ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/AnyEvent/lib/AnyEvent.pm
(Generate patch)

Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.113 by root, Sat May 10 20:30:35 2008 UTC vs.
Revision 1.148 by root, Sat May 31 00:40:16 2008 UTC

1=head1 NAME 1=head1 => NAME
2 2
3AnyEvent - provide framework for multiple event loops 3AnyEvent - provide framework for multiple event loops
4 4
5EV, Event, Glib, Tk, Perl, Event::Lib, Qt, POE - various supported event loops 5EV, Event, Glib, Tk, Perl, Event::Lib, Qt, POE - various supported event loops
6 6
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 whether a condition was flagged 19 my $w = AnyEvent->condvar; # stores whether a condition was flagged
20 $w->send; # wake up current and all future recv's
20 $w->wait; # enters "main loop" till $condvar gets ->send 21 $w->recv; # enters "main loop" till $condvar gets ->send
21 $w->send; # wake up current and all future wait's 22
23=head1 INTRODUCTION/TUTORIAL
24
25This manpage is mainly a reference manual. If you are interested
26in a tutorial or some gentle introduction, have a look at the
27L<AnyEvent::Intro> manpage.
22 28
23=head1 WHY YOU SHOULD USE THIS MODULE (OR NOT) 29=head1 WHY YOU SHOULD USE THIS MODULE (OR NOT)
24 30
25Glib, POE, IO::Async, Event... CPAN offers event models by the dozen 31Glib, POE, IO::Async, Event... CPAN offers event models by the dozen
26nowadays. So what is different about AnyEvent? 32nowadays. So what is different about AnyEvent?
48isn't itself. What's worse, all the potential users of your module are 54isn't itself. What's worse, all the potential users of your module are
49I<also> forced to use the same event loop you use. 55I<also> forced to use the same event loop you use.
50 56
51AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works 57AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works
52fine. AnyEvent + Tk works fine etc. etc. but none of these work together 58fine. AnyEvent + Tk works fine etc. etc. but none of these work together
53with the rest: POE + IO::Async? no go. Tk + Event? no go. Again: if 59with the rest: POE + IO::Async? No go. Tk + Event? No go. Again: if
54your module uses one of those, every user of your module has to use it, 60your module uses one of those, every user of your module has to use it,
55too. But if your module uses AnyEvent, it works transparently with all 61too. But if your module uses AnyEvent, it works transparently with all
56event models it supports (including stuff like POE and IO::Async, as long 62event models it supports (including stuff like POE and IO::Async, as long
57as those use one of the supported event loops. It is trivial to add new 63as those use one of the supported event loops. It is trivial to add new
58event loops to AnyEvent, too, so it is future-proof). 64event loops to AnyEvent, too, so it is future-proof).
59 65
60In addition to being free of having to use I<the one and only true event 66In addition to being free of having to use I<the one and only true event
61model>, AnyEvent also is free of bloat and policy: with POE or similar 67model>, AnyEvent also is free of bloat and policy: with POE or similar
62modules, you get an enourmous amount of code and strict rules you have to 68modules, you get an enormous amount of code and strict rules you have to
63follow. AnyEvent, on the other hand, is lean and up to the point, by only 69follow. AnyEvent, on the other hand, is lean and up to the point, by only
64offering the functionality that is necessary, in as thin as a wrapper as 70offering the functionality that is necessary, in as thin as a wrapper as
65technically possible. 71technically possible.
66 72
73Of course, AnyEvent comes with a big (and fully optional!) toolbox
74of useful functionality, such as an asynchronous DNS resolver, 100%
75non-blocking connects (even with TLS/SSL, IPv6 and on broken platforms
76such as Windows) and lots of real-world knowledge and workarounds for
77platform bugs and differences.
78
67Of course, if you want lots of policy (this can arguably be somewhat 79Now, if you I<do want> lots of policy (this can arguably be somewhat
68useful) and you want to force your users to use the one and only event 80useful) and you want to force your users to use the one and only event
69model, you should I<not> use this module. 81model, you should I<not> use this module.
70 82
71=head1 DESCRIPTION 83=head1 DESCRIPTION
72 84
102starts using it, all bets are off. Maybe you should tell their authors to 114starts using it, all bets are off. Maybe you should tell their authors to
103use AnyEvent so their modules work together with others seamlessly... 115use AnyEvent so their modules work together with others seamlessly...
104 116
105The pure-perl implementation of AnyEvent is called 117The pure-perl implementation of AnyEvent is called
106C<AnyEvent::Impl::Perl>. Like other event modules you can load it 118C<AnyEvent::Impl::Perl>. Like other event modules you can load it
107explicitly. 119explicitly and enjoy the high availability of that event loop :)
108 120
109=head1 WATCHERS 121=head1 WATCHERS
110 122
111AnyEvent has the central concept of a I<watcher>, which is an object that 123AnyEvent has the central concept of a I<watcher>, which is an object that
112stores relevant data for each kind of event you are waiting for, such as 124stores relevant data for each kind of event you are waiting for, such as
113the callback to call, the filehandle to watch, etc. 125the callback to call, the file handle to watch, etc.
114 126
115These watchers are normal Perl objects with normal Perl lifetime. After 127These watchers are normal Perl objects with normal Perl lifetime. After
116creating a watcher it will immediately "watch" for events and invoke the 128creating a watcher it will immediately "watch" for events and invoke the
117callback when the event occurs (of course, only when the event model 129callback when the event occurs (of course, only when the event model
118is in control). 130is in control).
227timers. 239timers.
228 240
229AnyEvent always prefers relative timers, if available, matching the 241AnyEvent always prefers relative timers, if available, matching the
230AnyEvent API. 242AnyEvent API.
231 243
244AnyEvent has two additional methods that return the "current time":
245
246=over 4
247
248=item AnyEvent->time
249
250This returns the "current wallclock time" as a fractional number of
251seconds since the Epoch (the same thing as C<time> or C<Time::HiRes::time>
252return, and the result is guaranteed to be compatible with those).
253
254It progresses independently of any event loop processing, i.e. each call
255will check the system clock, which usually gets updated frequently.
256
257=item AnyEvent->now
258
259This also returns the "current wallclock time", but unlike C<time>, above,
260this value might change only once per event loop iteration, depending on
261the event loop (most return the same time as C<time>, above). This is the
262time that AnyEvent's timers get scheduled against.
263
264I<In almost all cases (in all cases if you don't care), this is the
265function to call when you want to know the current time.>
266
267This function is also often faster then C<< AnyEvent->time >>, and
268thus the preferred method if you want some timestamp (for example,
269L<AnyEvent::Handle> uses this to update it's activity timeouts).
270
271The rest of this section is only of relevance if you try to be very exact
272with your timing, you can skip it without bad conscience.
273
274For a practical example of when these times differ, consider L<Event::Lib>
275and L<EV> and the following set-up:
276
277The event loop is running and has just invoked one of your callback at
278time=500 (assume no other callbacks delay processing). In your callback,
279you wait a second by executing C<sleep 1> (blocking the process for a
280second) and then (at time=501) you create a relative timer that fires
281after three seconds.
282
283With L<Event::Lib>, C<< AnyEvent->time >> and C<< AnyEvent->now >> will
284both return C<501>, because that is the current time, and the timer will
285be scheduled to fire at time=504 (C<501> + C<3>).
286
287With L<EV>, C<< AnyEvent->time >> returns C<501> (as that is the current
288time), but C<< AnyEvent->now >> returns C<500>, as that is the time the
289last event processing phase started. With L<EV>, your timer gets scheduled
290to run at time=503 (C<500> + C<3>).
291
292In one sense, L<Event::Lib> is more exact, as it uses the current time
293regardless of any delays introduced by event processing. However, most
294callbacks do not expect large delays in processing, so this causes a
295higher drift (and a lot more system calls to get the current time).
296
297In another sense, L<EV> is more exact, as your timer will be scheduled at
298the same time, regardless of how long event processing actually took.
299
300In either case, if you care (and in most cases, you don't), then you
301can get whatever behaviour you want with any event loop, by taking the
302difference between C<< AnyEvent->time >> and C<< AnyEvent->now >> into
303account.
304
305=back
306
232=head2 SIGNAL WATCHERS 307=head2 SIGNAL WATCHERS
233 308
234You can watch for signals using a signal watcher, C<signal> is the signal 309You can watch for signals using a signal watcher, C<signal> is the signal
235I<name> without any C<SIG> prefix, C<cb> is the Perl callback to 310I<name> without any C<SIG> prefix, C<cb> is the Perl callback to
236be invoked whenever a signal occurs. 311be invoked whenever a signal occurs.
237 312
238Although the callback might get passed parameters, their value and 313Although the callback might get passed parameters, their value and
239presence is undefined and you cannot rely on them. Portable AnyEvent 314presence is undefined and you cannot rely on them. Portable AnyEvent
240callbacks cannot use arguments passed to signal watcher callbacks. 315callbacks cannot use arguments passed to signal watcher callbacks.
241 316
242Multiple signal occurances can be clumped together into one callback 317Multiple signal occurrences can be clumped together into one callback
243invocation, and callback invocation will be synchronous. synchronous means 318invocation, and callback invocation will be synchronous. Synchronous means
244that it might take a while until the signal gets handled by the process, 319that it might take a while until the signal gets handled by the process,
245but it is guarenteed not to interrupt any other callbacks. 320but it is guaranteed not to interrupt any other callbacks.
246 321
247The main advantage of using these watchers is that you can share a signal 322The main advantage of using these watchers is that you can share a signal
248between multiple watchers. 323between multiple watchers.
249 324
250This watcher might use C<%SIG>, so programs overwriting those signals 325This watcher might use C<%SIG>, so programs overwriting those signals
278C<fork> the child (alternatively, you can call C<AnyEvent::detect>). 353C<fork> the child (alternatively, you can call C<AnyEvent::detect>).
279 354
280Example: fork a process and wait for it 355Example: fork a process and wait for it
281 356
282 my $done = AnyEvent->condvar; 357 my $done = AnyEvent->condvar;
283
284 AnyEvent::detect; # force event module to be initialised
285 358
286 my $pid = fork or exit 5; 359 my $pid = fork or exit 5;
287 360
288 my $w = AnyEvent->child ( 361 my $w = AnyEvent->child (
289 pid => $pid, 362 pid => $pid,
293 $done->send; 366 $done->send;
294 }, 367 },
295 ); 368 );
296 369
297 # do something else, then wait for process exit 370 # do something else, then wait for process exit
298 $done->wait; 371 $done->recv;
299 372
300=head2 CONDITION VARIABLES 373=head2 CONDITION VARIABLES
301 374
302If you are familiar with some event loops you will know that all of them 375If you are familiar with some event loops you will know that all of them
303require you to run some blocking "loop", "run" or similar function that 376require you to run some blocking "loop", "run" or similar function that
312Condition variables can be created by calling the C<< AnyEvent->condvar 385Condition variables can be created by calling the C<< AnyEvent->condvar
313>> method, usually without arguments. The only argument pair allowed is 386>> method, usually without arguments. The only argument pair allowed is
314C<cb>, which specifies a callback to be called when the condition variable 387C<cb>, which specifies a callback to be called when the condition variable
315becomes true. 388becomes true.
316 389
317After creation, the conditon variable is "false" until it becomes "true" 390After creation, the condition variable is "false" until it becomes "true"
318by calling the C<send> method. 391by calling the C<send> method (or calling the condition variable as if it
392were a callback, read about the caveats in the description for the C<<
393->send >> method).
319 394
320Condition variables are similar to callbacks, except that you can 395Condition variables are similar to callbacks, except that you can
321optionally wait for them. They can also be called merge points - points 396optionally wait for them. They can also be called merge points - points
322in time where multiple outstandign events have been processed. And yet 397in time where multiple outstanding events have been processed. And yet
323another way to call them is transations - each condition variable can be 398another way to call them is transactions - each condition variable can be
324used to represent a transaction, which finishes at some point and delivers 399used to represent a transaction, which finishes at some point and delivers
325a result. 400a result.
326 401
327Condition variables are very useful to signal that something has finished, 402Condition variables are very useful to signal that something has finished,
328for example, if you write a module that does asynchronous http requests, 403for example, if you write a module that does asynchronous http requests,
329then a condition variable would be the ideal candidate to signal the 404then a condition variable would be the ideal candidate to signal the
330availability of results. The user can either act when the callback is 405availability of results. The user can either act when the callback is
331called or can synchronously C<< ->wait >> for the results. 406called or can synchronously C<< ->recv >> for the results.
332 407
333You can also use them to simulate traditional event loops - for example, 408You can also use them to simulate traditional event loops - for example,
334you can block your main program until an event occurs - for example, you 409you can block your main program until an event occurs - for example, you
335could C<< ->wait >> in your main program until the user clicks the Quit 410could C<< ->recv >> in your main program until the user clicks the Quit
336button of your app, which would C<< ->send >> the "quit" event. 411button of your app, which would C<< ->send >> the "quit" event.
337 412
338Note that condition variables recurse into the event loop - if you have 413Note that condition variables recurse into the event loop - if you have
339two pieces of code that call C<< ->wait >> in a round-robbin fashion, you 414two pieces of code that call C<< ->recv >> in a round-robin fashion, you
340lose. Therefore, condition variables are good to export to your caller, but 415lose. Therefore, condition variables are good to export to your caller, but
341you should avoid making a blocking wait yourself, at least in callbacks, 416you should avoid making a blocking wait yourself, at least in callbacks,
342as this asks for trouble. 417as this asks for trouble.
343 418
344Condition variables are represented by hash refs in perl, and the keys 419Condition variables are represented by hash refs in perl, and the keys
349 424
350There are two "sides" to a condition variable - the "producer side" which 425There are two "sides" to a condition variable - the "producer side" which
351eventually calls C<< -> send >>, and the "consumer side", which waits 426eventually calls C<< -> send >>, and the "consumer side", which waits
352for the send to occur. 427for the send to occur.
353 428
354Example: 429Example: wait for a timer.
355 430
356 # wait till the result is ready 431 # wait till the result is ready
357 my $result_ready = AnyEvent->condvar; 432 my $result_ready = AnyEvent->condvar;
358 433
359 # do something such as adding a timer 434 # do something such as adding a timer
365 cb => sub { $result_ready->send }, 440 cb => sub { $result_ready->send },
366 ); 441 );
367 442
368 # this "blocks" (while handling events) till the callback 443 # this "blocks" (while handling events) till the callback
369 # calls send 444 # calls send
370 $result_ready->wait; 445 $result_ready->recv;
446
447Example: wait for a timer, but take advantage of the fact that
448condition variables are also code references.
449
450 my $done = AnyEvent->condvar;
451 my $delay = AnyEvent->timer (after => 5, cb => $done);
452 $done->recv;
371 453
372=head3 METHODS FOR PRODUCERS 454=head3 METHODS FOR PRODUCERS
373 455
374These methods should only be used by the producing side, i.e. the 456These methods should only be used by the producing side, i.e. the
375code/module that eventually sends the signal. Note that it is also 457code/module that eventually sends the signal. Note that it is also
378 460
379=over 4 461=over 4
380 462
381=item $cv->send (...) 463=item $cv->send (...)
382 464
383Flag the condition as ready - a running C<< ->wait >> and all further 465Flag the condition as ready - a running C<< ->recv >> and all further
384calls to C<wait> will (eventually) return after this method has been 466calls to C<recv> will (eventually) return after this method has been
385called. If nobody is waiting the send will be remembered. 467called. If nobody is waiting the send will be remembered.
386 468
387If a callback has been set on the condition variable, it is called 469If a callback has been set on the condition variable, it is called
388immediately from within send. 470immediately from within send.
389 471
390Any arguments passed to the C<send> call will be returned by all 472Any arguments passed to the C<send> call will be returned by all
391future C<< ->wait >> calls. 473future C<< ->recv >> calls.
474
475Condition variables are overloaded so one can call them directly
476(as a code reference). Calling them directly is the same as calling
477C<send>. Note, however, that many C-based event loops do not handle
478overloading, so as tempting as it may be, passing a condition variable
479instead of a callback does not work. Both the pure perl and EV loops
480support overloading, however, as well as all functions that use perl to
481invoke a callback (as in L<AnyEvent::Socket> and L<AnyEvent::DNS> for
482example).
392 483
393=item $cv->croak ($error) 484=item $cv->croak ($error)
394 485
395Similar to send, but causes all call's wait C<< ->wait >> to invoke 486Similar to send, but causes all call's to C<< ->recv >> to invoke
396C<Carp::croak> with the given error message/object/scalar. 487C<Carp::croak> with the given error message/object/scalar.
397 488
398This can be used to signal any errors to the condition variable 489This can be used to signal any errors to the condition variable
399user/consumer. 490user/consumer.
400 491
401=item $cv->begin ([group callback]) 492=item $cv->begin ([group callback])
402 493
403=item $cv->end 494=item $cv->end
495
496These two methods are EXPERIMENTAL and MIGHT CHANGE.
404 497
405These two methods can be used to combine many transactions/events into 498These two methods can be used to combine many transactions/events into
406one. For example, a function that pings many hosts in parallel might want 499one. For example, a function that pings many hosts in parallel might want
407to use a condition variable for the whole process. 500to use a condition variable for the whole process.
408 501
443doesn't execute once). 536doesn't execute once).
444 537
445This is the general pattern when you "fan out" into multiple subrequests: 538This is the general pattern when you "fan out" into multiple subrequests:
446use an outer C<begin>/C<end> pair to set the callback and ensure C<end> 539use an outer C<begin>/C<end> pair to set the callback and ensure C<end>
447is called at least once, and then, for each subrequest you start, call 540is called at least once, and then, for each subrequest you start, call
448C<begin> and for eahc subrequest you finish, call C<end>. 541C<begin> and for each subrequest you finish, call C<end>.
449 542
450=back 543=back
451 544
452=head3 METHODS FOR CONSUMERS 545=head3 METHODS FOR CONSUMERS
453 546
454These methods should only be used by the consuming side, i.e. the 547These methods should only be used by the consuming side, i.e. the
455code awaits the condition. 548code awaits the condition.
456 549
457=over 4 550=over 4
458 551
459=item $cv->wait 552=item $cv->recv
460 553
461Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak 554Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak
462>> methods have been called on c<$cv>, while servicing other watchers 555>> methods have been called on c<$cv>, while servicing other watchers
463normally. 556normally.
464 557
475(programs might want to do that to stay interactive), so I<if you are 568(programs might want to do that to stay interactive), so I<if you are
476using this from a module, never require a blocking wait>, but let the 569using this from a module, never require a blocking wait>, but let the
477caller decide whether the call will block or not (for example, by coupling 570caller decide whether the call will block or not (for example, by coupling
478condition variables with some kind of request results and supporting 571condition variables with some kind of request results and supporting
479callbacks so the caller knows that getting the result will not block, 572callbacks so the caller knows that getting the result will not block,
480while still suppporting blocking waits if the caller so desires). 573while still supporting blocking waits if the caller so desires).
481 574
482Another reason I<never> to C<< ->wait >> in a module is that you cannot 575Another reason I<never> to C<< ->recv >> in a module is that you cannot
483sensibly have two C<< ->wait >>'s in parallel, as that would require 576sensibly have two C<< ->recv >>'s in parallel, as that would require
484multiple interpreters or coroutines/threads, none of which C<AnyEvent> 577multiple interpreters or coroutines/threads, none of which C<AnyEvent>
485can supply. 578can supply.
486 579
487The L<Coro> module, however, I<can> and I<does> supply coroutines and, in 580The L<Coro> module, however, I<can> and I<does> supply coroutines and, in
488fact, L<Coro::AnyEvent> replaces AnyEvent's condvars by coroutine-safe 581fact, L<Coro::AnyEvent> replaces AnyEvent's condvars by coroutine-safe
489versions and also integrates coroutines into AnyEvent, making blocking 582versions and also integrates coroutines into AnyEvent, making blocking
490C<< ->wait >> calls perfectly safe as long as they are done from another 583C<< ->recv >> calls perfectly safe as long as they are done from another
491coroutine (one that doesn't run the event loop). 584coroutine (one that doesn't run the event loop).
492 585
493You can ensure that C<< -wait >> never blocks by setting a callback and 586You can ensure that C<< -recv >> never blocks by setting a callback and
494only calling C<< ->wait >> from within that callback (or at a later 587only calling C<< ->recv >> from within that callback (or at a later
495time). This will work even when the event loop does not support blocking 588time). This will work even when the event loop does not support blocking
496waits otherwise. 589waits otherwise.
497 590
498=item $bool = $cv->ready 591=item $bool = $cv->ready
499 592
504 597
505This is a mutator function that returns the callback set and optionally 598This is a mutator function that returns the callback set and optionally
506replaces it before doing so. 599replaces it before doing so.
507 600
508The callback will be called when the condition becomes "true", i.e. when 601The callback will be called when the condition becomes "true", i.e. when
509C<send> or C<croak> are called. Calling C<wait> inside the callback 602C<send> or C<croak> are called. Calling C<recv> inside the callback
510or at any later time is guaranteed not to block. 603or at any later time is guaranteed not to block.
511 604
512=back 605=back
513 606
514=head1 GLOBAL VARIABLES AND FUNCTIONS 607=head1 GLOBAL VARIABLES AND FUNCTIONS
582Be careful when you create watchers in the module body - AnyEvent will 675Be careful when you create watchers in the module body - AnyEvent will
583decide which event module to use as soon as the first method is called, so 676decide which event module to use as soon as the first method is called, so
584by calling AnyEvent in your module body you force the user of your module 677by calling AnyEvent in your module body you force the user of your module
585to load the event module first. 678to load the event module first.
586 679
587Never call C<< ->wait >> on a condition variable unless you I<know> that 680Never call C<< ->recv >> on a condition variable unless you I<know> that
588the C<< ->send >> method has been called on it already. This is 681the C<< ->send >> method has been called on it already. This is
589because it will stall the whole program, and the whole point of using 682because it will stall the whole program, and the whole point of using
590events is to stay interactive. 683events is to stay interactive.
591 684
592It is fine, however, to call C<< ->wait >> when the user of your module 685It is fine, however, to call C<< ->recv >> when the user of your module
593requests it (i.e. if you create a http request object ad have a method 686requests it (i.e. if you create a http request object ad have a method
594called C<results> that returns the results, it should call C<< ->wait >> 687called C<results> that returns the results, it should call C<< ->recv >>
595freely, as the user of your module knows what she is doing. always). 688freely, as the user of your module knows what she is doing. always).
596 689
597=head1 WHAT TO DO IN THE MAIN PROGRAM 690=head1 WHAT TO DO IN THE MAIN PROGRAM
598 691
599There will always be a single main program - the only place that should 692There will always be a single main program - the only place that should
601 694
602If it doesn't care, it can just "use AnyEvent" and use it itself, or not 695If it doesn't care, it can just "use AnyEvent" and use it itself, or not
603do anything special (it does not need to be event-based) and let AnyEvent 696do anything special (it does not need to be event-based) and let AnyEvent
604decide which implementation to chose if some module relies on it. 697decide which implementation to chose if some module relies on it.
605 698
606If the main program relies on a specific event model. For example, in 699If the main program relies on a specific event model - for example, in
607Gtk2 programs you have to rely on the Glib module. You should load the 700Gtk2 programs you have to rely on the Glib module - you should load the
608event module before loading AnyEvent or any module that uses it: generally 701event module before loading AnyEvent or any module that uses it: generally
609speaking, you should load it as early as possible. The reason is that 702speaking, you should load it as early as possible. The reason is that
610modules might create watchers when they are loaded, and AnyEvent will 703modules might create watchers when they are loaded, and AnyEvent will
611decide on the event model to use as soon as it creates watchers, and it 704decide on the event model to use as soon as it creates watchers, and it
612might chose the wrong one unless you load the correct one yourself. 705might chose the wrong one unless you load the correct one yourself.
613 706
614You can chose to use a rather inefficient pure-perl implementation by 707You can chose to use a pure-perl implementation by loading the
615loading the C<AnyEvent::Impl::Perl> module, which gives you similar 708C<AnyEvent::Impl::Perl> module, which gives you similar behaviour
616behaviour everywhere, but letting AnyEvent chose is generally better. 709everywhere, but letting AnyEvent chose the model is generally better.
710
711=head2 MAINLOOP EMULATION
712
713Sometimes (often for short test scripts, or even standalone programs who
714only want to use AnyEvent), you do not want to run a specific event loop.
715
716In that case, you can use a condition variable like this:
717
718 AnyEvent->condvar->recv;
719
720This has the effect of entering the event loop and looping forever.
721
722Note that usually your program has some exit condition, in which case
723it is better to use the "traditional" approach of storing a condition
724variable somewhere, waiting for it, and sending it when the program should
725exit cleanly.
726
617 727
618=head1 OTHER MODULES 728=head1 OTHER MODULES
619 729
620The following is a non-exhaustive list of additional modules that use 730The following is a non-exhaustive list of additional modules that use
621AnyEvent and can therefore be mixed easily with other AnyEvent modules 731AnyEvent and can therefore be mixed easily with other AnyEvent modules
631 741
632=item L<AnyEvent::Handle> 742=item L<AnyEvent::Handle>
633 743
634Provide read and write buffers and manages watchers for reads and writes. 744Provide read and write buffers and manages watchers for reads and writes.
635 745
746=item L<AnyEvent::Socket>
747
748Provides various utility functions for (internet protocol) sockets,
749addresses and name resolution. Also functions to create non-blocking tcp
750connections or tcp servers, with IPv6 and SRV record support and more.
751
752=item L<AnyEvent::DNS>
753
754Provides rich asynchronous DNS resolver capabilities.
755
636=item L<AnyEvent::HTTPD> 756=item L<AnyEvent::HTTPD>
637 757
638Provides a simple web application server framework. 758Provides a simple web application server framework.
639
640=item L<AnyEvent::DNS>
641
642Provides asynchronous DNS resolver capabilities, beyond what
643L<AnyEvent::Util> offers.
644 759
645=item L<AnyEvent::FastPing> 760=item L<AnyEvent::FastPing>
646 761
647The fastest ping in the west. 762The fastest ping in the west.
648 763
691no warnings; 806no warnings;
692use strict; 807use strict;
693 808
694use Carp; 809use Carp;
695 810
696our $VERSION = '3.4'; 811our $VERSION = 4.11;
697our $MODEL; 812our $MODEL;
698 813
699our $AUTOLOAD; 814our $AUTOLOAD;
700our @ISA; 815our @ISA;
701 816
817our @REGISTRY;
818
819our $WIN32;
820
821BEGIN {
822 my $win32 = ! ! ($^O =~ /mswin32/i);
823 eval "sub WIN32(){ $win32 }";
824}
825
702our $verbose = $ENV{PERL_ANYEVENT_VERBOSE}*1; 826our $verbose = $ENV{PERL_ANYEVENT_VERBOSE}*1;
703 827
704our @REGISTRY; 828our %PROTOCOL; # (ipv4|ipv6) => (1|2), higher numbers are preferred
829
830{
831 my $idx;
832 $PROTOCOL{$_} = ++$idx
833 for reverse split /\s*,\s*/,
834 $ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6";
835}
705 836
706my @models = ( 837my @models = (
707 [EV:: => AnyEvent::Impl::EV::], 838 [EV:: => AnyEvent::Impl::EV::],
708 [Event:: => AnyEvent::Impl::Event::], 839 [Event:: => AnyEvent::Impl::Event::],
709 [Tk:: => AnyEvent::Impl::Tk::],
710 [Wx:: => AnyEvent::Impl::POE::],
711 [Prima:: => AnyEvent::Impl::POE::],
712 [AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::], 840 [AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::],
713 # everything below here will not be autoprobed as the pureperl backend should work everywhere 841 # everything below here will not be autoprobed
714 [Glib:: => AnyEvent::Impl::Glib::], 842 # as the pureperl backend should work everywhere
843 # and is usually faster
844 [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
845 [Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers
715 [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy 846 [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
716 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program 847 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program
717 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza 848 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
849 [Wx:: => AnyEvent::Impl::POE::],
850 [Prima:: => AnyEvent::Impl::POE::],
718); 851);
719 852
720our %method = map +($_ => 1), qw(io timer signal child condvar one_event DESTROY); 853our %method = map +($_ => 1), qw(io timer time now signal child condvar one_event DESTROY);
721 854
722our @post_detect; 855our @post_detect;
723 856
724sub post_detect(&) { 857sub post_detect(&) {
725 my ($cb) = @_; 858 my ($cb) = @_;
730 1 863 1
731 } else { 864 } else {
732 push @post_detect, $cb; 865 push @post_detect, $cb;
733 866
734 defined wantarray 867 defined wantarray
735 ? bless \$cb, "AnyEvent::Util::Guard" 868 ? bless \$cb, "AnyEvent::Util::PostDetect"
736 : () 869 : ()
737 } 870 }
738} 871}
739 872
740sub AnyEvent::Util::Guard::DESTROY { 873sub AnyEvent::Util::PostDetect::DESTROY {
741 @post_detect = grep $_ != ${$_[0]}, @post_detect; 874 @post_detect = grep $_ != ${$_[0]}, @post_detect;
742} 875}
743 876
744sub detect() { 877sub detect() {
745 unless ($MODEL) { 878 unless ($MODEL) {
746 no strict 'refs'; 879 no strict 'refs';
880 local $SIG{__DIE__};
747 881
748 if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) { 882 if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {
749 my $model = "AnyEvent::Impl::$1"; 883 my $model = "AnyEvent::Impl::$1";
750 if (eval "require $model") { 884 if (eval "require $model") {
751 $MODEL = $model; 885 $MODEL = $model;
808 $class->$func (@_); 942 $class->$func (@_);
809} 943}
810 944
811package AnyEvent::Base; 945package AnyEvent::Base;
812 946
947# default implementation for now and time
948
949use Time::HiRes ();
950
951sub time { Time::HiRes::time }
952sub now { Time::HiRes::time }
953
813# default implementation for ->condvar, ->wait, ->broadcast 954# default implementation for ->condvar
814 955
815sub condvar { 956sub condvar {
816 bless \my $flag, "AnyEvent::Base::CondVar" 957 bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, AnyEvent::CondVar::
817}
818
819sub AnyEvent::Base::CondVar::broadcast {
820 ${$_[0]}++;
821}
822
823sub AnyEvent::Base::CondVar::wait {
824 AnyEvent->one_event while !${$_[0]};
825} 958}
826 959
827# default implementation for ->signal 960# default implementation for ->signal
828 961
829our %SIG_CB; 962our %SIG_CB;
882 or Carp::croak "required option 'pid' is missing"; 1015 or Carp::croak "required option 'pid' is missing";
883 1016
884 $PID_CB{$pid}{$arg{cb}} = $arg{cb}; 1017 $PID_CB{$pid}{$arg{cb}} = $arg{cb};
885 1018
886 unless ($WNOHANG) { 1019 unless ($WNOHANG) {
887 $WNOHANG = eval { require POSIX; &POSIX::WNOHANG } || 1; 1020 $WNOHANG = eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1;
888 } 1021 }
889 1022
890 unless ($CHLD_W) { 1023 unless ($CHLD_W) {
891 $CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld); 1024 $CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld);
892 # child could be a zombie already, so make at least one round 1025 # child could be a zombie already, so make at least one round
902 delete $PID_CB{$pid}{$cb}; 1035 delete $PID_CB{$pid}{$cb};
903 delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} }; 1036 delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };
904 1037
905 undef $CHLD_W unless keys %PID_CB; 1038 undef $CHLD_W unless keys %PID_CB;
906} 1039}
1040
1041package AnyEvent::CondVar;
1042
1043our @ISA = AnyEvent::CondVar::Base::;
1044
1045package AnyEvent::CondVar::Base;
1046
1047use overload
1048 '&{}' => sub { my $self = shift; sub { $self->send (@_) } },
1049 fallback => 1;
1050
1051sub _send {
1052 # nop
1053}
1054
1055sub send {
1056 my $cv = shift;
1057 $cv->{_ae_sent} = [@_];
1058 (delete $cv->{_ae_cb})->($cv) if $cv->{_ae_cb};
1059 $cv->_send;
1060}
1061
1062sub croak {
1063 $_[0]{_ae_croak} = $_[1];
1064 $_[0]->send;
1065}
1066
1067sub ready {
1068 $_[0]{_ae_sent}
1069}
1070
1071sub _wait {
1072 AnyEvent->one_event while !$_[0]{_ae_sent};
1073}
1074
1075sub recv {
1076 $_[0]->_wait;
1077
1078 Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak};
1079 wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0]
1080}
1081
1082sub cb {
1083 $_[0]{_ae_cb} = $_[1] if @_ > 1;
1084 $_[0]{_ae_cb}
1085}
1086
1087sub begin {
1088 ++$_[0]{_ae_counter};
1089 $_[0]{_ae_end_cb} = $_[1] if @_ > 1;
1090}
1091
1092sub end {
1093 return if --$_[0]{_ae_counter};
1094 &{ $_[0]{_ae_end_cb} || sub { $_[0]->send } };
1095}
1096
1097# undocumented/compatibility with pre-3.4
1098*broadcast = \&send;
1099*wait = \&_wait;
907 1100
908=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE 1101=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE
909 1102
910This is an advanced topic that you do not normally need to use AnyEvent in 1103This is an advanced topic that you do not normally need to use AnyEvent in
911a module. This section is only of use to event loop authors who want to 1104a module. This section is only of use to event loop authors who want to
968model it chooses. 1161model it chooses.
969 1162
970=item C<PERL_ANYEVENT_MODEL> 1163=item C<PERL_ANYEVENT_MODEL>
971 1164
972This can be used to specify the event model to be used by AnyEvent, before 1165This can be used to specify the event model to be used by AnyEvent, before
973autodetection and -probing kicks in. It must be a string consisting 1166auto detection and -probing kicks in. It must be a string consisting
974entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended 1167entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended
975and the resulting module name is loaded and if the load was successful, 1168and the resulting module name is loaded and if the load was successful,
976used as event model. If it fails to load AnyEvent will proceed with 1169used as event model. If it fails to load AnyEvent will proceed with
977autodetection and -probing. 1170auto detection and -probing.
978 1171
979This functionality might change in future versions. 1172This functionality might change in future versions.
980 1173
981For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you 1174For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you
982could start your program like this: 1175could start your program like this:
983 1176
984 PERL_ANYEVENT_MODEL=Perl perl ... 1177 PERL_ANYEVENT_MODEL=Perl perl ...
1178
1179=item C<PERL_ANYEVENT_PROTOCOLS>
1180
1181Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences
1182for IPv4 or IPv6. The default is unspecified (and might change, or be the result
1183of auto probing).
1184
1185Must be set to a comma-separated list of protocols or address families,
1186current supported: C<ipv4> and C<ipv6>. Only protocols mentioned will be
1187used, and preference will be given to protocols mentioned earlier in the
1188list.
1189
1190This variable can effectively be used for denial-of-service attacks
1191against local programs (e.g. when setuid), although the impact is likely
1192small, as the program has to handle connection errors already-
1193
1194Examples: C<PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6> - prefer IPv4 over IPv6,
1195but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4>
1196- only support IPv4, never try to resolve or contact IPv6
1197addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or
1198IPv6, but prefer IPv6 over IPv4.
1199
1200=item C<PERL_ANYEVENT_EDNS0>
1201
1202Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension
1203for DNS. This extension is generally useful to reduce DNS traffic, but
1204some (broken) firewalls drop such DNS packets, which is why it is off by
1205default.
1206
1207Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce
1208EDNS0 in its DNS requests.
1209
1210=item C<PERL_ANYEVENT_MAX_FORKS>
1211
1212The maximum number of child processes that C<AnyEvent::Util::fork_call>
1213will create in parallel.
985 1214
986=back 1215=back
987 1216
988=head1 EXAMPLE PROGRAM 1217=head1 EXAMPLE PROGRAM
989 1218
1000 poll => 'r', 1229 poll => 'r',
1001 cb => sub { 1230 cb => sub {
1002 warn "io event <$_[0]>\n"; # will always output <r> 1231 warn "io event <$_[0]>\n"; # will always output <r>
1003 chomp (my $input = <STDIN>); # read a line 1232 chomp (my $input = <STDIN>); # read a line
1004 warn "read: $input\n"; # output what has been read 1233 warn "read: $input\n"; # output what has been read
1005 $cv->broadcast if $input =~ /^q/i; # quit program if /^q/i 1234 $cv->send if $input =~ /^q/i; # quit program if /^q/i
1006 }, 1235 },
1007 ); 1236 );
1008 1237
1009 my $time_watcher; # can only be used once 1238 my $time_watcher; # can only be used once
1010 1239
1015 }); 1244 });
1016 } 1245 }
1017 1246
1018 new_timer; # create first timer 1247 new_timer; # create first timer
1019 1248
1020 $cv->wait; # wait until user enters /^q/i 1249 $cv->recv; # wait until user enters /^q/i
1021 1250
1022=head1 REAL-WORLD EXAMPLE 1251=head1 REAL-WORLD EXAMPLE
1023 1252
1024Consider the L<Net::FCP> module. It features (among others) the following 1253Consider the L<Net::FCP> module. It features (among others) the following
1025API calls, which are to freenet what HTTP GET requests are to http: 1254API calls, which are to freenet what HTTP GET requests are to http:
1075 syswrite $txn->{fh}, $txn->{request} 1304 syswrite $txn->{fh}, $txn->{request}
1076 or die "connection or write error"; 1305 or die "connection or write error";
1077 $txn->{w} = AnyEvent->io (fh => $txn->{fh}, poll => 'r', cb => sub { $txn->fh_ready_r }); 1306 $txn->{w} = AnyEvent->io (fh => $txn->{fh}, poll => 'r', cb => sub { $txn->fh_ready_r });
1078 1307
1079Again, C<fh_ready_r> waits till all data has arrived, and then stores the 1308Again, C<fh_ready_r> waits till all data has arrived, and then stores the
1080result and signals any possible waiters that the request ahs finished: 1309result and signals any possible waiters that the request has finished:
1081 1310
1082 sysread $txn->{fh}, $txn->{buf}, length $txn->{$buf}; 1311 sysread $txn->{fh}, $txn->{buf}, length $txn->{$buf};
1083 1312
1084 if (end-of-file or data complete) { 1313 if (end-of-file or data complete) {
1085 $txn->{result} = $txn->{buf}; 1314 $txn->{result} = $txn->{buf};
1086 $txn->{finished}->broadcast; 1315 $txn->{finished}->send;
1087 $txb->{cb}->($txn) of $txn->{cb}; # also call callback 1316 $txb->{cb}->($txn) of $txn->{cb}; # also call callback
1088 } 1317 }
1089 1318
1090The C<result> method, finally, just waits for the finished signal (if the 1319The C<result> method, finally, just waits for the finished signal (if the
1091request was already finished, it doesn't wait, of course, and returns the 1320request was already finished, it doesn't wait, of course, and returns the
1092data: 1321data:
1093 1322
1094 $txn->{finished}->wait; 1323 $txn->{finished}->recv;
1095 return $txn->{result}; 1324 return $txn->{result};
1096 1325
1097The actual code goes further and collects all errors (C<die>s, exceptions) 1326The actual code goes further and collects all errors (C<die>s, exceptions)
1098that occured during request processing. The C<result> method detects 1327that occurred during request processing. The C<result> method detects
1099whether an exception as thrown (it is stored inside the $txn object) 1328whether an exception as thrown (it is stored inside the $txn object)
1100and just throws the exception, which means connection errors and other 1329and just throws the exception, which means connection errors and other
1101problems get reported tot he code that tries to use the result, not in a 1330problems get reported tot he code that tries to use the result, not in a
1102random callback. 1331random callback.
1103 1332
1134 1363
1135 my $quit = AnyEvent->condvar; 1364 my $quit = AnyEvent->condvar;
1136 1365
1137 $fcp->txn_client_get ($url)->cb (sub { 1366 $fcp->txn_client_get ($url)->cb (sub {
1138 ... 1367 ...
1139 $quit->broadcast; 1368 $quit->send;
1140 }); 1369 });
1141 1370
1142 $quit->wait; 1371 $quit->recv;
1143 1372
1144 1373
1145=head1 BENCHMARKS 1374=head1 BENCHMARKS
1146 1375
1147To give you an idea of the performance and overheads that AnyEvent adds 1376To give you an idea of the performance and overheads that AnyEvent adds
1149of various event loops I prepared some benchmarks. 1378of various event loops I prepared some benchmarks.
1150 1379
1151=head2 BENCHMARKING ANYEVENT OVERHEAD 1380=head2 BENCHMARKING ANYEVENT OVERHEAD
1152 1381
1153Here is a benchmark of various supported event models used natively and 1382Here is a benchmark of various supported event models used natively and
1154through anyevent. The benchmark creates a lot of timers (with a zero 1383through AnyEvent. The benchmark creates a lot of timers (with a zero
1155timeout) and I/O watchers (watching STDOUT, a pty, to become writable, 1384timeout) and I/O watchers (watching STDOUT, a pty, to become writable,
1156which it is), lets them fire exactly once and destroys them again. 1385which it is), lets them fire exactly once and destroys them again.
1157 1386
1158Source code for this benchmark is found as F<eg/bench> in the AnyEvent 1387Source code for this benchmark is found as F<eg/bench> in the AnyEvent
1159distribution. 1388distribution.
1176all watchers, to avoid adding memory overhead. That means closure creation 1405all watchers, to avoid adding memory overhead. That means closure creation
1177and memory usage is not included in the figures. 1406and memory usage is not included in the figures.
1178 1407
1179I<invoke> is the time, in microseconds, used to invoke a simple 1408I<invoke> is the time, in microseconds, used to invoke a simple
1180callback. The callback simply counts down a Perl variable and after it was 1409callback. The callback simply counts down a Perl variable and after it was
1181invoked "watcher" times, it would C<< ->broadcast >> a condvar once to 1410invoked "watcher" times, it would C<< ->send >> a condvar once to
1182signal the end of this phase. 1411signal the end of this phase.
1183 1412
1184I<destroy> is the time, in microseconds, that it takes to destroy a single 1413I<destroy> is the time, in microseconds, that it takes to destroy a single
1185watcher. 1414watcher.
1186 1415
1282 1511
1283=back 1512=back
1284 1513
1285=head2 BENCHMARKING THE LARGE SERVER CASE 1514=head2 BENCHMARKING THE LARGE SERVER CASE
1286 1515
1287This benchmark atcually benchmarks the event loop itself. It works by 1516This benchmark actually benchmarks the event loop itself. It works by
1288creating a number of "servers": each server consists of a socketpair, a 1517creating a number of "servers": each server consists of a socket pair, a
1289timeout watcher that gets reset on activity (but never fires), and an I/O 1518timeout watcher that gets reset on activity (but never fires), and an I/O
1290watcher waiting for input on one side of the socket. Each time the socket 1519watcher waiting for input on one side of the socket. Each time the socket
1291watcher reads a byte it will write that byte to a random other "server". 1520watcher reads a byte it will write that byte to a random other "server".
1292 1521
1293The effect is that there will be a lot of I/O watchers, only part of which 1522The effect is that there will be a lot of I/O watchers, only part of which
1294are active at any one point (so there is a constant number of active 1523are active at any one point (so there is a constant number of active
1295fds for each loop iterstaion, but which fds these are is random). The 1524fds for each loop iteration, but which fds these are is random). The
1296timeout is reset each time something is read because that reflects how 1525timeout is reset each time something is read because that reflects how
1297most timeouts work (and puts extra pressure on the event loops). 1526most timeouts work (and puts extra pressure on the event loops).
1298 1527
1299In this benchmark, we use 10000 socketpairs (20000 sockets), of which 100 1528In this benchmark, we use 10000 socket pairs (20000 sockets), of which 100
1300(1%) are active. This mirrors the activity of large servers with many 1529(1%) are active. This mirrors the activity of large servers with many
1301connections, most of which are idle at any one point in time. 1530connections, most of which are idle at any one point in time.
1302 1531
1303Source code for this benchmark is found as F<eg/bench2> in the AnyEvent 1532Source code for this benchmark is found as F<eg/bench2> in the AnyEvent
1304distribution. 1533distribution.
1306=head3 Explanation of the columns 1535=head3 Explanation of the columns
1307 1536
1308I<sockets> is the number of sockets, and twice the number of "servers" (as 1537I<sockets> is the number of sockets, and twice the number of "servers" (as
1309each server has a read and write socket end). 1538each server has a read and write socket end).
1310 1539
1311I<create> is the time it takes to create a socketpair (which is 1540I<create> is the time it takes to create a socket pair (which is
1312nontrivial) and two watchers: an I/O watcher and a timeout watcher. 1541nontrivial) and two watchers: an I/O watcher and a timeout watcher.
1313 1542
1314I<request>, the most important value, is the time it takes to handle a 1543I<request>, the most important value, is the time it takes to handle a
1315single "request", that is, reading the token from the pipe and forwarding 1544single "request", that is, reading the token from the pipe and forwarding
1316it to another server. This includes deleting the old timeout and creating 1545it to another server. This includes deleting the old timeout and creating
1389speed most when you have lots of watchers, not when you only have a few of 1618speed most when you have lots of watchers, not when you only have a few of
1390them). 1619them).
1391 1620
1392EV is again fastest. 1621EV is again fastest.
1393 1622
1394Perl again comes second. It is noticably faster than the C-based event 1623Perl again comes second. It is noticeably faster than the C-based event
1395loops Event and Glib, although the difference is too small to really 1624loops Event and Glib, although the difference is too small to really
1396matter. 1625matter.
1397 1626
1398POE also performs much better in this case, but is is still far behind the 1627POE also performs much better in this case, but is is still far behind the
1399others. 1628others.
1439probably even less useful to an attacker than PERL_ANYEVENT_MODEL). 1668probably even less useful to an attacker than PERL_ANYEVENT_MODEL).
1440 1669
1441 1670
1442=head1 SEE ALSO 1671=head1 SEE ALSO
1443 1672
1673Utility functions: L<AnyEvent::Util>.
1674
1444Event modules: L<EV>, L<EV::Glib>, L<Glib::EV>, L<Event>, L<Glib::Event>, 1675Event modules: L<EV>, L<EV::Glib>, L<Glib::EV>, L<Event>, L<Glib::Event>,
1445L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. 1676L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.
1446 1677
1447Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>, 1678Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,
1448L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>, 1679L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,
1449L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>, 1680L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,
1450L<AnyEvent::Impl::POE>. 1681L<AnyEvent::Impl::POE>.
1451 1682
1683Non-blocking file handles, sockets, TCP clients and
1684servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>.
1685
1686Asynchronous DNS: L<AnyEvent::DNS>.
1687
1452Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>, 1688Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>,
1453 1689
1454Nontrivial usage examples: L<Net::FCP>, L<Net::XMPP2>. 1690Nontrivial usage examples: L<Net::FCP>, L<Net::XMPP2>, L<AnyEvent::DNS>.
1455 1691
1456 1692
1457=head1 AUTHOR 1693=head1 AUTHOR
1458 1694
1459 Marc Lehmann <schmorp@schmorp.de> 1695 Marc Lehmann <schmorp@schmorp.de>

Diff Legend

Removed lines
+ Added lines
< Changed lines
> Changed lines