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

Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.290 by root, Tue Sep 1 18:27:46 2009 UTC vs.
Revision 1.350 by root, Tue Aug 2 20:02:44 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
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
828 AnyEvent::Impl::Glib based on Glib, slow but very stable. 876 AnyEvent::Impl::Glib based on Glib, slow but very stable.
829 AnyEvent::Impl::Tk based on Tk, very broken. 877 AnyEvent::Impl::Tk based on Tk, very broken.
830 AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. 878 AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
831 AnyEvent::Impl::POE based on POE, very slow, some limitations. 879 AnyEvent::Impl::POE based on POE, very slow, some limitations.
832 AnyEvent::Impl::Irssi used when running within irssi. 880 AnyEvent::Impl::Irssi used when running within irssi.
881 AnyEvent::Impl::IOAsync based on IO::Async.
882 AnyEvent::Impl::Cocoa based on Cocoa::EventLoop.
883 AnyEvent::Impl::FLTK based on FLTK.
833 884
834=item Backends with special needs. 885=item Backends with special needs.
835 886
836Qt requires the Qt::Application to be instantiated first, but will 887Qt requires the Qt::Application to be instantiated first, but will
837otherwise be picked up automatically. As long as the main program 888otherwise be picked up automatically. As long as the main program
838instantiates the application before any AnyEvent watchers are created, 889instantiates the application before any AnyEvent watchers are created,
839everything should just work. 890everything should just work.
840 891
841 AnyEvent::Impl::Qt based on Qt. 892 AnyEvent::Impl::Qt based on Qt.
842 893
843Support for IO::Async can only be partial, as it is too broken and
844architecturally limited to even support the AnyEvent API. It also
845is 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
847L<AnyEvent::Impl::Async> for the gory details.
848
849 AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed.
850
851=item Event loops that are indirectly supported via other backends. 894=item Event loops that are indirectly supported via other backends.
852 895
853Some event loops can be supported via other modules: 896Some event loops can be supported via other modules:
854 897
855There is no direct support for WxWidgets (L<Wx>) or L<Prima>. 898There is no direct support for WxWidgets (L<Wx>) or L<Prima>.
880Contains C<undef> until the first watcher is being created, before the 923Contains C<undef> until the first watcher is being created, before the
881backend has been autodetected. 924backend has been autodetected.
882 925
883Afterwards it contains the event model that is being used, which is the 926Afterwards it contains the event model that is being used, which is the
884name of the Perl class implementing the model. This class is usually one 927name of the Perl class implementing the model. This class is usually one
885of the C<AnyEvent::Impl:xxx> modules, but can be any other class in the 928of the C<AnyEvent::Impl::xxx> modules, but can be any other class in the
886case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it 929case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it
887will be C<urxvt::anyevent>). 930will be C<urxvt::anyevent>).
888 931
889=item AnyEvent::detect 932=item AnyEvent::detect
890 933
891Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model 934Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model
892if necessary. You should only call this function right before you would 935if necessary. You should only call this function right before you would
893have created an AnyEvent watcher anyway, that is, as late as possible at 936have created an AnyEvent watcher anyway, that is, as late as possible at
894runtime, and not e.g. while initialising of your module. 937runtime, and not e.g. during initialisation of your module.
895 938
896If you need to do some initialisation before AnyEvent watchers are 939If you need to do some initialisation before AnyEvent watchers are
897created, use C<post_detect>. 940created, use C<post_detect>.
898 941
899=item $guard = AnyEvent::post_detect { BLOCK } 942=item $guard = AnyEvent::post_detect { BLOCK }
900 943
901Arranges for the code block to be executed as soon as the event model is 944Arranges for the code block to be executed as soon as the event model is
902autodetected (or immediately if this has already happened). 945autodetected (or immediately if that has already happened).
903 946
904The block will be executed I<after> the actual backend has been detected 947The block will be executed I<after> the actual backend has been detected
905(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been 948(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been
906created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do 949created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do
907other initialisations - see the sources of L<AnyEvent::Strict> or 950other initialisations - see the sources of L<AnyEvent::Strict> or
916that automatically removes the callback again when it is destroyed (or 959that automatically removes the callback again when it is destroyed (or
917C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for 960C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for
918a case where this is useful. 961a case where this is useful.
919 962
920Example: Create a watcher for the IO::AIO module and store it in 963Example: Create a watcher for the IO::AIO module and store it in
921C<$WATCHER>. Only do so after the event loop is initialised, though. 964C<$WATCHER>, but do so only do so after the event loop is initialised.
922 965
923 our WATCHER; 966 our WATCHER;
924 967
925 my $guard = AnyEvent::post_detect { 968 my $guard = AnyEvent::post_detect {
926 $WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb); 969 $WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb);
934 $WATCHER ||= $guard; 977 $WATCHER ||= $guard;
935 978
936=item @AnyEvent::post_detect 979=item @AnyEvent::post_detect
937 980
938If there are any code references in this array (you can C<push> to it 981If there are any code references in this array (you can C<push> to it
939before or after loading AnyEvent), then they will called directly after 982before or after loading AnyEvent), then they will be called directly
940the event loop has been chosen. 983after the event loop has been chosen.
941 984
942You should check C<$AnyEvent::MODEL> before adding to this array, though: 985You 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 986if it is defined then the event loop has already been detected, and the
944array will be ignored. 987array will be ignored.
945 988
946Best use C<AnyEvent::post_detect { BLOCK }> when your application allows 989Best use C<AnyEvent::post_detect { BLOCK }> when your application allows
947it,as it takes care of these details. 990it, as it takes care of these details.
948 991
949This variable is mainly useful for modules that can do something useful 992This 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 993when 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 994not need to even load it by default. This array provides the means to hook
952into AnyEvent passively, without loading it. 995into AnyEvent passively, without loading it.
953 996
997Example: To load Coro::AnyEvent whenever Coro and AnyEvent are used
998together, you could put this into Coro (this is the actual code used by
999Coro to accomplish this):
1000
1001 if (defined $AnyEvent::MODEL) {
1002 # AnyEvent already initialised, so load Coro::AnyEvent
1003 require Coro::AnyEvent;
1004 } else {
1005 # AnyEvent not yet initialised, so make sure to load Coro::AnyEvent
1006 # as soon as it is
1007 push @AnyEvent::post_detect, sub { require Coro::AnyEvent };
1008 }
1009
954=back 1010=back
955 1011
956=head1 WHAT TO DO IN A MODULE 1012=head1 WHAT TO DO IN A MODULE
957 1013
958As a module author, you should C<use AnyEvent> and call AnyEvent methods 1014As 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 1024because it will stall the whole program, and the whole point of using
969events is to stay interactive. 1025events is to stay interactive.
970 1026
971It is fine, however, to call C<< ->recv >> when the user of your module 1027It is fine, however, to call C<< ->recv >> when the user of your module
972requests it (i.e. if you create a http request object ad have a method 1028requests it (i.e. if you create a http request object ad have a method
973called C<results> that returns the results, it should call C<< ->recv >> 1029called C<results> that returns the results, it may call C<< ->recv >>
974freely, as the user of your module knows what she is doing. always). 1030freely, as the user of your module knows what she is doing. Always).
975 1031
976=head1 WHAT TO DO IN THE MAIN PROGRAM 1032=head1 WHAT TO DO IN THE MAIN PROGRAM
977 1033
978There will always be a single main program - the only place that should 1034There will always be a single main program - the only place that should
979dictate which event model to use. 1035dictate which event model to use.
980 1036
981If it doesn't care, it can just "use AnyEvent" and use it itself, or not 1037If the program is not event-based, it need not do anything special, even
982do anything special (it does not need to be event-based) and let AnyEvent 1038when it depends on a module that uses an AnyEvent. If the program itself
983decide which implementation to chose if some module relies on it. 1039uses AnyEvent, but does not care which event loop is used, all it needs
1040to do is C<use AnyEvent>. In either case, AnyEvent will choose the best
1041available loop implementation.
984 1042
985If the main program relies on a specific event model - for example, in 1043If the main program relies on a specific event model - for example, in
986Gtk2 programs you have to rely on the Glib module - you should load the 1044Gtk2 programs you have to rely on the Glib module - you should load the
987event module before loading AnyEvent or any module that uses it: generally 1045event module before loading AnyEvent or any module that uses it: generally
988speaking, you should load it as early as possible. The reason is that 1046speaking, you should load it as early as possible. The reason is that
989modules might create watchers when they are loaded, and AnyEvent will 1047modules 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 1048decide 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. 1049might choose the wrong one unless you load the correct one yourself.
992 1050
993You can chose to use a pure-perl implementation by loading the 1051You can chose to use a pure-perl implementation by loading the
994C<AnyEvent::Impl::Perl> module, which gives you similar behaviour 1052C<AnyEvent::Impl::Perl> module, which gives you similar behaviour
995everywhere, but letting AnyEvent chose the model is generally better. 1053everywhere, but letting AnyEvent chose the model is generally better.
996 1054
1014=head1 OTHER MODULES 1072=head1 OTHER MODULES
1015 1073
1016The following is a non-exhaustive list of additional modules that use 1074The following is a non-exhaustive list of additional modules that use
1017AnyEvent as a client and can therefore be mixed easily with other AnyEvent 1075AnyEvent as a client and can therefore be mixed easily with other AnyEvent
1018modules and other event loops in the same program. Some of the modules 1076modules and other event loops in the same program. Some of the modules
1019come with AnyEvent, most are available via CPAN. 1077come as part of AnyEvent, the others are available via CPAN.
1020 1078
1021=over 4 1079=over 4
1022 1080
1023=item L<AnyEvent::Util> 1081=item L<AnyEvent::Util>
1024 1082
1025Contains various utility functions that replace often-used but blocking 1083Contains various utility functions that replace often-used blocking
1026functions such as C<inet_aton> by event-/callback-based versions. 1084functions such as C<inet_aton> with event/callback-based versions.
1027 1085
1028=item L<AnyEvent::Socket> 1086=item L<AnyEvent::Socket>
1029 1087
1030Provides various utility functions for (internet protocol) sockets, 1088Provides various utility functions for (internet protocol) sockets,
1031addresses and name resolution. Also functions to create non-blocking tcp 1089addresses and name resolution. Also functions to create non-blocking tcp
1033 1091
1034=item L<AnyEvent::Handle> 1092=item L<AnyEvent::Handle>
1035 1093
1036Provide read and write buffers, manages watchers for reads and writes, 1094Provide read and write buffers, manages watchers for reads and writes,
1037supports raw and formatted I/O, I/O queued and fully transparent and 1095supports raw and formatted I/O, I/O queued and fully transparent and
1038non-blocking SSL/TLS (via L<AnyEvent::TLS>. 1096non-blocking SSL/TLS (via L<AnyEvent::TLS>).
1039 1097
1040=item L<AnyEvent::DNS> 1098=item L<AnyEvent::DNS>
1041 1099
1042Provides rich asynchronous DNS resolver capabilities. 1100Provides rich asynchronous DNS resolver capabilities.
1043 1101
1102=item L<AnyEvent::HTTP>, L<AnyEvent::IRC>, L<AnyEvent::XMPP>, L<AnyEvent::GPSD>, L<AnyEvent::IGS>, L<AnyEvent::FCP>
1103
1104Implement event-based interfaces to the protocols of the same name (for
1105the curious, IGS is the International Go Server and FCP is the Freenet
1106Client Protocol).
1107
1108=item L<AnyEvent::Handle::UDP>
1109
1110Here be danger!
1111
1112As Pauli would put it, "Not only is it not right, it's not even wrong!" -
1113there are so many things wrong with AnyEvent::Handle::UDP, most notably
1114its use of a stream-based API with a protocol that isn't streamable, that
1115the only way to improve it is to delete it.
1116
1117It features data corruption (but typically only under load) and general
1118confusion. On top, the author is not only clueless about UDP but also
1119fact-resistant - some gems of his understanding: "connect doesn't work
1120with UDP", "UDP packets are not IP packets", "UDP only has datagrams, not
1121packets", "I don't need to implement proper error checking as UDP doesn't
1122support error checking" and so on - he doesn't even understand what's
1123wrong with his module when it is explained to him.
1124
1044=item L<AnyEvent::HTTP> 1125=item L<AnyEvent::DBI>
1045 1126
1046A simple-to-use HTTP library that is capable of making a lot of concurrent 1127Executes L<DBI> requests asynchronously in a proxy process for you,
1047HTTP requests. 1128notifying you in an event-based way when the operation is finished.
1129
1130=item L<AnyEvent::AIO>
1131
1132Truly asynchronous (as opposed to non-blocking) I/O, should be in the
1133toolbox of every event programmer. AnyEvent::AIO transparently fuses
1134L<IO::AIO> and AnyEvent together, giving AnyEvent access to event-based
1135file I/O, and much more.
1048 1136
1049=item L<AnyEvent::HTTPD> 1137=item L<AnyEvent::HTTPD>
1050 1138
1051Provides a simple web application server framework. 1139A simple embedded webserver.
1052 1140
1053=item L<AnyEvent::FastPing> 1141=item L<AnyEvent::FastPing>
1054 1142
1055The fastest ping in the west. 1143The 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 1144
1099=item L<Coro> 1145=item L<Coro>
1100 1146
1101Has special support for AnyEvent via L<Coro::AnyEvent>. 1147Has special support for AnyEvent via L<Coro::AnyEvent>.
1102 1148
1106 1152
1107package AnyEvent; 1153package AnyEvent;
1108 1154
1109# basically a tuned-down version of common::sense 1155# basically a tuned-down version of common::sense
1110sub common_sense { 1156sub common_sense {
1111 # from common:.sense 1.0 1157 # from common:.sense 3.4
1112 ${^WARNING_BITS} = "\xfc\x3f\xf3\x00\x0f\xf3\xcf\xc0\xf3\xfc\x33\x03"; 1158 ${^WARNING_BITS} ^= ${^WARNING_BITS} ^ "\x3c\x3f\x33\x00\x0f\xf0\x0f\xc0\xf0\xfc\x33\x00";
1113 # use strict vars subs 1159 # use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl)
1114 $^H |= 0x00000600; 1160 $^H |= 0x00000600;
1115} 1161}
1116 1162
1117BEGIN { AnyEvent::common_sense } 1163BEGIN { AnyEvent::common_sense }
1118 1164
1119use Carp (); 1165use Carp ();
1120 1166
1121our $VERSION = '5.12'; 1167our $VERSION = '5.34';
1122our $MODEL; 1168our $MODEL;
1123 1169
1124our $AUTOLOAD; 1170our $AUTOLOAD;
1125our @ISA; 1171our @ISA;
1126 1172
1127our @REGISTRY; 1173our @REGISTRY;
1128 1174
1129our $WIN32;
1130
1131our $VERBOSE; 1175our $VERBOSE;
1132 1176
1133BEGIN { 1177BEGIN {
1134 eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }"; 1178 require "AnyEvent/constants.pl";
1179
1135 eval "sub TAINT(){ " . (${^TAINT}*1) . " }"; 1180 eval "sub TAINT (){" . (${^TAINT}*1) . "}";
1136 1181
1137 delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV} 1182 delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}
1138 if ${^TAINT}; 1183 if ${^TAINT};
1139 1184
1140 $VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1; 1185 $VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1;
1165 [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles 1210 [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
1166 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program 1211 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program
1167 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza 1212 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
1168 [Wx:: => AnyEvent::Impl::POE::], 1213 [Wx:: => AnyEvent::Impl::POE::],
1169 [Prima:: => AnyEvent::Impl::POE::], 1214 [Prima:: => AnyEvent::Impl::POE::],
1170 # IO::Async is just too broken - we would need workarounds for its
1171 # byzantine signal and broken child handling, among others.
1172 # IO::Async is rather hard to detect, as it doesn't have any
1173 # obvious default class.
1174 [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program
1175 [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program 1215 [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::],
1176 [IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program 1216 [Cocoa::EventLoop:: => AnyEvent::Impl::Cocoa::],
1177 [AnyEvent::Impl::IOAsync:: => AnyEvent::Impl::IOAsync::], # requires special main program 1217 [FLTK:: => AnyEvent::Impl::FLTK::],
1178); 1218);
1179 1219
1180our %method = map +($_ => 1), 1220our %method = map +($_ => 1),
1181 qw(io timer time now now_update signal child idle condvar one_event DESTROY); 1221 qw(io timer time now now_update signal child idle condvar DESTROY);
1182 1222
1183our @post_detect; 1223our @post_detect;
1184 1224
1185sub post_detect(&) { 1225sub post_detect(&) {
1186 my ($cb) = @_; 1226 my ($cb) = @_;
1187 1227
1188 if ($MODEL) {
1189 $cb->();
1190
1191 undef
1192 } else {
1193 push @post_detect, $cb; 1228 push @post_detect, $cb;
1194 1229
1195 defined wantarray 1230 defined wantarray
1196 ? bless \$cb, "AnyEvent::Util::postdetect" 1231 ? bless \$cb, "AnyEvent::Util::postdetect"
1197 : () 1232 : ()
1198 }
1199} 1233}
1200 1234
1201sub AnyEvent::Util::postdetect::DESTROY { 1235sub AnyEvent::Util::postdetect::DESTROY {
1202 @post_detect = grep $_ != ${$_[0]}, @post_detect; 1236 @post_detect = grep $_ != ${$_[0]}, @post_detect;
1203} 1237}
1204 1238
1205sub detect() { 1239sub detect() {
1240 # free some memory
1241 *detect = sub () { $MODEL };
1242
1243 local $!; # for good measure
1244 local $SIG{__DIE__};
1245
1246 if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {
1247 my $model = "AnyEvent::Impl::$1";
1248 if (eval "require $model") {
1249 $MODEL = $model;
1250 warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2;
1251 } else {
1252 warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE;
1253 }
1254 }
1255
1256 # check for already loaded models
1206 unless ($MODEL) { 1257 unless ($MODEL) {
1207 local $SIG{__DIE__}; 1258 for (@REGISTRY, @models) {
1208 1259 my ($package, $model) = @$_;
1209 if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) { 1260 if (${"$package\::VERSION"} > 0) {
1210 my $model = "AnyEvent::Impl::$1";
1211 if (eval "require $model") { 1261 if (eval "require $model") {
1212 $MODEL = $model; 1262 $MODEL = $model;
1213 warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2; 1263 warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2;
1214 } else { 1264 last;
1215 warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE; 1265 }
1216 } 1266 }
1217 } 1267 }
1218 1268
1219 # check for already loaded models
1220 unless ($MODEL) { 1269 unless ($MODEL) {
1270 # try to autoload a model
1221 for (@REGISTRY, @models) { 1271 for (@REGISTRY, @models) {
1222 my ($package, $model) = @$_; 1272 my ($package, $model, $autoload) = @$_;
1273 if (
1274 $autoload
1275 and eval "require $package"
1223 if (${"$package\::VERSION"} > 0) { 1276 and ${"$package\::VERSION"} > 0
1224 if (eval "require $model") { 1277 and eval "require $model"
1278 ) {
1225 $MODEL = $model; 1279 $MODEL = $model;
1226 warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2; 1280 warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2;
1227 last; 1281 last;
1228 }
1229 } 1282 }
1230 } 1283 }
1231 1284
1232 unless ($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 1285 $MODEL
1249 or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.\n"; 1286 or die "AnyEvent: backend autodetection failed - did you properly install AnyEvent?\n";
1250 }
1251 } 1287 }
1252
1253 push @{"$MODEL\::ISA"}, "AnyEvent::Base";
1254
1255 unshift @ISA, $MODEL;
1256
1257 require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT};
1258
1259 (shift @post_detect)->() while @post_detect;
1260 } 1288 }
1289
1290 @models = (); # free probe data
1291
1292 push @{"$MODEL\::ISA"}, "AnyEvent::Base";
1293 unshift @ISA, $MODEL;
1294
1295 # now nuke some methods that are overridden by the backend.
1296 # SUPER is not allowed.
1297 for (qw(time signal child idle)) {
1298 undef &{"AnyEvent::Base::$_"}
1299 if defined &{"$MODEL\::$_"};
1300 }
1301
1302 if ($ENV{PERL_ANYEVENT_STRICT}) {
1303 eval { require AnyEvent::Strict };
1304 warn "AnyEvent: cannot load AnyEvent::Strict: $@"
1305 if $@ && $VERBOSE;
1306 }
1307
1308 (shift @post_detect)->() while @post_detect;
1309
1310 *post_detect = sub(&) {
1311 shift->();
1312
1313 undef
1314 };
1261 1315
1262 $MODEL 1316 $MODEL
1263} 1317}
1264 1318
1265sub AUTOLOAD { 1319sub AUTOLOAD {
1266 (my $func = $AUTOLOAD) =~ s/.*://; 1320 (my $func = $AUTOLOAD) =~ s/.*://;
1267 1321
1268 $method{$func} 1322 $method{$func}
1269 or Carp::croak "$func: not a valid method for AnyEvent objects"; 1323 or Carp::croak "$func: not a valid AnyEvent class method";
1270 1324
1271 detect unless $MODEL; 1325 detect;
1272 1326
1273 my $class = shift; 1327 my $class = shift;
1274 $class->$func (@_); 1328 $class->$func (@_);
1275} 1329}
1276 1330
1293 1347
1294=head1 SIMPLIFIED AE API 1348=head1 SIMPLIFIED AE API
1295 1349
1296Starting with version 5.0, AnyEvent officially supports a second, much 1350Starting with version 5.0, AnyEvent officially supports a second, much
1297simpler, API that is designed to reduce the calling, typing and memory 1351simpler, API that is designed to reduce the calling, typing and memory
1298overhead. 1352overhead by using function call syntax and a fixed number of parameters.
1299 1353
1300See the L<AE> manpage for details. 1354See the L<AE> manpage for details.
1301 1355
1302=cut 1356=cut
1303 1357
1304package AE; 1358package AE;
1305 1359
1306our $VERSION = $AnyEvent::VERSION; 1360our $VERSION = $AnyEvent::VERSION;
1361
1362# fall back to the main API by default - backends and AnyEvent::Base
1363# implementations can overwrite these.
1307 1364
1308sub io($$$) { 1365sub io($$$) {
1309 AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2]) 1366 AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])
1310} 1367}
1311 1368
1343 1400
1344package AnyEvent::Base; 1401package AnyEvent::Base;
1345 1402
1346# default implementations for many methods 1403# default implementations for many methods
1347 1404
1348sub _time() { 1405sub time {
1406 eval q{ # poor man's autoloading {}
1349 # probe for availability of Time::HiRes 1407 # probe for availability of Time::HiRes
1350 if (eval "use Time::HiRes (); Time::HiRes::time (); 1") { 1408 if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
1351 warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8; 1409 warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8;
1352 *_time = \&Time::HiRes::time; 1410 *AE::time = \&Time::HiRes::time;
1353 # if (eval "use POSIX (); (POSIX::times())... 1411 # if (eval "use POSIX (); (POSIX::times())...
1354 } else { 1412 } else {
1355 warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE; 1413 warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE;
1356 *_time = sub { time }; # epic fail 1414 *AE::time = sub (){ time }; # epic fail
1415 }
1416
1417 *time = sub { AE::time }; # different prototypes
1357 } 1418 };
1419 die if $@;
1358 1420
1359 &_time 1421 &time
1360} 1422}
1361 1423
1362sub time { _time } 1424*now = \&time;
1363sub now { _time } 1425
1364sub now_update { } 1426sub now_update { }
1365 1427
1366# default implementation for ->condvar 1428# default implementation for ->condvar
1367 1429
1368sub condvar { 1430sub condvar {
1431 eval q{ # poor man's autoloading {}
1432 *condvar = sub {
1369 bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar" 1433 bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"
1434 };
1435
1436 *AE::cv = sub (;&) {
1437 bless { @_ ? (_ae_cb => shift) : () }, "AnyEvent::CondVar"
1438 };
1439 };
1440 die if $@;
1441
1442 &condvar
1370} 1443}
1371 1444
1372# default implementation for ->signal 1445# default implementation for ->signal
1373 1446
1374our $HAVE_ASYNC_INTERRUPT; 1447our $HAVE_ASYNC_INTERRUPT;
1383 1456
1384our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO); 1457our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);
1385our (%SIG_ASY, %SIG_ASY_W); 1458our (%SIG_ASY, %SIG_ASY_W);
1386our ($SIG_COUNT, $SIG_TW); 1459our ($SIG_COUNT, $SIG_TW);
1387 1460
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 1461# install a dummy wakeup watcher to reduce signal catching latency
1462# used by Impls
1402sub _sig_add() { 1463sub _sig_add() {
1403 unless ($SIG_COUNT++) { 1464 unless ($SIG_COUNT++) {
1404 # try to align timer on a full-second boundary, if possible 1465 # try to align timer on a full-second boundary, if possible
1405 my $NOW = AE::now; 1466 my $NOW = AE::now;
1406 1467
1416 undef $SIG_TW 1477 undef $SIG_TW
1417 unless --$SIG_COUNT; 1478 unless --$SIG_COUNT;
1418} 1479}
1419 1480
1420our $_sig_name_init; $_sig_name_init = sub { 1481our $_sig_name_init; $_sig_name_init = sub {
1421 eval q{ # poor man's autoloading 1482 eval q{ # poor man's autoloading {}
1422 undef $_sig_name_init; 1483 undef $_sig_name_init;
1423 1484
1424 if (_have_async_interrupt) { 1485 if (_have_async_interrupt) {
1425 *sig2num = \&Async::Interrupt::sig2num; 1486 *sig2num = \&Async::Interrupt::sig2num;
1426 *sig2name = \&Async::Interrupt::sig2name; 1487 *sig2name = \&Async::Interrupt::sig2name;
1458 $SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec; 1519 $SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;
1459 1520
1460 } else { 1521 } else {
1461 warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8; 1522 warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;
1462 1523
1463 require Fcntl;
1464
1465 if (AnyEvent::WIN32) { 1524 if (AnyEvent::WIN32) {
1466 require AnyEvent::Util; 1525 require AnyEvent::Util;
1467 1526
1468 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe (); 1527 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
1469 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R; 1528 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R;
1470 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case 1529 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case
1471 } else { 1530 } else {
1472 pipe $SIGPIPE_R, $SIGPIPE_W; 1531 pipe $SIGPIPE_R, $SIGPIPE_W;
1473 fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R; 1532 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 1533 fcntl $SIGPIPE_W, AnyEvent::F_SETFL, AnyEvent::O_NONBLOCK if $SIGPIPE_W; # just in case
1475 1534
1476 # not strictly required, as $^F is normally 2, but let's make sure... 1535 # not strictly required, as $^F is normally 2, but let's make sure...
1477 fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; 1536 fcntl $SIGPIPE_R, AnyEvent::F_SETFD, AnyEvent::FD_CLOEXEC;
1478 fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; 1537 fcntl $SIGPIPE_W, AnyEvent::F_SETFD, AnyEvent::FD_CLOEXEC;
1479 } 1538 }
1480 1539
1481 $SIGPIPE_R 1540 $SIGPIPE_R
1482 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n"; 1541 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1483 1542
1484 $SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec; 1543 $SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec;
1485 } 1544 }
1486 1545
1487 *signal = sub { 1546 *signal = $HAVE_ASYNC_INTERRUPT
1547 ? sub {
1488 my (undef, %arg) = @_; 1548 my (undef, %arg) = @_;
1489 1549
1490 my $signal = uc $arg{signal}
1491 or Carp::croak "required option 'signal' is missing";
1492
1493 if ($HAVE_ASYNC_INTERRUPT) {
1494 # async::interrupt 1550 # async::interrupt
1495
1496 $signal = sig2num $signal; 1551 my $signal = sig2num $arg{signal};
1497 $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; 1552 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1498 1553
1499 $SIG_ASY{$signal} ||= new Async::Interrupt 1554 $SIG_ASY{$signal} ||= new Async::Interrupt
1500 cb => sub { undef $SIG_EV{$signal} }, 1555 cb => sub { undef $SIG_EV{$signal} },
1501 signal => $signal, 1556 signal => $signal,
1502 pipe => [$SIGPIPE_R->filenos], 1557 pipe => [$SIGPIPE_R->filenos],
1503 pipe_autodrain => 0, 1558 pipe_autodrain => 0,
1504 ; 1559 ;
1505 1560
1506 } else { 1561 bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1562 }
1563 : sub {
1564 my (undef, %arg) = @_;
1565
1507 # pure perl 1566 # pure perl
1508
1509 # AE::Util has been loaded in signal
1510 $signal = sig2name $signal; 1567 my $signal = sig2name $arg{signal};
1511 $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; 1568 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1512 1569
1513 $SIG{$signal} ||= sub { 1570 $SIG{$signal} ||= sub {
1514 local $!; 1571 local $!;
1515 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV; 1572 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
1516 undef $SIG_EV{$signal}; 1573 undef $SIG_EV{$signal};
1517 }; 1574 };
1518 1575
1519 # can't do signal processing without introducing races in pure perl, 1576 # can't do signal processing without introducing races in pure perl,
1520 # so limit the signal latency. 1577 # so limit the signal latency.
1521 _sig_add; 1578 _sig_add;
1522 }
1523 1579
1524 bless [$signal, $arg{cb}], "AnyEvent::Base::signal" 1580 bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1581 }
1525 }; 1582 ;
1526 1583
1527 *AnyEvent::Base::signal::DESTROY = sub { 1584 *AnyEvent::Base::signal::DESTROY = sub {
1528 my ($signal, $cb) = @{$_[0]}; 1585 my ($signal, $cb) = @{$_[0]};
1529 1586
1530 _sig_del; 1587 _sig_del;
1537 # print weird messages, or just unconditionally exit 1594 # print weird messages, or just unconditionally exit
1538 # instead of getting the default action. 1595 # instead of getting the default action.
1539 undef $SIG{$signal} 1596 undef $SIG{$signal}
1540 unless keys %{ $SIG_CB{$signal} }; 1597 unless keys %{ $SIG_CB{$signal} };
1541 }; 1598 };
1599
1600 *_signal_exec = sub {
1601 $HAVE_ASYNC_INTERRUPT
1602 ? $SIGPIPE_R->drain
1603 : sysread $SIGPIPE_R, (my $dummy), 9;
1604
1605 while (%SIG_EV) {
1606 for (keys %SIG_EV) {
1607 delete $SIG_EV{$_};
1608 $_->() for values %{ $SIG_CB{$_} || {} };
1609 }
1610 }
1611 };
1542 }; 1612 };
1543 die if $@; 1613 die if $@;
1614
1544 &signal 1615 &signal
1545} 1616}
1546 1617
1547# default implementation for ->child 1618# default implementation for ->child
1548 1619
1549our %PID_CB; 1620our %PID_CB;
1550our $CHLD_W; 1621our $CHLD_W;
1551our $CHLD_DELAY_W; 1622our $CHLD_DELAY_W;
1552our $WNOHANG;
1553 1623
1624# used by many Impl's
1554sub _emit_childstatus($$) { 1625sub _emit_childstatus($$) {
1555 my (undef, $rpid, $rstatus) = @_; 1626 my (undef, $rpid, $rstatus) = @_;
1556 1627
1557 $_->($rpid, $rstatus) 1628 $_->($rpid, $rstatus)
1558 for values %{ $PID_CB{$rpid} || {} }, 1629 for values %{ $PID_CB{$rpid} || {} },
1559 values %{ $PID_CB{0} || {} }; 1630 values %{ $PID_CB{0} || {} };
1560} 1631}
1561 1632
1562sub _sigchld {
1563 my $pid;
1564
1565 AnyEvent->_emit_childstatus ($pid, $?)
1566 while ($pid = waitpid -1, $WNOHANG) > 0;
1567}
1568
1569sub child { 1633sub child {
1634 eval q{ # poor man's autoloading {}
1635 *_sigchld = sub {
1636 my $pid;
1637
1638 AnyEvent->_emit_childstatus ($pid, $?)
1639 while ($pid = waitpid -1, WNOHANG) > 0;
1640 };
1641
1642 *child = sub {
1570 my (undef, %arg) = @_; 1643 my (undef, %arg) = @_;
1571 1644
1572 defined (my $pid = $arg{pid} + 0) 1645 defined (my $pid = $arg{pid} + 0)
1573 or Carp::croak "required option 'pid' is missing"; 1646 or Carp::croak "required option 'pid' is missing";
1574 1647
1575 $PID_CB{$pid}{$arg{cb}} = $arg{cb}; 1648 $PID_CB{$pid}{$arg{cb}} = $arg{cb};
1576 1649
1577 # WNOHANG is almost cetrainly 1 everywhere
1578 $WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/
1579 ? 1
1580 : eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1;
1581
1582 unless ($CHLD_W) { 1650 unless ($CHLD_W) {
1583 $CHLD_W = AE::signal CHLD => \&_sigchld; 1651 $CHLD_W = AE::signal CHLD => \&_sigchld;
1584 # child could be a zombie already, so make at least one round 1652 # child could be a zombie already, so make at least one round
1585 &_sigchld; 1653 &_sigchld;
1586 } 1654 }
1587 1655
1588 bless [$pid, $arg{cb}], "AnyEvent::Base::child" 1656 bless [$pid, $arg{cb}], "AnyEvent::Base::child"
1589} 1657 };
1590 1658
1591sub AnyEvent::Base::child::DESTROY { 1659 *AnyEvent::Base::child::DESTROY = sub {
1592 my ($pid, $cb) = @{$_[0]}; 1660 my ($pid, $cb) = @{$_[0]};
1593 1661
1594 delete $PID_CB{$pid}{$cb}; 1662 delete $PID_CB{$pid}{$cb};
1595 delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} }; 1663 delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };
1596 1664
1597 undef $CHLD_W unless keys %PID_CB; 1665 undef $CHLD_W unless keys %PID_CB;
1666 };
1667 };
1668 die if $@;
1669
1670 &child
1598} 1671}
1599 1672
1600# idle emulation is done by simply using a timer, regardless 1673# idle emulation is done by simply using a timer, regardless
1601# of whether the process is idle or not, and not letting 1674# of whether the process is idle or not, and not letting
1602# the callback use more than 50% of the time. 1675# the callback use more than 50% of the time.
1603sub idle { 1676sub idle {
1677 eval q{ # poor man's autoloading {}
1678 *idle = sub {
1604 my (undef, %arg) = @_; 1679 my (undef, %arg) = @_;
1605 1680
1606 my ($cb, $w, $rcb) = $arg{cb}; 1681 my ($cb, $w, $rcb) = $arg{cb};
1607 1682
1608 $rcb = sub { 1683 $rcb = sub {
1609 if ($cb) { 1684 if ($cb) {
1610 $w = _time; 1685 $w = _time;
1611 &$cb; 1686 &$cb;
1612 $w = _time - $w; 1687 $w = _time - $w;
1613 1688
1614 # never use more then 50% of the time for the idle watcher, 1689 # never use more then 50% of the time for the idle watcher,
1615 # within some limits 1690 # within some limits
1616 $w = 0.0001 if $w < 0.0001; 1691 $w = 0.0001 if $w < 0.0001;
1617 $w = 5 if $w > 5; 1692 $w = 5 if $w > 5;
1618 1693
1619 $w = AE::timer $w, 0, $rcb; 1694 $w = AE::timer $w, 0, $rcb;
1620 } else { 1695 } else {
1621 # clean up... 1696 # clean up...
1622 undef $w; 1697 undef $w;
1623 undef $rcb; 1698 undef $rcb;
1699 }
1700 };
1701
1702 $w = AE::timer 0.05, 0, $rcb;
1703
1704 bless \\$cb, "AnyEvent::Base::idle"
1624 } 1705 };
1706
1707 *AnyEvent::Base::idle::DESTROY = sub {
1708 undef $${$_[0]};
1709 };
1625 }; 1710 };
1711 die if $@;
1626 1712
1627 $w = AE::timer 0.05, 0, $rcb; 1713 &idle
1628
1629 bless \\$cb, "AnyEvent::Base::idle"
1630}
1631
1632sub AnyEvent::Base::idle::DESTROY {
1633 undef $${$_[0]};
1634} 1714}
1635 1715
1636package AnyEvent::CondVar; 1716package AnyEvent::CondVar;
1637 1717
1638our @ISA = AnyEvent::CondVar::Base::; 1718our @ISA = AnyEvent::CondVar::Base::;
1719
1720# only to be used for subclassing
1721sub new {
1722 my $class = shift;
1723 bless AnyEvent->condvar (@_), $class
1724}
1639 1725
1640package AnyEvent::CondVar::Base; 1726package AnyEvent::CondVar::Base;
1641 1727
1642#use overload 1728#use overload
1643# '&{}' => sub { my $self = shift; sub { $self->send (@_) } }, 1729# '&{}' => sub { my $self = shift; sub { $self->send (@_) } },
1653 1739
1654sub _send { 1740sub _send {
1655 # nop 1741 # nop
1656} 1742}
1657 1743
1744sub _wait {
1745 Carp::croak "$AnyEvent::MODEL does not support blocking waits. Caught";
1746}
1747
1658sub send { 1748sub send {
1659 my $cv = shift; 1749 my $cv = shift;
1660 $cv->{_ae_sent} = [@_]; 1750 $cv->{_ae_sent} = [@_];
1661 (delete $cv->{_ae_cb})->($cv) if $cv->{_ae_cb}; 1751 (delete $cv->{_ae_cb})->($cv) if $cv->{_ae_cb};
1662 $cv->_send; 1752 $cv->_send;
1669 1759
1670sub ready { 1760sub ready {
1671 $_[0]{_ae_sent} 1761 $_[0]{_ae_sent}
1672} 1762}
1673 1763
1674sub _wait {
1675 $WAITING
1676 and !$_[0]{_ae_sent}
1677 and Carp::croak "AnyEvent::CondVar: recursive blocking wait detected";
1678
1679 local $WAITING = 1;
1680 AnyEvent->one_event while !$_[0]{_ae_sent};
1681}
1682
1683sub recv { 1764sub recv {
1765 unless ($_[0]{_ae_sent}) {
1766 $WAITING
1767 and Carp::croak "AnyEvent::CondVar: recursive blocking wait detected";
1768
1769 local $WAITING = 1;
1684 $_[0]->_wait; 1770 $_[0]->_wait;
1771 }
1685 1772
1686 Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak}; 1773 $_[0]{_ae_croak}
1687 wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0] 1774 and Carp::croak $_[0]{_ae_croak};
1775
1776 wantarray
1777 ? @{ $_[0]{_ae_sent} }
1778 : $_[0]{_ae_sent}[0]
1688} 1779}
1689 1780
1690sub cb { 1781sub cb {
1691 my $cv = shift; 1782 my $cv = shift;
1692 1783
1708 &{ $_[0]{_ae_end_cb} || sub { $_[0]->send } }; 1799 &{ $_[0]{_ae_end_cb} || sub { $_[0]->send } };
1709} 1800}
1710 1801
1711# undocumented/compatibility with pre-3.4 1802# undocumented/compatibility with pre-3.4
1712*broadcast = \&send; 1803*broadcast = \&send;
1713*wait = \&_wait; 1804*wait = \&recv;
1714 1805
1715=head1 ERROR AND EXCEPTION HANDLING 1806=head1 ERROR AND EXCEPTION HANDLING
1716 1807
1717In general, AnyEvent does not do any error handling - it relies on the 1808In general, AnyEvent does not do any error handling - it relies on the
1718caller to do that if required. The L<AnyEvent::Strict> module (see also 1809caller to do that if required. The L<AnyEvent::Strict> module (see also
1765check the arguments passed to most method calls. If it finds any problems, 1856check the arguments passed to most method calls. If it finds any problems,
1766it will croak. 1857it will croak.
1767 1858
1768In other words, enables "strict" mode. 1859In other words, enables "strict" mode.
1769 1860
1770Unlike C<use strict> (or it's modern cousin, C<< use L<common::sense> 1861Unlike C<use strict> (or its modern cousin, C<< use L<common::sense>
1771>>, it is definitely recommended to keep it off in production. Keeping 1862>>, it is definitely recommended to keep it off in production. Keeping
1772C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs 1863C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs
1773can be very useful, however. 1864can be very useful, however.
1774 1865
1775=item C<PERL_ANYEVENT_MODEL> 1866=item C<PERL_ANYEVENT_MODEL>
1997 2088
1998The actual code goes further and collects all errors (C<die>s, exceptions) 2089The actual code goes further and collects all errors (C<die>s, exceptions)
1999that occurred during request processing. The C<result> method detects 2090that occurred during request processing. The C<result> method detects
2000whether an exception as thrown (it is stored inside the $txn object) 2091whether an exception as thrown (it is stored inside the $txn object)
2001and just throws the exception, which means connection errors and other 2092and 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 2093problems get reported to the code that tries to use the result, not in a
2003random callback. 2094random callback.
2004 2095
2005All of this enables the following usage styles: 2096All of this enables the following usage styles:
2006 2097
20071. Blocking: 20981. Blocking:
2421 unless defined $SIG{PIPE}; 2512 unless defined $SIG{PIPE};
2422 2513
2423=head1 RECOMMENDED/OPTIONAL MODULES 2514=head1 RECOMMENDED/OPTIONAL MODULES
2424 2515
2425One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and 2516One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and
2426it's built-in modules) are required to use it. 2517its built-in modules) are required to use it.
2427 2518
2428That does not mean that AnyEvent won't take advantage of some additional 2519That does not mean that AnyEvent won't take advantage of some additional
2429modules if they are installed. 2520modules if they are installed.
2430 2521
2431This section epxlains which additional modules will be used, and how they 2522This section explains which additional modules will be used, and how they
2432affect AnyEvent's operetion. 2523affect AnyEvent's operation.
2433 2524
2434=over 4 2525=over 4
2435 2526
2436=item L<Async::Interrupt> 2527=item L<Async::Interrupt>
2437 2528
2442catch the signals) with some delay (default is 10 seconds, look for 2533catch the signals) with some delay (default is 10 seconds, look for
2443C<$AnyEvent::MAX_SIGNAL_LATENCY>). 2534C<$AnyEvent::MAX_SIGNAL_LATENCY>).
2444 2535
2445If this module is available, then it will be used to implement signal 2536If 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 2537catching, which means that signals will not be delayed, and the event loop
2447will not be interrupted regularly, which is more efficient (And good for 2538will not be interrupted regularly, which is more efficient (and good for
2448battery life on laptops). 2539battery life on laptops).
2449 2540
2450This affects not just the pure-perl event loop, but also other event loops 2541This 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). 2542that have no signal handling on their own (e.g. Glib, Tk, Qt).
2452 2543
2464automatic timer adjustments even when no monotonic clock is available, 2555automatic timer adjustments even when no monotonic clock is available,
2465can take avdantage of advanced kernel interfaces such as C<epoll> and 2556can 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 2557C<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>). 2558L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>).
2468 2559
2560If you only use backends that rely on another event loop (e.g. C<Tk>),
2561then this module will do nothing for you.
2562
2469=item L<Guard> 2563=item L<Guard>
2470 2564
2471The guard module, when used, will be used to implement 2565The guard module, when used, will be used to implement
2472C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a 2566C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a
2473lot less memory), but otherwise doesn't affect guard operation much. It is 2567lot less memory), but otherwise doesn't affect guard operation much. It is
2474purely used for performance. 2568purely used for performance.
2475 2569
2476=item L<JSON> and L<JSON::XS> 2570=item L<JSON> and L<JSON::XS>
2477 2571
2478This module is required when you want to read or write JSON data via 2572One of these modules is required when you want to read or write JSON data
2479L<AnyEvent::Handle>. It is also written in pure-perl, but can take 2573via 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. 2574advantage 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 2575
2485=item L<Net::SSLeay> 2576=item L<Net::SSLeay>
2486 2577
2487Implementing TLS/SSL in Perl is certainly interesting, but not very 2578Implementing TLS/SSL in Perl is certainly interesting, but not very
2488worthwhile: If this module is installed, then L<AnyEvent::Handle> (with 2579worthwhile: If this module is installed, then L<AnyEvent::Handle> (with
2489the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL. 2580the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL.
2490 2581
2491=item L<Time::HiRes> 2582=item L<Time::HiRes>
2492 2583
2493This module is part of perl since release 5.008. It will be used when the 2584This 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 2585chosen 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 2586pure-perl event loop (L<AnyEvent::Impl::Perl>) will additionally use it to
2496try to use a monotonic clock for timing stability. 2587try to use a monotonic clock for timing stability.
2497 2588
2498=back 2589=back
2499 2590
2500 2591
2501=head1 FORK 2592=head1 FORK
2502 2593
2503Most event libraries are not fork-safe. The ones who are usually are 2594Most 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> 2595because they rely on inefficient but fork-safe C<select> or C<poll> calls
2505calls. Only L<EV> is fully fork-aware. 2596- higher performance APIs such as BSD's kqueue or the dreaded Linux epoll
2597are usually badly thought-out hacks that are incompatible with fork in
2598one way or another. Only L<EV> is fully fork-aware and ensures that you
2599continue event-processing in both parent and child (or both, if you know
2600what you are doing).
2601
2602This means that, in general, you cannot fork and do event processing in
2603the child if the event library was initialised before the fork (which
2604usually happens when the first AnyEvent watcher is created, or the library
2605is loaded).
2506 2606
2507If you have to fork, you must either do so I<before> creating your first 2607If 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 2608watcher OR you must not use AnyEvent at all in the child OR you must do
2509something completely out of the scope of AnyEvent. 2609something completely out of the scope of AnyEvent.
2610
2611The problem of doing event processing in the parent I<and> the child
2612is much more complicated: even for backends that I<are> fork-aware or
2613fork-safe, their behaviour is not usually what you want: fork clones all
2614watchers, that means all timers, I/O watchers etc. are active in both
2615parent and child, which is almost never what you want. USing C<exec>
2616to start worker children from some kind of manage rprocess is usually
2617preferred, because it is much easier and cleaner, at the expense of having
2618to have another binary.
2510 2619
2511 2620
2512=head1 SECURITY CONSIDERATIONS 2621=head1 SECURITY CONSIDERATIONS
2513 2622
2514AnyEvent can be forced to load any event model via 2623AnyEvent can be forced to load any event model via
2544pronounced). 2653pronounced).
2545 2654
2546 2655
2547=head1 SEE ALSO 2656=head1 SEE ALSO
2548 2657
2658Tutorial/Introduction: L<AnyEvent::Intro>.
2659
2660FAQ: L<AnyEvent::FAQ>.
2661
2549Utility functions: L<AnyEvent::Util>. 2662Utility functions: L<AnyEvent::Util>.
2550 2663
2551Event modules: L<EV>, L<EV::Glib>, L<Glib::EV>, L<Event>, L<Glib::Event>, 2664Event 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>. 2665L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.
2553 2666
2559Non-blocking file handles, sockets, TCP clients and 2672Non-blocking file handles, sockets, TCP clients and
2560servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>. 2673servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.
2561 2674
2562Asynchronous DNS: L<AnyEvent::DNS>. 2675Asynchronous DNS: L<AnyEvent::DNS>.
2563 2676
2564Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, 2677Thread support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>.
2565L<Coro::Event>,
2566 2678
2567Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::XMPP>, 2679Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::IRC>,
2568L<AnyEvent::HTTP>. 2680L<AnyEvent::HTTP>.
2569 2681
2570 2682
2571=head1 AUTHOR 2683=head1 AUTHOR
2572 2684

Diff Legend

Removed lines
+ Added lines
< Changed lines
> Changed lines