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7 7
8=head1 SYNOPSIS 8=head1 SYNOPSIS
9 9
10 use AnyEvent; 10 use AnyEvent;
11 11
12 # if you prefer function calls, look at the L<AE> manpage for 12 # if you prefer function calls, look at the AE manpage for
13 # an alternative API. 13 # an alternative API.
14 14
15 # file handle or descriptor readable 15 # file handle or descriptor readable
16 my $w = AnyEvent->io (fh => $fh, poll => "r", cb => sub { ... }); 16 my $w = AnyEvent->io (fh => $fh, poll => "r", cb => sub { ... });
17 17
18 # one-shot or repeating timers 18 # one-shot or repeating timers
19 my $w = AnyEvent->timer (after => $seconds, cb => sub { ... }); 19 my $w = AnyEvent->timer (after => $seconds, cb => sub { ... });
20 my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ... 20 my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ...);
21 21
22 print AnyEvent->now; # prints current event loop time 22 print AnyEvent->now; # prints current event loop time
23 print AnyEvent->time; # think Time::HiRes::time or simply CORE::time. 23 print AnyEvent->time; # think Time::HiRes::time or simply CORE::time.
24 24
25 # POSIX signal 25 # POSIX signal
46in a tutorial or some gentle introduction, have a look at the 46in a tutorial or some gentle introduction, have a look at the
47L<AnyEvent::Intro> manpage. 47L<AnyEvent::Intro> manpage.
48 48
49=head1 SUPPORT 49=head1 SUPPORT
50 50
51An FAQ document is available as L<AnyEvent::FAQ>.
52
51There is a mailinglist for discussing all things AnyEvent, and an IRC 53There also is a mailinglist for discussing all things AnyEvent, and an IRC
52channel, too. 54channel, too.
53 55
54See the AnyEvent project page at the B<Schmorpforge Ta-Sa Software 56See the AnyEvent project page at the B<Schmorpforge Ta-Sa Software
55Repository>, at L<http://anyevent.schmorp.de>, for more info. 57Repository>, at L<http://anyevent.schmorp.de>, for more info.
56 58
76module users into the same thing by forcing them to use the same event 78module users into the same thing by forcing them to use the same event
77model you use. 79model you use.
78 80
79For modules like POE or IO::Async (which is a total misnomer as it is 81For modules like POE or IO::Async (which is a total misnomer as it is
80actually doing all I/O I<synchronously>...), using them in your module is 82actually doing all I/O I<synchronously>...), using them in your module is
81like joining a cult: After you joined, you are dependent on them and you 83like joining a cult: After you join, you are dependent on them and you
82cannot use anything else, as they are simply incompatible to everything 84cannot use anything else, as they are simply incompatible to everything
83that isn't them. What's worse, all the potential users of your 85that isn't them. What's worse, all the potential users of your
84module are I<also> forced to use the same event loop you use. 86module are I<also> forced to use the same event loop you use.
85 87
86AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works 88AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works
87fine. AnyEvent + Tk works fine etc. etc. but none of these work together 89fine. AnyEvent + Tk works fine etc. etc. but none of these work together
88with the rest: POE + IO::Async? No go. Tk + Event? No go. Again: if 90with the rest: POE + EV? No go. Tk + Event? No go. Again: if your module
89your module uses one of those, every user of your module has to use it, 91uses one of those, every user of your module has to use it, too. But if
90too. But if your module uses AnyEvent, it works transparently with all 92your module uses AnyEvent, it works transparently with all event models it
91event models it supports (including stuff like IO::Async, as long as those 93supports (including stuff like IO::Async, as long as those use one of the
92use one of the supported event loops. It is trivial to add new event loops 94supported event loops. It is easy to add new event loops to AnyEvent, too,
93to AnyEvent, too, so it is future-proof). 95so it is future-proof).
94 96
95In addition to being free of having to use I<the one and only true event 97In addition to being free of having to use I<the one and only true event
96model>, AnyEvent also is free of bloat and policy: with POE or similar 98model>, AnyEvent also is free of bloat and policy: with POE or similar
97modules, you get an enormous amount of code and strict rules you have to 99modules, you get an enormous amount of code and strict rules you have to
98follow. AnyEvent, on the other hand, is lean and up to the point, by only 100follow. AnyEvent, on the other hand, is lean and to the point, by only
99offering the functionality that is necessary, in as thin as a wrapper as 101offering the functionality that is necessary, in as thin as a wrapper as
100technically possible. 102technically possible.
101 103
102Of course, AnyEvent comes with a big (and fully optional!) toolbox 104Of course, AnyEvent comes with a big (and fully optional!) toolbox
103of useful functionality, such as an asynchronous DNS resolver, 100% 105of useful functionality, such as an asynchronous DNS resolver, 100%
109useful) and you want to force your users to use the one and only event 111useful) and you want to force your users to use the one and only event
110model, you should I<not> use this module. 112model, you should I<not> use this module.
111 113
112=head1 DESCRIPTION 114=head1 DESCRIPTION
113 115
114L<AnyEvent> provides an identical interface to multiple event loops. This 116L<AnyEvent> provides a uniform interface to various event loops. This
115allows module authors to utilise an event loop without forcing module 117allows module authors to use event loop functionality without forcing
116users to use the same event loop (as only a single event loop can coexist 118module users to use a specific event loop implementation (since more
117peacefully at any one time). 119than one event loop cannot coexist peacefully).
118 120
119The interface itself is vaguely similar, but not identical to the L<Event> 121The interface itself is vaguely similar, but not identical to the L<Event>
120module. 122module.
121 123
122During the first call of any watcher-creation method, the module tries 124During the first call of any watcher-creation method, the module tries
123to detect the currently loaded event loop by probing whether one of the 125to detect the currently loaded event loop by probing whether one of the
124following modules is already loaded: L<EV>, 126following modules is already loaded: L<EV>, L<AnyEvent::Loop>,
125L<Event>, L<Glib>, L<AnyEvent::Impl::Perl>, L<Tk>, L<Event::Lib>, L<Qt>, 127L<Event>, L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. The first one
126L<POE>. The first one found is used. If none are found, the module tries 128found is used. If none are detected, the module tries to load the first
127to load these modules (excluding Tk, Event::Lib, Qt and POE as the pure perl 129four modules in the order given; but note that if L<EV> is not
128adaptor should always succeed) in the order given. The first one that can 130available, the pure-perl L<AnyEvent::Loop> should always work, so
129be successfully loaded will be used. If, after this, still none could be 131the other two are not normally tried.
130found, AnyEvent will fall back to a pure-perl event loop, which is not
131very efficient, but should work everywhere.
132 132
133Because AnyEvent first checks for modules that are already loaded, loading 133Because AnyEvent first checks for modules that are already loaded, loading
134an event model explicitly before first using AnyEvent will likely make 134an event model explicitly before first using AnyEvent will likely make
135that model the default. For example: 135that model the default. For example:
136 136
138 use AnyEvent; 138 use AnyEvent;
139 139
140 # .. AnyEvent will likely default to Tk 140 # .. AnyEvent will likely default to Tk
141 141
142The I<likely> means that, if any module loads another event model and 142The I<likely> means that, if any module loads another event model and
143starts using it, all bets are off. Maybe you should tell their authors to 143starts using it, all bets are off - this case should be very rare though,
144use AnyEvent so their modules work together with others seamlessly... 144as very few modules hardcode event loops without announcing this very
145loudly.
145 146
146The pure-perl implementation of AnyEvent is called 147The pure-perl implementation of AnyEvent is called C<AnyEvent::Loop>. Like
147C<AnyEvent::Impl::Perl>. Like other event modules you can load it 148other event modules you can load it explicitly and enjoy the high
148explicitly and enjoy the high availability of that event loop :) 149availability of that event loop :)
149 150
150=head1 WATCHERS 151=head1 WATCHERS
151 152
152AnyEvent has the central concept of a I<watcher>, which is an object that 153AnyEvent has the central concept of a I<watcher>, which is an object that
153stores relevant data for each kind of event you are waiting for, such as 154stores relevant data for each kind of event you are waiting for, such as
158callback when the event occurs (of course, only when the event model 159callback when the event occurs (of course, only when the event model
159is in control). 160is in control).
160 161
161Note that B<callbacks must not permanently change global variables> 162Note that B<callbacks must not permanently change global variables>
162potentially in use by the event loop (such as C<$_> or C<$[>) and that B<< 163potentially in use by the event loop (such as C<$_> or C<$[>) and that B<<
163callbacks must not C<die> >>. The former is good programming practise in 164callbacks must not C<die> >>. The former is good programming practice in
164Perl and the latter stems from the fact that exception handling differs 165Perl and the latter stems from the fact that exception handling differs
165widely between event loops. 166widely between event loops.
166 167
167To disable the watcher you have to destroy it (e.g. by setting the 168To disable a watcher you have to destroy it (e.g. by setting the
168variable you store it in to C<undef> or otherwise deleting all references 169variable you store it in to C<undef> or otherwise deleting all references
169to it). 170to it).
170 171
171All watchers are created by calling a method on the C<AnyEvent> class. 172All watchers are created by calling a method on the C<AnyEvent> class.
172 173
173Many watchers either are used with "recursion" (repeating timers for 174Many watchers either are used with "recursion" (repeating timers for
174example), or need to refer to their watcher object in other ways. 175example), or need to refer to their watcher object in other ways.
175 176
176An any way to achieve that is this pattern: 177One way to achieve that is this pattern:
177 178
178 my $w; $w = AnyEvent->type (arg => value ..., cb => sub { 179 my $w; $w = AnyEvent->type (arg => value ..., cb => sub {
179 # you can use $w here, for example to undef it 180 # you can use $w here, for example to undef it
180 undef $w; 181 undef $w;
181 }); 182 });
213 214
214The I/O watcher might use the underlying file descriptor or a copy of it. 215The I/O watcher might use the underlying file descriptor or a copy of it.
215You must not close a file handle as long as any watcher is active on the 216You must not close a file handle as long as any watcher is active on the
216underlying file descriptor. 217underlying file descriptor.
217 218
218Some event loops issue spurious readyness notifications, so you should 219Some event loops issue spurious readiness notifications, so you should
219always use non-blocking calls when reading/writing from/to your file 220always use non-blocking calls when reading/writing from/to your file
220handles. 221handles.
221 222
222Example: wait for readability of STDIN, then read a line and disable the 223Example: wait for readability of STDIN, then read a line and disable the
223watcher. 224watcher.
247 248
248Although the callback might get passed parameters, their value and 249Although the callback might get passed parameters, their value and
249presence is undefined and you cannot rely on them. Portable AnyEvent 250presence is undefined and you cannot rely on them. Portable AnyEvent
250callbacks cannot use arguments passed to time watcher callbacks. 251callbacks cannot use arguments passed to time watcher callbacks.
251 252
252The callback will normally be invoked once only. If you specify another 253The callback will normally be invoked only once. If you specify another
253parameter, C<interval>, as a strictly positive number (> 0), then the 254parameter, C<interval>, as a strictly positive number (> 0), then the
254callback will be invoked regularly at that interval (in fractional 255callback will be invoked regularly at that interval (in fractional
255seconds) after the first invocation. If C<interval> is specified with a 256seconds) after the first invocation. If C<interval> is specified with a
256false value, then it is treated as if it were missing. 257false value, then it is treated as if it were not specified at all.
257 258
258The callback will be rescheduled before invoking the callback, but no 259The callback will be rescheduled before invoking the callback, but no
259attempt is done to avoid timer drift in most backends, so the interval is 260attempt is made to avoid timer drift in most backends, so the interval is
260only approximate. 261only approximate.
261 262
262Example: fire an event after 7.7 seconds. 263Example: fire an event after 7.7 seconds.
263 264
264 my $w = AnyEvent->timer (after => 7.7, cb => sub { 265 my $w = AnyEvent->timer (after => 7.7, cb => sub {
282 283
283While most event loops expect timers to specified in a relative way, they 284While most event loops expect timers to specified in a relative way, they
284use absolute time internally. This makes a difference when your clock 285use absolute time internally. This makes a difference when your clock
285"jumps", for example, when ntp decides to set your clock backwards from 286"jumps", for example, when ntp decides to set your clock backwards from
286the wrong date of 2014-01-01 to 2008-01-01, a watcher that is supposed to 287the wrong date of 2014-01-01 to 2008-01-01, a watcher that is supposed to
287fire "after" a second might actually take six years to finally fire. 288fire "after a second" might actually take six years to finally fire.
288 289
289AnyEvent cannot compensate for this. The only event loop that is conscious 290AnyEvent cannot compensate for this. The only event loop that is conscious
290about these issues is L<EV>, which offers both relative (ev_timer, based 291of these issues is L<EV>, which offers both relative (ev_timer, based
291on true relative time) and absolute (ev_periodic, based on wallclock time) 292on true relative time) and absolute (ev_periodic, based on wallclock time)
292timers. 293timers.
293 294
294AnyEvent always prefers relative timers, if available, matching the 295AnyEvent always prefers relative timers, if available, matching the
295AnyEvent API. 296AnyEvent API.
317I<In almost all cases (in all cases if you don't care), this is the 318I<In almost all cases (in all cases if you don't care), this is the
318function to call when you want to know the current time.> 319function to call when you want to know the current time.>
319 320
320This function is also often faster then C<< AnyEvent->time >>, and 321This function is also often faster then C<< AnyEvent->time >>, and
321thus the preferred method if you want some timestamp (for example, 322thus the preferred method if you want some timestamp (for example,
322L<AnyEvent::Handle> uses this to update it's activity timeouts). 323L<AnyEvent::Handle> uses this to update its activity timeouts).
323 324
324The rest of this section is only of relevance if you try to be very exact 325The rest of this section is only of relevance if you try to be very exact
325with your timing, you can skip it without bad conscience. 326with your timing; you can skip it without a bad conscience.
326 327
327For a practical example of when these times differ, consider L<Event::Lib> 328For a practical example of when these times differ, consider L<Event::Lib>
328and L<EV> and the following set-up: 329and L<EV> and the following set-up:
329 330
330The event loop is running and has just invoked one of your callback at 331The event loop is running and has just invoked one of your callbacks at
331time=500 (assume no other callbacks delay processing). In your callback, 332time=500 (assume no other callbacks delay processing). In your callback,
332you wait a second by executing C<sleep 1> (blocking the process for a 333you wait a second by executing C<sleep 1> (blocking the process for a
333second) and then (at time=501) you create a relative timer that fires 334second) and then (at time=501) you create a relative timer that fires
334after three seconds. 335after three seconds.
335 336
355difference between C<< AnyEvent->time >> and C<< AnyEvent->now >> into 356difference between C<< AnyEvent->time >> and C<< AnyEvent->now >> into
356account. 357account.
357 358
358=item AnyEvent->now_update 359=item AnyEvent->now_update
359 360
360Some event loops (such as L<EV> or L<AnyEvent::Impl::Perl>) cache 361Some event loops (such as L<EV> or L<AnyEvent::Loop>) cache the current
361the current time for each loop iteration (see the discussion of L<< 362time for each loop iteration (see the discussion of L<< AnyEvent->now >>,
362AnyEvent->now >>, above). 363above).
363 364
364When a callback runs for a long time (or when the process sleeps), then 365When a callback runs for a long time (or when the process sleeps), then
365this "current" time will differ substantially from the real time, which 366this "current" time will differ substantially from the real time, which
366might affect timers and time-outs. 367might affect timers and time-outs.
367 368
428=head3 Signal Races, Delays and Workarounds 429=head3 Signal Races, Delays and Workarounds
429 430
430Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching 431Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching
431callbacks to signals in a generic way, which is a pity, as you cannot 432callbacks to signals in a generic way, which is a pity, as you cannot
432do race-free signal handling in perl, requiring C libraries for 433do race-free signal handling in perl, requiring C libraries for
433this. AnyEvent will try to do it's best, which means in some cases, 434this. AnyEvent will try to do its best, which means in some cases,
434signals will be delayed. The maximum time a signal might be delayed is 435signals will be delayed. The maximum time a signal might be delayed is
435specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This 436specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This
436variable can be changed only before the first signal watcher is created, 437variable can be changed only before the first signal watcher is created,
437and should be left alone otherwise. This variable determines how often 438and should be left alone otherwise. This variable determines how often
438AnyEvent polls for signals (in case a wake-up was missed). Higher values 439AnyEvent polls for signals (in case a wake-up was missed). Higher values
440saving. 441saving.
441 442
442All these problems can be avoided by installing the optional 443All these problems can be avoided by installing the optional
443L<Async::Interrupt> module, which works with most event loops. It will not 444L<Async::Interrupt> module, which works with most event loops. It will not
444work with inherently broken event loops such as L<Event> or L<Event::Lib> 445work with inherently broken event loops such as L<Event> or L<Event::Lib>
445(and not with L<POE> currently, as POE does it's own workaround with 446(and not with L<POE> currently, as POE does its own workaround with
446one-second latency). For those, you just have to suffer the delays. 447one-second latency). For those, you just have to suffer the delays.
447 448
448=head2 CHILD PROCESS WATCHERS 449=head2 CHILD PROCESS WATCHERS
449 450
450 $w = AnyEvent->child (pid => <process id>, cb => <callback>); 451 $w = AnyEvent->child (pid => <process id>, cb => <callback>);
451 452
452You can also watch on a child process exit and catch its exit status. 453You can also watch for a child process exit and catch its exit status.
453 454
454The child process is specified by the C<pid> argument (one some backends, 455The child process is specified by the C<pid> argument (on some backends,
455using C<0> watches for any child process exit, on others this will 456using C<0> watches for any child process exit, on others this will
456croak). The watcher will be triggered only when the child process has 457croak). The watcher will be triggered only when the child process has
457finished and an exit status is available, not on any trace events 458finished and an exit status is available, not on any trace events
458(stopped/continued). 459(stopped/continued).
459 460
481thing in an AnyEvent program, you I<have> to create at least one 482thing in an AnyEvent program, you I<have> to create at least one
482watcher before you C<fork> the child (alternatively, you can call 483watcher before you C<fork> the child (alternatively, you can call
483C<AnyEvent::detect>). 484C<AnyEvent::detect>).
484 485
485As most event loops do not support waiting for child events, they will be 486As most event loops do not support waiting for child events, they will be
486emulated by AnyEvent in most cases, in which the latency and race problems 487emulated by AnyEvent in most cases, in which case the latency and race
487mentioned in the description of signal watchers apply. 488problems mentioned in the description of signal watchers apply.
488 489
489Example: fork a process and wait for it 490Example: fork a process and wait for it
490 491
491 my $done = AnyEvent->condvar; 492 my $done = AnyEvent->condvar;
492 493
506 507
507=head2 IDLE WATCHERS 508=head2 IDLE WATCHERS
508 509
509 $w = AnyEvent->idle (cb => <callback>); 510 $w = AnyEvent->idle (cb => <callback>);
510 511
511Repeatedly invoke the callback after the process becomes idle, until 512This will repeatedly invoke the callback after the process becomes idle,
512either the watcher is destroyed or new events have been detected. 513until either the watcher is destroyed or new events have been detected.
513 514
514Idle watchers are useful when there is a need to do something, but it 515Idle watchers are useful when there is a need to do something, but it
515is not so important (or wise) to do it instantly. The callback will be 516is not so important (or wise) to do it instantly. The callback will be
516invoked only when there is "nothing better to do", which is usually 517invoked only when there is "nothing better to do", which is usually
517defined as "all outstanding events have been handled and no new events 518defined as "all outstanding events have been handled and no new events
556will actively watch for new events and call your callbacks. 557will actively watch for new events and call your callbacks.
557 558
558AnyEvent is slightly different: it expects somebody else to run the event 559AnyEvent is slightly different: it expects somebody else to run the event
559loop and will only block when necessary (usually when told by the user). 560loop and will only block when necessary (usually when told by the user).
560 561
561The instrument to do that is called a "condition variable", so called 562The tool to do that is called a "condition variable", so called because
562because they represent a condition that must become true. 563they represent a condition that must become true.
563 564
564Now is probably a good time to look at the examples further below. 565Now is probably a good time to look at the examples further below.
565 566
566Condition variables can be created by calling the C<< AnyEvent->condvar 567Condition variables can be created by calling the C<< AnyEvent->condvar
567>> method, usually without arguments. The only argument pair allowed is 568>> method, usually without arguments. The only argument pair allowed is
572After creation, the condition variable is "false" until it becomes "true" 573After creation, the condition variable is "false" until it becomes "true"
573by calling the C<send> method (or calling the condition variable as if it 574by calling the C<send> method (or calling the condition variable as if it
574were a callback, read about the caveats in the description for the C<< 575were a callback, read about the caveats in the description for the C<<
575->send >> method). 576->send >> method).
576 577
577Condition variables are similar to callbacks, except that you can 578Since condition variables are the most complex part of the AnyEvent API, here are
578optionally wait for them. They can also be called merge points - points 579some different mental models of what they are - pick the ones you can connect to:
579in time where multiple outstanding events have been processed. And yet 580
580another way to call them is transactions - each condition variable can be 581=over 4
581used to represent a transaction, which finishes at some point and delivers 582
582a result. And yet some people know them as "futures" - a promise to 583=item * Condition variables are like callbacks - you can call them (and pass them instead
583compute/deliver something that you can wait for. 584of callbacks). Unlike callbacks however, you can also wait for them to be called.
585
586=item * Condition variables are signals - one side can emit or send them,
587the other side can wait for them, or install a handler that is called when
588the signal fires.
589
590=item * Condition variables are like "Merge Points" - points in your program
591where you merge multiple independent results/control flows into one.
592
593=item * Condition variables represent a transaction - functions that start
594some kind of transaction can return them, leaving the caller the choice
595between waiting in a blocking fashion, or setting a callback.
596
597=item * Condition variables represent future values, or promises to deliver
598some result, long before the result is available.
599
600=back
584 601
585Condition variables are very useful to signal that something has finished, 602Condition variables are very useful to signal that something has finished,
586for example, if you write a module that does asynchronous http requests, 603for example, if you write a module that does asynchronous http requests,
587then a condition variable would be the ideal candidate to signal the 604then a condition variable would be the ideal candidate to signal the
588availability of results. The user can either act when the callback is 605availability of results. The user can either act when the callback is
601 618
602Condition variables are represented by hash refs in perl, and the keys 619Condition variables are represented by hash refs in perl, and the keys
603used by AnyEvent itself are all named C<_ae_XXX> to make subclassing 620used by AnyEvent itself are all named C<_ae_XXX> to make subclassing
604easy (it is often useful to build your own transaction class on top of 621easy (it is often useful to build your own transaction class on top of
605AnyEvent). To subclass, use C<AnyEvent::CondVar> as base class and call 622AnyEvent). To subclass, use C<AnyEvent::CondVar> as base class and call
606it's C<new> method in your own C<new> method. 623its C<new> method in your own C<new> method.
607 624
608There are two "sides" to a condition variable - the "producer side" which 625There are two "sides" to a condition variable - the "producer side" which
609eventually calls C<< -> send >>, and the "consumer side", which waits 626eventually calls C<< -> send >>, and the "consumer side", which waits
610for the send to occur. 627for the send to occur.
611 628
676they were a code reference). Calling them directly is the same as calling 693they were a code reference). Calling them directly is the same as calling
677C<send>. 694C<send>.
678 695
679=item $cv->croak ($error) 696=item $cv->croak ($error)
680 697
681Similar to send, but causes all call's to C<< ->recv >> to invoke 698Similar to send, but causes all calls to C<< ->recv >> to invoke
682C<Carp::croak> with the given error message/object/scalar. 699C<Carp::croak> with the given error message/object/scalar.
683 700
684This can be used to signal any errors to the condition variable 701This can be used to signal any errors to the condition variable
685user/consumer. Doing it this way instead of calling C<croak> directly 702user/consumer. Doing it this way instead of calling C<croak> directly
686delays the error detetcion, but has the overwhelmign advantage that it 703delays the error detection, but has the overwhelming advantage that it
687diagnoses the error at the place where the result is expected, and not 704diagnoses the error at the place where the result is expected, and not
688deep in some event clalback without connection to the actual code causing 705deep in some event callback with no connection to the actual code causing
689the problem. 706the problem.
690 707
691=item $cv->begin ([group callback]) 708=item $cv->begin ([group callback])
692 709
693=item $cv->end 710=item $cv->end
731one call to C<begin>, so the condvar waits for all calls to C<end> before 748one call to C<begin>, so the condvar waits for all calls to C<end> before
732sending. 749sending.
733 750
734The ping example mentioned above is slightly more complicated, as the 751The ping example mentioned above is slightly more complicated, as the
735there are results to be passwd back, and the number of tasks that are 752there are results to be passwd back, and the number of tasks that are
736begung can potentially be zero: 753begun can potentially be zero:
737 754
738 my $cv = AnyEvent->condvar; 755 my $cv = AnyEvent->condvar;
739 756
740 my %result; 757 my %result;
741 $cv->begin (sub { shift->send (\%result) }); 758 $cv->begin (sub { shift->send (\%result) });
762to be called once the counter reaches C<0>, and second, it ensures that 779to be called once the counter reaches C<0>, and second, it ensures that
763C<send> is called even when C<no> hosts are being pinged (the loop 780C<send> is called even when C<no> hosts are being pinged (the loop
764doesn't execute once). 781doesn't execute once).
765 782
766This is the general pattern when you "fan out" into multiple (but 783This is the general pattern when you "fan out" into multiple (but
767potentially none) subrequests: use an outer C<begin>/C<end> pair to set 784potentially zero) subrequests: use an outer C<begin>/C<end> pair to set
768the callback and ensure C<end> is called at least once, and then, for each 785the callback and ensure C<end> is called at least once, and then, for each
769subrequest you start, call C<begin> and for each subrequest you finish, 786subrequest you start, call C<begin> and for each subrequest you finish,
770call C<end>. 787call C<end>.
771 788
772=back 789=back
779=over 4 796=over 4
780 797
781=item $cv->recv 798=item $cv->recv
782 799
783Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak 800Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak
784>> methods have been called on c<$cv>, while servicing other watchers 801>> methods have been called on C<$cv>, while servicing other watchers
785normally. 802normally.
786 803
787You can only wait once on a condition - additional calls are valid but 804You can only wait once on a condition - additional calls are valid but
788will return immediately. 805will return immediately.
789 806
806caller decide whether the call will block or not (for example, by coupling 823caller decide whether the call will block or not (for example, by coupling
807condition variables with some kind of request results and supporting 824condition variables with some kind of request results and supporting
808callbacks so the caller knows that getting the result will not block, 825callbacks so the caller knows that getting the result will not block,
809while still supporting blocking waits if the caller so desires). 826while still supporting blocking waits if the caller so desires).
810 827
811You can ensure that C<< -recv >> never blocks by setting a callback and 828You can ensure that C<< ->recv >> never blocks by setting a callback and
812only calling C<< ->recv >> from within that callback (or at a later 829only calling C<< ->recv >> from within that callback (or at a later
813time). This will work even when the event loop does not support blocking 830time). This will work even when the event loop does not support blocking
814waits otherwise. 831waits otherwise.
815 832
816=item $bool = $cv->ready 833=item $bool = $cv->ready
821=item $cb = $cv->cb ($cb->($cv)) 838=item $cb = $cv->cb ($cb->($cv))
822 839
823This is a mutator function that returns the callback set and optionally 840This is a mutator function that returns the callback set and optionally
824replaces it before doing so. 841replaces it before doing so.
825 842
826The callback will be called when the condition becomes (or already was) 843The callback will be called when the condition becomes "true", i.e. when
827"true", i.e. when C<send> or C<croak> are called (or were called), with 844C<send> or C<croak> are called, with the only argument being the
828the only argument being the condition variable itself. Calling C<recv> 845condition variable itself. If the condition is already true, the
846callback is called immediately when it is set. Calling C<recv> inside
829inside the callback or at any later time is guaranteed not to block. 847the callback or at any later time is guaranteed not to block.
830 848
831=back 849=back
832 850
833=head1 SUPPORTED EVENT LOOPS/BACKENDS 851=head1 SUPPORTED EVENT LOOPS/BACKENDS
834 852
842use. If EV is not installed, then AnyEvent will fall back to its own 860use. If EV is not installed, then AnyEvent will fall back to its own
843pure-perl implementation, which is available everywhere as it comes with 861pure-perl implementation, which is available everywhere as it comes with
844AnyEvent itself. 862AnyEvent itself.
845 863
846 AnyEvent::Impl::EV based on EV (interface to libev, best choice). 864 AnyEvent::Impl::EV based on EV (interface to libev, best choice).
847 AnyEvent::Impl::Perl pure-perl implementation, fast and portable. 865 AnyEvent::Impl::Perl pure-perl AnyEvent::Loop, fast and portable.
848 866
849=item Backends that are transparently being picked up when they are used. 867=item Backends that are transparently being picked up when they are used.
850 868
851These will be used when they are currently loaded when the first watcher 869These will be used if they are already loaded when the first watcher
852is created, in which case it is assumed that the application is using 870is created, in which case it is assumed that the application is using
853them. This means that AnyEvent will automatically pick the right backend 871them. This means that AnyEvent will automatically pick the right backend
854when the main program loads an event module before anything starts to 872when the main program loads an event module before anything starts to
855create watchers. Nothing special needs to be done by the main program. 873create watchers. Nothing special needs to be done by the main program.
856 874
858 AnyEvent::Impl::Glib based on Glib, slow but very stable. 876 AnyEvent::Impl::Glib based on Glib, slow but very stable.
859 AnyEvent::Impl::Tk based on Tk, very broken. 877 AnyEvent::Impl::Tk based on Tk, very broken.
860 AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. 878 AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
861 AnyEvent::Impl::POE based on POE, very slow, some limitations. 879 AnyEvent::Impl::POE based on POE, very slow, some limitations.
862 AnyEvent::Impl::Irssi used when running within irssi. 880 AnyEvent::Impl::Irssi used when running within irssi.
881 AnyEvent::Impl::IOAsync based on IO::Async.
882 AnyEvent::Impl::Cocoa based on Cocoa::EventLoop.
883 AnyEvent::Impl::FLTK based on FLTK.
863 884
864=item Backends with special needs. 885=item Backends with special needs.
865 886
866Qt requires the Qt::Application to be instantiated first, but will 887Qt requires the Qt::Application to be instantiated first, but will
867otherwise be picked up automatically. As long as the main program 888otherwise be picked up automatically. As long as the main program
868instantiates the application before any AnyEvent watchers are created, 889instantiates the application before any AnyEvent watchers are created,
869everything should just work. 890everything should just work.
870 891
871 AnyEvent::Impl::Qt based on Qt. 892 AnyEvent::Impl::Qt based on Qt.
872 893
873Support for IO::Async can only be partial, as it is too broken and
874architecturally limited to even support the AnyEvent API. It also
875is the only event loop that needs the loop to be set explicitly, so
876it can only be used by a main program knowing about AnyEvent. See
877L<AnyEvent::Impl::Async> for the gory details.
878
879 AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed.
880
881=item Event loops that are indirectly supported via other backends. 894=item Event loops that are indirectly supported via other backends.
882 895
883Some event loops can be supported via other modules: 896Some event loops can be supported via other modules:
884 897
885There is no direct support for WxWidgets (L<Wx>) or L<Prima>. 898There is no direct support for WxWidgets (L<Wx>) or L<Prima>.
910Contains C<undef> until the first watcher is being created, before the 923Contains C<undef> until the first watcher is being created, before the
911backend has been autodetected. 924backend has been autodetected.
912 925
913Afterwards it contains the event model that is being used, which is the 926Afterwards it contains the event model that is being used, which is the
914name of the Perl class implementing the model. This class is usually one 927name of the Perl class implementing the model. This class is usually one
915of the C<AnyEvent::Impl:xxx> modules, but can be any other class in the 928of the C<AnyEvent::Impl::xxx> modules, but can be any other class in the
916case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it 929case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it
917will be C<urxvt::anyevent>). 930will be C<urxvt::anyevent>).
918 931
919=item AnyEvent::detect 932=item AnyEvent::detect
920 933
921Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model 934Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model
922if necessary. You should only call this function right before you would 935if necessary. You should only call this function right before you would
923have created an AnyEvent watcher anyway, that is, as late as possible at 936have created an AnyEvent watcher anyway, that is, as late as possible at
924runtime, and not e.g. while initialising of your module. 937runtime, and not e.g. during initialisation of your module.
925 938
926If you need to do some initialisation before AnyEvent watchers are 939If you need to do some initialisation before AnyEvent watchers are
927created, use C<post_detect>. 940created, use C<post_detect>.
928 941
929=item $guard = AnyEvent::post_detect { BLOCK } 942=item $guard = AnyEvent::post_detect { BLOCK }
930 943
931Arranges for the code block to be executed as soon as the event model is 944Arranges for the code block to be executed as soon as the event model is
932autodetected (or immediately if this has already happened). 945autodetected (or immediately if that has already happened).
933 946
934The block will be executed I<after> the actual backend has been detected 947The block will be executed I<after> the actual backend has been detected
935(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been 948(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been
936created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do 949created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do
937other initialisations - see the sources of L<AnyEvent::Strict> or 950other initialisations - see the sources of L<AnyEvent::Strict> or
946that automatically removes the callback again when it is destroyed (or 959that automatically removes the callback again when it is destroyed (or
947C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for 960C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for
948a case where this is useful. 961a case where this is useful.
949 962
950Example: Create a watcher for the IO::AIO module and store it in 963Example: Create a watcher for the IO::AIO module and store it in
951C<$WATCHER>. Only do so after the event loop is initialised, though. 964C<$WATCHER>, but do so only do so after the event loop is initialised.
952 965
953 our WATCHER; 966 our WATCHER;
954 967
955 my $guard = AnyEvent::post_detect { 968 my $guard = AnyEvent::post_detect {
956 $WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb); 969 $WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb);
964 $WATCHER ||= $guard; 977 $WATCHER ||= $guard;
965 978
966=item @AnyEvent::post_detect 979=item @AnyEvent::post_detect
967 980
968If there are any code references in this array (you can C<push> to it 981If there are any code references in this array (you can C<push> to it
969before or after loading AnyEvent), then they will called directly after 982before or after loading AnyEvent), then they will be called directly
970the event loop has been chosen. 983after the event loop has been chosen.
971 984
972You should check C<$AnyEvent::MODEL> before adding to this array, though: 985You should check C<$AnyEvent::MODEL> before adding to this array, though:
973if it is defined then the event loop has already been detected, and the 986if it is defined then the event loop has already been detected, and the
974array will be ignored. 987array will be ignored.
975 988
1011because it will stall the whole program, and the whole point of using 1024because it will stall the whole program, and the whole point of using
1012events is to stay interactive. 1025events is to stay interactive.
1013 1026
1014It is fine, however, to call C<< ->recv >> when the user of your module 1027It is fine, however, to call C<< ->recv >> when the user of your module
1015requests it (i.e. if you create a http request object ad have a method 1028requests it (i.e. if you create a http request object ad have a method
1016called C<results> that returns the results, it should call C<< ->recv >> 1029called C<results> that returns the results, it may call C<< ->recv >>
1017freely, as the user of your module knows what she is doing. always). 1030freely, as the user of your module knows what she is doing. Always).
1018 1031
1019=head1 WHAT TO DO IN THE MAIN PROGRAM 1032=head1 WHAT TO DO IN THE MAIN PROGRAM
1020 1033
1021There will always be a single main program - the only place that should 1034There will always be a single main program - the only place that should
1022dictate which event model to use. 1035dictate which event model to use.
1023 1036
1024If it doesn't care, it can just "use AnyEvent" and use it itself, or not 1037If the program is not event-based, it need not do anything special, even
1025do anything special (it does not need to be event-based) and let AnyEvent 1038when it depends on a module that uses an AnyEvent. If the program itself
1026decide which implementation to chose if some module relies on it. 1039uses AnyEvent, but does not care which event loop is used, all it needs
1040to do is C<use AnyEvent>. In either case, AnyEvent will choose the best
1041available loop implementation.
1027 1042
1028If the main program relies on a specific event model - for example, in 1043If the main program relies on a specific event model - for example, in
1029Gtk2 programs you have to rely on the Glib module - you should load the 1044Gtk2 programs you have to rely on the Glib module - you should load the
1030event module before loading AnyEvent or any module that uses it: generally 1045event module before loading AnyEvent or any module that uses it: generally
1031speaking, you should load it as early as possible. The reason is that 1046speaking, you should load it as early as possible. The reason is that
1032modules might create watchers when they are loaded, and AnyEvent will 1047modules might create watchers when they are loaded, and AnyEvent will
1033decide on the event model to use as soon as it creates watchers, and it 1048decide on the event model to use as soon as it creates watchers, and it
1034might chose the wrong one unless you load the correct one yourself. 1049might choose the wrong one unless you load the correct one yourself.
1035 1050
1036You can chose to use a pure-perl implementation by loading the 1051You can chose to use a pure-perl implementation by loading the
1037C<AnyEvent::Impl::Perl> module, which gives you similar behaviour 1052C<AnyEvent::Loop> module, which gives you similar behaviour
1038everywhere, but letting AnyEvent chose the model is generally better. 1053everywhere, but letting AnyEvent chose the model is generally better.
1039 1054
1040=head2 MAINLOOP EMULATION 1055=head2 MAINLOOP EMULATION
1041 1056
1042Sometimes (often for short test scripts, or even standalone programs who 1057Sometimes (often for short test scripts, or even standalone programs who
1057=head1 OTHER MODULES 1072=head1 OTHER MODULES
1058 1073
1059The following is a non-exhaustive list of additional modules that use 1074The following is a non-exhaustive list of additional modules that use
1060AnyEvent as a client and can therefore be mixed easily with other AnyEvent 1075AnyEvent as a client and can therefore be mixed easily with other AnyEvent
1061modules and other event loops in the same program. Some of the modules 1076modules and other event loops in the same program. Some of the modules
1062come with AnyEvent, most are available via CPAN. 1077come as part of AnyEvent, the others are available via CPAN.
1063 1078
1064=over 4 1079=over 4
1065 1080
1066=item L<AnyEvent::Util> 1081=item L<AnyEvent::Util>
1067 1082
1068Contains various utility functions that replace often-used but blocking 1083Contains various utility functions that replace often-used blocking
1069functions such as C<inet_aton> by event-/callback-based versions. 1084functions such as C<inet_aton> with event/callback-based versions.
1070 1085
1071=item L<AnyEvent::Socket> 1086=item L<AnyEvent::Socket>
1072 1087
1073Provides various utility functions for (internet protocol) sockets, 1088Provides various utility functions for (internet protocol) sockets,
1074addresses and name resolution. Also functions to create non-blocking tcp 1089addresses and name resolution. Also functions to create non-blocking tcp
1076 1091
1077=item L<AnyEvent::Handle> 1092=item L<AnyEvent::Handle>
1078 1093
1079Provide read and write buffers, manages watchers for reads and writes, 1094Provide read and write buffers, manages watchers for reads and writes,
1080supports raw and formatted I/O, I/O queued and fully transparent and 1095supports raw and formatted I/O, I/O queued and fully transparent and
1081non-blocking SSL/TLS (via L<AnyEvent::TLS>. 1096non-blocking SSL/TLS (via L<AnyEvent::TLS>).
1082 1097
1083=item L<AnyEvent::DNS> 1098=item L<AnyEvent::DNS>
1084 1099
1085Provides rich asynchronous DNS resolver capabilities. 1100Provides rich asynchronous DNS resolver capabilities.
1086 1101
1102=item L<AnyEvent::HTTP>, L<AnyEvent::IRC>, L<AnyEvent::XMPP>, L<AnyEvent::GPSD>, L<AnyEvent::IGS>, L<AnyEvent::FCP>
1103
1104Implement event-based interfaces to the protocols of the same name (for
1105the curious, IGS is the International Go Server and FCP is the Freenet
1106Client Protocol).
1107
1108=item L<AnyEvent::Handle::UDP>
1109
1110Here be danger!
1111
1112As Pauli would put it, "Not only is it not right, it's not even wrong!" -
1113there are so many things wrong with AnyEvent::Handle::UDP, most notably
1114its use of a stream-based API with a protocol that isn't streamable, that
1115the only way to improve it is to delete it.
1116
1117It features data corruption (but typically only under load) and general
1118confusion. On top, the author is not only clueless about UDP but also
1119fact-resistant - some gems of his understanding: "connect doesn't work
1120with UDP", "UDP packets are not IP packets", "UDP only has datagrams, not
1121packets", "I don't need to implement proper error checking as UDP doesn't
1122support error checking" and so on - he doesn't even understand what's
1123wrong with his module when it is explained to him.
1124
1087=item L<AnyEvent::HTTP> 1125=item L<AnyEvent::DBI>
1088 1126
1089A simple-to-use HTTP library that is capable of making a lot of concurrent 1127Executes L<DBI> requests asynchronously in a proxy process for you,
1090HTTP requests. 1128notifying you in an event-based way when the operation is finished.
1129
1130=item L<AnyEvent::AIO>
1131
1132Truly asynchronous (as opposed to non-blocking) I/O, should be in the
1133toolbox of every event programmer. AnyEvent::AIO transparently fuses
1134L<IO::AIO> and AnyEvent together, giving AnyEvent access to event-based
1135file I/O, and much more.
1091 1136
1092=item L<AnyEvent::HTTPD> 1137=item L<AnyEvent::HTTPD>
1093 1138
1094Provides a simple web application server framework. 1139A simple embedded webserver.
1095 1140
1096=item L<AnyEvent::FastPing> 1141=item L<AnyEvent::FastPing>
1097 1142
1098The fastest ping in the west. 1143The fastest ping in the west.
1099
1100=item L<AnyEvent::DBI>
1101
1102Executes L<DBI> requests asynchronously in a proxy process.
1103
1104=item L<AnyEvent::AIO>
1105
1106Truly asynchronous I/O, should be in the toolbox of every event
1107programmer. AnyEvent::AIO transparently fuses L<IO::AIO> and AnyEvent
1108together.
1109
1110=item L<AnyEvent::BDB>
1111
1112Truly asynchronous Berkeley DB access. AnyEvent::BDB transparently fuses
1113L<BDB> and AnyEvent together.
1114
1115=item L<AnyEvent::GPSD>
1116
1117A non-blocking interface to gpsd, a daemon delivering GPS information.
1118
1119=item L<AnyEvent::IRC>
1120
1121AnyEvent based IRC client module family (replacing the older Net::IRC3).
1122
1123=item L<AnyEvent::XMPP>
1124
1125AnyEvent based XMPP (Jabber protocol) module family (replacing the older
1126Net::XMPP2>.
1127
1128=item L<AnyEvent::IGS>
1129
1130A non-blocking interface to the Internet Go Server protocol (used by
1131L<App::IGS>).
1132
1133=item L<Net::FCP>
1134
1135AnyEvent-based implementation of the Freenet Client Protocol, birthplace
1136of AnyEvent.
1137
1138=item L<Event::ExecFlow>
1139
1140High level API for event-based execution flow control.
1141 1144
1142=item L<Coro> 1145=item L<Coro>
1143 1146
1144Has special support for AnyEvent via L<Coro::AnyEvent>. 1147Has special support for AnyEvent via L<Coro::AnyEvent>.
1145 1148
1149 1152
1150package AnyEvent; 1153package AnyEvent;
1151 1154
1152# basically a tuned-down version of common::sense 1155# basically a tuned-down version of common::sense
1153sub common_sense { 1156sub common_sense {
1154 # from common:.sense 1.0 1157 # from common:.sense 3.4
1155 ${^WARNING_BITS} = "\xfc\x3f\x33\x00\x0f\xf3\xcf\xc0\xf3\xfc\x33\x00"; 1158 ${^WARNING_BITS} ^= ${^WARNING_BITS} ^ "\x3c\x3f\x33\x00\x0f\xf0\x0f\xc0\xf0\xfc\x33\x00";
1156 # use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl) 1159 # use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl)
1157 $^H |= 0x00000600; 1160 $^H |= 0x00000600;
1158} 1161}
1159 1162
1160BEGIN { AnyEvent::common_sense } 1163BEGIN { AnyEvent::common_sense }
1161 1164
1162use Carp (); 1165use Carp ();
1163 1166
1164our $VERSION = '5.26'; 1167our $VERSION = '5.34';
1165our $MODEL; 1168our $MODEL;
1166 1169
1167our $AUTOLOAD; 1170our $AUTOLOAD;
1168our @ISA; 1171our @ISA;
1169 1172
1194 $ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6"; 1197 $ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6";
1195} 1198}
1196 1199
1197my @models = ( 1200my @models = (
1198 [EV:: => AnyEvent::Impl::EV:: , 1], 1201 [EV:: => AnyEvent::Impl::EV:: , 1],
1199 [AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl:: , 1], 1202 [AnyEvent::Loop:: => AnyEvent::Impl::Perl:: , 1],
1200 # everything below here will not (normally) be autoprobed 1203 # everything below here will not (normally) be autoprobed
1201 # as the pureperl backend should work everywhere 1204 # as the pure perl backend should work everywhere
1202 # and is usually faster 1205 # and is usually faster
1203 [Event:: => AnyEvent::Impl::Event::, 1], 1206 [Event:: => AnyEvent::Impl::Event::, 1],
1204 [Glib:: => AnyEvent::Impl::Glib:: , 1], # becomes extremely slow with many watchers 1207 [Glib:: => AnyEvent::Impl::Glib:: , 1], # becomes extremely slow with many watchers
1205 [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy 1208 [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
1206 [Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package 1209 [Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package
1207 [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles 1210 [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
1208 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program 1211 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program
1209 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza 1212 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
1210 [Wx:: => AnyEvent::Impl::POE::], 1213 [Wx:: => AnyEvent::Impl::POE::],
1211 [Prima:: => AnyEvent::Impl::POE::], 1214 [Prima:: => AnyEvent::Impl::POE::],
1212 # IO::Async is just too broken - we would need workarounds for its
1213 # byzantine signal and broken child handling, among others.
1214 # IO::Async is rather hard to detect, as it doesn't have any
1215 # obvious default class.
1216 [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program
1217 [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program 1215 [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::],
1218 [IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program 1216 [Cocoa::EventLoop:: => AnyEvent::Impl::Cocoa::],
1219 [AnyEvent::Impl::IOAsync:: => AnyEvent::Impl::IOAsync::], # requires special main program 1217 [FLTK:: => AnyEvent::Impl::FLTK::],
1220); 1218);
1221 1219
1222our %method = map +($_ => 1), 1220our %method = map +($_ => 1),
1223 qw(io timer time now now_update signal child idle condvar one_event DESTROY); 1221 qw(io timer time now now_update signal child idle condvar DESTROY);
1224 1222
1225our @post_detect; 1223our @post_detect;
1226 1224
1227sub post_detect(&) { 1225sub post_detect(&) {
1228 my ($cb) = @_; 1226 my ($cb) = @_;
1283 last; 1281 last;
1284 } 1282 }
1285 } 1283 }
1286 1284
1287 $MODEL 1285 $MODEL
1288 or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.\n"; 1286 or die "AnyEvent: backend autodetection failed - did you properly install AnyEvent?\n";
1289 } 1287 }
1290 } 1288 }
1291 1289
1292 @models = (); # free probe data 1290 @models = (); # free probe data
1293 1291
1294 push @{"$MODEL\::ISA"}, "AnyEvent::Base"; 1292 push @{"$MODEL\::ISA"}, "AnyEvent::Base";
1295 unshift @ISA, $MODEL; 1293 unshift @ISA, $MODEL;
1296 1294
1297 # now nuke some methods that are overriden by the backend. 1295 # now nuke some methods that are overridden by the backend.
1298 # SUPER is not allowed. 1296 # SUPER is not allowed.
1299 for (qw(time signal child idle)) { 1297 for (qw(time signal child idle)) {
1300 undef &{"AnyEvent::Base::$_"} 1298 undef &{"AnyEvent::Base::$_"}
1301 if defined &{"$MODEL\::$_"}; 1299 if defined &{"$MODEL\::$_"};
1302 } 1300 }
1303 1301
1304 require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT}; 1302 if ($ENV{PERL_ANYEVENT_STRICT}) {
1303 eval { require AnyEvent::Strict };
1304 warn "AnyEvent: cannot load AnyEvent::Strict: $@"
1305 if $@ && $VERBOSE;
1306 }
1305 1307
1306 (shift @post_detect)->() while @post_detect; 1308 (shift @post_detect)->() while @post_detect;
1307 1309
1308 *post_detect = sub(&) { 1310 *post_detect = sub(&) {
1309 shift->(); 1311 shift->();
1421 1423
1422*now = \&time; 1424*now = \&time;
1423 1425
1424sub now_update { } 1426sub now_update { }
1425 1427
1428sub _poll {
1429 Carp::croak "$AnyEvent::MODEL does not support blocking waits. Caught";
1430}
1431
1426# default implementation for ->condvar 1432# default implementation for ->condvar
1433# in fact,t he default should not be overwritten
1427 1434
1428sub condvar { 1435sub condvar {
1429 eval q{ # poor man's autoloading {} 1436 eval q{ # poor man's autoloading {}
1430 *condvar = sub { 1437 *condvar = sub {
1431 bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar" 1438 bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"
1616# default implementation for ->child 1623# default implementation for ->child
1617 1624
1618our %PID_CB; 1625our %PID_CB;
1619our $CHLD_W; 1626our $CHLD_W;
1620our $CHLD_DELAY_W; 1627our $CHLD_DELAY_W;
1621our $WNOHANG;
1622 1628
1623# used by many Impl's 1629# used by many Impl's
1624sub _emit_childstatus($$) { 1630sub _emit_childstatus($$) {
1625 my (undef, $rpid, $rstatus) = @_; 1631 my (undef, $rpid, $rstatus) = @_;
1626 1632
1633 eval q{ # poor man's autoloading {} 1639 eval q{ # poor man's autoloading {}
1634 *_sigchld = sub { 1640 *_sigchld = sub {
1635 my $pid; 1641 my $pid;
1636 1642
1637 AnyEvent->_emit_childstatus ($pid, $?) 1643 AnyEvent->_emit_childstatus ($pid, $?)
1638 while ($pid = waitpid -1, $WNOHANG) > 0; 1644 while ($pid = waitpid -1, WNOHANG) > 0;
1639 }; 1645 };
1640 1646
1641 *child = sub { 1647 *child = sub {
1642 my (undef, %arg) = @_; 1648 my (undef, %arg) = @_;
1643 1649
1644 defined (my $pid = $arg{pid} + 0) 1650 my $pid = $arg{pid};
1645 or Carp::croak "required option 'pid' is missing"; 1651 my $cb = $arg{cb};
1646 1652
1647 $PID_CB{$pid}{$arg{cb}} = $arg{cb}; 1653 $PID_CB{$pid}{$cb+0} = $cb;
1648
1649 # WNOHANG is almost cetrainly 1 everywhere
1650 $WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/
1651 ? 1
1652 : eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1;
1653 1654
1654 unless ($CHLD_W) { 1655 unless ($CHLD_W) {
1655 $CHLD_W = AE::signal CHLD => \&_sigchld; 1656 $CHLD_W = AE::signal CHLD => \&_sigchld;
1656 # child could be a zombie already, so make at least one round 1657 # child could be a zombie already, so make at least one round
1657 &_sigchld; 1658 &_sigchld;
1658 } 1659 }
1659 1660
1660 bless [$pid, $arg{cb}], "AnyEvent::Base::child" 1661 bless [$pid, $cb+0], "AnyEvent::Base::child"
1661 }; 1662 };
1662 1663
1663 *AnyEvent::Base::child::DESTROY = sub { 1664 *AnyEvent::Base::child::DESTROY = sub {
1664 my ($pid, $cb) = @{$_[0]}; 1665 my ($pid, $icb) = @{$_[0]};
1665 1666
1666 delete $PID_CB{$pid}{$cb}; 1667 delete $PID_CB{$pid}{$icb};
1667 delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} }; 1668 delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };
1668 1669
1669 undef $CHLD_W unless keys %PID_CB; 1670 undef $CHLD_W unless keys %PID_CB;
1670 }; 1671 };
1671 }; 1672 };
1719 1720
1720package AnyEvent::CondVar; 1721package AnyEvent::CondVar;
1721 1722
1722our @ISA = AnyEvent::CondVar::Base::; 1723our @ISA = AnyEvent::CondVar::Base::;
1723 1724
1725# only to be used for subclassing
1726sub new {
1727 my $class = shift;
1728 bless AnyEvent->condvar (@_), $class
1729}
1730
1724package AnyEvent::CondVar::Base; 1731package AnyEvent::CondVar::Base;
1725 1732
1726#use overload 1733#use overload
1727# '&{}' => sub { my $self = shift; sub { $self->send (@_) } }, 1734# '&{}' => sub { my $self = shift; sub { $self->send (@_) } },
1728# fallback => 1; 1735# fallback => 1;
1737 1744
1738sub _send { 1745sub _send {
1739 # nop 1746 # nop
1740} 1747}
1741 1748
1749sub _wait {
1750 AnyEvent->_poll until $_[0]{_ae_sent};
1751}
1752
1742sub send { 1753sub send {
1743 my $cv = shift; 1754 my $cv = shift;
1744 $cv->{_ae_sent} = [@_]; 1755 $cv->{_ae_sent} = [@_];
1745 (delete $cv->{_ae_cb})->($cv) if $cv->{_ae_cb}; 1756 (delete $cv->{_ae_cb})->($cv) if $cv->{_ae_cb};
1746 $cv->_send; 1757 $cv->_send;
1753 1764
1754sub ready { 1765sub ready {
1755 $_[0]{_ae_sent} 1766 $_[0]{_ae_sent}
1756} 1767}
1757 1768
1758sub _wait {
1759 $WAITING
1760 and !$_[0]{_ae_sent}
1761 and Carp::croak "AnyEvent::CondVar: recursive blocking wait detected";
1762
1763 local $WAITING = 1;
1764 AnyEvent->one_event while !$_[0]{_ae_sent};
1765}
1766
1767sub recv { 1769sub recv {
1770 unless ($_[0]{_ae_sent}) {
1771 $WAITING
1772 and Carp::croak "AnyEvent::CondVar: recursive blocking wait attempted";
1773
1774 local $WAITING = 1;
1768 $_[0]->_wait; 1775 $_[0]->_wait;
1776 }
1769 1777
1770 Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak}; 1778 $_[0]{_ae_croak}
1771 wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0] 1779 and Carp::croak $_[0]{_ae_croak};
1780
1781 wantarray
1782 ? @{ $_[0]{_ae_sent} }
1783 : $_[0]{_ae_sent}[0]
1772} 1784}
1773 1785
1774sub cb { 1786sub cb {
1775 my $cv = shift; 1787 my $cv = shift;
1776 1788
1792 &{ $_[0]{_ae_end_cb} || sub { $_[0]->send } }; 1804 &{ $_[0]{_ae_end_cb} || sub { $_[0]->send } };
1793} 1805}
1794 1806
1795# undocumented/compatibility with pre-3.4 1807# undocumented/compatibility with pre-3.4
1796*broadcast = \&send; 1808*broadcast = \&send;
1797*wait = \&_wait; 1809*wait = \&recv;
1798 1810
1799=head1 ERROR AND EXCEPTION HANDLING 1811=head1 ERROR AND EXCEPTION HANDLING
1800 1812
1801In general, AnyEvent does not do any error handling - it relies on the 1813In general, AnyEvent does not do any error handling - it relies on the
1802caller to do that if required. The L<AnyEvent::Strict> module (see also 1814caller to do that if required. The L<AnyEvent::Strict> module (see also
1849check the arguments passed to most method calls. If it finds any problems, 1861check the arguments passed to most method calls. If it finds any problems,
1850it will croak. 1862it will croak.
1851 1863
1852In other words, enables "strict" mode. 1864In other words, enables "strict" mode.
1853 1865
1854Unlike C<use strict> (or it's modern cousin, C<< use L<common::sense> 1866Unlike C<use strict> (or its modern cousin, C<< use L<common::sense>
1855>>, it is definitely recommended to keep it off in production. Keeping 1867>>, it is definitely recommended to keep it off in production. Keeping
1856C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs 1868C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs
1857can be very useful, however. 1869can be very useful, however.
1858 1870
1859=item C<PERL_ANYEVENT_MODEL> 1871=item C<PERL_ANYEVENT_MODEL>
1865used as event model. If it fails to load AnyEvent will proceed with 1877used as event model. If it fails to load AnyEvent will proceed with
1866auto detection and -probing. 1878auto detection and -probing.
1867 1879
1868This functionality might change in future versions. 1880This functionality might change in future versions.
1869 1881
1870For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you 1882For example, to force the pure perl model (L<AnyEvent::Loop::Perl>) you
1871could start your program like this: 1883could start your program like this:
1872 1884
1873 PERL_ANYEVENT_MODEL=Perl perl ... 1885 PERL_ANYEVENT_MODEL=Perl perl ...
1874 1886
1875=item C<PERL_ANYEVENT_PROTOCOLS> 1887=item C<PERL_ANYEVENT_PROTOCOLS>
2505 unless defined $SIG{PIPE}; 2517 unless defined $SIG{PIPE};
2506 2518
2507=head1 RECOMMENDED/OPTIONAL MODULES 2519=head1 RECOMMENDED/OPTIONAL MODULES
2508 2520
2509One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and 2521One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and
2510it's built-in modules) are required to use it. 2522its built-in modules) are required to use it.
2511 2523
2512That does not mean that AnyEvent won't take advantage of some additional 2524That does not mean that AnyEvent won't take advantage of some additional
2513modules if they are installed. 2525modules if they are installed.
2514 2526
2515This section explains which additional modules will be used, and how they 2527This section explains which additional modules will be used, and how they
2573the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL. 2585the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL.
2574 2586
2575=item L<Time::HiRes> 2587=item L<Time::HiRes>
2576 2588
2577This module is part of perl since release 5.008. It will be used when the 2589This module is part of perl since release 5.008. It will be used when the
2578chosen event library does not come with a timing source on it's own. The 2590chosen event library does not come with a timing source of its own. The
2579pure-perl event loop (L<AnyEvent::Impl::Perl>) will additionally use it to 2591pure-perl event loop (L<AnyEvent::Loop>) will additionally load it to
2580try to use a monotonic clock for timing stability. 2592try to use a monotonic clock for timing stability.
2581 2593
2582=back 2594=back
2583 2595
2584 2596
2646pronounced). 2658pronounced).
2647 2659
2648 2660
2649=head1 SEE ALSO 2661=head1 SEE ALSO
2650 2662
2663Tutorial/Introduction: L<AnyEvent::Intro>.
2664
2665FAQ: L<AnyEvent::FAQ>.
2666
2651Utility functions: L<AnyEvent::Util>. 2667Utility functions: L<AnyEvent::Util>.
2652 2668
2653Event modules: L<EV>, L<EV::Glib>, L<Glib::EV>, L<Event>, L<Glib::Event>, 2669Event modules: L<AnyEvent::Loop>, L<EV>, L<EV::Glib>, L<Glib::EV>,
2654L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. 2670L<Event>, L<Glib::Event>, L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.
2655 2671
2656Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>, 2672Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,
2657L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>, 2673L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,
2658L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>, 2674L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,
2659L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>. 2675L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>.
2661Non-blocking file handles, sockets, TCP clients and 2677Non-blocking file handles, sockets, TCP clients and
2662servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>. 2678servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.
2663 2679
2664Asynchronous DNS: L<AnyEvent::DNS>. 2680Asynchronous DNS: L<AnyEvent::DNS>.
2665 2681
2666Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, 2682Thread support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>.
2667L<Coro::Event>,
2668 2683
2669Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::XMPP>, 2684Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::IRC>,
2670L<AnyEvent::HTTP>. 2685L<AnyEvent::HTTP>.
2671 2686
2672 2687
2673=head1 AUTHOR 2688=head1 AUTHOR
2674 2689

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