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Revision 1.337 by root, Mon Nov 22 06:32:18 2010 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 + IO::Async? No go. Tk + Event? No go. Again: if
86your module uses one of those, every user of your module has to use it, 91your module uses one of those, every user of your module has to use it,
87too. But if your module uses AnyEvent, it works transparently with all 92too. But if your module uses AnyEvent, it works transparently with all
88event models it supports (including stuff like IO::Async, as long as those 93event models it supports (including stuff like IO::Async, as long as those
89use one of the supported event loops. It is trivial to add new event loops 94use one of the supported event loops. It is easy to add new event loops
90to AnyEvent, too, so it is future-proof). 95to AnyEvent, too, so 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
363might affect timers and time-outs. 367might affect timers and time-outs.
364 368
365When this is the case, you can call this method, which will update the 369When this is the case, you can call this method, which will update the
366event loop's idea of "current time". 370event loop's idea of "current time".
367 371
372A typical example would be a script in a web server (e.g. C<mod_perl>) -
373when mod_perl executes the script, then the event loop will have the wrong
374idea about the "current time" (being potentially far in the past, when the
375script ran the last time). In that case you should arrange a call to C<<
376AnyEvent->now_update >> each time the web server process wakes up again
377(e.g. at the start of your script, or in a handler).
378
368Note that updating the time I<might> cause some events to be handled. 379Note that updating the time I<might> cause some events to be handled.
369 380
370=back 381=back
371 382
372=head2 SIGNAL WATCHERS 383=head2 SIGNAL WATCHERS
396 407
397Example: exit on SIGINT 408Example: exit on SIGINT
398 409
399 my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 }); 410 my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
400 411
412=head3 Restart Behaviour
413
414While restart behaviour is up to the event loop implementation, most will
415not restart syscalls (that includes L<Async::Interrupt> and AnyEvent's
416pure perl implementation).
417
418=head3 Safe/Unsafe Signals
419
420Perl signals can be either "safe" (synchronous to opcode handling) or
421"unsafe" (asynchronous) - the former might get delayed indefinitely, the
422latter might corrupt your memory.
423
424AnyEvent signal handlers are, in addition, synchronous to the event loop,
425i.e. they will not interrupt your running perl program but will only be
426called as part of the normal event handling (just like timer, I/O etc.
427callbacks, too).
428
401=head3 Signal Races, Delays and Workarounds 429=head3 Signal Races, Delays and Workarounds
402 430
403Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching 431Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching
404callbacks to signals in a generic way, which is a pity, as you cannot 432callbacks to signals in a generic way, which is a pity, as you cannot
405do race-free signal handling in perl, requiring C libraries for 433do race-free signal handling in perl, requiring C libraries for
406this. AnyEvent will try to do it's best, which means in some cases, 434this. AnyEvent will try to do its best, which means in some cases,
407signals will be delayed. The maximum time a signal might be delayed is 435signals will be delayed. The maximum time a signal might be delayed is
408specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This 436specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This
409variable can be changed only before the first signal watcher is created, 437variable can be changed only before the first signal watcher is created,
410and should be left alone otherwise. This variable determines how often 438and should be left alone otherwise. This variable determines how often
411AnyEvent 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
413saving. 441saving.
414 442
415All these problems can be avoided by installing the optional 443All these problems can be avoided by installing the optional
416L<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
417work 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>
418(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
419one-second latency). For those, you just have to suffer the delays. 447one-second latency). For those, you just have to suffer the delays.
420 448
421=head2 CHILD PROCESS WATCHERS 449=head2 CHILD PROCESS WATCHERS
422 450
423 $w = AnyEvent->child (pid => <process id>, cb => <callback>); 451 $w = AnyEvent->child (pid => <process id>, cb => <callback>);
424 452
425You 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.
426 454
427The 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,
428using 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
429croak). The watcher will be triggered only when the child process has 457croak). The watcher will be triggered only when the child process has
430finished and an exit status is available, not on any trace events 458finished and an exit status is available, not on any trace events
431(stopped/continued). 459(stopped/continued).
432 460
479 507
480=head2 IDLE WATCHERS 508=head2 IDLE WATCHERS
481 509
482 $w = AnyEvent->idle (cb => <callback>); 510 $w = AnyEvent->idle (cb => <callback>);
483 511
484Sometimes there is a need to do something, but it is not so important 512This will repeatedly invoke the callback after the process becomes idle,
485to 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.
486"nothing better to do" is usually defined to be "no other events need
487attention by the event loop".
488 514
489Idle watchers ideally get invoked when the event loop has nothing 515Idle watchers are useful when there is a need to do something, but it
490better 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
491events. 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.
492 523
493Most event loops unfortunately do not really support idle watchers (only 524Unfortunately, most event loops do not really support idle watchers (only
494EV, 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
495will simply call the callback "from time to time". 526will simply call the callback "from time to time".
496 527
497Example: read lines from STDIN, but only process them when the 528Example: read lines from STDIN, but only process them when the
498program is otherwise idle: 529program is otherwise idle:
526will actively watch for new events and call your callbacks. 557will actively watch for new events and call your callbacks.
527 558
528AnyEvent is slightly different: it expects somebody else to run the event 559AnyEvent is slightly different: it expects somebody else to run the event
529loop 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).
530 561
531The instrument to do that is called a "condition variable", so called 562The tool to do that is called a "condition variable", so called because
532because they represent a condition that must become true. 563they represent a condition that must become true.
533 564
534Now 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.
535 566
536Condition variables can be created by calling the C<< AnyEvent->condvar 567Condition variables can be created by calling the C<< AnyEvent->condvar
537>> method, usually without arguments. The only argument pair allowed is 568>> method, usually without arguments. The only argument pair allowed is
542After creation, the condition variable is "false" until it becomes "true" 573After creation, the condition variable is "false" until it becomes "true"
543by 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
544were 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<<
545->send >> method). 576->send >> method).
546 577
547Condition variables are similar to callbacks, except that you can 578Since condition variables are the most complex part of the AnyEvent API, here are
548optionally 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:
549in time where multiple outstanding events have been processed. And yet 580
550another way to call them is transactions - each condition variable can be 581=over 4
551used to represent a transaction, which finishes at some point and delivers 582
552a 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
553compute/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
554 601
555Condition variables are very useful to signal that something has finished, 602Condition variables are very useful to signal that something has finished,
556for example, if you write a module that does asynchronous http requests, 603for example, if you write a module that does asynchronous http requests,
557then a condition variable would be the ideal candidate to signal the 604then a condition variable would be the ideal candidate to signal the
558availability of results. The user can either act when the callback is 605availability of results. The user can either act when the callback is
571 618
572Condition variables are represented by hash refs in perl, and the keys 619Condition variables are represented by hash refs in perl, and the keys
573used 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
574easy (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
575AnyEvent). To subclass, use C<AnyEvent::CondVar> as base class and call 622AnyEvent). To subclass, use C<AnyEvent::CondVar> as base class and call
576it's C<new> method in your own C<new> method. 623its C<new> method in your own C<new> method.
577 624
578There are two "sides" to a condition variable - the "producer side" which 625There are two "sides" to a condition variable - the "producer side" which
579eventually calls C<< -> send >>, and the "consumer side", which waits 626eventually calls C<< -> send >>, and the "consumer side", which waits
580for the send to occur. 627for the send to occur.
581 628
582Example: wait for a timer. 629Example: wait for a timer.
583 630
584 # wait till the result is ready 631 # condition: "wait till the timer is fired"
585 my $result_ready = AnyEvent->condvar; 632 my $timer_fired = AnyEvent->condvar;
586 633
587 # do something such as adding a timer 634 # create the timer - we could wait for, say
588 # or socket watcher the calls $result_ready->send 635 # a handle becomign ready, or even an
589 # when the "result" is ready. 636 # AnyEvent::HTTP request to finish, but
590 # in this case, we simply use a timer: 637 # in this case, we simply use a timer:
591 my $w = AnyEvent->timer ( 638 my $w = AnyEvent->timer (
592 after => 1, 639 after => 1,
593 cb => sub { $result_ready->send }, 640 cb => sub { $timer_fired->send },
594 ); 641 );
595 642
596 # this "blocks" (while handling events) till the callback 643 # this "blocks" (while handling events) till the callback
597 # calls ->send 644 # calls ->send
598 $result_ready->recv; 645 $timer_fired->recv;
599 646
600Example: 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
601variables are also callable directly. 648variables are also callable directly.
602 649
603 my $done = AnyEvent->condvar; 650 my $done = AnyEvent->condvar;
646they 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
647C<send>. 694C<send>.
648 695
649=item $cv->croak ($error) 696=item $cv->croak ($error)
650 697
651Similar to send, but causes all call's to C<< ->recv >> to invoke 698Similar to send, but causes all calls to C<< ->recv >> to invoke
652C<Carp::croak> with the given error message/object/scalar. 699C<Carp::croak> with the given error message/object/scalar.
653 700
654This can be used to signal any errors to the condition variable 701This can be used to signal any errors to the condition variable
655user/consumer. Doing it this way instead of calling C<croak> directly 702user/consumer. Doing it this way instead of calling C<croak> directly
656delays the error detetcion, but has the overwhelmign advantage that it 703delays the error detection, but has the overwhelming advantage that it
657diagnoses 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
658deep in some event clalback without connection to the actual code causing 705deep in some event callback with no connection to the actual code causing
659the problem. 706the problem.
660 707
661=item $cv->begin ([group callback]) 708=item $cv->begin ([group callback])
662 709
663=item $cv->end 710=item $cv->end
701one 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
702sending. 749sending.
703 750
704The ping example mentioned above is slightly more complicated, as the 751The ping example mentioned above is slightly more complicated, as the
705there 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
706begung can potentially be zero: 753begun can potentially be zero:
707 754
708 my $cv = AnyEvent->condvar; 755 my $cv = AnyEvent->condvar;
709 756
710 my %result; 757 my %result;
711 $cv->begin (sub { shift->send (\%result) }); 758 $cv->begin (sub { shift->send (\%result) });
732to 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
733C<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
734doesn't execute once). 781doesn't execute once).
735 782
736This is the general pattern when you "fan out" into multiple (but 783This is the general pattern when you "fan out" into multiple (but
737potentially 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
738the 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
739subrequest you start, call C<begin> and for each subrequest you finish, 786subrequest you start, call C<begin> and for each subrequest you finish,
740call C<end>. 787call C<end>.
741 788
742=back 789=back
749=over 4 796=over 4
750 797
751=item $cv->recv 798=item $cv->recv
752 799
753Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak 800Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak
754>> methods have been called on c<$cv>, while servicing other watchers 801>> methods have been called on C<$cv>, while servicing other watchers
755normally. 802normally.
756 803
757You 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
758will return immediately. 805will return immediately.
759 806
776caller 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
777condition variables with some kind of request results and supporting 824condition variables with some kind of request results and supporting
778callbacks so the caller knows that getting the result will not block, 825callbacks so the caller knows that getting the result will not block,
779while still supporting blocking waits if the caller so desires). 826while still supporting blocking waits if the caller so desires).
780 827
781You 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
782only calling C<< ->recv >> from within that callback (or at a later 829only calling C<< ->recv >> from within that callback (or at a later
783time). 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
784waits otherwise. 831waits otherwise.
785 832
786=item $bool = $cv->ready 833=item $bool = $cv->ready
791=item $cb = $cv->cb ($cb->($cv)) 838=item $cb = $cv->cb ($cb->($cv))
792 839
793This is a mutator function that returns the callback set and optionally 840This is a mutator function that returns the callback set and optionally
794replaces it before doing so. 841replaces it before doing so.
795 842
796The callback will be called when the condition becomes (or already was) 843The callback will be called when the condition becomes "true", i.e. when
797"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
798the 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
799inside the callback or at any later time is guaranteed not to block. 847the callback or at any later time is guaranteed not to block.
800 848
801=back 849=back
802 850
803=head1 SUPPORTED EVENT LOOPS/BACKENDS 851=head1 SUPPORTED EVENT LOOPS/BACKENDS
804 852
816 AnyEvent::Impl::EV based on EV (interface to libev, best choice). 864 AnyEvent::Impl::EV based on EV (interface to libev, best choice).
817 AnyEvent::Impl::Perl pure-perl implementation, fast and portable. 865 AnyEvent::Impl::Perl pure-perl implementation, fast and portable.
818 866
819=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.
820 868
821These 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
822is 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
823them. This means that AnyEvent will automatically pick the right backend 871them. This means that AnyEvent will automatically pick the right backend
824when the main program loads an event module before anything starts to 872when the main program loads an event module before anything starts to
825create watchers. Nothing special needs to be done by the main program. 873create watchers. Nothing special needs to be done by the main program.
826 874
842 890
843Support for IO::Async can only be partial, as it is too broken and 891Support for IO::Async can only be partial, as it is too broken and
844architecturally limited to even support the AnyEvent API. It also 892architecturally limited to even support the AnyEvent API. It also
845is the only event loop that needs the loop to be set explicitly, so 893is the only event loop that needs the loop to be set explicitly, so
846it can only be used by a main program knowing about AnyEvent. See 894it can only be used by a main program knowing about AnyEvent. See
847L<AnyEvent::Impl::Async> for the gory details. 895L<AnyEvent::Impl::IOAsync> for the gory details.
848 896
849 AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed. 897 AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed.
850 898
851=item Event loops that are indirectly supported via other backends. 899=item Event loops that are indirectly supported via other backends.
852 900
880Contains C<undef> until the first watcher is being created, before the 928Contains C<undef> until the first watcher is being created, before the
881backend has been autodetected. 929backend has been autodetected.
882 930
883Afterwards it contains the event model that is being used, which is the 931Afterwards it contains the event model that is being used, which is the
884name of the Perl class implementing the model. This class is usually one 932name of the Perl class implementing the model. This class is usually one
885of the C<AnyEvent::Impl:xxx> modules, but can be any other class in the 933of the C<AnyEvent::Impl::xxx> modules, but can be any other class in the
886case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it 934case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it
887will be C<urxvt::anyevent>). 935will be C<urxvt::anyevent>).
888 936
889=item AnyEvent::detect 937=item AnyEvent::detect
890 938
891Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model 939Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model
892if necessary. You should only call this function right before you would 940if necessary. You should only call this function right before you would
893have created an AnyEvent watcher anyway, that is, as late as possible at 941have created an AnyEvent watcher anyway, that is, as late as possible at
894runtime, and not e.g. while initialising of your module. 942runtime, and not e.g. during initialisation of your module.
895 943
896If you need to do some initialisation before AnyEvent watchers are 944If you need to do some initialisation before AnyEvent watchers are
897created, use C<post_detect>. 945created, use C<post_detect>.
898 946
899=item $guard = AnyEvent::post_detect { BLOCK } 947=item $guard = AnyEvent::post_detect { BLOCK }
900 948
901Arranges for the code block to be executed as soon as the event model is 949Arranges for the code block to be executed as soon as the event model is
902autodetected (or immediately if this has already happened). 950autodetected (or immediately if that has already happened).
903 951
904The block will be executed I<after> the actual backend has been detected 952The block will be executed I<after> the actual backend has been detected
905(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been 953(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been
906created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do 954created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do
907other initialisations - see the sources of L<AnyEvent::Strict> or 955other initialisations - see the sources of L<AnyEvent::Strict> or
916that automatically removes the callback again when it is destroyed (or 964that automatically removes the callback again when it is destroyed (or
917C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for 965C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for
918a case where this is useful. 966a case where this is useful.
919 967
920Example: Create a watcher for the IO::AIO module and store it in 968Example: Create a watcher for the IO::AIO module and store it in
921C<$WATCHER>. Only do so after the event loop is initialised, though. 969C<$WATCHER>, but do so only do so after the event loop is initialised.
922 970
923 our WATCHER; 971 our WATCHER;
924 972
925 my $guard = AnyEvent::post_detect { 973 my $guard = AnyEvent::post_detect {
926 $WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb); 974 $WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb);
934 $WATCHER ||= $guard; 982 $WATCHER ||= $guard;
935 983
936=item @AnyEvent::post_detect 984=item @AnyEvent::post_detect
937 985
938If there are any code references in this array (you can C<push> to it 986If there are any code references in this array (you can C<push> to it
939before or after loading AnyEvent), then they will called directly after 987before or after loading AnyEvent), then they will be called directly
940the event loop has been chosen. 988after the event loop has been chosen.
941 989
942You should check C<$AnyEvent::MODEL> before adding to this array, though: 990You should check C<$AnyEvent::MODEL> before adding to this array, though:
943if it is defined then the event loop has already been detected, and the 991if it is defined then the event loop has already been detected, and the
944array will be ignored. 992array will be ignored.
945 993
946Best use C<AnyEvent::post_detect { BLOCK }> when your application allows 994Best use C<AnyEvent::post_detect { BLOCK }> when your application allows
947it,as it takes care of these details. 995it, as it takes care of these details.
948 996
949This variable is mainly useful for modules that can do something useful 997This variable is mainly useful for modules that can do something useful
950when AnyEvent is used and thus want to know when it is initialised, but do 998when AnyEvent is used and thus want to know when it is initialised, but do
951not need to even load it by default. This array provides the means to hook 999not need to even load it by default. This array provides the means to hook
952into AnyEvent passively, without loading it. 1000into AnyEvent passively, without loading it.
953 1001
1002Example: To load Coro::AnyEvent whenever Coro and AnyEvent are used
1003together, you could put this into Coro (this is the actual code used by
1004Coro to accomplish this):
1005
1006 if (defined $AnyEvent::MODEL) {
1007 # AnyEvent already initialised, so load Coro::AnyEvent
1008 require Coro::AnyEvent;
1009 } else {
1010 # AnyEvent not yet initialised, so make sure to load Coro::AnyEvent
1011 # as soon as it is
1012 push @AnyEvent::post_detect, sub { require Coro::AnyEvent };
1013 }
1014
954=back 1015=back
955 1016
956=head1 WHAT TO DO IN A MODULE 1017=head1 WHAT TO DO IN A MODULE
957 1018
958As a module author, you should C<use AnyEvent> and call AnyEvent methods 1019As a module author, you should C<use AnyEvent> and call AnyEvent methods
968because it will stall the whole program, and the whole point of using 1029because it will stall the whole program, and the whole point of using
969events is to stay interactive. 1030events is to stay interactive.
970 1031
971It is fine, however, to call C<< ->recv >> when the user of your module 1032It is fine, however, to call C<< ->recv >> when the user of your module
972requests it (i.e. if you create a http request object ad have a method 1033requests it (i.e. if you create a http request object ad have a method
973called C<results> that returns the results, it should call C<< ->recv >> 1034called C<results> that returns the results, it may call C<< ->recv >>
974freely, as the user of your module knows what she is doing. always). 1035freely, as the user of your module knows what she is doing. Always).
975 1036
976=head1 WHAT TO DO IN THE MAIN PROGRAM 1037=head1 WHAT TO DO IN THE MAIN PROGRAM
977 1038
978There will always be a single main program - the only place that should 1039There will always be a single main program - the only place that should
979dictate which event model to use. 1040dictate which event model to use.
980 1041
981If it doesn't care, it can just "use AnyEvent" and use it itself, or not 1042If the program is not event-based, it need not do anything special, even
982do anything special (it does not need to be event-based) and let AnyEvent 1043when it depends on a module that uses an AnyEvent. If the program itself
983decide which implementation to chose if some module relies on it. 1044uses AnyEvent, but does not care which event loop is used, all it needs
1045to do is C<use AnyEvent>. In either case, AnyEvent will choose the best
1046available loop implementation.
984 1047
985If the main program relies on a specific event model - for example, in 1048If the main program relies on a specific event model - for example, in
986Gtk2 programs you have to rely on the Glib module - you should load the 1049Gtk2 programs you have to rely on the Glib module - you should load the
987event module before loading AnyEvent or any module that uses it: generally 1050event module before loading AnyEvent or any module that uses it: generally
988speaking, you should load it as early as possible. The reason is that 1051speaking, you should load it as early as possible. The reason is that
989modules might create watchers when they are loaded, and AnyEvent will 1052modules might create watchers when they are loaded, and AnyEvent will
990decide on the event model to use as soon as it creates watchers, and it 1053decide on the event model to use as soon as it creates watchers, and it
991might chose the wrong one unless you load the correct one yourself. 1054might choose the wrong one unless you load the correct one yourself.
992 1055
993You can chose to use a pure-perl implementation by loading the 1056You can chose to use a pure-perl implementation by loading the
994C<AnyEvent::Impl::Perl> module, which gives you similar behaviour 1057C<AnyEvent::Impl::Perl> module, which gives you similar behaviour
995everywhere, but letting AnyEvent chose the model is generally better. 1058everywhere, but letting AnyEvent chose the model is generally better.
996 1059
1014=head1 OTHER MODULES 1077=head1 OTHER MODULES
1015 1078
1016The following is a non-exhaustive list of additional modules that use 1079The following is a non-exhaustive list of additional modules that use
1017AnyEvent as a client and can therefore be mixed easily with other AnyEvent 1080AnyEvent as a client and can therefore be mixed easily with other AnyEvent
1018modules and other event loops in the same program. Some of the modules 1081modules and other event loops in the same program. Some of the modules
1019come with AnyEvent, most are available via CPAN. 1082come as part of AnyEvent, the others are available via CPAN.
1020 1083
1021=over 4 1084=over 4
1022 1085
1023=item L<AnyEvent::Util> 1086=item L<AnyEvent::Util>
1024 1087
1025Contains various utility functions that replace often-used but blocking 1088Contains various utility functions that replace often-used blocking
1026functions such as C<inet_aton> by event-/callback-based versions. 1089functions such as C<inet_aton> with event/callback-based versions.
1027 1090
1028=item L<AnyEvent::Socket> 1091=item L<AnyEvent::Socket>
1029 1092
1030Provides various utility functions for (internet protocol) sockets, 1093Provides various utility functions for (internet protocol) sockets,
1031addresses and name resolution. Also functions to create non-blocking tcp 1094addresses and name resolution. Also functions to create non-blocking tcp
1033 1096
1034=item L<AnyEvent::Handle> 1097=item L<AnyEvent::Handle>
1035 1098
1036Provide read and write buffers, manages watchers for reads and writes, 1099Provide read and write buffers, manages watchers for reads and writes,
1037supports raw and formatted I/O, I/O queued and fully transparent and 1100supports raw and formatted I/O, I/O queued and fully transparent and
1038non-blocking SSL/TLS (via L<AnyEvent::TLS>. 1101non-blocking SSL/TLS (via L<AnyEvent::TLS>).
1039 1102
1040=item L<AnyEvent::DNS> 1103=item L<AnyEvent::DNS>
1041 1104
1042Provides rich asynchronous DNS resolver capabilities. 1105Provides rich asynchronous DNS resolver capabilities.
1043 1106
1107=item L<AnyEvent::HTTP>, L<AnyEvent::IRC>, L<AnyEvent::XMPP>, L<AnyEvent::GPSD>, L<AnyEvent::IGS>, L<AnyEvent::FCP>
1108
1109Implement event-based interfaces to the protocols of the same name (for
1110the curious, IGS is the International Go Server and FCP is the Freenet
1111Client Protocol).
1112
1113=item L<AnyEvent::Handle::UDP>
1114
1115Here be danger!
1116
1117As Pauli would put it, "Not only is it not right, it's not even wrong!" -
1118there are so many things wrong with AnyEvent::Handle::UDP, most notably
1119its use of a stream-based API with a protocol that isn't streamable, that
1120the only way to improve it is to delete it.
1121
1122It features data corruption (but typically only under load) and general
1123confusion. On top, the author is not only clueless about UDP but also
1124fact-resistant - some gems of his understanding: "connect doesn't work
1125with UDP", "UDP packets are not IP packets", "UDP only has datagrams, not
1126packets", "I don't need to implement proper error checking as UDP doesn't
1127support error checking" and so on - he doesn't even understand what's
1128wrong with his module when it is explained to him.
1129
1044=item L<AnyEvent::HTTP> 1130=item L<AnyEvent::DBI>
1045 1131
1046A simple-to-use HTTP library that is capable of making a lot of concurrent 1132Executes L<DBI> requests asynchronously in a proxy process for you,
1047HTTP requests. 1133notifying you in an event-based way when the operation is finished.
1134
1135=item L<AnyEvent::AIO>
1136
1137Truly asynchronous (as opposed to non-blocking) I/O, should be in the
1138toolbox of every event programmer. AnyEvent::AIO transparently fuses
1139L<IO::AIO> and AnyEvent together, giving AnyEvent access to event-based
1140file I/O, and much more.
1048 1141
1049=item L<AnyEvent::HTTPD> 1142=item L<AnyEvent::HTTPD>
1050 1143
1051Provides a simple web application server framework. 1144A simple embedded webserver.
1052 1145
1053=item L<AnyEvent::FastPing> 1146=item L<AnyEvent::FastPing>
1054 1147
1055The fastest ping in the west. 1148The fastest ping in the west.
1056
1057=item L<AnyEvent::DBI>
1058
1059Executes L<DBI> requests asynchronously in a proxy process.
1060
1061=item L<AnyEvent::AIO>
1062
1063Truly asynchronous I/O, should be in the toolbox of every event
1064programmer. AnyEvent::AIO transparently fuses L<IO::AIO> and AnyEvent
1065together.
1066
1067=item L<AnyEvent::BDB>
1068
1069Truly asynchronous Berkeley DB access. AnyEvent::BDB transparently fuses
1070L<BDB> and AnyEvent together.
1071
1072=item L<AnyEvent::GPSD>
1073
1074A non-blocking interface to gpsd, a daemon delivering GPS information.
1075
1076=item L<AnyEvent::IRC>
1077
1078AnyEvent based IRC client module family (replacing the older Net::IRC3).
1079
1080=item L<AnyEvent::XMPP>
1081
1082AnyEvent based XMPP (Jabber protocol) module family (replacing the older
1083Net::XMPP2>.
1084
1085=item L<AnyEvent::IGS>
1086
1087A non-blocking interface to the Internet Go Server protocol (used by
1088L<App::IGS>).
1089
1090=item L<Net::FCP>
1091
1092AnyEvent-based implementation of the Freenet Client Protocol, birthplace
1093of AnyEvent.
1094
1095=item L<Event::ExecFlow>
1096
1097High level API for event-based execution flow control.
1098 1149
1099=item L<Coro> 1150=item L<Coro>
1100 1151
1101Has special support for AnyEvent via L<Coro::AnyEvent>. 1152Has special support for AnyEvent via L<Coro::AnyEvent>.
1102 1153
1106 1157
1107package AnyEvent; 1158package AnyEvent;
1108 1159
1109# basically a tuned-down version of common::sense 1160# basically a tuned-down version of common::sense
1110sub common_sense { 1161sub common_sense {
1111 # from common:.sense 1.0 1162 # from common:.sense 3.3
1112 ${^WARNING_BITS} = "\xfc\x3f\xf3\x00\x0f\xf3\xcf\xc0\xf3\xfc\x33\x03"; 1163 ${^WARNING_BITS} ^= ${^WARNING_BITS} ^ "\x3c\x3f\x33\x00\x0f\xf3\x0f\xc0\xf0\xfc\x33\x00";
1113 # use strict vars subs 1164 # use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl)
1114 $^H |= 0x00000600; 1165 $^H |= 0x00000600;
1115} 1166}
1116 1167
1117BEGIN { AnyEvent::common_sense } 1168BEGIN { AnyEvent::common_sense }
1118 1169
1119use Carp (); 1170use Carp ();
1120 1171
1121our $VERSION = '5.202'; 1172our $VERSION = '5.29';
1122our $MODEL; 1173our $MODEL;
1123 1174
1124our $AUTOLOAD; 1175our $AUTOLOAD;
1125our @ISA; 1176our @ISA;
1126 1177
1127our @REGISTRY; 1178our @REGISTRY;
1128 1179
1129our $WIN32;
1130
1131our $VERBOSE; 1180our $VERBOSE;
1132 1181
1133BEGIN { 1182BEGIN {
1134 eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }"; 1183 require "AnyEvent/constants.pl";
1184
1135 eval "sub TAINT(){ " . (${^TAINT}*1) . " }"; 1185 eval "sub TAINT (){" . (${^TAINT}*1) . "}";
1136 1186
1137 delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV} 1187 delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}
1138 if ${^TAINT}; 1188 if ${^TAINT};
1139 1189
1140 $VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1; 1190 $VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1;
1183our @post_detect; 1233our @post_detect;
1184 1234
1185sub post_detect(&) { 1235sub post_detect(&) {
1186 my ($cb) = @_; 1236 my ($cb) = @_;
1187 1237
1188 if ($MODEL) {
1189 $cb->();
1190
1191 undef
1192 } else {
1193 push @post_detect, $cb; 1238 push @post_detect, $cb;
1194 1239
1195 defined wantarray 1240 defined wantarray
1196 ? bless \$cb, "AnyEvent::Util::postdetect" 1241 ? bless \$cb, "AnyEvent::Util::postdetect"
1197 : () 1242 : ()
1198 }
1199} 1243}
1200 1244
1201sub AnyEvent::Util::postdetect::DESTROY { 1245sub AnyEvent::Util::postdetect::DESTROY {
1202 @post_detect = grep $_ != ${$_[0]}, @post_detect; 1246 @post_detect = grep $_ != ${$_[0]}, @post_detect;
1203} 1247}
1204 1248
1205sub detect() { 1249sub detect() {
1250 # free some memory
1251 *detect = sub () { $MODEL };
1252
1253 local $!; # for good measure
1254 local $SIG{__DIE__};
1255
1256 if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {
1257 my $model = "AnyEvent::Impl::$1";
1258 if (eval "require $model") {
1259 $MODEL = $model;
1260 warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2;
1261 } else {
1262 warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE;
1263 }
1264 }
1265
1266 # check for already loaded models
1206 unless ($MODEL) { 1267 unless ($MODEL) {
1207 local $SIG{__DIE__}; 1268 for (@REGISTRY, @models) {
1208 1269 my ($package, $model) = @$_;
1209 if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) { 1270 if (${"$package\::VERSION"} > 0) {
1210 my $model = "AnyEvent::Impl::$1";
1211 if (eval "require $model") { 1271 if (eval "require $model") {
1212 $MODEL = $model; 1272 $MODEL = $model;
1213 warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2; 1273 warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2;
1214 } else { 1274 last;
1215 warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE; 1275 }
1216 } 1276 }
1217 } 1277 }
1218 1278
1219 # check for already loaded models
1220 unless ($MODEL) { 1279 unless ($MODEL) {
1280 # try to autoload a model
1221 for (@REGISTRY, @models) { 1281 for (@REGISTRY, @models) {
1222 my ($package, $model) = @$_; 1282 my ($package, $model, $autoload) = @$_;
1283 if (
1284 $autoload
1285 and eval "require $package"
1223 if (${"$package\::VERSION"} > 0) { 1286 and ${"$package\::VERSION"} > 0
1224 if (eval "require $model") { 1287 and eval "require $model"
1288 ) {
1225 $MODEL = $model; 1289 $MODEL = $model;
1226 warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2; 1290 warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2;
1227 last; 1291 last;
1228 }
1229 } 1292 }
1230 } 1293 }
1231 1294
1232 unless ($MODEL) {
1233 # try to autoload a model
1234 for (@REGISTRY, @models) {
1235 my ($package, $model, $autoload) = @$_;
1236 if (
1237 $autoload
1238 and eval "require $package"
1239 and ${"$package\::VERSION"} > 0
1240 and eval "require $model"
1241 ) {
1242 $MODEL = $model;
1243 warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2;
1244 last;
1245 }
1246 }
1247
1248 $MODEL 1295 $MODEL
1249 or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.\n"; 1296 or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.\n";
1250 }
1251 } 1297 }
1252
1253 push @{"$MODEL\::ISA"}, "AnyEvent::Base";
1254
1255 unshift @ISA, $MODEL;
1256
1257 require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT};
1258
1259 (shift @post_detect)->() while @post_detect;
1260 } 1298 }
1299
1300 @models = (); # free probe data
1301
1302 push @{"$MODEL\::ISA"}, "AnyEvent::Base";
1303 unshift @ISA, $MODEL;
1304
1305 # now nuke some methods that are overriden by the backend.
1306 # SUPER is not allowed.
1307 for (qw(time signal child idle)) {
1308 undef &{"AnyEvent::Base::$_"}
1309 if defined &{"$MODEL\::$_"};
1310 }
1311
1312 require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT};
1313
1314 (shift @post_detect)->() while @post_detect;
1315
1316 *post_detect = sub(&) {
1317 shift->();
1318
1319 undef
1320 };
1261 1321
1262 $MODEL 1322 $MODEL
1263} 1323}
1264 1324
1265sub AUTOLOAD { 1325sub AUTOLOAD {
1266 (my $func = $AUTOLOAD) =~ s/.*://; 1326 (my $func = $AUTOLOAD) =~ s/.*://;
1267 1327
1268 $method{$func} 1328 $method{$func}
1269 or Carp::croak "$func: not a valid method for AnyEvent objects"; 1329 or Carp::croak "$func: not a valid AnyEvent class method";
1270 1330
1271 detect unless $MODEL; 1331 detect;
1272 1332
1273 my $class = shift; 1333 my $class = shift;
1274 $class->$func (@_); 1334 $class->$func (@_);
1275} 1335}
1276 1336
1293 1353
1294=head1 SIMPLIFIED AE API 1354=head1 SIMPLIFIED AE API
1295 1355
1296Starting with version 5.0, AnyEvent officially supports a second, much 1356Starting with version 5.0, AnyEvent officially supports a second, much
1297simpler, API that is designed to reduce the calling, typing and memory 1357simpler, API that is designed to reduce the calling, typing and memory
1298overhead. 1358overhead by using function call syntax and a fixed number of parameters.
1299 1359
1300See the L<AE> manpage for details. 1360See the L<AE> manpage for details.
1301 1361
1302=cut 1362=cut
1303 1363
1304package AE; 1364package AE;
1305 1365
1306our $VERSION = $AnyEvent::VERSION; 1366our $VERSION = $AnyEvent::VERSION;
1367
1368# fall back to the main API by default - backends and AnyEvent::Base
1369# implementations can overwrite these.
1307 1370
1308sub io($$$) { 1371sub io($$$) {
1309 AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2]) 1372 AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])
1310} 1373}
1311 1374
1343 1406
1344package AnyEvent::Base; 1407package AnyEvent::Base;
1345 1408
1346# default implementations for many methods 1409# default implementations for many methods
1347 1410
1348sub _time() { 1411sub time {
1412 eval q{ # poor man's autoloading {}
1349 # probe for availability of Time::HiRes 1413 # probe for availability of Time::HiRes
1350 if (eval "use Time::HiRes (); Time::HiRes::time (); 1") { 1414 if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
1351 warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8; 1415 warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8;
1352 *_time = \&Time::HiRes::time; 1416 *AE::time = \&Time::HiRes::time;
1353 # if (eval "use POSIX (); (POSIX::times())... 1417 # if (eval "use POSIX (); (POSIX::times())...
1354 } else { 1418 } else {
1355 warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE; 1419 warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE;
1356 *_time = sub { time }; # epic fail 1420 *AE::time = sub (){ time }; # epic fail
1421 }
1422
1423 *time = sub { AE::time }; # different prototypes
1357 } 1424 };
1425 die if $@;
1358 1426
1359 &_time 1427 &time
1360} 1428}
1361 1429
1362sub time { _time } 1430*now = \&time;
1363sub now { _time } 1431
1364sub now_update { } 1432sub now_update { }
1365 1433
1366# default implementation for ->condvar 1434# default implementation for ->condvar
1367 1435
1368sub condvar { 1436sub condvar {
1437 eval q{ # poor man's autoloading {}
1438 *condvar = sub {
1369 bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar" 1439 bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"
1440 };
1441
1442 *AE::cv = sub (;&) {
1443 bless { @_ ? (_ae_cb => shift) : () }, "AnyEvent::CondVar"
1444 };
1445 };
1446 die if $@;
1447
1448 &condvar
1370} 1449}
1371 1450
1372# default implementation for ->signal 1451# default implementation for ->signal
1373 1452
1374our $HAVE_ASYNC_INTERRUPT; 1453our $HAVE_ASYNC_INTERRUPT;
1383 1462
1384our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO); 1463our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);
1385our (%SIG_ASY, %SIG_ASY_W); 1464our (%SIG_ASY, %SIG_ASY_W);
1386our ($SIG_COUNT, $SIG_TW); 1465our ($SIG_COUNT, $SIG_TW);
1387 1466
1388sub _signal_exec {
1389 $HAVE_ASYNC_INTERRUPT
1390 ? $SIGPIPE_R->drain
1391 : sysread $SIGPIPE_R, (my $dummy), 9;
1392
1393 while (%SIG_EV) {
1394 for (keys %SIG_EV) {
1395 delete $SIG_EV{$_};
1396 $_->() for values %{ $SIG_CB{$_} || {} };
1397 }
1398 }
1399}
1400
1401# install a dummy wakeup watcher to reduce signal catching latency 1467# install a dummy wakeup watcher to reduce signal catching latency
1468# used by Impls
1402sub _sig_add() { 1469sub _sig_add() {
1403 unless ($SIG_COUNT++) { 1470 unless ($SIG_COUNT++) {
1404 # try to align timer on a full-second boundary, if possible 1471 # try to align timer on a full-second boundary, if possible
1405 my $NOW = AE::now; 1472 my $NOW = AE::now;
1406 1473
1416 undef $SIG_TW 1483 undef $SIG_TW
1417 unless --$SIG_COUNT; 1484 unless --$SIG_COUNT;
1418} 1485}
1419 1486
1420our $_sig_name_init; $_sig_name_init = sub { 1487our $_sig_name_init; $_sig_name_init = sub {
1421 eval q{ # poor man's autoloading 1488 eval q{ # poor man's autoloading {}
1422 undef $_sig_name_init; 1489 undef $_sig_name_init;
1423 1490
1424 if (_have_async_interrupt) { 1491 if (_have_async_interrupt) {
1425 *sig2num = \&Async::Interrupt::sig2num; 1492 *sig2num = \&Async::Interrupt::sig2num;
1426 *sig2name = \&Async::Interrupt::sig2name; 1493 *sig2name = \&Async::Interrupt::sig2name;
1458 $SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec; 1525 $SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;
1459 1526
1460 } else { 1527 } else {
1461 warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8; 1528 warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;
1462 1529
1463 require Fcntl;
1464
1465 if (AnyEvent::WIN32) { 1530 if (AnyEvent::WIN32) {
1466 require AnyEvent::Util; 1531 require AnyEvent::Util;
1467 1532
1468 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe (); 1533 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
1469 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R; 1534 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R;
1470 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case 1535 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case
1471 } else { 1536 } else {
1472 pipe $SIGPIPE_R, $SIGPIPE_W; 1537 pipe $SIGPIPE_R, $SIGPIPE_W;
1473 fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R; 1538 fcntl $SIGPIPE_R, AnyEvent::F_SETFL, AnyEvent::O_NONBLOCK if $SIGPIPE_R;
1474 fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case 1539 fcntl $SIGPIPE_W, AnyEvent::F_SETFL, AnyEvent::O_NONBLOCK if $SIGPIPE_W; # just in case
1475 1540
1476 # not strictly required, as $^F is normally 2, but let's make sure... 1541 # not strictly required, as $^F is normally 2, but let's make sure...
1477 fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; 1542 fcntl $SIGPIPE_R, AnyEvent::F_SETFD, AnyEvent::FD_CLOEXEC;
1478 fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; 1543 fcntl $SIGPIPE_W, AnyEvent::F_SETFD, AnyEvent::FD_CLOEXEC;
1479 } 1544 }
1480 1545
1481 $SIGPIPE_R 1546 $SIGPIPE_R
1482 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n"; 1547 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1483 1548
1484 $SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec; 1549 $SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec;
1485 } 1550 }
1486 1551
1487 *signal = sub { 1552 *signal = $HAVE_ASYNC_INTERRUPT
1553 ? sub {
1488 my (undef, %arg) = @_; 1554 my (undef, %arg) = @_;
1489 1555
1490 my $signal = uc $arg{signal}
1491 or Carp::croak "required option 'signal' is missing";
1492
1493 if ($HAVE_ASYNC_INTERRUPT) {
1494 # async::interrupt 1556 # async::interrupt
1495
1496 $signal = sig2num $signal; 1557 my $signal = sig2num $arg{signal};
1497 $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; 1558 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1498 1559
1499 $SIG_ASY{$signal} ||= new Async::Interrupt 1560 $SIG_ASY{$signal} ||= new Async::Interrupt
1500 cb => sub { undef $SIG_EV{$signal} }, 1561 cb => sub { undef $SIG_EV{$signal} },
1501 signal => $signal, 1562 signal => $signal,
1502 pipe => [$SIGPIPE_R->filenos], 1563 pipe => [$SIGPIPE_R->filenos],
1503 pipe_autodrain => 0, 1564 pipe_autodrain => 0,
1504 ; 1565 ;
1505 1566
1506 } else { 1567 bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1568 }
1569 : sub {
1570 my (undef, %arg) = @_;
1571
1507 # pure perl 1572 # pure perl
1508
1509 # AE::Util has been loaded in signal
1510 $signal = sig2name $signal; 1573 my $signal = sig2name $arg{signal};
1511 $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; 1574 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1512 1575
1513 $SIG{$signal} ||= sub { 1576 $SIG{$signal} ||= sub {
1514 local $!; 1577 local $!;
1515 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV; 1578 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
1516 undef $SIG_EV{$signal}; 1579 undef $SIG_EV{$signal};
1517 }; 1580 };
1518 1581
1519 # can't do signal processing without introducing races in pure perl, 1582 # can't do signal processing without introducing races in pure perl,
1520 # so limit the signal latency. 1583 # so limit the signal latency.
1521 _sig_add; 1584 _sig_add;
1522 }
1523 1585
1524 bless [$signal, $arg{cb}], "AnyEvent::Base::signal" 1586 bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1587 }
1525 }; 1588 ;
1526 1589
1527 *AnyEvent::Base::signal::DESTROY = sub { 1590 *AnyEvent::Base::signal::DESTROY = sub {
1528 my ($signal, $cb) = @{$_[0]}; 1591 my ($signal, $cb) = @{$_[0]};
1529 1592
1530 _sig_del; 1593 _sig_del;
1537 # print weird messages, or just unconditionally exit 1600 # print weird messages, or just unconditionally exit
1538 # instead of getting the default action. 1601 # instead of getting the default action.
1539 undef $SIG{$signal} 1602 undef $SIG{$signal}
1540 unless keys %{ $SIG_CB{$signal} }; 1603 unless keys %{ $SIG_CB{$signal} };
1541 }; 1604 };
1605
1606 *_signal_exec = sub {
1607 $HAVE_ASYNC_INTERRUPT
1608 ? $SIGPIPE_R->drain
1609 : sysread $SIGPIPE_R, (my $dummy), 9;
1610
1611 while (%SIG_EV) {
1612 for (keys %SIG_EV) {
1613 delete $SIG_EV{$_};
1614 $_->() for values %{ $SIG_CB{$_} || {} };
1615 }
1616 }
1617 };
1542 }; 1618 };
1543 die if $@; 1619 die if $@;
1620
1544 &signal 1621 &signal
1545} 1622}
1546 1623
1547# default implementation for ->child 1624# default implementation for ->child
1548 1625
1549our %PID_CB; 1626our %PID_CB;
1550our $CHLD_W; 1627our $CHLD_W;
1551our $CHLD_DELAY_W; 1628our $CHLD_DELAY_W;
1552our $WNOHANG; 1629our $WNOHANG;
1553 1630
1631# used by many Impl's
1554sub _emit_childstatus($$) { 1632sub _emit_childstatus($$) {
1555 my (undef, $rpid, $rstatus) = @_; 1633 my (undef, $rpid, $rstatus) = @_;
1556 1634
1557 $_->($rpid, $rstatus) 1635 $_->($rpid, $rstatus)
1558 for values %{ $PID_CB{$rpid} || {} }, 1636 for values %{ $PID_CB{$rpid} || {} },
1559 values %{ $PID_CB{0} || {} }; 1637 values %{ $PID_CB{0} || {} };
1560} 1638}
1561 1639
1562sub _sigchld {
1563 my $pid;
1564
1565 AnyEvent->_emit_childstatus ($pid, $?)
1566 while ($pid = waitpid -1, $WNOHANG) > 0;
1567}
1568
1569sub child { 1640sub child {
1641 eval q{ # poor man's autoloading {}
1642 *_sigchld = sub {
1643 my $pid;
1644
1645 AnyEvent->_emit_childstatus ($pid, $?)
1646 while ($pid = waitpid -1, $WNOHANG) > 0;
1647 };
1648
1649 *child = sub {
1570 my (undef, %arg) = @_; 1650 my (undef, %arg) = @_;
1571 1651
1572 defined (my $pid = $arg{pid} + 0) 1652 defined (my $pid = $arg{pid} + 0)
1573 or Carp::croak "required option 'pid' is missing"; 1653 or Carp::croak "required option 'pid' is missing";
1574 1654
1575 $PID_CB{$pid}{$arg{cb}} = $arg{cb}; 1655 $PID_CB{$pid}{$arg{cb}} = $arg{cb};
1576 1656
1577 # WNOHANG is almost cetrainly 1 everywhere 1657 # WNOHANG is almost cetrainly 1 everywhere
1578 $WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/ 1658 $WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/
1579 ? 1 1659 ? 1
1580 : eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1; 1660 : eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1;
1581 1661
1582 unless ($CHLD_W) { 1662 unless ($CHLD_W) {
1583 $CHLD_W = AE::signal CHLD => \&_sigchld; 1663 $CHLD_W = AE::signal CHLD => \&_sigchld;
1584 # child could be a zombie already, so make at least one round 1664 # child could be a zombie already, so make at least one round
1585 &_sigchld; 1665 &_sigchld;
1586 } 1666 }
1587 1667
1588 bless [$pid, $arg{cb}], "AnyEvent::Base::child" 1668 bless [$pid, $arg{cb}], "AnyEvent::Base::child"
1589} 1669 };
1590 1670
1591sub AnyEvent::Base::child::DESTROY { 1671 *AnyEvent::Base::child::DESTROY = sub {
1592 my ($pid, $cb) = @{$_[0]}; 1672 my ($pid, $cb) = @{$_[0]};
1593 1673
1594 delete $PID_CB{$pid}{$cb}; 1674 delete $PID_CB{$pid}{$cb};
1595 delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} }; 1675 delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };
1596 1676
1597 undef $CHLD_W unless keys %PID_CB; 1677 undef $CHLD_W unless keys %PID_CB;
1678 };
1679 };
1680 die if $@;
1681
1682 &child
1598} 1683}
1599 1684
1600# idle emulation is done by simply using a timer, regardless 1685# idle emulation is done by simply using a timer, regardless
1601# of whether the process is idle or not, and not letting 1686# of whether the process is idle or not, and not letting
1602# the callback use more than 50% of the time. 1687# the callback use more than 50% of the time.
1603sub idle { 1688sub idle {
1689 eval q{ # poor man's autoloading {}
1690 *idle = sub {
1604 my (undef, %arg) = @_; 1691 my (undef, %arg) = @_;
1605 1692
1606 my ($cb, $w, $rcb) = $arg{cb}; 1693 my ($cb, $w, $rcb) = $arg{cb};
1607 1694
1608 $rcb = sub { 1695 $rcb = sub {
1609 if ($cb) { 1696 if ($cb) {
1610 $w = _time; 1697 $w = _time;
1611 &$cb; 1698 &$cb;
1612 $w = _time - $w; 1699 $w = _time - $w;
1613 1700
1614 # never use more then 50% of the time for the idle watcher, 1701 # never use more then 50% of the time for the idle watcher,
1615 # within some limits 1702 # within some limits
1616 $w = 0.0001 if $w < 0.0001; 1703 $w = 0.0001 if $w < 0.0001;
1617 $w = 5 if $w > 5; 1704 $w = 5 if $w > 5;
1618 1705
1619 $w = AE::timer $w, 0, $rcb; 1706 $w = AE::timer $w, 0, $rcb;
1620 } else { 1707 } else {
1621 # clean up... 1708 # clean up...
1622 undef $w; 1709 undef $w;
1623 undef $rcb; 1710 undef $rcb;
1711 }
1712 };
1713
1714 $w = AE::timer 0.05, 0, $rcb;
1715
1716 bless \\$cb, "AnyEvent::Base::idle"
1624 } 1717 };
1718
1719 *AnyEvent::Base::idle::DESTROY = sub {
1720 undef $${$_[0]};
1721 };
1625 }; 1722 };
1723 die if $@;
1626 1724
1627 $w = AE::timer 0.05, 0, $rcb; 1725 &idle
1628
1629 bless \\$cb, "AnyEvent::Base::idle"
1630}
1631
1632sub AnyEvent::Base::idle::DESTROY {
1633 undef $${$_[0]};
1634} 1726}
1635 1727
1636package AnyEvent::CondVar; 1728package AnyEvent::CondVar;
1637 1729
1638our @ISA = AnyEvent::CondVar::Base::; 1730our @ISA = AnyEvent::CondVar::Base::;
1731
1732# only to be used for subclassing
1733sub new {
1734 my $class = shift;
1735 bless AnyEvent->condvar (@_), $class
1736}
1639 1737
1640package AnyEvent::CondVar::Base; 1738package AnyEvent::CondVar::Base;
1641 1739
1642#use overload 1740#use overload
1643# '&{}' => sub { my $self = shift; sub { $self->send (@_) } }, 1741# '&{}' => sub { my $self = shift; sub { $self->send (@_) } },
1765check the arguments passed to most method calls. If it finds any problems, 1863check the arguments passed to most method calls. If it finds any problems,
1766it will croak. 1864it will croak.
1767 1865
1768In other words, enables "strict" mode. 1866In other words, enables "strict" mode.
1769 1867
1770Unlike C<use strict> (or it's modern cousin, C<< use L<common::sense> 1868Unlike C<use strict> (or its modern cousin, C<< use L<common::sense>
1771>>, it is definitely recommended to keep it off in production. Keeping 1869>>, it is definitely recommended to keep it off in production. Keeping
1772C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs 1870C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs
1773can be very useful, however. 1871can be very useful, however.
1774 1872
1775=item C<PERL_ANYEVENT_MODEL> 1873=item C<PERL_ANYEVENT_MODEL>
1997 2095
1998The actual code goes further and collects all errors (C<die>s, exceptions) 2096The actual code goes further and collects all errors (C<die>s, exceptions)
1999that occurred during request processing. The C<result> method detects 2097that occurred during request processing. The C<result> method detects
2000whether an exception as thrown (it is stored inside the $txn object) 2098whether an exception as thrown (it is stored inside the $txn object)
2001and just throws the exception, which means connection errors and other 2099and just throws the exception, which means connection errors and other
2002problems get reported tot he code that tries to use the result, not in a 2100problems get reported to the code that tries to use the result, not in a
2003random callback. 2101random callback.
2004 2102
2005All of this enables the following usage styles: 2103All of this enables the following usage styles:
2006 2104
20071. Blocking: 21051. Blocking:
2421 unless defined $SIG{PIPE}; 2519 unless defined $SIG{PIPE};
2422 2520
2423=head1 RECOMMENDED/OPTIONAL MODULES 2521=head1 RECOMMENDED/OPTIONAL MODULES
2424 2522
2425One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and 2523One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and
2426it's built-in modules) are required to use it. 2524its built-in modules) are required to use it.
2427 2525
2428That does not mean that AnyEvent won't take advantage of some additional 2526That does not mean that AnyEvent won't take advantage of some additional
2429modules if they are installed. 2527modules if they are installed.
2430 2528
2431This section epxlains which additional modules will be used, and how they 2529This section explains which additional modules will be used, and how they
2432affect AnyEvent's operetion. 2530affect AnyEvent's operation.
2433 2531
2434=over 4 2532=over 4
2435 2533
2436=item L<Async::Interrupt> 2534=item L<Async::Interrupt>
2437 2535
2442catch the signals) with some delay (default is 10 seconds, look for 2540catch the signals) with some delay (default is 10 seconds, look for
2443C<$AnyEvent::MAX_SIGNAL_LATENCY>). 2541C<$AnyEvent::MAX_SIGNAL_LATENCY>).
2444 2542
2445If this module is available, then it will be used to implement signal 2543If this module is available, then it will be used to implement signal
2446catching, which means that signals will not be delayed, and the event loop 2544catching, which means that signals will not be delayed, and the event loop
2447will not be interrupted regularly, which is more efficient (And good for 2545will not be interrupted regularly, which is more efficient (and good for
2448battery life on laptops). 2546battery life on laptops).
2449 2547
2450This affects not just the pure-perl event loop, but also other event loops 2548This affects not just the pure-perl event loop, but also other event loops
2451that have no signal handling on their own (e.g. Glib, Tk, Qt). 2549that have no signal handling on their own (e.g. Glib, Tk, Qt).
2452 2550
2464automatic timer adjustments even when no monotonic clock is available, 2562automatic timer adjustments even when no monotonic clock is available,
2465can take avdantage of advanced kernel interfaces such as C<epoll> and 2563can take avdantage of advanced kernel interfaces such as C<epoll> and
2466C<kqueue>, and is the fastest backend I<by far>. You can even embed 2564C<kqueue>, and is the fastest backend I<by far>. You can even embed
2467L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>). 2565L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>).
2468 2566
2567If you only use backends that rely on another event loop (e.g. C<Tk>),
2568then this module will do nothing for you.
2569
2469=item L<Guard> 2570=item L<Guard>
2470 2571
2471The guard module, when used, will be used to implement 2572The guard module, when used, will be used to implement
2472C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a 2573C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a
2473lot less memory), but otherwise doesn't affect guard operation much. It is 2574lot less memory), but otherwise doesn't affect guard operation much. It is
2474purely used for performance. 2575purely used for performance.
2475 2576
2476=item L<JSON> and L<JSON::XS> 2577=item L<JSON> and L<JSON::XS>
2477 2578
2478One of these modules is required when you want to read or write JSON data 2579One of these modules is required when you want to read or write JSON data
2479via L<AnyEvent::Handle>. It is also written in pure-perl, but can take 2580via L<AnyEvent::Handle>. L<JSON> is also written in pure-perl, but can take
2480advantage of the ultra-high-speed L<JSON::XS> module when it is installed. 2581advantage of the ultra-high-speed L<JSON::XS> module when it is installed.
2481
2482In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is
2483installed.
2484 2582
2485=item L<Net::SSLeay> 2583=item L<Net::SSLeay>
2486 2584
2487Implementing TLS/SSL in Perl is certainly interesting, but not very 2585Implementing TLS/SSL in Perl is certainly interesting, but not very
2488worthwhile: If this module is installed, then L<AnyEvent::Handle> (with 2586worthwhile: If this module is installed, then L<AnyEvent::Handle> (with
2489the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL. 2587the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL.
2490 2588
2491=item L<Time::HiRes> 2589=item L<Time::HiRes>
2492 2590
2493This module is part of perl since release 5.008. It will be used when the 2591This module is part of perl since release 5.008. It will be used when the
2494chosen event library does not come with a timing source on it's own. The 2592chosen event library does not come with a timing source of its own. The
2495pure-perl event loop (L<AnyEvent::Impl::Perl>) will additionally use it to 2593pure-perl event loop (L<AnyEvent::Impl::Perl>) will additionally use it to
2496try to use a monotonic clock for timing stability. 2594try to use a monotonic clock for timing stability.
2497 2595
2498=back 2596=back
2499 2597
2500 2598
2501=head1 FORK 2599=head1 FORK
2502 2600
2503Most event libraries are not fork-safe. The ones who are usually are 2601Most event libraries are not fork-safe. The ones who are usually are
2504because they rely on inefficient but fork-safe C<select> or C<poll> 2602because they rely on inefficient but fork-safe C<select> or C<poll> calls
2505calls. Only L<EV> is fully fork-aware. 2603- higher performance APIs such as BSD's kqueue or the dreaded Linux epoll
2604are usually badly thought-out hacks that are incompatible with fork in
2605one way or another. Only L<EV> is fully fork-aware and ensures that you
2606continue event-processing in both parent and child (or both, if you know
2607what you are doing).
2608
2609This means that, in general, you cannot fork and do event processing in
2610the child if the event library was initialised before the fork (which
2611usually happens when the first AnyEvent watcher is created, or the library
2612is loaded).
2506 2613
2507If you have to fork, you must either do so I<before> creating your first 2614If you have to fork, you must either do so I<before> creating your first
2508watcher OR you must not use AnyEvent at all in the child OR you must do 2615watcher OR you must not use AnyEvent at all in the child OR you must do
2509something completely out of the scope of AnyEvent. 2616something completely out of the scope of AnyEvent.
2617
2618The problem of doing event processing in the parent I<and> the child
2619is much more complicated: even for backends that I<are> fork-aware or
2620fork-safe, their behaviour is not usually what you want: fork clones all
2621watchers, that means all timers, I/O watchers etc. are active in both
2622parent and child, which is almost never what you want. USing C<exec>
2623to start worker children from some kind of manage rprocess is usually
2624preferred, because it is much easier and cleaner, at the expense of having
2625to have another binary.
2510 2626
2511 2627
2512=head1 SECURITY CONSIDERATIONS 2628=head1 SECURITY CONSIDERATIONS
2513 2629
2514AnyEvent can be forced to load any event model via 2630AnyEvent can be forced to load any event model via
2544pronounced). 2660pronounced).
2545 2661
2546 2662
2547=head1 SEE ALSO 2663=head1 SEE ALSO
2548 2664
2665Tutorial/Introduction: L<AnyEvent::Intro>.
2666
2667FAQ: L<AnyEvent::FAQ>.
2668
2549Utility functions: L<AnyEvent::Util>. 2669Utility functions: L<AnyEvent::Util>.
2550 2670
2551Event modules: L<EV>, L<EV::Glib>, L<Glib::EV>, L<Event>, L<Glib::Event>, 2671Event modules: L<EV>, L<EV::Glib>, L<Glib::EV>, L<Event>, L<Glib::Event>,
2552L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. 2672L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.
2553 2673
2559Non-blocking file handles, sockets, TCP clients and 2679Non-blocking file handles, sockets, TCP clients and
2560servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>. 2680servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.
2561 2681
2562Asynchronous DNS: L<AnyEvent::DNS>. 2682Asynchronous DNS: L<AnyEvent::DNS>.
2563 2683
2564Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, 2684Thread support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>.
2565L<Coro::Event>,
2566 2685
2567Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::XMPP>, 2686Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::IRC>,
2568L<AnyEvent::HTTP>. 2687L<AnyEvent::HTTP>.
2569 2688
2570 2689
2571=head1 AUTHOR 2690=head1 AUTHOR
2572 2691

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