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Revision 1.306 by root, Tue Dec 15 05:49:13 2009 UTC

1	=head1 NAME	1	=head1 NAME
2		2
3	AnyEvent - provide framework for multiple event loops	3	AnyEvent - the DBI of event loop programming
4		4
5	EV, Event, Glib, Tk, Perl, Event::Lib, Qt and POE are various supported	5	EV, Event, Glib, Tk, Perl, Event::Lib, Irssi, rxvt-unicode, IO::Async, Qt
6	event loops.	6	and POE are various supported event loops/environments.
7		7
8	=head1 SYNOPSIS	8	=head1 SYNOPSIS
9		9
10	use AnyEvent;	10	use AnyEvent;
11		11
…		…
40	=head1 INTRODUCTION/TUTORIAL	40	=head1 INTRODUCTION/TUTORIAL
41		41
42	This manpage is mainly a reference manual. If you are interested	42	This manpage is mainly a reference manual. If you are interested
43	in a tutorial or some gentle introduction, have a look at the	43	in a tutorial or some gentle introduction, have a look at the
44	L<AnyEvent::Intro> manpage.	44	L<AnyEvent::Intro> manpage.
		45
		46	=head1 SUPPORT
		47
		48	There is a mailinglist for discussing all things AnyEvent, and an IRC
		49	channel, too.
		50
		51	See the AnyEvent project page at the B<Schmorpforge Ta-Sa Software
		52	Repository>, at L<http://anyevent.schmorp.de>, for more info.
45		53
46	=head1 WHY YOU SHOULD USE THIS MODULE (OR NOT)	54	=head1 WHY YOU SHOULD USE THIS MODULE (OR NOT)
47		55
48	Glib, POE, IO::Async, Event... CPAN offers event models by the dozen	56	Glib, POE, IO::Async, Event... CPAN offers event models by the dozen
49	nowadays. So what is different about AnyEvent?	57	nowadays. So what is different about AnyEvent?
…		…
173	my variables are only visible after the statement in which they are	181	my variables are only visible after the statement in which they are
174	declared.	182	declared.
175		183
176	=head2 I/O WATCHERS	184	=head2 I/O WATCHERS
177		185
		186	$w = AnyEvent->io (
		187	fh => <filehandle_or_fileno>,
		188	poll => <"r" or "w">,
		189	cb => <callback>,
		190	);
		191
178	You can create an I/O watcher by calling the C<< AnyEvent->io >> method	192	You can create an I/O watcher by calling the C<< AnyEvent->io >> method
179	with the following mandatory key-value pairs as arguments:	193	with the following mandatory key-value pairs as arguments:
180		194
181	C<fh> is the Perl I<file handle> (I<not> file descriptor) to watch	195	C<fh> is the Perl I<file handle> (or a naked file descriptor) to watch
182	for events (AnyEvent might or might not keep a reference to this file	196	for events (AnyEvent might or might not keep a reference to this file
183	handle). Note that only file handles pointing to things for which	197	handle). Note that only file handles pointing to things for which
184	non-blocking operation makes sense are allowed. This includes sockets,	198	non-blocking operation makes sense are allowed. This includes sockets,
185	most character devices, pipes, fifos and so on, but not for example files	199	most character devices, pipes, fifos and so on, but not for example files
186	or block devices.	200	or block devices.
…		…
211	undef $w;	225	undef $w;
212	});	226	});
213		227
214	=head2 TIME WATCHERS	228	=head2 TIME WATCHERS
215		229
		230	$w = AnyEvent->timer (after => <seconds>, cb => <callback>);
		231
		232	$w = AnyEvent->timer (
		233	after => <fractional_seconds>,
		234	interval => <fractional_seconds>,
		235	cb => <callback>,
		236	);
		237
216	You can create a time watcher by calling the C<< AnyEvent->timer >>	238	You can create a time watcher by calling the C<< AnyEvent->timer >>
217	method with the following mandatory arguments:	239	method with the following mandatory arguments:
218		240
219	C<after> specifies after how many seconds (fractional values are	241	C<after> specifies after how many seconds (fractional values are
220	supported) the callback should be invoked. C<cb> is the callback to invoke	242	supported) the callback should be invoked. C<cb> is the callback to invoke
…		…
341	might affect timers and time-outs.	363	might affect timers and time-outs.
342		364
343	When this is the case, you can call this method, which will update the	365	When this is the case, you can call this method, which will update the
344	event loop's idea of "current time".	366	event loop's idea of "current time".
345		367
		368	A typical example would be a script in a web server (e.g. C<mod_perl>) -
		369	when mod_perl executes the script, then the event loop will have the wrong
		370	idea about the "current time" (being potentially far in the past, when the
		371	script ran the last time). In that case you should arrange a call to C<<
		372	AnyEvent->now_update >> each time the web server process wakes up again
		373	(e.g. at the start of your script, or in a handler).
		374
346	Note that updating the time I<might> cause some events to be handled.	375	Note that updating the time I<might> cause some events to be handled.
347		376
348	=back	377	=back
349		378
350	=head2 SIGNAL WATCHERS	379	=head2 SIGNAL WATCHERS
		380
		381	$w = AnyEvent->signal (signal => <uppercase_signal_name>, cb => <callback>);
351		382
352	You can watch for signals using a signal watcher, C<signal> is the signal	383	You can watch for signals using a signal watcher, C<signal> is the signal
353	I<name> in uppercase and without any C<SIG> prefix, C<cb> is the Perl	384	I<name> in uppercase and without any C<SIG> prefix, C<cb> is the Perl
354	callback to be invoked whenever a signal occurs.	385	callback to be invoked whenever a signal occurs.
355		386
…		…
361	invocation, and callback invocation will be synchronous. Synchronous means	392	invocation, and callback invocation will be synchronous. Synchronous means
362	that it might take a while until the signal gets handled by the process,	393	that it might take a while until the signal gets handled by the process,
363	but it is guaranteed not to interrupt any other callbacks.	394	but it is guaranteed not to interrupt any other callbacks.
364		395
365	The main advantage of using these watchers is that you can share a signal	396	The main advantage of using these watchers is that you can share a signal
366	between multiple watchers.	397	between multiple watchers, and AnyEvent will ensure that signals will not
		398	interrupt your program at bad times.
367		399
368	This watcher might use C<%SIG>, so programs overwriting those signals	400	This watcher might use C<%SIG> (depending on the event loop used),
369	directly will likely not work correctly.	401	so programs overwriting those signals directly will likely not work
		402	correctly.
370		403
371	Example: exit on SIGINT	404	Example: exit on SIGINT
372		405
373	my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });	406	my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
374		407
		408	=head3 Restart Behaviour
		409
		410	While restart behaviour is up to the event loop implementation, most will
		411	not restart syscalls (that includes L<Async::Interrupt> and AnyEvent's
		412	pure perl implementation).
		413
		414	=head3 Safe/Unsafe Signals
		415
		416	Perl signals can be either "safe" (synchronous to opcode handling) or
		417	"unsafe" (asynchronous) - the former might get delayed indefinitely, the
		418	latter might corrupt your memory.
		419
		420	AnyEvent signal handlers are, in addition, synchronous to the event loop,
		421	i.e. they will not interrupt your running perl program but will only be
		422	called as part of the normal event handling (just like timer, I/O etc.
		423	callbacks, too).
		424
		425	=head3 Signal Races, Delays and Workarounds
		426
		427	Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching
		428	callbacks to signals in a generic way, which is a pity, as you cannot
		429	do race-free signal handling in perl, requiring C libraries for
		430	this. AnyEvent will try to do it's best, which means in some cases,
		431	signals will be delayed. The maximum time a signal might be delayed is
		432	specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This
		433	variable can be changed only before the first signal watcher is created,
		434	and should be left alone otherwise. This variable determines how often
		435	AnyEvent polls for signals (in case a wake-up was missed). Higher values
		436	will cause fewer spurious wake-ups, which is better for power and CPU
		437	saving.
		438
		439	All these problems can be avoided by installing the optional
		440	L<Async::Interrupt> module, which works with most event loops. It will not
		441	work with inherently broken event loops such as L<Event> or L<Event::Lib>
		442	(and not with L<POE> currently, as POE does it's own workaround with
		443	one-second latency). For those, you just have to suffer the delays.
		444
375	=head2 CHILD PROCESS WATCHERS	445	=head2 CHILD PROCESS WATCHERS
376		446
		447	$w = AnyEvent->child (pid => <process id>, cb => <callback>);
		448
377	You can also watch on a child process exit and catch its exit status.	449	You can also watch on a child process exit and catch its exit status.
378		450
379	The child process is specified by the C<pid> argument (if set to C<0>, it	451	The child process is specified by the C<pid> argument (one some backends,
380	watches for any child process exit). The watcher will triggered only when	452	using C<0> watches for any child process exit, on others this will
381	the child process has finished and an exit status is available, not on	453	croak). The watcher will be triggered only when the child process has
382	any trace events (stopped/continued).	454	finished and an exit status is available, not on any trace events
		455	(stopped/continued).
383		456
384	The callback will be called with the pid and exit status (as returned by	457	The callback will be called with the pid and exit status (as returned by
385	waitpid), so unlike other watcher types, you I<can> rely on child watcher	458	waitpid), so unlike other watcher types, you I<can> rely on child watcher
386	callback arguments.	459	callback arguments.
387		460
…		…
392		465
393	There is a slight catch to child watchers, however: you usually start them	466	There is a slight catch to child watchers, however: you usually start them
394	I<after> the child process was created, and this means the process could	467	I<after> the child process was created, and this means the process could
395	have exited already (and no SIGCHLD will be sent anymore).	468	have exited already (and no SIGCHLD will be sent anymore).
396		469
397	Not all event models handle this correctly (POE doesn't), but even for	470	Not all event models handle this correctly (neither POE nor IO::Async do,
		471	see their AnyEvent::Impl manpages for details), but even for event models
398	event models that I<do> handle this correctly, they usually need to be	472	that I<do> handle this correctly, they usually need to be loaded before
399	loaded before the process exits (i.e. before you fork in the first place).	473	the process exits (i.e. before you fork in the first place). AnyEvent's
		474	pure perl event loop handles all cases correctly regardless of when you
		475	start the watcher.
400		476
401	This means you cannot create a child watcher as the very first thing in an	477	This means you cannot create a child watcher as the very first
402	AnyEvent program, you I<have> to create at least one watcher before you	478	thing in an AnyEvent program, you I<have> to create at least one
403	C<fork> the child (alternatively, you can call C<AnyEvent::detect>).	479	watcher before you C<fork> the child (alternatively, you can call
		480	C<AnyEvent::detect>).
		481
		482	As most event loops do not support waiting for child events, they will be
		483	emulated by AnyEvent in most cases, in which the latency and race problems
		484	mentioned in the description of signal watchers apply.
404		485
405	Example: fork a process and wait for it	486	Example: fork a process and wait for it
406		487
407	my $done = AnyEvent->condvar;	488	my $done = AnyEvent->condvar;
408		489
…		…
420	# do something else, then wait for process exit	501	# do something else, then wait for process exit
421	$done->recv;	502	$done->recv;
422		503
423	=head2 IDLE WATCHERS	504	=head2 IDLE WATCHERS
424		505
		506	$w = AnyEvent->idle (cb => <callback>);
		507
425	Sometimes there is a need to do something, but it is not so important	508	Sometimes there is a need to do something, but it is not so important
426	to do it instantly, but only when there is nothing better to do. This	509	to do it instantly, but only when there is nothing better to do. This
427	"nothing better to do" is usually defined to be "no other events need	510	"nothing better to do" is usually defined to be "no other events need
428	attention by the event loop".	511	attention by the event loop".
429		512
…		…
455	});	538	});
456	});	539	});
457		540
458	=head2 CONDITION VARIABLES	541	=head2 CONDITION VARIABLES
459		542
		543	$cv = AnyEvent->condvar;
		544
		545	$cv->send (<list>);
		546	my @res = $cv->recv;
		547
460	If you are familiar with some event loops you will know that all of them	548	If you are familiar with some event loops you will know that all of them
461	require you to run some blocking "loop", "run" or similar function that	549	require you to run some blocking "loop", "run" or similar function that
462	will actively watch for new events and call your callbacks.	550	will actively watch for new events and call your callbacks.
463		551
464	AnyEvent is different, it expects somebody else to run the event loop and	552	AnyEvent is slightly different: it expects somebody else to run the event
465	will only block when necessary (usually when told by the user).	553	loop and will only block when necessary (usually when told by the user).
466		554
467	The instrument to do that is called a "condition variable", so called	555	The instrument to do that is called a "condition variable", so called
468	because they represent a condition that must become true.	556	because they represent a condition that must become true.
469		557
		558	Now is probably a good time to look at the examples further below.
		559
470	Condition variables can be created by calling the C<< AnyEvent->condvar	560	Condition variables can be created by calling the C<< AnyEvent->condvar
471	>> method, usually without arguments. The only argument pair allowed is	561	>> method, usually without arguments. The only argument pair allowed is
472
473	C<cb>, which specifies a callback to be called when the condition variable	562	C<cb>, which specifies a callback to be called when the condition variable
474	becomes true, with the condition variable as the first argument (but not	563	becomes true, with the condition variable as the first argument (but not
475	the results).	564	the results).
476		565
477	After creation, the condition variable is "false" until it becomes "true"	566	After creation, the condition variable is "false" until it becomes "true"
…		…
482	Condition variables are similar to callbacks, except that you can	571	Condition variables are similar to callbacks, except that you can
483	optionally wait for them. They can also be called merge points - points	572	optionally wait for them. They can also be called merge points - points
484	in time where multiple outstanding events have been processed. And yet	573	in time where multiple outstanding events have been processed. And yet
485	another way to call them is transactions - each condition variable can be	574	another way to call them is transactions - each condition variable can be
486	used to represent a transaction, which finishes at some point and delivers	575	used to represent a transaction, which finishes at some point and delivers
487	a result.	576	a result. And yet some people know them as "futures" - a promise to
		577	compute/deliver something that you can wait for.
488		578
489	Condition variables are very useful to signal that something has finished,	579	Condition variables are very useful to signal that something has finished,
490	for example, if you write a module that does asynchronous http requests,	580	for example, if you write a module that does asynchronous http requests,
491	then a condition variable would be the ideal candidate to signal the	581	then a condition variable would be the ideal candidate to signal the
492	availability of results. The user can either act when the callback is	582	availability of results. The user can either act when the callback is
…		…
526	after => 1,	616	after => 1,
527	cb => sub { $result_ready->send },	617	cb => sub { $result_ready->send },
528	);	618	);
529		619
530	# this "blocks" (while handling events) till the callback	620	# this "blocks" (while handling events) till the callback
531	# calls send	621	# calls ->send
532	$result_ready->recv;	622	$result_ready->recv;
533		623
534	Example: wait for a timer, but take advantage of the fact that	624	Example: wait for a timer, but take advantage of the fact that condition
535	condition variables are also code references.	625	variables are also callable directly.
536		626
537	my $done = AnyEvent->condvar;	627	my $done = AnyEvent->condvar;
538	my $delay = AnyEvent->timer (after => 5, cb => $done);	628	my $delay = AnyEvent->timer (after => 5, cb => $done);
539	$done->recv;	629	$done->recv;
540		630
…		…
546		636
547	...	637	...
548		638
549	my @info = $couchdb->info->recv;	639	my @info = $couchdb->info->recv;
550		640
551	And this is how you would just ste a callback to be called whenever the	641	And this is how you would just set a callback to be called whenever the
552	results are available:	642	results are available:
553		643
554	$couchdb->info->cb (sub {	644	$couchdb->info->cb (sub {
555	my @info = $_[0]->recv;	645	my @info = $_[0]->recv;
556	});	646	});
…		…
574	immediately from within send.	664	immediately from within send.
575		665
576	Any arguments passed to the C<send> call will be returned by all	666	Any arguments passed to the C<send> call will be returned by all
577	future C<< ->recv >> calls.	667	future C<< ->recv >> calls.
578		668
579	Condition variables are overloaded so one can call them directly	669	Condition variables are overloaded so one can call them directly (as if
580	(as a code reference). Calling them directly is the same as calling	670	they were a code reference). Calling them directly is the same as calling
581	C<send>. Note, however, that many C-based event loops do not handle	671	C<send>.
582	overloading, so as tempting as it may be, passing a condition variable
583	instead of a callback does not work. Both the pure perl and EV loops
584	support overloading, however, as well as all functions that use perl to
585	invoke a callback (as in L<AnyEvent::Socket> and L<AnyEvent::DNS> for
586	example).
587		672
588	=item $cv->croak ($error)	673	=item $cv->croak ($error)
589		674
590	Similar to send, but causes all call's to C<< ->recv >> to invoke	675	Similar to send, but causes all call's to C<< ->recv >> to invoke
591	C<Carp::croak> with the given error message/object/scalar.	676	C<Carp::croak> with the given error message/object/scalar.
592		677
593	This can be used to signal any errors to the condition variable	678	This can be used to signal any errors to the condition variable
594	user/consumer.	679	user/consumer. Doing it this way instead of calling C<croak> directly
		680	delays the error detetcion, but has the overwhelmign advantage that it
		681	diagnoses the error at the place where the result is expected, and not
		682	deep in some event clalback without connection to the actual code causing
		683	the problem.
595		684
596	=item $cv->begin ([group callback])	685	=item $cv->begin ([group callback])
597		686
598	=item $cv->end	687	=item $cv->end
599
600	These two methods are EXPERIMENTAL and MIGHT CHANGE.
601		688
602	These two methods can be used to combine many transactions/events into	689	These two methods can be used to combine many transactions/events into
603	one. For example, a function that pings many hosts in parallel might want	690	one. For example, a function that pings many hosts in parallel might want
604	to use a condition variable for the whole process.	691	to use a condition variable for the whole process.
605		692
606	Every call to C<< ->begin >> will increment a counter, and every call to	693	Every call to C<< ->begin >> will increment a counter, and every call to
607	C<< ->end >> will decrement it. If the counter reaches C<0> in C<< ->end	694	C<< ->end >> will decrement it. If the counter reaches C<0> in C<< ->end
608	>>, the (last) callback passed to C<begin> will be executed. That callback	695	>>, the (last) callback passed to C<begin> will be executed, passing the
609	is I<supposed> to call C<< ->send >>, but that is not required. If no	696	condvar as first argument. That callback is I<supposed> to call C<< ->send
610	callback was set, C<send> will be called without any arguments.	697	>>, but that is not required. If no group callback was set, C<send> will
		698	be called without any arguments.
611		699
612	Let's clarify this with the ping example:	700	You can think of C<< $cv->send >> giving you an OR condition (one call
		701	sends), while C<< $cv->begin >> and C<< $cv->end >> giving you an AND
		702	condition (all C<begin> calls must be C<end>'ed before the condvar sends).
		703
		704	Let's start with a simple example: you have two I/O watchers (for example,
		705	STDOUT and STDERR for a program), and you want to wait for both streams to
		706	close before activating a condvar:
613		707
614	my $cv = AnyEvent->condvar;	708	my $cv = AnyEvent->condvar;
615		709
		710	$cv->begin; # first watcher
		711	my $w1 = AnyEvent->io (fh => $fh1, cb => sub {
		712	defined sysread $fh1, my $buf, 4096
		713	or $cv->end;
		714	});
		715
		716	$cv->begin; # second watcher
		717	my $w2 = AnyEvent->io (fh => $fh2, cb => sub {
		718	defined sysread $fh2, my $buf, 4096
		719	or $cv->end;
		720	});
		721
		722	$cv->recv;
		723
		724	This works because for every event source (EOF on file handle), there is
		725	one call to C<begin>, so the condvar waits for all calls to C<end> before
		726	sending.
		727
		728	The ping example mentioned above is slightly more complicated, as the
		729	there are results to be passwd back, and the number of tasks that are
		730	begung can potentially be zero:
		731
		732	my $cv = AnyEvent->condvar;
		733
616	my %result;	734	my %result;
617	$cv->begin (sub { $cv->send (\%result) });	735	$cv->begin (sub { shift->send (\%result) });
618		736
619	for my $host (@list_of_hosts) {	737	for my $host (@list_of_hosts) {
620	$cv->begin;	738	$cv->begin;
621	ping_host_then_call_callback $host, sub {	739	ping_host_then_call_callback $host, sub {
622	$result{$host} = ...;	740	$result{$host} = ...;
…		…
637	loop, which serves two important purposes: first, it sets the callback	755	loop, which serves two important purposes: first, it sets the callback
638	to be called once the counter reaches C<0>, and second, it ensures that	756	to be called once the counter reaches C<0>, and second, it ensures that
639	C<send> is called even when C<no> hosts are being pinged (the loop	757	C<send> is called even when C<no> hosts are being pinged (the loop
640	doesn't execute once).	758	doesn't execute once).
641		759
642	This is the general pattern when you "fan out" into multiple subrequests:	760	This is the general pattern when you "fan out" into multiple (but
643	use an outer C<begin>/C<end> pair to set the callback and ensure C<end>	761	potentially none) subrequests: use an outer C<begin>/C<end> pair to set
644	is called at least once, and then, for each subrequest you start, call	762	the callback and ensure C<end> is called at least once, and then, for each
645	C<begin> and for each subrequest you finish, call C<end>.	763	subrequest you start, call C<begin> and for each subrequest you finish,
		764	call C<end>.
646		765
647	=back	766	=back
648		767
649	=head3 METHODS FOR CONSUMERS	768	=head3 METHODS FOR CONSUMERS
650		769
…		…
666	function will call C<croak>.	785	function will call C<croak>.
667		786
668	In list context, all parameters passed to C<send> will be returned,	787	In list context, all parameters passed to C<send> will be returned,
669	in scalar context only the first one will be returned.	788	in scalar context only the first one will be returned.
670		789
		790	Note that doing a blocking wait in a callback is not supported by any
		791	event loop, that is, recursive invocation of a blocking C<< ->recv
		792	>> is not allowed, and the C<recv> call will C<croak> if such a
		793	condition is detected. This condition can be slightly loosened by using
		794	L<Coro::AnyEvent>, which allows you to do a blocking C<< ->recv >> from
		795	any thread that doesn't run the event loop itself.
		796
671	Not all event models support a blocking wait - some die in that case	797	Not all event models support a blocking wait - some die in that case
672	(programs might want to do that to stay interactive), so I<if you are	798	(programs might want to do that to stay interactive), so I<if you are
673	using this from a module, never require a blocking wait>, but let the	799	using this from a module, never require a blocking wait>. Instead, let the
674	caller decide whether the call will block or not (for example, by coupling	800	caller decide whether the call will block or not (for example, by coupling
675	condition variables with some kind of request results and supporting	801	condition variables with some kind of request results and supporting
676	callbacks so the caller knows that getting the result will not block,	802	callbacks so the caller knows that getting the result will not block,
677	while still supporting blocking waits if the caller so desires).	803	while still supporting blocking waits if the caller so desires).
678		804
679	Another reason I<never> to C<< ->recv >> in a module is that you cannot
680	sensibly have two C<< ->recv >>'s in parallel, as that would require
681	multiple interpreters or coroutines/threads, none of which C<AnyEvent>
682	can supply.
683
684	The L<Coro> module, however, I<can> and I<does> supply coroutines and, in
685	fact, L<Coro::AnyEvent> replaces AnyEvent's condvars by coroutine-safe
686	versions and also integrates coroutines into AnyEvent, making blocking
687	C<< ->recv >> calls perfectly safe as long as they are done from another
688	coroutine (one that doesn't run the event loop).
689
690	You can ensure that C<< -recv >> never blocks by setting a callback and	805	You can ensure that C<< -recv >> never blocks by setting a callback and
691	only calling C<< ->recv >> from within that callback (or at a later	806	only calling C<< ->recv >> from within that callback (or at a later
692	time). This will work even when the event loop does not support blocking	807	time). This will work even when the event loop does not support blocking
693	waits otherwise.	808	waits otherwise.
694		809
…		…
700	=item $cb = $cv->cb ($cb->($cv))	815	=item $cb = $cv->cb ($cb->($cv))
701		816
702	This is a mutator function that returns the callback set and optionally	817	This is a mutator function that returns the callback set and optionally
703	replaces it before doing so.	818	replaces it before doing so.
704		819
705	The callback will be called when the condition becomes "true", i.e. when	820	The callback will be called when the condition becomes (or already was)
706	C<send> or C<croak> are called, with the only argument being the condition	821	"true", i.e. when C<send> or C<croak> are called (or were called), with
707	variable itself. Calling C<recv> inside the callback or at any later time	822	the only argument being the condition variable itself. Calling C<recv>
708	is guaranteed not to block.	823	inside the callback or at any later time is guaranteed not to block.
709		824
710	=back	825	=back
711		826
		827	=head1 SUPPORTED EVENT LOOPS/BACKENDS
		828
		829	The available backend classes are (every class has its own manpage):
		830
		831	=over 4
		832
		833	=item Backends that are autoprobed when no other event loop can be found.
		834
		835	EV is the preferred backend when no other event loop seems to be in
		836	use. If EV is not installed, then AnyEvent will fall back to its own
		837	pure-perl implementation, which is available everywhere as it comes with
		838	AnyEvent itself.
		839
		840	AnyEvent::Impl::EV based on EV (interface to libev, best choice).
		841	AnyEvent::Impl::Perl pure-perl implementation, fast and portable.
		842
		843	=item Backends that are transparently being picked up when they are used.
		844
		845	These will be used when they are currently loaded when the first watcher
		846	is created, in which case it is assumed that the application is using
		847	them. This means that AnyEvent will automatically pick the right backend
		848	when the main program loads an event module before anything starts to
		849	create watchers. Nothing special needs to be done by the main program.
		850
		851	AnyEvent::Impl::Event based on Event, very stable, few glitches.
		852	AnyEvent::Impl::Glib based on Glib, slow but very stable.
		853	AnyEvent::Impl::Tk based on Tk, very broken.
		854	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
		855	AnyEvent::Impl::POE based on POE, very slow, some limitations.
		856	AnyEvent::Impl::Irssi used when running within irssi.
		857
		858	=item Backends with special needs.
		859
		860	Qt requires the Qt::Application to be instantiated first, but will
		861	otherwise be picked up automatically. As long as the main program
		862	instantiates the application before any AnyEvent watchers are created,
		863	everything should just work.
		864
		865	AnyEvent::Impl::Qt based on Qt.
		866
		867	Support for IO::Async can only be partial, as it is too broken and
		868	architecturally limited to even support the AnyEvent API. It also
		869	is the only event loop that needs the loop to be set explicitly, so
		870	it can only be used by a main program knowing about AnyEvent. See
		871	L<AnyEvent::Impl::Async> for the gory details.
		872
		873	AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed.
		874
		875	=item Event loops that are indirectly supported via other backends.
		876
		877	Some event loops can be supported via other modules:
		878
		879	There is no direct support for WxWidgets (L<Wx>) or L<Prima>.
		880
		881	B<WxWidgets> has no support for watching file handles. However, you can
		882	use WxWidgets through the POE adaptor, as POE has a Wx backend that simply
		883	polls 20 times per second, which was considered to be too horrible to even
		884	consider for AnyEvent.
		885
		886	B<Prima> is not supported as nobody seems to be using it, but it has a POE
		887	backend, so it can be supported through POE.
		888
		889	AnyEvent knows about both L<Prima> and L<Wx>, however, and will try to
		890	load L<POE> when detecting them, in the hope that POE will pick them up,
		891	in which case everything will be automatic.
		892
		893	=back
		894
712	=head1 GLOBAL VARIABLES AND FUNCTIONS	895	=head1 GLOBAL VARIABLES AND FUNCTIONS
713		896
		897	These are not normally required to use AnyEvent, but can be useful to
		898	write AnyEvent extension modules.
		899
714	=over 4	900	=over 4
715		901
716	=item $AnyEvent::MODEL	902	=item $AnyEvent::MODEL
717		903
718	Contains C<undef> until the first watcher is being created. Then it	904	Contains C<undef> until the first watcher is being created, before the
		905	backend has been autodetected.
		906
719	contains the event model that is being used, which is the name of the	907	Afterwards it contains the event model that is being used, which is the
720	Perl class implementing the model. This class is usually one of the	908	name of the Perl class implementing the model. This class is usually one
721	C<AnyEvent::Impl:xxx> modules, but can be any other class in the case	909	of the C<AnyEvent::Impl:xxx> modules, but can be any other class in the
722	AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode>).	910	case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it
723		911	will be C<urxvt::anyevent>).
724	The known classes so far are:
725
726	AnyEvent::Impl::EV based on EV (an interface to libev, best choice).
727	AnyEvent::Impl::Event based on Event, second best choice.
728	AnyEvent::Impl::Perl pure-perl implementation, fast and portable.
729	AnyEvent::Impl::Glib based on Glib, third-best choice.
730	AnyEvent::Impl::Tk based on Tk, very bad choice.
731	AnyEvent::Impl::Qt based on Qt, cannot be autoprobed (see its docs).
732	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
733	AnyEvent::Impl::POE based on POE, not generic enough for full support.
734
735	There is no support for WxWidgets, as WxWidgets has no support for
736	watching file handles. However, you can use WxWidgets through the
737	POE Adaptor, as POE has a Wx backend that simply polls 20 times per
738	second, which was considered to be too horrible to even consider for
739	AnyEvent. Likewise, other POE backends can be used by AnyEvent by using
740	it's adaptor.
741
742	AnyEvent knows about L<Prima> and L<Wx> and will try to use L<POE> when
743	autodetecting them.
744		912
745	=item AnyEvent::detect	913	=item AnyEvent::detect
746		914
747	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model	915	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model
748	if necessary. You should only call this function right before you would	916	if necessary. You should only call this function right before you would
749	have created an AnyEvent watcher anyway, that is, as late as possible at	917	have created an AnyEvent watcher anyway, that is, as late as possible at
750	runtime.	918	runtime, and not e.g. while initialising of your module.
		919
		920	If you need to do some initialisation before AnyEvent watchers are
		921	created, use C<post_detect>.
751		922
752	=item $guard = AnyEvent::post_detect { BLOCK }	923	=item $guard = AnyEvent::post_detect { BLOCK }
753		924
754	Arranges for the code block to be executed as soon as the event model is	925	Arranges for the code block to be executed as soon as the event model is
755	autodetected (or immediately if this has already happened).	926	autodetected (or immediately if this has already happened).
756		927
		928	The block will be executed I<after> the actual backend has been detected
		929	(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been
		930	created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do
		931	other initialisations - see the sources of L<AnyEvent::Strict> or
		932	L<AnyEvent::AIO> to see how this is used.
		933
		934	The most common usage is to create some global watchers, without forcing
		935	event module detection too early, for example, L<AnyEvent::AIO> creates
		936	and installs the global L<IO::AIO> watcher in a C<post_detect> block to
		937	avoid autodetecting the event module at load time.
		938
757	If called in scalar or list context, then it creates and returns an object	939	If called in scalar or list context, then it creates and returns an object
758	that automatically removes the callback again when it is destroyed. See	940	that automatically removes the callback again when it is destroyed (or
		941	C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for
759	L<Coro::BDB> for a case where this is useful.	942	a case where this is useful.
		943
		944	Example: Create a watcher for the IO::AIO module and store it in
		945	C<$WATCHER>. Only do so after the event loop is initialised, though.
		946
		947	our WATCHER;
		948
		949	my $guard = AnyEvent::post_detect {
		950	$WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb);
		951	};
		952
		953	# the ||= is important in case post_detect immediately runs the block,
		954	# as to not clobber the newly-created watcher. assigning both watcher and
		955	# post_detect guard to the same variable has the advantage of users being
		956	# able to just C<undef $WATCHER> if the watcher causes them grief.
		957
		958	$WATCHER ||= $guard;
760		959
761	=item @AnyEvent::post_detect	960	=item @AnyEvent::post_detect
762		961
763	If there are any code references in this array (you can C<push> to it	962	If there are any code references in this array (you can C<push> to it
764	before or after loading AnyEvent), then they will called directly after	963	before or after loading AnyEvent), then they will called directly after
765	the event loop has been chosen.	964	the event loop has been chosen.
766		965
767	You should check C<$AnyEvent::MODEL> before adding to this array, though:	966	You should check C<$AnyEvent::MODEL> before adding to this array, though:
768	if it contains a true value then the event loop has already been detected,	967	if it is defined then the event loop has already been detected, and the
769	and the array will be ignored.	968	array will be ignored.
770		969
771	Best use C<AnyEvent::post_detect { BLOCK }> instead.	970	Best use C<AnyEvent::post_detect { BLOCK }> when your application allows
		971	it, as it takes care of these details.
		972
		973	This variable is mainly useful for modules that can do something useful
		974	when AnyEvent is used and thus want to know when it is initialised, but do
		975	not need to even load it by default. This array provides the means to hook
		976	into AnyEvent passively, without loading it.
		977
		978	Example: To load Coro::AnyEvent whenever Coro and AnyEvent are used
		979	together, you could put this into Coro (this is the actual code used by
		980	Coro to accomplish this):
		981
		982	if (defined $AnyEvent::MODEL) {
		983	# AnyEvent already initialised, so load Coro::AnyEvent
		984	require Coro::AnyEvent;
		985	} else {
		986	# AnyEvent not yet initialised, so make sure to load Coro::AnyEvent
		987	# as soon as it is
		988	push @AnyEvent::post_detect, sub { require Coro::AnyEvent };
		989	}
772		990
773	=back	991	=back
774		992
775	=head1 WHAT TO DO IN A MODULE	993	=head1 WHAT TO DO IN A MODULE
776		994
…		…
831		1049
832		1050
833	=head1 OTHER MODULES	1051	=head1 OTHER MODULES
834		1052
835	The following is a non-exhaustive list of additional modules that use	1053	The following is a non-exhaustive list of additional modules that use
836	AnyEvent and can therefore be mixed easily with other AnyEvent modules	1054	AnyEvent as a client and can therefore be mixed easily with other AnyEvent
837	in the same program. Some of the modules come with AnyEvent, some are	1055	modules and other event loops in the same program. Some of the modules
838	available via CPAN.	1056	come with AnyEvent, most are available via CPAN.
839		1057
840	=over 4	1058	=over 4
841		1059
842	=item L<AnyEvent::Util>	1060	=item L<AnyEvent::Util>
843		1061
…		…
852		1070
853	=item L<AnyEvent::Handle>	1071	=item L<AnyEvent::Handle>
854		1072
855	Provide read and write buffers, manages watchers for reads and writes,	1073	Provide read and write buffers, manages watchers for reads and writes,
856	supports raw and formatted I/O, I/O queued and fully transparent and	1074	supports raw and formatted I/O, I/O queued and fully transparent and
857	non-blocking SSL/TLS.	1075	non-blocking SSL/TLS (via L<AnyEvent::TLS>.
858		1076
859	=item L<AnyEvent::DNS>	1077	=item L<AnyEvent::DNS>
860		1078
861	Provides rich asynchronous DNS resolver capabilities.	1079	Provides rich asynchronous DNS resolver capabilities.
862		1080
…		…
890		1108
891	=item L<AnyEvent::GPSD>	1109	=item L<AnyEvent::GPSD>
892		1110
893	A non-blocking interface to gpsd, a daemon delivering GPS information.	1111	A non-blocking interface to gpsd, a daemon delivering GPS information.
894		1112
		1113	=item L<AnyEvent::IRC>
		1114
		1115	AnyEvent based IRC client module family (replacing the older Net::IRC3).
		1116
		1117	=item L<AnyEvent::XMPP>
		1118
		1119	AnyEvent based XMPP (Jabber protocol) module family (replacing the older
		1120	Net::XMPP2>.
		1121
895	=item L<AnyEvent::IGS>	1122	=item L<AnyEvent::IGS>
896		1123
897	A non-blocking interface to the Internet Go Server protocol (used by	1124	A non-blocking interface to the Internet Go Server protocol (used by
898	L<App::IGS>).	1125	L<App::IGS>).
899		1126
900	=item L<AnyEvent::IRC>
901
902	AnyEvent based IRC client module family (replacing the older Net::IRC3).
903
904	=item L<Net::XMPP2>
905
906	AnyEvent based XMPP (Jabber protocol) module family.
907
908	=item L<Net::FCP>	1127	=item L<Net::FCP>
909		1128
910	AnyEvent-based implementation of the Freenet Client Protocol, birthplace	1129	AnyEvent-based implementation of the Freenet Client Protocol, birthplace
911	of AnyEvent.	1130	of AnyEvent.
912		1131
…		…
916		1135
917	=item L<Coro>	1136	=item L<Coro>
918		1137
919	Has special support for AnyEvent via L<Coro::AnyEvent>.	1138	Has special support for AnyEvent via L<Coro::AnyEvent>.
920		1139
921	=item L<IO::Lambda>
922
923	The lambda approach to I/O - don't ask, look there. Can use AnyEvent.
924
925	=back	1140	=back
926		1141
927	=cut	1142	=cut
928		1143
929	package AnyEvent;	1144	package AnyEvent;
930		1145
931	no warnings;	1146	# basically a tuned-down version of common::sense
932	use strict qw(vars subs);	1147	sub common_sense {
		1148	# from common:.sense 1.0
		1149	${^WARNING_BITS} = "\xfc\x3f\x33\x00\x0f\xf3\xcf\xc0\xf3\xfc\x33\x00";
		1150	# use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl)
		1151	$^H |= 0x00000600;
		1152	}
933		1153
		1154	BEGIN { AnyEvent::common_sense }
		1155
934	use Carp;	1156	use Carp ();
935		1157
936	our $VERSION = 4.411;	1158	our $VERSION = '5.22';
937	our $MODEL;	1159	our $MODEL;
938		1160
939	our $AUTOLOAD;	1161	our $AUTOLOAD;
940	our @ISA;	1162	our @ISA;
941		1163
942	our @REGISTRY;	1164	our @REGISTRY;
943		1165
944	our $WIN32;	1166	our $VERBOSE;
945		1167
946	BEGIN {	1168	BEGIN {
947	eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }";	1169	eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }";
948	eval "sub TAINT(){ " . (${^TAINT}*1) . " }";	1170	eval "sub TAINT(){ " . (${^TAINT}*1) . " }";
949		1171
950	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}	1172	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}
951	if ${^TAINT};	1173	if ${^TAINT};
952	}
953		1174
954	our $verbose = $ENV{PERL_ANYEVENT_VERBOSE}*1;	1175	$VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1;
		1176
		1177	}
		1178
		1179	our $MAX_SIGNAL_LATENCY = 10;
955		1180
956	our %PROTOCOL; # (ipv4|ipv6) => (1|2), higher numbers are preferred	1181	our %PROTOCOL; # (ipv4|ipv6) => (1|2), higher numbers are preferred
957		1182
958	{	1183	{
959	my $idx;	1184	my $idx;
…		…
961	for reverse split /\s*,\s*/,	1186	for reverse split /\s*,\s*/,
962	$ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6";	1187	$ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6";
963	}	1188	}
964		1189
965	my @models = (	1190	my @models = (
966	[EV:: => AnyEvent::Impl::EV::],	1191	[EV:: => AnyEvent::Impl::EV:: , 1],
967	[Event:: => AnyEvent::Impl::Event::],
968	[AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::],	1192	[AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl:: , 1],
969	# everything below here will not be autoprobed	1193	# everything below here will not (normally) be autoprobed
970	# as the pureperl backend should work everywhere	1194	# as the pureperl backend should work everywhere
971	# and is usually faster	1195	# and is usually faster
		1196	[Event:: => AnyEvent::Impl::Event::, 1],
		1197	[Glib:: => AnyEvent::Impl::Glib:: , 1], # becomes extremely slow with many watchers
		1198	[Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
		1199	[Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package
972	[Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles	1200	[Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
973	[Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers
974	[Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
975	[Qt:: => AnyEvent::Impl::Qt::], # requires special main program	1201	[Qt:: => AnyEvent::Impl::Qt::], # requires special main program
976	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza	1202	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
977	[Wx:: => AnyEvent::Impl::POE::],	1203	[Wx:: => AnyEvent::Impl::POE::],
978	[Prima:: => AnyEvent::Impl::POE::],	1204	[Prima:: => AnyEvent::Impl::POE::],
		1205	# IO::Async is just too broken - we would need workarounds for its
		1206	# byzantine signal and broken child handling, among others.
		1207	# IO::Async is rather hard to detect, as it doesn't have any
		1208	# obvious default class.
		1209	[IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program
		1210	[IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program
		1211	[IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program
		1212	[AnyEvent::Impl::IOAsync:: => AnyEvent::Impl::IOAsync::], # requires special main program
979	);	1213	);
980		1214
981	our %method = map +($_ => 1),	1215	our %method = map +($_ => 1),
982	qw(io timer time now now_update signal child idle condvar one_event DESTROY);	1216	qw(io timer time now now_update signal child idle condvar one_event DESTROY);
983		1217
…		…
987	my ($cb) = @_;	1221	my ($cb) = @_;
988		1222
989	if ($MODEL) {	1223	if ($MODEL) {
990	$cb->();	1224	$cb->();
991		1225
992	1	1226	undef
993	} else {	1227	} else {
994	push @post_detect, $cb;	1228	push @post_detect, $cb;
995		1229
996	defined wantarray	1230	defined wantarray
997	? bless \$cb, "AnyEvent::Util::postdetect"	1231	? bless \$cb, "AnyEvent::Util::postdetect"
…		…
1003	@post_detect = grep $_ != ${$_[0]}, @post_detect;	1237	@post_detect = grep $_ != ${$_[0]}, @post_detect;
1004	}	1238	}
1005		1239
1006	sub detect() {	1240	sub detect() {
1007	unless ($MODEL) {	1241	unless ($MODEL) {
1008	no strict 'refs';
1009	local $SIG{__DIE__};	1242	local $SIG{__DIE__};
1010		1243
1011	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {	1244	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {
1012	my $model = "AnyEvent::Impl::$1";	1245	my $model = "AnyEvent::Impl::$1";
1013	if (eval "require $model") {	1246	if (eval "require $model") {
1014	$MODEL = $model;	1247	$MODEL = $model;
1015	warn "AnyEvent: loaded model '$model' (forced by \$PERL_ANYEVENT_MODEL), using it.\n" if $verbose > 1;	1248	warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2;
1016	} else {	1249	} else {
1017	warn "AnyEvent: unable to load model '$model' (from \$PERL_ANYEVENT_MODEL):\n$@" if $verbose;	1250	warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE;
1018	}	1251	}
1019	}	1252	}
1020		1253
1021	# check for already loaded models	1254	# check for already loaded models
1022	unless ($MODEL) {	1255	unless ($MODEL) {
1023	for (@REGISTRY, @models) {	1256	for (@REGISTRY, @models) {
1024	my ($package, $model) = @$_;	1257	my ($package, $model) = @$_;
1025	if (${"$package\::VERSION"} > 0) {	1258	if (${"$package\::VERSION"} > 0) {
1026	if (eval "require $model") {	1259	if (eval "require $model") {
1027	$MODEL = $model;	1260	$MODEL = $model;
1028	warn "AnyEvent: autodetected model '$model', using it.\n" if $verbose > 1;	1261	warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2;
1029	last;	1262	last;
1030	}	1263	}
1031	}	1264	}
1032	}	1265	}
1033		1266
1034	unless ($MODEL) {	1267	unless ($MODEL) {
1035	# try to load a model	1268	# try to autoload a model
1036
1037	for (@REGISTRY, @models) {	1269	for (@REGISTRY, @models) {
1038	my ($package, $model) = @$_;	1270	my ($package, $model, $autoload) = @$_;
		1271	if (
		1272	$autoload
1039	if (eval "require $package"	1273	and eval "require $package"
1040	and ${"$package\::VERSION"} > 0	1274	and ${"$package\::VERSION"} > 0
1041	and eval "require $model") {	1275	and eval "require $model"
		1276	) {
1042	$MODEL = $model;	1277	$MODEL = $model;
1043	warn "AnyEvent: autoprobed model '$model', using it.\n" if $verbose > 1;	1278	warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2;
1044	last;	1279	last;
1045	}	1280	}
1046	}	1281	}
1047		1282
1048	$MODEL	1283	$MODEL
…		…
1064		1299
1065	sub AUTOLOAD {	1300	sub AUTOLOAD {
1066	(my $func = $AUTOLOAD) =~ s/.*://;	1301	(my $func = $AUTOLOAD) =~ s/.*://;
1067		1302
1068	$method{$func}	1303	$method{$func}
1069	or croak "$func: not a valid method for AnyEvent objects";	1304	or Carp::croak "$func: not a valid method for AnyEvent objects";
1070		1305
1071	detect unless $MODEL;	1306	detect unless $MODEL;
1072		1307
1073	my $class = shift;	1308	my $class = shift;
1074	$class->$func (@_);	1309	$class->$func (@_);
1075	}	1310	}
1076		1311
1077	# utility function to dup a filehandle. this is used by many backends	1312	# utility function to dup a filehandle. this is used by many backends
1078	# to support binding more than one watcher per filehandle (they usually	1313	# to support binding more than one watcher per filehandle (they usually
1079	# allow only one watcher per fd, so we dup it to get a different one).	1314	# allow only one watcher per fd, so we dup it to get a different one).
1080	sub _dupfh($$$$) {	1315	sub _dupfh($$;$$) {
1081	my ($poll, $fh, $r, $w) = @_;	1316	my ($poll, $fh, $r, $w) = @_;
1082		1317
1083	# cygwin requires the fh mode to be matching, unix doesn't	1318	# cygwin requires the fh mode to be matching, unix doesn't
1084	my ($rw, $mode) = $poll eq "r" ? ($r, "<")	1319	my ($rw, $mode) = $poll eq "r" ? ($r, "<&") : ($w, ">&");
1085	: $poll eq "w" ? ($w, ">")
1086	: Carp::croak "AnyEvent->io requires poll set to either 'r' or 'w'";
1087		1320
1088	open my $fh2, "$mode&" . fileno $fh	1321	open my $fh2, $mode, $fh
1089	or die "cannot dup() filehandle: $!,";	1322	or die "AnyEvent->io: cannot dup() filehandle in mode '$poll': $!,";
1090		1323
1091	# we assume CLOEXEC is already set by perl in all important cases	1324	# we assume CLOEXEC is already set by perl in all important cases
1092		1325
1093	($fh2, $rw)	1326	($fh2, $rw)
1094	}	1327	}
1095		1328
		1329	=head1 SIMPLIFIED AE API
		1330
		1331	Starting with version 5.0, AnyEvent officially supports a second, much
		1332	simpler, API that is designed to reduce the calling, typing and memory
		1333	overhead.
		1334
		1335	See the L<AE> manpage for details.
		1336
		1337	=cut
		1338
		1339	package AE;
		1340
		1341	our $VERSION = $AnyEvent::VERSION;
		1342
		1343	sub io($$$) {
		1344	AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])
		1345	}
		1346
		1347	sub timer($$$) {
		1348	AnyEvent->timer (after => $_[0], interval => $_[1], cb => $_[2])
		1349	}
		1350
		1351	sub signal($$) {
		1352	AnyEvent->signal (signal => $_[0], cb => $_[1])
		1353	}
		1354
		1355	sub child($$) {
		1356	AnyEvent->child (pid => $_[0], cb => $_[1])
		1357	}
		1358
		1359	sub idle($) {
		1360	AnyEvent->idle (cb => $_[0])
		1361	}
		1362
		1363	sub cv(;&) {
		1364	AnyEvent->condvar (@_ ? (cb => $_[0]) : ())
		1365	}
		1366
		1367	sub now() {
		1368	AnyEvent->now
		1369	}
		1370
		1371	sub now_update() {
		1372	AnyEvent->now_update
		1373	}
		1374
		1375	sub time() {
		1376	AnyEvent->time
		1377	}
		1378
1096	package AnyEvent::Base;	1379	package AnyEvent::Base;
1097		1380
1098	# default implementations for many methods	1381	# default implementations for many methods
1099		1382
1100	BEGIN {	1383	sub _time() {
		1384	# probe for availability of Time::HiRes
1101	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {	1385	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
		1386	warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8;
1102	*_time = \&Time::HiRes::time;	1387	*_time = \&Time::HiRes::time;
1103	# if (eval "use POSIX (); (POSIX::times())...	1388	# if (eval "use POSIX (); (POSIX::times())...
1104	} else {	1389	} else {
		1390	warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE;
1105	*_time = sub { time }; # epic fail	1391	*_time = sub { time }; # epic fail
1106	}	1392	}
		1393
		1394	&_time
1107	}	1395	}
1108		1396
1109	sub time { _time }	1397	sub time { _time }
1110	sub now { _time }	1398	sub now { _time }
1111	sub now_update { }	1399	sub now_update { }
…		…
1116	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"	1404	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"
1117	}	1405	}
1118		1406
1119	# default implementation for ->signal	1407	# default implementation for ->signal
1120		1408
		1409	our $HAVE_ASYNC_INTERRUPT;
		1410
		1411	sub _have_async_interrupt() {
		1412	$HAVE_ASYNC_INTERRUPT = 1*(!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT}
		1413	&& eval "use Async::Interrupt 1.02 (); 1")
		1414	unless defined $HAVE_ASYNC_INTERRUPT;
		1415
		1416	$HAVE_ASYNC_INTERRUPT
		1417	}
		1418
1121	our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);	1419	our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);
		1420	our (%SIG_ASY, %SIG_ASY_W);
		1421	our ($SIG_COUNT, $SIG_TW);
1122		1422
1123	sub _signal_exec {	1423	sub _signal_exec {
		1424	$HAVE_ASYNC_INTERRUPT
		1425	? $SIGPIPE_R->drain
1124	sysread $SIGPIPE_R, my $dummy, 4;	1426	: sysread $SIGPIPE_R, (my $dummy), 9;
1125		1427
1126	while (%SIG_EV) {	1428	while (%SIG_EV) {
1127	for (keys %SIG_EV) {	1429	for (keys %SIG_EV) {
1128	delete $SIG_EV{$_};	1430	delete $SIG_EV{$_};
1129	$_->() for values %{ $SIG_CB{$_} || {} };	1431	$_->() for values %{ $SIG_CB{$_} || {} };
1130	}	1432	}
1131	}	1433	}
1132	}	1434	}
1133		1435
		1436	# install a dummy wakeup watcher to reduce signal catching latency
		1437	sub _sig_add() {
		1438	unless ($SIG_COUNT++) {
		1439	# try to align timer on a full-second boundary, if possible
		1440	my $NOW = AE::now;
		1441
		1442	$SIG_TW = AE::timer
		1443	$MAX_SIGNAL_LATENCY - ($NOW - int $NOW),
		1444	$MAX_SIGNAL_LATENCY,
		1445	sub { } # just for the PERL_ASYNC_CHECK
		1446	;
		1447	}
		1448	}
		1449
		1450	sub _sig_del {
		1451	undef $SIG_TW
		1452	unless --$SIG_COUNT;
		1453	}
		1454
		1455	our $_sig_name_init; $_sig_name_init = sub {
		1456	eval q{ # poor man's autoloading
		1457	undef $_sig_name_init;
		1458
		1459	if (_have_async_interrupt) {
		1460	*sig2num = \&Async::Interrupt::sig2num;
		1461	*sig2name = \&Async::Interrupt::sig2name;
		1462	} else {
		1463	require Config;
		1464
		1465	my %signame2num;
		1466	@signame2num{ split ' ', $Config::Config{sig_name} }
		1467	= split ' ', $Config::Config{sig_num};
		1468
		1469	my @signum2name;
		1470	@signum2name[values %signame2num] = keys %signame2num;
		1471
		1472	*sig2num = sub($) {
		1473	$_[0] > 0 ? shift : $signame2num{+shift}
		1474	};
		1475	*sig2name = sub ($) {
		1476	$_[0] > 0 ? $signum2name[+shift] : shift
		1477	};
		1478	}
		1479	};
		1480	die if $@;
		1481	};
		1482
		1483	sub sig2num ($) { &$_sig_name_init; &sig2num }
		1484	sub sig2name($) { &$_sig_name_init; &sig2name }
		1485
1134	sub signal {	1486	sub signal {
1135	my (undef, %arg) = @_;	1487	eval q{ # poor man's autoloading {}
		1488	# probe for availability of Async::Interrupt
		1489	if (_have_async_interrupt) {
		1490	warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8;
1136		1491
1137	unless ($SIGPIPE_R) {	1492	$SIGPIPE_R = new Async::Interrupt::EventPipe;
1138	require Fcntl;	1493	$SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;
1139		1494
1140	if (AnyEvent::WIN32) {
1141	require AnyEvent::Util;
1142
1143	($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
1144	AnyEvent::Util::fh_nonblocking ($SIGPIPE_R) if $SIGPIPE_R;
1145	AnyEvent::Util::fh_nonblocking ($SIGPIPE_W) if $SIGPIPE_W; # just in case
1146	} else {	1495	} else {
		1496	warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;
		1497
		1498	require Fcntl;
		1499
		1500	if (AnyEvent::WIN32) {
		1501	require AnyEvent::Util;
		1502
		1503	($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
		1504	AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R;
		1505	AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case
		1506	} else {
1147	pipe $SIGPIPE_R, $SIGPIPE_W;	1507	pipe $SIGPIPE_R, $SIGPIPE_W;
1148	fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R;	1508	fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R;
1149	fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case	1509	fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case
1150		1510
1151	# not strictly required, as $^F is normally 2, but let's make sure...	1511	# not strictly required, as $^F is normally 2, but let's make sure...
1152	fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;	1512	fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
1153	fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;	1513	fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;
		1514	}
		1515
		1516	$SIGPIPE_R
		1517	or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
		1518
		1519	$SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec;
1154	}	1520	}
1155		1521
1156	$SIGPIPE_R	1522	*signal = sub {
1157	or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";	1523	my (undef, %arg) = @_;
1158		1524
1159	$SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec);
1160	}
1161
1162	my $signal = uc $arg{signal}	1525	my $signal = uc $arg{signal}
1163	or Carp::croak "required option 'signal' is missing";	1526	or Carp::croak "required option 'signal' is missing";
1164		1527
		1528	if ($HAVE_ASYNC_INTERRUPT) {
		1529	# async::interrupt
		1530
		1531	$signal = sig2num $signal;
1165	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};	1532	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};
		1533
		1534	$SIG_ASY{$signal} ||= new Async::Interrupt
		1535	cb => sub { undef $SIG_EV{$signal} },
		1536	signal => $signal,
		1537	pipe => [$SIGPIPE_R->filenos],
		1538	pipe_autodrain => 0,
		1539	;
		1540
		1541	} else {
		1542	# pure perl
		1543
		1544	# AE::Util has been loaded in signal
		1545	$signal = sig2name $signal;
		1546	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};
		1547
1166	$SIG{$signal} ||= sub {	1548	$SIG{$signal} ||= sub {
1167	local $!;	1549	local $!;
1168	syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;	1550	syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
1169	undef $SIG_EV{$signal};	1551	undef $SIG_EV{$signal};
		1552	};
		1553
		1554	# can't do signal processing without introducing races in pure perl,
		1555	# so limit the signal latency.
		1556	_sig_add;
		1557	}
		1558
		1559	bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
		1560	};
		1561
		1562	*AnyEvent::Base::signal::DESTROY = sub {
		1563	my ($signal, $cb) = @{$_[0]};
		1564
		1565	_sig_del;
		1566
		1567	delete $SIG_CB{$signal}{$cb};
		1568
		1569	$HAVE_ASYNC_INTERRUPT
		1570	? delete $SIG_ASY{$signal}
		1571	: # delete doesn't work with older perls - they then
		1572	# print weird messages, or just unconditionally exit
		1573	# instead of getting the default action.
		1574	undef $SIG{$signal}
		1575	unless keys %{ $SIG_CB{$signal} };
		1576	};
1170	};	1577	};
1171		1578	die if $@;
1172	bless [$signal, $arg{cb}], "AnyEvent::Base::signal"	1579	&signal
1173	}
1174
1175	sub AnyEvent::Base::signal::DESTROY {
1176	my ($signal, $cb) = @{$_[0]};
1177
1178	delete $SIG_CB{$signal}{$cb};
1179
1180	# delete doesn't work with older perls - they then
1181	# print weird messages, or just unconditionally exit
1182	# instead of getting the default action.
1183	undef $SIG{$signal} unless keys %{ $SIG_CB{$signal} };
1184	}	1580	}
1185		1581
1186	# default implementation for ->child	1582	# default implementation for ->child
1187		1583
1188	our %PID_CB;	1584	our %PID_CB;
1189	our $CHLD_W;	1585	our $CHLD_W;
1190	our $CHLD_DELAY_W;	1586	our $CHLD_DELAY_W;
1191	our $WNOHANG;	1587	our $WNOHANG;
1192		1588
		1589	sub _emit_childstatus($$) {
		1590	my (undef, $rpid, $rstatus) = @_;
		1591
		1592	$_->($rpid, $rstatus)
		1593	for values %{ $PID_CB{$rpid} || {} },
		1594	values %{ $PID_CB{0} || {} };
		1595	}
		1596
1193	sub _sigchld {	1597	sub _sigchld {
		1598	my $pid;
		1599
		1600	AnyEvent->_emit_childstatus ($pid, $?)
1194	while (0 < (my $pid = waitpid -1, $WNOHANG)) {	1601	while ($pid = waitpid -1, $WNOHANG) > 0;
1195	$_->($pid, $?) for (values %{ $PID_CB{$pid} || {} }),
1196	(values %{ $PID_CB{0} || {} });
1197	}
1198	}	1602	}
1199		1603
1200	sub child {	1604	sub child {
1201	my (undef, %arg) = @_;	1605	my (undef, %arg) = @_;
1202		1606
1203	defined (my $pid = $arg{pid} + 0)	1607	defined (my $pid = $arg{pid} + 0)
1204	or Carp::croak "required option 'pid' is missing";	1608	or Carp::croak "required option 'pid' is missing";
1205		1609
1206	$PID_CB{$pid}{$arg{cb}} = $arg{cb};	1610	$PID_CB{$pid}{$arg{cb}} = $arg{cb};
1207		1611
		1612	# WNOHANG is almost cetrainly 1 everywhere
		1613	$WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/
		1614	? 1
1208	$WNOHANG ||= eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1;	1615	: eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1;
1209		1616
1210	unless ($CHLD_W) {	1617	unless ($CHLD_W) {
1211	$CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld);	1618	$CHLD_W = AE::signal CHLD => \&_sigchld;
1212	# child could be a zombie already, so make at least one round	1619	# child could be a zombie already, so make at least one round
1213	&_sigchld;	1620	&_sigchld;
1214	}	1621	}
1215		1622
1216	bless [$pid, $arg{cb}], "AnyEvent::Base::child"	1623	bless [$pid, $arg{cb}], "AnyEvent::Base::child"
…		…
1242	# never use more then 50% of the time for the idle watcher,	1649	# never use more then 50% of the time for the idle watcher,
1243	# within some limits	1650	# within some limits
1244	$w = 0.0001 if $w < 0.0001;	1651	$w = 0.0001 if $w < 0.0001;
1245	$w = 5 if $w > 5;	1652	$w = 5 if $w > 5;
1246		1653
1247	$w = AnyEvent->timer (after => $w, cb => $rcb);	1654	$w = AE::timer $w, 0, $rcb;
1248	} else {	1655	} else {
1249	# clean up...	1656	# clean up...
1250	undef $w;	1657	undef $w;
1251	undef $rcb;	1658	undef $rcb;
1252	}	1659	}
1253	};	1660	};
1254		1661
1255	$w = AnyEvent->timer (after => 0.05, cb => $rcb);	1662	$w = AE::timer 0.05, 0, $rcb;
1256		1663
1257	bless \\$cb, "AnyEvent::Base::idle"	1664	bless \\$cb, "AnyEvent::Base::idle"
1258	}	1665	}
1259		1666
1260	sub AnyEvent::Base::idle::DESTROY {	1667	sub AnyEvent::Base::idle::DESTROY {
…		…
1265		1672
1266	our @ISA = AnyEvent::CondVar::Base::;	1673	our @ISA = AnyEvent::CondVar::Base::;
1267		1674
1268	package AnyEvent::CondVar::Base;	1675	package AnyEvent::CondVar::Base;
1269		1676
1270	use overload	1677	#use overload
1271	'&{}' => sub { my $self = shift; sub { $self->send (@_) } },	1678	# '&{}' => sub { my $self = shift; sub { $self->send (@_) } },
1272	fallback => 1;	1679	# fallback => 1;
		1680
		1681	# save 300+ kilobytes by dirtily hardcoding overloading
		1682	${"AnyEvent::CondVar::Base::OVERLOAD"}{dummy}++; # Register with magic by touching.
		1683	*{'AnyEvent::CondVar::Base::()'} = sub { }; # "Make it findable via fetchmethod."
		1684	*{'AnyEvent::CondVar::Base::(&{}'} = sub { my $self = shift; sub { $self->send (@_) } }; # &{}
		1685	${'AnyEvent::CondVar::Base::()'} = 1; # fallback
		1686
		1687	our $WAITING;
1273		1688
1274	sub _send {	1689	sub _send {
1275	# nop	1690	# nop
1276	}	1691	}
1277		1692
…		…
1290	sub ready {	1705	sub ready {
1291	$_[0]{_ae_sent}	1706	$_[0]{_ae_sent}
1292	}	1707	}
1293		1708
1294	sub _wait {	1709	sub _wait {
		1710	$WAITING
		1711	and !$_[0]{_ae_sent}
		1712	and Carp::croak "AnyEvent::CondVar: recursive blocking wait detected";
		1713
		1714	local $WAITING = 1;
1295	AnyEvent->one_event while !$_[0]{_ae_sent};	1715	AnyEvent->one_event while !$_[0]{_ae_sent};
1296	}	1716	}
1297		1717
1298	sub recv {	1718	sub recv {
1299	$_[0]->_wait;	1719	$_[0]->_wait;
…		…
1301	Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak};	1721	Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak};
1302	wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0]	1722	wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0]
1303	}	1723	}
1304		1724
1305	sub cb {	1725	sub cb {
1306	$_[0]{_ae_cb} = $_[1] if @_ > 1;	1726	my $cv = shift;
		1727
		1728	@_
		1729	and $cv->{_ae_cb} = shift
		1730	and $cv->{_ae_sent}
		1731	and (delete $cv->{_ae_cb})->($cv);
		1732
1307	$_[0]{_ae_cb}	1733	$cv->{_ae_cb}
1308	}	1734	}
1309		1735
1310	sub begin {	1736	sub begin {
1311	++$_[0]{_ae_counter};	1737	++$_[0]{_ae_counter};
1312	$_[0]{_ae_end_cb} = $_[1] if @_ > 1;	1738	$_[0]{_ae_end_cb} = $_[1] if @_ > 1;
…		…
1361	C<PERL_ANYEVENT_MODEL>.	1787	C<PERL_ANYEVENT_MODEL>.
1362		1788
1363	When set to C<2> or higher, cause AnyEvent to report to STDERR which event	1789	When set to C<2> or higher, cause AnyEvent to report to STDERR which event
1364	model it chooses.	1790	model it chooses.
1365		1791
		1792	When set to C<8> or higher, then AnyEvent will report extra information on
		1793	which optional modules it loads and how it implements certain features.
		1794
1366	=item C<PERL_ANYEVENT_STRICT>	1795	=item C<PERL_ANYEVENT_STRICT>
1367		1796
1368	AnyEvent does not do much argument checking by default, as thorough	1797	AnyEvent does not do much argument checking by default, as thorough
1369	argument checking is very costly. Setting this variable to a true value	1798	argument checking is very costly. Setting this variable to a true value
1370	will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly	1799	will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly
1371	check the arguments passed to most method calls. If it finds any problems	1800	check the arguments passed to most method calls. If it finds any problems,
1372	it will croak.	1801	it will croak.
1373		1802
1374	In other words, enables "strict" mode.	1803	In other words, enables "strict" mode.
1375		1804
1376	Unlike C<use strict>, it is definitely recommended ot keep it off in	1805	Unlike C<use strict> (or it's modern cousin, C<< use L<common::sense>
1377	production. Keeping C<PERL_ANYEVENT_STRICT=1> in your environment while	1806	>>, it is definitely recommended to keep it off in production. Keeping
1378	developing programs can be very useful, however.	1807	C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs
		1808	can be very useful, however.
1379		1809
1380	=item C<PERL_ANYEVENT_MODEL>	1810	=item C<PERL_ANYEVENT_MODEL>
1381		1811
1382	This can be used to specify the event model to be used by AnyEvent, before	1812	This can be used to specify the event model to be used by AnyEvent, before
1383	auto detection and -probing kicks in. It must be a string consisting	1813	auto detection and -probing kicks in. It must be a string consisting
…		…
1426		1856
1427	=item C<PERL_ANYEVENT_MAX_FORKS>	1857	=item C<PERL_ANYEVENT_MAX_FORKS>
1428		1858
1429	The maximum number of child processes that C<AnyEvent::Util::fork_call>	1859	The maximum number of child processes that C<AnyEvent::Util::fork_call>
1430	will create in parallel.	1860	will create in parallel.
		1861
		1862	=item C<PERL_ANYEVENT_MAX_OUTSTANDING_DNS>
		1863
		1864	The default value for the C<max_outstanding> parameter for the default DNS
		1865	resolver - this is the maximum number of parallel DNS requests that are
		1866	sent to the DNS server.
		1867
		1868	=item C<PERL_ANYEVENT_RESOLV_CONF>
		1869
		1870	The file to use instead of F</etc/resolv.conf> (or OS-specific
		1871	configuration) in the default resolver. When set to the empty string, no
		1872	default config will be used.
		1873
		1874	=item C<PERL_ANYEVENT_CA_FILE>, C<PERL_ANYEVENT_CA_PATH>.
		1875
		1876	When neither C<ca_file> nor C<ca_path> was specified during
		1877	L<AnyEvent::TLS> context creation, and either of these environment
		1878	variables exist, they will be used to specify CA certificate locations
		1879	instead of a system-dependent default.
		1880
		1881	=item C<PERL_ANYEVENT_AVOID_GUARD> and C<PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT>
		1882
		1883	When these are set to C<1>, then the respective modules are not
		1884	loaded. Mostly good for testing AnyEvent itself.
1431		1885
1432	=back	1886	=back
1433		1887
1434	=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE	1888	=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE
1435		1889
…		…
1493	warn "read: $input\n"; # output what has been read	1947	warn "read: $input\n"; # output what has been read
1494	$cv->send if $input =~ /^q/i; # quit program if /^q/i	1948	$cv->send if $input =~ /^q/i; # quit program if /^q/i
1495	},	1949	},
1496	);	1950	);
1497		1951
1498	my $time_watcher; # can only be used once
1499
1500	sub new_timer {
1501	$timer = AnyEvent->timer (after => 1, cb => sub {	1952	my $time_watcher = AnyEvent->timer (after => 1, interval => 1, cb => sub {
1502	warn "timeout\n"; # print 'timeout' about every second	1953	warn "timeout\n"; # print 'timeout' at most every second
1503	&new_timer; # and restart the time
1504	});	1954	});
1505	}
1506
1507	new_timer; # create first timer
1508		1955
1509	$cv->recv; # wait until user enters /^q/i	1956	$cv->recv; # wait until user enters /^q/i
1510		1957
1511	=head1 REAL-WORLD EXAMPLE	1958	=head1 REAL-WORLD EXAMPLE
1512		1959
…		…
1643	through AnyEvent. The benchmark creates a lot of timers (with a zero	2090	through AnyEvent. The benchmark creates a lot of timers (with a zero
1644	timeout) and I/O watchers (watching STDOUT, a pty, to become writable,	2091	timeout) and I/O watchers (watching STDOUT, a pty, to become writable,
1645	which it is), lets them fire exactly once and destroys them again.	2092	which it is), lets them fire exactly once and destroys them again.
1646		2093
1647	Source code for this benchmark is found as F<eg/bench> in the AnyEvent	2094	Source code for this benchmark is found as F<eg/bench> in the AnyEvent
1648	distribution.	2095	distribution. It uses the L<AE> interface, which makes a real difference
		2096	for the EV and Perl backends only.
1649		2097
1650	=head3 Explanation of the columns	2098	=head3 Explanation of the columns
1651		2099
1652	I<watcher> is the number of event watchers created/destroyed. Since	2100	I<watcher> is the number of event watchers created/destroyed. Since
1653	different event models feature vastly different performances, each event	2101	different event models feature vastly different performances, each event
…		…
1674	watcher.	2122	watcher.
1675		2123
1676	=head3 Results	2124	=head3 Results
1677		2125
1678	name watchers bytes create invoke destroy comment	2126	name watchers bytes create invoke destroy comment
1679	EV/EV 400000 224 0.47 0.35 0.27 EV native interface	2127	EV/EV 100000 223 0.47 0.43 0.27 EV native interface
1680	EV/Any 100000 224 2.88 0.34 0.27 EV + AnyEvent watchers	2128	EV/Any 100000 223 0.48 0.42 0.26 EV + AnyEvent watchers
1681	CoroEV/Any 100000 224 2.85 0.35 0.28 coroutines + Coro::Signal	2129	Coro::EV/Any 100000 223 0.47 0.42 0.26 coroutines + Coro::Signal
1682	Perl/Any 100000 452 4.13 0.73 0.95 pure perl implementation	2130	Perl/Any 100000 431 2.70 0.74 0.92 pure perl implementation
1683	Event/Event 16000 517 32.20 31.80 0.81 Event native interface	2131	Event/Event 16000 516 31.16 31.84 0.82 Event native interface
1684	Event/Any 16000 590 35.85 31.55 1.06 Event + AnyEvent watchers	2132	Event/Any 16000 1203 42.61 34.79 1.80 Event + AnyEvent watchers
		2133	IOAsync/Any 16000 1911 41.92 27.45 16.81 via IO::Async::Loop::IO_Poll
		2134	IOAsync/Any 16000 1726 40.69 26.37 15.25 via IO::Async::Loop::Epoll
1685	Glib/Any 16000 1357 102.33 12.31 51.00 quadratic behaviour	2135	Glib/Any 16000 1118 89.00 12.57 51.17 quadratic behaviour
1686	Tk/Any 2000 1860 27.20 66.31 14.00 SEGV with >> 2000 watchers	2136	Tk/Any 2000 1346 20.96 10.75 8.00 SEGV with >> 2000 watchers
1687	POE/Event 2000 6328 109.99 751.67 14.02 via POE::Loop::Event	2137	POE/Any 2000 6951 108.97 795.32 14.24 via POE::Loop::Event
1688	POE/Select 2000 6027 94.54 809.13 579.80 via POE::Loop::Select	2138	POE/Any 2000 6648 94.79 774.40 575.51 via POE::Loop::Select
1689		2139
1690	=head3 Discussion	2140	=head3 Discussion
1691		2141
1692	The benchmark does I<not> measure scalability of the event loop very	2142	The benchmark does I<not> measure scalability of the event loop very
1693	well. For example, a select-based event loop (such as the pure perl one)	2143	well. For example, a select-based event loop (such as the pure perl one)
…		…
1705	benchmark machine, handling an event takes roughly 1600 CPU cycles with	2155	benchmark machine, handling an event takes roughly 1600 CPU cycles with
1706	EV, 3100 CPU cycles with AnyEvent's pure perl loop and almost 3000000 CPU	2156	EV, 3100 CPU cycles with AnyEvent's pure perl loop and almost 3000000 CPU
1707	cycles with POE.	2157	cycles with POE.
1708		2158
1709	C<EV> is the sole leader regarding speed and memory use, which are both	2159	C<EV> is the sole leader regarding speed and memory use, which are both
1710	maximal/minimal, respectively. Even when going through AnyEvent, it uses	2160	maximal/minimal, respectively. When using the L<AE> API there is zero
		2161	overhead (when going through the AnyEvent API create is about 5-6 times
		2162	slower, with other times being equal, so still uses far less memory than
1711	far less memory than any other event loop and is still faster than Event	2163	any other event loop and is still faster than Event natively).
1712	natively.
1713		2164
1714	The pure perl implementation is hit in a few sweet spots (both the	2165	The pure perl implementation is hit in a few sweet spots (both the
1715	constant timeout and the use of a single fd hit optimisations in the perl	2166	constant timeout and the use of a single fd hit optimisations in the perl
1716	interpreter and the backend itself). Nevertheless this shows that it	2167	interpreter and the backend itself). Nevertheless this shows that it
1717	adds very little overhead in itself. Like any select-based backend its	2168	adds very little overhead in itself. Like any select-based backend its
1718	performance becomes really bad with lots of file descriptors (and few of	2169	performance becomes really bad with lots of file descriptors (and few of
1719	them active), of course, but this was not subject of this benchmark.	2170	them active), of course, but this was not subject of this benchmark.
1720		2171
1721	The C<Event> module has a relatively high setup and callback invocation	2172	The C<Event> module has a relatively high setup and callback invocation
1722	cost, but overall scores in on the third place.	2173	cost, but overall scores in on the third place.
		2174
		2175	C<IO::Async> performs admirably well, about on par with C<Event>, even
		2176	when using its pure perl backend.
1723		2177
1724	C<Glib>'s memory usage is quite a bit higher, but it features a	2178	C<Glib>'s memory usage is quite a bit higher, but it features a
1725	faster callback invocation and overall ends up in the same class as	2179	faster callback invocation and overall ends up in the same class as
1726	C<Event>. However, Glib scales extremely badly, doubling the number of	2180	C<Event>. However, Glib scales extremely badly, doubling the number of
1727	watchers increases the processing time by more than a factor of four,	2181	watchers increases the processing time by more than a factor of four,
…		…
1788	In this benchmark, we use 10000 socket pairs (20000 sockets), of which 100	2242	In this benchmark, we use 10000 socket pairs (20000 sockets), of which 100
1789	(1%) are active. This mirrors the activity of large servers with many	2243	(1%) are active. This mirrors the activity of large servers with many
1790	connections, most of which are idle at any one point in time.	2244	connections, most of which are idle at any one point in time.
1791		2245
1792	Source code for this benchmark is found as F<eg/bench2> in the AnyEvent	2246	Source code for this benchmark is found as F<eg/bench2> in the AnyEvent
1793	distribution.	2247	distribution. It uses the L<AE> interface, which makes a real difference
		2248	for the EV and Perl backends only.
1794		2249
1795	=head3 Explanation of the columns	2250	=head3 Explanation of the columns
1796		2251
1797	I<sockets> is the number of sockets, and twice the number of "servers" (as	2252	I<sockets> is the number of sockets, and twice the number of "servers" (as
1798	each server has a read and write socket end).	2253	each server has a read and write socket end).
…		…
1805	it to another server. This includes deleting the old timeout and creating	2260	it to another server. This includes deleting the old timeout and creating
1806	a new one that moves the timeout into the future.	2261	a new one that moves the timeout into the future.
1807		2262
1808	=head3 Results	2263	=head3 Results
1809		2264
1810	name sockets create request	2265	name sockets create request
1811	EV 20000 69.01 11.16	2266	EV 20000 62.66 7.99
1812	Perl 20000 73.32 35.87	2267	Perl 20000 68.32 32.64
1813	Event 20000 212.62 257.32	2268	IOAsync 20000 174.06 101.15 epoll
1814	Glib 20000 651.16 1896.30	2269	IOAsync 20000 174.67 610.84 poll
		2270	Event 20000 202.69 242.91
		2271	Glib 20000 557.01 1689.52
1815	POE 20000 349.67 12317.24 uses POE::Loop::Event	2272	POE 20000 341.54 12086.32 uses POE::Loop::Event
1816		2273
1817	=head3 Discussion	2274	=head3 Discussion
1818		2275
1819	This benchmark I<does> measure scalability and overall performance of the	2276	This benchmark I<does> measure scalability and overall performance of the
1820	particular event loop.	2277	particular event loop.
…		…
1822	EV is again fastest. Since it is using epoll on my system, the setup time	2279	EV is again fastest. Since it is using epoll on my system, the setup time
1823	is relatively high, though.	2280	is relatively high, though.
1824		2281
1825	Perl surprisingly comes second. It is much faster than the C-based event	2282	Perl surprisingly comes second. It is much faster than the C-based event
1826	loops Event and Glib.	2283	loops Event and Glib.
		2284
		2285	IO::Async performs very well when using its epoll backend, and still quite
		2286	good compared to Glib when using its pure perl backend.
1827		2287
1828	Event suffers from high setup time as well (look at its code and you will	2288	Event suffers from high setup time as well (look at its code and you will
1829	understand why). Callback invocation also has a high overhead compared to	2289	understand why). Callback invocation also has a high overhead compared to
1830	the C<< $_->() for .. >>-style loop that the Perl event loop uses. Event	2290	the C<< $_->() for .. >>-style loop that the Perl event loop uses. Event
1831	uses select or poll in basically all documented configurations.	2291	uses select or poll in basically all documented configurations.
…		…
1900		2360
1901	Recently I was told about the benchmark in the IO::Lambda manpage, which	2361	Recently I was told about the benchmark in the IO::Lambda manpage, which
1902	could be misinterpreted to make AnyEvent look bad. In fact, the benchmark	2362	could be misinterpreted to make AnyEvent look bad. In fact, the benchmark
1903	simply compares IO::Lambda with POE, and IO::Lambda looks better (which	2363	simply compares IO::Lambda with POE, and IO::Lambda looks better (which
1904	shouldn't come as a surprise to anybody). As such, the benchmark is	2364	shouldn't come as a surprise to anybody). As such, the benchmark is
1905	fine, and shows that the AnyEvent backend from IO::Lambda isn't very	2365	fine, and mostly shows that the AnyEvent backend from IO::Lambda isn't
1906	optimal. But how would AnyEvent compare when used without the extra	2366	very optimal. But how would AnyEvent compare when used without the extra
1907	baggage? To explore this, I wrote the equivalent benchmark for AnyEvent.	2367	baggage? To explore this, I wrote the equivalent benchmark for AnyEvent.
1908		2368
1909	The benchmark itself creates an echo-server, and then, for 500 times,	2369	The benchmark itself creates an echo-server, and then, for 500 times,
1910	connects to the echo server, sends a line, waits for the reply, and then	2370	connects to the echo server, sends a line, waits for the reply, and then
1911	creates the next connection. This is a rather bad benchmark, as it doesn't	2371	creates the next connection. This is a rather bad benchmark, as it doesn't
1912	test the efficiency of the framework, but it is a benchmark nevertheless.	2372	test the efficiency of the framework or much non-blocking I/O, but it is a
		2373	benchmark nevertheless.
1913		2374
1914	name runtime	2375	name runtime
1915	Lambda/select 0.330 sec	2376	Lambda/select 0.330 sec
1916	+ optimized 0.122 sec	2377	+ optimized 0.122 sec
1917	Lambda/AnyEvent 0.327 sec	2378	Lambda/AnyEvent 0.327 sec
…		…
1923		2384
1924	AnyEvent/select/nb 0.085 sec	2385	AnyEvent/select/nb 0.085 sec
1925	AnyEvent/EV/nb 0.068 sec	2386	AnyEvent/EV/nb 0.068 sec
1926	+state machine 0.134 sec	2387	+state machine 0.134 sec
1927		2388
1928	The benchmark is also a bit unfair (my fault) - the IO::Lambda	2389	The benchmark is also a bit unfair (my fault): the IO::Lambda/POE
1929	benchmarks actually make blocking connects and use 100% blocking I/O,	2390	benchmarks actually make blocking connects and use 100% blocking I/O,
1930	defeating the purpose of an event-based solution. All of the newly	2391	defeating the purpose of an event-based solution. All of the newly
1931	written AnyEvent benchmarks use 100% non-blocking connects (using	2392	written AnyEvent benchmarks use 100% non-blocking connects (using
1932	AnyEvent::Socket::tcp_connect and the asynchronous pure perl DNS	2393	AnyEvent::Socket::tcp_connect and the asynchronous pure perl DNS
1933	resolver), so AnyEvent is at a disadvantage here as non-blocking connects	2394	resolver), so AnyEvent is at a disadvantage here, as non-blocking connects
1934	generally require a lot more bookkeeping and event handling than blocking	2395	generally require a lot more bookkeeping and event handling than blocking
1935	connects (which involve a single syscall only).	2396	connects (which involve a single syscall only).
1936		2397
1937	The last AnyEvent benchmark additionally uses L<AnyEvent::Handle>, which	2398	The last AnyEvent benchmark additionally uses L<AnyEvent::Handle>, which
1938	offers similar expressive power as POE and IO::Lambda (using conventional	2399	offers similar expressive power as POE and IO::Lambda, using conventional
1939	Perl syntax), which means both the echo server and the client are 100%	2400	Perl syntax. This means that both the echo server and the client are 100%
1940	non-blocking w.r.t. I/O, further placing it at a disadvantage.	2401	non-blocking, further placing it at a disadvantage.
1941		2402
1942	As you can see, AnyEvent + EV even beats the hand-optimised "raw sockets	2403	As you can see, the AnyEvent + EV combination even beats the
1943	benchmark", while AnyEvent + its pure perl backend easily beats	2404	hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl
1944	IO::Lambda and POE.	2405	backend easily beats IO::Lambda and POE.
1945		2406
1946	And even the 100% non-blocking version written using the high-level (and	2407	And even the 100% non-blocking version written using the high-level (and
1947	slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda,	2408	slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda
		2409	higher level ("unoptimised") abstractions by a large margin, even though
1948	even thought it does all of DNS, tcp-connect and socket I/O in a	2410	it does all of DNS, tcp-connect and socket I/O in a non-blocking way.
1949	non-blocking way.
1950		2411
1951	The two AnyEvent benchmarks can be found as F<eg/ae0.pl> and F<eg/ae2.pl>	2412	The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and
1952	in the AnyEvent distribution, the remaining benchmarks are part of the	2413	F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are
1953	IO::lambda distribution and were used without any changes.	2414	part of the IO::Lambda distribution and were used without any changes.
1954		2415
1955		2416
1956	=head1 SIGNALS	2417	=head1 SIGNALS
1957		2418
1958	AnyEvent currently installs handlers for these signals:	2419	AnyEvent currently installs handlers for these signals:
…		…
1962	=item SIGCHLD	2423	=item SIGCHLD
1963		2424
1964	A handler for C<SIGCHLD> is installed by AnyEvent's child watcher	2425	A handler for C<SIGCHLD> is installed by AnyEvent's child watcher
1965	emulation for event loops that do not support them natively. Also, some	2426	emulation for event loops that do not support them natively. Also, some
1966	event loops install a similar handler.	2427	event loops install a similar handler.
		2428
		2429	Additionally, when AnyEvent is loaded and SIGCHLD is set to IGNORE, then
		2430	AnyEvent will reset it to default, to avoid losing child exit statuses.
1967		2431
1968	=item SIGPIPE	2432	=item SIGPIPE
1969		2433
1970	A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef>	2434	A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef>
1971	when AnyEvent gets loaded.	2435	when AnyEvent gets loaded.
…		…
1983		2447
1984	=back	2448	=back
1985		2449
1986	=cut	2450	=cut
1987		2451
		2452	undef $SIG{CHLD}
		2453	if $SIG{CHLD} eq 'IGNORE';
		2454
1988	$SIG{PIPE} = sub { }	2455	$SIG{PIPE} = sub { }
1989	unless defined $SIG{PIPE};	2456	unless defined $SIG{PIPE};
		2457
		2458	=head1 RECOMMENDED/OPTIONAL MODULES
		2459
		2460	One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and
		2461	it's built-in modules) are required to use it.
		2462
		2463	That does not mean that AnyEvent won't take advantage of some additional
		2464	modules if they are installed.
		2465
		2466	This section explains which additional modules will be used, and how they
		2467	affect AnyEvent's operation.
		2468
		2469	=over 4
		2470
		2471	=item L<Async::Interrupt>
		2472
		2473	This slightly arcane module is used to implement fast signal handling: To
		2474	my knowledge, there is no way to do completely race-free and quick
		2475	signal handling in pure perl. To ensure that signals still get
		2476	delivered, AnyEvent will start an interval timer to wake up perl (and
		2477	catch the signals) with some delay (default is 10 seconds, look for
		2478	C<$AnyEvent::MAX_SIGNAL_LATENCY>).
		2479
		2480	If this module is available, then it will be used to implement signal
		2481	catching, which means that signals will not be delayed, and the event loop
		2482	will not be interrupted regularly, which is more efficient (and good for
		2483	battery life on laptops).
		2484
		2485	This affects not just the pure-perl event loop, but also other event loops
		2486	that have no signal handling on their own (e.g. Glib, Tk, Qt).
		2487
		2488	Some event loops (POE, Event, Event::Lib) offer signal watchers natively,
		2489	and either employ their own workarounds (POE) or use AnyEvent's workaround
		2490	(using C<$AnyEvent::MAX_SIGNAL_LATENCY>). Installing L<Async::Interrupt>
		2491	does nothing for those backends.
		2492
		2493	=item L<EV>
		2494
		2495	This module isn't really "optional", as it is simply one of the backend
		2496	event loops that AnyEvent can use. However, it is simply the best event
		2497	loop available in terms of features, speed and stability: It supports
		2498	the AnyEvent API optimally, implements all the watcher types in XS, does
		2499	automatic timer adjustments even when no monotonic clock is available,
		2500	can take avdantage of advanced kernel interfaces such as C<epoll> and
		2501	C<kqueue>, and is the fastest backend I<by far>. You can even embed
		2502	L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>).
		2503
		2504	=item L<Guard>
		2505
		2506	The guard module, when used, will be used to implement
		2507	C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a
		2508	lot less memory), but otherwise doesn't affect guard operation much. It is
		2509	purely used for performance.
		2510
		2511	=item L<JSON> and L<JSON::XS>
		2512
		2513	One of these modules is required when you want to read or write JSON data
		2514	via L<AnyEvent::Handle>. It is also written in pure-perl, but can take
		2515	advantage of the ultra-high-speed L<JSON::XS> module when it is installed.
		2516
		2517	In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is
		2518	installed.
		2519
		2520	=item L<Net::SSLeay>
		2521
		2522	Implementing TLS/SSL in Perl is certainly interesting, but not very
		2523	worthwhile: If this module is installed, then L<AnyEvent::Handle> (with
		2524	the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL.
		2525
		2526	=item L<Time::HiRes>
		2527
		2528	This module is part of perl since release 5.008. It will be used when the
		2529	chosen event library does not come with a timing source on it's own. The
		2530	pure-perl event loop (L<AnyEvent::Impl::Perl>) will additionally use it to
		2531	try to use a monotonic clock for timing stability.
		2532
		2533	=back
1990		2534
1991		2535
1992	=head1 FORK	2536	=head1 FORK
1993		2537
1994	Most event libraries are not fork-safe. The ones who are usually are	2538	Most event libraries are not fork-safe. The ones who are usually are
1995	because they rely on inefficient but fork-safe C<select> or C<poll>	2539	because they rely on inefficient but fork-safe C<select> or C<poll>
1996	calls. Only L<EV> is fully fork-aware.	2540	calls. Only L<EV> is fully fork-aware.
1997		2541
		2542	This means that, in general, you cannot fork and do event processing
		2543	in the child if a watcher was created before the fork (which in turn
		2544	initialises the event library).
		2545
1998	If you have to fork, you must either do so I<before> creating your first	2546	If you have to fork, you must either do so I<before> creating your first
1999	watcher OR you must not use AnyEvent at all in the child.	2547	watcher OR you must not use AnyEvent at all in the child OR you must do
		2548	something completely out of the scope of AnyEvent.
		2549
		2550	The problem of doing event processing in the parent I<and> the child
		2551	is much more complicated: even for backends that I<are> fork-aware or
		2552	fork-safe, their behaviour is not usually what you want: fork clones all
		2553	watchers, that means all timers, I/O watchers etc. are active in both
		2554	parent and child, which is almost never what you want.
2000		2555
2001		2556
2002	=head1 SECURITY CONSIDERATIONS	2557	=head1 SECURITY CONSIDERATIONS
2003		2558
2004	AnyEvent can be forced to load any event model via	2559	AnyEvent can be forced to load any event model via
…		…
2018	Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can	2573	Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can
2019	be used to probe what backend is used and gain other information (which is	2574	be used to probe what backend is used and gain other information (which is
2020	probably even less useful to an attacker than PERL_ANYEVENT_MODEL), and	2575	probably even less useful to an attacker than PERL_ANYEVENT_MODEL), and
2021	$ENV{PERL_ANYEVENT_STRICT}.	2576	$ENV{PERL_ANYEVENT_STRICT}.
2022		2577
		2578	Note that AnyEvent will remove I<all> environment variables starting with
		2579	C<PERL_ANYEVENT_> from C<%ENV> when it is loaded while taint mode is
		2580	enabled.
		2581
2023		2582
2024	=head1 BUGS	2583	=head1 BUGS
2025		2584
2026	Perl 5.8 has numerous memleaks that sometimes hit this module and are hard	2585	Perl 5.8 has numerous memleaks that sometimes hit this module and are hard
2027	to work around. If you suffer from memleaks, first upgrade to Perl 5.10	2586	to work around. If you suffer from memleaks, first upgrade to Perl 5.10
…		…
2038	L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.	2597	L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.
2039		2598
2040	Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,	2599	Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,
2041	L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,	2600	L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,
2042	L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,	2601	L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,
2043	L<AnyEvent::Impl::POE>.	2602	L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>.
2044		2603
2045	Non-blocking file handles, sockets, TCP clients and	2604	Non-blocking file handles, sockets, TCP clients and
2046	servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>.	2605	servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.
2047		2606
2048	Asynchronous DNS: L<AnyEvent::DNS>.	2607	Asynchronous DNS: L<AnyEvent::DNS>.
2049		2608
2050	Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>,	2609	Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>,
		2610	L<Coro::Event>,
2051		2611
2052	Nontrivial usage examples: L<Net::FCP>, L<Net::XMPP2>, L<AnyEvent::DNS>.	2612	Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::XMPP>,
		2613	L<AnyEvent::HTTP>.
2053		2614
2054		2615
2055	=head1 AUTHOR	2616	=head1 AUTHOR
2056		2617
2057	Marc Lehmann <schmorp@schmorp.de>	2618	Marc Lehmann <schmorp@schmorp.de>

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