1323	(my $func = $AUTOLOAD) =~ s/.*://;
1200		1324
1201	$method{$func}	1325	$method{$func}
1202	or Carp::croak "$func: not a valid method for AnyEvent objects";	1326	or Carp::croak "$func: not a valid AnyEvent class method";
1203		1327
1204	detect unless $MODEL;	1328	detect;
1205		1329
1206	my $class = shift;	1330	my $class = shift;
1207	$class->$func (@_);	1331	$class->$func (@_);
1208	}	1332	}
1209		1333
…		…
1222	# we assume CLOEXEC is already set by perl in all important cases	1346	# we assume CLOEXEC is already set by perl in all important cases
1223		1347
1224	($fh2, $rw)	1348	($fh2, $rw)
1225	}	1349	}
1226		1350
		1351	=head1 SIMPLIFIED AE API
		1352
		1353	Starting with version 5.0, AnyEvent officially supports a second, much
		1354	simpler, API that is designed to reduce the calling, typing and memory
		1355	overhead by using function call syntax and a fixed number of parameters.
		1356
		1357	See the L<AE> manpage for details.
		1358
		1359	=cut
		1360
		1361	package AE;
		1362
		1363	our $VERSION = $AnyEvent::VERSION;
		1364
		1365	# fall back to the main API by default - backends and AnyEvent::Base
		1366	# implementations can overwrite these.
		1367
		1368	sub io($$$) {
		1369	AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])
		1370	}
		1371
		1372	sub timer($$$) {
		1373	AnyEvent->timer (after => $_[0], interval => $_[1], cb => $_[2])
		1374	}
		1375
		1376	sub signal($$) {
		1377	AnyEvent->signal (signal => $_[0], cb => $_[1])
		1378	}
		1379
		1380	sub child($$) {
		1381	AnyEvent->child (pid => $_[0], cb => $_[1])
		1382	}
		1383
		1384	sub idle($) {
		1385	AnyEvent->idle (cb => $_[0])
		1386	}
		1387
		1388	sub cv(;&) {
		1389	AnyEvent->condvar (@_ ? (cb => $_[0]) : ())
		1390	}
		1391
		1392	sub now() {
		1393	AnyEvent->now
		1394	}
		1395
		1396	sub now_update() {
		1397	AnyEvent->now_update
		1398	}
		1399
		1400	sub time() {
		1401	AnyEvent->time
		1402	}
		1403
1227	package AnyEvent::Base;	1404	package AnyEvent::Base;
1228		1405
1229	# default implementations for many methods	1406	# default implementations for many methods
1230		1407
1231	sub _time {	1408	sub time {
		1409	eval q{ # poor man's autoloading {}
1232	# probe for availability of Time::HiRes	1410	# probe for availability of Time::HiRes
1233	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {	1411	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
1234	warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8;	1412	warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8;
1235	*_time = \&Time::HiRes::time;	1413	*AE::time = \&Time::HiRes::time;
1236	# if (eval "use POSIX (); (POSIX::times())...	1414	# if (eval "use POSIX (); (POSIX::times())...
1237	} else {	1415	} else {
1238	warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE;	1416	warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE;
1239	*_time = sub { time }; # epic fail	1417	*AE::time = sub (){ time }; # epic fail
		1418	}
		1419
		1420	*time = sub { AE::time }; # different prototypes
1240	}	1421	};
		1422	die if $@;
1241		1423
1242	&_time	1424	&time
1243	}	1425	}
1244		1426
1245	sub time { _time }	1427	*now = \&time;
1246	sub now { _time }	1428
1247	sub now_update { }	1429	sub now_update { }
1248		1430
1249	# default implementation for ->condvar	1431	# default implementation for ->condvar
1250		1432
1251	sub condvar {	1433	sub condvar {
		1434	eval q{ # poor man's autoloading {}
		1435	*condvar = sub {
1252	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"	1436	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"
		1437	};
		1438
		1439	*AE::cv = sub (;&) {
		1440	bless { @_ ? (_ae_cb => shift) : () }, "AnyEvent::CondVar"
		1441	};
		1442	};
		1443	die if $@;
		1444
		1445	&condvar
1253	}	1446	}
1254		1447
1255	# default implementation for ->signal	1448	# default implementation for ->signal
1256		1449
1257	our $HAVE_ASYNC_INTERRUPT;	1450	our $HAVE_ASYNC_INTERRUPT;
		1451
		1452	sub _have_async_interrupt() {
		1453	$HAVE_ASYNC_INTERRUPT = 1*(!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT}
		1454	&& eval "use Async::Interrupt 1.02 (); 1")
		1455	unless defined $HAVE_ASYNC_INTERRUPT;
		1456
		1457	$HAVE_ASYNC_INTERRUPT
		1458	}
		1459
1258	our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);	1460	our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);
1259	our (%SIG_ASY, %SIG_ASY_W);	1461	our (%SIG_ASY, %SIG_ASY_W);
1260	our ($SIG_COUNT, $SIG_TW);	1462	our ($SIG_COUNT, $SIG_TW);
1261		1463
1262	sub _signal_exec {	1464	# install a dummy wakeup watcher to reduce signal catching latency
1263	$HAVE_ASYNC_INTERRUPT	1465	# used by Impls
1264	? $SIGPIPE_R->drain	1466	sub _sig_add() {
1265	: sysread $SIGPIPE_R, my $dummy, 9;	1467	unless ($SIG_COUNT++) {
		1468	# try to align timer on a full-second boundary, if possible
		1469	my $NOW = AE::now;
1266		1470
1267	while (%SIG_EV) {	1471	$SIG_TW = AE::timer
1268	for (keys %SIG_EV) {	1472	$MAX_SIGNAL_LATENCY - ($NOW - int $NOW),
1269	delete $SIG_EV{$_};	1473	$MAX_SIGNAL_LATENCY,
1270	$_->() for values %{ $SIG_CB{$_} \|\| {} };	1474	sub { } # just for the PERL_ASYNC_CHECK
1271	}	1475	;
1272	}	1476	}
1273	}	1477	}
1274		1478
1275	sub _signal {	1479	sub _sig_del {
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, $arg{cb}], "AnyEvent::Base::signal"
1317	}
1318
1319	sub signal {
1320	# probe for availability of Async::Interrupt
1321	if (!$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;
1323
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 $VERBOSE >= 8;
1330
1331	require Fcntl;
1332
1333	if (AnyEvent::WIN32) {
1334	require AnyEvent::Util;
1335
1336	($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
1337	AnyEvent::Util::fh_nonblocking ($SIGPIPE_R) if $SIGPIPE_R;
1338	AnyEvent::Util::fh_nonblocking ($SIGPIPE_W) if $SIGPIPE_W; # just in case
1339	} else {
1340	pipe $SIGPIPE_R, $SIGPIPE_W;
1341	fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R;
1342	fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case
1343
1344	# not strictly required, as $^F is normally 2, but let's make sure...
1345	fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
1346	fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
1347	}
1348
1349	$SIGPIPE_R
1350	or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1351
1352	$SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec);
1353	}
1354
1355	*signal = \&_signal;
1356	&signal
1357	}
1358
1359	sub AnyEvent::Base::signal::DESTROY {
1360	my ($signal, $cb) = @{$_[0]};
1361
1362	undef $SIG_TW	1480	undef $SIG_TW
1363	unless --$SIG_COUNT;	1481	unless --$SIG_COUNT;
		1482	}
1364		1483
		1484	our $_sig_name_init; $_sig_name_init = sub {
		1485	eval q{ # poor man's autoloading {}
		1486	undef $_sig_name_init;
		1487
		1488	if (_have_async_interrupt) {
		1489	*sig2num = \&Async::Interrupt::sig2num;
		1490	*sig2name = \&Async::Interrupt::sig2name;
		1491	} else {
		1492	require Config;
		1493
		1494	my %signame2num;
		1495	@signame2num{ split ' ', $Config::Config{sig_name} }
		1496	= split ' ', $Config::Config{sig_num};
		1497
		1498	my @signum2name;
		1499	@signum2name[values %signame2num] = keys %signame2num;
		1500
		1501	*sig2num = sub($) {
		1502	$_[0] > 0 ? shift : $signame2num{+shift}
		1503	};
		1504	*sig2name = sub ($) {
		1505	$_[0] > 0 ? $signum2name[+shift] : shift
		1506	};
		1507	}
		1508	};
		1509	die if $@;
		1510	};
		1511
		1512	sub sig2num ($) { &$_sig_name_init; &sig2num }
		1513	sub sig2name($) { &$_sig_name_init; &sig2name }
		1514
		1515	sub signal {
		1516	eval q{ # poor man's autoloading {}
		1517	# probe for availability of Async::Interrupt
		1518	if (_have_async_interrupt) {
		1519	warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8;
		1520
		1521	$SIGPIPE_R = new Async::Interrupt::EventPipe;
		1522	$SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;
		1523
		1524	} else {
		1525	warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;
		1526
		1527	if (AnyEvent::WIN32) {
		1528	require AnyEvent::Util;
		1529
		1530	($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
		1531	AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R;
		1532	AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case
		1533	} else {
		1534	pipe $SIGPIPE_R, $SIGPIPE_W;
		1535	fcntl $SIGPIPE_R, AnyEvent::F_SETFL, AnyEvent::O_NONBLOCK if $SIGPIPE_R;
		1536	fcntl $SIGPIPE_W, AnyEvent::F_SETFL, AnyEvent::O_NONBLOCK if $SIGPIPE_W; # just in case
		1537
		1538	# not strictly required, as $^F is normally 2, but let's make sure...
		1539	fcntl $SIGPIPE_R, AnyEvent::F_SETFD, AnyEvent::FD_CLOEXEC;
		1540	fcntl $SIGPIPE_W, AnyEvent::F_SETFD, AnyEvent::FD_CLOEXEC;
		1541	}
		1542
		1543	$SIGPIPE_R
		1544	or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
		1545
		1546	$SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec;
		1547	}
		1548
		1549	*signal = $HAVE_ASYNC_INTERRUPT
		1550	? sub {
		1551	my (undef, %arg) = @_;
		1552
		1553	# async::interrupt
		1554	my $signal = sig2num $arg{signal};
		1555	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};
		1556
		1557	$SIG_ASY{$signal} \|\|= new Async::Interrupt
		1558	cb => sub { undef $SIG_EV{$signal} },
		1559	signal => $signal,
		1560	pipe => [$SIGPIPE_R->filenos],
		1561	pipe_autodrain => 0,
		1562	;
		1563
		1564	bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
		1565	}
		1566	: sub {
		1567	my (undef, %arg) = @_;
		1568
		1569	# pure perl
		1570	my $signal = sig2name $arg{signal};
		1571	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};
		1572
		1573	$SIG{$signal} \|\|= sub {
		1574	local $!;
		1575	syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
		1576	undef $SIG_EV{$signal};
		1577	};
		1578
		1579	# can't do signal processing without introducing races in pure perl,
		1580	# so limit the signal latency.
		1581	_sig_add;
		1582
		1583	bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
		1584	}
		1585	;
		1586
		1587	*AnyEvent::Base::signal::DESTROY = sub {
		1588	my ($signal, $cb) = @{$_[0]};
		1589
		1590	_sig_del;
		1591
1365	delete $SIG_CB{$signal}{$cb};	1592	delete $SIG_CB{$signal}{$cb};
1366		1593
		1594	$HAVE_ASYNC_INTERRUPT
		1595	? delete $SIG_ASY{$signal}
1367	# delete doesn't work with older perls - they then	1596	: # delete doesn't work with older perls - they then
1368	# print weird messages, or just unconditionally exit	1597	# print weird messages, or just unconditionally exit
1369	# instead of getting the default action.	1598	# instead of getting the default action.
1370	undef $SIG{$signal}	1599	undef $SIG{$signal}
1371	unless keys %{ $SIG_CB{$signal} };	1600	unless keys %{ $SIG_CB{$signal} };
		1601	};
		1602
		1603	*_signal_exec = sub {
		1604	$HAVE_ASYNC_INTERRUPT
		1605	? $SIGPIPE_R->drain
		1606	: sysread $SIGPIPE_R, (my $dummy), 9;
		1607
		1608	while (%SIG_EV) {
		1609	for (keys %SIG_EV) {
		1610	delete $SIG_EV{$_};
		1611	$_->() for values %{ $SIG_CB{$_} \|\| {} };
		1612	}
		1613	}
		1614	};
		1615	};
		1616	die if $@;
		1617
		1618	&signal
1372	}	1619	}
1373		1620
1374	# default implementation for ->child	1621	# default implementation for ->child
1375		1622
1376	our %PID_CB;	1623	our %PID_CB;
1377	our $CHLD_W;	1624	our $CHLD_W;
1378	our $CHLD_DELAY_W;	1625	our $CHLD_DELAY_W;
1379	our $WNOHANG;	1626	our $WNOHANG;
1380		1627
1381	sub _sigchld {	1628	# used by many Impl's
1382	while (0 < (my $pid = waitpid -1, $WNOHANG)) {	1629	sub _emit_childstatus($$) {
1383	$_->($pid, $?)	1630	my (undef, $rpid, $rstatus) = @_;
		1631
		1632	$_->($rpid, $rstatus)
1384	for values %{ $PID_CB{$pid} \|\| {} },	1633	for values %{ $PID_CB{$rpid} \|\| {} },
1385	values %{ $PID_CB{0} \|\| {} };	1634	values %{ $PID_CB{0} \|\| {} };
1386	}
1387	}	1635	}
1388		1636
1389	sub child {	1637	sub child {
		1638	eval q{ # poor man's autoloading {}
		1639	*_sigchld = sub {
		1640	my $pid;
		1641
		1642	AnyEvent->_emit_childstatus ($pid, $?)
		1643	while ($pid = waitpid -1, $WNOHANG) > 0;
		1644	};
		1645
		1646	*child = sub {
1390	my (undef, %arg) = @_;	1647	my (undef, %arg) = @_;
1391		1648
1392	defined (my $pid = $arg{pid} + 0)	1649	defined (my $pid = $arg{pid} + 0)
1393	or Carp::croak "required option 'pid' is missing";	1650	or Carp::croak "required option 'pid' is missing";
1394		1651
1395	$PID_CB{$pid}{$arg{cb}} = $arg{cb};	1652	$PID_CB{$pid}{$arg{cb}} = $arg{cb};
1396		1653
1397	# WNOHANG is almost cetrainly 1 everywhere	1654	# WNOHANG is almost cetrainly 1 everywhere
1398	$WNOHANG \|\|= $^O =~ /^(?:openbsd\|netbsd\|linux\|freebsd\|cygwin\|MSWin32)$/	1655	$WNOHANG \|\|= $^O =~ /^(?:openbsd\|netbsd\|linux\|freebsd\|cygwin\|MSWin32)$/
1399	? 1	1656	? 1
1400	: eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } \|\| 1;	1657	: eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } \|\| 1;
1401		1658
1402	unless ($CHLD_W) {	1659	unless ($CHLD_W) {
1403	$CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld);	1660	$CHLD_W = AE::signal CHLD => \&_sigchld;
1404	# child could be a zombie already, so make at least one round	1661	# child could be a zombie already, so make at least one round
1405	&_sigchld;	1662	&_sigchld;
1406	}	1663	}
1407		1664
1408	bless [$pid, $arg{cb}], "AnyEvent::Base::child"	1665	bless [$pid, $arg{cb}], "AnyEvent::Base::child"
1409	}	1666	};
1410		1667
1411	sub AnyEvent::Base::child::DESTROY {	1668	*AnyEvent::Base::child::DESTROY = sub {
1412	my ($pid, $cb) = @{$_[0]};	1669	my ($pid, $cb) = @{$_[0]};
1413		1670
1414	delete $PID_CB{$pid}{$cb};	1671	delete $PID_CB{$pid}{$cb};
1415	delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };	1672	delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };
1416		1673
1417	undef $CHLD_W unless keys %PID_CB;	1674	undef $CHLD_W unless keys %PID_CB;
		1675	};
		1676	};
		1677	die if $@;
		1678
		1679	&child
1418	}	1680	}
1419		1681
1420	# idle emulation is done by simply using a timer, regardless	1682	# idle emulation is done by simply using a timer, regardless
1421	# of whether the process is idle or not, and not letting	1683	# of whether the process is idle or not, and not letting
1422	# the callback use more than 50% of the time.	1684	# the callback use more than 50% of the time.
1423	sub idle {	1685	sub idle {
		1686	eval q{ # poor man's autoloading {}
		1687	*idle = sub {
1424	my (undef, %arg) = @_;	1688	my (undef, %arg) = @_;
1425		1689
1426	my ($cb, $w, $rcb) = $arg{cb};	1690	my ($cb, $w, $rcb) = $arg{cb};
1427		1691
1428	$rcb = sub {	1692	$rcb = sub {
1429	if ($cb) {	1693	if ($cb) {
1430	$w = _time;	1694	$w = _time;
1431	&$cb;	1695	&$cb;
1432	$w = _time - $w;	1696	$w = _time - $w;
1433		1697
1434	# never use more then 50% of the time for the idle watcher,	1698	# never use more then 50% of the time for the idle watcher,
1435	# within some limits	1699	# within some limits
1436	$w = 0.0001 if $w < 0.0001;	1700	$w = 0.0001 if $w < 0.0001;
1437	$w = 5 if $w > 5;	1701	$w = 5 if $w > 5;
1438		1702
1439	$w = AnyEvent->timer (after => $w, cb => $rcb);	1703	$w = AE::timer $w, 0, $rcb;
1440	} else {	1704	} else {
1441	# clean up...	1705	# clean up...
1442	undef $w;	1706	undef $w;
1443	undef $rcb;	1707	undef $rcb;
		1708	}
		1709	};
		1710
		1711	$w = AE::timer 0.05, 0, $rcb;
		1712
		1713	bless \\$cb, "AnyEvent::Base::idle"
1444	}	1714	};
		1715
		1716	*AnyEvent::Base::idle::DESTROY = sub {
		1717	undef $${$_[0]};
		1718	};
1445	};	1719	};
		1720	die if $@;
1446		1721
1447	$w = AnyEvent->timer (after => 0.05, cb => $rcb);	1722	&idle
1448
1449	bless \\$cb, "AnyEvent::Base::idle"
1450	}
1451
1452	sub AnyEvent::Base::idle::DESTROY {
1453	undef $${$_[0]};
1454	}	1723	}
1455		1724
1456	package AnyEvent::CondVar;	1725	package AnyEvent::CondVar;
1457		1726
1458	our @ISA = AnyEvent::CondVar::Base::;	1727	our @ISA = AnyEvent::CondVar::Base::;
…		…
1506	Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak};	1775	Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak};
1507	wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0]	1776	wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0]
1508	}	1777	}
1509		1778
1510	sub cb {	1779	sub cb {
1511	$_[0]{_ae_cb} = $_[1] if @_ > 1;	1780	my $cv = shift;
		1781
		1782	@_
		1783	and $cv->{_ae_cb} = shift
		1784	and $cv->{_ae_sent}
		1785	and (delete $cv->{_ae_cb})->($cv);
		1786
1512	$_[0]{_ae_cb}	1787	$cv->{_ae_cb}
1513	}	1788	}
1514		1789
1515	sub begin {	1790	sub begin {
1516	++$_[0]{_ae_counter};	1791	++$_[0]{_ae_counter};
1517	$_[0]{_ae_end_cb} = $_[1] if @_ > 1;	1792	$_[0]{_ae_end_cb} = $_[1] if @_ > 1;
…		…
1726	warn "read: $input\n"; # output what has been read	2001	warn "read: $input\n"; # output what has been read
1727	$cv->send if $input =~ /^q/i; # quit program if /^q/i	2002	$cv->send if $input =~ /^q/i; # quit program if /^q/i
1728	},	2003	},
1729	);	2004	);
1730		2005
1731	my $time_watcher; # can only be used once
1732
1733	sub new_timer {
1734	$timer = AnyEvent->timer (after => 1, cb => sub {	2006	my $time_watcher = AnyEvent->timer (after => 1, interval => 1, cb => sub {
1735	warn "timeout\n"; # print 'timeout' about every second	2007	warn "timeout\n"; # print 'timeout' at most every second
1736	&new_timer; # and restart the time
1737	});	2008	});
1738	}
1739
1740	new_timer; # create first timer
1741		2009
1742	$cv->recv; # wait until user enters /^q/i	2010	$cv->recv; # wait until user enters /^q/i
1743		2011
1744	=head1 REAL-WORLD EXAMPLE	2012	=head1 REAL-WORLD EXAMPLE
1745		2013
…		…
1818		2086
1819	The actual code goes further and collects all errors (C<die>s, exceptions)	2087	The actual code goes further and collects all errors (C<die>s, exceptions)
1820	that occurred during request processing. The C<result> method detects	2088	that occurred during request processing. The C<result> method detects
1821	whether an exception as thrown (it is stored inside the $txn object)	2089	whether an exception as thrown (it is stored inside the $txn object)
1822	and just throws the exception, which means connection errors and other	2090	and just throws the exception, which means connection errors and other
1823	problems get reported tot he code that tries to use the result, not in a	2091	problems get reported to the code that tries to use the result, not in a
1824	random callback.	2092	random callback.
1825		2093
1826	All of this enables the following usage styles:	2094	All of this enables the following usage styles:
1827		2095
1828	1. Blocking:	2096	1. Blocking:
…		…
1876	through AnyEvent. The benchmark creates a lot of timers (with a zero	2144	through AnyEvent. The benchmark creates a lot of timers (with a zero
1877	timeout) and I/O watchers (watching STDOUT, a pty, to become writable,	2145	timeout) and I/O watchers (watching STDOUT, a pty, to become writable,
1878	which it is), lets them fire exactly once and destroys them again.	2146	which it is), lets them fire exactly once and destroys them again.
1879		2147
1880	Source code for this benchmark is found as F<eg/bench> in the AnyEvent	2148	Source code for this benchmark is found as F<eg/bench> in the AnyEvent
1881	distribution.	2149	distribution. It uses the L<AE> interface, which makes a real difference
		2150	for the EV and Perl backends only.
1882		2151
1883	=head3 Explanation of the columns	2152	=head3 Explanation of the columns
1884		2153
1885	I<watcher> is the number of event watchers created/destroyed. Since	2154	I<watcher> is the number of event watchers created/destroyed. Since
1886	different event models feature vastly different performances, each event	2155	different event models feature vastly different performances, each event
…		…
1907	watcher.	2176	watcher.
1908		2177
1909	=head3 Results	2178	=head3 Results
1910		2179
1911	name watchers bytes create invoke destroy comment	2180	name watchers bytes create invoke destroy comment
1912	EV/EV 400000 224 0.47 0.35 0.27 EV native interface	2181	EV/EV 100000 223 0.47 0.43 0.27 EV native interface
1913	EV/Any 100000 224 2.88 0.34 0.27 EV + AnyEvent watchers	2182	EV/Any 100000 223 0.48 0.42 0.26 EV + AnyEvent watchers
1914	CoroEV/Any 100000 224 2.85 0.35 0.28 coroutines + Coro::Signal	2183	Coro::EV/Any 100000 223 0.47 0.42 0.26 coroutines + Coro::Signal
1915	Perl/Any 100000 452 4.13 0.73 0.95 pure perl implementation	2184	Perl/Any 100000 431 2.70 0.74 0.92 pure perl implementation
1916	Event/Event 16000 517 32.20 31.80 0.81 Event native interface	2185	Event/Event 16000 516 31.16 31.84 0.82 Event native interface
1917	Event/Any 16000 590 35.85 31.55 1.06 Event + AnyEvent watchers	2186	Event/Any 16000 1203 42.61 34.79 1.80 Event + AnyEvent watchers
1918	IOAsync/Any 16000 989 38.10 32.77 11.13 via IO::Async::Loop::IO_Poll	2187	IOAsync/Any 16000 1911 41.92 27.45 16.81 via IO::Async::Loop::IO_Poll
1919	IOAsync/Any 16000 990 37.59 29.50 10.61 via IO::Async::Loop::Epoll	2188	IOAsync/Any 16000 1726 40.69 26.37 15.25 via IO::Async::Loop::Epoll
1920	Glib/Any 16000 1357 102.33 12.31 51.00 quadratic behaviour	2189	Glib/Any 16000 1118 89.00 12.57 51.17 quadratic behaviour
1921	Tk/Any 2000 1860 27.20 66.31 14.00 SEGV with >> 2000 watchers	2190	Tk/Any 2000 1346 20.96 10.75 8.00 SEGV with >> 2000 watchers
1922	POE/Event 2000 6328 109.99 751.67 14.02 via POE::Loop::Event	2191	POE/Any 2000 6951 108.97 795.32 14.24 via POE::Loop::Event
1923	POE/Select 2000 6027 94.54 809.13 579.80 via POE::Loop::Select	2192	POE/Any 2000 6648 94.79 774.40 575.51 via POE::Loop::Select
1924		2193
1925	=head3 Discussion	2194	=head3 Discussion
1926		2195
1927	The benchmark does I<not> measure scalability of the event loop very	2196	The benchmark does I<not> measure scalability of the event loop very
1928	well. For example, a select-based event loop (such as the pure perl one)	2197	well. For example, a select-based event loop (such as the pure perl one)
…		…
1940	benchmark machine, handling an event takes roughly 1600 CPU cycles with	2209	benchmark machine, handling an event takes roughly 1600 CPU cycles with
1941	EV, 3100 CPU cycles with AnyEvent's pure perl loop and almost 3000000 CPU	2210	EV, 3100 CPU cycles with AnyEvent's pure perl loop and almost 3000000 CPU
1942	cycles with POE.	2211	cycles with POE.
1943		2212
1944	C<EV> is the sole leader regarding speed and memory use, which are both	2213	C<EV> is the sole leader regarding speed and memory use, which are both
1945	maximal/minimal, respectively. Even when going through AnyEvent, it uses	2214	maximal/minimal, respectively. When using the L<AE> API there is zero
		2215	overhead (when going through the AnyEvent API create is about 5-6 times
		2216	slower, with other times being equal, so still uses far less memory than
1946	far less memory than any other event loop and is still faster than Event	2217	any other event loop and is still faster than Event natively).
1947	natively.
1948		2218
1949	The pure perl implementation is hit in a few sweet spots (both the	2219	The pure perl implementation is hit in a few sweet spots (both the
1950	constant timeout and the use of a single fd hit optimisations in the perl	2220	constant timeout and the use of a single fd hit optimisations in the perl
1951	interpreter and the backend itself). Nevertheless this shows that it	2221	interpreter and the backend itself). Nevertheless this shows that it
1952	adds very little overhead in itself. Like any select-based backend its	2222	adds very little overhead in itself. Like any select-based backend its
…		…
2026	In this benchmark, we use 10000 socket pairs (20000 sockets), of which 100	2296	In this benchmark, we use 10000 socket pairs (20000 sockets), of which 100
2027	(1%) are active. This mirrors the activity of large servers with many	2297	(1%) are active. This mirrors the activity of large servers with many
2028	connections, most of which are idle at any one point in time.	2298	connections, most of which are idle at any one point in time.
2029		2299
2030	Source code for this benchmark is found as F<eg/bench2> in the AnyEvent	2300	Source code for this benchmark is found as F<eg/bench2> in the AnyEvent
2031	distribution.	2301	distribution. It uses the L<AE> interface, which makes a real difference
		2302	for the EV and Perl backends only.
2032		2303
2033	=head3 Explanation of the columns	2304	=head3 Explanation of the columns
2034		2305
2035	I<sockets> is the number of sockets, and twice the number of "servers" (as	2306	I<sockets> is the number of sockets, and twice the number of "servers" (as
2036	each server has a read and write socket end).	2307	each server has a read and write socket end).
…		…
2044	a new one that moves the timeout into the future.	2315	a new one that moves the timeout into the future.
2045		2316
2046	=head3 Results	2317	=head3 Results
2047		2318
2048	name sockets create request	2319	name sockets create request
2049	EV 20000 69.01 11.16	2320	EV 20000 62.66 7.99
2050	Perl 20000 73.32 35.87	2321	Perl 20000 68.32 32.64
2051	IOAsync 20000 157.00 98.14 epoll	2322	IOAsync 20000 174.06 101.15 epoll
2052	IOAsync 20000 159.31 616.06 poll	2323	IOAsync 20000 174.67 610.84 poll
2053	Event 20000 212.62 257.32	2324	Event 20000 202.69 242.91
2054	Glib 20000 651.16 1896.30	2325	Glib 20000 557.01 1689.52
2055	POE 20000 349.67 12317.24 uses POE::Loop::Event	2326	POE 20000 341.54 12086.32 uses POE::Loop::Event
2056		2327
2057	=head3 Discussion	2328	=head3 Discussion
2058		2329
2059	This benchmark I<does> measure scalability and overall performance of the	2330	This benchmark I<does> measure scalability and overall performance of the
2060	particular event loop.	2331	particular event loop.
…		…
2186	As you can see, the AnyEvent + EV combination even beats the	2457	As you can see, the AnyEvent + EV combination even beats the
2187	hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl	2458	hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl
2188	backend easily beats IO::Lambda and POE.	2459	backend easily beats IO::Lambda and POE.
2189		2460
2190	And even the 100% non-blocking version written using the high-level (and	2461	And even the 100% non-blocking version written using the high-level (and
2191	slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda by a	2462	slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda
2192	large margin, even though it does all of DNS, tcp-connect and socket I/O	2463	higher level ("unoptimised") abstractions by a large margin, even though
2193	in a non-blocking way.	2464	it does all of DNS, tcp-connect and socket I/O in a non-blocking way.
2194		2465
2195	The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and	2466	The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and
2196	F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are	2467	F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are
2197	part of the IO::lambda distribution and were used without any changes.	2468	part of the IO::Lambda distribution and were used without any changes.
2198		2469
2199		2470
2200	=head1 SIGNALS	2471	=head1 SIGNALS
2201		2472
2202	AnyEvent currently installs handlers for these signals:	2473	AnyEvent currently installs handlers for these signals:
…		…
2244	it's built-in modules) are required to use it.	2515	it's built-in modules) are required to use it.
2245		2516
2246	That does not mean that AnyEvent won't take advantage of some additional	2517	That does not mean that AnyEvent won't take advantage of some additional
2247	modules if they are installed.	2518	modules if they are installed.
2248		2519
2249	This section epxlains which additional modules will be used, and how they	2520	This section explains which additional modules will be used, and how they
2250	affect AnyEvent's operetion.	2521	affect AnyEvent's operation.
2251		2522
2252	=over 4	2523	=over 4
2253		2524
2254	=item L<Async::Interrupt>	2525	=item L<Async::Interrupt>
2255		2526
2256	This slightly arcane module is used to implement fast signal handling: To	2527	This slightly arcane module is used to implement fast signal handling: To
2257	my knowledge, there is no way to do completely race-free and quick	2528	my knowledge, there is no way to do completely race-free and quick
2258	signal handling in pure perl. To ensure that signals still get	2529	signal handling in pure perl. To ensure that signals still get
2259	delivered, AnyEvent will start an interval timer to wake up perl (and	2530	delivered, AnyEvent will start an interval timer to wake up perl (and
2260	catch the signals) with soemd elay (default is 10 seconds, look for	2531	catch the signals) with some delay (default is 10 seconds, look for
2261	C<$AnyEvent::MAX_SIGNAL_LATENCY>).	2532	C<$AnyEvent::MAX_SIGNAL_LATENCY>).
2262		2533
2263	If this module is available, then it will be used to implement signal	2534	If this module is available, then it will be used to implement signal
2264	catching, which means that signals will not be delayed, and the event loop	2535	catching, which means that signals will not be delayed, and the event loop
2265	will not be interrupted regularly, which is more efficient (And good for	2536	will not be interrupted regularly, which is more efficient (and good for
2266	battery life on laptops).	2537	battery life on laptops).
2267		2538
2268	This affects not just the pure-perl event loop, but also other event loops	2539	This affects not just the pure-perl event loop, but also other event loops
2269	that have no signal handling on their own (e.g. Glib, Tk, Qt).	2540	that have no signal handling on their own (e.g. Glib, Tk, Qt).
		2541
		2542	Some event loops (POE, Event, Event::Lib) offer signal watchers natively,
		2543	and either employ their own workarounds (POE) or use AnyEvent's workaround
		2544	(using C<$AnyEvent::MAX_SIGNAL_LATENCY>). Installing L<Async::Interrupt>
		2545	does nothing for those backends.
2270		2546
2271	=item L<EV>	2547	=item L<EV>
2272		2548
2273	This module isn't really "optional", as it is simply one of the backend	2549	This module isn't really "optional", as it is simply one of the backend
2274	event loops that AnyEvent can use. However, it is simply the best event	2550	event loops that AnyEvent can use. However, it is simply the best event
…		…
2277	automatic timer adjustments even when no monotonic clock is available,	2553	automatic timer adjustments even when no monotonic clock is available,
2278	can take avdantage of advanced kernel interfaces such as C<epoll> and	2554	can take avdantage of advanced kernel interfaces such as C<epoll> and
2279	C<kqueue>, and is the fastest backend I<by far>. You can even embed	2555	C<kqueue>, and is the fastest backend I<by far>. You can even embed
2280	L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>).	2556	L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>).
2281		2557
		2558	If you only use backends that rely on another event loop (e.g. C<Tk>),
		2559	then this module will do nothing for you.
		2560
2282	=item L<Guard>	2561	=item L<Guard>
2283		2562
2284	The guard module, when used, will be used to implement	2563	The guard module, when used, will be used to implement
2285	C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a	2564	C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a
2286	lot less memory), but otherwise doesn't affect guard operation much. It is	2565	lot less memory), but otherwise doesn't affect guard operation much. It is
2287	purely used for performance.	2566	purely used for performance.
2288		2567
2289	=item L<JSON> and L<JSON::XS>	2568	=item L<JSON> and L<JSON::XS>
2290		2569
2291	This module is required when you want to read or write JSON data via	2570	One of these modules is required when you want to read or write JSON data
2292	L<AnyEvent::Handle>. It is also written in pure-perl, but can take	2571	via L<AnyEvent::Handle>. L<JSON> is also written in pure-perl, but can take
2293	advantage of the ulta-high-speed L<JSON::XS> module when it is installed.	2572	advantage of the ultra-high-speed L<JSON::XS> module when it is installed.
2294
2295	In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is
2296	installed.
2297		2573
2298	=item L<Net::SSLeay>	2574	=item L<Net::SSLeay>
2299		2575
2300	Implementing TLS/SSL in Perl is certainly interesting, but not very	2576	Implementing TLS/SSL in Perl is certainly interesting, but not very
2301	worthwhile: If this module is installed, then L<AnyEvent::Handle> (with	2577	worthwhile: If this module is installed, then L<AnyEvent::Handle> (with
…		…
2312		2588
2313		2589
2314	=head1 FORK	2590	=head1 FORK
2315		2591
2316	Most event libraries are not fork-safe. The ones who are usually are	2592	Most event libraries are not fork-safe. The ones who are usually are
2317	because they rely on inefficient but fork-safe C<select> or C<poll>	2593	because they rely on inefficient but fork-safe C<select> or C<poll> calls
2318	calls. Only L<EV> is fully fork-aware.	2594	- higher performance APIs such as BSD's kqueue or the dreaded Linux epoll
		2595	are usually badly thought-out hacks that are incompatible with fork in
		2596	one way or another. Only L<EV> is fully fork-aware and ensures that you
		2597	continue event-processing in both parent and child (or both, if you know
		2598	what you are doing).
		2599
		2600	This means that, in general, you cannot fork and do event processing in
		2601	the child if the event library was initialised before the fork (which
		2602	usually happens when the first AnyEvent watcher is created, or the library
		2603	is loaded).
2319		2604
2320	If you have to fork, you must either do so I<before> creating your first	2605	If you have to fork, you must either do so I<before> creating your first
2321	watcher OR you must not use AnyEvent at all in the child OR you must do	2606	watcher OR you must not use AnyEvent at all in the child OR you must do
2322	something completely out of the scope of AnyEvent.	2607	something completely out of the scope of AnyEvent.
		2608
		2609	The problem of doing event processing in the parent I<and> the child
		2610	is much more complicated: even for backends that I<are> fork-aware or
		2611	fork-safe, their behaviour is not usually what you want: fork clones all
		2612	watchers, that means all timers, I/O watchers etc. are active in both
		2613	parent and child, which is almost never what you want. USing C<exec>
		2614	to start worker children from some kind of manage rprocess is usually
		2615	preferred, because it is much easier and cleaner, at the expense of having
		2616	to have another binary.
2323		2617
2324		2618
2325	=head1 SECURITY CONSIDERATIONS	2619	=head1 SECURITY CONSIDERATIONS
2326		2620
2327	AnyEvent can be forced to load any event model via	2621	AnyEvent can be forced to load any event model via
…		…
2365	L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.	2659	L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.
2366		2660
2367	Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,	2661	Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,
2368	L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,	2662	L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,
2369	L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,	2663	L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,
2370	L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>.	2664	L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>.
2371		2665
2372	Non-blocking file handles, sockets, TCP clients and	2666	Non-blocking file handles, sockets, TCP clients and
2373	servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.	2667	servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.
2374		2668
2375	Asynchronous DNS: L<AnyEvent::DNS>.	2669	Asynchronous DNS: L<AnyEvent::DNS>.

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Comparing AnyEvent/lib/AnyEvent.pm (file contents): Revision 1.244 by root, Fri Jul 17 23:15:57 2009 UTC vs. Revision 1.329 by root, Sun Jul 11 05:44:22 2010 UTC

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Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.244 by root, Fri Jul 17 23:15:57 2009 UTC vs.
Revision 1.329 by root, Sun Jul 11 05:44:22 2010 UTC