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Revision 1.306 by root, Tue Dec 15 05:49:13 2009 UTC vs.
Revision 1.347 by root, Sun Jan 23 11:15:09 2011 UTC

7 7
8=head1 SYNOPSIS 8=head1 SYNOPSIS
9 9
10 use AnyEvent; 10 use AnyEvent;
11 11
12 # if you prefer function calls, look at the AE manpage for
13 # an alternative API.
14
12 # file descriptor readable 15 # file handle or descriptor readable
13 my $w = AnyEvent->io (fh => $fh, poll => "r", cb => sub { ... }); 16 my $w = AnyEvent->io (fh => $fh, poll => "r", cb => sub { ... });
14 17
15 # one-shot or repeating timers 18 # one-shot or repeating timers
16 my $w = AnyEvent->timer (after => $seconds, cb => sub { ... }); 19 my $w = AnyEvent->timer (after => $seconds, cb => sub { ... });
17 my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ... 20 my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ...);
18 21
19 print AnyEvent->now; # prints current event loop time 22 print AnyEvent->now; # prints current event loop time
20 print AnyEvent->time; # think Time::HiRes::time or simply CORE::time. 23 print AnyEvent->time; # think Time::HiRes::time or simply CORE::time.
21 24
22 # POSIX signal 25 # POSIX signal
43in a tutorial or some gentle introduction, have a look at the 46in a tutorial or some gentle introduction, have a look at the
44L<AnyEvent::Intro> manpage. 47L<AnyEvent::Intro> manpage.
45 48
46=head1 SUPPORT 49=head1 SUPPORT
47 50
51An FAQ document is available as L<AnyEvent::FAQ>.
52
48There is a mailinglist for discussing all things AnyEvent, and an IRC 53There also is a mailinglist for discussing all things AnyEvent, and an IRC
49channel, too. 54channel, too.
50 55
51See the AnyEvent project page at the B<Schmorpforge Ta-Sa Software 56See the AnyEvent project page at the B<Schmorpforge Ta-Sa Software
52Repository>, at L<http://anyevent.schmorp.de>, for more info. 57Repository>, at L<http://anyevent.schmorp.de>, for more info.
53 58
73module 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
74model you use. 79model you use.
75 80
76For 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
77actually 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
78like 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
79cannot use anything else, as they are simply incompatible to everything 84cannot use anything else, as they are simply incompatible to everything
80that 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
81module 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.
82 87
83AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works 88AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works
84fine. 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
85with 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
86your 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
87too. But if your module uses AnyEvent, it works transparently with all 92your module uses AnyEvent, it works transparently with all event models it
88event 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
89use 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,
90to AnyEvent, too, so it is future-proof). 95so it is future-proof).
91 96
92In 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
93model>, 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
94modules, 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
95follow. 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
96offering 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
97technically possible. 102technically possible.
98 103
99Of course, AnyEvent comes with a big (and fully optional!) toolbox 104Of course, AnyEvent comes with a big (and fully optional!) toolbox
100of useful functionality, such as an asynchronous DNS resolver, 100% 105of useful functionality, such as an asynchronous DNS resolver, 100%
106useful) 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
107model, you should I<not> use this module. 112model, you should I<not> use this module.
108 113
109=head1 DESCRIPTION 114=head1 DESCRIPTION
110 115
111L<AnyEvent> provides an identical interface to multiple event loops. This 116L<AnyEvent> provides a uniform interface to various event loops. This
112allows module authors to utilise an event loop without forcing module 117allows module authors to use event loop functionality without forcing
113users 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
114peacefully at any one time). 119than one event loop cannot coexist peacefully).
115 120
116The 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>
117module. 122module.
118 123
119During the first call of any watcher-creation method, the module tries 124During the first call of any watcher-creation method, the module tries
120to 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
121following modules is already loaded: L<EV>, 126following modules is already loaded: L<EV>, L<AnyEvent::Impl::Perl>,
122L<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
123L<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
124to 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
125adaptor should always succeed) in the order given. The first one that can 130available, the pure-perl L<AnyEvent::Impl::Perl> should always work, so
126be successfully loaded will be used. If, after this, still none could be 131the other two are not normally tried.
127found, AnyEvent will fall back to a pure-perl event loop, which is not
128very efficient, but should work everywhere.
129 132
130Because AnyEvent first checks for modules that are already loaded, loading 133Because AnyEvent first checks for modules that are already loaded, loading
131an event model explicitly before first using AnyEvent will likely make 134an event model explicitly before first using AnyEvent will likely make
132that model the default. For example: 135that model the default. For example:
133 136
135 use AnyEvent; 138 use AnyEvent;
136 139
137 # .. AnyEvent will likely default to Tk 140 # .. AnyEvent will likely default to Tk
138 141
139The 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
140starts 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,
141use AnyEvent so their modules work together with others seamlessly... 144as very few modules hardcode event loops without announcing this very
145loudly.
142 146
143The pure-perl implementation of AnyEvent is called 147The pure-perl implementation of AnyEvent is called
144C<AnyEvent::Impl::Perl>. Like other event modules you can load it 148C<AnyEvent::Impl::Perl>. Like other event modules you can load it
145explicitly and enjoy the high availability of that event loop :) 149explicitly and enjoy the high availability of that event loop :)
146 150
155callback when the event occurs (of course, only when the event model 159callback when the event occurs (of course, only when the event model
156is in control). 160is in control).
157 161
158Note that B<callbacks must not permanently change global variables> 162Note that B<callbacks must not permanently change global variables>
159potentially 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<<
160callbacks must not C<die> >>. The former is good programming practise in 164callbacks must not C<die> >>. The former is good programming practice in
161Perl and the latter stems from the fact that exception handling differs 165Perl and the latter stems from the fact that exception handling differs
162widely between event loops. 166widely between event loops.
163 167
164To 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
165variable 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
166to it). 170to it).
167 171
168All 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.
169 173
170Many watchers either are used with "recursion" (repeating timers for 174Many watchers either are used with "recursion" (repeating timers for
171example), or need to refer to their watcher object in other ways. 175example), or need to refer to their watcher object in other ways.
172 176
173An any way to achieve that is this pattern: 177One way to achieve that is this pattern:
174 178
175 my $w; $w = AnyEvent->type (arg => value ..., cb => sub { 179 my $w; $w = AnyEvent->type (arg => value ..., cb => sub {
176 # you can use $w here, for example to undef it 180 # you can use $w here, for example to undef it
177 undef $w; 181 undef $w;
178 }); 182 });
210 214
211The 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.
212You 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
213underlying file descriptor. 217underlying file descriptor.
214 218
215Some event loops issue spurious readyness notifications, so you should 219Some event loops issue spurious readiness notifications, so you should
216always use non-blocking calls when reading/writing from/to your file 220always use non-blocking calls when reading/writing from/to your file
217handles. 221handles.
218 222
219Example: 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
220watcher. 224watcher.
244 248
245Although the callback might get passed parameters, their value and 249Although the callback might get passed parameters, their value and
246presence is undefined and you cannot rely on them. Portable AnyEvent 250presence is undefined and you cannot rely on them. Portable AnyEvent
247callbacks cannot use arguments passed to time watcher callbacks. 251callbacks cannot use arguments passed to time watcher callbacks.
248 252
249The callback will normally be invoked once only. If you specify another 253The callback will normally be invoked only once. If you specify another
250parameter, C<interval>, as a strictly positive number (> 0), then the 254parameter, C<interval>, as a strictly positive number (> 0), then the
251callback will be invoked regularly at that interval (in fractional 255callback will be invoked regularly at that interval (in fractional
252seconds) after the first invocation. If C<interval> is specified with a 256seconds) after the first invocation. If C<interval> is specified with a
253false value, then it is treated as if it were missing. 257false value, then it is treated as if it were not specified at all.
254 258
255The callback will be rescheduled before invoking the callback, but no 259The callback will be rescheduled before invoking the callback, but no
256attempt 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
257only approximate. 261only approximate.
258 262
259Example: fire an event after 7.7 seconds. 263Example: fire an event after 7.7 seconds.
260 264
261 my $w = AnyEvent->timer (after => 7.7, cb => sub { 265 my $w = AnyEvent->timer (after => 7.7, cb => sub {
279 283
280While 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
281use absolute time internally. This makes a difference when your clock 285use absolute time internally. This makes a difference when your clock
282"jumps", for example, when ntp decides to set your clock backwards from 286"jumps", for example, when ntp decides to set your clock backwards from
283the 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
284fire "after" a second might actually take six years to finally fire. 288fire "after a second" might actually take six years to finally fire.
285 289
286AnyEvent cannot compensate for this. The only event loop that is conscious 290AnyEvent cannot compensate for this. The only event loop that is conscious
287about 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
288on true relative time) and absolute (ev_periodic, based on wallclock time) 292on true relative time) and absolute (ev_periodic, based on wallclock time)
289timers. 293timers.
290 294
291AnyEvent always prefers relative timers, if available, matching the 295AnyEvent always prefers relative timers, if available, matching the
292AnyEvent API. 296AnyEvent API.
314I<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
315function to call when you want to know the current time.> 319function to call when you want to know the current time.>
316 320
317This function is also often faster then C<< AnyEvent->time >>, and 321This function is also often faster then C<< AnyEvent->time >>, and
318thus the preferred method if you want some timestamp (for example, 322thus the preferred method if you want some timestamp (for example,
319L<AnyEvent::Handle> uses this to update it's activity timeouts). 323L<AnyEvent::Handle> uses this to update its activity timeouts).
320 324
321The 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
322with your timing, you can skip it without bad conscience. 326with your timing; you can skip it without a bad conscience.
323 327
324For 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>
325and L<EV> and the following set-up: 329and L<EV> and the following set-up:
326 330
327The 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
328time=500 (assume no other callbacks delay processing). In your callback, 332time=500 (assume no other callbacks delay processing). In your callback,
329you 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
330second) 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
331after three seconds. 335after three seconds.
332 336
425=head3 Signal Races, Delays and Workarounds 429=head3 Signal Races, Delays and Workarounds
426 430
427Many 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
428callbacks 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
429do race-free signal handling in perl, requiring C libraries for 433do race-free signal handling in perl, requiring C libraries for
430this. 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,
431signals 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
432specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This 436specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This
433variable can be changed only before the first signal watcher is created, 437variable can be changed only before the first signal watcher is created,
434and should be left alone otherwise. This variable determines how often 438and should be left alone otherwise. This variable determines how often
435AnyEvent 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
437saving. 441saving.
438 442
439All these problems can be avoided by installing the optional 443All these problems can be avoided by installing the optional
440L<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
441work 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>
442(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
443one-second latency). For those, you just have to suffer the delays. 447one-second latency). For those, you just have to suffer the delays.
444 448
445=head2 CHILD PROCESS WATCHERS 449=head2 CHILD PROCESS WATCHERS
446 450
447 $w = AnyEvent->child (pid => <process id>, cb => <callback>); 451 $w = AnyEvent->child (pid => <process id>, cb => <callback>);
448 452
449You 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.
450 454
451The 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,
452using 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
453croak). The watcher will be triggered only when the child process has 457croak). The watcher will be triggered only when the child process has
454finished and an exit status is available, not on any trace events 458finished and an exit status is available, not on any trace events
455(stopped/continued). 459(stopped/continued).
456 460
503 507
504=head2 IDLE WATCHERS 508=head2 IDLE WATCHERS
505 509
506 $w = AnyEvent->idle (cb => <callback>); 510 $w = AnyEvent->idle (cb => <callback>);
507 511
508Sometimes there is a need to do something, but it is not so important 512This will repeatedly invoke the callback after the process becomes idle,
509to do it instantly, but only when there is nothing better to do. This 513until either the watcher is destroyed or new events have been detected.
510"nothing better to do" is usually defined to be "no other events need
511attention by the event loop".
512 514
513Idle watchers ideally get invoked when the event loop has nothing 515Idle watchers are useful when there is a need to do something, but it
514better to do, just before it would block the process to wait for new 516is not so important (or wise) to do it instantly. The callback will be
515events. Instead of blocking, the idle watcher is invoked. 517invoked only when there is "nothing better to do", which is usually
518defined as "all outstanding events have been handled and no new events
519have been detected". That means that idle watchers ideally get invoked
520when the event loop has just polled for new events but none have been
521detected. Instead of blocking to wait for more events, the idle watchers
522will be invoked.
516 523
517Most event loops unfortunately do not really support idle watchers (only 524Unfortunately, most event loops do not really support idle watchers (only
518EV, Event and Glib do it in a usable fashion) - for the rest, AnyEvent 525EV, Event and Glib do it in a usable fashion) - for the rest, AnyEvent
519will simply call the callback "from time to time". 526will simply call the callback "from time to time".
520 527
521Example: read lines from STDIN, but only process them when the 528Example: read lines from STDIN, but only process them when the
522program is otherwise idle: 529program is otherwise idle:
550will actively watch for new events and call your callbacks. 557will actively watch for new events and call your callbacks.
551 558
552AnyEvent is slightly different: it expects somebody else to run the event 559AnyEvent is slightly different: it expects somebody else to run the event
553loop 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).
554 561
555The instrument to do that is called a "condition variable", so called 562The tool to do that is called a "condition variable", so called because
556because they represent a condition that must become true. 563they represent a condition that must become true.
557 564
558Now 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.
559 566
560Condition variables can be created by calling the C<< AnyEvent->condvar 567Condition variables can be created by calling the C<< AnyEvent->condvar
561>> method, usually without arguments. The only argument pair allowed is 568>> method, usually without arguments. The only argument pair allowed is
566After creation, the condition variable is "false" until it becomes "true" 573After creation, the condition variable is "false" until it becomes "true"
567by 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
568were 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<<
569->send >> method). 576->send >> method).
570 577
571Condition variables are similar to callbacks, except that you can 578Since condition variables are the most complex part of the AnyEvent API, here are
572optionally 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:
573in time where multiple outstanding events have been processed. And yet 580
574another way to call them is transactions - each condition variable can be 581=over 4
575used to represent a transaction, which finishes at some point and delivers 582
576a 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
577compute/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
578 601
579Condition variables are very useful to signal that something has finished, 602Condition variables are very useful to signal that something has finished,
580for example, if you write a module that does asynchronous http requests, 603for example, if you write a module that does asynchronous http requests,
581then a condition variable would be the ideal candidate to signal the 604then a condition variable would be the ideal candidate to signal the
582availability of results. The user can either act when the callback is 605availability of results. The user can either act when the callback is
595 618
596Condition variables are represented by hash refs in perl, and the keys 619Condition variables are represented by hash refs in perl, and the keys
597used 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
598easy (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
599AnyEvent). To subclass, use C<AnyEvent::CondVar> as base class and call 622AnyEvent). To subclass, use C<AnyEvent::CondVar> as base class and call
600it's C<new> method in your own C<new> method. 623its C<new> method in your own C<new> method.
601 624
602There are two "sides" to a condition variable - the "producer side" which 625There are two "sides" to a condition variable - the "producer side" which
603eventually calls C<< -> send >>, and the "consumer side", which waits 626eventually calls C<< -> send >>, and the "consumer side", which waits
604for the send to occur. 627for the send to occur.
605 628
606Example: wait for a timer. 629Example: wait for a timer.
607 630
608 # wait till the result is ready 631 # condition: "wait till the timer is fired"
609 my $result_ready = AnyEvent->condvar; 632 my $timer_fired = AnyEvent->condvar;
610 633
611 # do something such as adding a timer 634 # create the timer - we could wait for, say
612 # or socket watcher the calls $result_ready->send 635 # a handle becomign ready, or even an
613 # when the "result" is ready. 636 # AnyEvent::HTTP request to finish, but
614 # in this case, we simply use a timer: 637 # in this case, we simply use a timer:
615 my $w = AnyEvent->timer ( 638 my $w = AnyEvent->timer (
616 after => 1, 639 after => 1,
617 cb => sub { $result_ready->send }, 640 cb => sub { $timer_fired->send },
618 ); 641 );
619 642
620 # this "blocks" (while handling events) till the callback 643 # this "blocks" (while handling events) till the callback
621 # calls ->send 644 # calls ->send
622 $result_ready->recv; 645 $timer_fired->recv;
623 646
624Example: wait for a timer, but take advantage of the fact that condition 647Example: wait for a timer, but take advantage of the fact that condition
625variables are also callable directly. 648variables are also callable directly.
626 649
627 my $done = AnyEvent->condvar; 650 my $done = AnyEvent->condvar;
670they 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
671C<send>. 694C<send>.
672 695
673=item $cv->croak ($error) 696=item $cv->croak ($error)
674 697
675Similar to send, but causes all call's to C<< ->recv >> to invoke 698Similar to send, but causes all calls to C<< ->recv >> to invoke
676C<Carp::croak> with the given error message/object/scalar. 699C<Carp::croak> with the given error message/object/scalar.
677 700
678This can be used to signal any errors to the condition variable 701This can be used to signal any errors to the condition variable
679user/consumer. Doing it this way instead of calling C<croak> directly 702user/consumer. Doing it this way instead of calling C<croak> directly
680delays the error detetcion, but has the overwhelmign advantage that it 703delays the error detection, but has the overwhelming advantage that it
681diagnoses 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
682deep in some event clalback without connection to the actual code causing 705deep in some event callback with no connection to the actual code causing
683the problem. 706the problem.
684 707
685=item $cv->begin ([group callback]) 708=item $cv->begin ([group callback])
686 709
687=item $cv->end 710=item $cv->end
725one 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
726sending. 749sending.
727 750
728The ping example mentioned above is slightly more complicated, as the 751The ping example mentioned above is slightly more complicated, as the
729there 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
730begung can potentially be zero: 753begun can potentially be zero:
731 754
732 my $cv = AnyEvent->condvar; 755 my $cv = AnyEvent->condvar;
733 756
734 my %result; 757 my %result;
735 $cv->begin (sub { shift->send (\%result) }); 758 $cv->begin (sub { shift->send (\%result) });
756to 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
757C<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
758doesn't execute once). 781doesn't execute once).
759 782
760This is the general pattern when you "fan out" into multiple (but 783This is the general pattern when you "fan out" into multiple (but
761potentially 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
762the 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
763subrequest you start, call C<begin> and for each subrequest you finish, 786subrequest you start, call C<begin> and for each subrequest you finish,
764call C<end>. 787call C<end>.
765 788
766=back 789=back
773=over 4 796=over 4
774 797
775=item $cv->recv 798=item $cv->recv
776 799
777Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak 800Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak
778>> methods have been called on c<$cv>, while servicing other watchers 801>> methods have been called on C<$cv>, while servicing other watchers
779normally. 802normally.
780 803
781You 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
782will return immediately. 805will return immediately.
783 806
800caller 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
801condition variables with some kind of request results and supporting 824condition variables with some kind of request results and supporting
802callbacks so the caller knows that getting the result will not block, 825callbacks so the caller knows that getting the result will not block,
803while still supporting blocking waits if the caller so desires). 826while still supporting blocking waits if the caller so desires).
804 827
805You 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
806only calling C<< ->recv >> from within that callback (or at a later 829only calling C<< ->recv >> from within that callback (or at a later
807time). 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
808waits otherwise. 831waits otherwise.
809 832
810=item $bool = $cv->ready 833=item $bool = $cv->ready
815=item $cb = $cv->cb ($cb->($cv)) 838=item $cb = $cv->cb ($cb->($cv))
816 839
817This is a mutator function that returns the callback set and optionally 840This is a mutator function that returns the callback set and optionally
818replaces it before doing so. 841replaces it before doing so.
819 842
820The callback will be called when the condition becomes (or already was) 843The callback will be called when the condition becomes "true", i.e. when
821"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
822the 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
823inside the callback or at any later time is guaranteed not to block. 847the callback or at any later time is guaranteed not to block.
824 848
825=back 849=back
826 850
827=head1 SUPPORTED EVENT LOOPS/BACKENDS 851=head1 SUPPORTED EVENT LOOPS/BACKENDS
828 852
840 AnyEvent::Impl::EV based on EV (interface to libev, best choice). 864 AnyEvent::Impl::EV based on EV (interface to libev, best choice).
841 AnyEvent::Impl::Perl pure-perl implementation, fast and portable. 865 AnyEvent::Impl::Perl pure-perl implementation, fast and portable.
842 866
843=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.
844 868
845These 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
846is 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
847them. This means that AnyEvent will automatically pick the right backend 871them. This means that AnyEvent will automatically pick the right backend
848when the main program loads an event module before anything starts to 872when the main program loads an event module before anything starts to
849create watchers. Nothing special needs to be done by the main program. 873create watchers. Nothing special needs to be done by the main program.
850 874
852 AnyEvent::Impl::Glib based on Glib, slow but very stable. 876 AnyEvent::Impl::Glib based on Glib, slow but very stable.
853 AnyEvent::Impl::Tk based on Tk, very broken. 877 AnyEvent::Impl::Tk based on Tk, very broken.
854 AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. 878 AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
855 AnyEvent::Impl::POE based on POE, very slow, some limitations. 879 AnyEvent::Impl::POE based on POE, very slow, some limitations.
856 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.
857 883
858=item Backends with special needs. 884=item Backends with special needs.
859 885
860Qt requires the Qt::Application to be instantiated first, but will 886Qt requires the Qt::Application to be instantiated first, but will
861otherwise be picked up automatically. As long as the main program 887otherwise be picked up automatically. As long as the main program
862instantiates the application before any AnyEvent watchers are created, 888instantiates the application before any AnyEvent watchers are created,
863everything should just work. 889everything should just work.
864 890
865 AnyEvent::Impl::Qt based on Qt. 891 AnyEvent::Impl::Qt based on Qt.
866 892
867Support for IO::Async can only be partial, as it is too broken and
868architecturally limited to even support the AnyEvent API. It also
869is the only event loop that needs the loop to be set explicitly, so
870it can only be used by a main program knowing about AnyEvent. See
871L<AnyEvent::Impl::Async> for the gory details.
872
873 AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed.
874
875=item Event loops that are indirectly supported via other backends. 893=item Event loops that are indirectly supported via other backends.
876 894
877Some event loops can be supported via other modules: 895Some event loops can be supported via other modules:
878 896
879There is no direct support for WxWidgets (L<Wx>) or L<Prima>. 897There is no direct support for WxWidgets (L<Wx>) or L<Prima>.
904Contains C<undef> until the first watcher is being created, before the 922Contains C<undef> until the first watcher is being created, before the
905backend has been autodetected. 923backend has been autodetected.
906 924
907Afterwards it contains the event model that is being used, which is the 925Afterwards it contains the event model that is being used, which is the
908name of the Perl class implementing the model. This class is usually one 926name of the Perl class implementing the model. This class is usually one
909of the C<AnyEvent::Impl:xxx> modules, but can be any other class in the 927of the C<AnyEvent::Impl::xxx> modules, but can be any other class in the
910case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it 928case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it
911will be C<urxvt::anyevent>). 929will be C<urxvt::anyevent>).
912 930
913=item AnyEvent::detect 931=item AnyEvent::detect
914 932
915Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model 933Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model
916if necessary. You should only call this function right before you would 934if necessary. You should only call this function right before you would
917have created an AnyEvent watcher anyway, that is, as late as possible at 935have created an AnyEvent watcher anyway, that is, as late as possible at
918runtime, and not e.g. while initialising of your module. 936runtime, and not e.g. during initialisation of your module.
919 937
920If you need to do some initialisation before AnyEvent watchers are 938If you need to do some initialisation before AnyEvent watchers are
921created, use C<post_detect>. 939created, use C<post_detect>.
922 940
923=item $guard = AnyEvent::post_detect { BLOCK } 941=item $guard = AnyEvent::post_detect { BLOCK }
924 942
925Arranges for the code block to be executed as soon as the event model is 943Arranges for the code block to be executed as soon as the event model is
926autodetected (or immediately if this has already happened). 944autodetected (or immediately if that has already happened).
927 945
928The block will be executed I<after> the actual backend has been detected 946The block will be executed I<after> the actual backend has been detected
929(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been 947(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been
930created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do 948created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do
931other initialisations - see the sources of L<AnyEvent::Strict> or 949other initialisations - see the sources of L<AnyEvent::Strict> or
940that automatically removes the callback again when it is destroyed (or 958that automatically removes the callback again when it is destroyed (or
941C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for 959C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for
942a case where this is useful. 960a case where this is useful.
943 961
944Example: Create a watcher for the IO::AIO module and store it in 962Example: Create a watcher for the IO::AIO module and store it in
945C<$WATCHER>. Only do so after the event loop is initialised, though. 963C<$WATCHER>, but do so only do so after the event loop is initialised.
946 964
947 our WATCHER; 965 our WATCHER;
948 966
949 my $guard = AnyEvent::post_detect { 967 my $guard = AnyEvent::post_detect {
950 $WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb); 968 $WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb);
958 $WATCHER ||= $guard; 976 $WATCHER ||= $guard;
959 977
960=item @AnyEvent::post_detect 978=item @AnyEvent::post_detect
961 979
962If there are any code references in this array (you can C<push> to it 980If there are any code references in this array (you can C<push> to it
963before or after loading AnyEvent), then they will called directly after 981before or after loading AnyEvent), then they will be called directly
964the event loop has been chosen. 982after the event loop has been chosen.
965 983
966You should check C<$AnyEvent::MODEL> before adding to this array, though: 984You should check C<$AnyEvent::MODEL> before adding to this array, though:
967if it is defined then the event loop has already been detected, and the 985if it is defined then the event loop has already been detected, and the
968array will be ignored. 986array will be ignored.
969 987
1005because it will stall the whole program, and the whole point of using 1023because it will stall the whole program, and the whole point of using
1006events is to stay interactive. 1024events is to stay interactive.
1007 1025
1008It is fine, however, to call C<< ->recv >> when the user of your module 1026It is fine, however, to call C<< ->recv >> when the user of your module
1009requests it (i.e. if you create a http request object ad have a method 1027requests it (i.e. if you create a http request object ad have a method
1010called C<results> that returns the results, it should call C<< ->recv >> 1028called C<results> that returns the results, it may call C<< ->recv >>
1011freely, as the user of your module knows what she is doing. always). 1029freely, as the user of your module knows what she is doing. Always).
1012 1030
1013=head1 WHAT TO DO IN THE MAIN PROGRAM 1031=head1 WHAT TO DO IN THE MAIN PROGRAM
1014 1032
1015There will always be a single main program - the only place that should 1033There will always be a single main program - the only place that should
1016dictate which event model to use. 1034dictate which event model to use.
1017 1035
1018If it doesn't care, it can just "use AnyEvent" and use it itself, or not 1036If the program is not event-based, it need not do anything special, even
1019do anything special (it does not need to be event-based) and let AnyEvent 1037when it depends on a module that uses an AnyEvent. If the program itself
1020decide which implementation to chose if some module relies on it. 1038uses AnyEvent, but does not care which event loop is used, all it needs
1039to do is C<use AnyEvent>. In either case, AnyEvent will choose the best
1040available loop implementation.
1021 1041
1022If the main program relies on a specific event model - for example, in 1042If the main program relies on a specific event model - for example, in
1023Gtk2 programs you have to rely on the Glib module - you should load the 1043Gtk2 programs you have to rely on the Glib module - you should load the
1024event module before loading AnyEvent or any module that uses it: generally 1044event module before loading AnyEvent or any module that uses it: generally
1025speaking, you should load it as early as possible. The reason is that 1045speaking, you should load it as early as possible. The reason is that
1026modules might create watchers when they are loaded, and AnyEvent will 1046modules might create watchers when they are loaded, and AnyEvent will
1027decide on the event model to use as soon as it creates watchers, and it 1047decide on the event model to use as soon as it creates watchers, and it
1028might chose the wrong one unless you load the correct one yourself. 1048might choose the wrong one unless you load the correct one yourself.
1029 1049
1030You can chose to use a pure-perl implementation by loading the 1050You can chose to use a pure-perl implementation by loading the
1031C<AnyEvent::Impl::Perl> module, which gives you similar behaviour 1051C<AnyEvent::Impl::Perl> module, which gives you similar behaviour
1032everywhere, but letting AnyEvent chose the model is generally better. 1052everywhere, but letting AnyEvent chose the model is generally better.
1033 1053
1051=head1 OTHER MODULES 1071=head1 OTHER MODULES
1052 1072
1053The following is a non-exhaustive list of additional modules that use 1073The following is a non-exhaustive list of additional modules that use
1054AnyEvent as a client and can therefore be mixed easily with other AnyEvent 1074AnyEvent as a client and can therefore be mixed easily with other AnyEvent
1055modules and other event loops in the same program. Some of the modules 1075modules and other event loops in the same program. Some of the modules
1056come with AnyEvent, most are available via CPAN. 1076come as part of AnyEvent, the others are available via CPAN.
1057 1077
1058=over 4 1078=over 4
1059 1079
1060=item L<AnyEvent::Util> 1080=item L<AnyEvent::Util>
1061 1081
1062Contains various utility functions that replace often-used but blocking 1082Contains various utility functions that replace often-used blocking
1063functions such as C<inet_aton> by event-/callback-based versions. 1083functions such as C<inet_aton> with event/callback-based versions.
1064 1084
1065=item L<AnyEvent::Socket> 1085=item L<AnyEvent::Socket>
1066 1086
1067Provides various utility functions for (internet protocol) sockets, 1087Provides various utility functions for (internet protocol) sockets,
1068addresses and name resolution. Also functions to create non-blocking tcp 1088addresses and name resolution. Also functions to create non-blocking tcp
1070 1090
1071=item L<AnyEvent::Handle> 1091=item L<AnyEvent::Handle>
1072 1092
1073Provide read and write buffers, manages watchers for reads and writes, 1093Provide read and write buffers, manages watchers for reads and writes,
1074supports raw and formatted I/O, I/O queued and fully transparent and 1094supports raw and formatted I/O, I/O queued and fully transparent and
1075non-blocking SSL/TLS (via L<AnyEvent::TLS>. 1095non-blocking SSL/TLS (via L<AnyEvent::TLS>).
1076 1096
1077=item L<AnyEvent::DNS> 1097=item L<AnyEvent::DNS>
1078 1098
1079Provides rich asynchronous DNS resolver capabilities. 1099Provides rich asynchronous DNS resolver capabilities.
1080 1100
1101=item L<AnyEvent::HTTP>, L<AnyEvent::IRC>, L<AnyEvent::XMPP>, L<AnyEvent::GPSD>, L<AnyEvent::IGS>, L<AnyEvent::FCP>
1102
1103Implement event-based interfaces to the protocols of the same name (for
1104the curious, IGS is the International Go Server and FCP is the Freenet
1105Client Protocol).
1106
1107=item L<AnyEvent::Handle::UDP>
1108
1109Here be danger!
1110
1111As Pauli would put it, "Not only is it not right, it's not even wrong!" -
1112there are so many things wrong with AnyEvent::Handle::UDP, most notably
1113its use of a stream-based API with a protocol that isn't streamable, that
1114the only way to improve it is to delete it.
1115
1116It features data corruption (but typically only under load) and general
1117confusion. On top, the author is not only clueless about UDP but also
1118fact-resistant - some gems of his understanding: "connect doesn't work
1119with UDP", "UDP packets are not IP packets", "UDP only has datagrams, not
1120packets", "I don't need to implement proper error checking as UDP doesn't
1121support error checking" and so on - he doesn't even understand what's
1122wrong with his module when it is explained to him.
1123
1081=item L<AnyEvent::HTTP> 1124=item L<AnyEvent::DBI>
1082 1125
1083A simple-to-use HTTP library that is capable of making a lot of concurrent 1126Executes L<DBI> requests asynchronously in a proxy process for you,
1084HTTP requests. 1127notifying you in an event-based way when the operation is finished.
1128
1129=item L<AnyEvent::AIO>
1130
1131Truly asynchronous (as opposed to non-blocking) I/O, should be in the
1132toolbox of every event programmer. AnyEvent::AIO transparently fuses
1133L<IO::AIO> and AnyEvent together, giving AnyEvent access to event-based
1134file I/O, and much more.
1085 1135
1086=item L<AnyEvent::HTTPD> 1136=item L<AnyEvent::HTTPD>
1087 1137
1088Provides a simple web application server framework. 1138A simple embedded webserver.
1089 1139
1090=item L<AnyEvent::FastPing> 1140=item L<AnyEvent::FastPing>
1091 1141
1092The fastest ping in the west. 1142The fastest ping in the west.
1093
1094=item L<AnyEvent::DBI>
1095
1096Executes L<DBI> requests asynchronously in a proxy process.
1097
1098=item L<AnyEvent::AIO>
1099
1100Truly asynchronous I/O, should be in the toolbox of every event
1101programmer. AnyEvent::AIO transparently fuses L<IO::AIO> and AnyEvent
1102together.
1103
1104=item L<AnyEvent::BDB>
1105
1106Truly asynchronous Berkeley DB access. AnyEvent::BDB transparently fuses
1107L<BDB> and AnyEvent together.
1108
1109=item L<AnyEvent::GPSD>
1110
1111A non-blocking interface to gpsd, a daemon delivering GPS information.
1112
1113=item L<AnyEvent::IRC>
1114
1115AnyEvent based IRC client module family (replacing the older Net::IRC3).
1116
1117=item L<AnyEvent::XMPP>
1118
1119AnyEvent based XMPP (Jabber protocol) module family (replacing the older
1120Net::XMPP2>.
1121
1122=item L<AnyEvent::IGS>
1123
1124A non-blocking interface to the Internet Go Server protocol (used by
1125L<App::IGS>).
1126
1127=item L<Net::FCP>
1128
1129AnyEvent-based implementation of the Freenet Client Protocol, birthplace
1130of AnyEvent.
1131
1132=item L<Event::ExecFlow>
1133
1134High level API for event-based execution flow control.
1135 1143
1136=item L<Coro> 1144=item L<Coro>
1137 1145
1138Has special support for AnyEvent via L<Coro::AnyEvent>. 1146Has special support for AnyEvent via L<Coro::AnyEvent>.
1139 1147
1143 1151
1144package AnyEvent; 1152package AnyEvent;
1145 1153
1146# basically a tuned-down version of common::sense 1154# basically a tuned-down version of common::sense
1147sub common_sense { 1155sub common_sense {
1148 # from common:.sense 1.0 1156 # from common:.sense 3.4
1149 ${^WARNING_BITS} = "\xfc\x3f\x33\x00\x0f\xf3\xcf\xc0\xf3\xfc\x33\x00"; 1157 ${^WARNING_BITS} ^= ${^WARNING_BITS} ^ "\x3c\x3f\x33\x00\x0f\xf0\x0f\xc0\xf0\xfc\x33\x00";
1150 # use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl) 1158 # use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl)
1151 $^H |= 0x00000600; 1159 $^H |= 0x00000600;
1152} 1160}
1153 1161
1154BEGIN { AnyEvent::common_sense } 1162BEGIN { AnyEvent::common_sense }
1155 1163
1156use Carp (); 1164use Carp ();
1157 1165
1158our $VERSION = '5.22'; 1166our $VERSION = '5.31';
1159our $MODEL; 1167our $MODEL;
1160 1168
1161our $AUTOLOAD; 1169our $AUTOLOAD;
1162our @ISA; 1170our @ISA;
1163 1171
1164our @REGISTRY; 1172our @REGISTRY;
1165 1173
1166our $VERBOSE; 1174our $VERBOSE;
1167 1175
1168BEGIN { 1176BEGIN {
1169 eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }"; 1177 require "AnyEvent/constants.pl";
1178
1170 eval "sub TAINT(){ " . (${^TAINT}*1) . " }"; 1179 eval "sub TAINT (){" . (${^TAINT}*1) . "}";
1171 1180
1172 delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV} 1181 delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}
1173 if ${^TAINT}; 1182 if ${^TAINT};
1174 1183
1175 $VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1; 1184 $VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1;
1200 [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles 1209 [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
1201 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program 1210 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program
1202 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza 1211 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
1203 [Wx:: => AnyEvent::Impl::POE::], 1212 [Wx:: => AnyEvent::Impl::POE::],
1204 [Prima:: => AnyEvent::Impl::POE::], 1213 [Prima:: => AnyEvent::Impl::POE::],
1205 # IO::Async is just too broken - we would need workarounds for its
1206 # byzantine signal and broken child handling, among others.
1207 # IO::Async is rather hard to detect, as it doesn't have any
1208 # obvious default class.
1209 [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program
1210 [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program 1214 [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::],
1211 [IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program 1215 [Cocoa::EventLoop:: => AnyEvent::Impl::Cocoa::],
1212 [AnyEvent::Impl::IOAsync:: => AnyEvent::Impl::IOAsync::], # requires special main program
1213); 1216);
1214 1217
1215our %method = map +($_ => 1), 1218our %method = map +($_ => 1),
1216 qw(io timer time now now_update signal child idle condvar one_event DESTROY); 1219 qw(io timer time now now_update signal child idle condvar one_event DESTROY);
1217 1220
1218our @post_detect; 1221our @post_detect;
1219 1222
1220sub post_detect(&) { 1223sub post_detect(&) {
1221 my ($cb) = @_; 1224 my ($cb) = @_;
1222 1225
1223 if ($MODEL) {
1224 $cb->();
1225
1226 undef
1227 } else {
1228 push @post_detect, $cb; 1226 push @post_detect, $cb;
1229 1227
1230 defined wantarray 1228 defined wantarray
1231 ? bless \$cb, "AnyEvent::Util::postdetect" 1229 ? bless \$cb, "AnyEvent::Util::postdetect"
1232 : () 1230 : ()
1233 }
1234} 1231}
1235 1232
1236sub AnyEvent::Util::postdetect::DESTROY { 1233sub AnyEvent::Util::postdetect::DESTROY {
1237 @post_detect = grep $_ != ${$_[0]}, @post_detect; 1234 @post_detect = grep $_ != ${$_[0]}, @post_detect;
1238} 1235}
1239 1236
1240sub detect() { 1237sub detect() {
1238 # free some memory
1239 *detect = sub () { $MODEL };
1240
1241 local $!; # for good measure
1242 local $SIG{__DIE__};
1243
1244 if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {
1245 my $model = "AnyEvent::Impl::$1";
1246 if (eval "require $model") {
1247 $MODEL = $model;
1248 warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2;
1249 } else {
1250 warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE;
1251 }
1252 }
1253
1254 # check for already loaded models
1241 unless ($MODEL) { 1255 unless ($MODEL) {
1242 local $SIG{__DIE__}; 1256 for (@REGISTRY, @models) {
1243 1257 my ($package, $model) = @$_;
1244 if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) { 1258 if (${"$package\::VERSION"} > 0) {
1245 my $model = "AnyEvent::Impl::$1";
1246 if (eval "require $model") { 1259 if (eval "require $model") {
1247 $MODEL = $model; 1260 $MODEL = $model;
1248 warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2; 1261 warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2;
1249 } else { 1262 last;
1250 warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE; 1263 }
1251 } 1264 }
1252 } 1265 }
1253 1266
1254 # check for already loaded models
1255 unless ($MODEL) { 1267 unless ($MODEL) {
1268 # try to autoload a model
1256 for (@REGISTRY, @models) { 1269 for (@REGISTRY, @models) {
1257 my ($package, $model) = @$_; 1270 my ($package, $model, $autoload) = @$_;
1271 if (
1272 $autoload
1273 and eval "require $package"
1258 if (${"$package\::VERSION"} > 0) { 1274 and ${"$package\::VERSION"} > 0
1259 if (eval "require $model") { 1275 and eval "require $model"
1276 ) {
1260 $MODEL = $model; 1277 $MODEL = $model;
1261 warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2; 1278 warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2;
1262 last; 1279 last;
1263 }
1264 } 1280 }
1265 } 1281 }
1266 1282
1267 unless ($MODEL) {
1268 # try to autoload a model
1269 for (@REGISTRY, @models) {
1270 my ($package, $model, $autoload) = @$_;
1271 if (
1272 $autoload
1273 and eval "require $package"
1274 and ${"$package\::VERSION"} > 0
1275 and eval "require $model"
1276 ) {
1277 $MODEL = $model;
1278 warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2;
1279 last;
1280 }
1281 }
1282
1283 $MODEL 1283 $MODEL
1284 or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.\n"; 1284 or die "AnyEvent: backend autodetection failed - did you properly install AnyEvent?\n";
1285 }
1286 } 1285 }
1287
1288 push @{"$MODEL\::ISA"}, "AnyEvent::Base";
1289
1290 unshift @ISA, $MODEL;
1291
1292 require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT};
1293
1294 (shift @post_detect)->() while @post_detect;
1295 } 1286 }
1287
1288 @models = (); # free probe data
1289
1290 push @{"$MODEL\::ISA"}, "AnyEvent::Base";
1291 unshift @ISA, $MODEL;
1292
1293 # now nuke some methods that are overridden by the backend.
1294 # SUPER is not allowed.
1295 for (qw(time signal child idle)) {
1296 undef &{"AnyEvent::Base::$_"}
1297 if defined &{"$MODEL\::$_"};
1298 }
1299
1300 if ($ENV{PERL_ANYEVENT_STRICT}) {
1301 eval { require AnyEvent::Strict };
1302 warn "AnyEvent: cannot load AnyEvent::Strict: $@"
1303 if $@ && $VERBOSE;
1304 }
1305
1306 (shift @post_detect)->() while @post_detect;
1307
1308 *post_detect = sub(&) {
1309 shift->();
1310
1311 undef
1312 };
1296 1313
1297 $MODEL 1314 $MODEL
1298} 1315}
1299 1316
1300sub AUTOLOAD { 1317sub AUTOLOAD {
1301 (my $func = $AUTOLOAD) =~ s/.*://; 1318 (my $func = $AUTOLOAD) =~ s/.*://;
1302 1319
1303 $method{$func} 1320 $method{$func}
1304 or Carp::croak "$func: not a valid method for AnyEvent objects"; 1321 or Carp::croak "$func: not a valid AnyEvent class method";
1305 1322
1306 detect unless $MODEL; 1323 detect;
1307 1324
1308 my $class = shift; 1325 my $class = shift;
1309 $class->$func (@_); 1326 $class->$func (@_);
1310} 1327}
1311 1328
1328 1345
1329=head1 SIMPLIFIED AE API 1346=head1 SIMPLIFIED AE API
1330 1347
1331Starting with version 5.0, AnyEvent officially supports a second, much 1348Starting with version 5.0, AnyEvent officially supports a second, much
1332simpler, API that is designed to reduce the calling, typing and memory 1349simpler, API that is designed to reduce the calling, typing and memory
1333overhead. 1350overhead by using function call syntax and a fixed number of parameters.
1334 1351
1335See the L<AE> manpage for details. 1352See the L<AE> manpage for details.
1336 1353
1337=cut 1354=cut
1338 1355
1339package AE; 1356package AE;
1340 1357
1341our $VERSION = $AnyEvent::VERSION; 1358our $VERSION = $AnyEvent::VERSION;
1359
1360# fall back to the main API by default - backends and AnyEvent::Base
1361# implementations can overwrite these.
1342 1362
1343sub io($$$) { 1363sub io($$$) {
1344 AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2]) 1364 AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])
1345} 1365}
1346 1366
1378 1398
1379package AnyEvent::Base; 1399package AnyEvent::Base;
1380 1400
1381# default implementations for many methods 1401# default implementations for many methods
1382 1402
1383sub _time() { 1403sub time {
1404 eval q{ # poor man's autoloading {}
1384 # probe for availability of Time::HiRes 1405 # probe for availability of Time::HiRes
1385 if (eval "use Time::HiRes (); Time::HiRes::time (); 1") { 1406 if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
1386 warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8; 1407 warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8;
1387 *_time = \&Time::HiRes::time; 1408 *AE::time = \&Time::HiRes::time;
1388 # if (eval "use POSIX (); (POSIX::times())... 1409 # if (eval "use POSIX (); (POSIX::times())...
1389 } else { 1410 } else {
1390 warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE; 1411 warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE;
1391 *_time = sub { time }; # epic fail 1412 *AE::time = sub (){ time }; # epic fail
1413 }
1414
1415 *time = sub { AE::time }; # different prototypes
1392 } 1416 };
1417 die if $@;
1393 1418
1394 &_time 1419 &time
1395} 1420}
1396 1421
1397sub time { _time } 1422*now = \&time;
1398sub now { _time } 1423
1399sub now_update { } 1424sub now_update { }
1400 1425
1401# default implementation for ->condvar 1426# default implementation for ->condvar
1402 1427
1403sub condvar { 1428sub condvar {
1429 eval q{ # poor man's autoloading {}
1430 *condvar = sub {
1404 bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar" 1431 bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"
1432 };
1433
1434 *AE::cv = sub (;&) {
1435 bless { @_ ? (_ae_cb => shift) : () }, "AnyEvent::CondVar"
1436 };
1437 };
1438 die if $@;
1439
1440 &condvar
1405} 1441}
1406 1442
1407# default implementation for ->signal 1443# default implementation for ->signal
1408 1444
1409our $HAVE_ASYNC_INTERRUPT; 1445our $HAVE_ASYNC_INTERRUPT;
1418 1454
1419our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO); 1455our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);
1420our (%SIG_ASY, %SIG_ASY_W); 1456our (%SIG_ASY, %SIG_ASY_W);
1421our ($SIG_COUNT, $SIG_TW); 1457our ($SIG_COUNT, $SIG_TW);
1422 1458
1423sub _signal_exec {
1424 $HAVE_ASYNC_INTERRUPT
1425 ? $SIGPIPE_R->drain
1426 : sysread $SIGPIPE_R, (my $dummy), 9;
1427
1428 while (%SIG_EV) {
1429 for (keys %SIG_EV) {
1430 delete $SIG_EV{$_};
1431 $_->() for values %{ $SIG_CB{$_} || {} };
1432 }
1433 }
1434}
1435
1436# install a dummy wakeup watcher to reduce signal catching latency 1459# install a dummy wakeup watcher to reduce signal catching latency
1460# used by Impls
1437sub _sig_add() { 1461sub _sig_add() {
1438 unless ($SIG_COUNT++) { 1462 unless ($SIG_COUNT++) {
1439 # try to align timer on a full-second boundary, if possible 1463 # try to align timer on a full-second boundary, if possible
1440 my $NOW = AE::now; 1464 my $NOW = AE::now;
1441 1465
1451 undef $SIG_TW 1475 undef $SIG_TW
1452 unless --$SIG_COUNT; 1476 unless --$SIG_COUNT;
1453} 1477}
1454 1478
1455our $_sig_name_init; $_sig_name_init = sub { 1479our $_sig_name_init; $_sig_name_init = sub {
1456 eval q{ # poor man's autoloading 1480 eval q{ # poor man's autoloading {}
1457 undef $_sig_name_init; 1481 undef $_sig_name_init;
1458 1482
1459 if (_have_async_interrupt) { 1483 if (_have_async_interrupt) {
1460 *sig2num = \&Async::Interrupt::sig2num; 1484 *sig2num = \&Async::Interrupt::sig2num;
1461 *sig2name = \&Async::Interrupt::sig2name; 1485 *sig2name = \&Async::Interrupt::sig2name;
1493 $SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec; 1517 $SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;
1494 1518
1495 } else { 1519 } else {
1496 warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8; 1520 warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;
1497 1521
1498 require Fcntl;
1499
1500 if (AnyEvent::WIN32) { 1522 if (AnyEvent::WIN32) {
1501 require AnyEvent::Util; 1523 require AnyEvent::Util;
1502 1524
1503 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe (); 1525 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
1504 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R; 1526 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R;
1505 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case 1527 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case
1506 } else { 1528 } else {
1507 pipe $SIGPIPE_R, $SIGPIPE_W; 1529 pipe $SIGPIPE_R, $SIGPIPE_W;
1508 fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R; 1530 fcntl $SIGPIPE_R, AnyEvent::F_SETFL, AnyEvent::O_NONBLOCK if $SIGPIPE_R;
1509 fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case 1531 fcntl $SIGPIPE_W, AnyEvent::F_SETFL, AnyEvent::O_NONBLOCK if $SIGPIPE_W; # just in case
1510 1532
1511 # not strictly required, as $^F is normally 2, but let's make sure... 1533 # not strictly required, as $^F is normally 2, but let's make sure...
1512 fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; 1534 fcntl $SIGPIPE_R, AnyEvent::F_SETFD, AnyEvent::FD_CLOEXEC;
1513 fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; 1535 fcntl $SIGPIPE_W, AnyEvent::F_SETFD, AnyEvent::FD_CLOEXEC;
1514 } 1536 }
1515 1537
1516 $SIGPIPE_R 1538 $SIGPIPE_R
1517 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n"; 1539 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1518 1540
1519 $SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec; 1541 $SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec;
1520 } 1542 }
1521 1543
1522 *signal = sub { 1544 *signal = $HAVE_ASYNC_INTERRUPT
1545 ? sub {
1523 my (undef, %arg) = @_; 1546 my (undef, %arg) = @_;
1524 1547
1525 my $signal = uc $arg{signal}
1526 or Carp::croak "required option 'signal' is missing";
1527
1528 if ($HAVE_ASYNC_INTERRUPT) {
1529 # async::interrupt 1548 # async::interrupt
1530
1531 $signal = sig2num $signal; 1549 my $signal = sig2num $arg{signal};
1532 $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; 1550 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1533 1551
1534 $SIG_ASY{$signal} ||= new Async::Interrupt 1552 $SIG_ASY{$signal} ||= new Async::Interrupt
1535 cb => sub { undef $SIG_EV{$signal} }, 1553 cb => sub { undef $SIG_EV{$signal} },
1536 signal => $signal, 1554 signal => $signal,
1537 pipe => [$SIGPIPE_R->filenos], 1555 pipe => [$SIGPIPE_R->filenos],
1538 pipe_autodrain => 0, 1556 pipe_autodrain => 0,
1539 ; 1557 ;
1540 1558
1541 } else { 1559 bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1560 }
1561 : sub {
1562 my (undef, %arg) = @_;
1563
1542 # pure perl 1564 # pure perl
1543
1544 # AE::Util has been loaded in signal
1545 $signal = sig2name $signal; 1565 my $signal = sig2name $arg{signal};
1546 $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; 1566 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1547 1567
1548 $SIG{$signal} ||= sub { 1568 $SIG{$signal} ||= sub {
1549 local $!; 1569 local $!;
1550 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV; 1570 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
1551 undef $SIG_EV{$signal}; 1571 undef $SIG_EV{$signal};
1552 }; 1572 };
1553 1573
1554 # can't do signal processing without introducing races in pure perl, 1574 # can't do signal processing without introducing races in pure perl,
1555 # so limit the signal latency. 1575 # so limit the signal latency.
1556 _sig_add; 1576 _sig_add;
1557 }
1558 1577
1559 bless [$signal, $arg{cb}], "AnyEvent::Base::signal" 1578 bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1579 }
1560 }; 1580 ;
1561 1581
1562 *AnyEvent::Base::signal::DESTROY = sub { 1582 *AnyEvent::Base::signal::DESTROY = sub {
1563 my ($signal, $cb) = @{$_[0]}; 1583 my ($signal, $cb) = @{$_[0]};
1564 1584
1565 _sig_del; 1585 _sig_del;
1572 # print weird messages, or just unconditionally exit 1592 # print weird messages, or just unconditionally exit
1573 # instead of getting the default action. 1593 # instead of getting the default action.
1574 undef $SIG{$signal} 1594 undef $SIG{$signal}
1575 unless keys %{ $SIG_CB{$signal} }; 1595 unless keys %{ $SIG_CB{$signal} };
1576 }; 1596 };
1597
1598 *_signal_exec = sub {
1599 $HAVE_ASYNC_INTERRUPT
1600 ? $SIGPIPE_R->drain
1601 : sysread $SIGPIPE_R, (my $dummy), 9;
1602
1603 while (%SIG_EV) {
1604 for (keys %SIG_EV) {
1605 delete $SIG_EV{$_};
1606 $_->() for values %{ $SIG_CB{$_} || {} };
1607 }
1608 }
1609 };
1577 }; 1610 };
1578 die if $@; 1611 die if $@;
1612
1579 &signal 1613 &signal
1580} 1614}
1581 1615
1582# default implementation for ->child 1616# default implementation for ->child
1583 1617
1584our %PID_CB; 1618our %PID_CB;
1585our $CHLD_W; 1619our $CHLD_W;
1586our $CHLD_DELAY_W; 1620our $CHLD_DELAY_W;
1587our $WNOHANG;
1588 1621
1622# used by many Impl's
1589sub _emit_childstatus($$) { 1623sub _emit_childstatus($$) {
1590 my (undef, $rpid, $rstatus) = @_; 1624 my (undef, $rpid, $rstatus) = @_;
1591 1625
1592 $_->($rpid, $rstatus) 1626 $_->($rpid, $rstatus)
1593 for values %{ $PID_CB{$rpid} || {} }, 1627 for values %{ $PID_CB{$rpid} || {} },
1594 values %{ $PID_CB{0} || {} }; 1628 values %{ $PID_CB{0} || {} };
1595} 1629}
1596 1630
1597sub _sigchld {
1598 my $pid;
1599
1600 AnyEvent->_emit_childstatus ($pid, $?)
1601 while ($pid = waitpid -1, $WNOHANG) > 0;
1602}
1603
1604sub child { 1631sub child {
1632 eval q{ # poor man's autoloading {}
1633 *_sigchld = sub {
1634 my $pid;
1635
1636 AnyEvent->_emit_childstatus ($pid, $?)
1637 while ($pid = waitpid -1, WNOHANG) > 0;
1638 };
1639
1640 *child = sub {
1605 my (undef, %arg) = @_; 1641 my (undef, %arg) = @_;
1606 1642
1607 defined (my $pid = $arg{pid} + 0) 1643 defined (my $pid = $arg{pid} + 0)
1608 or Carp::croak "required option 'pid' is missing"; 1644 or Carp::croak "required option 'pid' is missing";
1609 1645
1610 $PID_CB{$pid}{$arg{cb}} = $arg{cb}; 1646 $PID_CB{$pid}{$arg{cb}} = $arg{cb};
1611 1647
1612 # WNOHANG is almost cetrainly 1 everywhere
1613 $WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/
1614 ? 1
1615 : eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1;
1616
1617 unless ($CHLD_W) { 1648 unless ($CHLD_W) {
1618 $CHLD_W = AE::signal CHLD => \&_sigchld; 1649 $CHLD_W = AE::signal CHLD => \&_sigchld;
1619 # child could be a zombie already, so make at least one round 1650 # child could be a zombie already, so make at least one round
1620 &_sigchld; 1651 &_sigchld;
1621 } 1652 }
1622 1653
1623 bless [$pid, $arg{cb}], "AnyEvent::Base::child" 1654 bless [$pid, $arg{cb}], "AnyEvent::Base::child"
1624} 1655 };
1625 1656
1626sub AnyEvent::Base::child::DESTROY { 1657 *AnyEvent::Base::child::DESTROY = sub {
1627 my ($pid, $cb) = @{$_[0]}; 1658 my ($pid, $cb) = @{$_[0]};
1628 1659
1629 delete $PID_CB{$pid}{$cb}; 1660 delete $PID_CB{$pid}{$cb};
1630 delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} }; 1661 delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };
1631 1662
1632 undef $CHLD_W unless keys %PID_CB; 1663 undef $CHLD_W unless keys %PID_CB;
1664 };
1665 };
1666 die if $@;
1667
1668 &child
1633} 1669}
1634 1670
1635# idle emulation is done by simply using a timer, regardless 1671# idle emulation is done by simply using a timer, regardless
1636# of whether the process is idle or not, and not letting 1672# of whether the process is idle or not, and not letting
1637# the callback use more than 50% of the time. 1673# the callback use more than 50% of the time.
1638sub idle { 1674sub idle {
1675 eval q{ # poor man's autoloading {}
1676 *idle = sub {
1639 my (undef, %arg) = @_; 1677 my (undef, %arg) = @_;
1640 1678
1641 my ($cb, $w, $rcb) = $arg{cb}; 1679 my ($cb, $w, $rcb) = $arg{cb};
1642 1680
1643 $rcb = sub { 1681 $rcb = sub {
1644 if ($cb) { 1682 if ($cb) {
1645 $w = _time; 1683 $w = _time;
1646 &$cb; 1684 &$cb;
1647 $w = _time - $w; 1685 $w = _time - $w;
1648 1686
1649 # never use more then 50% of the time for the idle watcher, 1687 # never use more then 50% of the time for the idle watcher,
1650 # within some limits 1688 # within some limits
1651 $w = 0.0001 if $w < 0.0001; 1689 $w = 0.0001 if $w < 0.0001;
1652 $w = 5 if $w > 5; 1690 $w = 5 if $w > 5;
1653 1691
1654 $w = AE::timer $w, 0, $rcb; 1692 $w = AE::timer $w, 0, $rcb;
1655 } else { 1693 } else {
1656 # clean up... 1694 # clean up...
1657 undef $w; 1695 undef $w;
1658 undef $rcb; 1696 undef $rcb;
1697 }
1698 };
1699
1700 $w = AE::timer 0.05, 0, $rcb;
1701
1702 bless \\$cb, "AnyEvent::Base::idle"
1659 } 1703 };
1704
1705 *AnyEvent::Base::idle::DESTROY = sub {
1706 undef $${$_[0]};
1707 };
1660 }; 1708 };
1709 die if $@;
1661 1710
1662 $w = AE::timer 0.05, 0, $rcb; 1711 &idle
1663
1664 bless \\$cb, "AnyEvent::Base::idle"
1665}
1666
1667sub AnyEvent::Base::idle::DESTROY {
1668 undef $${$_[0]};
1669} 1712}
1670 1713
1671package AnyEvent::CondVar; 1714package AnyEvent::CondVar;
1672 1715
1673our @ISA = AnyEvent::CondVar::Base::; 1716our @ISA = AnyEvent::CondVar::Base::;
1717
1718# only to be used for subclassing
1719sub new {
1720 my $class = shift;
1721 bless AnyEvent->condvar (@_), $class
1722}
1674 1723
1675package AnyEvent::CondVar::Base; 1724package AnyEvent::CondVar::Base;
1676 1725
1677#use overload 1726#use overload
1678# '&{}' => sub { my $self = shift; sub { $self->send (@_) } }, 1727# '&{}' => sub { my $self = shift; sub { $self->send (@_) } },
1800check the arguments passed to most method calls. If it finds any problems, 1849check the arguments passed to most method calls. If it finds any problems,
1801it will croak. 1850it will croak.
1802 1851
1803In other words, enables "strict" mode. 1852In other words, enables "strict" mode.
1804 1853
1805Unlike C<use strict> (or it's modern cousin, C<< use L<common::sense> 1854Unlike C<use strict> (or its modern cousin, C<< use L<common::sense>
1806>>, it is definitely recommended to keep it off in production. Keeping 1855>>, it is definitely recommended to keep it off in production. Keeping
1807C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs 1856C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs
1808can be very useful, however. 1857can be very useful, however.
1809 1858
1810=item C<PERL_ANYEVENT_MODEL> 1859=item C<PERL_ANYEVENT_MODEL>
2032 2081
2033The actual code goes further and collects all errors (C<die>s, exceptions) 2082The actual code goes further and collects all errors (C<die>s, exceptions)
2034that occurred during request processing. The C<result> method detects 2083that occurred during request processing. The C<result> method detects
2035whether an exception as thrown (it is stored inside the $txn object) 2084whether an exception as thrown (it is stored inside the $txn object)
2036and just throws the exception, which means connection errors and other 2085and just throws the exception, which means connection errors and other
2037problems get reported tot he code that tries to use the result, not in a 2086problems get reported to the code that tries to use the result, not in a
2038random callback. 2087random callback.
2039 2088
2040All of this enables the following usage styles: 2089All of this enables the following usage styles:
2041 2090
20421. Blocking: 20911. Blocking:
2456 unless defined $SIG{PIPE}; 2505 unless defined $SIG{PIPE};
2457 2506
2458=head1 RECOMMENDED/OPTIONAL MODULES 2507=head1 RECOMMENDED/OPTIONAL MODULES
2459 2508
2460One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and 2509One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and
2461it's built-in modules) are required to use it. 2510its built-in modules) are required to use it.
2462 2511
2463That does not mean that AnyEvent won't take advantage of some additional 2512That does not mean that AnyEvent won't take advantage of some additional
2464modules if they are installed. 2513modules if they are installed.
2465 2514
2466This section explains which additional modules will be used, and how they 2515This section explains which additional modules will be used, and how they
2499automatic timer adjustments even when no monotonic clock is available, 2548automatic timer adjustments even when no monotonic clock is available,
2500can take avdantage of advanced kernel interfaces such as C<epoll> and 2549can take avdantage of advanced kernel interfaces such as C<epoll> and
2501C<kqueue>, and is the fastest backend I<by far>. You can even embed 2550C<kqueue>, and is the fastest backend I<by far>. You can even embed
2502L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>). 2551L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>).
2503 2552
2553If you only use backends that rely on another event loop (e.g. C<Tk>),
2554then this module will do nothing for you.
2555
2504=item L<Guard> 2556=item L<Guard>
2505 2557
2506The guard module, when used, will be used to implement 2558The guard module, when used, will be used to implement
2507C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a 2559C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a
2508lot less memory), but otherwise doesn't affect guard operation much. It is 2560lot less memory), but otherwise doesn't affect guard operation much. It is
2509purely used for performance. 2561purely used for performance.
2510 2562
2511=item L<JSON> and L<JSON::XS> 2563=item L<JSON> and L<JSON::XS>
2512 2564
2513One of these modules is required when you want to read or write JSON data 2565One of these modules is required when you want to read or write JSON data
2514via L<AnyEvent::Handle>. It is also written in pure-perl, but can take 2566via L<AnyEvent::Handle>. L<JSON> is also written in pure-perl, but can take
2515advantage of the ultra-high-speed L<JSON::XS> module when it is installed. 2567advantage of the ultra-high-speed L<JSON::XS> module when it is installed.
2516
2517In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is
2518installed.
2519 2568
2520=item L<Net::SSLeay> 2569=item L<Net::SSLeay>
2521 2570
2522Implementing TLS/SSL in Perl is certainly interesting, but not very 2571Implementing TLS/SSL in Perl is certainly interesting, but not very
2523worthwhile: If this module is installed, then L<AnyEvent::Handle> (with 2572worthwhile: If this module is installed, then L<AnyEvent::Handle> (with
2524the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL. 2573the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL.
2525 2574
2526=item L<Time::HiRes> 2575=item L<Time::HiRes>
2527 2576
2528This module is part of perl since release 5.008. It will be used when the 2577This module is part of perl since release 5.008. It will be used when the
2529chosen event library does not come with a timing source on it's own. The 2578chosen event library does not come with a timing source of its own. The
2530pure-perl event loop (L<AnyEvent::Impl::Perl>) will additionally use it to 2579pure-perl event loop (L<AnyEvent::Impl::Perl>) will additionally use it to
2531try to use a monotonic clock for timing stability. 2580try to use a monotonic clock for timing stability.
2532 2581
2533=back 2582=back
2534 2583
2535 2584
2536=head1 FORK 2585=head1 FORK
2537 2586
2538Most event libraries are not fork-safe. The ones who are usually are 2587Most event libraries are not fork-safe. The ones who are usually are
2539because they rely on inefficient but fork-safe C<select> or C<poll> 2588because they rely on inefficient but fork-safe C<select> or C<poll> calls
2540calls. Only L<EV> is fully fork-aware. 2589- higher performance APIs such as BSD's kqueue or the dreaded Linux epoll
2590are usually badly thought-out hacks that are incompatible with fork in
2591one way or another. Only L<EV> is fully fork-aware and ensures that you
2592continue event-processing in both parent and child (or both, if you know
2593what you are doing).
2541 2594
2542This means that, in general, you cannot fork and do event processing 2595This means that, in general, you cannot fork and do event processing in
2543in the child if a watcher was created before the fork (which in turn 2596the child if the event library was initialised before the fork (which
2544initialises the event library). 2597usually happens when the first AnyEvent watcher is created, or the library
2598is loaded).
2545 2599
2546If you have to fork, you must either do so I<before> creating your first 2600If you have to fork, you must either do so I<before> creating your first
2547watcher OR you must not use AnyEvent at all in the child OR you must do 2601watcher OR you must not use AnyEvent at all in the child OR you must do
2548something completely out of the scope of AnyEvent. 2602something completely out of the scope of AnyEvent.
2549 2603
2550The problem of doing event processing in the parent I<and> the child 2604The problem of doing event processing in the parent I<and> the child
2551is much more complicated: even for backends that I<are> fork-aware or 2605is much more complicated: even for backends that I<are> fork-aware or
2552fork-safe, their behaviour is not usually what you want: fork clones all 2606fork-safe, their behaviour is not usually what you want: fork clones all
2553watchers, that means all timers, I/O watchers etc. are active in both 2607watchers, that means all timers, I/O watchers etc. are active in both
2554parent and child, which is almost never what you want. 2608parent and child, which is almost never what you want. USing C<exec>
2609to start worker children from some kind of manage rprocess is usually
2610preferred, because it is much easier and cleaner, at the expense of having
2611to have another binary.
2555 2612
2556 2613
2557=head1 SECURITY CONSIDERATIONS 2614=head1 SECURITY CONSIDERATIONS
2558 2615
2559AnyEvent can be forced to load any event model via 2616AnyEvent can be forced to load any event model via
2589pronounced). 2646pronounced).
2590 2647
2591 2648
2592=head1 SEE ALSO 2649=head1 SEE ALSO
2593 2650
2651Tutorial/Introduction: L<AnyEvent::Intro>.
2652
2653FAQ: L<AnyEvent::FAQ>.
2654
2594Utility functions: L<AnyEvent::Util>. 2655Utility functions: L<AnyEvent::Util>.
2595 2656
2596Event modules: L<EV>, L<EV::Glib>, L<Glib::EV>, L<Event>, L<Glib::Event>, 2657Event modules: L<EV>, L<EV::Glib>, L<Glib::EV>, L<Event>, L<Glib::Event>,
2597L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. 2658L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.
2598 2659
2604Non-blocking file handles, sockets, TCP clients and 2665Non-blocking file handles, sockets, TCP clients and
2605servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>. 2666servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.
2606 2667
2607Asynchronous DNS: L<AnyEvent::DNS>. 2668Asynchronous DNS: L<AnyEvent::DNS>.
2608 2669
2609Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, 2670Thread support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>.
2610L<Coro::Event>,
2611 2671
2612Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::XMPP>, 2672Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::IRC>,
2613L<AnyEvent::HTTP>. 2673L<AnyEvent::HTTP>.
2614 2674
2615 2675
2616=head1 AUTHOR 2676=head1 AUTHOR
2617 2677

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