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Comparing AnyEvent/README (file contents):
Revision 1.28 by root, Sat Jul 12 20:45:27 2008 UTC vs.
Revision 1.56 by root, Thu Nov 19 01:55:57 2009 UTC

…		…
1	NAME	1	NAME
2	AnyEvent - provide framework for multiple event loops	2	AnyEvent - the DBI of event loop programming
3		3
4	EV, Event, Glib, Tk, Perl, Event::Lib, Qt, POE - various supported event	4	EV, Event, Glib, Tk, Perl, Event::Lib, Irssi, rxvt-unicode, IO::Async,
5	loops	5	Qt and POE are various supported event loops/environments.
6		6
7	SYNOPSIS	7	SYNOPSIS
8	use AnyEvent;	8	use AnyEvent;
9		9
		10	# file descriptor readable
10	my $w = AnyEvent->io (fh => $fh, poll => "r\|w", cb => sub {	11	my $w = AnyEvent->io (fh => $fh, poll => "r", cb => sub { ... });
		12
		13	# one-shot or repeating timers
		14	my $w = AnyEvent->timer (after => $seconds, cb => sub { ... });
		15	my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ...
		16
		17	print AnyEvent->now; # prints current event loop time
		18	print AnyEvent->time; # think Time::HiRes::time or simply CORE::time.
		19
		20	# POSIX signal
		21	my $w = AnyEvent->signal (signal => "TERM", cb => sub { ... });
		22
		23	# child process exit
		24	my $w = AnyEvent->child (pid => $pid, cb => sub {
		25	my ($pid, $status) = @_;
11	...	26	...
12	});	27	});
13		28
14	my $w = AnyEvent->timer (after => $seconds, cb => sub {	29	# called when event loop idle (if applicable)
15	...	30	my $w = AnyEvent->idle (cb => sub { ... });
16	});
17		31
18	my $w = AnyEvent->condvar; # stores whether a condition was flagged	32	my $w = AnyEvent->condvar; # stores whether a condition was flagged
19	$w->send; # wake up current and all future recv's	33	$w->send; # wake up current and all future recv's
20	$w->recv; # enters "main loop" till $condvar gets ->send	34	$w->recv; # enters "main loop" till $condvar gets ->send
		35	# use a condvar in callback mode:
		36	$w->cb (sub { $_[0]->recv });
21		37
22	INTRODUCTION/TUTORIAL	38	INTRODUCTION/TUTORIAL
23	This manpage is mainly a reference manual. If you are interested in a	39	This manpage is mainly a reference manual. If you are interested in a
24	tutorial or some gentle introduction, have a look at the AnyEvent::Intro	40	tutorial or some gentle introduction, have a look at the AnyEvent::Intro
25	manpage.	41	manpage.
		42
		43	SUPPORT
		44	There is a mailinglist for discussing all things AnyEvent, and an IRC
		45	channel, too.
		46
		47	See the AnyEvent project page at the Schmorpforge Ta-Sa Software
		48	Repository, at <http://anyevent.schmorp.de>, for more info.
26		49
27	WHY YOU SHOULD USE THIS MODULE (OR NOT)	50	WHY YOU SHOULD USE THIS MODULE (OR NOT)
28	Glib, POE, IO::Async, Event... CPAN offers event models by the dozen	51	Glib, POE, IO::Async, Event... CPAN offers event models by the dozen
29	nowadays. So what is different about AnyEvent?	52	nowadays. So what is different about AnyEvent?
30		53
123	These watchers are normal Perl objects with normal Perl lifetime. After	146	These watchers are normal Perl objects with normal Perl lifetime. After
124	creating a watcher it will immediately "watch" for events and invoke the	147	creating a watcher it will immediately "watch" for events and invoke the
125	callback when the event occurs (of course, only when the event model is	148	callback when the event occurs (of course, only when the event model is
126	in control).	149	in control).
127		150
		151	Note that callbacks must not permanently change global variables
		152	potentially in use by the event loop (such as $_ or $[) and that
		153	callbacks must not "die". The former is good programming practise in
		154	Perl and the latter stems from the fact that exception handling differs
		155	widely between event loops.
		156
128	To disable the watcher you have to destroy it (e.g. by setting the	157	To disable the watcher you have to destroy it (e.g. by setting the
129	variable you store it in to "undef" or otherwise deleting all references	158	variable you store it in to "undef" or otherwise deleting all references
130	to it).	159	to it).
131		160
132	All watchers are created by calling a method on the "AnyEvent" class.	161	All watchers are created by calling a method on the "AnyEvent" class.
…		…
144	Note that "my $w; $w =" combination. This is necessary because in Perl,	173	Note that "my $w; $w =" combination. This is necessary because in Perl,
145	my variables are only visible after the statement in which they are	174	my variables are only visible after the statement in which they are
146	declared.	175	declared.
147		176
148	I/O WATCHERS	177	I/O WATCHERS
		178	$w = AnyEvent->io (
		179	fh => <filehandle_or_fileno>,
		180	poll => <"r" or "w">,
		181	cb => <callback>,
		182	);
		183
149	You can create an I/O watcher by calling the "AnyEvent->io" method with	184	You can create an I/O watcher by calling the "AnyEvent->io" method with
150	the following mandatory key-value pairs as arguments:	185	the following mandatory key-value pairs as arguments:
151		186
152	"fh" the Perl file handle (not file descriptor) to watch for events	187	"fh" is the Perl file handle (or a naked file descriptor) to watch for
153	(AnyEvent might or might not keep a reference to this file handle).	188	events (AnyEvent might or might not keep a reference to this file
		189	handle). Note that only file handles pointing to things for which
		190	non-blocking operation makes sense are allowed. This includes sockets,
		191	most character devices, pipes, fifos and so on, but not for example
		192	files or block devices.
		193
154	"poll" must be a string that is either "r" or "w", which creates a	194	"poll" must be a string that is either "r" or "w", which creates a
155	watcher waiting for "r"eadable or "w"ritable events, respectively. "cb"	195	watcher waiting for "r"eadable or "w"ritable events, respectively.
		196
156	is the callback to invoke each time the file handle becomes ready.	197	"cb" is the callback to invoke each time the file handle becomes ready.
157		198
158	Although the callback might get passed parameters, their value and	199	Although the callback might get passed parameters, their value and
159	presence is undefined and you cannot rely on them. Portable AnyEvent	200	presence is undefined and you cannot rely on them. Portable AnyEvent
160	callbacks cannot use arguments passed to I/O watcher callbacks.	201	callbacks cannot use arguments passed to I/O watcher callbacks.
161		202
…		…
175	warn "read: $input\n";	216	warn "read: $input\n";
176	undef $w;	217	undef $w;
177	});	218	});
178		219
179	TIME WATCHERS	220	TIME WATCHERS
		221	$w = AnyEvent->timer (after => <seconds>, cb => <callback>);
		222
		223	$w = AnyEvent->timer (
		224	after => <fractional_seconds>,
		225	interval => <fractional_seconds>,
		226	cb => <callback>,
		227	);
		228
180	You can create a time watcher by calling the "AnyEvent->timer" method	229	You can create a time watcher by calling the "AnyEvent->timer" method
181	with the following mandatory arguments:	230	with the following mandatory arguments:
182		231
183	"after" specifies after how many seconds (fractional values are	232	"after" specifies after how many seconds (fractional values are
184	supported) the callback should be invoked. "cb" is the callback to	233	supported) the callback should be invoked. "cb" is the callback to
…		…
293	In either case, if you care (and in most cases, you don't), then you	342	In either case, if you care (and in most cases, you don't), then you
294	can get whatever behaviour you want with any event loop, by taking	343	can get whatever behaviour you want with any event loop, by taking
295	the difference between "AnyEvent->time" and "AnyEvent->now" into	344	the difference between "AnyEvent->time" and "AnyEvent->now" into
296	account.	345	account.
297		346
		347	AnyEvent->now_update
		348	Some event loops (such as EV or AnyEvent::Impl::Perl) cache the
		349	current time for each loop iteration (see the discussion of
		350	AnyEvent->now, above).
		351
		352	When a callback runs for a long time (or when the process sleeps),
		353	then this "current" time will differ substantially from the real
		354	time, which might affect timers and time-outs.
		355
		356	When this is the case, you can call this method, which will update
		357	the event loop's idea of "current time".
		358
		359	A typical example would be a script in a web server (e.g.
		360	"mod_perl") - when mod_perl executes the script, then the event loop
		361	will have the wrong idea about the "current time" (being potentially
		362	far in the past, when the script ran the last time). In that case
		363	you should arrange a call to "AnyEvent->now_update" each time the
		364	web server process wakes up again (e.g. at the start of your script,
		365	or in a handler).
		366
		367	Note that updating the time might cause some events to be handled.
		368
298	SIGNAL WATCHERS	369	SIGNAL WATCHERS
		370	$w = AnyEvent->signal (signal => <uppercase_signal_name>, cb => <callback>);
		371
299	You can watch for signals using a signal watcher, "signal" is the signal	372	You can watch for signals using a signal watcher, "signal" is the signal
300	name in uppercase and without any "SIG" prefix, "cb" is the Perl	373	name in uppercase and without any "SIG" prefix, "cb" is the Perl
301	callback to be invoked whenever a signal occurs.	374	callback to be invoked whenever a signal occurs.
302		375
303	Although the callback might get passed parameters, their value and	376	Although the callback might get passed parameters, their value and
…		…
308	invocation, and callback invocation will be synchronous. Synchronous	381	invocation, and callback invocation will be synchronous. Synchronous
309	means that it might take a while until the signal gets handled by the	382	means that it might take a while until the signal gets handled by the
310	process, but it is guaranteed not to interrupt any other callbacks.	383	process, but it is guaranteed not to interrupt any other callbacks.
311		384
312	The main advantage of using these watchers is that you can share a	385	The main advantage of using these watchers is that you can share a
313	signal between multiple watchers.	386	signal between multiple watchers, and AnyEvent will ensure that signals
		387	will not interrupt your program at bad times.
314		388
315	This watcher might use %SIG, so programs overwriting those signals	389	This watcher might use %SIG (depending on the event loop used), so
316	directly will likely not work correctly.	390	programs overwriting those signals directly will likely not work
		391	correctly.
317		392
318	Example: exit on SIGINT	393	Example: exit on SIGINT
319		394
320	my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });	395	my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
321		396
		397	Signal Races, Delays and Workarounds
		398	Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching
		399	callbacks to signals in a generic way, which is a pity, as you cannot do
		400	race-free signal handling in perl, requiring C libraries for this.
		401	AnyEvent will try to do it's best, which means in some cases, signals
		402	will be delayed. The maximum time a signal might be delayed is specified
		403	in $AnyEvent::MAX_SIGNAL_LATENCY (default: 10 seconds). This variable
		404	can be changed only before the first signal watcher is created, and
		405	should be left alone otherwise. This variable determines how often
		406	AnyEvent polls for signals (in case a wake-up was missed). Higher values
		407	will cause fewer spurious wake-ups, which is better for power and CPU
		408	saving.
		409
		410	All these problems can be avoided by installing the optional
		411	Async::Interrupt module, which works with most event loops. It will not
		412	work with inherently broken event loops such as Event or Event::Lib (and
		413	not with POE currently, as POE does it's own workaround with one-second
		414	latency). For those, you just have to suffer the delays.
		415
322	CHILD PROCESS WATCHERS	416	CHILD PROCESS WATCHERS
		417	$w = AnyEvent->child (pid => <process id>, cb => <callback>);
		418
323	You can also watch on a child process exit and catch its exit status.	419	You can also watch on a child process exit and catch its exit status.
324		420
325	The child process is specified by the "pid" argument (if set to 0, it	421	The child process is specified by the "pid" argument (one some backends,
326	watches for any child process exit). The watcher will trigger as often	422	using 0 watches for any child process exit, on others this will croak).
327	as status change for the child are received. This works by installing a	423	The watcher will be triggered only when the child process has finished
328	signal handler for "SIGCHLD". The callback will be called with the pid	424	and an exit status is available, not on any trace events
329	and exit status (as returned by waitpid), so unlike other watcher types,	425	(stopped/continued).
330	you can rely on child watcher callback arguments.	426
		427	The callback will be called with the pid and exit status (as returned by
		428	waitpid), so unlike other watcher types, you can rely on child watcher
		429	callback arguments.
		430
		431	This watcher type works by installing a signal handler for "SIGCHLD",
		432	and since it cannot be shared, nothing else should use SIGCHLD or reap
		433	random child processes (waiting for specific child processes, e.g.
		434	inside "system", is just fine).
331		435
332	There is a slight catch to child watchers, however: you usually start	436	There is a slight catch to child watchers, however: you usually start
333	them after the child process was created, and this means the process	437	them after the child process was created, and this means the process
334	could have exited already (and no SIGCHLD will be sent anymore).	438	could have exited already (and no SIGCHLD will be sent anymore).
335		439
336	Not all event models handle this correctly (POE doesn't), but even for	440	Not all event models handle this correctly (neither POE nor IO::Async
		441	do, see their AnyEvent::Impl manpages for details), but even for event
337	event models that do handle this correctly, they usually need to be	442	models that do handle this correctly, they usually need to be loaded
338	loaded before the process exits (i.e. before you fork in the first	443	before the process exits (i.e. before you fork in the first place).
339	place).	444	AnyEvent's pure perl event loop handles all cases correctly regardless
		445	of when you start the watcher.
340		446
341	This means you cannot create a child watcher as the very first thing in	447	This means you cannot create a child watcher as the very first thing in
342	an AnyEvent program, you have to create at least one watcher before	448	an AnyEvent program, you have to create at least one watcher before
343	you "fork" the child (alternatively, you can call "AnyEvent::detect").	449	you "fork" the child (alternatively, you can call "AnyEvent::detect").
344		450
		451	As most event loops do not support waiting for child events, they will
		452	be emulated by AnyEvent in most cases, in which the latency and race
		453	problems mentioned in the description of signal watchers apply.
		454
345	Example: fork a process and wait for it	455	Example: fork a process and wait for it
346		456
347	my $done = AnyEvent->condvar;	457	my $done = AnyEvent->condvar;
348		458
349	my $pid = fork or exit 5;	459	my $pid = fork or exit 5;
350		460
351	my $w = AnyEvent->child (	461	my $w = AnyEvent->child (
352	pid => $pid,	462	pid => $pid,
353	cb => sub {	463	cb => sub {
354	my ($pid, $status) = @_;	464	my ($pid, $status) = @_;
355	warn "pid $pid exited with status $status";	465	warn "pid $pid exited with status $status";
356	$done->send;	466	$done->send;
357	},	467	},
358	);	468	);
359		469
360	# do something else, then wait for process exit	470	# do something else, then wait for process exit
361	$done->recv;	471	$done->recv;
362		472
		473	IDLE WATCHERS
		474	$w = AnyEvent->idle (cb => <callback>);
		475
		476	Sometimes there is a need to do something, but it is not so important to
		477	do it instantly, but only when there is nothing better to do. This
		478	"nothing better to do" is usually defined to be "no other events need
		479	attention by the event loop".
		480
		481	Idle watchers ideally get invoked when the event loop has nothing better
		482	to do, just before it would block the process to wait for new events.
		483	Instead of blocking, the idle watcher is invoked.
		484
		485	Most event loops unfortunately do not really support idle watchers (only
		486	EV, Event and Glib do it in a usable fashion) - for the rest, AnyEvent
		487	will simply call the callback "from time to time".
		488
		489	Example: read lines from STDIN, but only process them when the program
		490	is otherwise idle:
		491
		492	my @lines; # read data
		493	my $idle_w;
		494	my $io_w = AnyEvent->io (fh => \*STDIN, poll => 'r', cb => sub {
		495	push @lines, scalar <STDIN>;
		496
		497	# start an idle watcher, if not already done
		498	$idle_w \|\|= AnyEvent->idle (cb => sub {
		499	# handle only one line, when there are lines left
		500	if (my $line = shift @lines) {
		501	print "handled when idle: $line";
		502	} else {
		503	# otherwise disable the idle watcher again
		504	undef $idle_w;
		505	}
		506	});
		507	});
		508
363	CONDITION VARIABLES	509	CONDITION VARIABLES
		510	$cv = AnyEvent->condvar;
		511
		512	$cv->send (<list>);
		513	my @res = $cv->recv;
		514
364	If you are familiar with some event loops you will know that all of them	515	If you are familiar with some event loops you will know that all of them
365	require you to run some blocking "loop", "run" or similar function that	516	require you to run some blocking "loop", "run" or similar function that
366	will actively watch for new events and call your callbacks.	517	will actively watch for new events and call your callbacks.
367		518
368	AnyEvent is different, it expects somebody else to run the event loop	519	AnyEvent is slightly different: it expects somebody else to run the
369	and will only block when necessary (usually when told by the user).	520	event loop and will only block when necessary (usually when told by the
		521	user).
370		522
371	The instrument to do that is called a "condition variable", so called	523	The instrument to do that is called a "condition variable", so called
372	because they represent a condition that must become true.	524	because they represent a condition that must become true.
		525
		526	Now is probably a good time to look at the examples further below.
373		527
374	Condition variables can be created by calling the "AnyEvent->condvar"	528	Condition variables can be created by calling the "AnyEvent->condvar"
375	method, usually without arguments. The only argument pair allowed is	529	method, usually without arguments. The only argument pair allowed is
376	"cb", which specifies a callback to be called when the condition	530	"cb", which specifies a callback to be called when the condition
377	variable becomes true.	531	variable becomes true, with the condition variable as the first argument
		532	(but not the results).
378		533
379	After creation, the condition variable is "false" until it becomes	534	After creation, the condition variable is "false" until it becomes
380	"true" by calling the "send" method (or calling the condition variable	535	"true" by calling the "send" method (or calling the condition variable
381	as if it were a callback, read about the caveats in the description for	536	as if it were a callback, read about the caveats in the description for
382	the "->send" method).	537	the "->send" method).
…		…
384	Condition variables are similar to callbacks, except that you can	539	Condition variables are similar to callbacks, except that you can
385	optionally wait for them. They can also be called merge points - points	540	optionally wait for them. They can also be called merge points - points
386	in time where multiple outstanding events have been processed. And yet	541	in time where multiple outstanding events have been processed. And yet
387	another way to call them is transactions - each condition variable can	542	another way to call them is transactions - each condition variable can
388	be used to represent a transaction, which finishes at some point and	543	be used to represent a transaction, which finishes at some point and
389	delivers a result.	544	delivers a result. And yet some people know them as "futures" - a
		545	promise to compute/deliver something that you can wait for.
390		546
391	Condition variables are very useful to signal that something has	547	Condition variables are very useful to signal that something has
392	finished, for example, if you write a module that does asynchronous http	548	finished, for example, if you write a module that does asynchronous http
393	requests, then a condition variable would be the ideal candidate to	549	requests, then a condition variable would be the ideal candidate to
394	signal the availability of results. The user can either act when the	550	signal the availability of results. The user can either act when the
…		…
428	after => 1,	584	after => 1,
429	cb => sub { $result_ready->send },	585	cb => sub { $result_ready->send },
430	);	586	);
431		587
432	# this "blocks" (while handling events) till the callback	588	# this "blocks" (while handling events) till the callback
433	# calls send	589	# calls ->send
434	$result_ready->recv;	590	$result_ready->recv;
435		591
436	Example: wait for a timer, but take advantage of the fact that condition	592	Example: wait for a timer, but take advantage of the fact that condition
437	variables are also code references.	593	variables are also callable directly.
438		594
439	my $done = AnyEvent->condvar;	595	my $done = AnyEvent->condvar;
440	my $delay = AnyEvent->timer (after => 5, cb => $done);	596	my $delay = AnyEvent->timer (after => 5, cb => $done);
441	$done->recv;	597	$done->recv;
		598
		599	Example: Imagine an API that returns a condvar and doesn't support
		600	callbacks. This is how you make a synchronous call, for example from the
		601	main program:
		602
		603	use AnyEvent::CouchDB;
		604
		605	...
		606
		607	my @info = $couchdb->info->recv;
		608
		609	And this is how you would just set a callback to be called whenever the
		610	results are available:
		611
		612	$couchdb->info->cb (sub {
		613	my @info = $_[0]->recv;
		614	});
442		615
443	METHODS FOR PRODUCERS	616	METHODS FOR PRODUCERS
444	These methods should only be used by the producing side, i.e. the	617	These methods should only be used by the producing side, i.e. the
445	code/module that eventually sends the signal. Note that it is also the	618	code/module that eventually sends the signal. Note that it is also the
446	producer side which creates the condvar in most cases, but it isn't	619	producer side which creates the condvar in most cases, but it isn't
…		…
456		629
457	Any arguments passed to the "send" call will be returned by all	630	Any arguments passed to the "send" call will be returned by all
458	future "->recv" calls.	631	future "->recv" calls.
459		632
460	Condition variables are overloaded so one can call them directly (as	633	Condition variables are overloaded so one can call them directly (as
461	a code reference). Calling them directly is the same as calling	634	if they were a code reference). Calling them directly is the same as
462	"send". Note, however, that many C-based event loops do not handle	635	calling "send".
463	overloading, so as tempting as it may be, passing a condition
464	variable instead of a callback does not work. Both the pure perl and
465	EV loops support overloading, however, as well as all functions that
466	use perl to invoke a callback (as in AnyEvent::Socket and
467	AnyEvent::DNS for example).
468		636
469	$cv->croak ($error)	637	$cv->croak ($error)
470	Similar to send, but causes all call's to "->recv" to invoke	638	Similar to send, but causes all call's to "->recv" to invoke
471	"Carp::croak" with the given error message/object/scalar.	639	"Carp::croak" with the given error message/object/scalar.
472		640
473	This can be used to signal any errors to the condition variable	641	This can be used to signal any errors to the condition variable
474	user/consumer.	642	user/consumer. Doing it this way instead of calling "croak" directly
		643	delays the error detetcion, but has the overwhelmign advantage that
		644	it diagnoses the error at the place where the result is expected,
		645	and not deep in some event clalback without connection to the actual
		646	code causing the problem.
475		647
476	$cv->begin ([group callback])	648	$cv->begin ([group callback])
477	$cv->end	649	$cv->end
478	These two methods are EXPERIMENTAL and MIGHT CHANGE.
479
480	These two methods can be used to combine many transactions/events	650	These two methods can be used to combine many transactions/events
481	into one. For example, a function that pings many hosts in parallel	651	into one. For example, a function that pings many hosts in parallel
482	might want to use a condition variable for the whole process.	652	might want to use a condition variable for the whole process.
483		653
484	Every call to "->begin" will increment a counter, and every call to	654	Every call to "->begin" will increment a counter, and every call to
485	"->end" will decrement it. If the counter reaches 0 in "->end", the	655	"->end" will decrement it. If the counter reaches 0 in "->end", the
486	(last) callback passed to "begin" will be executed. That callback is	656	(last) callback passed to "begin" will be executed, passing the
487	supposed to call "->send", but that is not required. If no	657	condvar as first argument. That callback is supposed to call
		658	"->send", but that is not required. If no group callback was set,
488	callback was set, "send" will be called without any arguments.	659	"send" will be called without any arguments.
489		660
490	Let's clarify this with the ping example:	661	You can think of "$cv->send" giving you an OR condition (one call
		662	sends), while "$cv->begin" and "$cv->end" giving you an AND
		663	condition (all "begin" calls must be "end"'ed before the condvar
		664	sends).
		665
		666	Let's start with a simple example: you have two I/O watchers (for
		667	example, STDOUT and STDERR for a program), and you want to wait for
		668	both streams to close before activating a condvar:
491		669
492	my $cv = AnyEvent->condvar;	670	my $cv = AnyEvent->condvar;
493		671
		672	$cv->begin; # first watcher
		673	my $w1 = AnyEvent->io (fh => $fh1, cb => sub {
		674	defined sysread $fh1, my $buf, 4096
		675	or $cv->end;
		676	});
		677
		678	$cv->begin; # second watcher
		679	my $w2 = AnyEvent->io (fh => $fh2, cb => sub {
		680	defined sysread $fh2, my $buf, 4096
		681	or $cv->end;
		682	});
		683
		684	$cv->recv;
		685
		686	This works because for every event source (EOF on file handle),
		687	there is one call to "begin", so the condvar waits for all calls to
		688	"end" before sending.
		689
		690	The ping example mentioned above is slightly more complicated, as
		691	the there are results to be passwd back, and the number of tasks
		692	that are begung can potentially be zero:
		693
		694	my $cv = AnyEvent->condvar;
		695
494	my %result;	696	my %result;
495	$cv->begin (sub { $cv->send (\%result) });	697	$cv->begin (sub { shift->send (\%result) });
496		698
497	for my $host (@list_of_hosts) {	699	for my $host (@list_of_hosts) {
498	$cv->begin;	700	$cv->begin;
499	ping_host_then_call_callback $host, sub {	701	ping_host_then_call_callback $host, sub {
500	$result{$host} = ...;	702	$result{$host} = ...;
…		…
515	the loop, which serves two important purposes: first, it sets the	717	the loop, which serves two important purposes: first, it sets the
516	callback to be called once the counter reaches 0, and second, it	718	callback to be called once the counter reaches 0, and second, it
517	ensures that "send" is called even when "no" hosts are being pinged	719	ensures that "send" is called even when "no" hosts are being pinged
518	(the loop doesn't execute once).	720	(the loop doesn't execute once).
519		721
520	This is the general pattern when you "fan out" into multiple	722	This is the general pattern when you "fan out" into multiple (but
521	subrequests: use an outer "begin"/"end" pair to set the callback and	723	potentially none) subrequests: use an outer "begin"/"end" pair to
522	ensure "end" is called at least once, and then, for each subrequest	724	set the callback and ensure "end" is called at least once, and then,
523	you start, call "begin" and for each subrequest you finish, call	725	for each subrequest you start, call "begin" and for each subrequest
524	"end".	726	you finish, call "end".
525		727
526	METHODS FOR CONSUMERS	728	METHODS FOR CONSUMERS
527	These methods should only be used by the consuming side, i.e. the code	729	These methods should only be used by the consuming side, i.e. the code
528	awaits the condition.	730	awaits the condition.
529		731
…		…
538	function will call "croak".	740	function will call "croak".
539		741
540	In list context, all parameters passed to "send" will be returned,	742	In list context, all parameters passed to "send" will be returned,
541	in scalar context only the first one will be returned.	743	in scalar context only the first one will be returned.
542		744
		745	Note that doing a blocking wait in a callback is not supported by
		746	any event loop, that is, recursive invocation of a blocking "->recv"
		747	is not allowed, and the "recv" call will "croak" if such a condition
		748	is detected. This condition can be slightly loosened by using
		749	Coro::AnyEvent, which allows you to do a blocking "->recv" from any
		750	thread that doesn't run the event loop itself.
		751
543	Not all event models support a blocking wait - some die in that case	752	Not all event models support a blocking wait - some die in that case
544	(programs might want to do that to stay interactive), so *if you are	753	(programs might want to do that to stay interactive), so *if you are
545	using this from a module, never require a blocking wait*, but let	754	using this from a module, never require a blocking wait*. Instead,
546	the caller decide whether the call will block or not (for example,	755	let the caller decide whether the call will block or not (for
547	by coupling condition variables with some kind of request results	756	example, by coupling condition variables with some kind of request
548	and supporting callbacks so the caller knows that getting the result	757	results and supporting callbacks so the caller knows that getting
549	will not block, while still supporting blocking waits if the caller	758	the result will not block, while still supporting blocking waits if
550	so desires).	759	the caller so desires).
551
552	Another reason never to "->recv" in a module is that you cannot
553	sensibly have two "->recv"'s in parallel, as that would require
554	multiple interpreters or coroutines/threads, none of which
555	"AnyEvent" can supply.
556
557	The Coro module, however, can and does supply coroutines and, in
558	fact, Coro::AnyEvent replaces AnyEvent's condvars by coroutine-safe
559	versions and also integrates coroutines into AnyEvent, making
560	blocking "->recv" calls perfectly safe as long as they are done from
561	another coroutine (one that doesn't run the event loop).
562		760
563	You can ensure that "-recv" never blocks by setting a callback and	761	You can ensure that "-recv" never blocks by setting a callback and
564	only calling "->recv" from within that callback (or at a later	762	only calling "->recv" from within that callback (or at a later
565	time). This will work even when the event loop does not support	763	time). This will work even when the event loop does not support
566	blocking waits otherwise.	764	blocking waits otherwise.
567		765
568	$bool = $cv->ready	766	$bool = $cv->ready
569	Returns true when the condition is "true", i.e. whether "send" or	767	Returns true when the condition is "true", i.e. whether "send" or
570	"croak" have been called.	768	"croak" have been called.
571		769
572	$cb = $cv->cb ([new callback])	770	$cb = $cv->cb ($cb->($cv))
573	This is a mutator function that returns the callback set and	771	This is a mutator function that returns the callback set and
574	optionally replaces it before doing so.	772	optionally replaces it before doing so.
575		773
576	The callback will be called when the condition becomes "true", i.e.	774	The callback will be called when the condition becomes (or already
577	when "send" or "croak" are called, with the only argument being the	775	was) "true", i.e. when "send" or "croak" are called (or were
578	condition variable itself. Calling "recv" inside the callback or at	776	called), with the only argument being the condition variable itself.
		777	Calling "recv" inside the callback or at any later time is
579	any later time is guaranteed not to block.	778	guaranteed not to block.
		779
		780	SUPPORTED EVENT LOOPS/BACKENDS
		781	The available backend classes are (every class has its own manpage):
		782
		783	Backends that are autoprobed when no other event loop can be found.
		784	EV is the preferred backend when no other event loop seems to be in
		785	use. If EV is not installed, then AnyEvent will fall back to its own
		786	pure-perl implementation, which is available everywhere as it comes
		787	with AnyEvent itself.
		788
		789	AnyEvent::Impl::EV based on EV (interface to libev, best choice).
		790	AnyEvent::Impl::Perl pure-perl implementation, fast and portable.
		791
		792	Backends that are transparently being picked up when they are used.
		793	These will be used when they are currently loaded when the first
		794	watcher is created, in which case it is assumed that the application
		795	is using them. This means that AnyEvent will automatically pick the
		796	right backend when the main program loads an event module before
		797	anything starts to create watchers. Nothing special needs to be done
		798	by the main program.
		799
		800	AnyEvent::Impl::Event based on Event, very stable, few glitches.
		801	AnyEvent::Impl::Glib based on Glib, slow but very stable.
		802	AnyEvent::Impl::Tk based on Tk, very broken.
		803	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
		804	AnyEvent::Impl::POE based on POE, very slow, some limitations.
		805	AnyEvent::Impl::Irssi used when running within irssi.
		806
		807	Backends with special needs.
		808	Qt requires the Qt::Application to be instantiated first, but will
		809	otherwise be picked up automatically. As long as the main program
		810	instantiates the application before any AnyEvent watchers are
		811	created, everything should just work.
		812
		813	AnyEvent::Impl::Qt based on Qt.
		814
		815	Support for IO::Async can only be partial, as it is too broken and
		816	architecturally limited to even support the AnyEvent API. It also is
		817	the only event loop that needs the loop to be set explicitly, so it
		818	can only be used by a main program knowing about AnyEvent. See
		819	AnyEvent::Impl::Async for the gory details.
		820
		821	AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed.
		822
		823	Event loops that are indirectly supported via other backends.
		824	Some event loops can be supported via other modules:
		825
		826	There is no direct support for WxWidgets (Wx) or Prima.
		827
		828	WxWidgets has no support for watching file handles. However, you can
		829	use WxWidgets through the POE adaptor, as POE has a Wx backend that
		830	simply polls 20 times per second, which was considered to be too
		831	horrible to even consider for AnyEvent.
		832
		833	Prima is not supported as nobody seems to be using it, but it has a
		834	POE backend, so it can be supported through POE.
		835
		836	AnyEvent knows about both Prima and Wx, however, and will try to
		837	load POE when detecting them, in the hope that POE will pick them
		838	up, in which case everything will be automatic.
580		839
581	GLOBAL VARIABLES AND FUNCTIONS	840	GLOBAL VARIABLES AND FUNCTIONS
		841	These are not normally required to use AnyEvent, but can be useful to
		842	write AnyEvent extension modules.
		843
582	$AnyEvent::MODEL	844	$AnyEvent::MODEL
583	Contains "undef" until the first watcher is being created. Then it	845	Contains "undef" until the first watcher is being created, before
		846	the backend has been autodetected.
		847
584	contains the event model that is being used, which is the name of	848	Afterwards it contains the event model that is being used, which is
585	the Perl class implementing the model. This class is usually one of	849	the name of the Perl class implementing the model. This class is
586	the "AnyEvent::Impl:xxx" modules, but can be any other class in the	850	usually one of the "AnyEvent::Impl:xxx" modules, but can be any
587	case AnyEvent has been extended at runtime (e.g. in rxvt-unicode).	851	other class in the case AnyEvent has been extended at runtime (e.g.
588		852	in rxvt-unicode it will be "urxvt::anyevent").
589	The known classes so far are:
590
591	AnyEvent::Impl::EV based on EV (an interface to libev, best choice).
592	AnyEvent::Impl::Event based on Event, second best choice.
593	AnyEvent::Impl::Perl pure-perl implementation, fast and portable.
594	AnyEvent::Impl::Glib based on Glib, third-best choice.
595	AnyEvent::Impl::Tk based on Tk, very bad choice.
596	AnyEvent::Impl::Qt based on Qt, cannot be autoprobed (see its docs).
597	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
598	AnyEvent::Impl::POE based on POE, not generic enough for full support.
599
600	There is no support for WxWidgets, as WxWidgets has no support for
601	watching file handles. However, you can use WxWidgets through the
602	POE Adaptor, as POE has a Wx backend that simply polls 20 times per
603	second, which was considered to be too horrible to even consider for
604	AnyEvent. Likewise, other POE backends can be used by AnyEvent by
605	using it's adaptor.
606
607	AnyEvent knows about Prima and Wx and will try to use POE when
608	autodetecting them.
609		853
610	AnyEvent::detect	854	AnyEvent::detect
611	Returns $AnyEvent::MODEL, forcing autodetection of the event model	855	Returns $AnyEvent::MODEL, forcing autodetection of the event model
612	if necessary. You should only call this function right before you	856	if necessary. You should only call this function right before you
613	would have created an AnyEvent watcher anyway, that is, as late as	857	would have created an AnyEvent watcher anyway, that is, as late as
614	possible at runtime.	858	possible at runtime, and not e.g. while initialising of your module.
		859
		860	If you need to do some initialisation before AnyEvent watchers are
		861	created, use "post_detect".
615		862
616	$guard = AnyEvent::post_detect { BLOCK }	863	$guard = AnyEvent::post_detect { BLOCK }
617	Arranges for the code block to be executed as soon as the event	864	Arranges for the code block to be executed as soon as the event
618	model is autodetected (or immediately if this has already happened).	865	model is autodetected (or immediately if this has already happened).
619		866
		867	The block will be executed after the actual backend has been
		868	detected ($AnyEvent::MODEL is set), but before any watchers have
		869	been created, so it is possible to e.g. patch @AnyEvent::ISA or do
		870	other initialisations - see the sources of AnyEvent::Strict or
		871	AnyEvent::AIO to see how this is used.
		872
		873	The most common usage is to create some global watchers, without
		874	forcing event module detection too early, for example, AnyEvent::AIO
		875	creates and installs the global IO::AIO watcher in a "post_detect"
		876	block to avoid autodetecting the event module at load time.
		877
620	If called in scalar or list context, then it creates and returns an	878	If called in scalar or list context, then it creates and returns an
621	object that automatically removes the callback again when it is	879	object that automatically removes the callback again when it is
		880	destroyed (or "undef" when the hook was immediately executed). See
622	destroyed. See Coro::BDB for a case where this is useful.	881	AnyEvent::AIO for a case where this is useful.
		882
		883	Example: Create a watcher for the IO::AIO module and store it in
		884	$WATCHER. Only do so after the event loop is initialised, though.
		885
		886	our WATCHER;
		887
		888	my $guard = AnyEvent::post_detect {
		889	$WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb);
		890	};
		891
		892	# the \|\|= is important in case post_detect immediately runs the block,
		893	# as to not clobber the newly-created watcher. assigning both watcher and
		894	# post_detect guard to the same variable has the advantage of users being
		895	# able to just C<undef $WATCHER> if the watcher causes them grief.
		896
		897	$WATCHER \|\|= $guard;
623		898
624	@AnyEvent::post_detect	899	@AnyEvent::post_detect
625	If there are any code references in this array (you can "push" to it	900	If there are any code references in this array (you can "push" to it
626	before or after loading AnyEvent), then they will called directly	901	before or after loading AnyEvent), then they will called directly
627	after the event loop has been chosen.	902	after the event loop has been chosen.
628		903
629	You should check $AnyEvent::MODEL before adding to this array,	904	You should check $AnyEvent::MODEL before adding to this array,
630	though: if it contains a true value then the event loop has already	905	though: if it is defined then the event loop has already been
631	been detected, and the array will be ignored.	906	detected, and the array will be ignored.
632		907
633	Best use "AnyEvent::post_detect { BLOCK }" instead.	908	Best use "AnyEvent::post_detect { BLOCK }" when your application
		909	allows it,as it takes care of these details.
		910
		911	This variable is mainly useful for modules that can do something
		912	useful when AnyEvent is used and thus want to know when it is
		913	initialised, but do not need to even load it by default. This array
		914	provides the means to hook into AnyEvent passively, without loading
		915	it.
634		916
635	WHAT TO DO IN A MODULE	917	WHAT TO DO IN A MODULE
636	As a module author, you should "use AnyEvent" and call AnyEvent methods	918	As a module author, you should "use AnyEvent" and call AnyEvent methods
637	freely, but you should not load a specific event module or rely on it.	919	freely, but you should not load a specific event module or rely on it.
638		920
…		…
689	variable somewhere, waiting for it, and sending it when the program	971	variable somewhere, waiting for it, and sending it when the program
690	should exit cleanly.	972	should exit cleanly.
691		973
692	OTHER MODULES	974	OTHER MODULES
693	The following is a non-exhaustive list of additional modules that use	975	The following is a non-exhaustive list of additional modules that use
694	AnyEvent and can therefore be mixed easily with other AnyEvent modules	976	AnyEvent as a client and can therefore be mixed easily with other
695	in the same program. Some of the modules come with AnyEvent, some are	977	AnyEvent modules and other event loops in the same program. Some of the
696	available via CPAN.	978	modules come with AnyEvent, most are available via CPAN.
697		979
698	AnyEvent::Util	980	AnyEvent::Util
699	Contains various utility functions that replace often-used but	981	Contains various utility functions that replace often-used but
700	blocking functions such as "inet_aton" by event-/callback-based	982	blocking functions such as "inet_aton" by event-/callback-based
701	versions.	983	versions.
…		…
707	more.	989	more.
708		990
709	AnyEvent::Handle	991	AnyEvent::Handle
710	Provide read and write buffers, manages watchers for reads and	992	Provide read and write buffers, manages watchers for reads and
711	writes, supports raw and formatted I/O, I/O queued and fully	993	writes, supports raw and formatted I/O, I/O queued and fully
712	transparent and non-blocking SSL/TLS.	994	transparent and non-blocking SSL/TLS (via AnyEvent::TLS.
713		995
714	AnyEvent::DNS	996	AnyEvent::DNS
715	Provides rich asynchronous DNS resolver capabilities.	997	Provides rich asynchronous DNS resolver capabilities.
716		998
717	AnyEvent::HTTP	999	AnyEvent::HTTP
…		…
738		1020
739	AnyEvent::GPSD	1021	AnyEvent::GPSD
740	A non-blocking interface to gpsd, a daemon delivering GPS	1022	A non-blocking interface to gpsd, a daemon delivering GPS
741	information.	1023	information.
742		1024
		1025	AnyEvent::IRC
		1026	AnyEvent based IRC client module family (replacing the older
		1027	Net::IRC3).
		1028
		1029	AnyEvent::XMPP
		1030	AnyEvent based XMPP (Jabber protocol) module family (replacing the
		1031	older Net::XMPP2>.
		1032
743	AnyEvent::IGS	1033	AnyEvent::IGS
744	A non-blocking interface to the Internet Go Server protocol (used by	1034	A non-blocking interface to the Internet Go Server protocol (used by
745	App::IGS).	1035	App::IGS).
746		1036
747	Net::IRC3
748	AnyEvent based IRC client module family.
749
750	Net::XMPP2
751	AnyEvent based XMPP (Jabber protocol) module family.
752
753	Net::FCP	1037	Net::FCP
754	AnyEvent-based implementation of the Freenet Client Protocol,	1038	AnyEvent-based implementation of the Freenet Client Protocol,
755	birthplace of AnyEvent.	1039	birthplace of AnyEvent.
756		1040
757	Event::ExecFlow	1041	Event::ExecFlow
758	High level API for event-based execution flow control.	1042	High level API for event-based execution flow control.
759		1043
760	Coro	1044	Coro
761	Has special support for AnyEvent via Coro::AnyEvent.	1045	Has special support for AnyEvent via Coro::AnyEvent.
762		1046
763	IO::Lambda	1047	SIMPLIFIED AE API
764	The lambda approach to I/O - don't ask, look there. Can use	1048	Starting with version 5.0, AnyEvent officially supports a second, much
765	AnyEvent.	1049	simpler, API that is designed to reduce the calling, typing and memory
		1050	overhead.
766		1051
767	SUPPLYING YOUR OWN EVENT MODEL INTERFACE	1052	See the AE manpage for details.
768	This is an advanced topic that you do not normally need to use AnyEvent
769	in a module. This section is only of use to event loop authors who want
770	to provide AnyEvent compatibility.
771		1053
772	If you need to support another event library which isn't directly	1054	ERROR AND EXCEPTION HANDLING
773	supported by AnyEvent, you can supply your own interface to it by	1055	In general, AnyEvent does not do any error handling - it relies on the
774	pushing, before the first watcher gets created, the package name of the	1056	caller to do that if required. The AnyEvent::Strict module (see also the
775	event module and the package name of the interface to use onto	1057	"PERL_ANYEVENT_STRICT" environment variable, below) provides strict
776	@AnyEvent::REGISTRY. You can do that before and even without loading	1058	checking of all AnyEvent methods, however, which is highly useful during
777	AnyEvent, so it is reasonably cheap.	1059	development.
778		1060
779	Example:	1061	As for exception handling (i.e. runtime errors and exceptions thrown
		1062	while executing a callback), this is not only highly event-loop
		1063	specific, but also not in any way wrapped by this module, as this is the
		1064	job of the main program.
780		1065
781	push @AnyEvent::REGISTRY, [urxvt => urxvt::anyevent::];	1066	The pure perl event loop simply re-throws the exception (usually within
782		1067	"condvar->recv"), the Event and EV modules call "$Event/EV::DIED->()",
783	This tells AnyEvent to (literally) use the "urxvt::anyevent::"	1068	Glib uses "install_exception_handler" and so on.
784	package/class when it finds the "urxvt" package/module is already
785	loaded.
786
787	When AnyEvent is loaded and asked to find a suitable event model, it
788	will first check for the presence of urxvt by trying to "use" the
789	"urxvt::anyevent" module.
790
791	The class should provide implementations for all watcher types. See
792	AnyEvent::Impl::EV (source code), AnyEvent::Impl::Glib (Source code) and
793	so on for actual examples. Use "perldoc -m AnyEvent::Impl::Glib" to see
794	the sources.
795
796	If you don't provide "signal" and "child" watchers than AnyEvent will
797	provide suitable (hopefully) replacements.
798
799	The above example isn't fictitious, the rxvt-unicode (a.k.a. urxvt)
800	terminal emulator uses the above line as-is. An interface isn't included
801	in AnyEvent because it doesn't make sense outside the embedded
802	interpreter inside rxvt-unicode, and it is updated and maintained as
803	part of the rxvt-unicode distribution.
804
805	rxvt-unicode also cheats a bit by not providing blocking access to
806	condition variables: code blocking while waiting for a condition will
807	"die". This still works with most modules/usages, and blocking calls
808	must not be done in an interactive application, so it makes sense.
809		1069
810	ENVIRONMENT VARIABLES	1070	ENVIRONMENT VARIABLES
811	The following environment variables are used by this module:	1071	The following environment variables are used by this module or its
		1072	submodules.
		1073
		1074	Note that AnyEvent will remove all environment variables starting with
		1075	"PERL_ANYEVENT_" from %ENV when it is loaded while taint mode is
		1076	enabled.
812		1077
813	"PERL_ANYEVENT_VERBOSE"	1078	"PERL_ANYEVENT_VERBOSE"
814	By default, AnyEvent will be completely silent except in fatal	1079	By default, AnyEvent will be completely silent except in fatal
815	conditions. You can set this environment variable to make AnyEvent	1080	conditions. You can set this environment variable to make AnyEvent
816	more talkative.	1081	more talkative.
…		…
819	conditions, such as not being able to load the event model specified	1084	conditions, such as not being able to load the event model specified
820	by "PERL_ANYEVENT_MODEL".	1085	by "PERL_ANYEVENT_MODEL".
821		1086
822	When set to 2 or higher, cause AnyEvent to report to STDERR which	1087	When set to 2 or higher, cause AnyEvent to report to STDERR which
823	event model it chooses.	1088	event model it chooses.
		1089
		1090	When set to 8 or higher, then AnyEvent will report extra information
		1091	on which optional modules it loads and how it implements certain
		1092	features.
824		1093
825	"PERL_ANYEVENT_STRICT"	1094	"PERL_ANYEVENT_STRICT"
826	AnyEvent does not do much argument checking by default, as thorough	1095	AnyEvent does not do much argument checking by default, as thorough
827	argument checking is very costly. Setting this variable to a true	1096	argument checking is very costly. Setting this variable to a true
828	value will cause AnyEvent to load "AnyEvent::Strict" and then to	1097	value will cause AnyEvent to load "AnyEvent::Strict" and then to
829	thoroughly check the arguments passed to most method calls. If it	1098	thoroughly check the arguments passed to most method calls. If it
830	finds any problems it will croak.	1099	finds any problems, it will croak.
831		1100
832	In other words, enables "strict" mode.	1101	In other words, enables "strict" mode.
833		1102
834	Unlike "use strict" it is definitely recommended ot keep it off in	1103	Unlike "use strict" (or it's modern cousin, "use common::sense", it
835	production.	1104	is definitely recommended to keep it off in production. Keeping
		1105	"PERL_ANYEVENT_STRICT=1" in your environment while developing
		1106	programs can be very useful, however.
836		1107
837	"PERL_ANYEVENT_MODEL"	1108	"PERL_ANYEVENT_MODEL"
838	This can be used to specify the event model to be used by AnyEvent,	1109	This can be used to specify the event model to be used by AnyEvent,
839	before auto detection and -probing kicks in. It must be a string	1110	before auto detection and -probing kicks in. It must be a string
840	consisting entirely of ASCII letters. The string "AnyEvent::Impl::"	1111	consisting entirely of ASCII letters. The string "AnyEvent::Impl::"
…		…
859	mentioned will be used, and preference will be given to protocols	1130	mentioned will be used, and preference will be given to protocols
860	mentioned earlier in the list.	1131	mentioned earlier in the list.
861		1132
862	This variable can effectively be used for denial-of-service attacks	1133	This variable can effectively be used for denial-of-service attacks
863	against local programs (e.g. when setuid), although the impact is	1134	against local programs (e.g. when setuid), although the impact is
864	likely small, as the program has to handle connection errors	1135	likely small, as the program has to handle conenction and other
865	already-	1136	failures anyways.
866		1137
867	Examples: "PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6" - prefer IPv4 over	1138	Examples: "PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6" - prefer IPv4 over
868	IPv6, but support both and try to use both.	1139	IPv6, but support both and try to use both.
869	"PERL_ANYEVENT_PROTOCOLS=ipv4" - only support IPv4, never try to	1140	"PERL_ANYEVENT_PROTOCOLS=ipv4" - only support IPv4, never try to
870	resolve or contact IPv6 addresses.	1141	resolve or contact IPv6 addresses.
…		…
881	EDNS0 in its DNS requests.	1152	EDNS0 in its DNS requests.
882		1153
883	"PERL_ANYEVENT_MAX_FORKS"	1154	"PERL_ANYEVENT_MAX_FORKS"
884	The maximum number of child processes that	1155	The maximum number of child processes that
885	"AnyEvent::Util::fork_call" will create in parallel.	1156	"AnyEvent::Util::fork_call" will create in parallel.
		1157
		1158	"PERL_ANYEVENT_MAX_OUTSTANDING_DNS"
		1159	The default value for the "max_outstanding" parameter for the
		1160	default DNS resolver - this is the maximum number of parallel DNS
		1161	requests that are sent to the DNS server.
		1162
		1163	"PERL_ANYEVENT_RESOLV_CONF"
		1164	The file to use instead of /etc/resolv.conf (or OS-specific
		1165	configuration) in the default resolver. When set to the empty
		1166	string, no default config will be used.
		1167
		1168	"PERL_ANYEVENT_CA_FILE", "PERL_ANYEVENT_CA_PATH".
		1169	When neither "ca_file" nor "ca_path" was specified during
		1170	AnyEvent::TLS context creation, and either of these environment
		1171	variables exist, they will be used to specify CA certificate
		1172	locations instead of a system-dependent default.
		1173
		1174	"PERL_ANYEVENT_AVOID_GUARD" and "PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT"
		1175	When these are set to 1, then the respective modules are not loaded.
		1176	Mostly good for testing AnyEvent itself.
		1177
		1178	SUPPLYING YOUR OWN EVENT MODEL INTERFACE
		1179	This is an advanced topic that you do not normally need to use AnyEvent
		1180	in a module. This section is only of use to event loop authors who want
		1181	to provide AnyEvent compatibility.
		1182
		1183	If you need to support another event library which isn't directly
		1184	supported by AnyEvent, you can supply your own interface to it by
		1185	pushing, before the first watcher gets created, the package name of the
		1186	event module and the package name of the interface to use onto
		1187	@AnyEvent::REGISTRY. You can do that before and even without loading
		1188	AnyEvent, so it is reasonably cheap.
		1189
		1190	Example:
		1191
		1192	push @AnyEvent::REGISTRY, [urxvt => urxvt::anyevent::];
		1193
		1194	This tells AnyEvent to (literally) use the "urxvt::anyevent::"
		1195	package/class when it finds the "urxvt" package/module is already
		1196	loaded.
		1197
		1198	When AnyEvent is loaded and asked to find a suitable event model, it
		1199	will first check for the presence of urxvt by trying to "use" the
		1200	"urxvt::anyevent" module.
		1201
		1202	The class should provide implementations for all watcher types. See
		1203	AnyEvent::Impl::EV (source code), AnyEvent::Impl::Glib (Source code) and
		1204	so on for actual examples. Use "perldoc -m AnyEvent::Impl::Glib" to see
		1205	the sources.
		1206
		1207	If you don't provide "signal" and "child" watchers than AnyEvent will
		1208	provide suitable (hopefully) replacements.
		1209
		1210	The above example isn't fictitious, the rxvt-unicode (a.k.a. urxvt)
		1211	terminal emulator uses the above line as-is. An interface isn't included
		1212	in AnyEvent because it doesn't make sense outside the embedded
		1213	interpreter inside rxvt-unicode, and it is updated and maintained as
		1214	part of the rxvt-unicode distribution.
		1215
		1216	rxvt-unicode also cheats a bit by not providing blocking access to
		1217	condition variables: code blocking while waiting for a condition will
		1218	"die". This still works with most modules/usages, and blocking calls
		1219	must not be done in an interactive application, so it makes sense.
886		1220
887	EXAMPLE PROGRAM	1221	EXAMPLE PROGRAM
888	The following program uses an I/O watcher to read data from STDIN, a	1222	The following program uses an I/O watcher to read data from STDIN, a
889	timer to display a message once per second, and a condition variable to	1223	timer to display a message once per second, and a condition variable to
890	quit the program when the user enters quit:	1224	quit the program when the user enters quit:
…		…
902	warn "read: $input\n"; # output what has been read	1236	warn "read: $input\n"; # output what has been read
903	$cv->send if $input =~ /^q/i; # quit program if /^q/i	1237	$cv->send if $input =~ /^q/i; # quit program if /^q/i
904	},	1238	},
905	);	1239	);
906		1240
907	my $time_watcher; # can only be used once
908
909	sub new_timer {
910	$timer = AnyEvent->timer (after => 1, cb => sub {	1241	my $time_watcher = AnyEvent->timer (after => 1, interval => 1, cb => sub {
911	warn "timeout\n"; # print 'timeout' about every second	1242	warn "timeout\n"; # print 'timeout' at most every second
912	&new_timer; # and restart the time
913	});
914	}	1243	});
915
916	new_timer; # create first timer
917		1244
918	$cv->recv; # wait until user enters /^q/i	1245	$cv->recv; # wait until user enters /^q/i
919		1246
920	REAL-WORLD EXAMPLE	1247	REAL-WORLD EXAMPLE
921	Consider the Net::FCP module. It features (among others) the following	1248	Consider the Net::FCP module. It features (among others) the following
…		…
1048	through AnyEvent. The benchmark creates a lot of timers (with a zero	1375	through AnyEvent. The benchmark creates a lot of timers (with a zero
1049	timeout) and I/O watchers (watching STDOUT, a pty, to become writable,	1376	timeout) and I/O watchers (watching STDOUT, a pty, to become writable,
1050	which it is), lets them fire exactly once and destroys them again.	1377	which it is), lets them fire exactly once and destroys them again.
1051		1378
1052	Source code for this benchmark is found as eg/bench in the AnyEvent	1379	Source code for this benchmark is found as eg/bench in the AnyEvent
1053	distribution.	1380	distribution. It uses the AE interface, which makes a real difference
		1381	for the EV and Perl backends only.
1054		1382
1055	Explanation of the columns	1383	Explanation of the columns
1056	watcher is the number of event watchers created/destroyed. Since	1384	watcher is the number of event watchers created/destroyed. Since
1057	different event models feature vastly different performances, each event	1385	different event models feature vastly different performances, each event
1058	loop was given a number of watchers so that overall runtime is	1386	loop was given a number of watchers so that overall runtime is
…		…
1077	destroy is the time, in microseconds, that it takes to destroy a	1405	destroy is the time, in microseconds, that it takes to destroy a
1078	single watcher.	1406	single watcher.
1079		1407
1080	Results	1408	Results
1081	name watchers bytes create invoke destroy comment	1409	name watchers bytes create invoke destroy comment
1082	EV/EV 400000 244 0.56 0.46 0.31 EV native interface	1410	EV/EV 100000 223 0.47 0.43 0.27 EV native interface
1083	EV/Any 100000 244 2.50 0.46 0.29 EV + AnyEvent watchers	1411	EV/Any 100000 223 0.48 0.42 0.26 EV + AnyEvent watchers
1084	CoroEV/Any 100000 244 2.49 0.44 0.29 coroutines + Coro::Signal	1412	Coro::EV/Any 100000 223 0.47 0.42 0.26 coroutines + Coro::Signal
1085	Perl/Any 100000 513 4.92 0.87 1.12 pure perl implementation	1413	Perl/Any 100000 431 2.70 0.74 0.92 pure perl implementation
1086	Event/Event 16000 516 31.88 31.30 0.85 Event native interface	1414	Event/Event 16000 516 31.16 31.84 0.82 Event native interface
1087	Event/Any 16000 590 35.75 31.42 1.08 Event + AnyEvent watchers	1415	Event/Any 16000 1203 42.61 34.79 1.80 Event + AnyEvent watchers
		1416	IOAsync/Any 16000 1911 41.92 27.45 16.81 via IO::Async::Loop::IO_Poll
		1417	IOAsync/Any 16000 1726 40.69 26.37 15.25 via IO::Async::Loop::Epoll
1088	Glib/Any 16000 1357 98.22 12.41 54.00 quadratic behaviour	1418	Glib/Any 16000 1118 89.00 12.57 51.17 quadratic behaviour
1089	Tk/Any 2000 1860 26.97 67.98 14.00 SEGV with >> 2000 watchers	1419	Tk/Any 2000 1346 20.96 10.75 8.00 SEGV with >> 2000 watchers
1090	POE/Event 2000 6644 108.64 736.02 14.73 via POE::Loop::Event	1420	POE/Any 2000 6951 108.97 795.32 14.24 via POE::Loop::Event
1091	POE/Select 2000 6343 94.13 809.12 565.96 via POE::Loop::Select	1421	POE/Any 2000 6648 94.79 774.40 575.51 via POE::Loop::Select
1092		1422
1093	Discussion	1423	Discussion
1094	The benchmark does not measure scalability of the event loop very	1424	The benchmark does not measure scalability of the event loop very
1095	well. For example, a select-based event loop (such as the pure perl one)	1425	well. For example, a select-based event loop (such as the pure perl one)
1096	can never compete with an event loop that uses epoll when the number of	1426	can never compete with an event loop that uses epoll when the number of
…		…
1107	benchmark machine, handling an event takes roughly 1600 CPU cycles with	1437	benchmark machine, handling an event takes roughly 1600 CPU cycles with
1108	EV, 3100 CPU cycles with AnyEvent's pure perl loop and almost 3000000	1438	EV, 3100 CPU cycles with AnyEvent's pure perl loop and almost 3000000
1109	CPU cycles with POE.	1439	CPU cycles with POE.
1110		1440
1111	"EV" is the sole leader regarding speed and memory use, which are both	1441	"EV" is the sole leader regarding speed and memory use, which are both
1112	maximal/minimal, respectively. Even when going through AnyEvent, it uses	1442	maximal/minimal, respectively. When using the AE API there is zero
		1443	overhead (when going through the AnyEvent API create is about 5-6 times
		1444	slower, with other times being equal, so still uses far less memory than
1113	far less memory than any other event loop and is still faster than Event	1445	any other event loop and is still faster than Event natively).
1114	natively.
1115		1446
1116	The pure perl implementation is hit in a few sweet spots (both the	1447	The pure perl implementation is hit in a few sweet spots (both the
1117	constant timeout and the use of a single fd hit optimisations in the	1448	constant timeout and the use of a single fd hit optimisations in the
1118	perl interpreter and the backend itself). Nevertheless this shows that	1449	perl interpreter and the backend itself). Nevertheless this shows that
1119	it adds very little overhead in itself. Like any select-based backend	1450	it adds very little overhead in itself. Like any select-based backend
…		…
1121	few of them active), of course, but this was not subject of this	1452	few of them active), of course, but this was not subject of this
1122	benchmark.	1453	benchmark.
1123		1454
1124	The "Event" module has a relatively high setup and callback invocation	1455	The "Event" module has a relatively high setup and callback invocation
1125	cost, but overall scores in on the third place.	1456	cost, but overall scores in on the third place.
		1457
		1458	"IO::Async" performs admirably well, about on par with "Event", even
		1459	when using its pure perl backend.
1126		1460
1127	"Glib"'s memory usage is quite a bit higher, but it features a faster	1461	"Glib"'s memory usage is quite a bit higher, but it features a faster
1128	callback invocation and overall ends up in the same class as "Event".	1462	callback invocation and overall ends up in the same class as "Event".
1129	However, Glib scales extremely badly, doubling the number of watchers	1463	However, Glib scales extremely badly, doubling the number of watchers
1130	increases the processing time by more than a factor of four, making it	1464	increases the processing time by more than a factor of four, making it
…		…
1186	In this benchmark, we use 10000 socket pairs (20000 sockets), of which	1520	In this benchmark, we use 10000 socket pairs (20000 sockets), of which
1187	100 (1%) are active. This mirrors the activity of large servers with	1521	100 (1%) are active. This mirrors the activity of large servers with
1188	many connections, most of which are idle at any one point in time.	1522	many connections, most of which are idle at any one point in time.
1189		1523
1190	Source code for this benchmark is found as eg/bench2 in the AnyEvent	1524	Source code for this benchmark is found as eg/bench2 in the AnyEvent
1191	distribution.	1525	distribution. It uses the AE interface, which makes a real difference
		1526	for the EV and Perl backends only.
1192		1527
1193	Explanation of the columns	1528	Explanation of the columns
1194	sockets is the number of sockets, and twice the number of "servers"	1529	sockets is the number of sockets, and twice the number of "servers"
1195	(as each server has a read and write socket end).	1530	(as each server has a read and write socket end).
1196		1531
…		…
1201	single "request", that is, reading the token from the pipe and	1536	single "request", that is, reading the token from the pipe and
1202	forwarding it to another server. This includes deleting the old timeout	1537	forwarding it to another server. This includes deleting the old timeout
1203	and creating a new one that moves the timeout into the future.	1538	and creating a new one that moves the timeout into the future.
1204		1539
1205	Results	1540	Results
1206	name sockets create request	1541	name sockets create request
1207	EV 20000 69.01 11.16	1542	EV 20000 62.66 7.99
1208	Perl 20000 73.32 35.87	1543	Perl 20000 68.32 32.64
1209	Event 20000 212.62 257.32	1544	IOAsync 20000 174.06 101.15 epoll
1210	Glib 20000 651.16 1896.30	1545	IOAsync 20000 174.67 610.84 poll
		1546	Event 20000 202.69 242.91
		1547	Glib 20000 557.01 1689.52
1211	POE 20000 349.67 12317.24 uses POE::Loop::Event	1548	POE 20000 341.54 12086.32 uses POE::Loop::Event
1212		1549
1213	Discussion	1550	Discussion
1214	This benchmark does measure scalability and overall performance of the	1551	This benchmark does measure scalability and overall performance of the
1215	particular event loop.	1552	particular event loop.
1216		1553
1217	EV is again fastest. Since it is using epoll on my system, the setup	1554	EV is again fastest. Since it is using epoll on my system, the setup
1218	time is relatively high, though.	1555	time is relatively high, though.
1219		1556
1220	Perl surprisingly comes second. It is much faster than the C-based event	1557	Perl surprisingly comes second. It is much faster than the C-based event
1221	loops Event and Glib.	1558	loops Event and Glib.
		1559
		1560	IO::Async performs very well when using its epoll backend, and still
		1561	quite good compared to Glib when using its pure perl backend.
1222		1562
1223	Event suffers from high setup time as well (look at its code and you	1563	Event suffers from high setup time as well (look at its code and you
1224	will understand why). Callback invocation also has a high overhead	1564	will understand why). Callback invocation also has a high overhead
1225	compared to the "$_->() for .."-style loop that the Perl event loop	1565	compared to the "$_->() for .."-style loop that the Perl event loop
1226	uses. Event uses select or poll in basically all documented	1566	uses. Event uses select or poll in basically all documented
…		…
1277		1617
1278	Summary	1618	Summary
1279	* C-based event loops perform very well with small number of watchers,	1619	* C-based event loops perform very well with small number of watchers,
1280	as the management overhead dominates.	1620	as the management overhead dominates.
1281		1621
		1622	THE IO::Lambda BENCHMARK
		1623	Recently I was told about the benchmark in the IO::Lambda manpage, which
		1624	could be misinterpreted to make AnyEvent look bad. In fact, the
		1625	benchmark simply compares IO::Lambda with POE, and IO::Lambda looks
		1626	better (which shouldn't come as a surprise to anybody). As such, the
		1627	benchmark is fine, and mostly shows that the AnyEvent backend from
		1628	IO::Lambda isn't very optimal. But how would AnyEvent compare when used
		1629	without the extra baggage? To explore this, I wrote the equivalent
		1630	benchmark for AnyEvent.
		1631
		1632	The benchmark itself creates an echo-server, and then, for 500 times,
		1633	connects to the echo server, sends a line, waits for the reply, and then
		1634	creates the next connection. This is a rather bad benchmark, as it
		1635	doesn't test the efficiency of the framework or much non-blocking I/O,
		1636	but it is a benchmark nevertheless.
		1637
		1638	name runtime
		1639	Lambda/select 0.330 sec
		1640	+ optimized 0.122 sec
		1641	Lambda/AnyEvent 0.327 sec
		1642	+ optimized 0.138 sec
		1643	Raw sockets/select 0.077 sec
		1644	POE/select, components 0.662 sec
		1645	POE/select, raw sockets 0.226 sec
		1646	POE/select, optimized 0.404 sec
		1647
		1648	AnyEvent/select/nb 0.085 sec
		1649	AnyEvent/EV/nb 0.068 sec
		1650	+state machine 0.134 sec
		1651
		1652	The benchmark is also a bit unfair (my fault): the IO::Lambda/POE
		1653	benchmarks actually make blocking connects and use 100% blocking I/O,
		1654	defeating the purpose of an event-based solution. All of the newly
		1655	written AnyEvent benchmarks use 100% non-blocking connects (using
		1656	AnyEvent::Socket::tcp_connect and the asynchronous pure perl DNS
		1657	resolver), so AnyEvent is at a disadvantage here, as non-blocking
		1658	connects generally require a lot more bookkeeping and event handling
		1659	than blocking connects (which involve a single syscall only).
		1660
		1661	The last AnyEvent benchmark additionally uses AnyEvent::Handle, which
		1662	offers similar expressive power as POE and IO::Lambda, using
		1663	conventional Perl syntax. This means that both the echo server and the
		1664	client are 100% non-blocking, further placing it at a disadvantage.
		1665
		1666	As you can see, the AnyEvent + EV combination even beats the
		1667	hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl
		1668	backend easily beats IO::Lambda and POE.
		1669
		1670	And even the 100% non-blocking version written using the high-level (and
		1671	slow :) AnyEvent::Handle abstraction beats both POE and IO::Lambda
		1672	higher level ("unoptimised") abstractions by a large margin, even though
		1673	it does all of DNS, tcp-connect and socket I/O in a non-blocking way.
		1674
		1675	The two AnyEvent benchmarks programs can be found as eg/ae0.pl and
		1676	eg/ae2.pl in the AnyEvent distribution, the remaining benchmarks are
		1677	part of the IO::Lambda distribution and were used without any changes.
		1678
		1679	SIGNALS
		1680	AnyEvent currently installs handlers for these signals:
		1681
		1682	SIGCHLD
		1683	A handler for "SIGCHLD" is installed by AnyEvent's child watcher
		1684	emulation for event loops that do not support them natively. Also,
		1685	some event loops install a similar handler.
		1686
		1687	Additionally, when AnyEvent is loaded and SIGCHLD is set to IGNORE,
		1688	then AnyEvent will reset it to default, to avoid losing child exit
		1689	statuses.
		1690
		1691	SIGPIPE
		1692	A no-op handler is installed for "SIGPIPE" when $SIG{PIPE} is
		1693	"undef" when AnyEvent gets loaded.
		1694
		1695	The rationale for this is that AnyEvent users usually do not really
		1696	depend on SIGPIPE delivery (which is purely an optimisation for
		1697	shell use, or badly-written programs), but "SIGPIPE" can cause
		1698	spurious and rare program exits as a lot of people do not expect
		1699	"SIGPIPE" when writing to some random socket.
		1700
		1701	The rationale for installing a no-op handler as opposed to ignoring
		1702	it is that this way, the handler will be restored to defaults on
		1703	exec.
		1704
		1705	Feel free to install your own handler, or reset it to defaults.
		1706
		1707	RECOMMENDED/OPTIONAL MODULES
		1708	One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and
		1709	it's built-in modules) are required to use it.
		1710
		1711	That does not mean that AnyEvent won't take advantage of some additional
		1712	modules if they are installed.
		1713
		1714	This section epxlains which additional modules will be used, and how
		1715	they affect AnyEvent's operetion.
		1716
		1717	Async::Interrupt
		1718	This slightly arcane module is used to implement fast signal
		1719	handling: To my knowledge, there is no way to do completely
		1720	race-free and quick signal handling in pure perl. To ensure that
		1721	signals still get delivered, AnyEvent will start an interval timer
		1722	to wake up perl (and catch the signals) with some delay (default is
		1723	10 seconds, look for $AnyEvent::MAX_SIGNAL_LATENCY).
		1724
		1725	If this module is available, then it will be used to implement
		1726	signal catching, which means that signals will not be delayed, and
		1727	the event loop will not be interrupted regularly, which is more
		1728	efficient (And good for battery life on laptops).
		1729
		1730	This affects not just the pure-perl event loop, but also other event
		1731	loops that have no signal handling on their own (e.g. Glib, Tk, Qt).
		1732
		1733	Some event loops (POE, Event, Event::Lib) offer signal watchers
		1734	natively, and either employ their own workarounds (POE) or use
		1735	AnyEvent's workaround (using $AnyEvent::MAX_SIGNAL_LATENCY).
		1736	Installing Async::Interrupt does nothing for those backends.
		1737
		1738	EV This module isn't really "optional", as it is simply one of the
		1739	backend event loops that AnyEvent can use. However, it is simply the
		1740	best event loop available in terms of features, speed and stability:
		1741	It supports the AnyEvent API optimally, implements all the watcher
		1742	types in XS, does automatic timer adjustments even when no monotonic
		1743	clock is available, can take avdantage of advanced kernel interfaces
		1744	such as "epoll" and "kqueue", and is the fastest backend by far.
		1745	You can even embed Glib/Gtk2 in it (or vice versa, see EV::Glib and
		1746	Glib::EV).
		1747
		1748	Guard
		1749	The guard module, when used, will be used to implement
		1750	"AnyEvent::Util::guard". This speeds up guards considerably (and
		1751	uses a lot less memory), but otherwise doesn't affect guard
		1752	operation much. It is purely used for performance.
		1753
		1754	JSON and JSON::XS
		1755	One of these modules is required when you want to read or write JSON
		1756	data via AnyEvent::Handle. It is also written in pure-perl, but can
		1757	take advantage of the ultra-high-speed JSON::XS module when it is
		1758	installed.
		1759
		1760	In fact, AnyEvent::Handle will use JSON::XS by default if it is
		1761	installed.
		1762
		1763	Net::SSLeay
		1764	Implementing TLS/SSL in Perl is certainly interesting, but not very
		1765	worthwhile: If this module is installed, then AnyEvent::Handle (with
		1766	the help of AnyEvent::TLS), gains the ability to do TLS/SSL.
		1767
		1768	Time::HiRes
		1769	This module is part of perl since release 5.008. It will be used
		1770	when the chosen event library does not come with a timing source on
		1771	it's own. The pure-perl event loop (AnyEvent::Impl::Perl) will
		1772	additionally use it to try to use a monotonic clock for timing
		1773	stability.
		1774
1282	FORK	1775	FORK
1283	Most event libraries are not fork-safe. The ones who are usually are	1776	Most event libraries are not fork-safe. The ones who are usually are
1284	because they rely on inefficient but fork-safe "select" or "poll" calls.	1777	because they rely on inefficient but fork-safe "select" or "poll" calls.
1285	Only EV is fully fork-aware.	1778	Only EV is fully fork-aware.
1286		1779
1287	If you have to fork, you must either do so before creating your first	1780	If you have to fork, you must either do so before creating your first
1288	watcher OR you must not use AnyEvent at all in the child.	1781	watcher OR you must not use AnyEvent at all in the child OR you must do
		1782	something completely out of the scope of AnyEvent.
1289		1783
1290	SECURITY CONSIDERATIONS	1784	SECURITY CONSIDERATIONS
1291	AnyEvent can be forced to load any event model via	1785	AnyEvent can be forced to load any event model via
1292	$ENV{PERL_ANYEVENT_MODEL}. While this cannot (to my knowledge) be used	1786	$ENV{PERL_ANYEVENT_MODEL}. While this cannot (to my knowledge) be used
1293	to execute arbitrary code or directly gain access, it can easily be used	1787	to execute arbitrary code or directly gain access, it can easily be used
…		…
1297		1791
1298	You can make AnyEvent completely ignore this variable by deleting it	1792	You can make AnyEvent completely ignore this variable by deleting it
1299	before the first watcher gets created, e.g. with a "BEGIN" block:	1793	before the first watcher gets created, e.g. with a "BEGIN" block:
1300		1794
1301	BEGIN { delete $ENV{PERL_ANYEVENT_MODEL} }	1795	BEGIN { delete $ENV{PERL_ANYEVENT_MODEL} }
1302		1796
1303	use AnyEvent;	1797	use AnyEvent;
1304		1798
1305	Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can	1799	Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can
1306	be used to probe what backend is used and gain other information (which	1800	be used to probe what backend is used and gain other information (which
1307	is probably even less useful to an attacker than PERL_ANYEVENT_MODEL),	1801	is probably even less useful to an attacker than PERL_ANYEVENT_MODEL),
1308	and $ENV{PERL_ANYEGENT_STRICT}.	1802	and $ENV{PERL_ANYEVENT_STRICT}.
		1803
		1804	Note that AnyEvent will remove all environment variables starting with
		1805	"PERL_ANYEVENT_" from %ENV when it is loaded while taint mode is
		1806	enabled.
1309		1807
1310	BUGS	1808	BUGS
1311	Perl 5.8 has numerous memleaks that sometimes hit this module and are	1809	Perl 5.8 has numerous memleaks that sometimes hit this module and are
1312	hard to work around. If you suffer from memleaks, first upgrade to Perl	1810	hard to work around. If you suffer from memleaks, first upgrade to Perl
1313	5.10 and check wether the leaks still show up. (Perl 5.10.0 has other	1811	5.10 and check wether the leaks still show up. (Perl 5.10.0 has other
1314	annoying mamleaks, such as leaking on "map" and "grep" but it is usually	1812	annoying memleaks, such as leaking on "map" and "grep" but it is usually
1315	not as pronounced).	1813	not as pronounced).
1316		1814
1317	SEE ALSO	1815	SEE ALSO
1318	Utility functions: AnyEvent::Util.	1816	Utility functions: AnyEvent::Util.
1319		1817
1320	Event modules: EV, EV::Glib, Glib::EV, Event, Glib::Event, Glib, Tk,	1818	Event modules: EV, EV::Glib, Glib::EV, Event, Glib::Event, Glib, Tk,
1321	Event::Lib, Qt, POE.	1819	Event::Lib, Qt, POE.
1322		1820
1323	Implementations: AnyEvent::Impl::EV, AnyEvent::Impl::Event,	1821	Implementations: AnyEvent::Impl::EV, AnyEvent::Impl::Event,
1324	AnyEvent::Impl::Glib, AnyEvent::Impl::Tk, AnyEvent::Impl::Perl,	1822	AnyEvent::Impl::Glib, AnyEvent::Impl::Tk, AnyEvent::Impl::Perl,
1325	AnyEvent::Impl::EventLib, AnyEvent::Impl::Qt, AnyEvent::Impl::POE.	1823	AnyEvent::Impl::EventLib, AnyEvent::Impl::Qt, AnyEvent::Impl::POE,
		1824	AnyEvent::Impl::IOAsync, Anyevent::Impl::Irssi.
1326		1825
1327	Non-blocking file handles, sockets, TCP clients and servers:	1826	Non-blocking file handles, sockets, TCP clients and servers:
1328	AnyEvent::Handle, AnyEvent::Socket.	1827	AnyEvent::Handle, AnyEvent::Socket, AnyEvent::TLS.
1329		1828
1330	Asynchronous DNS: AnyEvent::DNS.	1829	Asynchronous DNS: AnyEvent::DNS.
1331		1830
1332	Coroutine support: Coro, Coro::AnyEvent, Coro::EV, Coro::Event,	1831	Coroutine support: Coro, Coro::AnyEvent, Coro::EV, Coro::Event,
1333		1832
1334	Nontrivial usage examples: Net::FCP, Net::XMPP2, AnyEvent::DNS.	1833	Nontrivial usage examples: AnyEvent::GPSD, AnyEvent::XMPP,
		1834	AnyEvent::HTTP.
1335		1835
1336	AUTHOR	1836	AUTHOR
1337	Marc Lehmann <schmorp@schmorp.de>	1837	Marc Lehmann <schmorp@schmorp.de>
1338	http://home.schmorp.de/	1838	http://home.schmorp.de/
1339		1839

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Comparing AnyEvent/README (file contents): Revision 1.28 by root, Sat Jul 12 20:45:27 2008 UTC vs. Revision 1.56 by root, Thu Nov 19 01:55:57 2009 UTC

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Comparing AnyEvent/README (file contents):
Revision 1.28 by root, Sat Jul 12 20:45:27 2008 UTC vs.
Revision 1.56 by root, Thu Nov 19 01:55:57 2009 UTC