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

Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.28 by root, Sat Oct 27 15:10:09 2007 UTC vs.
Revision 1.71 by root, Fri Apr 25 07:29:42 2008 UTC

…		…
1	=head1 NAME	1	=head1 NAME
2		2
3	AnyEvent - provide framework for multiple event loops	3	AnyEvent - provide framework for multiple event loops
4		4
5	Event, Coro, Glib, Tk, Perl - various supported event loops	5	EV, Event, Coro::EV, Coro::Event, Glib, Tk, Perl, Event::Lib, Qt, POE - various supported event loops
6		6
7	=head1 SYNOPSIS	7	=head1 SYNOPSIS
8		8
9	use AnyEvent;	9	use AnyEvent;
10		10
14		14
15	my $w = AnyEvent->timer (after => $seconds, cb => sub {	15	my $w = AnyEvent->timer (after => $seconds, cb => sub {
16	...	16	...
17	});	17	});
18		18
19	my $w = AnyEvent->condvar; # stores wether a condition was flagged	19	my $w = AnyEvent->condvar; # stores whether a condition was flagged
20	$w->wait; # enters "main loop" till $condvar gets ->broadcast	20	$w->wait; # enters "main loop" till $condvar gets ->broadcast
21	$w->broadcast; # wake up current and all future wait's	21	$w->broadcast; # wake up current and all future wait's
		22
		23	=head1 WHY YOU SHOULD USE THIS MODULE (OR NOT)
		24
		25	Glib, POE, IO::Async, Event... CPAN offers event models by the dozen
		26	nowadays. So what is different about AnyEvent?
		27
		28	Executive Summary: AnyEvent is I<compatible>, AnyEvent is I<free of
		29	policy> and AnyEvent is I<small and efficient>.
		30
		31	First and foremost, I<AnyEvent is not an event model> itself, it only
		32	interfaces to whatever event model the main program happens to use in a
		33	pragmatic way. For event models and certain classes of immortals alike,
		34	the statement "there can only be one" is a bitter reality: In general,
		35	only one event loop can be active at the same time in a process. AnyEvent
		36	helps hiding the differences between those event loops.
		37
		38	The goal of AnyEvent is to offer module authors the ability to do event
		39	programming (waiting for I/O or timer events) without subscribing to a
		40	religion, a way of living, and most importantly: without forcing your
		41	module users into the same thing by forcing them to use the same event
		42	model you use.
		43
		44	For modules like POE or IO::Async (which is a total misnomer as it is
		45	actually doing all I/O I<synchronously>...), using them in your module is
		46	like joining a cult: After you joined, you are dependent on them and you
		47	cannot use anything else, as it is simply incompatible to everything that
		48	isn't itself. What's worse, all the potential users of your module are
		49	I<also> forced to use the same event loop you use.
		50
		51	AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works
		52	fine. AnyEvent + Tk works fine etc. etc. but none of these work together
		53	with the rest: POE + IO::Async? no go. Tk + Event? no go. Again: if
		54	your module uses one of those, every user of your module has to use it,
		55	too. But if your module uses AnyEvent, it works transparently with all
		56	event models it supports (including stuff like POE and IO::Async, as long
		57	as those use one of the supported event loops. It is trivial to add new
		58	event loops to AnyEvent, too, so it is future-proof).
		59
		60	In addition to being free of having to use I<the one and only true event
		61	model>, AnyEvent also is free of bloat and policy: with POE or similar
		62	modules, you get an enourmous amount of code and strict rules you have to
		63	follow. AnyEvent, on the other hand, is lean and up to the point, by only
		64	offering the functionality that is necessary, in as thin as a wrapper as
		65	technically possible.
		66
		67	Of course, if you want lots of policy (this can arguably be somewhat
		68	useful) and you want to force your users to use the one and only event
		69	model, you should I<not> use this module.
		70
22		71
23	=head1 DESCRIPTION	72	=head1 DESCRIPTION
24		73
25	L<AnyEvent> provides an identical interface to multiple event loops. This	74	L<AnyEvent> provides an identical interface to multiple event loops. This
26	allows module authors to utilise an event loop without forcing module	75	allows module authors to utilise an event loop without forcing module
27	users to use the same event loop (as only a single event loop can coexist	76	users to use the same event loop (as only a single event loop can coexist
28	peacefully at any one time).	77	peacefully at any one time).
29		78
30	The interface itself is vaguely similar but not identical to the Event	79	The interface itself is vaguely similar, but not identical to the L<Event>
31	module.	80	module.
32		81
33	On the first call of any method, the module tries to detect the currently	82	During the first call of any watcher-creation method, the module tries
34	loaded event loop by probing wether any of the following modules is	83	to detect the currently loaded event loop by probing whether one of the
35	loaded: L<Coro::Event>, L<Event>, L<Glib>, L<Tk>. The first one found is	84	following modules is already loaded: L<Coro::EV>, L<Coro::Event>, L<EV>,
36	used. If none is found, the module tries to load these modules in the	85	L<Event>, L<Glib>, L<Tk>, L<AnyEvent::Impl::Perl>, L<Event::Lib>, L<Qt>,
37	order given. The first one that could be successfully loaded will be	86	L<POE>. The first one found is used. If none are found, the module tries
38	used. If still none could be found, AnyEvent will fall back to a pure-perl	87	to load these modules (excluding Event::Lib, Qt and POE as the pure perl
39	event loop, which is also not very efficient.	88	adaptor should always succeed) in the order given. The first one that can
		89	be successfully loaded will be used. If, after this, still none could be
		90	found, AnyEvent will fall back to a pure-perl event loop, which is not
		91	very efficient, but should work everywhere.
40		92
41	Because AnyEvent first checks for modules that are already loaded, loading	93	Because AnyEvent first checks for modules that are already loaded, loading
42	an Event model explicitly before first using AnyEvent will likely make	94	an event model explicitly before first using AnyEvent will likely make
43	that model the default. For example:	95	that model the default. For example:
44		96
45	use Tk;	97	use Tk;
46	use AnyEvent;	98	use AnyEvent;
47		99
48	# .. AnyEvent will likely default to Tk	100	# .. AnyEvent will likely default to Tk
		101
		102	The I<likely> means that, if any module loads another event model and
		103	starts using it, all bets are off. Maybe you should tell their authors to
		104	use AnyEvent so their modules work together with others seamlessly...
49		105
50	The pure-perl implementation of AnyEvent is called	106	The pure-perl implementation of AnyEvent is called
51	C<AnyEvent::Impl::Perl>. Like other event modules you can load it	107	C<AnyEvent::Impl::Perl>. Like other event modules you can load it
52	explicitly.	108	explicitly.
53		109
…		…
56	AnyEvent has the central concept of a I<watcher>, which is an object that	112	AnyEvent has the central concept of a I<watcher>, which is an object that
57	stores relevant data for each kind of event you are waiting for, such as	113	stores relevant data for each kind of event you are waiting for, such as
58	the callback to call, the filehandle to watch, etc.	114	the callback to call, the filehandle to watch, etc.
59		115
60	These watchers are normal Perl objects with normal Perl lifetime. After	116	These watchers are normal Perl objects with normal Perl lifetime. After
61	creating a watcher it will immediately "watch" for events and invoke	117	creating a watcher it will immediately "watch" for events and invoke the
		118	callback when the event occurs (of course, only when the event model
		119	is in control).
		120
62	the callback. To disable the watcher you have to destroy it (e.g. by	121	To disable the watcher you have to destroy it (e.g. by setting the
63	setting the variable that stores it to C<undef> or otherwise deleting all	122	variable you store it in to C<undef> or otherwise deleting all references
64	references to it).	123	to it).
65		124
66	All watchers are created by calling a method on the C<AnyEvent> class.	125	All watchers are created by calling a method on the C<AnyEvent> class.
67		126
		127	Many watchers either are used with "recursion" (repeating timers for
		128	example), or need to refer to their watcher object in other ways.
		129
		130	An any way to achieve that is this pattern:
		131
		132	my $w; $w = AnyEvent->type (arg => value ..., cb => sub {
		133	# you can use $w here, for example to undef it
		134	undef $w;
		135	});
		136
		137	Note that C<my $w; $w => combination. This is necessary because in Perl,
		138	my variables are only visible after the statement in which they are
		139	declared.
		140
68	=head2 IO WATCHERS	141	=head2 IO WATCHERS
69		142
70	You can create I/O watcher by calling the C<< AnyEvent->io >> method with	143	You can create an I/O watcher by calling the C<< AnyEvent->io >> method
71	the following mandatory arguments:	144	with the following mandatory key-value pairs as arguments:
72		145
73	C<fh> the Perl I<filehandle> (not filedescriptor) to watch for	146	C<fh> the Perl I<file handle> (I<not> file descriptor) to watch for
74	events. C<poll> must be a string that is either C<r> or C<w>, that creates	147	events. C<poll> must be a string that is either C<r> or C<w>, which
75	a watcher waiting for "r"eadable or "w"ritable events. C<cb> teh callback	148	creates a watcher waiting for "r"eadable or "w"ritable events,
76	to invoke everytime the filehandle becomes ready.	149	respectively. C<cb> is the callback to invoke each time the file handle
		150	becomes ready.
77		151
78	Only one io watcher per C<fh> and C<poll> combination is allowed (i.e. on	152	As long as the I/O watcher exists it will keep the file descriptor or a
79	a socket you can have one r + one w, not any more (limitation comes from	153	copy of it alive/open.
80	Tk - if you are sure you are not using Tk this limitation is gone).
81		154
82	Filehandles will be kept alive, so as long as the watcher exists, the	155	It is not allowed to close a file handle as long as any watcher is active
83	filehandle exists, too.	156	on the underlying file descriptor.
		157
		158	Some event loops issue spurious readyness notifications, so you should
		159	always use non-blocking calls when reading/writing from/to your file
		160	handles.
84		161
85	Example:	162	Example:
86		163
87	# wait for readability of STDIN, then read a line and disable the watcher	164	# wait for readability of STDIN, then read a line and disable the watcher
88	my $w; $w = AnyEvent->io (fh => \*STDIN, poll => 'r', cb => sub {	165	my $w; $w = AnyEvent->io (fh => \*STDIN, poll => 'r', cb => sub {
…		…
94	=head2 TIME WATCHERS	171	=head2 TIME WATCHERS
95		172
96	You can create a time watcher by calling the C<< AnyEvent->timer >>	173	You can create a time watcher by calling the C<< AnyEvent->timer >>
97	method with the following mandatory arguments:	174	method with the following mandatory arguments:
98		175
99	C<after> after how many seconds (fractions are supported) should the timer	176	C<after> specifies after how many seconds (fractional values are
100	activate. C<cb> the callback to invoke.	177	supported) should the timer activate. C<cb> the callback to invoke in that
		178	case.
101		179
102	The timer callback will be invoked at most once: if you want a repeating	180	The timer callback will be invoked at most once: if you want a repeating
103	timer you have to create a new watcher (this is a limitation by both Tk	181	timer you have to create a new watcher (this is a limitation by both Tk
104	and Glib).	182	and Glib).
105		183
…		…
109	my $w = AnyEvent->timer (after => 7.7, cb => sub {	187	my $w = AnyEvent->timer (after => 7.7, cb => sub {
110	warn "timeout\n";	188	warn "timeout\n";
111	});	189	});
112		190
113	# to cancel the timer:	191	# to cancel the timer:
114	undef $w	192	undef $w;
115		193
		194	Example 2:
		195
		196	# fire an event after 0.5 seconds, then roughly every second
		197	my $w;
		198
		199	my $cb = sub {
		200	# cancel the old timer while creating a new one
		201	$w = AnyEvent->timer (after => 1, cb => $cb);
		202	};
		203
		204	# start the "loop" by creating the first watcher
		205	$w = AnyEvent->timer (after => 0.5, cb => $cb);
		206
		207	=head3 TIMING ISSUES
		208
		209	There are two ways to handle timers: based on real time (relative, "fire
		210	in 10 seconds") and based on wallclock time (absolute, "fire at 12
		211	o'clock").
		212
		213	While most event loops expect timers to specified in a relative way, they
		214	use absolute time internally. This makes a difference when your clock
		215	"jumps", for example, when ntp decides to set your clock backwards from
		216	the wrong date of 2014-01-01 to 2008-01-01, a watcher that is supposed to
		217	fire "after" a second might actually take six years to finally fire.
		218
		219	AnyEvent cannot compensate for this. The only event loop that is conscious
		220	about these issues is L<EV>, which offers both relative (ev_timer, based
		221	on true relative time) and absolute (ev_periodic, based on wallclock time)
		222	timers.
		223
		224	AnyEvent always prefers relative timers, if available, matching the
		225	AnyEvent API.
		226
		227	=head2 SIGNAL WATCHERS
		228
		229	You can watch for signals using a signal watcher, C<signal> is the signal
		230	I<name> without any C<SIG> prefix, C<cb> is the Perl callback to
		231	be invoked whenever a signal occurs.
		232
		233	Multiple signal occurances can be clumped together into one callback
		234	invocation, and callback invocation will be synchronous. synchronous means
		235	that it might take a while until the signal gets handled by the process,
		236	but it is guarenteed not to interrupt any other callbacks.
		237
		238	The main advantage of using these watchers is that you can share a signal
		239	between multiple watchers.
		240
		241	This watcher might use C<%SIG>, so programs overwriting those signals
		242	directly will likely not work correctly.
		243
		244	Example: exit on SIGINT
		245
		246	my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
		247
		248	=head2 CHILD PROCESS WATCHERS
		249
		250	You can also watch on a child process exit and catch its exit status.
		251
		252	The child process is specified by the C<pid> argument (if set to C<0>, it
		253	watches for any child process exit). The watcher will trigger as often
		254	as status change for the child are received. This works by installing a
		255	signal handler for C<SIGCHLD>. The callback will be called with the pid
		256	and exit status (as returned by waitpid).
		257
		258	Example: wait for pid 1333
		259
		260	my $w = AnyEvent->child (
		261	pid => 1333,
		262	cb => sub {
		263	my ($pid, $status) = @_;
		264	warn "pid $pid exited with status $status";
		265	},
		266	);
		267
116	=head2 CONDITION WATCHERS	268	=head2 CONDITION VARIABLES
117		269
118	Condition watchers can be created by calling the C<< AnyEvent->condvar >>	270	Condition variables can be created by calling the C<< AnyEvent->condvar >>
119	method without any arguments.	271	method without any arguments.
120		272
121	A condition watcher watches for a condition - precisely that the C<<	273	A condition variable waits for a condition - precisely that the C<<
122	->broadcast >> method has been called.	274	->broadcast >> method has been called.
123		275
124	The watcher has only two methods:	276	They are very useful to signal that a condition has been fulfilled, for
		277	example, if you write a module that does asynchronous http requests,
		278	then a condition variable would be the ideal candidate to signal the
		279	availability of results.
		280
		281	You can also use condition variables to block your main program until
		282	an event occurs - for example, you could C<< ->wait >> in your main
		283	program until the user clicks the Quit button in your app, which would C<<
		284	->broadcast >> the "quit" event.
		285
		286	Note that condition variables recurse into the event loop - if you have
		287	two pirces of code that call C<< ->wait >> in a round-robbin fashion, you
		288	lose. Therefore, condition variables are good to export to your caller, but
		289	you should avoid making a blocking wait yourself, at least in callbacks,
		290	as this asks for trouble.
		291
		292	This object has two methods:
125		293
126	=over 4	294	=over 4
127		295
128	=item $cv->wait	296	=item $cv->wait
129		297
130	Wait (blocking if necessary) until the C<< ->broadcast >> method has been	298	Wait (blocking if necessary) until the C<< ->broadcast >> method has been
131	called on c<$cv>, while servicing other watchers normally.	299	called on c<$cv>, while servicing other watchers normally.
132		300
133	Not all event models support a blocking wait - some die in that case, so
134	if you are using this from a module, never require a blocking wait, but
135	let the caller decide wether the call will block or not (for example,
136	by coupling condition variables with some kind of request results and
137	supporting callbacks so the caller knows that getting the result will not
138	block, while still suppporting blockign waits if the caller so desires).
139
140	You can only wait once on a condition - additional calls will return	301	You can only wait once on a condition - additional calls will return
141	immediately.	302	immediately.
142		303
		304	Not all event models support a blocking wait - some die in that case
		305	(programs might want to do that to stay interactive), so I<if you are
		306	using this from a module, never require a blocking wait>, but let the
		307	caller decide whether the call will block or not (for example, by coupling
		308	condition variables with some kind of request results and supporting
		309	callbacks so the caller knows that getting the result will not block,
		310	while still suppporting blocking waits if the caller so desires).
		311
		312	Another reason I<never> to C<< ->wait >> in a module is that you cannot
		313	sensibly have two C<< ->wait >>'s in parallel, as that would require
		314	multiple interpreters or coroutines/threads, none of which C<AnyEvent>
		315	can supply (the coroutine-aware backends L<AnyEvent::Impl::CoroEV> and
		316	L<AnyEvent::Impl::CoroEvent> explicitly support concurrent C<< ->wait >>'s
		317	from different coroutines, however).
		318
143	=item $cv->broadcast	319	=item $cv->broadcast
144		320
145	Flag the condition as ready - a running C<< ->wait >> and all further	321	Flag the condition as ready - a running C<< ->wait >> and all further
146	calls to C<wait> will return after this method has been called. If nobody	322	calls to C<wait> will (eventually) return after this method has been
147	is waiting the broadcast will be remembered..	323	called. If nobody is waiting the broadcast will be remembered..
		324
		325	=back
148		326
149	Example:	327	Example:
150		328
151	# wait till the result is ready	329	# wait till the result is ready
152	my $result_ready = AnyEvent->condvar;	330	my $result_ready = AnyEvent->condvar;
153		331
154	# do something such as adding a timer	332	# do something such as adding a timer
155	# or socket watcher the calls $result_ready->broadcast	333	# or socket watcher the calls $result_ready->broadcast
156	# when the "result" is ready.	334	# when the "result" is ready.
		335	# in this case, we simply use a timer:
		336	my $w = AnyEvent->timer (
		337	after => 1,
		338	cb => sub { $result_ready->broadcast },
		339	);
157		340
		341	# this "blocks" (while handling events) till the watcher
		342	# calls broadcast
158	$result_ready->wait;	343	$result_ready->wait;
159		344
160	=back	345	=head1 GLOBAL VARIABLES AND FUNCTIONS
161
162	=head2 SIGNAL WATCHERS
163
164	You can listen for signals using a signal watcher, C<signal> is the signal
165	I<name> without any C<SIG> prefix. Multiple signals events can be clumped
166	together into one callback invocation, and callback invocation might or
167	might not be asynchronous.
168
169	These watchers might use C<%SIG>, so programs overwriting those signals
170	directly will likely not work correctly.
171
172	Example: exit on SIGINT
173
174	my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
175
176	=head2 CHILD PROCESS WATCHERS
177
178	You can also listen for the status of a child process specified by the
179	C<pid> argument. The watcher will only trigger once. This works by
180	installing a signal handler for C<SIGCHLD>.
181
182	Example: wait for pid 1333
183
184	my $w = AnyEvent->child (pid => 1333, cb => sub { warn "exit status $?" });
185
186	=head1 GLOBALS
187		346
188	=over 4	347	=over 4
189		348
190	=item $AnyEvent::MODEL	349	=item $AnyEvent::MODEL
191		350
…		…
195	C<AnyEvent::Impl:xxx> modules, but can be any other class in the case	354	C<AnyEvent::Impl:xxx> modules, but can be any other class in the case
196	AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode>).	355	AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode>).
197		356
198	The known classes so far are:	357	The known classes so far are:
199		358
200	AnyEvent::Impl::Coro based on Coro::Event, best choice.	359	AnyEvent::Impl::CoroEV based on Coro::EV, best choice.
		360	AnyEvent::Impl::CoroEvent based on Coro::Event, second best choice.
201	EV::AnyEvent based on EV (an interface to libevent)	361	AnyEvent::Impl::EV based on EV (an interface to libev, best choice).
202	AnyEvent::Impl::Event based on Event, also best choice :)	362	AnyEvent::Impl::Event based on Event, second best choice.
203	AnyEvent::Impl::Glib based on Glib, second-best choice.	363	AnyEvent::Impl::Glib based on Glib, third-best choice.
204	AnyEvent::Impl::Tk based on Tk, very bad choice.	364	AnyEvent::Impl::Tk based on Tk, very bad choice.
205	AnyEvent::Impl::Perl pure-perl implementation, inefficient.	365	AnyEvent::Impl::Perl pure-perl implementation, inefficient but portable.
		366	AnyEvent::Impl::Qt based on Qt, cannot be autoprobed (see its docs).
		367	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
		368	AnyEvent::Impl::POE based on POE, not generic enough for full support.
		369
		370	There is no support for WxWidgets, as WxWidgets has no support for
		371	watching file handles. However, you can use WxWidgets through the
		372	POE Adaptor, as POE has a Wx backend that simply polls 20 times per
		373	second, which was considered to be too horrible to even consider for
		374	AnyEvent. Likewise, other POE backends can be used by AnyEvent by using
		375	it's adaptor.
		376
		377	AnyEvent knows about L<Prima> and L<Wx> and will try to use L<POE> when
		378	autodetecting them.
206		379
207	=item AnyEvent::detect	380	=item AnyEvent::detect
208		381
209	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model if	382	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model
210	necessary. You should only call this function right before you would have	383	if necessary. You should only call this function right before you would
211	created an AnyEvent watcher anyway, that is, very late at runtime.	384	have created an AnyEvent watcher anyway, that is, as late as possible at
		385	runtime.
212		386
213	=back	387	=back
214		388
215	=head1 WHAT TO DO IN A MODULE	389	=head1 WHAT TO DO IN A MODULE
216		390
217	As a module author, you should "use AnyEvent" and call AnyEvent methods	391	As a module author, you should C<use AnyEvent> and call AnyEvent methods
218	freely, but you should not load a specific event module or rely on it.	392	freely, but you should not load a specific event module or rely on it.
219		393
220	Be careful when you create watchers in the module body - Anyevent will	394	Be careful when you create watchers in the module body - AnyEvent will
221	decide which event module to use as soon as the first method is called, so	395	decide which event module to use as soon as the first method is called, so
222	by calling AnyEvent in your module body you force the user of your module	396	by calling AnyEvent in your module body you force the user of your module
223	to load the event module first.	397	to load the event module first.
224		398
		399	Never call C<< ->wait >> on a condition variable unless you I<know> that
		400	the C<< ->broadcast >> method has been called on it already. This is
		401	because it will stall the whole program, and the whole point of using
		402	events is to stay interactive.
		403
		404	It is fine, however, to call C<< ->wait >> when the user of your module
		405	requests it (i.e. if you create a http request object ad have a method
		406	called C<results> that returns the results, it should call C<< ->wait >>
		407	freely, as the user of your module knows what she is doing. always).
		408
225	=head1 WHAT TO DO IN THE MAIN PROGRAM	409	=head1 WHAT TO DO IN THE MAIN PROGRAM
226		410
227	There will always be a single main program - the only place that should	411	There will always be a single main program - the only place that should
228	dictate which event model to use.	412	dictate which event model to use.
229		413
230	If it doesn't care, it can just "use AnyEvent" and use it itself, or not	414	If it doesn't care, it can just "use AnyEvent" and use it itself, or not
231	do anything special and let AnyEvent decide which implementation to chose.	415	do anything special (it does not need to be event-based) and let AnyEvent
		416	decide which implementation to chose if some module relies on it.
232		417
233	If the main program relies on a specific event model (for example, in Gtk2	418	If the main program relies on a specific event model. For example, in
234	programs you have to rely on either Glib or Glib::Event), you should load	419	Gtk2 programs you have to rely on the Glib module. You should load the
235	it before loading AnyEvent or any module that uses it, generally, as early	420	event module before loading AnyEvent or any module that uses it: generally
236	as possible. The reason is that modules might create watchers when they	421	speaking, you should load it as early as possible. The reason is that
237	are loaded, and AnyEvent will decide on the event model to use as soon as	422	modules might create watchers when they are loaded, and AnyEvent will
238	it creates watchers, and it might chose the wrong one unless you load the	423	decide on the event model to use as soon as it creates watchers, and it
239	correct one yourself.	424	might chose the wrong one unless you load the correct one yourself.
240		425
241	You can chose to use a rather inefficient pure-perl implementation by	426	You can chose to use a rather inefficient pure-perl implementation by
242	loading the C<AnyEvent::Impl::Perl> module, but letting AnyEvent chose is	427	loading the C<AnyEvent::Impl::Perl> module, which gives you similar
243	generally better.	428	behaviour everywhere, but letting AnyEvent chose is generally better.
244		429
245	=cut	430	=cut
246		431
247	package AnyEvent;	432	package AnyEvent;
248		433
249	no warnings;	434	no warnings;
250	use strict;	435	use strict;
251		436
252	use Carp;	437	use Carp;
253		438
254	our $VERSION = '2.55';	439	our $VERSION = '3.3';
255	our $MODEL;	440	our $MODEL;
256		441
257	our $AUTOLOAD;	442	our $AUTOLOAD;
258	our @ISA;	443	our @ISA;
259		444
260	our $verbose = $ENV{PERL_ANYEVENT_VERBOSE}*1;	445	our $verbose = $ENV{PERL_ANYEVENT_VERBOSE}*1;
261		446
262	our @REGISTRY;	447	our @REGISTRY;
263		448
264	my @models = (	449	my @models = (
		450	[Coro::EV:: => AnyEvent::Impl::CoroEV::],
265	[Coro::Event:: => AnyEvent::Impl::Coro::],	451	[Coro::Event:: => AnyEvent::Impl::CoroEvent::],
266	[EV:: => EV::AnyEvent::],	452	[EV:: => AnyEvent::Impl::EV::],
267	[Event:: => AnyEvent::Impl::Event::],	453	[Event:: => AnyEvent::Impl::Event::],
268	[Glib:: => AnyEvent::Impl::Glib::],	454	[Glib:: => AnyEvent::Impl::Glib::],
269	[Tk:: => AnyEvent::Impl::Tk::],	455	[Tk:: => AnyEvent::Impl::Tk::],
		456	[Wx:: => AnyEvent::Impl::POE::],
		457	[Prima:: => AnyEvent::Impl::POE::],
270	[AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::],	458	[AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::],
		459	# everything below here will not be autoprobed as the pureperl backend should work everywhere
		460	[Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
		461	[Qt:: => AnyEvent::Impl::Qt::], # requires special main program
		462	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
271	);	463	);
272		464
273	our %method = map +($_ => 1), qw(io timer condvar broadcast wait signal one_event DESTROY);	465	our %method = map +($_ => 1), qw(io timer signal child condvar broadcast wait one_event DESTROY);
274		466
275	sub detect() {	467	sub detect() {
276	unless ($MODEL) {	468	unless ($MODEL) {
277	no strict 'refs';	469	no strict 'refs';
278		470
		471	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {
		472	my $model = "AnyEvent::Impl::$1";
		473	if (eval "require $model") {
		474	$MODEL = $model;
		475	warn "AnyEvent: loaded model '$model' (forced by \$PERL_ANYEVENT_MODEL), using it.\n" if $verbose > 1;
		476	} else {
		477	warn "AnyEvent: unable to load model '$model' (from \$PERL_ANYEVENT_MODEL):\n$@" if $verbose;
		478	}
		479	}
		480
279	# check for already loaded models	481	# check for already loaded models
		482	unless ($MODEL) {
280	for (@REGISTRY, @models) {	483	for (@REGISTRY, @models) {
281	my ($package, $model) = @$_;	484	my ($package, $model) = @$_;
282	if (${"$package\::VERSION"} > 0) {	485	if (${"$package\::VERSION"} > 0) {
283	if (eval "require $model") {	486	if (eval "require $model") {
284	$MODEL = $model;	487	$MODEL = $model;
285	warn "AnyEvent: found model '$model', using it.\n" if $verbose > 1;	488	warn "AnyEvent: autodetected model '$model', using it.\n" if $verbose > 1;
286	last;	489	last;
		490	}
287	}	491	}
288	}	492	}
289	}
290		493
291	unless ($MODEL) {	494	unless ($MODEL) {
292	# try to load a model	495	# try to load a model
293		496
294	for (@REGISTRY, @models) {	497	for (@REGISTRY, @models) {
295	my ($package, $model) = @$_;	498	my ($package, $model) = @$_;
296	if (eval "require $package"	499	if (eval "require $package"
297	and ${"$package\::VERSION"} > 0	500	and ${"$package\::VERSION"} > 0
298	and eval "require $model") {	501	and eval "require $model") {
299	$MODEL = $model;	502	$MODEL = $model;
300	warn "AnyEvent: autoprobed and loaded model '$model', using it.\n" if $verbose > 1;	503	warn "AnyEvent: autoprobed model '$model', using it.\n" if $verbose > 1;
301	last;	504	last;
		505	}
302	}	506	}
		507
		508	$MODEL
		509	or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV (or Coro+EV), Event (or Coro+Event) or Glib.";
303	}	510	}
304
305	$MODEL
306	or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: Event (or Coro+Event), Glib or Tk.";
307	}	511	}
308		512
309	unshift @ISA, $MODEL;	513	unshift @ISA, $MODEL;
310	push @{"$MODEL\::ISA"}, "AnyEvent::Base";	514	push @{"$MODEL\::ISA"}, "AnyEvent::Base";
311	}	515	}
…		…
369		573
370	# default implementation for ->child	574	# default implementation for ->child
371		575
372	our %PID_CB;	576	our %PID_CB;
373	our $CHLD_W;	577	our $CHLD_W;
		578	our $CHLD_DELAY_W;
374	our $PID_IDLE;	579	our $PID_IDLE;
375	our $WNOHANG;	580	our $WNOHANG;
376		581
377	sub _child_wait {	582	sub _child_wait {
378	while (0 < (my $pid = waitpid -1, $WNOHANG)) {	583	while (0 < (my $pid = waitpid -1, $WNOHANG)) {
379	$_->() for values %{ (delete $PID_CB{$pid}) \|\| {} };	584	$_->($pid, $?) for (values %{ $PID_CB{$pid} \|\| {} }),
		585	(values %{ $PID_CB{0} \|\| {} });
380	}	586	}
381		587
382	undef $PID_IDLE;	588	undef $PID_IDLE;
383	}	589	}
384		590
		591	sub _sigchld {
		592	# make sure we deliver these changes "synchronous" with the event loop.
		593	$CHLD_DELAY_W \|\|= AnyEvent->timer (after => 0, cb => sub {
		594	undef $CHLD_DELAY_W;
		595	&_child_wait;
		596	});
		597	}
		598
385	sub child {	599	sub child {
386	my (undef, %arg) = @_;	600	my (undef, %arg) = @_;
387		601
388	my $pid = uc $arg{pid}	602	defined (my $pid = $arg{pid} + 0)
389	or Carp::croak "required option 'pid' is missing";	603	or Carp::croak "required option 'pid' is missing";
390		604
391	$PID_CB{$pid}{$arg{cb}} = $arg{cb};	605	$PID_CB{$pid}{$arg{cb}} = $arg{cb};
392		606
393	unless ($WNOHANG) {	607	unless ($WNOHANG) {
394	$WNOHANG = eval { require POSIX; &POSIX::WNOHANG } \|\| 1;	608	$WNOHANG = eval { require POSIX; &POSIX::WNOHANG } \|\| 1;
395	}	609	}
396		610
397	unless ($CHLD_W) {	611	unless ($CHLD_W) {
398	$CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_child_wait);	612	$CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld);
399	# child could be a zombie already	613	# child could be a zombie already, so make at least one round
400	$PID_IDLE \|\|= AnyEvent->timer (after => 0, cb => \&_child_wait);	614	&_sigchld;
401	}	615	}
402		616
403	bless [$pid, $arg{cb}], "AnyEvent::Base::Child"	617	bless [$pid, $arg{cb}], "AnyEvent::Base::Child"
404	}	618	}
405		619
…		…
411		625
412	undef $CHLD_W unless keys %PID_CB;	626	undef $CHLD_W unless keys %PID_CB;
413	}	627	}
414		628
415	=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE	629	=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE
		630
		631	This is an advanced topic that you do not normally need to use AnyEvent in
		632	a module. This section is only of use to event loop authors who want to
		633	provide AnyEvent compatibility.
416		634
417	If you need to support another event library which isn't directly	635	If you need to support another event library which isn't directly
418	supported by AnyEvent, you can supply your own interface to it by	636	supported by AnyEvent, you can supply your own interface to it by
419	pushing, before the first watcher gets created, the package name of	637	pushing, before the first watcher gets created, the package name of
420	the event module and the package name of the interface to use onto	638	the event module and the package name of the interface to use onto
421	C<@AnyEvent::REGISTRY>. You can do that before and even without loading	639	C<@AnyEvent::REGISTRY>. You can do that before and even without loading
422	AnyEvent.	640	AnyEvent, so it is reasonably cheap.
423		641
424	Example:	642	Example:
425		643
426	push @AnyEvent::REGISTRY, [urxvt => urxvt::anyevent::];	644	push @AnyEvent::REGISTRY, [urxvt => urxvt::anyevent::];
427		645
428	This tells AnyEvent to (literally) use the C<urxvt::anyevent::>	646	This tells AnyEvent to (literally) use the C<urxvt::anyevent::>
429	package/class when it finds the C<urxvt> package/module is loaded. When	647	package/class when it finds the C<urxvt> package/module is already loaded.
		648
430	AnyEvent is loaded and asked to find a suitable event model, it will	649	When AnyEvent is loaded and asked to find a suitable event model, it
431	first check for the presence of urxvt.	650	will first check for the presence of urxvt by trying to C<use> the
		651	C<urxvt::anyevent> module.
432		652
433	The class should provide implementations for all watcher types (see	653	The class should provide implementations for all watcher types. See
434	L<AnyEvent::Impl::Event> (source code), L<AnyEvent::Impl::Glib>	654	L<AnyEvent::Impl::EV> (source code), L<AnyEvent::Impl::Glib> (Source code)
435	(Source code) and so on for actual examples, use C<perldoc -m	655	and so on for actual examples. Use C<perldoc -m AnyEvent::Impl::Glib> to
436	AnyEvent::Impl::Glib> to see the sources).	656	see the sources.
437		657
		658	If you don't provide C<signal> and C<child> watchers than AnyEvent will
		659	provide suitable (hopefully) replacements.
		660
438	The above isn't fictitious, the I<rxvt-unicode> (a.k.a. urxvt)	661	The above example isn't fictitious, the I<rxvt-unicode> (a.k.a. urxvt)
439	uses the above line as-is. An interface isn't included in AnyEvent	662	terminal emulator uses the above line as-is. An interface isn't included
440	because it doesn't make sense outside the embedded interpreter inside	663	in AnyEvent because it doesn't make sense outside the embedded interpreter
441	I<rxvt-unicode>, and it is updated and maintained as part of the	664	inside I<rxvt-unicode>, and it is updated and maintained as part of the
442	I<rxvt-unicode> distribution.	665	I<rxvt-unicode> distribution.
443		666
444	I<rxvt-unicode> also cheats a bit by not providing blocking access to	667	I<rxvt-unicode> also cheats a bit by not providing blocking access to
445	condition variables: code blocking while waiting for a condition will	668	condition variables: code blocking while waiting for a condition will
446	C<die>. This still works with most modules/usages, and blocking calls must	669	C<die>. This still works with most modules/usages, and blocking calls must
447	not be in an interactive application, so it makes sense.	670	not be done in an interactive application, so it makes sense.
448		671
449	=head1 ENVIRONMENT VARIABLES	672	=head1 ENVIRONMENT VARIABLES
450		673
451	The following environment variables are used by this module:	674	The following environment variables are used by this module:
452		675
453	C<PERL_ANYEVENT_VERBOSE> when set to C<2> or higher, reports which event	676	=over 4
454	model gets used.
455		677
		678	=item C<PERL_ANYEVENT_VERBOSE>
		679
		680	By default, AnyEvent will be completely silent except in fatal
		681	conditions. You can set this environment variable to make AnyEvent more
		682	talkative.
		683
		684	When set to C<1> or higher, causes AnyEvent to warn about unexpected
		685	conditions, such as not being able to load the event model specified by
		686	C<PERL_ANYEVENT_MODEL>.
		687
		688	When set to C<2> or higher, cause AnyEvent to report to STDERR which event
		689	model it chooses.
		690
		691	=item C<PERL_ANYEVENT_MODEL>
		692
		693	This can be used to specify the event model to be used by AnyEvent, before
		694	autodetection and -probing kicks in. It must be a string consisting
		695	entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended
		696	and the resulting module name is loaded and if the load was successful,
		697	used as event model. If it fails to load AnyEvent will proceed with
		698	autodetection and -probing.
		699
		700	This functionality might change in future versions.
		701
		702	For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you
		703	could start your program like this:
		704
		705	PERL_ANYEVENT_MODEL=Perl perl ...
		706
		707	=back
		708
456	=head1 EXAMPLE	709	=head1 EXAMPLE PROGRAM
457		710
458	The following program uses an io watcher to read data from stdin, a timer	711	The following program uses an IO watcher to read data from STDIN, a timer
459	to display a message once per second, and a condvar to exit the program	712	to display a message once per second, and a condition variable to quit the
460	when the user enters quit:	713	program when the user enters quit:
461		714
462	use AnyEvent;	715	use AnyEvent;
463		716
464	my $cv = AnyEvent->condvar;	717	my $cv = AnyEvent->condvar;
465		718
466	my $io_watcher = AnyEvent->io (fh => \*STDIN, poll => 'r', cb => sub {	719	my $io_watcher = AnyEvent->io (
		720	fh => \*STDIN,
		721	poll => 'r',
		722	cb => sub {
467	warn "io event <$_[0]>\n"; # will always output <r>	723	warn "io event <$_[0]>\n"; # will always output <r>
468	chomp (my $input = <STDIN>); # read a line	724	chomp (my $input = <STDIN>); # read a line
469	warn "read: $input\n"; # output what has been read	725	warn "read: $input\n"; # output what has been read
470	$cv->broadcast if $input =~ /^q/i; # quit program if /^q/i	726	$cv->broadcast if $input =~ /^q/i; # quit program if /^q/i
		727	},
471	});	728	);
472		729
473	my $time_watcher; # can only be used once	730	my $time_watcher; # can only be used once
474		731
475	sub new_timer {	732	sub new_timer {
476	$timer = AnyEvent->timer (after => 1, cb => sub {	733	$timer = AnyEvent->timer (after => 1, cb => sub {
…		…
558	$txn->{finished}->wait;	815	$txn->{finished}->wait;
559	return $txn->{result};	816	return $txn->{result};
560		817
561	The actual code goes further and collects all errors (C<die>s, exceptions)	818	The actual code goes further and collects all errors (C<die>s, exceptions)
562	that occured during request processing. The C<result> method detects	819	that occured during request processing. The C<result> method detects
563	wether an exception as thrown (it is stored inside the $txn object)	820	whether an exception as thrown (it is stored inside the $txn object)
564	and just throws the exception, which means connection errors and other	821	and just throws the exception, which means connection errors and other
565	problems get reported tot he code that tries to use the result, not in a	822	problems get reported tot he code that tries to use the result, not in a
566	random callback.	823	random callback.
567		824
568	All of this enables the following usage styles:	825	All of this enables the following usage styles:
569		826
570	1. Blocking:	827	1. Blocking:
571		828
572	my $data = $fcp->client_get ($url);	829	my $data = $fcp->client_get ($url);
573		830
574	2. Blocking, but parallelizing:	831	2. Blocking, but running in parallel:
575		832
576	my @datas = map $_->result,	833	my @datas = map $_->result,
577	map $fcp->txn_client_get ($_),	834	map $fcp->txn_client_get ($_),
578	@urls;	835	@urls;
579		836
580	Both blocking examples work without the module user having to know	837	Both blocking examples work without the module user having to know
581	anything about events.	838	anything about events.
582		839
583	3a. Event-based in a main program, using any support Event module:	840	3a. Event-based in a main program, using any supported event module:
584		841
585	use Event;	842	use EV;
586		843
587	$fcp->txn_client_get ($url)->cb (sub {	844	$fcp->txn_client_get ($url)->cb (sub {
588	my $txn = shift;	845	my $txn = shift;
589	my $data = $txn->result;	846	my $data = $txn->result;
590	...	847	...
591	});	848	});
592		849
593	Event::loop;	850	EV::loop;
594		851
595	3b. The module user could use AnyEvent, too:	852	3b. The module user could use AnyEvent, too:
596		853
597	use AnyEvent;	854	use AnyEvent;
598		855
…		…
603	$quit->broadcast;	860	$quit->broadcast;
604	});	861	});
605		862
606	$quit->wait;	863	$quit->wait;
607		864
		865
		866	=head1 BENCHMARK
		867
		868	To give you an idea of the performance and overheads that AnyEvent adds
		869	over the event loops themselves (and to give you an impression of the
		870	speed of various event loops), here is a benchmark of various supported
		871	event models natively and with anyevent. The benchmark creates a lot of
		872	timers (with a zero timeout) and io watchers (watching STDOUT, a pty, to
		873	become writable, which it is), lets them fire exactly once and destroys
		874	them again.
		875
		876	=head2 Explanation of the columns
		877
		878	I<watcher> is the number of event watchers created/destroyed. Since
		879	different event models feature vastly different performances, each event
		880	loop was given a number of watchers so that overall runtime is acceptable
		881	and similar between tested event loop (and keep them from crashing): Glib
		882	would probably take thousands of years if asked to process the same number
		883	of watchers as EV in this benchmark.
		884
		885	I<bytes> is the number of bytes (as measured by the resident set size,
		886	RSS) consumed by each watcher. This method of measuring captures both C
		887	and Perl-based overheads.
		888
		889	I<create> is the time, in microseconds (millionths of seconds), that it
		890	takes to create a single watcher. The callback is a closure shared between
		891	all watchers, to avoid adding memory overhead. That means closure creation
		892	and memory usage is not included in the figures.
		893
		894	I<invoke> is the time, in microseconds, used to invoke a simple
		895	callback. The callback simply counts down a Perl variable and after it was
		896	invoked "watcher" times, it would C<< ->broadcast >> a condvar once to
		897	signal the end of this phase.
		898
		899	I<destroy> is the time, in microseconds, that it takes to destroy a single
		900	watcher.
		901
		902	=head2 Results
		903
		904	name watcher bytes create invoke destroy comment
		905	EV/EV 400000 244 0.56 0.46 0.31 EV native interface
		906	EV/Any 100000 610 3.52 0.91 0.75 EV + AnyEvent watchers
		907	CoroEV/Any 100000 610 3.49 0.92 0.75 coroutines + Coro::Signal
		908	Perl/Any 16000 654 4.64 1.22 0.77 pure perl implementation
		909	Event/Event 16000 523 28.05 21.38 0.86 Event native interface
		910	Event/Any 16000 943 34.43 20.48 1.39 Event + AnyEvent watchers
		911	Glib/Any 16000 1357 96.99 12.55 55.51 quadratic behaviour
		912	Tk/Any 2000 1855 27.01 66.61 14.03 SEGV with >> 2000 watchers
		913	POE/Event 2000 6644 108.15 768.19 14.33 via POE::Loop::Event
		914	POE/Select 2000 6343 94.69 807.65 562.69 via POE::Loop::Select
		915
		916	=head2 Discussion
		917
		918	The benchmark does I<not> measure scalability of the event loop very
		919	well. For example, a select-based event loop (such as the pure perl one)
		920	can never compete with an event loop that uses epoll when the number of
		921	file descriptors grows high. In this benchmark, only a single filehandle
		922	is used (although some of the AnyEvent adaptors dup() its file descriptor
		923	to worka round bugs).
		924
		925	C<EV> is the sole leader regarding speed and memory use, which are both
		926	maximal/minimal, respectively. Even when going through AnyEvent, there is
		927	only one event loop that uses less memory (the C<Event> module natively), and
		928	no faster event model, not event C<Event> natively.
		929
		930	The pure perl implementation is hit in a few sweet spots (both the
		931	zero timeout and the use of a single fd hit optimisations in the perl
		932	interpreter and the backend itself). Nevertheless tis shows that it
		933	adds very little overhead in itself. Like any select-based backend its
		934	performance becomes really bad with lots of file descriptors, of course,
		935	but this was not subjetc of this benchmark.
		936
		937	The C<Event> module has a relatively high setup and callback invocation cost,
		938	but overall scores on the third place.
		939
		940	C<Glib>'s memory usage is quite a bit bit higher, features a faster
		941	callback invocation and overall lands in the same class as C<Event>.
		942
		943	The C<Tk> adaptor works relatively well, the fact that it crashes with
		944	more than 2000 watchers is a big setback, however, as correctness takes
		945	precedence over speed. Nevertheless, its performance is surprising, as the
		946	file descriptor is dup()ed for each watcher. This shows that the dup()
		947	employed by some adaptors is not a big performance issue (it does incur a
		948	hidden memory cost inside the kernel, though).
		949
		950	C<POE>, regardless of backend (wether using its pure perl select-based
		951	backend or the Event backend) shows abysmal performance and memory
		952	usage: Watchers use almost 30 times as much memory as EV watchers, and 10
		953	times as much memory as both Event or EV via AnyEvent. Watcher invocation
		954	is almost 700 times slower as with AnyEvent's pure perl implementation.
		955
		956	Summary: using EV through AnyEvent is faster than any other event
		957	loop. The overhead AnyEvent adds can be very small, and you should avoid
		958	POE like the plague if you want performance or reasonable memory usage.
		959
		960
		961	=head1 FORK
		962
		963	Most event libraries are not fork-safe. The ones who are usually are
		964	because they are so inefficient. Only L<EV> is fully fork-aware.
		965
		966	If you have to fork, you must either do so I<before> creating your first
		967	watcher OR you must not use AnyEvent at all in the child.
		968
		969
		970	=head1 SECURITY CONSIDERATIONS
		971
		972	AnyEvent can be forced to load any event model via
		973	$ENV{PERL_ANYEVENT_MODEL}. While this cannot (to my knowledge) be used to
		974	execute arbitrary code or directly gain access, it can easily be used to
		975	make the program hang or malfunction in subtle ways, as AnyEvent watchers
		976	will not be active when the program uses a different event model than
		977	specified in the variable.
		978
		979	You can make AnyEvent completely ignore this variable by deleting it
		980	before the first watcher gets created, e.g. with a C<BEGIN> block:
		981
		982	BEGIN { delete $ENV{PERL_ANYEVENT_MODEL} }
		983
		984	use AnyEvent;
		985
		986
608	=head1 SEE ALSO	987	=head1 SEE ALSO
609		988
610	Event modules: L<Coro::Event>, L<Coro>, L<Event>, L<Glib::Event>, L<Glib>.	989	Event modules: L<Coro::EV>, L<EV>, L<EV::Glib>, L<Glib::EV>,
		990	L<Coro::Event>, L<Event>, L<Glib::Event>, L<Glib>, L<Coro>, L<Tk>,
		991	L<Event::Lib>, L<Qt>, L<POE>.
611		992
		993	Implementations: L<AnyEvent::Impl::CoroEV>, L<AnyEvent::Impl::EV>,
612	Implementations: L<AnyEvent::Impl::Coro>, L<AnyEvent::Impl::Event>, L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>.	994	L<AnyEvent::Impl::CoroEvent>, L<AnyEvent::Impl::Event>, L<AnyEvent::Impl::Glib>,
		995	L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>, L<AnyEvent::Impl::EventLib>,
		996	L<AnyEvent::Impl::Qt>, L<AnyEvent::Impl::POE>.
613		997
614	Nontrivial usage example: L<Net::FCP>.	998	Nontrivial usage examples: L<Net::FCP>, L<Net::XMPP2>.
615		999
616	=head1	1000
		1001	=head1 AUTHOR
		1002
		1003	Marc Lehmann <schmorp@schmorp.de>
		1004	http://home.schmorp.de/
617		1005
618	=cut	1006	=cut
619		1007
620	1	1008	1
621		1009

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Comparing AnyEvent/lib/AnyEvent.pm (file contents): Revision 1.28 by root, Sat Oct 27 15:10:09 2007 UTC vs. Revision 1.71 by root, Fri Apr 25 07:29:42 2008 UTC

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Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.28 by root, Sat Oct 27 15:10:09 2007 UTC vs.
Revision 1.71 by root, Fri Apr 25 07:29:42 2008 UTC