ViewVC Help

View File | Revision Log | Show Annotations | Download File

/cvs/AnyEvent/lib/AnyEvent.pm

Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.283 by root, Wed Aug 12 15:50:44 2009 UTC vs.
Revision 1.345 by root, Fri Dec 31 04:50:44 2010 UTC

…		…
7		7
8	=head1 SYNOPSIS	8	=head1 SYNOPSIS
9		9
10	use AnyEvent;	10	use AnyEvent;
11		11
		12	# if you prefer function calls, look at the AE manpage for
		13	# an alternative API.
		14
12	# file descriptor readable	15	# file handle or descriptor readable
13	my $w = AnyEvent->io (fh => $fh, poll => "r", cb => sub { ... });	16	my $w = AnyEvent->io (fh => $fh, poll => "r", cb => sub { ... });
14		17
15	# one-shot or repeating timers	18	# one-shot or repeating timers
16	my $w = AnyEvent->timer (after => $seconds, cb => sub { ... });	19	my $w = AnyEvent->timer (after => $seconds, cb => sub { ... });
17	my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ...	20	my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ...);
18		21
19	print AnyEvent->now; # prints current event loop time	22	print AnyEvent->now; # prints current event loop time
20	print AnyEvent->time; # think Time::HiRes::time or simply CORE::time.	23	print AnyEvent->time; # think Time::HiRes::time or simply CORE::time.
21		24
22	# POSIX signal	25	# POSIX signal
…		…
43	in a tutorial or some gentle introduction, have a look at the	46	in a tutorial or some gentle introduction, have a look at the
44	L<AnyEvent::Intro> manpage.	47	L<AnyEvent::Intro> manpage.
45		48
46	=head1 SUPPORT	49	=head1 SUPPORT
47		50
		51	An FAQ document is available as L<AnyEvent::FAQ>.
		52
48	There is a mailinglist for discussing all things AnyEvent, and an IRC	53	There also is a mailinglist for discussing all things AnyEvent, and an IRC
49	channel, too.	54	channel, too.
50		55
51	See the AnyEvent project page at the B<Schmorpforge Ta-Sa Software	56	See the AnyEvent project page at the B<Schmorpforge Ta-Sa Software
52	Repository>, at L<http://anyevent.schmorp.de>, for more info.	57	Repository>, at L<http://anyevent.schmorp.de>, for more info.
53		58
…		…
73	module users into the same thing by forcing them to use the same event	78	module users into the same thing by forcing them to use the same event
74	model you use.	79	model you use.
75		80
76	For modules like POE or IO::Async (which is a total misnomer as it is	81	For modules like POE or IO::Async (which is a total misnomer as it is
77	actually doing all I/O I<synchronously>...), using them in your module is	82	actually doing all I/O I<synchronously>...), using them in your module is
78	like joining a cult: After you joined, you are dependent on them and you	83	like joining a cult: After you join, you are dependent on them and you
79	cannot use anything else, as they are simply incompatible to everything	84	cannot use anything else, as they are simply incompatible to everything
80	that isn't them. What's worse, all the potential users of your	85	that isn't them. What's worse, all the potential users of your
81	module are I<also> forced to use the same event loop you use.	86	module are I<also> forced to use the same event loop you use.
82		87
83	AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works	88	AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works
84	fine. AnyEvent + Tk works fine etc. etc. but none of these work together	89	fine. AnyEvent + Tk works fine etc. etc. but none of these work together
85	with the rest: POE + IO::Async? No go. Tk + Event? No go. Again: if	90	with the rest: POE + EV? No go. Tk + Event? No go. Again: if your module
86	your module uses one of those, every user of your module has to use it,	91	uses one of those, every user of your module has to use it, too. But if
87	too. But if your module uses AnyEvent, it works transparently with all	92	your module uses AnyEvent, it works transparently with all event models it
88	event models it supports (including stuff like IO::Async, as long as those	93	supports (including stuff like IO::Async, as long as those use one of the
89	use one of the supported event loops. It is trivial to add new event loops	94	supported event loops. It is easy to add new event loops to AnyEvent, too,
90	to AnyEvent, too, so it is future-proof).	95	so it is future-proof).
91		96
92	In addition to being free of having to use I<the one and only true event	97	In addition to being free of having to use I<the one and only true event
93	model>, AnyEvent also is free of bloat and policy: with POE or similar	98	model>, AnyEvent also is free of bloat and policy: with POE or similar
94	modules, you get an enormous amount of code and strict rules you have to	99	modules, you get an enormous amount of code and strict rules you have to
95	follow. AnyEvent, on the other hand, is lean and up to the point, by only	100	follow. AnyEvent, on the other hand, is lean and to the point, by only
96	offering the functionality that is necessary, in as thin as a wrapper as	101	offering the functionality that is necessary, in as thin as a wrapper as
97	technically possible.	102	technically possible.
98		103
99	Of course, AnyEvent comes with a big (and fully optional!) toolbox	104	Of course, AnyEvent comes with a big (and fully optional!) toolbox
100	of useful functionality, such as an asynchronous DNS resolver, 100%	105	of useful functionality, such as an asynchronous DNS resolver, 100%
…		…
106	useful) and you want to force your users to use the one and only event	111	useful) and you want to force your users to use the one and only event
107	model, you should I<not> use this module.	112	model, you should I<not> use this module.
108		113
109	=head1 DESCRIPTION	114	=head1 DESCRIPTION
110		115
111	L<AnyEvent> provides an identical interface to multiple event loops. This	116	L<AnyEvent> provides a uniform interface to various event loops. This
112	allows module authors to utilise an event loop without forcing module	117	allows module authors to use event loop functionality without forcing
113	users to use the same event loop (as only a single event loop can coexist	118	module users to use a specific event loop implementation (since more
114	peacefully at any one time).	119	than one event loop cannot coexist peacefully).
115		120
116	The interface itself is vaguely similar, but not identical to the L<Event>	121	The interface itself is vaguely similar, but not identical to the L<Event>
117	module.	122	module.
118		123
119	During the first call of any watcher-creation method, the module tries	124	During the first call of any watcher-creation method, the module tries
120	to detect the currently loaded event loop by probing whether one of the	125	to detect the currently loaded event loop by probing whether one of the
121	following modules is already loaded: L<EV>,	126	following modules is already loaded: L<EV>, L<AnyEvent::Impl::Perl>,
122	L<Event>, L<Glib>, L<AnyEvent::Impl::Perl>, L<Tk>, L<Event::Lib>, L<Qt>,	127	L<Event>, L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. The first one
123	L<POE>. The first one found is used. If none are found, the module tries	128	found is used. If none are detected, the module tries to load the first
124	to load these modules (excluding Tk, Event::Lib, Qt and POE as the pure perl	129	four modules in the order given; but note that if L<EV> is not
125	adaptor should always succeed) in the order given. The first one that can	130	available, the pure-perl L<AnyEvent::Impl::Perl> should always work, so
126	be successfully loaded will be used. If, after this, still none could be	131	the other two are not normally tried.
127	found, AnyEvent will fall back to a pure-perl event loop, which is not
128	very efficient, but should work everywhere.
129		132
130	Because AnyEvent first checks for modules that are already loaded, loading	133	Because AnyEvent first checks for modules that are already loaded, loading
131	an event model explicitly before first using AnyEvent will likely make	134	an event model explicitly before first using AnyEvent will likely make
132	that model the default. For example:	135	that model the default. For example:
133		136
…		…
135	use AnyEvent;	138	use AnyEvent;
136		139
137	# .. AnyEvent will likely default to Tk	140	# .. AnyEvent will likely default to Tk
138		141
139	The I<likely> means that, if any module loads another event model and	142	The I<likely> means that, if any module loads another event model and
140	starts using it, all bets are off. Maybe you should tell their authors to	143	starts using it, all bets are off - this case should be very rare though,
141	use AnyEvent so their modules work together with others seamlessly...	144	as very few modules hardcode event loops without announcing this very
		145	loudly.
142		146
143	The pure-perl implementation of AnyEvent is called	147	The pure-perl implementation of AnyEvent is called
144	C<AnyEvent::Impl::Perl>. Like other event modules you can load it	148	C<AnyEvent::Impl::Perl>. Like other event modules you can load it
145	explicitly and enjoy the high availability of that event loop :)	149	explicitly and enjoy the high availability of that event loop :)
146		150
…		…
155	callback when the event occurs (of course, only when the event model	159	callback when the event occurs (of course, only when the event model
156	is in control).	160	is in control).
157		161
158	Note that B<callbacks must not permanently change global variables>	162	Note that B<callbacks must not permanently change global variables>
159	potentially in use by the event loop (such as C<$_> or C<$[>) and that B<<	163	potentially in use by the event loop (such as C<$_> or C<$[>) and that B<<
160	callbacks must not C<die> >>. The former is good programming practise in	164	callbacks must not C<die> >>. The former is good programming practice in
161	Perl and the latter stems from the fact that exception handling differs	165	Perl and the latter stems from the fact that exception handling differs
162	widely between event loops.	166	widely between event loops.
163		167
164	To disable the watcher you have to destroy it (e.g. by setting the	168	To disable a watcher you have to destroy it (e.g. by setting the
165	variable you store it in to C<undef> or otherwise deleting all references	169	variable you store it in to C<undef> or otherwise deleting all references
166	to it).	170	to it).
167		171
168	All watchers are created by calling a method on the C<AnyEvent> class.	172	All watchers are created by calling a method on the C<AnyEvent> class.
169		173
170	Many watchers either are used with "recursion" (repeating timers for	174	Many watchers either are used with "recursion" (repeating timers for
171	example), or need to refer to their watcher object in other ways.	175	example), or need to refer to their watcher object in other ways.
172		176
173	An any way to achieve that is this pattern:	177	One way to achieve that is this pattern:
174		178
175	my $w; $w = AnyEvent->type (arg => value ..., cb => sub {	179	my $w; $w = AnyEvent->type (arg => value ..., cb => sub {
176	# you can use $w here, for example to undef it	180	# you can use $w here, for example to undef it
177	undef $w;	181	undef $w;
178	});	182	});
…		…
210		214
211	The I/O watcher might use the underlying file descriptor or a copy of it.	215	The I/O watcher might use the underlying file descriptor or a copy of it.
212	You must not close a file handle as long as any watcher is active on the	216	You must not close a file handle as long as any watcher is active on the
213	underlying file descriptor.	217	underlying file descriptor.
214		218
215	Some event loops issue spurious readyness notifications, so you should	219	Some event loops issue spurious readiness notifications, so you should
216	always use non-blocking calls when reading/writing from/to your file	220	always use non-blocking calls when reading/writing from/to your file
217	handles.	221	handles.
218		222
219	Example: wait for readability of STDIN, then read a line and disable the	223	Example: wait for readability of STDIN, then read a line and disable the
220	watcher.	224	watcher.
…		…
244		248
245	Although the callback might get passed parameters, their value and	249	Although the callback might get passed parameters, their value and
246	presence is undefined and you cannot rely on them. Portable AnyEvent	250	presence is undefined and you cannot rely on them. Portable AnyEvent
247	callbacks cannot use arguments passed to time watcher callbacks.	251	callbacks cannot use arguments passed to time watcher callbacks.
248		252
249	The callback will normally be invoked once only. If you specify another	253	The callback will normally be invoked only once. If you specify another
250	parameter, C<interval>, as a strictly positive number (> 0), then the	254	parameter, C<interval>, as a strictly positive number (> 0), then the
251	callback will be invoked regularly at that interval (in fractional	255	callback will be invoked regularly at that interval (in fractional
252	seconds) after the first invocation. If C<interval> is specified with a	256	seconds) after the first invocation. If C<interval> is specified with a
253	false value, then it is treated as if it were missing.	257	false value, then it is treated as if it were not specified at all.
254		258
255	The callback will be rescheduled before invoking the callback, but no	259	The callback will be rescheduled before invoking the callback, but no
256	attempt is done to avoid timer drift in most backends, so the interval is	260	attempt is made to avoid timer drift in most backends, so the interval is
257	only approximate.	261	only approximate.
258		262
259	Example: fire an event after 7.7 seconds.	263	Example: fire an event after 7.7 seconds.
260		264
261	my $w = AnyEvent->timer (after => 7.7, cb => sub {	265	my $w = AnyEvent->timer (after => 7.7, cb => sub {
…		…
279		283
280	While most event loops expect timers to specified in a relative way, they	284	While most event loops expect timers to specified in a relative way, they
281	use absolute time internally. This makes a difference when your clock	285	use absolute time internally. This makes a difference when your clock
282	"jumps", for example, when ntp decides to set your clock backwards from	286	"jumps", for example, when ntp decides to set your clock backwards from
283	the wrong date of 2014-01-01 to 2008-01-01, a watcher that is supposed to	287	the wrong date of 2014-01-01 to 2008-01-01, a watcher that is supposed to
284	fire "after" a second might actually take six years to finally fire.	288	fire "after a second" might actually take six years to finally fire.
285		289
286	AnyEvent cannot compensate for this. The only event loop that is conscious	290	AnyEvent cannot compensate for this. The only event loop that is conscious
287	about these issues is L<EV>, which offers both relative (ev_timer, based	291	of these issues is L<EV>, which offers both relative (ev_timer, based
288	on true relative time) and absolute (ev_periodic, based on wallclock time)	292	on true relative time) and absolute (ev_periodic, based on wallclock time)
289	timers.	293	timers.
290		294
291	AnyEvent always prefers relative timers, if available, matching the	295	AnyEvent always prefers relative timers, if available, matching the
292	AnyEvent API.	296	AnyEvent API.
…		…
314	I<In almost all cases (in all cases if you don't care), this is the	318	I<In almost all cases (in all cases if you don't care), this is the
315	function to call when you want to know the current time.>	319	function to call when you want to know the current time.>
316		320
317	This function is also often faster then C<< AnyEvent->time >>, and	321	This function is also often faster then C<< AnyEvent->time >>, and
318	thus the preferred method if you want some timestamp (for example,	322	thus the preferred method if you want some timestamp (for example,
319	L<AnyEvent::Handle> uses this to update it's activity timeouts).	323	L<AnyEvent::Handle> uses this to update its activity timeouts).
320		324
321	The rest of this section is only of relevance if you try to be very exact	325	The rest of this section is only of relevance if you try to be very exact
322	with your timing, you can skip it without bad conscience.	326	with your timing; you can skip it without a bad conscience.
323		327
324	For a practical example of when these times differ, consider L<Event::Lib>	328	For a practical example of when these times differ, consider L<Event::Lib>
325	and L<EV> and the following set-up:	329	and L<EV> and the following set-up:
326		330
327	The event loop is running and has just invoked one of your callback at	331	The event loop is running and has just invoked one of your callbacks at
328	time=500 (assume no other callbacks delay processing). In your callback,	332	time=500 (assume no other callbacks delay processing). In your callback,
329	you wait a second by executing C<sleep 1> (blocking the process for a	333	you wait a second by executing C<sleep 1> (blocking the process for a
330	second) and then (at time=501) you create a relative timer that fires	334	second) and then (at time=501) you create a relative timer that fires
331	after three seconds.	335	after three seconds.
332		336
…		…
363	might affect timers and time-outs.	367	might affect timers and time-outs.
364		368
365	When this is the case, you can call this method, which will update the	369	When this is the case, you can call this method, which will update the
366	event loop's idea of "current time".	370	event loop's idea of "current time".
367		371
		372	A typical example would be a script in a web server (e.g. C<mod_perl>) -
		373	when mod_perl executes the script, then the event loop will have the wrong
		374	idea about the "current time" (being potentially far in the past, when the
		375	script ran the last time). In that case you should arrange a call to C<<
		376	AnyEvent->now_update >> each time the web server process wakes up again
		377	(e.g. at the start of your script, or in a handler).
		378
368	Note that updating the time I<might> cause some events to be handled.	379	Note that updating the time I<might> cause some events to be handled.
369		380
370	=back	381	=back
371		382
372	=head2 SIGNAL WATCHERS	383	=head2 SIGNAL WATCHERS
…		…
396		407
397	Example: exit on SIGINT	408	Example: exit on SIGINT
398		409
399	my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });	410	my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
400		411
		412	=head3 Restart Behaviour
		413
		414	While restart behaviour is up to the event loop implementation, most will
		415	not restart syscalls (that includes L<Async::Interrupt> and AnyEvent's
		416	pure perl implementation).
		417
		418	=head3 Safe/Unsafe Signals
		419
		420	Perl signals can be either "safe" (synchronous to opcode handling) or
		421	"unsafe" (asynchronous) - the former might get delayed indefinitely, the
		422	latter might corrupt your memory.
		423
		424	AnyEvent signal handlers are, in addition, synchronous to the event loop,
		425	i.e. they will not interrupt your running perl program but will only be
		426	called as part of the normal event handling (just like timer, I/O etc.
		427	callbacks, too).
		428
401	=head3 Signal Races, Delays and Workarounds	429	=head3 Signal Races, Delays and Workarounds
402		430
403	Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching	431	Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching
404	callbacks to signals in a generic way, which is a pity, as you cannot	432	callbacks to signals in a generic way, which is a pity, as you cannot
405	do race-free signal handling in perl, requiring C libraries for	433	do race-free signal handling in perl, requiring C libraries for
406	this. AnyEvent will try to do it's best, which means in some cases,	434	this. AnyEvent will try to do its best, which means in some cases,
407	signals will be delayed. The maximum time a signal might be delayed is	435	signals will be delayed. The maximum time a signal might be delayed is
408	specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This	436	specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This
409	variable can be changed only before the first signal watcher is created,	437	variable can be changed only before the first signal watcher is created,
410	and should be left alone otherwise. This variable determines how often	438	and should be left alone otherwise. This variable determines how often
411	AnyEvent polls for signals (in case a wake-up was missed). Higher values	439	AnyEvent polls for signals (in case a wake-up was missed). Higher values
…		…
413	saving.	441	saving.
414		442
415	All these problems can be avoided by installing the optional	443	All these problems can be avoided by installing the optional
416	L<Async::Interrupt> module, which works with most event loops. It will not	444	L<Async::Interrupt> module, which works with most event loops. It will not
417	work with inherently broken event loops such as L<Event> or L<Event::Lib>	445	work with inherently broken event loops such as L<Event> or L<Event::Lib>
418	(and not with L<POE> currently, as POE does it's own workaround with	446	(and not with L<POE> currently, as POE does its own workaround with
419	one-second latency). For those, you just have to suffer the delays.	447	one-second latency). For those, you just have to suffer the delays.
420		448
421	=head2 CHILD PROCESS WATCHERS	449	=head2 CHILD PROCESS WATCHERS
422		450
423	$w = AnyEvent->child (pid => <process id>, cb => <callback>);	451	$w = AnyEvent->child (pid => <process id>, cb => <callback>);
424		452
425	You can also watch on a child process exit and catch its exit status.	453	You can also watch for a child process exit and catch its exit status.
426		454
427	The child process is specified by the C<pid> argument (one some backends,	455	The child process is specified by the C<pid> argument (on some backends,
428	using C<0> watches for any child process exit, on others this will	456	using C<0> watches for any child process exit, on others this will
429	croak). The watcher will be triggered only when the child process has	457	croak). The watcher will be triggered only when the child process has
430	finished and an exit status is available, not on any trace events	458	finished and an exit status is available, not on any trace events
431	(stopped/continued).	459	(stopped/continued).
432		460
…		…
479		507
480	=head2 IDLE WATCHERS	508	=head2 IDLE WATCHERS
481		509
482	$w = AnyEvent->idle (cb => <callback>);	510	$w = AnyEvent->idle (cb => <callback>);
483		511
484	Sometimes there is a need to do something, but it is not so important	512	This will repeatedly invoke the callback after the process becomes idle,
485	to do it instantly, but only when there is nothing better to do. This	513	until either the watcher is destroyed or new events have been detected.
486	"nothing better to do" is usually defined to be "no other events need
487	attention by the event loop".
488		514
489	Idle watchers ideally get invoked when the event loop has nothing	515	Idle watchers are useful when there is a need to do something, but it
490	better to do, just before it would block the process to wait for new	516	is not so important (or wise) to do it instantly. The callback will be
491	events. Instead of blocking, the idle watcher is invoked.	517	invoked only when there is "nothing better to do", which is usually
		518	defined as "all outstanding events have been handled and no new events
		519	have been detected". That means that idle watchers ideally get invoked
		520	when the event loop has just polled for new events but none have been
		521	detected. Instead of blocking to wait for more events, the idle watchers
		522	will be invoked.
492		523
493	Most event loops unfortunately do not really support idle watchers (only	524	Unfortunately, most event loops do not really support idle watchers (only
494	EV, Event and Glib do it in a usable fashion) - for the rest, AnyEvent	525	EV, Event and Glib do it in a usable fashion) - for the rest, AnyEvent
495	will simply call the callback "from time to time".	526	will simply call the callback "from time to time".
496		527
497	Example: read lines from STDIN, but only process them when the	528	Example: read lines from STDIN, but only process them when the
498	program is otherwise idle:	529	program is otherwise idle:
…		…
526	will actively watch for new events and call your callbacks.	557	will actively watch for new events and call your callbacks.
527		558
528	AnyEvent is slightly different: it expects somebody else to run the event	559	AnyEvent is slightly different: it expects somebody else to run the event
529	loop and will only block when necessary (usually when told by the user).	560	loop and will only block when necessary (usually when told by the user).
530		561
531	The instrument to do that is called a "condition variable", so called	562	The tool to do that is called a "condition variable", so called because
532	because they represent a condition that must become true.	563	they represent a condition that must become true.
533		564
534	Now is probably a good time to look at the examples further below.	565	Now is probably a good time to look at the examples further below.
535		566
536	Condition variables can be created by calling the C<< AnyEvent->condvar	567	Condition variables can be created by calling the C<< AnyEvent->condvar
537	>> method, usually without arguments. The only argument pair allowed is	568	>> method, usually without arguments. The only argument pair allowed is
…		…
542	After creation, the condition variable is "false" until it becomes "true"	573	After creation, the condition variable is "false" until it becomes "true"
543	by calling the C<send> method (or calling the condition variable as if it	574	by calling the C<send> method (or calling the condition variable as if it
544	were a callback, read about the caveats in the description for the C<<	575	were a callback, read about the caveats in the description for the C<<
545	->send >> method).	576	->send >> method).
546		577
547	Condition variables are similar to callbacks, except that you can	578	Since condition variables are the most complex part of the AnyEvent API, here are
548	optionally wait for them. They can also be called merge points - points	579	some different mental models of what they are - pick the ones you can connect to:
549	in time where multiple outstanding events have been processed. And yet	580
550	another way to call them is transactions - each condition variable can be	581	=over 4
551	used to represent a transaction, which finishes at some point and delivers	582
552	a result. And yet some people know them as "futures" - a promise to	583	=item * Condition variables are like callbacks - you can call them (and pass them instead
553	compute/deliver something that you can wait for.	584	of callbacks). Unlike callbacks however, you can also wait for them to be called.
		585
		586	=item * Condition variables are signals - one side can emit or send them,
		587	the other side can wait for them, or install a handler that is called when
		588	the signal fires.
		589
		590	=item * Condition variables are like "Merge Points" - points in your program
		591	where you merge multiple independent results/control flows into one.
		592
		593	=item * Condition variables represent a transaction - functions that start
		594	some kind of transaction can return them, leaving the caller the choice
		595	between waiting in a blocking fashion, or setting a callback.
		596
		597	=item * Condition variables represent future values, or promises to deliver
		598	some result, long before the result is available.
		599
		600	=back
554		601
555	Condition variables are very useful to signal that something has finished,	602	Condition variables are very useful to signal that something has finished,
556	for example, if you write a module that does asynchronous http requests,	603	for example, if you write a module that does asynchronous http requests,
557	then a condition variable would be the ideal candidate to signal the	604	then a condition variable would be the ideal candidate to signal the
558	availability of results. The user can either act when the callback is	605	availability of results. The user can either act when the callback is
…		…
571		618
572	Condition variables are represented by hash refs in perl, and the keys	619	Condition variables are represented by hash refs in perl, and the keys
573	used by AnyEvent itself are all named C<_ae_XXX> to make subclassing	620	used by AnyEvent itself are all named C<_ae_XXX> to make subclassing
574	easy (it is often useful to build your own transaction class on top of	621	easy (it is often useful to build your own transaction class on top of
575	AnyEvent). To subclass, use C<AnyEvent::CondVar> as base class and call	622	AnyEvent). To subclass, use C<AnyEvent::CondVar> as base class and call
576	it's C<new> method in your own C<new> method.	623	its C<new> method in your own C<new> method.
577		624
578	There are two "sides" to a condition variable - the "producer side" which	625	There are two "sides" to a condition variable - the "producer side" which
579	eventually calls C<< -> send >>, and the "consumer side", which waits	626	eventually calls C<< -> send >>, and the "consumer side", which waits
580	for the send to occur.	627	for the send to occur.
581		628
582	Example: wait for a timer.	629	Example: wait for a timer.
583		630
584	# wait till the result is ready	631	# condition: "wait till the timer is fired"
585	my $result_ready = AnyEvent->condvar;	632	my $timer_fired = AnyEvent->condvar;
586		633
587	# do something such as adding a timer	634	# create the timer - we could wait for, say
588	# or socket watcher the calls $result_ready->send	635	# a handle becomign ready, or even an
589	# when the "result" is ready.	636	# AnyEvent::HTTP request to finish, but
590	# in this case, we simply use a timer:	637	# in this case, we simply use a timer:
591	my $w = AnyEvent->timer (	638	my $w = AnyEvent->timer (
592	after => 1,	639	after => 1,
593	cb => sub { $result_ready->send },	640	cb => sub { $timer_fired->send },
594	);	641	);
595		642
596	# this "blocks" (while handling events) till the callback	643	# this "blocks" (while handling events) till the callback
597	# calls -<send	644	# calls ->send
598	$result_ready->recv;	645	$timer_fired->recv;
599		646
600	Example: wait for a timer, but take advantage of the fact that condition	647	Example: wait for a timer, but take advantage of the fact that condition
601	variables are also callable directly.	648	variables are also callable directly.
602		649
603	my $done = AnyEvent->condvar;	650	my $done = AnyEvent->condvar;
…		…
646	they were a code reference). Calling them directly is the same as calling	693	they were a code reference). Calling them directly is the same as calling
647	C<send>.	694	C<send>.
648		695
649	=item $cv->croak ($error)	696	=item $cv->croak ($error)
650		697
651	Similar to send, but causes all call's to C<< ->recv >> to invoke	698	Similar to send, but causes all calls to C<< ->recv >> to invoke
652	C<Carp::croak> with the given error message/object/scalar.	699	C<Carp::croak> with the given error message/object/scalar.
653		700
654	This can be used to signal any errors to the condition variable	701	This can be used to signal any errors to the condition variable
655	user/consumer. Doing it this way instead of calling C<croak> directly	702	user/consumer. Doing it this way instead of calling C<croak> directly
656	delays the error detetcion, but has the overwhelmign advantage that it	703	delays the error detection, but has the overwhelming advantage that it
657	diagnoses the error at the place where the result is expected, and not	704	diagnoses the error at the place where the result is expected, and not
658	deep in some event clalback without connection to the actual code causing	705	deep in some event callback with no connection to the actual code causing
659	the problem.	706	the problem.
660		707
661	=item $cv->begin ([group callback])	708	=item $cv->begin ([group callback])
662		709
663	=item $cv->end	710	=item $cv->end
…		…
701	one call to C<begin>, so the condvar waits for all calls to C<end> before	748	one call to C<begin>, so the condvar waits for all calls to C<end> before
702	sending.	749	sending.
703		750
704	The ping example mentioned above is slightly more complicated, as the	751	The ping example mentioned above is slightly more complicated, as the
705	there are results to be passwd back, and the number of tasks that are	752	there are results to be passwd back, and the number of tasks that are
706	begung can potentially be zero:	753	begun can potentially be zero:
707		754
708	my $cv = AnyEvent->condvar;	755	my $cv = AnyEvent->condvar;
709		756
710	my %result;	757	my %result;
711	$cv->begin (sub { shift->send (\%result) });	758	$cv->begin (sub { shift->send (\%result) });
…		…
732	to be called once the counter reaches C<0>, and second, it ensures that	779	to be called once the counter reaches C<0>, and second, it ensures that
733	C<send> is called even when C<no> hosts are being pinged (the loop	780	C<send> is called even when C<no> hosts are being pinged (the loop
734	doesn't execute once).	781	doesn't execute once).
735		782
736	This is the general pattern when you "fan out" into multiple (but	783	This is the general pattern when you "fan out" into multiple (but
737	potentially none) subrequests: use an outer C<begin>/C<end> pair to set	784	potentially zero) subrequests: use an outer C<begin>/C<end> pair to set
738	the callback and ensure C<end> is called at least once, and then, for each	785	the callback and ensure C<end> is called at least once, and then, for each
739	subrequest you start, call C<begin> and for each subrequest you finish,	786	subrequest you start, call C<begin> and for each subrequest you finish,
740	call C<end>.	787	call C<end>.
741		788
742	=back	789	=back
…		…
749	=over 4	796	=over 4
750		797
751	=item $cv->recv	798	=item $cv->recv
752		799
753	Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak	800	Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak
754	>> methods have been called on c<$cv>, while servicing other watchers	801	>> methods have been called on C<$cv>, while servicing other watchers
755	normally.	802	normally.
756		803
757	You can only wait once on a condition - additional calls are valid but	804	You can only wait once on a condition - additional calls are valid but
758	will return immediately.	805	will return immediately.
759		806
…		…
776	caller decide whether the call will block or not (for example, by coupling	823	caller decide whether the call will block or not (for example, by coupling
777	condition variables with some kind of request results and supporting	824	condition variables with some kind of request results and supporting
778	callbacks so the caller knows that getting the result will not block,	825	callbacks so the caller knows that getting the result will not block,
779	while still supporting blocking waits if the caller so desires).	826	while still supporting blocking waits if the caller so desires).
780		827
781	You can ensure that C<< -recv >> never blocks by setting a callback and	828	You can ensure that C<< ->recv >> never blocks by setting a callback and
782	only calling C<< ->recv >> from within that callback (or at a later	829	only calling C<< ->recv >> from within that callback (or at a later
783	time). This will work even when the event loop does not support blocking	830	time). This will work even when the event loop does not support blocking
784	waits otherwise.	831	waits otherwise.
785		832
786	=item $bool = $cv->ready	833	=item $bool = $cv->ready
…		…
791	=item $cb = $cv->cb ($cb->($cv))	838	=item $cb = $cv->cb ($cb->($cv))
792		839
793	This is a mutator function that returns the callback set and optionally	840	This is a mutator function that returns the callback set and optionally
794	replaces it before doing so.	841	replaces it before doing so.
795		842
796	The callback will be called when the condition becomes (or already was)	843	The callback will be called when the condition becomes "true", i.e. when
797	"true", i.e. when C<send> or C<croak> are called (or were called), with	844	C<send> or C<croak> are called, with the only argument being the
798	the only argument being the condition variable itself. Calling C<recv>	845	condition variable itself. If the condition is already true, the
		846	callback is called immediately when it is set. Calling C<recv> inside
799	inside the callback or at any later time is guaranteed not to block.	847	the callback or at any later time is guaranteed not to block.
800		848
801	=back	849	=back
802		850
803	=head1 SUPPORTED EVENT LOOPS/BACKENDS	851	=head1 SUPPORTED EVENT LOOPS/BACKENDS
804		852
…		…
816	AnyEvent::Impl::EV based on EV (interface to libev, best choice).	864	AnyEvent::Impl::EV based on EV (interface to libev, best choice).
817	AnyEvent::Impl::Perl pure-perl implementation, fast and portable.	865	AnyEvent::Impl::Perl pure-perl implementation, fast and portable.
818		866
819	=item Backends that are transparently being picked up when they are used.	867	=item Backends that are transparently being picked up when they are used.
820		868
821	These will be used when they are currently loaded when the first watcher	869	These will be used if they are already loaded when the first watcher
822	is created, in which case it is assumed that the application is using	870	is created, in which case it is assumed that the application is using
823	them. This means that AnyEvent will automatically pick the right backend	871	them. This means that AnyEvent will automatically pick the right backend
824	when the main program loads an event module before anything starts to	872	when the main program loads an event module before anything starts to
825	create watchers. Nothing special needs to be done by the main program.	873	create watchers. Nothing special needs to be done by the main program.
826		874
…		…
828	AnyEvent::Impl::Glib based on Glib, slow but very stable.	876	AnyEvent::Impl::Glib based on Glib, slow but very stable.
829	AnyEvent::Impl::Tk based on Tk, very broken.	877	AnyEvent::Impl::Tk based on Tk, very broken.
830	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.	878	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
831	AnyEvent::Impl::POE based on POE, very slow, some limitations.	879	AnyEvent::Impl::POE based on POE, very slow, some limitations.
832	AnyEvent::Impl::Irssi used when running within irssi.	880	AnyEvent::Impl::Irssi used when running within irssi.
		881	AnyEvent::Impl::IOAsync based on IO::Async.
		882	AnyEvent::Impl::Cocoa based on Cocoa::EventLoop.
833		883
834	=item Backends with special needs.	884	=item Backends with special needs.
835		885
836	Qt requires the Qt::Application to be instantiated first, but will	886	Qt requires the Qt::Application to be instantiated first, but will
837	otherwise be picked up automatically. As long as the main program	887	otherwise be picked up automatically. As long as the main program
838	instantiates the application before any AnyEvent watchers are created,	888	instantiates the application before any AnyEvent watchers are created,
839	everything should just work.	889	everything should just work.
840		890
841	AnyEvent::Impl::Qt based on Qt.	891	AnyEvent::Impl::Qt based on Qt.
842		892
843	Support for IO::Async can only be partial, as it is too broken and
844	architecturally limited to even support the AnyEvent API. It also
845	is the only event loop that needs the loop to be set explicitly, so
846	it can only be used by a main program knowing about AnyEvent. See
847	L<AnyEvent::Impl::Async> for the gory details.
848
849	AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed.
850
851	=item Event loops that are indirectly supported via other backends.	893	=item Event loops that are indirectly supported via other backends.
852		894
853	Some event loops can be supported via other modules:	895	Some event loops can be supported via other modules:
854		896
855	There is no direct support for WxWidgets (L<Wx>) or L<Prima>.	897	There is no direct support for WxWidgets (L<Wx>) or L<Prima>.
…		…
880	Contains C<undef> until the first watcher is being created, before the	922	Contains C<undef> until the first watcher is being created, before the
881	backend has been autodetected.	923	backend has been autodetected.
882		924
883	Afterwards it contains the event model that is being used, which is the	925	Afterwards it contains the event model that is being used, which is the
884	name of the Perl class implementing the model. This class is usually one	926	name of the Perl class implementing the model. This class is usually one
885	of the C<AnyEvent::Impl:xxx> modules, but can be any other class in the	927	of the C<AnyEvent::Impl::xxx> modules, but can be any other class in the
886	case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it	928	case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it
887	will be C<urxvt::anyevent>).	929	will be C<urxvt::anyevent>).
888		930
889	=item AnyEvent::detect	931	=item AnyEvent::detect
890		932
891	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model	933	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model
892	if necessary. You should only call this function right before you would	934	if necessary. You should only call this function right before you would
893	have created an AnyEvent watcher anyway, that is, as late as possible at	935	have created an AnyEvent watcher anyway, that is, as late as possible at
894	runtime, and not e.g. while initialising of your module.	936	runtime, and not e.g. during initialisation of your module.
895		937
896	If you need to do some initialisation before AnyEvent watchers are	938	If you need to do some initialisation before AnyEvent watchers are
897	created, use C<post_detect>.	939	created, use C<post_detect>.
898		940
899	=item $guard = AnyEvent::post_detect { BLOCK }	941	=item $guard = AnyEvent::post_detect { BLOCK }
900		942
901	Arranges for the code block to be executed as soon as the event model is	943	Arranges for the code block to be executed as soon as the event model is
902	autodetected (or immediately if this has already happened).	944	autodetected (or immediately if that has already happened).
903		945
904	The block will be executed I<after> the actual backend has been detected	946	The block will be executed I<after> the actual backend has been detected
905	(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been	947	(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been
906	created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do	948	created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do
907	other initialisations - see the sources of L<AnyEvent::Strict> or	949	other initialisations - see the sources of L<AnyEvent::Strict> or
…		…
916	that automatically removes the callback again when it is destroyed (or	958	that automatically removes the callback again when it is destroyed (or
917	C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for	959	C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for
918	a case where this is useful.	960	a case where this is useful.
919		961
920	Example: Create a watcher for the IO::AIO module and store it in	962	Example: Create a watcher for the IO::AIO module and store it in
921	C<$WATCHER>. Only do so after the event loop is initialised, though.	963	C<$WATCHER>, but do so only do so after the event loop is initialised.
922		964
923	our WATCHER;	965	our WATCHER;
924		966
925	my $guard = AnyEvent::post_detect {	967	my $guard = AnyEvent::post_detect {
926	$WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb);	968	$WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb);
…		…
934	$WATCHER ||= $guard;	976	$WATCHER ||= $guard;
935		977
936	=item @AnyEvent::post_detect	978	=item @AnyEvent::post_detect
937		979
938	If there are any code references in this array (you can C<push> to it	980	If there are any code references in this array (you can C<push> to it
939	before or after loading AnyEvent), then they will called directly after	981	before or after loading AnyEvent), then they will be called directly
940	the event loop has been chosen.	982	after the event loop has been chosen.
941		983
942	You should check C<$AnyEvent::MODEL> before adding to this array, though:	984	You should check C<$AnyEvent::MODEL> before adding to this array, though:
943	if it is defined then the event loop has already been detected, and the	985	if it is defined then the event loop has already been detected, and the
944	array will be ignored.	986	array will be ignored.
945		987
946	Best use C<AnyEvent::post_detect { BLOCK }> when your application allows	988	Best use C<AnyEvent::post_detect { BLOCK }> when your application allows
947	it,as it takes care of these details.	989	it, as it takes care of these details.
948		990
949	This variable is mainly useful for modules that can do something useful	991	This variable is mainly useful for modules that can do something useful
950	when AnyEvent is used and thus want to know when it is initialised, but do	992	when AnyEvent is used and thus want to know when it is initialised, but do
951	not need to even load it by default. This array provides the means to hook	993	not need to even load it by default. This array provides the means to hook
952	into AnyEvent passively, without loading it.	994	into AnyEvent passively, without loading it.
953		995
		996	Example: To load Coro::AnyEvent whenever Coro and AnyEvent are used
		997	together, you could put this into Coro (this is the actual code used by
		998	Coro to accomplish this):
		999
		1000	if (defined $AnyEvent::MODEL) {
		1001	# AnyEvent already initialised, so load Coro::AnyEvent
		1002	require Coro::AnyEvent;
		1003	} else {
		1004	# AnyEvent not yet initialised, so make sure to load Coro::AnyEvent
		1005	# as soon as it is
		1006	push @AnyEvent::post_detect, sub { require Coro::AnyEvent };
		1007	}
		1008
954	=back	1009	=back
955		1010
956	=head1 WHAT TO DO IN A MODULE	1011	=head1 WHAT TO DO IN A MODULE
957		1012
958	As a module author, you should C<use AnyEvent> and call AnyEvent methods	1013	As a module author, you should C<use AnyEvent> and call AnyEvent methods
…		…
968	because it will stall the whole program, and the whole point of using	1023	because it will stall the whole program, and the whole point of using
969	events is to stay interactive.	1024	events is to stay interactive.
970		1025
971	It is fine, however, to call C<< ->recv >> when the user of your module	1026	It is fine, however, to call C<< ->recv >> when the user of your module
972	requests it (i.e. if you create a http request object ad have a method	1027	requests it (i.e. if you create a http request object ad have a method
973	called C<results> that returns the results, it should call C<< ->recv >>	1028	called C<results> that returns the results, it may call C<< ->recv >>
974	freely, as the user of your module knows what she is doing. always).	1029	freely, as the user of your module knows what she is doing. Always).
975		1030
976	=head1 WHAT TO DO IN THE MAIN PROGRAM	1031	=head1 WHAT TO DO IN THE MAIN PROGRAM
977		1032
978	There will always be a single main program - the only place that should	1033	There will always be a single main program - the only place that should
979	dictate which event model to use.	1034	dictate which event model to use.
980		1035
981	If it doesn't care, it can just "use AnyEvent" and use it itself, or not	1036	If the program is not event-based, it need not do anything special, even
982	do anything special (it does not need to be event-based) and let AnyEvent	1037	when it depends on a module that uses an AnyEvent. If the program itself
983	decide which implementation to chose if some module relies on it.	1038	uses AnyEvent, but does not care which event loop is used, all it needs
		1039	to do is C<use AnyEvent>. In either case, AnyEvent will choose the best
		1040	available loop implementation.
984		1041
985	If the main program relies on a specific event model - for example, in	1042	If the main program relies on a specific event model - for example, in
986	Gtk2 programs you have to rely on the Glib module - you should load the	1043	Gtk2 programs you have to rely on the Glib module - you should load the
987	event module before loading AnyEvent or any module that uses it: generally	1044	event module before loading AnyEvent or any module that uses it: generally
988	speaking, you should load it as early as possible. The reason is that	1045	speaking, you should load it as early as possible. The reason is that
989	modules might create watchers when they are loaded, and AnyEvent will	1046	modules might create watchers when they are loaded, and AnyEvent will
990	decide on the event model to use as soon as it creates watchers, and it	1047	decide on the event model to use as soon as it creates watchers, and it
991	might chose the wrong one unless you load the correct one yourself.	1048	might choose the wrong one unless you load the correct one yourself.
992		1049
993	You can chose to use a pure-perl implementation by loading the	1050	You can chose to use a pure-perl implementation by loading the
994	C<AnyEvent::Impl::Perl> module, which gives you similar behaviour	1051	C<AnyEvent::Impl::Perl> module, which gives you similar behaviour
995	everywhere, but letting AnyEvent chose the model is generally better.	1052	everywhere, but letting AnyEvent chose the model is generally better.
996		1053
…		…
1014	=head1 OTHER MODULES	1071	=head1 OTHER MODULES
1015		1072
1016	The following is a non-exhaustive list of additional modules that use	1073	The following is a non-exhaustive list of additional modules that use
1017	AnyEvent as a client and can therefore be mixed easily with other AnyEvent	1074	AnyEvent as a client and can therefore be mixed easily with other AnyEvent
1018	modules and other event loops in the same program. Some of the modules	1075	modules and other event loops in the same program. Some of the modules
1019	come with AnyEvent, most are available via CPAN.	1076	come as part of AnyEvent, the others are available via CPAN.
1020		1077
1021	=over 4	1078	=over 4
1022		1079
1023	=item L<AnyEvent::Util>	1080	=item L<AnyEvent::Util>
1024		1081
1025	Contains various utility functions that replace often-used but blocking	1082	Contains various utility functions that replace often-used blocking
1026	functions such as C<inet_aton> by event-/callback-based versions.	1083	functions such as C<inet_aton> with event/callback-based versions.
1027		1084
1028	=item L<AnyEvent::Socket>	1085	=item L<AnyEvent::Socket>
1029		1086
1030	Provides various utility functions for (internet protocol) sockets,	1087	Provides various utility functions for (internet protocol) sockets,
1031	addresses and name resolution. Also functions to create non-blocking tcp	1088	addresses and name resolution. Also functions to create non-blocking tcp
…		…
1033		1090
1034	=item L<AnyEvent::Handle>	1091	=item L<AnyEvent::Handle>
1035		1092
1036	Provide read and write buffers, manages watchers for reads and writes,	1093	Provide read and write buffers, manages watchers for reads and writes,
1037	supports raw and formatted I/O, I/O queued and fully transparent and	1094	supports raw and formatted I/O, I/O queued and fully transparent and
1038	non-blocking SSL/TLS (via L<AnyEvent::TLS>.	1095	non-blocking SSL/TLS (via L<AnyEvent::TLS>).
1039		1096
1040	=item L<AnyEvent::DNS>	1097	=item L<AnyEvent::DNS>
1041		1098
1042	Provides rich asynchronous DNS resolver capabilities.	1099	Provides rich asynchronous DNS resolver capabilities.
1043		1100
		1101	=item L<AnyEvent::HTTP>, L<AnyEvent::IRC>, L<AnyEvent::XMPP>, L<AnyEvent::GPSD>, L<AnyEvent::IGS>, L<AnyEvent::FCP>
		1102
		1103	Implement event-based interfaces to the protocols of the same name (for
		1104	the curious, IGS is the International Go Server and FCP is the Freenet
		1105	Client Protocol).
		1106
		1107	=item L<AnyEvent::Handle::UDP>
		1108
		1109	Here be danger!
		1110
		1111	As Pauli would put it, "Not only is it not right, it's not even wrong!" -
		1112	there are so many things wrong with AnyEvent::Handle::UDP, most notably
		1113	its use of a stream-based API with a protocol that isn't streamable, that
		1114	the only way to improve it is to delete it.
		1115
		1116	It features data corruption (but typically only under load) and general
		1117	confusion. On top, the author is not only clueless about UDP but also
		1118	fact-resistant - some gems of his understanding: "connect doesn't work
		1119	with UDP", "UDP packets are not IP packets", "UDP only has datagrams, not
		1120	packets", "I don't need to implement proper error checking as UDP doesn't
		1121	support error checking" and so on - he doesn't even understand what's
		1122	wrong with his module when it is explained to him.
		1123
1044	=item L<AnyEvent::HTTP>	1124	=item L<AnyEvent::DBI>
1045		1125
1046	A simple-to-use HTTP library that is capable of making a lot of concurrent	1126	Executes L<DBI> requests asynchronously in a proxy process for you,
1047	HTTP requests.	1127	notifying you in an event-based way when the operation is finished.
		1128
		1129	=item L<AnyEvent::AIO>
		1130
		1131	Truly asynchronous (as opposed to non-blocking) I/O, should be in the
		1132	toolbox of every event programmer. AnyEvent::AIO transparently fuses
		1133	L<IO::AIO> and AnyEvent together, giving AnyEvent access to event-based
		1134	file I/O, and much more.
1048		1135
1049	=item L<AnyEvent::HTTPD>	1136	=item L<AnyEvent::HTTPD>
1050		1137
1051	Provides a simple web application server framework.	1138	A simple embedded webserver.
1052		1139
1053	=item L<AnyEvent::FastPing>	1140	=item L<AnyEvent::FastPing>
1054		1141
1055	The fastest ping in the west.	1142	The fastest ping in the west.
1056
1057	=item L<AnyEvent::DBI>
1058
1059	Executes L<DBI> requests asynchronously in a proxy process.
1060
1061	=item L<AnyEvent::AIO>
1062
1063	Truly asynchronous I/O, should be in the toolbox of every event
1064	programmer. AnyEvent::AIO transparently fuses L<IO::AIO> and AnyEvent
1065	together.
1066
1067	=item L<AnyEvent::BDB>
1068
1069	Truly asynchronous Berkeley DB access. AnyEvent::BDB transparently fuses
1070	L<BDB> and AnyEvent together.
1071
1072	=item L<AnyEvent::GPSD>
1073
1074	A non-blocking interface to gpsd, a daemon delivering GPS information.
1075
1076	=item L<AnyEvent::IRC>
1077
1078	AnyEvent based IRC client module family (replacing the older Net::IRC3).
1079
1080	=item L<AnyEvent::XMPP>
1081
1082	AnyEvent based XMPP (Jabber protocol) module family (replacing the older
1083	Net::XMPP2>.
1084
1085	=item L<AnyEvent::IGS>
1086
1087	A non-blocking interface to the Internet Go Server protocol (used by
1088	L<App::IGS>).
1089
1090	=item L<Net::FCP>
1091
1092	AnyEvent-based implementation of the Freenet Client Protocol, birthplace
1093	of AnyEvent.
1094
1095	=item L<Event::ExecFlow>
1096
1097	High level API for event-based execution flow control.
1098		1143
1099	=item L<Coro>	1144	=item L<Coro>
1100		1145
1101	Has special support for AnyEvent via L<Coro::AnyEvent>.	1146	Has special support for AnyEvent via L<Coro::AnyEvent>.
1102		1147
…		…
1106		1151
1107	package AnyEvent;	1152	package AnyEvent;
1108		1153
1109	# basically a tuned-down version of common::sense	1154	# basically a tuned-down version of common::sense
1110	sub common_sense {	1155	sub common_sense {
1111	# no warnings	1156	# from common:.sense 3.3
1112	${^WARNING_BITS} ^= ${^WARNING_BITS};	1157	${^WARNING_BITS} ^= ${^WARNING_BITS} ^ "\x3c\x3f\x33\x00\x0f\xf3\x0f\xc0\xf0\xfc\x33\x00";
1113	# use strict vars subs	1158	# use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl)
1114	$^H |= 0x00000600;	1159	$^H |= 0x00000600;
1115	}	1160	}
1116		1161
1117	BEGIN { AnyEvent::common_sense }	1162	BEGIN { AnyEvent::common_sense }
1118		1163
1119	use Carp ();	1164	use Carp ();
1120		1165
1121	our $VERSION = '5.11';	1166	our $VERSION = '5.3';
1122	our $MODEL;	1167	our $MODEL;
1123		1168
1124	our $AUTOLOAD;	1169	our $AUTOLOAD;
1125	our @ISA;	1170	our @ISA;
1126		1171
1127	our @REGISTRY;	1172	our @REGISTRY;
1128		1173
1129	our $WIN32;
1130
1131	our $VERBOSE;	1174	our $VERBOSE;
1132		1175
1133	BEGIN {	1176	BEGIN {
1134	eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }";	1177	require "AnyEvent/constants.pl";
		1178
1135	eval "sub TAINT(){ " . (${^TAINT}*1) . " }";	1179	eval "sub TAINT (){" . (${^TAINT}*1) . "}";
1136		1180
1137	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}	1181	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}
1138	if ${^TAINT};	1182	if ${^TAINT};
1139		1183
1140	$VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1;	1184	$VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1;
…		…
1165	[Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles	1209	[Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
1166	[Qt:: => AnyEvent::Impl::Qt::], # requires special main program	1210	[Qt:: => AnyEvent::Impl::Qt::], # requires special main program
1167	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza	1211	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
1168	[Wx:: => AnyEvent::Impl::POE::],	1212	[Wx:: => AnyEvent::Impl::POE::],
1169	[Prima:: => AnyEvent::Impl::POE::],	1213	[Prima:: => AnyEvent::Impl::POE::],
1170	# IO::Async is just too broken - we would need workarounds for its
1171	# byzantine signal and broken child handling, among others.
1172	# IO::Async is rather hard to detect, as it doesn't have any
1173	# obvious default class.
1174	[IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program
1175	[IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program	1214	[IO::Async::Loop:: => AnyEvent::Impl::IOAsync::],
1176	[IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program	1215	[Cocoa::EventLoop:: => AnyEvent::Impl::Cocoa::],
1177	[AnyEvent::Impl::IOAsync:: => AnyEvent::Impl::IOAsync::], # requires special main program
1178	);	1216	);
1179		1217
1180	our %method = map +($_ => 1),	1218	our %method = map +($_ => 1),
1181	qw(io timer time now now_update signal child idle condvar one_event DESTROY);	1219	qw(io timer time now now_update signal child idle condvar one_event DESTROY);
1182		1220
1183	our @post_detect;	1221	our @post_detect;
1184		1222
1185	sub post_detect(&) {	1223	sub post_detect(&) {
1186	my ($cb) = @_;	1224	my ($cb) = @_;
1187		1225
1188	if ($MODEL) {
1189	$cb->();
1190
1191	undef
1192	} else {
1193	push @post_detect, $cb;	1226	push @post_detect, $cb;
1194		1227
1195	defined wantarray	1228	defined wantarray
1196	? bless \$cb, "AnyEvent::Util::postdetect"	1229	? bless \$cb, "AnyEvent::Util::postdetect"
1197	: ()	1230	: ()
1198	}
1199	}	1231	}
1200		1232
1201	sub AnyEvent::Util::postdetect::DESTROY {	1233	sub AnyEvent::Util::postdetect::DESTROY {
1202	@post_detect = grep $_ != ${$_[0]}, @post_detect;	1234	@post_detect = grep $_ != ${$_[0]}, @post_detect;
1203	}	1235	}
1204		1236
1205	sub detect() {	1237	sub detect() {
		1238	# free some memory
		1239	*detect = sub () { $MODEL };
		1240
		1241	local $!; # for good measure
		1242	local $SIG{__DIE__};
		1243
		1244	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {
		1245	my $model = "AnyEvent::Impl::$1";
		1246	if (eval "require $model") {
		1247	$MODEL = $model;
		1248	warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2;
		1249	} else {
		1250	warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE;
		1251	}
		1252	}
		1253
		1254	# check for already loaded models
1206	unless ($MODEL) {	1255	unless ($MODEL) {
1207	local $SIG{__DIE__};	1256	for (@REGISTRY, @models) {
1208		1257	my ($package, $model) = @$_;
1209	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {	1258	if (${"$package\::VERSION"} > 0) {
1210	my $model = "AnyEvent::Impl::$1";
1211	if (eval "require $model") {	1259	if (eval "require $model") {
1212	$MODEL = $model;	1260	$MODEL = $model;
1213	warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2;	1261	warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2;
1214	} else {	1262	last;
1215	warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE;	1263	}
1216	}	1264	}
1217	}	1265	}
1218		1266
1219	# check for already loaded models
1220	unless ($MODEL) {	1267	unless ($MODEL) {
		1268	# try to autoload a model
1221	for (@REGISTRY, @models) {	1269	for (@REGISTRY, @models) {
1222	my ($package, $model) = @$_;	1270	my ($package, $model, $autoload) = @$_;
		1271	if (
		1272	$autoload
		1273	and eval "require $package"
1223	if (${"$package\::VERSION"} > 0) {	1274	and ${"$package\::VERSION"} > 0
1224	if (eval "require $model") {	1275	and eval "require $model"
		1276	) {
1225	$MODEL = $model;	1277	$MODEL = $model;
1226	warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2;	1278	warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2;
1227	last;	1279	last;
1228	}
1229	}	1280	}
1230	}	1281	}
1231		1282
1232	unless ($MODEL) {
1233	# try to autoload a model
1234	for (@REGISTRY, @models) {
1235	my ($package, $model, $autoload) = @$_;
1236	if (
1237	$autoload
1238	and eval "require $package"
1239	and ${"$package\::VERSION"} > 0
1240	and eval "require $model"
1241	) {
1242	$MODEL = $model;
1243	warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2;
1244	last;
1245	}
1246	}
1247
1248	$MODEL	1283	$MODEL
1249	or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.\n";	1284	or die "AnyEvent: backend autodetection failed - did you properly install AnyEvent?\n";
1250	}
1251	}	1285	}
1252
1253	push @{"$MODEL\::ISA"}, "AnyEvent::Base";
1254
1255	unshift @ISA, $MODEL;
1256
1257	require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT};
1258
1259	(shift @post_detect)->() while @post_detect;
1260	}	1286	}
		1287
		1288	@models = (); # free probe data
		1289
		1290	push @{"$MODEL\::ISA"}, "AnyEvent::Base";
		1291	unshift @ISA, $MODEL;
		1292
		1293	# now nuke some methods that are overridden by the backend.
		1294	# SUPER is not allowed.
		1295	for (qw(time signal child idle)) {
		1296	undef &{"AnyEvent::Base::$_"}
		1297	if defined &{"$MODEL\::$_"};
		1298	}
		1299
		1300	if ($ENV{PERL_ANYEVENT_STRICT}) {
		1301	eval { require AnyEvent::Strict };
		1302	warn "AnyEvent: cannot load AnyEvent::Strict: $@"
		1303	if $@ && $VERBOSE;
		1304	}
		1305
		1306	(shift @post_detect)->() while @post_detect;
		1307
		1308	*post_detect = sub(&) {
		1309	shift->();
		1310
		1311	undef
		1312	};
1261		1313
1262	$MODEL	1314	$MODEL
1263	}	1315	}
1264		1316
1265	sub AUTOLOAD {	1317	sub AUTOLOAD {
1266	(my $func = $AUTOLOAD) =~ s/.*://;	1318	(my $func = $AUTOLOAD) =~ s/.*://;
1267		1319
1268	$method{$func}	1320	$method{$func}
1269	or Carp::croak "$func: not a valid method for AnyEvent objects";	1321	or Carp::croak "$func: not a valid AnyEvent class method";
1270		1322
1271	detect unless $MODEL;	1323	detect;
1272		1324
1273	my $class = shift;	1325	my $class = shift;
1274	$class->$func (@_);	1326	$class->$func (@_);
1275	}	1327	}
1276		1328
…		…
1293		1345
1294	=head1 SIMPLIFIED AE API	1346	=head1 SIMPLIFIED AE API
1295		1347
1296	Starting with version 5.0, AnyEvent officially supports a second, much	1348	Starting with version 5.0, AnyEvent officially supports a second, much
1297	simpler, API that is designed to reduce the calling, typing and memory	1349	simpler, API that is designed to reduce the calling, typing and memory
1298	overhead.	1350	overhead by using function call syntax and a fixed number of parameters.
1299		1351
1300	See the L<AE> manpage for details.	1352	See the L<AE> manpage for details.
1301		1353
1302	=cut	1354	=cut
1303		1355
1304	package AE;	1356	package AE;
1305		1357
1306	our $VERSION = $AnyEvent::VERSION;	1358	our $VERSION = $AnyEvent::VERSION;
		1359
		1360	# fall back to the main API by default - backends and AnyEvent::Base
		1361	# implementations can overwrite these.
1307		1362
1308	sub io($$$) {	1363	sub io($$$) {
1309	AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])	1364	AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])
1310	}	1365	}
1311		1366
…		…
1343		1398
1344	package AnyEvent::Base;	1399	package AnyEvent::Base;
1345		1400
1346	# default implementations for many methods	1401	# default implementations for many methods
1347		1402
1348	sub _time {	1403	sub time {
		1404	eval q{ # poor man's autoloading {}
1349	# probe for availability of Time::HiRes	1405	# probe for availability of Time::HiRes
1350	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {	1406	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
1351	warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8;	1407	warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8;
1352	*_time = \&Time::HiRes::time;	1408	*AE::time = \&Time::HiRes::time;
1353	# if (eval "use POSIX (); (POSIX::times())...	1409	# if (eval "use POSIX (); (POSIX::times())...
1354	} else {	1410	} else {
1355	warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE;	1411	warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE;
1356	*_time = sub { time }; # epic fail	1412	*AE::time = sub (){ time }; # epic fail
		1413	}
		1414
		1415	*time = sub { AE::time }; # different prototypes
1357	}	1416	};
		1417	die if $@;
1358		1418
1359	&_time	1419	&time
1360	}	1420	}
1361		1421
1362	sub time { _time }	1422	*now = \&time;
1363	sub now { _time }	1423
1364	sub now_update { }	1424	sub now_update { }
1365		1425
1366	# default implementation for ->condvar	1426	# default implementation for ->condvar
1367		1427
1368	sub condvar {	1428	sub condvar {
		1429	eval q{ # poor man's autoloading {}
		1430	*condvar = sub {
1369	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"	1431	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"
		1432	};
		1433
		1434	*AE::cv = sub (;&) {
		1435	bless { @_ ? (_ae_cb => shift) : () }, "AnyEvent::CondVar"
		1436	};
		1437	};
		1438	die if $@;
		1439
		1440	&condvar
1370	}	1441	}
1371		1442
1372	# default implementation for ->signal	1443	# default implementation for ->signal
1373		1444
1374	our $HAVE_ASYNC_INTERRUPT;	1445	our $HAVE_ASYNC_INTERRUPT;
1375		1446
1376	sub _have_async_interrupt() {	1447	sub _have_async_interrupt() {
1377	$HAVE_ASYNC_INTERRUPT = 1*(!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT}	1448	$HAVE_ASYNC_INTERRUPT = 1*(!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT}
1378	&& eval "use Async::Interrupt 1.0 (); 1")	1449	&& eval "use Async::Interrupt 1.02 (); 1")
1379	unless defined $HAVE_ASYNC_INTERRUPT;	1450	unless defined $HAVE_ASYNC_INTERRUPT;
1380		1451
1381	$HAVE_ASYNC_INTERRUPT	1452	$HAVE_ASYNC_INTERRUPT
1382	}	1453	}
1383		1454
1384	our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);	1455	our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);
1385	our (%SIG_ASY, %SIG_ASY_W);	1456	our (%SIG_ASY, %SIG_ASY_W);
1386	our ($SIG_COUNT, $SIG_TW);	1457	our ($SIG_COUNT, $SIG_TW);
1387		1458
1388	sub _signal_exec {
1389	$HAVE_ASYNC_INTERRUPT
1390	? $SIGPIPE_R->drain
1391	: sysread $SIGPIPE_R, my $dummy, 9;
1392
1393	while (%SIG_EV) {
1394	for (keys %SIG_EV) {
1395	delete $SIG_EV{$_};
1396	$_->() for values %{ $SIG_CB{$_} || {} };
1397	}
1398	}
1399	}
1400
1401	# install a dummy wakeup watcher to reduce signal catching latency	1459	# install a dummy wakeup watcher to reduce signal catching latency
		1460	# used by Impls
1402	sub _sig_add() {	1461	sub _sig_add() {
1403	unless ($SIG_COUNT++) {	1462	unless ($SIG_COUNT++) {
1404	# try to align timer on a full-second boundary, if possible	1463	# try to align timer on a full-second boundary, if possible
1405	my $NOW = AE::now;	1464	my $NOW = AE::now;
1406		1465
…		…
1416	undef $SIG_TW	1475	undef $SIG_TW
1417	unless --$SIG_COUNT;	1476	unless --$SIG_COUNT;
1418	}	1477	}
1419		1478
1420	our $_sig_name_init; $_sig_name_init = sub {	1479	our $_sig_name_init; $_sig_name_init = sub {
1421	eval q{ # poor man's autoloading	1480	eval q{ # poor man's autoloading {}
1422	undef $_sig_name_init;	1481	undef $_sig_name_init;
1423		1482
1424	if (_have_async_interrupt) {	1483	if (_have_async_interrupt) {
1425	*sig2num = \&Async::Interrupt::sig2num;	1484	*sig2num = \&Async::Interrupt::sig2num;
1426	*sig2name = \&Async::Interrupt::sig2name;	1485	*sig2name = \&Async::Interrupt::sig2name;
…		…
1458	$SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;	1517	$SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;
1459		1518
1460	} else {	1519	} else {
1461	warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;	1520	warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;
1462		1521
1463	require Fcntl;
1464
1465	if (AnyEvent::WIN32) {	1522	if (AnyEvent::WIN32) {
1466	require AnyEvent::Util;	1523	require AnyEvent::Util;
1467		1524
1468	($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();	1525	($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
1469	AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R;	1526	AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R;
1470	AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case	1527	AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case
1471	} else {	1528	} else {
1472	pipe $SIGPIPE_R, $SIGPIPE_W;	1529	pipe $SIGPIPE_R, $SIGPIPE_W;
1473	fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R;	1530	fcntl $SIGPIPE_R, AnyEvent::F_SETFL, AnyEvent::O_NONBLOCK if $SIGPIPE_R;
1474	fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case	1531	fcntl $SIGPIPE_W, AnyEvent::F_SETFL, AnyEvent::O_NONBLOCK if $SIGPIPE_W; # just in case
1475		1532
1476	# not strictly required, as $^F is normally 2, but let's make sure...	1533	# not strictly required, as $^F is normally 2, but let's make sure...
1477	fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;	1534	fcntl $SIGPIPE_R, AnyEvent::F_SETFD, AnyEvent::FD_CLOEXEC;
1478	fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC;	1535	fcntl $SIGPIPE_W, AnyEvent::F_SETFD, AnyEvent::FD_CLOEXEC;
1479	}	1536	}
1480		1537
1481	$SIGPIPE_R	1538	$SIGPIPE_R
1482	or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";	1539	or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1483		1540
1484	$SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec;	1541	$SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec;
1485	}	1542	}
1486		1543
1487	*signal = sub {	1544	*signal = $HAVE_ASYNC_INTERRUPT
		1545	? sub {
1488	my (undef, %arg) = @_;	1546	my (undef, %arg) = @_;
1489		1547
1490	my $signal = uc $arg{signal}
1491	or Carp::croak "required option 'signal' is missing";
1492
1493	if ($HAVE_ASYNC_INTERRUPT) {
1494	# async::interrupt	1548	# async::interrupt
1495
1496	$signal = sig2num $signal;	1549	my $signal = sig2num $arg{signal};
1497	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};	1550	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1498		1551
1499	$SIG_ASY{$signal} ||= new Async::Interrupt	1552	$SIG_ASY{$signal} ||= new Async::Interrupt
1500	cb => sub { undef $SIG_EV{$signal} },	1553	cb => sub { undef $SIG_EV{$signal} },
1501	signal => $signal,	1554	signal => $signal,
1502	pipe => [$SIGPIPE_R->filenos],	1555	pipe => [$SIGPIPE_R->filenos],
1503	pipe_autodrain => 0,	1556	pipe_autodrain => 0,
1504	;	1557	;
1505		1558
1506	} else {	1559	bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
		1560	}
		1561	: sub {
		1562	my (undef, %arg) = @_;
		1563
1507	# pure perl	1564	# pure perl
1508
1509	# AE::Util has been loaded in signal
1510	$signal = sig2name $signal;	1565	my $signal = sig2name $arg{signal};
1511	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};	1566	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1512		1567
1513	$SIG{$signal} ||= sub {	1568	$SIG{$signal} ||= sub {
1514	local $!;	1569	local $!;
1515	syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;	1570	syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
1516	undef $SIG_EV{$signal};	1571	undef $SIG_EV{$signal};
1517	};	1572	};
1518		1573
1519	# can't do signal processing without introducing races in pure perl,	1574	# can't do signal processing without introducing races in pure perl,
1520	# so limit the signal latency.	1575	# so limit the signal latency.
1521	_sig_add;	1576	_sig_add;
1522	}
1523		1577
1524	bless [$signal, $arg{cb}], "AnyEvent::Base::signal"	1578	bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
		1579	}
1525	};	1580	;
1526		1581
1527	*AnyEvent::Base::signal::DESTROY = sub {	1582	*AnyEvent::Base::signal::DESTROY = sub {
1528	my ($signal, $cb) = @{$_[0]};	1583	my ($signal, $cb) = @{$_[0]};
1529		1584
1530	_sig_del;	1585	_sig_del;
…		…
1537	# print weird messages, or just unconditionally exit	1592	# print weird messages, or just unconditionally exit
1538	# instead of getting the default action.	1593	# instead of getting the default action.
1539	undef $SIG{$signal}	1594	undef $SIG{$signal}
1540	unless keys %{ $SIG_CB{$signal} };	1595	unless keys %{ $SIG_CB{$signal} };
1541	};	1596	};
		1597
		1598	*_signal_exec = sub {
		1599	$HAVE_ASYNC_INTERRUPT
		1600	? $SIGPIPE_R->drain
		1601	: sysread $SIGPIPE_R, (my $dummy), 9;
		1602
		1603	while (%SIG_EV) {
		1604	for (keys %SIG_EV) {
		1605	delete $SIG_EV{$_};
		1606	$_->() for values %{ $SIG_CB{$_} || {} };
		1607	}
		1608	}
		1609	};
1542	};	1610	};
1543	die if $@;	1611	die if $@;
		1612
1544	&signal	1613	&signal
1545	}	1614	}
1546		1615
1547	# default implementation for ->child	1616	# default implementation for ->child
1548		1617
1549	our %PID_CB;	1618	our %PID_CB;
1550	our $CHLD_W;	1619	our $CHLD_W;
1551	our $CHLD_DELAY_W;	1620	our $CHLD_DELAY_W;
1552	our $WNOHANG;
1553		1621
		1622	# used by many Impl's
1554	sub _emit_childstatus($$) {	1623	sub _emit_childstatus($$) {
1555	my (undef, $rpid, $rstatus) = @_;	1624	my (undef, $rpid, $rstatus) = @_;
1556		1625
1557	$_->($rpid, $rstatus)	1626	$_->($rpid, $rstatus)
1558	for values %{ $PID_CB{$rpid} || {} },	1627	for values %{ $PID_CB{$rpid} || {} },
1559	values %{ $PID_CB{0} || {} };	1628	values %{ $PID_CB{0} || {} };
1560	}	1629	}
1561		1630
1562	sub _sigchld {
1563	my $pid;
1564
1565	AnyEvent->_emit_childstatus ($pid, $?)
1566	while ($pid = waitpid -1, $WNOHANG) > 0;
1567	}
1568
1569	sub child {	1631	sub child {
		1632	eval q{ # poor man's autoloading {}
		1633	*_sigchld = sub {
		1634	my $pid;
		1635
		1636	AnyEvent->_emit_childstatus ($pid, $?)
		1637	while ($pid = waitpid -1, WNOHANG) > 0;
		1638	};
		1639
		1640	*child = sub {
1570	my (undef, %arg) = @_;	1641	my (undef, %arg) = @_;
1571		1642
1572	defined (my $pid = $arg{pid} + 0)	1643	defined (my $pid = $arg{pid} + 0)
1573	or Carp::croak "required option 'pid' is missing";	1644	or Carp::croak "required option 'pid' is missing";
1574		1645
1575	$PID_CB{$pid}{$arg{cb}} = $arg{cb};	1646	$PID_CB{$pid}{$arg{cb}} = $arg{cb};
1576		1647
1577	# WNOHANG is almost cetrainly 1 everywhere
1578	$WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/
1579	? 1
1580	: eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1;
1581
1582	unless ($CHLD_W) {	1648	unless ($CHLD_W) {
1583	$CHLD_W = AE::signal CHLD => \&_sigchld;	1649	$CHLD_W = AE::signal CHLD => \&_sigchld;
1584	# child could be a zombie already, so make at least one round	1650	# child could be a zombie already, so make at least one round
1585	&_sigchld;	1651	&_sigchld;
1586	}	1652	}
1587		1653
1588	bless [$pid, $arg{cb}], "AnyEvent::Base::child"	1654	bless [$pid, $arg{cb}], "AnyEvent::Base::child"
1589	}	1655	};
1590		1656
1591	sub AnyEvent::Base::child::DESTROY {	1657	*AnyEvent::Base::child::DESTROY = sub {
1592	my ($pid, $cb) = @{$_[0]};	1658	my ($pid, $cb) = @{$_[0]};
1593		1659
1594	delete $PID_CB{$pid}{$cb};	1660	delete $PID_CB{$pid}{$cb};
1595	delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };	1661	delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };
1596		1662
1597	undef $CHLD_W unless keys %PID_CB;	1663	undef $CHLD_W unless keys %PID_CB;
		1664	};
		1665	};
		1666	die if $@;
		1667
		1668	&child
1598	}	1669	}
1599		1670
1600	# idle emulation is done by simply using a timer, regardless	1671	# idle emulation is done by simply using a timer, regardless
1601	# of whether the process is idle or not, and not letting	1672	# of whether the process is idle or not, and not letting
1602	# the callback use more than 50% of the time.	1673	# the callback use more than 50% of the time.
1603	sub idle {	1674	sub idle {
		1675	eval q{ # poor man's autoloading {}
		1676	*idle = sub {
1604	my (undef, %arg) = @_;	1677	my (undef, %arg) = @_;
1605		1678
1606	my ($cb, $w, $rcb) = $arg{cb};	1679	my ($cb, $w, $rcb) = $arg{cb};
1607		1680
1608	$rcb = sub {	1681	$rcb = sub {
1609	if ($cb) {	1682	if ($cb) {
1610	$w = _time;	1683	$w = _time;
1611	&$cb;	1684	&$cb;
1612	$w = _time - $w;	1685	$w = _time - $w;
1613		1686
1614	# never use more then 50% of the time for the idle watcher,	1687	# never use more then 50% of the time for the idle watcher,
1615	# within some limits	1688	# within some limits
1616	$w = 0.0001 if $w < 0.0001;	1689	$w = 0.0001 if $w < 0.0001;
1617	$w = 5 if $w > 5;	1690	$w = 5 if $w > 5;
1618		1691
1619	$w = AE::timer $w, 0, $rcb;	1692	$w = AE::timer $w, 0, $rcb;
1620	} else {	1693	} else {
1621	# clean up...	1694	# clean up...
1622	undef $w;	1695	undef $w;
1623	undef $rcb;	1696	undef $rcb;
		1697	}
		1698	};
		1699
		1700	$w = AE::timer 0.05, 0, $rcb;
		1701
		1702	bless \\$cb, "AnyEvent::Base::idle"
1624	}	1703	};
		1704
		1705	*AnyEvent::Base::idle::DESTROY = sub {
		1706	undef $${$_[0]};
		1707	};
1625	};	1708	};
		1709	die if $@;
1626		1710
1627	$w = AE::timer 0.05, 0, $rcb;	1711	&idle
1628
1629	bless \\$cb, "AnyEvent::Base::idle"
1630	}
1631
1632	sub AnyEvent::Base::idle::DESTROY {
1633	undef $${$_[0]};
1634	}	1712	}
1635		1713
1636	package AnyEvent::CondVar;	1714	package AnyEvent::CondVar;
1637		1715
1638	our @ISA = AnyEvent::CondVar::Base::;	1716	our @ISA = AnyEvent::CondVar::Base::;
		1717
		1718	# only to be used for subclassing
		1719	sub new {
		1720	my $class = shift;
		1721	bless AnyEvent->condvar (@_), $class
		1722	}
1639		1723
1640	package AnyEvent::CondVar::Base;	1724	package AnyEvent::CondVar::Base;
1641		1725
1642	#use overload	1726	#use overload
1643	# '&{}' => sub { my $self = shift; sub { $self->send (@_) } },	1727	# '&{}' => sub { my $self = shift; sub { $self->send (@_) } },
…		…
1765	check the arguments passed to most method calls. If it finds any problems,	1849	check the arguments passed to most method calls. If it finds any problems,
1766	it will croak.	1850	it will croak.
1767		1851
1768	In other words, enables "strict" mode.	1852	In other words, enables "strict" mode.
1769		1853
1770	Unlike C<use strict> (or it's modern cousin, C<< use L<common::sense>	1854	Unlike C<use strict> (or its modern cousin, C<< use L<common::sense>
1771	>>, it is definitely recommended to keep it off in production. Keeping	1855	>>, it is definitely recommended to keep it off in production. Keeping
1772	C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs	1856	C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs
1773	can be very useful, however.	1857	can be very useful, however.
1774		1858
1775	=item C<PERL_ANYEVENT_MODEL>	1859	=item C<PERL_ANYEVENT_MODEL>
…		…
1912	warn "read: $input\n"; # output what has been read	1996	warn "read: $input\n"; # output what has been read
1913	$cv->send if $input =~ /^q/i; # quit program if /^q/i	1997	$cv->send if $input =~ /^q/i; # quit program if /^q/i
1914	},	1998	},
1915	);	1999	);
1916		2000
1917	my $time_watcher; # can only be used once
1918
1919	sub new_timer {
1920	$timer = AnyEvent->timer (after => 1, cb => sub {	2001	my $time_watcher = AnyEvent->timer (after => 1, interval => 1, cb => sub {
1921	warn "timeout\n"; # print 'timeout' about every second	2002	warn "timeout\n"; # print 'timeout' at most every second
1922	&new_timer; # and restart the time
1923	});	2003	});
1924	}
1925
1926	new_timer; # create first timer
1927		2004
1928	$cv->recv; # wait until user enters /^q/i	2005	$cv->recv; # wait until user enters /^q/i
1929		2006
1930	=head1 REAL-WORLD EXAMPLE	2007	=head1 REAL-WORLD EXAMPLE
1931		2008
…		…
2004		2081
2005	The actual code goes further and collects all errors (C<die>s, exceptions)	2082	The actual code goes further and collects all errors (C<die>s, exceptions)
2006	that occurred during request processing. The C<result> method detects	2083	that occurred during request processing. The C<result> method detects
2007	whether an exception as thrown (it is stored inside the $txn object)	2084	whether an exception as thrown (it is stored inside the $txn object)
2008	and just throws the exception, which means connection errors and other	2085	and just throws the exception, which means connection errors and other
2009	problems get reported tot he code that tries to use the result, not in a	2086	problems get reported to the code that tries to use the result, not in a
2010	random callback.	2087	random callback.
2011		2088
2012	All of this enables the following usage styles:	2089	All of this enables the following usage styles:
2013		2090
2014	1. Blocking:	2091	1. Blocking:
…		…
2375	As you can see, the AnyEvent + EV combination even beats the	2452	As you can see, the AnyEvent + EV combination even beats the
2376	hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl	2453	hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl
2377	backend easily beats IO::Lambda and POE.	2454	backend easily beats IO::Lambda and POE.
2378		2455
2379	And even the 100% non-blocking version written using the high-level (and	2456	And even the 100% non-blocking version written using the high-level (and
2380	slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda by a	2457	slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda
2381	large margin, even though it does all of DNS, tcp-connect and socket I/O	2458	higher level ("unoptimised") abstractions by a large margin, even though
2382	in a non-blocking way.	2459	it does all of DNS, tcp-connect and socket I/O in a non-blocking way.
2383		2460
2384	The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and	2461	The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and
2385	F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are	2462	F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are
2386	part of the IO::lambda distribution and were used without any changes.	2463	part of the IO::Lambda distribution and were used without any changes.
2387		2464
2388		2465
2389	=head1 SIGNALS	2466	=head1 SIGNALS
2390		2467
2391	AnyEvent currently installs handlers for these signals:	2468	AnyEvent currently installs handlers for these signals:
…		…
2428	unless defined $SIG{PIPE};	2505	unless defined $SIG{PIPE};
2429		2506
2430	=head1 RECOMMENDED/OPTIONAL MODULES	2507	=head1 RECOMMENDED/OPTIONAL MODULES
2431		2508
2432	One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and	2509	One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and
2433	it's built-in modules) are required to use it.	2510	its built-in modules) are required to use it.
2434		2511
2435	That does not mean that AnyEvent won't take advantage of some additional	2512	That does not mean that AnyEvent won't take advantage of some additional
2436	modules if they are installed.	2513	modules if they are installed.
2437		2514
2438	This section epxlains which additional modules will be used, and how they	2515	This section explains which additional modules will be used, and how they
2439	affect AnyEvent's operetion.	2516	affect AnyEvent's operation.
2440		2517
2441	=over 4	2518	=over 4
2442		2519
2443	=item L<Async::Interrupt>	2520	=item L<Async::Interrupt>
2444		2521
…		…
2449	catch the signals) with some delay (default is 10 seconds, look for	2526	catch the signals) with some delay (default is 10 seconds, look for
2450	C<$AnyEvent::MAX_SIGNAL_LATENCY>).	2527	C<$AnyEvent::MAX_SIGNAL_LATENCY>).
2451		2528
2452	If this module is available, then it will be used to implement signal	2529	If this module is available, then it will be used to implement signal
2453	catching, which means that signals will not be delayed, and the event loop	2530	catching, which means that signals will not be delayed, and the event loop
2454	will not be interrupted regularly, which is more efficient (And good for	2531	will not be interrupted regularly, which is more efficient (and good for
2455	battery life on laptops).	2532	battery life on laptops).
2456		2533
2457	This affects not just the pure-perl event loop, but also other event loops	2534	This affects not just the pure-perl event loop, but also other event loops
2458	that have no signal handling on their own (e.g. Glib, Tk, Qt).	2535	that have no signal handling on their own (e.g. Glib, Tk, Qt).
2459		2536
…		…
2471	automatic timer adjustments even when no monotonic clock is available,	2548	automatic timer adjustments even when no monotonic clock is available,
2472	can take avdantage of advanced kernel interfaces such as C<epoll> and	2549	can take avdantage of advanced kernel interfaces such as C<epoll> and
2473	C<kqueue>, and is the fastest backend I<by far>. You can even embed	2550	C<kqueue>, and is the fastest backend I<by far>. You can even embed
2474	L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>).	2551	L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>).
2475		2552
		2553	If you only use backends that rely on another event loop (e.g. C<Tk>),
		2554	then this module will do nothing for you.
		2555
2476	=item L<Guard>	2556	=item L<Guard>
2477		2557
2478	The guard module, when used, will be used to implement	2558	The guard module, when used, will be used to implement
2479	C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a	2559	C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a
2480	lot less memory), but otherwise doesn't affect guard operation much. It is	2560	lot less memory), but otherwise doesn't affect guard operation much. It is
2481	purely used for performance.	2561	purely used for performance.
2482		2562
2483	=item L<JSON> and L<JSON::XS>	2563	=item L<JSON> and L<JSON::XS>
2484		2564
2485	This module is required when you want to read or write JSON data via	2565	One of these modules is required when you want to read or write JSON data
2486	L<AnyEvent::Handle>. It is also written in pure-perl, but can take	2566	via L<AnyEvent::Handle>. L<JSON> is also written in pure-perl, but can take
2487	advantage of the ultra-high-speed L<JSON::XS> module when it is installed.	2567	advantage of the ultra-high-speed L<JSON::XS> module when it is installed.
2488
2489	In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is
2490	installed.
2491		2568
2492	=item L<Net::SSLeay>	2569	=item L<Net::SSLeay>
2493		2570
2494	Implementing TLS/SSL in Perl is certainly interesting, but not very	2571	Implementing TLS/SSL in Perl is certainly interesting, but not very
2495	worthwhile: If this module is installed, then L<AnyEvent::Handle> (with	2572	worthwhile: If this module is installed, then L<AnyEvent::Handle> (with
2496	the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL.	2573	the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL.
2497		2574
2498	=item L<Time::HiRes>	2575	=item L<Time::HiRes>
2499		2576
2500	This module is part of perl since release 5.008. It will be used when the	2577	This module is part of perl since release 5.008. It will be used when the
2501	chosen event library does not come with a timing source on it's own. The	2578	chosen event library does not come with a timing source of its own. The
2502	pure-perl event loop (L<AnyEvent::Impl::Perl>) will additionally use it to	2579	pure-perl event loop (L<AnyEvent::Impl::Perl>) will additionally use it to
2503	try to use a monotonic clock for timing stability.	2580	try to use a monotonic clock for timing stability.
2504		2581
2505	=back	2582	=back
2506		2583
2507		2584
2508	=head1 FORK	2585	=head1 FORK
2509		2586
2510	Most event libraries are not fork-safe. The ones who are usually are	2587	Most event libraries are not fork-safe. The ones who are usually are
2511	because they rely on inefficient but fork-safe C<select> or C<poll>	2588	because they rely on inefficient but fork-safe C<select> or C<poll> calls
2512	calls. Only L<EV> is fully fork-aware.	2589	- higher performance APIs such as BSD's kqueue or the dreaded Linux epoll
		2590	are usually badly thought-out hacks that are incompatible with fork in
		2591	one way or another. Only L<EV> is fully fork-aware and ensures that you
		2592	continue event-processing in both parent and child (or both, if you know
		2593	what you are doing).
		2594
		2595	This means that, in general, you cannot fork and do event processing in
		2596	the child if the event library was initialised before the fork (which
		2597	usually happens when the first AnyEvent watcher is created, or the library
		2598	is loaded).
2513		2599
2514	If you have to fork, you must either do so I<before> creating your first	2600	If you have to fork, you must either do so I<before> creating your first
2515	watcher OR you must not use AnyEvent at all in the child OR you must do	2601	watcher OR you must not use AnyEvent at all in the child OR you must do
2516	something completely out of the scope of AnyEvent.	2602	something completely out of the scope of AnyEvent.
		2603
		2604	The problem of doing event processing in the parent I<and> the child
		2605	is much more complicated: even for backends that I<are> fork-aware or
		2606	fork-safe, their behaviour is not usually what you want: fork clones all
		2607	watchers, that means all timers, I/O watchers etc. are active in both
		2608	parent and child, which is almost never what you want. USing C<exec>
		2609	to start worker children from some kind of manage rprocess is usually
		2610	preferred, because it is much easier and cleaner, at the expense of having
		2611	to have another binary.
2517		2612
2518		2613
2519	=head1 SECURITY CONSIDERATIONS	2614	=head1 SECURITY CONSIDERATIONS
2520		2615
2521	AnyEvent can be forced to load any event model via	2616	AnyEvent can be forced to load any event model via
…		…
2551	pronounced).	2646	pronounced).
2552		2647
2553		2648
2554	=head1 SEE ALSO	2649	=head1 SEE ALSO
2555		2650
		2651	Tutorial/Introduction: L<AnyEvent::Intro>.
		2652
		2653	FAQ: L<AnyEvent::FAQ>.
		2654
2556	Utility functions: L<AnyEvent::Util>.	2655	Utility functions: L<AnyEvent::Util>.
2557		2656
2558	Event modules: L<EV>, L<EV::Glib>, L<Glib::EV>, L<Event>, L<Glib::Event>,	2657	Event modules: L<EV>, L<EV::Glib>, L<Glib::EV>, L<Event>, L<Glib::Event>,
2559	L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.	2658	L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.
2560		2659
…		…
2566	Non-blocking file handles, sockets, TCP clients and	2665	Non-blocking file handles, sockets, TCP clients and
2567	servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.	2666	servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.
2568		2667
2569	Asynchronous DNS: L<AnyEvent::DNS>.	2668	Asynchronous DNS: L<AnyEvent::DNS>.
2570		2669
2571	Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>,	2670	Thread support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>.
2572	L<Coro::Event>,
2573		2671
2574	Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::XMPP>,	2672	Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::IRC>,
2575	L<AnyEvent::HTTP>.	2673	L<AnyEvent::HTTP>.
2576		2674
2577		2675
2578	=head1 AUTHOR	2676	=head1 AUTHOR
2579		2677

Diff Legend

–	Removed lines
+	Added lines
<	Changed lines
>	Changed lines