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Revision 1.320 by root, Mon Apr 12 02:50:31 2010 UTC vs.
Revision 1.414 by root, Wed Aug 21 08:40:28 2013 UTC

1	=head1 NAME	1	=head1 NAME
2		2
3	AnyEvent - the DBI of event loop programming	3	AnyEvent - the DBI of event loop programming
4		4
5	EV, Event, Glib, Tk, Perl, Event::Lib, Irssi, rxvt-unicode, IO::Async, Qt	5	EV, Event, Glib, Tk, Perl, Event::Lib, Irssi, rxvt-unicode, IO::Async, Qt,
6	and POE are various supported event loops/environments.	6	FLTK and POE are various supported event loops/environments.
7		7
8	=head1 SYNOPSIS	8	=head1 SYNOPSIS
9		9
10	use AnyEvent;	10	use AnyEvent;
11		11
12	# if you prefer function calls, look at the L<AE> manpage for	12	# if you prefer function calls, look at the AE manpage for
13	# an alternative API.	13	# an alternative API.
14		14
15	# file handle or descriptor readable	15	# file handle or descriptor readable
16	my $w = AnyEvent->io (fh => $fh, poll => "r", cb => sub { ... });	16	my $w = AnyEvent->io (fh => $fh, poll => "r", cb => sub { ... });
17		17
18	# one-shot or repeating timers	18	# one-shot or repeating timers
19	my $w = AnyEvent->timer (after => $seconds, cb => sub { ... });	19	my $w = AnyEvent->timer (after => $seconds, cb => sub { ... });
20	my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ...	20	my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ...);
21		21
22	print AnyEvent->now; # prints current event loop time	22	print AnyEvent->now; # prints current event loop time
23	print AnyEvent->time; # think Time::HiRes::time or simply CORE::time.	23	print AnyEvent->time; # think Time::HiRes::time or simply CORE::time.
24		24
25	# POSIX signal	25	# POSIX signal
…		…
46	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
47	L<AnyEvent::Intro> manpage.	47	L<AnyEvent::Intro> manpage.
48		48
49	=head1 SUPPORT	49	=head1 SUPPORT
50		50
		51	An FAQ document is available as L<AnyEvent::FAQ>.
		52
51	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
52	channel, too.	54	channel, too.
53		55
54	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
55	Repository>, at L<http://anyevent.schmorp.de>, for more info.	57	Repository>, at L<http://anyevent.schmorp.de>, for more info.
56		58
…		…
76	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
77	model you use.	79	model you use.
78		80
79	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
80	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
81	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
82	cannot use anything else, as they are simply incompatible to everything	84	cannot use anything else, as they are simply incompatible to everything
83	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
84	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.
85		87
86	AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works	88	AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works
87	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
88	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
89	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
90	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
91	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
92	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,
93	to AnyEvent, too, so it is future-proof).	95	so it is future-proof).
94		96
95	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
96	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
97	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
98	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
99	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
100	technically possible.	102	technically possible.
101		103
102	Of course, AnyEvent comes with a big (and fully optional!) toolbox	104	Of course, AnyEvent comes with a big (and fully optional!) toolbox
103	of useful functionality, such as an asynchronous DNS resolver, 100%	105	of useful functionality, such as an asynchronous DNS resolver, 100%
…		…
109	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
110	model, you should I<not> use this module.	112	model, you should I<not> use this module.
111		113
112	=head1 DESCRIPTION	114	=head1 DESCRIPTION
113		115
114	L<AnyEvent> provides an identical interface to multiple event loops. This	116	L<AnyEvent> provides a uniform interface to various event loops. This
115	allows module authors to utilise an event loop without forcing module	117	allows module authors to use event loop functionality without forcing
116	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
117	peacefully at any one time).	119	than one event loop cannot coexist peacefully).
118		120
119	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>
120	module.	122	module.
121		123
122	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
123	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
124	following modules is already loaded: L<EV>,	126	following modules is already loaded: L<EV>, L<AnyEvent::Loop>,
125	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
126	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
127	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
128	adaptor should always succeed) in the order given. The first one that can	130	available, the pure-perl L<AnyEvent::Loop> should always work, so
129	be successfully loaded will be used. If, after this, still none could be	131	the other two are not normally tried.
130	found, AnyEvent will fall back to a pure-perl event loop, which is not
131	very efficient, but should work everywhere.
132		132
133	Because AnyEvent first checks for modules that are already loaded, loading	133	Because AnyEvent first checks for modules that are already loaded, loading
134	an event model explicitly before first using AnyEvent will likely make	134	an event model explicitly before first using AnyEvent will likely make
135	that model the default. For example:	135	that model the default. For example:
136		136
…		…
138	use AnyEvent;	138	use AnyEvent;
139		139
140	# .. AnyEvent will likely default to Tk	140	# .. AnyEvent will likely default to Tk
141		141
142	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
143	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,
144	use AnyEvent so their modules work together with others seamlessly...	144	as very few modules hardcode event loops without announcing this very
		145	loudly.
145		146
146	The pure-perl implementation of AnyEvent is called	147	The pure-perl implementation of AnyEvent is called C<AnyEvent::Loop>. Like
147	C<AnyEvent::Impl::Perl>. Like other event modules you can load it	148	other event modules you can load it explicitly and enjoy the high
148	explicitly and enjoy the high availability of that event loop :)	149	availability of that event loop :)
149		150
150	=head1 WATCHERS	151	=head1 WATCHERS
151		152
152	AnyEvent has the central concept of a I<watcher>, which is an object that	153	AnyEvent has the central concept of a I<watcher>, which is an object that
153	stores relevant data for each kind of event you are waiting for, such as	154	stores relevant data for each kind of event you are waiting for, such as
…		…
158	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
159	is in control).	160	is in control).
160		161
161	Note that B<callbacks must not permanently change global variables>	162	Note that B<callbacks must not permanently change global variables>
162	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<<
163	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
164	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
165	widely between event loops.	166	widely between event loops.
166		167
167	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
168	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
169	to it).	170	to it).
170		171
171	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.
172		173
173	Many watchers either are used with "recursion" (repeating timers for	174	Many watchers either are used with "recursion" (repeating timers for
174	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.
175		176
176	An any way to achieve that is this pattern:	177	One way to achieve that is this pattern:
177		178
178	my $w; $w = AnyEvent->type (arg => value ..., cb => sub {	179	my $w; $w = AnyEvent->type (arg => value ..., cb => sub {
179	# you can use $w here, for example to undef it	180	# you can use $w here, for example to undef it
180	undef $w;	181	undef $w;
181	});	182	});
…		…
213		214
214	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.
215	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
216	underlying file descriptor.	217	underlying file descriptor.
217		218
218	Some event loops issue spurious readyness notifications, so you should	219	Some event loops issue spurious readiness notifications, so you should
219	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
220	handles.	221	handles.
221		222
222	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
223	watcher.	224	watcher.
…		…
247		248
248	Although the callback might get passed parameters, their value and	249	Although the callback might get passed parameters, their value and
249	presence is undefined and you cannot rely on them. Portable AnyEvent	250	presence is undefined and you cannot rely on them. Portable AnyEvent
250	callbacks cannot use arguments passed to time watcher callbacks.	251	callbacks cannot use arguments passed to time watcher callbacks.
251		252
252	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
253	parameter, C<interval>, as a strictly positive number (> 0), then the	254	parameter, C<interval>, as a strictly positive number (> 0), then the
254	callback will be invoked regularly at that interval (in fractional	255	callback will be invoked regularly at that interval (in fractional
255	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
256	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.
257		258
258	The callback will be rescheduled before invoking the callback, but no	259	The callback will be rescheduled before invoking the callback, but no
259	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
260	only approximate.	261	only approximate.
261		262
262	Example: fire an event after 7.7 seconds.	263	Example: fire an event after 7.7 seconds.
263		264
264	my $w = AnyEvent->timer (after => 7.7, cb => sub {	265	my $w = AnyEvent->timer (after => 7.7, cb => sub {
…		…
270		271
271	Example 2: fire an event after 0.5 seconds, then roughly every second.	272	Example 2: fire an event after 0.5 seconds, then roughly every second.
272		273
273	my $w = AnyEvent->timer (after => 0.5, interval => 1, cb => sub {	274	my $w = AnyEvent->timer (after => 0.5, interval => 1, cb => sub {
274	warn "timeout\n";	275	warn "timeout\n";
275	};	276	});
276		277
277	=head3 TIMING ISSUES	278	=head3 TIMING ISSUES
278		279
279	There are two ways to handle timers: based on real time (relative, "fire	280	There are two ways to handle timers: based on real time (relative, "fire
280	in 10 seconds") and based on wallclock time (absolute, "fire at 12	281	in 10 seconds") and based on wallclock time (absolute, "fire at 12
…		…
282		283
283	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
284	use absolute time internally. This makes a difference when your clock	285	use absolute time internally. This makes a difference when your clock
285	"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
286	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
287	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.
288		289
289	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
290	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
291	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)
292	timers.	293	timers.
293		294
294	AnyEvent always prefers relative timers, if available, matching the	295	AnyEvent always prefers relative timers, if available, matching the
295	AnyEvent API.	296	AnyEvent API.
…		…
317	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
318	function to call when you want to know the current time.>	319	function to call when you want to know the current time.>
319		320
320	This function is also often faster then C<< AnyEvent->time >>, and	321	This function is also often faster then C<< AnyEvent->time >>, and
321	thus the preferred method if you want some timestamp (for example,	322	thus the preferred method if you want some timestamp (for example,
322	L<AnyEvent::Handle> uses this to update it's activity timeouts).	323	L<AnyEvent::Handle> uses this to update its activity timeouts).
323		324
324	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
325	with your timing, you can skip it without bad conscience.	326	with your timing; you can skip it without a bad conscience.
326		327
327	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>
328	and L<EV> and the following set-up:	329	and L<EV> and the following set-up:
329		330
330	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
331	time=500 (assume no other callbacks delay processing). In your callback,	332	time=500 (assume no other callbacks delay processing). In your callback,
332	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
333	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
334	after three seconds.	335	after three seconds.
335		336
…		…
355	difference between C<< AnyEvent->time >> and C<< AnyEvent->now >> into	356	difference between C<< AnyEvent->time >> and C<< AnyEvent->now >> into
356	account.	357	account.
357		358
358	=item AnyEvent->now_update	359	=item AnyEvent->now_update
359		360
360	Some event loops (such as L<EV> or L<AnyEvent::Impl::Perl>) cache	361	Some event loops (such as L<EV> or L<AnyEvent::Loop>) cache the current
361	the current time for each loop iteration (see the discussion of L<<	362	time for each loop iteration (see the discussion of L<< AnyEvent->now >>,
362	AnyEvent->now >>, above).	363	above).
363		364
364	When a callback runs for a long time (or when the process sleeps), then	365	When a callback runs for a long time (or when the process sleeps), then
365	this "current" time will differ substantially from the real time, which	366	this "current" time will differ substantially from the real time, which
366	might affect timers and time-outs.	367	might affect timers and time-outs.
367		368
…		…
414	not restart syscalls (that includes L<Async::Interrupt> and AnyEvent's	415	not restart syscalls (that includes L<Async::Interrupt> and AnyEvent's
415	pure perl implementation).	416	pure perl implementation).
416		417
417	=head3 Safe/Unsafe Signals	418	=head3 Safe/Unsafe Signals
418		419
419	Perl signals can be either "safe" (synchronous to opcode handling) or	420	Perl signals can be either "safe" (synchronous to opcode handling)
420	"unsafe" (asynchronous) - the former might get delayed indefinitely, the	421	or "unsafe" (asynchronous) - the former might delay signal delivery
421	latter might corrupt your memory.	422	indefinitely, the latter might corrupt your memory.
422		423
423	AnyEvent signal handlers are, in addition, synchronous to the event loop,	424	AnyEvent signal handlers are, in addition, synchronous to the event loop,
424	i.e. they will not interrupt your running perl program but will only be	425	i.e. they will not interrupt your running perl program but will only be
425	called as part of the normal event handling (just like timer, I/O etc.	426	called as part of the normal event handling (just like timer, I/O etc.
426	callbacks, too).	427	callbacks, too).
427		428
428	=head3 Signal Races, Delays and Workarounds	429	=head3 Signal Races, Delays and Workarounds
429		430
430	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
431	callbacks to signals in a generic way, which is a pity, as you cannot	432	attaching callbacks to signals in a generic way, which is a pity,
432	do race-free signal handling in perl, requiring C libraries for	433	as you cannot do race-free signal handling in perl, requiring
433	this. AnyEvent will try to do it's best, which means in some cases,	434	C libraries for this. AnyEvent will try to do its best, which
434	signals will be delayed. The maximum time a signal might be delayed is	435	means in some cases, signals will be delayed. The maximum time
435	specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This	436	a signal might be delayed is 10 seconds by default, but can
436	variable can be changed only before the first signal watcher is created,	437	be overriden via C<$ENV{PERL_ANYEVENT_MAX_SIGNAL_LATENCY}> or
437	and should be left alone otherwise. This variable determines how often	438	C<$AnyEvent::MAX_SIGNAL_LATENCY> - see the L<ENVIRONMENT VARIABLES>
438	AnyEvent polls for signals (in case a wake-up was missed). Higher values	439	section for details.
439	will cause fewer spurious wake-ups, which is better for power and CPU
440	saving.
441		440
442	All these problems can be avoided by installing the optional	441	All these problems can be avoided by installing the optional
443	L<Async::Interrupt> module, which works with most event loops. It will not	442	L<Async::Interrupt> module, which works with most event loops. It will not
444	work with inherently broken event loops such as L<Event> or L<Event::Lib>	443	work with inherently broken event loops such as L<Event> or L<Event::Lib>
445	(and not with L<POE> currently, as POE does it's own workaround with	444	(and not with L<POE> currently). For those, you just have to suffer the
446	one-second latency). For those, you just have to suffer the delays.	445	delays.
447		446
448	=head2 CHILD PROCESS WATCHERS	447	=head2 CHILD PROCESS WATCHERS
449		448
450	$w = AnyEvent->child (pid => <process id>, cb => <callback>);	449	$w = AnyEvent->child (pid => <process id>, cb => <callback>);
451		450
452	You can also watch on a child process exit and catch its exit status.	451	You can also watch for a child process exit and catch its exit status.
453		452
454	The child process is specified by the C<pid> argument (one some backends,	453	The child process is specified by the C<pid> argument (on some backends,
455	using C<0> watches for any child process exit, on others this will	454	using C<0> watches for any child process exit, on others this will
456	croak). The watcher will be triggered only when the child process has	455	croak). The watcher will be triggered only when the child process has
457	finished and an exit status is available, not on any trace events	456	finished and an exit status is available, not on any trace events
458	(stopped/continued).	457	(stopped/continued).
459		458
…		…
481	thing in an AnyEvent program, you I<have> to create at least one	480	thing in an AnyEvent program, you I<have> to create at least one
482	watcher before you C<fork> the child (alternatively, you can call	481	watcher before you C<fork> the child (alternatively, you can call
483	C<AnyEvent::detect>).	482	C<AnyEvent::detect>).
484		483
485	As most event loops do not support waiting for child events, they will be	484	As most event loops do not support waiting for child events, they will be
486	emulated by AnyEvent in most cases, in which the latency and race problems	485	emulated by AnyEvent in most cases, in which case the latency and race
487	mentioned in the description of signal watchers apply.	486	problems mentioned in the description of signal watchers apply.
488		487
489	Example: fork a process and wait for it	488	Example: fork a process and wait for it
490		489
491	my $done = AnyEvent->condvar;	490	my $done = AnyEvent->condvar;
492		491
…		…
506		505
507	=head2 IDLE WATCHERS	506	=head2 IDLE WATCHERS
508		507
509	$w = AnyEvent->idle (cb => <callback>);	508	$w = AnyEvent->idle (cb => <callback>);
510		509
511	Repeatedly invoke the callback after the process becomes idle, until	510	This will repeatedly invoke the callback after the process becomes idle,
512	either the watcher is destroyed or new events have been detected.	511	until either the watcher is destroyed or new events have been detected.
513		512
514	Idle watchers are useful when there is a need to do something, but it	513	Idle watchers are useful when there is a need to do something, but it
515	is not so important (or wise) to do it instantly. The callback will be	514	is not so important (or wise) to do it instantly. The callback will be
516	invoked only when there is "nothing better to do", which is usually	515	invoked only when there is "nothing better to do", which is usually
517	defined as "all outstanding events have been handled and no new events	516	defined as "all outstanding events have been handled and no new events
…		…
556	will actively watch for new events and call your callbacks.	555	will actively watch for new events and call your callbacks.
557		556
558	AnyEvent is slightly different: it expects somebody else to run the event	557	AnyEvent is slightly different: it expects somebody else to run the event
559	loop and will only block when necessary (usually when told by the user).	558	loop and will only block when necessary (usually when told by the user).
560		559
561	The instrument to do that is called a "condition variable", so called	560	The tool to do that is called a "condition variable", so called because
562	because they represent a condition that must become true.	561	they represent a condition that must become true.
563		562
564	Now is probably a good time to look at the examples further below.	563	Now is probably a good time to look at the examples further below.
565		564
566	Condition variables can be created by calling the C<< AnyEvent->condvar	565	Condition variables can be created by calling the C<< AnyEvent->condvar
567	>> method, usually without arguments. The only argument pair allowed is	566	>> method, usually without arguments. The only argument pair allowed is
…		…
572	After creation, the condition variable is "false" until it becomes "true"	571	After creation, the condition variable is "false" until it becomes "true"
573	by calling the C<send> method (or calling the condition variable as if it	572	by calling the C<send> method (or calling the condition variable as if it
574	were a callback, read about the caveats in the description for the C<<	573	were a callback, read about the caveats in the description for the C<<
575	->send >> method).	574	->send >> method).
576		575
577	Condition variables are similar to callbacks, except that you can	576	Since condition variables are the most complex part of the AnyEvent API, here are
578	optionally wait for them. They can also be called merge points - points	577	some different mental models of what they are - pick the ones you can connect to:
579	in time where multiple outstanding events have been processed. And yet	578
580	another way to call them is transactions - each condition variable can be	579	=over 4
581	used to represent a transaction, which finishes at some point and delivers	580
582	a result. And yet some people know them as "futures" - a promise to	581	=item * Condition variables are like callbacks - you can call them (and pass them instead
583	compute/deliver something that you can wait for.	582	of callbacks). Unlike callbacks however, you can also wait for them to be called.
		583
		584	=item * Condition variables are signals - one side can emit or send them,
		585	the other side can wait for them, or install a handler that is called when
		586	the signal fires.
		587
		588	=item * Condition variables are like "Merge Points" - points in your program
		589	where you merge multiple independent results/control flows into one.
		590
		591	=item * Condition variables represent a transaction - functions that start
		592	some kind of transaction can return them, leaving the caller the choice
		593	between waiting in a blocking fashion, or setting a callback.
		594
		595	=item * Condition variables represent future values, or promises to deliver
		596	some result, long before the result is available.
		597
		598	=back
584		599
585	Condition variables are very useful to signal that something has finished,	600	Condition variables are very useful to signal that something has finished,
586	for example, if you write a module that does asynchronous http requests,	601	for example, if you write a module that does asynchronous http requests,
587	then a condition variable would be the ideal candidate to signal the	602	then a condition variable would be the ideal candidate to signal the
588	availability of results. The user can either act when the callback is	603	availability of results. The user can either act when the callback is
…		…
601		616
602	Condition variables are represented by hash refs in perl, and the keys	617	Condition variables are represented by hash refs in perl, and the keys
603	used by AnyEvent itself are all named C<_ae_XXX> to make subclassing	618	used by AnyEvent itself are all named C<_ae_XXX> to make subclassing
604	easy (it is often useful to build your own transaction class on top of	619	easy (it is often useful to build your own transaction class on top of
605	AnyEvent). To subclass, use C<AnyEvent::CondVar> as base class and call	620	AnyEvent). To subclass, use C<AnyEvent::CondVar> as base class and call
606	it's C<new> method in your own C<new> method.	621	its C<new> method in your own C<new> method.
607		622
608	There are two "sides" to a condition variable - the "producer side" which	623	There are two "sides" to a condition variable - the "producer side" which
609	eventually calls C<< -> send >>, and the "consumer side", which waits	624	eventually calls C<< -> send >>, and the "consumer side", which waits
610	for the send to occur.	625	for the send to occur.
611		626
…		…
676	they were a code reference). Calling them directly is the same as calling	691	they were a code reference). Calling them directly is the same as calling
677	C<send>.	692	C<send>.
678		693
679	=item $cv->croak ($error)	694	=item $cv->croak ($error)
680		695
681	Similar to send, but causes all call's to C<< ->recv >> to invoke	696	Similar to send, but causes all calls to C<< ->recv >> to invoke
682	C<Carp::croak> with the given error message/object/scalar.	697	C<Carp::croak> with the given error message/object/scalar.
683		698
684	This can be used to signal any errors to the condition variable	699	This can be used to signal any errors to the condition variable
685	user/consumer. Doing it this way instead of calling C<croak> directly	700	user/consumer. Doing it this way instead of calling C<croak> directly
686	delays the error detetcion, but has the overwhelmign advantage that it	701	delays the error detection, but has the overwhelming advantage that it
687	diagnoses the error at the place where the result is expected, and not	702	diagnoses the error at the place where the result is expected, and not
688	deep in some event clalback without connection to the actual code causing	703	deep in some event callback with no connection to the actual code causing
689	the problem.	704	the problem.
690		705
691	=item $cv->begin ([group callback])	706	=item $cv->begin ([group callback])
692		707
693	=item $cv->end	708	=item $cv->end
…		…
731	one call to C<begin>, so the condvar waits for all calls to C<end> before	746	one call to C<begin>, so the condvar waits for all calls to C<end> before
732	sending.	747	sending.
733		748
734	The ping example mentioned above is slightly more complicated, as the	749	The ping example mentioned above is slightly more complicated, as the
735	there are results to be passwd back, and the number of tasks that are	750	there are results to be passwd back, and the number of tasks that are
736	begung can potentially be zero:	751	begun can potentially be zero:
737		752
738	my $cv = AnyEvent->condvar;	753	my $cv = AnyEvent->condvar;
739		754
740	my %result;	755	my %result;
741	$cv->begin (sub { shift->send (\%result) });	756	$cv->begin (sub { shift->send (\%result) });
…		…
748	};	763	};
749	}	764	}
750		765
751	$cv->end;	766	$cv->end;
752		767
		768	...
		769
		770	my $results = $cv->recv;
		771
753	This code fragment supposedly pings a number of hosts and calls	772	This code fragment supposedly pings a number of hosts and calls
754	C<send> after results for all then have have been gathered - in any	773	C<send> after results for all then have have been gathered - in any
755	order. To achieve this, the code issues a call to C<begin> when it starts	774	order. To achieve this, the code issues a call to C<begin> when it starts
756	each ping request and calls C<end> when it has received some result for	775	each ping request and calls C<end> when it has received some result for
757	it. Since C<begin> and C<end> only maintain a counter, the order in which	776	it. Since C<begin> and C<end> only maintain a counter, the order in which
…		…
762	to be called once the counter reaches C<0>, and second, it ensures that	781	to be called once the counter reaches C<0>, and second, it ensures that
763	C<send> is called even when C<no> hosts are being pinged (the loop	782	C<send> is called even when C<no> hosts are being pinged (the loop
764	doesn't execute once).	783	doesn't execute once).
765		784
766	This is the general pattern when you "fan out" into multiple (but	785	This is the general pattern when you "fan out" into multiple (but
767	potentially none) subrequests: use an outer C<begin>/C<end> pair to set	786	potentially zero) subrequests: use an outer C<begin>/C<end> pair to set
768	the callback and ensure C<end> is called at least once, and then, for each	787	the callback and ensure C<end> is called at least once, and then, for each
769	subrequest you start, call C<begin> and for each subrequest you finish,	788	subrequest you start, call C<begin> and for each subrequest you finish,
770	call C<end>.	789	call C<end>.
771		790
772	=back	791	=back
…		…
779	=over 4	798	=over 4
780		799
781	=item $cv->recv	800	=item $cv->recv
782		801
783	Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak	802	Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak
784	>> methods have been called on c<$cv>, while servicing other watchers	803	>> methods have been called on C<$cv>, while servicing other watchers
785	normally.	804	normally.
786		805
787	You can only wait once on a condition - additional calls are valid but	806	You can only wait once on a condition - additional calls are valid but
788	will return immediately.	807	will return immediately.
789		808
…		…
792		811
793	In list context, all parameters passed to C<send> will be returned,	812	In list context, all parameters passed to C<send> will be returned,
794	in scalar context only the first one will be returned.	813	in scalar context only the first one will be returned.
795		814
796	Note that doing a blocking wait in a callback is not supported by any	815	Note that doing a blocking wait in a callback is not supported by any
797	event loop, that is, recursive invocation of a blocking C<< ->recv	816	event loop, that is, recursive invocation of a blocking C<< ->recv >> is
798	>> is not allowed, and the C<recv> call will C<croak> if such a	817	not allowed and the C<recv> call will C<croak> if such a condition is
799	condition is detected. This condition can be slightly loosened by using	818	detected. This requirement can be dropped by relying on L<Coro::AnyEvent>
800	L<Coro::AnyEvent>, which allows you to do a blocking C<< ->recv >> from	819	, which allows you to do a blocking C<< ->recv >> from any thread
801	any thread that doesn't run the event loop itself.	820	that doesn't run the event loop itself. L<Coro::AnyEvent> is loaded
		821	automatically when L<Coro> is used with L<AnyEvent>, so code does not need
		822	to do anything special to take advantage of that: any code that would
		823	normally block your program because it calls C<recv>, be executed in an
		824	C<async> thread instead without blocking other threads.
802		825
803	Not all event models support a blocking wait - some die in that case	826	Not all event models support a blocking wait - some die in that case
804	(programs might want to do that to stay interactive), so I<if you are	827	(programs might want to do that to stay interactive), so I<if you are
805	using this from a module, never require a blocking wait>. Instead, let the	828	using this from a module, never require a blocking wait>. Instead, let the
806	caller decide whether the call will block or not (for example, by coupling	829	caller decide whether the call will block or not (for example, by coupling
807	condition variables with some kind of request results and supporting	830	condition variables with some kind of request results and supporting
808	callbacks so the caller knows that getting the result will not block,	831	callbacks so the caller knows that getting the result will not block,
809	while still supporting blocking waits if the caller so desires).	832	while still supporting blocking waits if the caller so desires).
810		833
811	You can ensure that C<< -recv >> never blocks by setting a callback and	834	You can ensure that C<< ->recv >> never blocks by setting a callback and
812	only calling C<< ->recv >> from within that callback (or at a later	835	only calling C<< ->recv >> from within that callback (or at a later
813	time). This will work even when the event loop does not support blocking	836	time). This will work even when the event loop does not support blocking
814	waits otherwise.	837	waits otherwise.
815		838
816	=item $bool = $cv->ready	839	=item $bool = $cv->ready
…		…
821	=item $cb = $cv->cb ($cb->($cv))	844	=item $cb = $cv->cb ($cb->($cv))
822		845
823	This is a mutator function that returns the callback set and optionally	846	This is a mutator function that returns the callback set and optionally
824	replaces it before doing so.	847	replaces it before doing so.
825		848
826	The callback will be called when the condition becomes (or already was)	849	The callback will be called when the condition becomes "true", i.e. when
827	"true", i.e. when C<send> or C<croak> are called (or were called), with	850	C<send> or C<croak> are called, with the only argument being the
828	the only argument being the condition variable itself. Calling C<recv>	851	condition variable itself. If the condition is already true, the
		852	callback is called immediately when it is set. Calling C<recv> inside
829	inside the callback or at any later time is guaranteed not to block.	853	the callback or at any later time is guaranteed not to block.
830		854
831	=back	855	=back
832		856
833	=head1 SUPPORTED EVENT LOOPS/BACKENDS	857	=head1 SUPPORTED EVENT LOOPS/BACKENDS
834		858
…		…
842	use. If EV is not installed, then AnyEvent will fall back to its own	866	use. If EV is not installed, then AnyEvent will fall back to its own
843	pure-perl implementation, which is available everywhere as it comes with	867	pure-perl implementation, which is available everywhere as it comes with
844	AnyEvent itself.	868	AnyEvent itself.
845		869
846	AnyEvent::Impl::EV based on EV (interface to libev, best choice).	870	AnyEvent::Impl::EV based on EV (interface to libev, best choice).
847	AnyEvent::Impl::Perl pure-perl implementation, fast and portable.	871	AnyEvent::Impl::Perl pure-perl AnyEvent::Loop, fast and portable.
848		872
849	=item Backends that are transparently being picked up when they are used.	873	=item Backends that are transparently being picked up when they are used.
850		874
851	These will be used when they are currently loaded when the first watcher	875	These will be used if they are already loaded when the first watcher
852	is created, in which case it is assumed that the application is using	876	is created, in which case it is assumed that the application is using
853	them. This means that AnyEvent will automatically pick the right backend	877	them. This means that AnyEvent will automatically pick the right backend
854	when the main program loads an event module before anything starts to	878	when the main program loads an event module before anything starts to
855	create watchers. Nothing special needs to be done by the main program.	879	create watchers. Nothing special needs to be done by the main program.
856		880
…		…
858	AnyEvent::Impl::Glib based on Glib, slow but very stable.	882	AnyEvent::Impl::Glib based on Glib, slow but very stable.
859	AnyEvent::Impl::Tk based on Tk, very broken.	883	AnyEvent::Impl::Tk based on Tk, very broken.
860	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.	884	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
861	AnyEvent::Impl::POE based on POE, very slow, some limitations.	885	AnyEvent::Impl::POE based on POE, very slow, some limitations.
862	AnyEvent::Impl::Irssi used when running within irssi.	886	AnyEvent::Impl::Irssi used when running within irssi.
		887	AnyEvent::Impl::IOAsync based on IO::Async.
		888	AnyEvent::Impl::Cocoa based on Cocoa::EventLoop.
		889	AnyEvent::Impl::FLTK based on FLTK (fltk 2 binding).
863		890
864	=item Backends with special needs.	891	=item Backends with special needs.
865		892
866	Qt requires the Qt::Application to be instantiated first, but will	893	Qt requires the Qt::Application to be instantiated first, but will
867	otherwise be picked up automatically. As long as the main program	894	otherwise be picked up automatically. As long as the main program
868	instantiates the application before any AnyEvent watchers are created,	895	instantiates the application before any AnyEvent watchers are created,
869	everything should just work.	896	everything should just work.
870		897
871	AnyEvent::Impl::Qt based on Qt.	898	AnyEvent::Impl::Qt based on Qt.
872		899
873	Support for IO::Async can only be partial, as it is too broken and
874	architecturally limited to even support the AnyEvent API. It also
875	is the only event loop that needs the loop to be set explicitly, so
876	it can only be used by a main program knowing about AnyEvent. See
877	L<AnyEvent::Impl::Async> for the gory details.
878
879	AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed.
880
881	=item Event loops that are indirectly supported via other backends.	900	=item Event loops that are indirectly supported via other backends.
882		901
883	Some event loops can be supported via other modules:	902	Some event loops can be supported via other modules:
884		903
885	There is no direct support for WxWidgets (L<Wx>) or L<Prima>.	904	There is no direct support for WxWidgets (L<Wx>) or L<Prima>.
…		…
910	Contains C<undef> until the first watcher is being created, before the	929	Contains C<undef> until the first watcher is being created, before the
911	backend has been autodetected.	930	backend has been autodetected.
912		931
913	Afterwards it contains the event model that is being used, which is the	932	Afterwards it contains the event model that is being used, which is the
914	name of the Perl class implementing the model. This class is usually one	933	name of the Perl class implementing the model. This class is usually one
915	of the C<AnyEvent::Impl:xxx> modules, but can be any other class in the	934	of the C<AnyEvent::Impl::xxx> modules, but can be any other class in the
916	case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it	935	case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it
917	will be C<urxvt::anyevent>).	936	will be C<urxvt::anyevent>).
918		937
919	=item AnyEvent::detect	938	=item AnyEvent::detect
920		939
921	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model	940	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model
922	if necessary. You should only call this function right before you would	941	if necessary. You should only call this function right before you would
923	have created an AnyEvent watcher anyway, that is, as late as possible at	942	have created an AnyEvent watcher anyway, that is, as late as possible at
924	runtime, and not e.g. while initialising of your module.	943	runtime, and not e.g. during initialisation of your module.
		944
		945	The effect of calling this function is as if a watcher had been created
		946	(specifically, actions that happen "when the first watcher is created"
		947	happen when calling detetc as well).
925		948
926	If you need to do some initialisation before AnyEvent watchers are	949	If you need to do some initialisation before AnyEvent watchers are
927	created, use C<post_detect>.	950	created, use C<post_detect>.
928		951
929	=item $guard = AnyEvent::post_detect { BLOCK }	952	=item $guard = AnyEvent::post_detect { BLOCK }
930		953
931	Arranges for the code block to be executed as soon as the event model is	954	Arranges for the code block to be executed as soon as the event model is
932	autodetected (or immediately if this has already happened).	955	autodetected (or immediately if that has already happened).
933		956
934	The block will be executed I<after> the actual backend has been detected	957	The block will be executed I<after> the actual backend has been detected
935	(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been	958	(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been
936	created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do	959	created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do
937	other initialisations - see the sources of L<AnyEvent::Strict> or	960	other initialisations - see the sources of L<AnyEvent::Strict> or
…		…
946	that automatically removes the callback again when it is destroyed (or	969	that automatically removes the callback again when it is destroyed (or
947	C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for	970	C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for
948	a case where this is useful.	971	a case where this is useful.
949		972
950	Example: Create a watcher for the IO::AIO module and store it in	973	Example: Create a watcher for the IO::AIO module and store it in
951	C<$WATCHER>. Only do so after the event loop is initialised, though.	974	C<$WATCHER>, but do so only do so after the event loop is initialised.
952		975
953	our WATCHER;	976	our WATCHER;
954		977
955	my $guard = AnyEvent::post_detect {	978	my $guard = AnyEvent::post_detect {
956	$WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb);	979	$WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb);
…		…
964	$WATCHER ||= $guard;	987	$WATCHER ||= $guard;
965		988
966	=item @AnyEvent::post_detect	989	=item @AnyEvent::post_detect
967		990
968	If there are any code references in this array (you can C<push> to it	991	If there are any code references in this array (you can C<push> to it
969	before or after loading AnyEvent), then they will called directly after	992	before or after loading AnyEvent), then they will be called directly
970	the event loop has been chosen.	993	after the event loop has been chosen.
971		994
972	You should check C<$AnyEvent::MODEL> before adding to this array, though:	995	You should check C<$AnyEvent::MODEL> before adding to this array, though:
973	if it is defined then the event loop has already been detected, and the	996	if it is defined then the event loop has already been detected, and the
974	array will be ignored.	997	array will be ignored.
975		998
…		…
992	# AnyEvent not yet initialised, so make sure to load Coro::AnyEvent	1015	# AnyEvent not yet initialised, so make sure to load Coro::AnyEvent
993	# as soon as it is	1016	# as soon as it is
994	push @AnyEvent::post_detect, sub { require Coro::AnyEvent };	1017	push @AnyEvent::post_detect, sub { require Coro::AnyEvent };
995	}	1018	}
996		1019
		1020	=item AnyEvent::postpone { BLOCK }
		1021
		1022	Arranges for the block to be executed as soon as possible, but not before
		1023	the call itself returns. In practise, the block will be executed just
		1024	before the event loop polls for new events, or shortly afterwards.
		1025
		1026	This function never returns anything (to make the C<return postpone { ...
		1027	}> idiom more useful.
		1028
		1029	To understand the usefulness of this function, consider a function that
		1030	asynchronously does something for you and returns some transaction
		1031	object or guard to let you cancel the operation. For example,
		1032	C<AnyEvent::Socket::tcp_connect>:
		1033
		1034	# start a conenction attempt unless one is active
		1035	$self->{connect_guard} ||= AnyEvent::Socket::tcp_connect "www.example.net", 80, sub {
		1036	delete $self->{connect_guard};
		1037	...
		1038	};
		1039
		1040	Imagine that this function could instantly call the callback, for
		1041	example, because it detects an obvious error such as a negative port
		1042	number. Invoking the callback before the function returns causes problems
		1043	however: the callback will be called and will try to delete the guard
		1044	object. But since the function hasn't returned yet, there is nothing to
		1045	delete. When the function eventually returns it will assign the guard
		1046	object to C<< $self->{connect_guard} >>, where it will likely never be
		1047	deleted, so the program thinks it is still trying to connect.
		1048
		1049	This is where C<AnyEvent::postpone> should be used. Instead of calling the
		1050	callback directly on error:
		1051
		1052	$cb->(undef), return # signal error to callback, BAD!
		1053	if $some_error_condition;
		1054
		1055	It should use C<postpone>:
		1056
		1057	AnyEvent::postpone { $cb->(undef) }, return # signal error to callback, later
		1058	if $some_error_condition;
		1059
		1060	=item AnyEvent::log $level, $msg[, @args]
		1061
		1062	Log the given C<$msg> at the given C<$level>.
		1063
		1064	If L<AnyEvent::Log> is not loaded then this function makes a simple test
		1065	to see whether the message will be logged. If the test succeeds it will
		1066	load AnyEvent::Log and call C<AnyEvent::Log::log> - consequently, look at
		1067	the L<AnyEvent::Log> documentation for details.
		1068
		1069	If the test fails it will simply return. Right now this happens when a
		1070	numerical loglevel is used and it is larger than the level specified via
		1071	C<$ENV{PERL_ANYEVENT_VERBOSE}>.
		1072
		1073	If you want to sprinkle loads of logging calls around your code, consider
		1074	creating a logger callback with the C<AnyEvent::Log::logger> function,
		1075	which can reduce typing, codesize and can reduce the logging overhead
		1076	enourmously.
		1077
997	=back	1078	=back
998		1079
999	=head1 WHAT TO DO IN A MODULE	1080	=head1 WHAT TO DO IN A MODULE
1000		1081
1001	As a module author, you should C<use AnyEvent> and call AnyEvent methods	1082	As a module author, you should C<use AnyEvent> and call AnyEvent methods
…		…
1011	because it will stall the whole program, and the whole point of using	1092	because it will stall the whole program, and the whole point of using
1012	events is to stay interactive.	1093	events is to stay interactive.
1013		1094
1014	It is fine, however, to call C<< ->recv >> when the user of your module	1095	It is fine, however, to call C<< ->recv >> when the user of your module
1015	requests it (i.e. if you create a http request object ad have a method	1096	requests it (i.e. if you create a http request object ad have a method
1016	called C<results> that returns the results, it should call C<< ->recv >>	1097	called C<results> that returns the results, it may call C<< ->recv >>
1017	freely, as the user of your module knows what she is doing. always).	1098	freely, as the user of your module knows what she is doing. Always).
1018		1099
1019	=head1 WHAT TO DO IN THE MAIN PROGRAM	1100	=head1 WHAT TO DO IN THE MAIN PROGRAM
1020		1101
1021	There will always be a single main program - the only place that should	1102	There will always be a single main program - the only place that should
1022	dictate which event model to use.	1103	dictate which event model to use.
1023		1104
1024	If it doesn't care, it can just "use AnyEvent" and use it itself, or not	1105	If the program is not event-based, it need not do anything special, even
1025	do anything special (it does not need to be event-based) and let AnyEvent	1106	when it depends on a module that uses an AnyEvent. If the program itself
1026	decide which implementation to chose if some module relies on it.	1107	uses AnyEvent, but does not care which event loop is used, all it needs
		1108	to do is C<use AnyEvent>. In either case, AnyEvent will choose the best
		1109	available loop implementation.
1027		1110
1028	If the main program relies on a specific event model - for example, in	1111	If the main program relies on a specific event model - for example, in
1029	Gtk2 programs you have to rely on the Glib module - you should load the	1112	Gtk2 programs you have to rely on the Glib module - you should load the
1030	event module before loading AnyEvent or any module that uses it: generally	1113	event module before loading AnyEvent or any module that uses it: generally
1031	speaking, you should load it as early as possible. The reason is that	1114	speaking, you should load it as early as possible. The reason is that
1032	modules might create watchers when they are loaded, and AnyEvent will	1115	modules might create watchers when they are loaded, and AnyEvent will
1033	decide on the event model to use as soon as it creates watchers, and it	1116	decide on the event model to use as soon as it creates watchers, and it
1034	might chose the wrong one unless you load the correct one yourself.	1117	might choose the wrong one unless you load the correct one yourself.
1035		1118
1036	You can chose to use a pure-perl implementation by loading the	1119	You can chose to use a pure-perl implementation by loading the
1037	C<AnyEvent::Impl::Perl> module, which gives you similar behaviour	1120	C<AnyEvent::Loop> module, which gives you similar behaviour
1038	everywhere, but letting AnyEvent chose the model is generally better.	1121	everywhere, but letting AnyEvent chose the model is generally better.
1039		1122
1040	=head2 MAINLOOP EMULATION	1123	=head2 MAINLOOP EMULATION
1041		1124
1042	Sometimes (often for short test scripts, or even standalone programs who	1125	Sometimes (often for short test scripts, or even standalone programs who
…		…
1055		1138
1056		1139
1057	=head1 OTHER MODULES	1140	=head1 OTHER MODULES
1058		1141
1059	The following is a non-exhaustive list of additional modules that use	1142	The following is a non-exhaustive list of additional modules that use
1060	AnyEvent as a client and can therefore be mixed easily with other AnyEvent	1143	AnyEvent as a client and can therefore be mixed easily with other
1061	modules and other event loops in the same program. Some of the modules	1144	AnyEvent modules and other event loops in the same program. Some of the
1062	come with AnyEvent, most are available via CPAN.	1145	modules come as part of AnyEvent, the others are available via CPAN (see
		1146	L<http://search.cpan.org/search?m=module&q=anyevent%3A%3A*> for
		1147	a longer non-exhaustive list), and the list is heavily biased towards
		1148	modules of the AnyEvent author himself :)
1063		1149
1064	=over 4	1150	=over 4
1065		1151
1066	=item L<AnyEvent::Util>	1152	=item L<AnyEvent::Util> (part of the AnyEvent distribution)
1067		1153
1068	Contains various utility functions that replace often-used but blocking	1154	Contains various utility functions that replace often-used blocking
1069	functions such as C<inet_aton> by event-/callback-based versions.	1155	functions such as C<inet_aton> with event/callback-based versions.
1070		1156
1071	=item L<AnyEvent::Socket>	1157	=item L<AnyEvent::Socket> (part of the AnyEvent distribution)
1072		1158
1073	Provides various utility functions for (internet protocol) sockets,	1159	Provides various utility functions for (internet protocol) sockets,
1074	addresses and name resolution. Also functions to create non-blocking tcp	1160	addresses and name resolution. Also functions to create non-blocking tcp
1075	connections or tcp servers, with IPv6 and SRV record support and more.	1161	connections or tcp servers, with IPv6 and SRV record support and more.
1076		1162
1077	=item L<AnyEvent::Handle>	1163	=item L<AnyEvent::Handle> (part of the AnyEvent distribution)
1078		1164
1079	Provide read and write buffers, manages watchers for reads and writes,	1165	Provide read and write buffers, manages watchers for reads and writes,
1080	supports raw and formatted I/O, I/O queued and fully transparent and	1166	supports raw and formatted I/O, I/O queued and fully transparent and
1081	non-blocking SSL/TLS (via L<AnyEvent::TLS>.	1167	non-blocking SSL/TLS (via L<AnyEvent::TLS>).
1082		1168
1083	=item L<AnyEvent::DNS>	1169	=item L<AnyEvent::DNS> (part of the AnyEvent distribution)
1084		1170
1085	Provides rich asynchronous DNS resolver capabilities.	1171	Provides rich asynchronous DNS resolver capabilities.
1086		1172
		1173	=item L<AnyEvent::HTTP>, L<AnyEvent::IRC>, L<AnyEvent::XMPP>, L<AnyEvent::GPSD>, L<AnyEvent::IGS>, L<AnyEvent::FCP>
		1174
		1175	Implement event-based interfaces to the protocols of the same name (for
		1176	the curious, IGS is the International Go Server and FCP is the Freenet
		1177	Client Protocol).
		1178
		1179	=item L<AnyEvent::AIO> (part of the AnyEvent distribution)
		1180
		1181	Truly asynchronous (as opposed to non-blocking) I/O, should be in the
		1182	toolbox of every event programmer. AnyEvent::AIO transparently fuses
		1183	L<IO::AIO> and AnyEvent together, giving AnyEvent access to event-based
		1184	file I/O, and much more.
		1185
		1186	=item L<AnyEvent::Filesys::Notify>
		1187
		1188	AnyEvent is good for non-blocking stuff, but it can't detect file or
		1189	path changes (e.g. "watch this directory for new files", "watch this
		1190	file for changes"). The L<AnyEvent::Filesys::Notify> module promises to
		1191	do just that in a portbale fashion, supporting inotify on GNU/Linux and
		1192	some weird, without doubt broken, stuff on OS X to monitor files. It can
		1193	fall back to blocking scans at regular intervals transparently on other
		1194	platforms, so it's about as portable as it gets.
		1195
		1196	(I haven't used it myself, but I haven't heard anybody complaining about
		1197	it yet).
		1198
1087	=item L<AnyEvent::HTTP>	1199	=item L<AnyEvent::DBI>
1088		1200
1089	A simple-to-use HTTP library that is capable of making a lot of concurrent	1201	Executes L<DBI> requests asynchronously in a proxy process for you,
1090	HTTP requests.	1202	notifying you in an event-based way when the operation is finished.
1091		1203
1092	=item L<AnyEvent::HTTPD>	1204	=item L<AnyEvent::HTTPD>
1093		1205
1094	Provides a simple web application server framework.	1206	A simple embedded webserver.
1095		1207
1096	=item L<AnyEvent::FastPing>	1208	=item L<AnyEvent::FastPing>
1097		1209
1098	The fastest ping in the west.	1210	The fastest ping in the west.
1099		1211
1100	=item L<AnyEvent::DBI>
1101
1102	Executes L<DBI> requests asynchronously in a proxy process.
1103
1104	=item L<AnyEvent::AIO>
1105
1106	Truly asynchronous I/O, should be in the toolbox of every event
1107	programmer. AnyEvent::AIO transparently fuses L<IO::AIO> and AnyEvent
1108	together.
1109
1110	=item L<AnyEvent::BDB>
1111
1112	Truly asynchronous Berkeley DB access. AnyEvent::BDB transparently fuses
1113	L<BDB> and AnyEvent together.
1114
1115	=item L<AnyEvent::GPSD>
1116
1117	A non-blocking interface to gpsd, a daemon delivering GPS information.
1118
1119	=item L<AnyEvent::IRC>
1120
1121	AnyEvent based IRC client module family (replacing the older Net::IRC3).
1122
1123	=item L<AnyEvent::XMPP>
1124
1125	AnyEvent based XMPP (Jabber protocol) module family (replacing the older
1126	Net::XMPP2>.
1127
1128	=item L<AnyEvent::IGS>
1129
1130	A non-blocking interface to the Internet Go Server protocol (used by
1131	L<App::IGS>).
1132
1133	=item L<Net::FCP>
1134
1135	AnyEvent-based implementation of the Freenet Client Protocol, birthplace
1136	of AnyEvent.
1137
1138	=item L<Event::ExecFlow>
1139
1140	High level API for event-based execution flow control.
1141
1142	=item L<Coro>	1212	=item L<Coro>
1143		1213
1144	Has special support for AnyEvent via L<Coro::AnyEvent>.	1214	Has special support for AnyEvent via L<Coro::AnyEvent>, which allows you
		1215	to simply invert the flow control - don't call us, we will call you:
		1216
		1217	async {
		1218	Coro::AnyEvent::sleep 5; # creates a 5s timer and waits for it
		1219	print "5 seconds later!\n";
		1220
		1221	Coro::AnyEvent::readable *STDIN; # uses an I/O watcher
		1222	my $line = <STDIN>; # works for ttys
		1223
		1224	AnyEvent::HTTP::http_get "url", Coro::rouse_cb;
		1225	my ($body, $hdr) = Coro::rouse_wait;
		1226	};
1145		1227
1146	=back	1228	=back
1147		1229
1148	=cut	1230	=cut
1149		1231
1150	package AnyEvent;	1232	package AnyEvent;
1151
1152	# basically a tuned-down version of common::sense
1153	sub common_sense {
1154	# from common:.sense 1.0
1155	${^WARNING_BITS} = "\xfc\x3f\x33\x00\x0f\xf3\xcf\xc0\xf3\xfc\x33\x00";
1156	# use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl)
1157	$^H |= 0x00000600;
1158	}
1159
1160	BEGIN { AnyEvent::common_sense }
1161
1162	use Carp ();
1163
1164	our $VERSION = '5.26';
1165	our $MODEL;
1166
1167	our $AUTOLOAD;
1168	our @ISA;
1169
1170	our @REGISTRY;
1171
1172	our $VERBOSE;
1173		1233
1174	BEGIN {	1234	BEGIN {
1175	require "AnyEvent/constants.pl";	1235	require "AnyEvent/constants.pl";
		1236	&AnyEvent::common_sense;
		1237	}
1176		1238
		1239	use Carp ();
		1240
		1241	our $VERSION = '7.05';
		1242	our $MODEL;
		1243	our @ISA;
		1244	our @REGISTRY;
		1245	our $VERBOSE;
		1246	our %PROTOCOL; # (ipv4|ipv6) => (1|2), higher numbers are preferred
		1247	our $MAX_SIGNAL_LATENCY = $ENV{PERL_ANYEVENT_MAX_SIGNAL_LATENCY} || 10; # executes after the BEGIN block below (tainting!)
		1248
		1249	BEGIN {
1177	eval "sub TAINT (){" . (${^TAINT}*1) . "}";	1250	eval "sub TAINT (){" . (${^TAINT}*1) . "}";
1178		1251
1179	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}	1252	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}
1180	if ${^TAINT};	1253	if ${^TAINT};
1181		1254
1182	$VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1;	1255	$ENV{"PERL_ANYEVENT_$_"} = $ENV{"AE_$_"}
		1256	for grep s/^AE_// && !exists $ENV{"PERL_ANYEVENT_$_"}, keys %ENV;
1183		1257
1184	}	1258	@ENV{grep /^PERL_ANYEVENT_/, keys %ENV} = ()
		1259	if ${^TAINT};
1185		1260
1186	our $MAX_SIGNAL_LATENCY = 10;	1261	# $ENV{PERL_ANYEVENT_xxx} now valid
1187		1262
1188	our %PROTOCOL; # (ipv4|ipv6) => (1|2), higher numbers are preferred	1263	$VERBOSE = length $ENV{PERL_ANYEVENT_VERBOSE} ? $ENV{PERL_ANYEVENT_VERBOSE}*1 : 4;
1189		1264
1190	{
1191	my $idx;	1265	my $idx;
1192	$PROTOCOL{$_} = ++$idx	1266	$PROTOCOL{$_} = ++$idx
1193	for reverse split /\s*,\s*/,	1267	for reverse split /\s*,\s*/,
1194	$ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6";	1268	$ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6";
1195	}	1269	}
1196		1270
		1271	our @post_detect;
		1272
		1273	sub post_detect(&) {
		1274	my ($cb) = @_;
		1275
		1276	push @post_detect, $cb;
		1277
		1278	defined wantarray
		1279	? bless \$cb, "AnyEvent::Util::postdetect"
		1280	: ()
		1281	}
		1282
		1283	sub AnyEvent::Util::postdetect::DESTROY {
		1284	@post_detect = grep $_ != ${$_[0]}, @post_detect;
		1285	}
		1286
		1287	our $POSTPONE_W;
		1288	our @POSTPONE;
		1289
		1290	sub _postpone_exec {
		1291	undef $POSTPONE_W;
		1292
		1293	&{ shift @POSTPONE }
		1294	while @POSTPONE;
		1295	}
		1296
		1297	sub postpone(&) {
		1298	push @POSTPONE, shift;
		1299
		1300	$POSTPONE_W ||= AE::timer (0, 0, \&_postpone_exec);
		1301
		1302	()
		1303	}
		1304
		1305	sub log($$;@) {
		1306	# only load the big bloated module when we actually are about to log something
		1307	if ($_[0] <= ($VERBOSE || 1)) { # also catches non-numeric levels(!) and fatal
		1308	local ($!, $@);
		1309	require AnyEvent::Log; # among other things, sets $VERBOSE to 9
		1310	# AnyEvent::Log overwrites this function
		1311	goto &log;
		1312	}
		1313
		1314	0 # not logged
		1315	}
		1316
		1317	sub _logger($;$) {
		1318	my ($level, $renabled) = @_;
		1319
		1320	$$renabled = $level <= $VERBOSE;
		1321
		1322	my $logger = [(caller)[0], $level, $renabled];
		1323
		1324	$AnyEvent::Log::LOGGER{$logger+0} = $logger;
		1325
		1326	# return unless defined wantarray;
		1327	#
		1328	# require AnyEvent::Util;
		1329	# my $guard = AnyEvent::Util::guard (sub {
		1330	# # "clean up"
		1331	# delete $LOGGER{$logger+0};
		1332	# });
		1333	#
		1334	# sub {
		1335	# return 0 unless $$renabled;
		1336	#
		1337	# $guard if 0; # keep guard alive, but don't cause runtime overhead
		1338	# require AnyEvent::Log unless $AnyEvent::Log::VERSION;
		1339	# package AnyEvent::Log;
		1340	# _log ($logger->[0], $level, @_) # logger->[0] has been converted at load time
		1341	# }
		1342	}
		1343
		1344	if (length $ENV{PERL_ANYEVENT_LOG}) {
		1345	require AnyEvent::Log; # AnyEvent::Log does the thing for us
		1346	}
		1347
1197	my @models = (	1348	our @models = (
1198	[EV:: => AnyEvent::Impl::EV:: , 1],	1349	[EV:: => AnyEvent::Impl::EV::],
1199	[AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl:: , 1],	1350	[AnyEvent::Loop:: => AnyEvent::Impl::Perl::],
1200	# everything below here will not (normally) be autoprobed	1351	# everything below here will not (normally) be autoprobed
1201	# as the pureperl backend should work everywhere	1352	# as the pure perl backend should work everywhere
1202	# and is usually faster	1353	# and is usually faster
		1354	[Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package, so msut be near the top
1203	[Event:: => AnyEvent::Impl::Event::, 1],	1355	[Event:: => AnyEvent::Impl::Event::], # slow, stable
1204	[Glib:: => AnyEvent::Impl::Glib:: , 1], # becomes extremely slow with many watchers	1356	[Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers
		1357	# everything below here should not be autoloaded
1205	[Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy	1358	[Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
1206	[Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package
1207	[Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles	1359	[Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
1208	[Qt:: => AnyEvent::Impl::Qt::], # requires special main program	1360	[Qt:: => AnyEvent::Impl::Qt::], # requires special main program
1209	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza	1361	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
1210	[Wx:: => AnyEvent::Impl::POE::],	1362	[Wx:: => AnyEvent::Impl::POE::],
1211	[Prima:: => AnyEvent::Impl::POE::],	1363	[Prima:: => AnyEvent::Impl::POE::],
1212	# IO::Async is just too broken - we would need workarounds for its	1364	[IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # a bitch to autodetect
1213	# byzantine signal and broken child handling, among others.	1365	[Cocoa::EventLoop:: => AnyEvent::Impl::Cocoa::],
1214	# IO::Async is rather hard to detect, as it doesn't have any	1366	[FLTK:: => AnyEvent::Impl::FLTK::],
1215	# obvious default class.
1216	[IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program
1217	[IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program
1218	[IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program
1219	[AnyEvent::Impl::IOAsync:: => AnyEvent::Impl::IOAsync::], # requires special main program
1220	);	1367	);
1221		1368
1222	our %method = map +($_ => 1),	1369	our @isa_hook;
		1370
		1371	sub _isa_set {
		1372	my @pkg = ("AnyEvent", (map $_->[0], grep defined, @isa_hook), $MODEL);
		1373
		1374	@{"$pkg[$_-1]::ISA"} = $pkg[$_]
		1375	for 1 .. $#pkg;
		1376
		1377	grep $_ && $_->[1], @isa_hook
		1378	and AE::_reset ();
		1379	}
		1380
		1381	# used for hooking AnyEvent::Strict and AnyEvent::Debug::Wrap into the class hierarchy
		1382	sub _isa_hook($$;$) {
		1383	my ($i, $pkg, $reset_ae) = @_;
		1384
		1385	$isa_hook[$i] = $pkg ? [$pkg, $reset_ae] : undef;
		1386
		1387	_isa_set;
		1388	}
		1389
		1390	# all autoloaded methods reserve the complete glob, not just the method slot.
		1391	# due to bugs in perls method cache implementation.
1223	qw(io timer time now now_update signal child idle condvar one_event DESTROY);	1392	our @methods = qw(io timer time now now_update signal child idle condvar);
1224
1225	our @post_detect;
1226
1227	sub post_detect(&) {
1228	my ($cb) = @_;
1229
1230	push @post_detect, $cb;
1231
1232	defined wantarray
1233	? bless \$cb, "AnyEvent::Util::postdetect"
1234	: ()
1235	}
1236
1237	sub AnyEvent::Util::postdetect::DESTROY {
1238	@post_detect = grep $_ != ${$_[0]}, @post_detect;
1239	}
1240		1393
1241	sub detect() {	1394	sub detect() {
		1395	return $MODEL if $MODEL; # some programs keep references to detect
		1396
		1397	# IO::Async::Loop::AnyEvent is extremely evil, refuse to work with it
		1398	# the author knows about the problems and what it does to AnyEvent as a whole
		1399	# (and the ability of others to use AnyEvent), but simply wants to abuse AnyEvent
		1400	# anyway.
		1401	AnyEvent::log fatal => "IO::Async::Loop::AnyEvent detected - that module is broken by\n"
		1402	. "design, abuses internals and breaks AnyEvent - will not continue."
		1403	if exists $INC{"IO/Async/Loop/AnyEvent.pm"};
		1404
		1405	local $!; # for good measure
		1406	local $SIG{__DIE__}; # we use eval
		1407
1242	# free some memory	1408	# free some memory
1243	*detect = sub () { $MODEL };	1409	*detect = sub () { $MODEL };
		1410	# undef &func doesn't correctly update the method cache. grmbl.
		1411	# so we delete the whole glob. grmbl.
		1412	# otoh, perl doesn't let me undef an active usb, but it lets me free
		1413	# a glob with an active sub. hrm. i hope it works, but perl is
		1414	# usually buggy in this department. sigh.
		1415	delete @{"AnyEvent::"}{@methods};
		1416	undef @methods;
1244		1417
1245	local $!; # for good measure
1246	local $SIG{__DIE__};
1247
1248	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {	1418	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z0-9:]+)$/) {
1249	my $model = "AnyEvent::Impl::$1";	1419	my $model = $1;
		1420	$model = "AnyEvent::Impl::$model" unless $model =~ s/::$//;
1250	if (eval "require $model") {	1421	if (eval "require $model") {
		1422	AnyEvent::log 7 => "Loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.";
1251	$MODEL = $model;	1423	$MODEL = $model;
1252	warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2;
1253	} else {	1424	} else {
1254	warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE;	1425	AnyEvent::log 4 => "Unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@";
1255	}	1426	}
1256	}	1427	}
1257		1428
1258	# check for already loaded models	1429	# check for already loaded models
1259	unless ($MODEL) {	1430	unless ($MODEL) {
1260	for (@REGISTRY, @models) {	1431	for (@REGISTRY, @models) {
1261	my ($package, $model) = @$_;	1432	my ($package, $model) = @$_;
1262	if (${"$package\::VERSION"} > 0) {	1433	if (${"$package\::VERSION"} > 0) {
1263	if (eval "require $model") {	1434	if (eval "require $model") {
		1435	AnyEvent::log 7 => "Autodetected model '$model', using it.";
1264	$MODEL = $model;	1436	$MODEL = $model;
1265	warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2;	1437	last;
		1438	} else {
		1439	AnyEvent::log 8 => "Detected event loop $package, but cannot load '$model', skipping: $@";
		1440	}
		1441	}
		1442	}
		1443
		1444	unless ($MODEL) {
		1445	# try to autoload a model
		1446	for (@REGISTRY, @models) {
		1447	my ($package, $model) = @$_;
		1448	if (
		1449	eval "require $package"
		1450	and ${"$package\::VERSION"} > 0
		1451	and eval "require $model"
		1452	) {
		1453	AnyEvent::log 7 => "Autoloaded model '$model', using it.";
		1454	$MODEL = $model;
1266	last;	1455	last;
1267	}	1456	}
1268	}	1457	}
1269	}
1270
1271	unless ($MODEL) {
1272	# try to autoload a model
1273	for (@REGISTRY, @models) {
1274	my ($package, $model, $autoload) = @$_;
1275	if (
1276	$autoload
1277	and eval "require $package"
1278	and ${"$package\::VERSION"} > 0
1279	and eval "require $model"
1280	) {
1281	$MODEL = $model;
1282	warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2;
1283	last;
1284	}
1285	}
1286		1458
1287	$MODEL	1459	$MODEL
1288	or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.\n";	1460	or AnyEvent::log fatal => "Backend autodetection failed - did you properly install AnyEvent?";
1289	}	1461	}
1290	}	1462	}
1291		1463
1292	@models = (); # free probe data	1464	# free memory only needed for probing
		1465	undef @models;
		1466	undef @REGISTRY;
1293		1467
1294	push @{"$MODEL\::ISA"}, "AnyEvent::Base";	1468	push @{"$MODEL\::ISA"}, "AnyEvent::Base";
1295	unshift @ISA, $MODEL;
1296		1469
1297	# now nuke some methods that are overriden by the backend.	1470	# now nuke some methods that are overridden by the backend.
1298	# SUPER is not allowed.	1471	# SUPER usage is not allowed in these.
1299	for (qw(time signal child idle)) {	1472	for (qw(time signal child idle)) {
1300	undef &{"AnyEvent::Base::$_"}	1473	undef &{"AnyEvent::Base::$_"}
1301	if defined &{"$MODEL\::$_"};	1474	if defined &{"$MODEL\::$_"};
1302	}	1475	}
1303		1476
1304	require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT};	1477	_isa_set;
		1478
		1479	# we're officially open!
		1480
		1481	if ($ENV{PERL_ANYEVENT_STRICT}) {
		1482	require AnyEvent::Strict;
		1483	}
		1484
		1485	if ($ENV{PERL_ANYEVENT_DEBUG_WRAP}) {
		1486	require AnyEvent::Debug;
		1487	AnyEvent::Debug::wrap ($ENV{PERL_ANYEVENT_DEBUG_WRAP});
		1488	}
		1489
		1490	if (length $ENV{PERL_ANYEVENT_DEBUG_SHELL}) {
		1491	require AnyEvent::Socket;
		1492	require AnyEvent::Debug;
		1493
		1494	my $shell = $ENV{PERL_ANYEVENT_DEBUG_SHELL};
		1495	$shell =~ s/\$\$/$$/g;
		1496
		1497	my ($host, $service) = AnyEvent::Socket::parse_hostport ($shell);
		1498	$AnyEvent::Debug::SHELL = AnyEvent::Debug::shell ($host, $service);
		1499	}
		1500
		1501	# now the anyevent environment is set up as the user told us to, so
		1502	# call the actual user code - post detects
1305		1503
1306	(shift @post_detect)->() while @post_detect;	1504	(shift @post_detect)->() while @post_detect;
		1505	undef @post_detect;
1307		1506
1308	*post_detect = sub(&) {	1507	*post_detect = sub(&) {
1309	shift->();	1508	shift->();
1310		1509
1311	undef	1510	undef
1312	};	1511	};
1313		1512
1314	$MODEL	1513	$MODEL
1315	}	1514	}
1316		1515
1317	sub AUTOLOAD {	1516	for my $name (@methods) {
1318	(my $func = $AUTOLOAD) =~ s/.*://;	1517	*$name = sub {
1319
1320	$method{$func}
1321	or Carp::croak "$func: not a valid AnyEvent class method";
1322
1323	detect;	1518	detect;
1324		1519	# we use goto because
1325	my $class = shift;	1520	# a) it makes the thunk more transparent
1326	$class->$func (@_);	1521	# b) it allows us to delete the thunk later
		1522	goto &{ UNIVERSAL::can AnyEvent => "SUPER::$name" }
		1523	};
1327	}	1524	}
1328		1525
1329	# utility function to dup a filehandle. this is used by many backends	1526	# utility function to dup a filehandle. this is used by many backends
1330	# to support binding more than one watcher per filehandle (they usually	1527	# to support binding more than one watcher per filehandle (they usually
1331	# allow only one watcher per fd, so we dup it to get a different one).	1528	# allow only one watcher per fd, so we dup it to get a different one).
…		…
1355		1552
1356	package AE;	1553	package AE;
1357		1554
1358	our $VERSION = $AnyEvent::VERSION;	1555	our $VERSION = $AnyEvent::VERSION;
1359		1556
		1557	sub _reset() {
		1558	eval q{
1360	# fall back to the main API by default - backends and AnyEvent::Base	1559	# fall back to the main API by default - backends and AnyEvent::Base
1361	# implementations can overwrite these.	1560	# implementations can overwrite these.
1362		1561
1363	sub io($$$) {	1562	sub io($$$) {
1364	AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])	1563	AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])
1365	}	1564	}
1366		1565
1367	sub timer($$$) {	1566	sub timer($$$) {
1368	AnyEvent->timer (after => $_[0], interval => $_[1], cb => $_[2])	1567	AnyEvent->timer (after => $_[0], interval => $_[1], cb => $_[2])
1369	}	1568	}
1370		1569
1371	sub signal($$) {	1570	sub signal($$) {
1372	AnyEvent->signal (signal => $_[0], cb => $_[1])	1571	AnyEvent->signal (signal => $_[0], cb => $_[1])
1373	}	1572	}
1374		1573
1375	sub child($$) {	1574	sub child($$) {
1376	AnyEvent->child (pid => $_[0], cb => $_[1])	1575	AnyEvent->child (pid => $_[0], cb => $_[1])
1377	}	1576	}
1378		1577
1379	sub idle($) {	1578	sub idle($) {
1380	AnyEvent->idle (cb => $_[0])	1579	AnyEvent->idle (cb => $_[0]);
1381	}	1580	}
1382		1581
1383	sub cv(;&) {	1582	sub cv(;&) {
1384	AnyEvent->condvar (@_ ? (cb => $_[0]) : ())	1583	AnyEvent->condvar (@_ ? (cb => $_[0]) : ())
1385	}	1584	}
1386		1585
1387	sub now() {	1586	sub now() {
1388	AnyEvent->now	1587	AnyEvent->now
1389	}	1588	}
1390		1589
1391	sub now_update() {	1590	sub now_update() {
1392	AnyEvent->now_update	1591	AnyEvent->now_update
1393	}	1592	}
1394		1593
1395	sub time() {	1594	sub time() {
1396	AnyEvent->time	1595	AnyEvent->time
		1596	}
		1597
		1598	*postpone = \&AnyEvent::postpone;
		1599	*log = \&AnyEvent::log;
		1600	};
		1601	die if $@;
1397	}	1602	}
		1603
		1604	BEGIN { _reset }
1398		1605
1399	package AnyEvent::Base;	1606	package AnyEvent::Base;
1400		1607
1401	# default implementations for many methods	1608	# default implementations for many methods
1402		1609
1403	sub time {	1610	sub time {
1404	eval q{ # poor man's autoloading {}	1611	eval q{ # poor man's autoloading {}
1405	# probe for availability of Time::HiRes	1612	# probe for availability of Time::HiRes
1406	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {	1613	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
1407	warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8;	1614	*time = sub { Time::HiRes::time () };
1408	*AE::time = \&Time::HiRes::time;	1615	*AE::time = \& Time::HiRes::time ;
		1616	*now = \&time;
		1617	AnyEvent::log 8 => "using Time::HiRes for sub-second timing accuracy.";
1409	# if (eval "use POSIX (); (POSIX::times())...	1618	# if (eval "use POSIX (); (POSIX::times())...
1410	} else {	1619	} else {
1411	warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE;	1620	*time = sub { CORE::time };
1412	*AE::time = sub (){ time }; # epic fail	1621	*AE::time = sub (){ CORE::time };
		1622	*now = \&time;
		1623	AnyEvent::log 3 => "Using built-in time(), no sub-second resolution!";
1413	}	1624	}
1414
1415	*time = sub { AE::time }; # different prototypes
1416	};	1625	};
1417	die if $@;	1626	die if $@;
1418		1627
1419	&time	1628	&time
1420	}	1629	}
1421		1630
1422	*now = \&time;	1631	*now = \&time;
1423
1424	sub now_update { }	1632	sub now_update { }
1425		1633
		1634	sub _poll {
		1635	Carp::croak "$AnyEvent::MODEL does not support blocking waits. Caught";
		1636	}
		1637
1426	# default implementation for ->condvar	1638	# default implementation for ->condvar
		1639	# in fact, the default should not be overwritten
1427		1640
1428	sub condvar {	1641	sub condvar {
1429	eval q{ # poor man's autoloading {}	1642	eval q{ # poor man's autoloading {}
1430	*condvar = sub {	1643	*condvar = sub {
1431	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"	1644	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"
…		…
1509		1722
1510	sub signal {	1723	sub signal {
1511	eval q{ # poor man's autoloading {}	1724	eval q{ # poor man's autoloading {}
1512	# probe for availability of Async::Interrupt	1725	# probe for availability of Async::Interrupt
1513	if (_have_async_interrupt) {	1726	if (_have_async_interrupt) {
1514	warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8;	1727	AnyEvent::log 8 => "Using Async::Interrupt for race-free signal handling.";
1515		1728
1516	$SIGPIPE_R = new Async::Interrupt::EventPipe;	1729	$SIGPIPE_R = new Async::Interrupt::EventPipe;
1517	$SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;	1730	$SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;
1518		1731
1519	} else {	1732	} else {
1520	warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;	1733	AnyEvent::log 8 => "Using emulated perl signal handling with latency timer.";
1521		1734
1522	if (AnyEvent::WIN32) {	1735	if (AnyEvent::WIN32) {
1523	require AnyEvent::Util;	1736	require AnyEvent::Util;
1524		1737
1525	($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();	1738	($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
…		…
1601	: sysread $SIGPIPE_R, (my $dummy), 9;	1814	: sysread $SIGPIPE_R, (my $dummy), 9;
1602		1815
1603	while (%SIG_EV) {	1816	while (%SIG_EV) {
1604	for (keys %SIG_EV) {	1817	for (keys %SIG_EV) {
1605	delete $SIG_EV{$_};	1818	delete $SIG_EV{$_};
1606	$_->() for values %{ $SIG_CB{$_} || {} };	1819	&$_ for values %{ $SIG_CB{$_} || {} };
1607	}	1820	}
1608	}	1821	}
1609	};	1822	};
1610	};	1823	};
1611	die if $@;	1824	die if $@;
…		…
1616	# default implementation for ->child	1829	# default implementation for ->child
1617		1830
1618	our %PID_CB;	1831	our %PID_CB;
1619	our $CHLD_W;	1832	our $CHLD_W;
1620	our $CHLD_DELAY_W;	1833	our $CHLD_DELAY_W;
1621	our $WNOHANG;
1622		1834
1623	# used by many Impl's	1835	# used by many Impl's
1624	sub _emit_childstatus($$) {	1836	sub _emit_childstatus($$) {
1625	my (undef, $rpid, $rstatus) = @_;	1837	my (undef, $rpid, $rstatus) = @_;
1626		1838
…		…
1633	eval q{ # poor man's autoloading {}	1845	eval q{ # poor man's autoloading {}
1634	*_sigchld = sub {	1846	*_sigchld = sub {
1635	my $pid;	1847	my $pid;
1636		1848
1637	AnyEvent->_emit_childstatus ($pid, $?)	1849	AnyEvent->_emit_childstatus ($pid, $?)
1638	while ($pid = waitpid -1, $WNOHANG) > 0;	1850	while ($pid = waitpid -1, WNOHANG) > 0;
1639	};	1851	};
1640		1852
1641	*child = sub {	1853	*child = sub {
1642	my (undef, %arg) = @_;	1854	my (undef, %arg) = @_;
1643		1855
1644	defined (my $pid = $arg{pid} + 0)	1856	my $pid = $arg{pid};
1645	or Carp::croak "required option 'pid' is missing";	1857	my $cb = $arg{cb};
1646		1858
1647	$PID_CB{$pid}{$arg{cb}} = $arg{cb};	1859	$PID_CB{$pid}{$cb+0} = $cb;
1648
1649	# WNOHANG is almost cetrainly 1 everywhere
1650	$WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/
1651	? 1
1652	: eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1;
1653		1860
1654	unless ($CHLD_W) {	1861	unless ($CHLD_W) {
1655	$CHLD_W = AE::signal CHLD => \&_sigchld;	1862	$CHLD_W = AE::signal CHLD => \&_sigchld;
1656	# child could be a zombie already, so make at least one round	1863	# child could be a zombie already, so make at least one round
1657	&_sigchld;	1864	&_sigchld;
1658	}	1865	}
1659		1866
1660	bless [$pid, $arg{cb}], "AnyEvent::Base::child"	1867	bless [$pid, $cb+0], "AnyEvent::Base::child"
1661	};	1868	};
1662		1869
1663	*AnyEvent::Base::child::DESTROY = sub {	1870	*AnyEvent::Base::child::DESTROY = sub {
1664	my ($pid, $cb) = @{$_[0]};	1871	my ($pid, $icb) = @{$_[0]};
1665		1872
1666	delete $PID_CB{$pid}{$cb};	1873	delete $PID_CB{$pid}{$icb};
1667	delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };	1874	delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };
1668		1875
1669	undef $CHLD_W unless keys %PID_CB;	1876	undef $CHLD_W unless keys %PID_CB;
1670	};	1877	};
1671	};	1878	};
…		…
1684		1891
1685	my ($cb, $w, $rcb) = $arg{cb};	1892	my ($cb, $w, $rcb) = $arg{cb};
1686		1893
1687	$rcb = sub {	1894	$rcb = sub {
1688	if ($cb) {	1895	if ($cb) {
1689	$w = _time;	1896	$w = AE::time;
1690	&$cb;	1897	&$cb;
1691	$w = _time - $w;	1898	$w = AE::time - $w;
1692		1899
1693	# never use more then 50% of the time for the idle watcher,	1900	# never use more then 50% of the time for the idle watcher,
1694	# within some limits	1901	# within some limits
1695	$w = 0.0001 if $w < 0.0001;	1902	$w = 0.0001 if $w < 0.0001;
1696	$w = 5 if $w > 5;	1903	$w = 5 if $w > 5;
…		…
1719		1926
1720	package AnyEvent::CondVar;	1927	package AnyEvent::CondVar;
1721		1928
1722	our @ISA = AnyEvent::CondVar::Base::;	1929	our @ISA = AnyEvent::CondVar::Base::;
1723		1930
		1931	# only to be used for subclassing
		1932	sub new {
		1933	my $class = shift;
		1934	bless AnyEvent->condvar (@_), $class
		1935	}
		1936
1724	package AnyEvent::CondVar::Base;	1937	package AnyEvent::CondVar::Base;
1725		1938
1726	#use overload	1939	#use overload
1727	# '&{}' => sub { my $self = shift; sub { $self->send (@_) } },	1940	# '&{}' => sub { my $self = shift; sub { $self->send (@_) } },
1728	# fallback => 1;	1941	# fallback => 1;
…		…
1737		1950
1738	sub _send {	1951	sub _send {
1739	# nop	1952	# nop
1740	}	1953	}
1741		1954
		1955	sub _wait {
		1956	AnyEvent->_poll until $_[0]{_ae_sent};
		1957	}
		1958
1742	sub send {	1959	sub send {
1743	my $cv = shift;	1960	my $cv = shift;
1744	$cv->{_ae_sent} = [@_];	1961	$cv->{_ae_sent} = [@_];
1745	(delete $cv->{_ae_cb})->($cv) if $cv->{_ae_cb};	1962	(delete $cv->{_ae_cb})->($cv) if $cv->{_ae_cb};
1746	$cv->_send;	1963	$cv->_send;
…		…
1753		1970
1754	sub ready {	1971	sub ready {
1755	$_[0]{_ae_sent}	1972	$_[0]{_ae_sent}
1756	}	1973	}
1757		1974
1758	sub _wait {
1759	$WAITING
1760	and !$_[0]{_ae_sent}
1761	and Carp::croak "AnyEvent::CondVar: recursive blocking wait detected";
1762
1763	local $WAITING = 1;
1764	AnyEvent->one_event while !$_[0]{_ae_sent};
1765	}
1766
1767	sub recv {	1975	sub recv {
		1976	unless ($_[0]{_ae_sent}) {
		1977	$WAITING
		1978	and Carp::croak "AnyEvent::CondVar: recursive blocking wait attempted";
		1979
		1980	local $WAITING = 1;
1768	$_[0]->_wait;	1981	$_[0]->_wait;
		1982	}
1769		1983
1770	Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak};	1984	$_[0]{_ae_croak}
1771	wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0]	1985	and Carp::croak $_[0]{_ae_croak};
		1986
		1987	wantarray
		1988	? @{ $_[0]{_ae_sent} }
		1989	: $_[0]{_ae_sent}[0]
1772	}	1990	}
1773		1991
1774	sub cb {	1992	sub cb {
1775	my $cv = shift;	1993	my $cv = shift;
1776		1994
…		…
1792	&{ $_[0]{_ae_end_cb} || sub { $_[0]->send } };	2010	&{ $_[0]{_ae_end_cb} || sub { $_[0]->send } };
1793	}	2011	}
1794		2012
1795	# undocumented/compatibility with pre-3.4	2013	# undocumented/compatibility with pre-3.4
1796	*broadcast = \&send;	2014	*broadcast = \&send;
1797	*wait = \&_wait;	2015	*wait = \&recv;
1798		2016
1799	=head1 ERROR AND EXCEPTION HANDLING	2017	=head1 ERROR AND EXCEPTION HANDLING
1800		2018
1801	In general, AnyEvent does not do any error handling - it relies on the	2019	In general, AnyEvent does not do any error handling - it relies on the
1802	caller to do that if required. The L<AnyEvent::Strict> module (see also	2020	caller to do that if required. The L<AnyEvent::Strict> module (see also
…		…
1814	$Event/EV::DIED->() >>, L<Glib> uses C<< install_exception_handler >> and	2032	$Event/EV::DIED->() >>, L<Glib> uses C<< install_exception_handler >> and
1815	so on.	2033	so on.
1816		2034
1817	=head1 ENVIRONMENT VARIABLES	2035	=head1 ENVIRONMENT VARIABLES
1818		2036
1819	The following environment variables are used by this module or its	2037	AnyEvent supports a number of environment variables that tune the
1820	submodules.	2038	runtime behaviour. They are usually evaluated when AnyEvent is
		2039	loaded, initialised, or a submodule that uses them is loaded. Many of
		2040	them also cause AnyEvent to load additional modules - for example,
		2041	C<PERL_ANYEVENT_DEBUG_WRAP> causes the L<AnyEvent::Debug> module to be
		2042	loaded.
1821		2043
1822	Note that AnyEvent will remove I<all> environment variables starting with	2044	All the environment variables documented here start with
1823	C<PERL_ANYEVENT_> from C<%ENV> when it is loaded while taint mode is	2045	C<PERL_ANYEVENT_>, which is what AnyEvent considers its own
1824	enabled.	2046	namespace. Other modules are encouraged (but by no means required) to use
		2047	C<PERL_ANYEVENT_SUBMODULE> if they have registered the AnyEvent::Submodule
		2048	namespace on CPAN, for any submodule. For example, L<AnyEvent::HTTP> could
		2049	be expected to use C<PERL_ANYEVENT_HTTP_PROXY> (it should not access env
		2050	variables starting with C<AE_>, see below).
		2051
		2052	All variables can also be set via the C<AE_> prefix, that is, instead
		2053	of setting C<PERL_ANYEVENT_VERBOSE> you can also set C<AE_VERBOSE>. In
		2054	case there is a clash btween anyevent and another program that uses
		2055	C<AE_something> you can set the corresponding C<PERL_ANYEVENT_something>
		2056	variable to the empty string, as those variables take precedence.
		2057
		2058	When AnyEvent is first loaded, it copies all C<AE_xxx> env variables
		2059	to their C<PERL_ANYEVENT_xxx> counterpart unless that variable already
		2060	exists. If taint mode is on, then AnyEvent will remove I<all> environment
		2061	variables starting with C<PERL_ANYEVENT_> from C<%ENV> (or replace them
		2062	with C<undef> or the empty string, if the corresaponding C<AE_> variable
		2063	is set).
		2064
		2065	The exact algorithm is currently:
		2066
		2067	1. if taint mode enabled, delete all PERL_ANYEVENT_xyz variables from %ENV
		2068	2. copy over AE_xyz to PERL_ANYEVENT_xyz unless the latter alraedy exists
		2069	3. if taint mode enabled, set all PERL_ANYEVENT_xyz variables to undef.
		2070
		2071	This ensures that child processes will not see the C<AE_> variables.
		2072
		2073	The following environment variables are currently known to AnyEvent:
1825		2074
1826	=over 4	2075	=over 4
1827		2076
1828	=item C<PERL_ANYEVENT_VERBOSE>	2077	=item C<PERL_ANYEVENT_VERBOSE>
1829		2078
1830	By default, AnyEvent will be completely silent except in fatal	2079	By default, AnyEvent will log messages with loglevel C<4> (C<error>) or
1831	conditions. You can set this environment variable to make AnyEvent more	2080	higher (see L<AnyEvent::Log>). You can set this environment variable to a
1832	talkative.	2081	numerical loglevel to make AnyEvent more (or less) talkative.
1833		2082
		2083	If you want to do more than just set the global logging level
		2084	you should have a look at C<PERL_ANYEVENT_LOG>, which allows much more
		2085	complex specifications.
		2086
		2087	When set to C<0> (C<off>), then no messages whatsoever will be logged with
		2088	everything else at defaults.
		2089
1834	When set to C<1> or higher, causes AnyEvent to warn about unexpected	2090	When set to C<5> or higher (C<warn>), AnyEvent warns about unexpected
1835	conditions, such as not being able to load the event model specified by	2091	conditions, such as not being able to load the event model specified by
1836	C<PERL_ANYEVENT_MODEL>.	2092	C<PERL_ANYEVENT_MODEL>, or a guard callback throwing an exception - this
		2093	is the minimum recommended level for use during development.
1837		2094
1838	When set to C<2> or higher, cause AnyEvent to report to STDERR which event	2095	When set to C<7> or higher (info), AnyEvent reports which event model it
1839	model it chooses.	2096	chooses.
1840		2097
1841	When set to C<8> or higher, then AnyEvent will report extra information on	2098	When set to C<8> or higher (debug), then AnyEvent will report extra
1842	which optional modules it loads and how it implements certain features.	2099	information on which optional modules it loads and how it implements
		2100	certain features.
		2101
		2102	=item C<PERL_ANYEVENT_LOG>
		2103
		2104	Accepts rather complex logging specifications. For example, you could log
		2105	all C<debug> messages of some module to stderr, warnings and above to
		2106	stderr, and errors and above to syslog, with:
		2107
		2108	PERL_ANYEVENT_LOG=Some::Module=debug,+log:filter=warn,+%syslog:%syslog=error,syslog
		2109
		2110	For the rather extensive details, see L<AnyEvent::Log>.
		2111
		2112	This variable is evaluated when AnyEvent (or L<AnyEvent::Log>) is loaded,
		2113	so will take effect even before AnyEvent has initialised itself.
		2114
		2115	Note that specifying this environment variable causes the L<AnyEvent::Log>
		2116	module to be loaded, while C<PERL_ANYEVENT_VERBOSE> does not, so only
		2117	using the latter saves a few hundred kB of memory unless a module
		2118	explicitly needs the extra features of AnyEvent::Log.
1843		2119
1844	=item C<PERL_ANYEVENT_STRICT>	2120	=item C<PERL_ANYEVENT_STRICT>
1845		2121
1846	AnyEvent does not do much argument checking by default, as thorough	2122	AnyEvent does not do much argument checking by default, as thorough
1847	argument checking is very costly. Setting this variable to a true value	2123	argument checking is very costly. Setting this variable to a true value
…		…
1849	check the arguments passed to most method calls. If it finds any problems,	2125	check the arguments passed to most method calls. If it finds any problems,
1850	it will croak.	2126	it will croak.
1851		2127
1852	In other words, enables "strict" mode.	2128	In other words, enables "strict" mode.
1853		2129
1854	Unlike C<use strict> (or it's modern cousin, C<< use L<common::sense>	2130	Unlike C<use strict> (or its modern cousin, C<< use L<common::sense>
1855	>>, it is definitely recommended to keep it off in production. Keeping	2131	>>, it is definitely recommended to keep it off in production. Keeping
1856	C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs	2132	C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs
1857	can be very useful, however.	2133	can be very useful, however.
1858		2134
		2135	=item C<PERL_ANYEVENT_DEBUG_SHELL>
		2136
		2137	If this env variable is nonempty, then its contents will be interpreted by
		2138	C<AnyEvent::Socket::parse_hostport> and C<AnyEvent::Debug::shell> (after
		2139	replacing every occurance of C<$$> by the process pid). The shell object
		2140	is saved in C<$AnyEvent::Debug::SHELL>.
		2141
		2142	This happens when the first watcher is created.
		2143
		2144	For example, to bind a debug shell on a unix domain socket in
		2145	F<< /tmp/debug<pid>.sock >>, you could use this:
		2146
		2147	PERL_ANYEVENT_DEBUG_SHELL=/tmp/debug\$\$.sock perlprog
		2148	# connect with e.g.: socat readline /tmp/debug123.sock
		2149
		2150	Or to bind to tcp port 4545 on localhost:
		2151
		2152	PERL_ANYEVENT_DEBUG_SHELL=127.0.0.1:4545 perlprog
		2153	# connect with e.g.: telnet localhost 4545
		2154
		2155	Note that creating sockets in F</tmp> or on localhost is very unsafe on
		2156	multiuser systems.
		2157
		2158	=item C<PERL_ANYEVENT_DEBUG_WRAP>
		2159
		2160	Can be set to C<0>, C<1> or C<2> and enables wrapping of all watchers for
		2161	debugging purposes. See C<AnyEvent::Debug::wrap> for details.
		2162
1859	=item C<PERL_ANYEVENT_MODEL>	2163	=item C<PERL_ANYEVENT_MODEL>
1860		2164
1861	This can be used to specify the event model to be used by AnyEvent, before	2165	This can be used to specify the event model to be used by AnyEvent, before
1862	auto detection and -probing kicks in. It must be a string consisting	2166	auto detection and -probing kicks in.
1863	entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended	2167
		2168	It normally is a string consisting entirely of ASCII letters (e.g. C<EV>
		2169	or C<IOAsync>). The string C<AnyEvent::Impl::> gets prepended and the
1864	and the resulting module name is loaded and if the load was successful,	2170	resulting module name is loaded and - if the load was successful - used as
1865	used as event model. If it fails to load AnyEvent will proceed with	2171	event model backend. If it fails to load then AnyEvent will proceed with
1866	auto detection and -probing.	2172	auto detection and -probing.
1867		2173
1868	This functionality might change in future versions.	2174	If the string ends with C<::> instead (e.g. C<AnyEvent::Impl::EV::>) then
		2175	nothing gets prepended and the module name is used as-is (hint: C<::> at
		2176	the end of a string designates a module name and quotes it appropriately).
1869		2177
1870	For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you	2178	For example, to force the pure perl model (L<AnyEvent::Loop::Perl>) you
1871	could start your program like this:	2179	could start your program like this:
1872		2180
1873	PERL_ANYEVENT_MODEL=Perl perl ...	2181	PERL_ANYEVENT_MODEL=Perl perl ...
		2182
		2183	=item C<PERL_ANYEVENT_IO_MODEL>
		2184
		2185	The current file I/O model - see L<AnyEvent::IO> for more info.
		2186
		2187	At the moment, only C<Perl> (small, pure-perl, synchronous) and
		2188	C<IOAIO> (truly asynchronous) are supported. The default is C<IOAIO> if
		2189	L<AnyEvent::AIO> can be loaded, otherwise it is C<Perl>.
1874		2190
1875	=item C<PERL_ANYEVENT_PROTOCOLS>	2191	=item C<PERL_ANYEVENT_PROTOCOLS>
1876		2192
1877	Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences	2193	Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences
1878	for IPv4 or IPv6. The default is unspecified (and might change, or be the result	2194	for IPv4 or IPv6. The default is unspecified (and might change, or be the result
…		…
1891	but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4>	2207	but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4>
1892	- only support IPv4, never try to resolve or contact IPv6	2208	- only support IPv4, never try to resolve or contact IPv6
1893	addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or	2209	addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or
1894	IPv6, but prefer IPv6 over IPv4.	2210	IPv6, but prefer IPv6 over IPv4.
1895		2211
		2212	=item C<PERL_ANYEVENT_HOSTS>
		2213
		2214	This variable, if specified, overrides the F</etc/hosts> file used by
		2215	L<AnyEvent::Socket>C<::resolve_sockaddr>, i.e. hosts aliases will be read
		2216	from that file instead.
		2217
1896	=item C<PERL_ANYEVENT_EDNS0>	2218	=item C<PERL_ANYEVENT_EDNS0>
1897		2219
1898	Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension	2220	Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension for
1899	for DNS. This extension is generally useful to reduce DNS traffic, but	2221	DNS. This extension is generally useful to reduce DNS traffic, especially
1900	some (broken) firewalls drop such DNS packets, which is why it is off by	2222	when DNSSEC is involved, but some (broken) firewalls drop such DNS
1901	default.	2223	packets, which is why it is off by default.
1902		2224
1903	Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce	2225	Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce
1904	EDNS0 in its DNS requests.	2226	EDNS0 in its DNS requests.
1905		2227
1906	=item C<PERL_ANYEVENT_MAX_FORKS>	2228	=item C<PERL_ANYEVENT_MAX_FORKS>
…		…
1912		2234
1913	The default value for the C<max_outstanding> parameter for the default DNS	2235	The default value for the C<max_outstanding> parameter for the default DNS
1914	resolver - this is the maximum number of parallel DNS requests that are	2236	resolver - this is the maximum number of parallel DNS requests that are
1915	sent to the DNS server.	2237	sent to the DNS server.
1916		2238
		2239	=item C<PERL_ANYEVENT_MAX_SIGNAL_LATENCY>
		2240
		2241	Perl has inherently racy signal handling (you can basically choose between
		2242	losing signals and memory corruption) - pure perl event loops (including
		2243	C<AnyEvent::Loop>, when C<Async::Interrupt> isn't available) therefore
		2244	have to poll regularly to avoid losing signals.
		2245
		2246	Some event loops are racy, but don't poll regularly, and some event loops
		2247	are written in C but are still racy. For those event loops, AnyEvent
		2248	installs a timer that regularly wakes up the event loop.
		2249
		2250	By default, the interval for this timer is C<10> seconds, but you can
		2251	override this delay with this environment variable (or by setting
		2252	the C<$AnyEvent::MAX_SIGNAL_LATENCY> variable before creating signal
		2253	watchers).
		2254
		2255	Lower values increase CPU (and energy) usage, higher values can introduce
		2256	long delays when reaping children or waiting for signals.
		2257
		2258	The L<AnyEvent::Async> module, if available, will be used to avoid this
		2259	polling (with most event loops).
		2260
1917	=item C<PERL_ANYEVENT_RESOLV_CONF>	2261	=item C<PERL_ANYEVENT_RESOLV_CONF>
1918		2262
1919	The file to use instead of F</etc/resolv.conf> (or OS-specific	2263	The absolute path to a F<resolv.conf>-style file to use instead of
1920	configuration) in the default resolver. When set to the empty string, no	2264	F</etc/resolv.conf> (or the OS-specific configuration) in the default
1921	default config will be used.	2265	resolver, or the empty string to select the default configuration.
1922		2266
1923	=item C<PERL_ANYEVENT_CA_FILE>, C<PERL_ANYEVENT_CA_PATH>.	2267	=item C<PERL_ANYEVENT_CA_FILE>, C<PERL_ANYEVENT_CA_PATH>.
1924		2268
1925	When neither C<ca_file> nor C<ca_path> was specified during	2269	When neither C<ca_file> nor C<ca_path> was specified during
1926	L<AnyEvent::TLS> context creation, and either of these environment	2270	L<AnyEvent::TLS> context creation, and either of these environment
1927	variables exist, they will be used to specify CA certificate locations	2271	variables are nonempty, they will be used to specify CA certificate
1928	instead of a system-dependent default.	2272	locations instead of a system-dependent default.
1929		2273
1930	=item C<PERL_ANYEVENT_AVOID_GUARD> and C<PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT>	2274	=item C<PERL_ANYEVENT_AVOID_GUARD> and C<PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT>
1931		2275
1932	When these are set to C<1>, then the respective modules are not	2276	When these are set to C<1>, then the respective modules are not
1933	loaded. Mostly good for testing AnyEvent itself.	2277	loaded. Mostly good for testing AnyEvent itself.
…		…
2265	(even when used without AnyEvent), but most event loops have acceptable	2609	(even when used without AnyEvent), but most event loops have acceptable
2266	performance with or without AnyEvent.	2610	performance with or without AnyEvent.
2267		2611
2268	=item * The overhead AnyEvent adds is usually much smaller than the overhead of	2612	=item * The overhead AnyEvent adds is usually much smaller than the overhead of
2269	the actual event loop, only with extremely fast event loops such as EV	2613	the actual event loop, only with extremely fast event loops such as EV
2270	adds AnyEvent significant overhead.	2614	does AnyEvent add significant overhead.
2271		2615
2272	=item * You should avoid POE like the plague if you want performance or	2616	=item * You should avoid POE like the plague if you want performance or
2273	reasonable memory usage.	2617	reasonable memory usage.
2274		2618
2275	=back	2619	=back
…		…
2505	unless defined $SIG{PIPE};	2849	unless defined $SIG{PIPE};
2506		2850
2507	=head1 RECOMMENDED/OPTIONAL MODULES	2851	=head1 RECOMMENDED/OPTIONAL MODULES
2508		2852
2509	One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and	2853	One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and
2510	it's built-in modules) are required to use it.	2854	its built-in modules) are required to use it.
2511		2855
2512	That does not mean that AnyEvent won't take advantage of some additional	2856	That does not mean that AnyEvent won't take advantage of some additional
2513	modules if they are installed.	2857	modules if they are installed.
2514		2858
2515	This section explains which additional modules will be used, and how they	2859	This section explains which additional modules will be used, and how they
…		…
2573	the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL.	2917	the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL.
2574		2918
2575	=item L<Time::HiRes>	2919	=item L<Time::HiRes>
2576		2920
2577	This module is part of perl since release 5.008. It will be used when the	2921	This module is part of perl since release 5.008. It will be used when the
2578	chosen event library does not come with a timing source on it's own. The	2922	chosen event library does not come with a timing source of its own. The
2579	pure-perl event loop (L<AnyEvent::Impl::Perl>) will additionally use it to	2923	pure-perl event loop (L<AnyEvent::Loop>) will additionally load it to
2580	try to use a monotonic clock for timing stability.	2924	try to use a monotonic clock for timing stability.
		2925
		2926	=item L<AnyEvent::AIO> (and L<IO::AIO>)
		2927
		2928	The default implementation of L<AnyEvent::IO> is to do I/O synchronously,
		2929	stopping programs while they access the disk, which is fine for a lot of
		2930	programs.
		2931
		2932	Installing AnyEvent::AIO (and its IO::AIO dependency) makes it switch to
		2933	a true asynchronous implementation, so event processing can continue even
		2934	while waiting for disk I/O.
2581		2935
2582	=back	2936	=back
2583		2937
2584		2938
2585	=head1 FORK	2939	=head1 FORK
…		…
2646	pronounced).	3000	pronounced).
2647		3001
2648		3002
2649	=head1 SEE ALSO	3003	=head1 SEE ALSO
2650		3004
2651	Utility functions: L<AnyEvent::Util>.	3005	Tutorial/Introduction: L<AnyEvent::Intro>.
2652		3006
2653	Event modules: L<EV>, L<EV::Glib>, L<Glib::EV>, L<Event>, L<Glib::Event>,	3007	FAQ: L<AnyEvent::FAQ>.
2654	L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.	3008
		3009	Utility functions: L<AnyEvent::Util> (misc. grab-bag), L<AnyEvent::Log>
		3010	(simply logging).
		3011
		3012	Development/Debugging: L<AnyEvent::Strict> (stricter checking),
		3013	L<AnyEvent::Debug> (interactive shell, watcher tracing).
		3014
		3015	Supported event modules: L<AnyEvent::Loop>, L<EV>, L<EV::Glib>,
		3016	L<Glib::EV>, L<Event>, L<Glib::Event>, L<Glib>, L<Tk>, L<Event::Lib>,
		3017	L<Qt>, L<POE>, L<FLTK>.
2655		3018
2656	Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,	3019	Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,
2657	L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,	3020	L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,
2658	L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,	3021	L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,
2659	L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>.	3022	L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>,
		3023	L<AnyEvent::Impl::FLTK>.
2660		3024
2661	Non-blocking file handles, sockets, TCP clients and	3025	Non-blocking handles, pipes, stream sockets, TCP clients and
2662	servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.	3026	servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.
2663		3027
		3028	Asynchronous File I/O: L<AnyEvent::IO>.
		3029
2664	Asynchronous DNS: L<AnyEvent::DNS>.	3030	Asynchronous DNS: L<AnyEvent::DNS>.
2665		3031
2666	Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>,	3032	Thread support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>.
2667	L<Coro::Event>,
2668		3033
2669	Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::XMPP>,	3034	Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::IRC>,
2670	L<AnyEvent::HTTP>.	3035	L<AnyEvent::HTTP>.
2671		3036
2672		3037
2673	=head1 AUTHOR	3038	=head1 AUTHOR
2674		3039
2675	Marc Lehmann <schmorp@schmorp.de>	3040	Marc Lehmann <schmorp@schmorp.de>
2676	http://home.schmorp.de/	3041	http://anyevent.schmorp.de
2677		3042
2678	=cut	3043	=cut
2679		3044
2680	1	3045	1
2681		3046

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