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1=head1 NAME 1=head1 NAME
2 2
3AnyEvent - the DBI of event loop programming 3AnyEvent - the DBI of event loop programming
4 4
5EV, Event, Glib, Tk, Perl, Event::Lib, Irssi, rxvt-unicode, IO::Async, Qt 5EV, Event, Glib, Tk, Perl, Event::Lib, Irssi, rxvt-unicode, IO::Async, Qt,
6and POE are various supported event loops/environments. 6FLTK and POE are various supported event loops/environments.
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::Loop>,
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::Loop> 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 C<AnyEvent::Loop>. Like
144C<AnyEvent::Impl::Perl>. Like other event modules you can load it 148other event modules you can load it explicitly and enjoy the high
145explicitly and enjoy the high availability of that event loop :) 149availability of that event loop :)
146 150
147=head1 WATCHERS 151=head1 WATCHERS
148 152
149AnyEvent has the central concept of a I<watcher>, which is an object that 153AnyEvent has the central concept of a I<watcher>, which is an object that
150stores relevant data for each kind of event you are waiting for, such as 154stores relevant data for each kind of event you are waiting for, such as
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
352difference between C<< AnyEvent->time >> and C<< AnyEvent->now >> into 356difference between C<< AnyEvent->time >> and C<< AnyEvent->now >> into
353account. 357account.
354 358
355=item AnyEvent->now_update 359=item AnyEvent->now_update
356 360
357Some event loops (such as L<EV> or L<AnyEvent::Impl::Perl>) cache 361Some event loops (such as L<EV> or L<AnyEvent::Loop>) cache the current
358the current time for each loop iteration (see the discussion of L<< 362time for each loop iteration (see the discussion of L<< AnyEvent->now >>,
359AnyEvent->now >>, above). 363above).
360 364
361When a callback runs for a long time (or when the process sleeps), then 365When a callback runs for a long time (or when the process sleeps), then
362this "current" time will differ substantially from the real time, which 366this "current" time will differ substantially from the real time, which
363might affect timers and time-outs. 367might affect timers and time-outs.
364 368
411not restart syscalls (that includes L<Async::Interrupt> and AnyEvent's 415not restart syscalls (that includes L<Async::Interrupt> and AnyEvent's
412pure perl implementation). 416pure perl implementation).
413 417
414=head3 Safe/Unsafe Signals 418=head3 Safe/Unsafe Signals
415 419
416Perl signals can be either "safe" (synchronous to opcode handling) or 420Perl signals can be either "safe" (synchronous to opcode handling)
417"unsafe" (asynchronous) - the former might get delayed indefinitely, the 421or "unsafe" (asynchronous) - the former might delay signal delivery
418latter might corrupt your memory. 422indefinitely, the latter might corrupt your memory.
419 423
420AnyEvent signal handlers are, in addition, synchronous to the event loop, 424AnyEvent signal handlers are, in addition, synchronous to the event loop,
421i.e. they will not interrupt your running perl program but will only be 425i.e. they will not interrupt your running perl program but will only be
422called as part of the normal event handling (just like timer, I/O etc. 426called as part of the normal event handling (just like timer, I/O etc.
423callbacks, too). 427callbacks, too).
424 428
425=head3 Signal Races, Delays and Workarounds 429=head3 Signal Races, Delays and Workarounds
426 430
427Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching 431Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support
428callbacks to signals in a generic way, which is a pity, as you cannot 432attaching callbacks to signals in a generic way, which is a pity,
429do race-free signal handling in perl, requiring C libraries for 433as you cannot do race-free signal handling in perl, requiring
430this. AnyEvent will try to do it's best, which means in some cases, 434C libraries for this. AnyEvent will try to do its best, which
431signals will be delayed. The maximum time a signal might be delayed is 435means in some cases, signals will be delayed. The maximum time
432specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This 436a signal might be delayed is 10 seconds by default, but can
433variable can be changed only before the first signal watcher is created, 437be overriden via C<$ENV{PERL_ANYEVENT_MAX_SIGNAL_LATENCY}> or
434and should be left alone otherwise. This variable determines how often 438C<$AnyEvent::MAX_SIGNAL_LATENCY> - see the Ö<ENVIRONMENT VARIABLES>
435AnyEvent polls for signals (in case a wake-up was missed). Higher values 439section for details.
436will cause fewer spurious wake-ups, which is better for power and CPU
437saving.
438 440
439All these problems can be avoided by installing the optional 441All these problems can be avoided by installing the optional
440L<Async::Interrupt> module, which works with most event loops. It will not 442L<Async::Interrupt> module, which works with most event loops. It will not
441work with inherently broken event loops such as L<Event> or L<Event::Lib> 443work with inherently broken event loops such as L<Event> or L<Event::Lib>
442(and not with L<POE> currently, as POE does it's own workaround with 444(and not with L<POE> currently). For those, you just have to suffer the
443one-second latency). For those, you just have to suffer the delays. 445delays.
444 446
445=head2 CHILD PROCESS WATCHERS 447=head2 CHILD PROCESS WATCHERS
446 448
447 $w = AnyEvent->child (pid => <process id>, cb => <callback>); 449 $w = AnyEvent->child (pid => <process id>, cb => <callback>);
448 450
449You can also watch on a child process exit and catch its exit status. 451You can also watch for a child process exit and catch its exit status.
450 452
451The child process is specified by the C<pid> argument (one some backends, 453The child process is specified by the C<pid> argument (on some backends,
452using C<0> watches for any child process exit, on others this will 454using C<0> watches for any child process exit, on others this will
453croak). The watcher will be triggered only when the child process has 455croak). The watcher will be triggered only when the child process has
454finished and an exit status is available, not on any trace events 456finished and an exit status is available, not on any trace events
455(stopped/continued). 457(stopped/continued).
456 458
478thing in an AnyEvent program, you I<have> to create at least one 480thing in an AnyEvent program, you I<have> to create at least one
479watcher before you C<fork> the child (alternatively, you can call 481watcher before you C<fork> the child (alternatively, you can call
480C<AnyEvent::detect>). 482C<AnyEvent::detect>).
481 483
482As most event loops do not support waiting for child events, they will be 484As most event loops do not support waiting for child events, they will be
483emulated by AnyEvent in most cases, in which the latency and race problems 485emulated by AnyEvent in most cases, in which case the latency and race
484mentioned in the description of signal watchers apply. 486problems mentioned in the description of signal watchers apply.
485 487
486Example: fork a process and wait for it 488Example: fork a process and wait for it
487 489
488 my $done = AnyEvent->condvar; 490 my $done = AnyEvent->condvar;
489 491
503 505
504=head2 IDLE WATCHERS 506=head2 IDLE WATCHERS
505 507
506 $w = AnyEvent->idle (cb => <callback>); 508 $w = AnyEvent->idle (cb => <callback>);
507 509
508Repeatedly invoke the callback after the process becomes idle, until 510This will repeatedly invoke the callback after the process becomes idle,
509either the watcher is destroyed or new events have been detected. 511until either the watcher is destroyed or new events have been detected.
510 512
511Idle watchers are useful when there is a need to do something, but it 513Idle watchers are useful when there is a need to do something, but it
512is not so important (or wise) to do it instantly. The callback will be 514is not so important (or wise) to do it instantly. The callback will be
513invoked only when there is "nothing better to do", which is usually 515invoked only when there is "nothing better to do", which is usually
514defined as "all outstanding events have been handled and no new events 516defined as "all outstanding events have been handled and no new events
553will actively watch for new events and call your callbacks. 555will actively watch for new events and call your callbacks.
554 556
555AnyEvent is slightly different: it expects somebody else to run the event 557AnyEvent is slightly different: it expects somebody else to run the event
556loop and will only block when necessary (usually when told by the user). 558loop and will only block when necessary (usually when told by the user).
557 559
558The instrument to do that is called a "condition variable", so called 560The tool to do that is called a "condition variable", so called because
559because they represent a condition that must become true. 561they represent a condition that must become true.
560 562
561Now is probably a good time to look at the examples further below. 563Now is probably a good time to look at the examples further below.
562 564
563Condition variables can be created by calling the C<< AnyEvent->condvar 565Condition variables can be created by calling the C<< AnyEvent->condvar
564>> method, usually without arguments. The only argument pair allowed is 566>> method, usually without arguments. The only argument pair allowed is
569After creation, the condition variable is "false" until it becomes "true" 571After creation, the condition variable is "false" until it becomes "true"
570by calling the C<send> method (or calling the condition variable as if it 572by calling the C<send> method (or calling the condition variable as if it
571were a callback, read about the caveats in the description for the C<< 573were a callback, read about the caveats in the description for the C<<
572->send >> method). 574->send >> method).
573 575
574Condition variables are similar to callbacks, except that you can 576Since condition variables are the most complex part of the AnyEvent API, here are
575optionally wait for them. They can also be called merge points - points 577some different mental models of what they are - pick the ones you can connect to:
576in time where multiple outstanding events have been processed. And yet 578
577another way to call them is transactions - each condition variable can be 579=over 4
578used to represent a transaction, which finishes at some point and delivers 580
579a result. And yet some people know them as "futures" - a promise to 581=item * Condition variables are like callbacks - you can call them (and pass them instead
580compute/deliver something that you can wait for. 582of callbacks). Unlike callbacks however, you can also wait for them to be called.
583
584=item * Condition variables are signals - one side can emit or send them,
585the other side can wait for them, or install a handler that is called when
586the signal fires.
587
588=item * Condition variables are like "Merge Points" - points in your program
589where you merge multiple independent results/control flows into one.
590
591=item * Condition variables represent a transaction - functions that start
592some kind of transaction can return them, leaving the caller the choice
593between waiting in a blocking fashion, or setting a callback.
594
595=item * Condition variables represent future values, or promises to deliver
596some result, long before the result is available.
597
598=back
581 599
582Condition variables are very useful to signal that something has finished, 600Condition variables are very useful to signal that something has finished,
583for example, if you write a module that does asynchronous http requests, 601for example, if you write a module that does asynchronous http requests,
584then a condition variable would be the ideal candidate to signal the 602then a condition variable would be the ideal candidate to signal the
585availability of results. The user can either act when the callback is 603availability of results. The user can either act when the callback is
598 616
599Condition variables are represented by hash refs in perl, and the keys 617Condition variables are represented by hash refs in perl, and the keys
600used by AnyEvent itself are all named C<_ae_XXX> to make subclassing 618used by AnyEvent itself are all named C<_ae_XXX> to make subclassing
601easy (it is often useful to build your own transaction class on top of 619easy (it is often useful to build your own transaction class on top of
602AnyEvent). To subclass, use C<AnyEvent::CondVar> as base class and call 620AnyEvent). To subclass, use C<AnyEvent::CondVar> as base class and call
603it's C<new> method in your own C<new> method. 621its C<new> method in your own C<new> method.
604 622
605There are two "sides" to a condition variable - the "producer side" which 623There are two "sides" to a condition variable - the "producer side" which
606eventually calls C<< -> send >>, and the "consumer side", which waits 624eventually calls C<< -> send >>, and the "consumer side", which waits
607for the send to occur. 625for the send to occur.
608 626
609Example: wait for a timer. 627Example: wait for a timer.
610 628
611 # wait till the result is ready 629 # condition: "wait till the timer is fired"
612 my $result_ready = AnyEvent->condvar; 630 my $timer_fired = AnyEvent->condvar;
613 631
614 # do something such as adding a timer 632 # create the timer - we could wait for, say
615 # or socket watcher the calls $result_ready->send 633 # a handle becomign ready, or even an
616 # when the "result" is ready. 634 # AnyEvent::HTTP request to finish, but
617 # in this case, we simply use a timer: 635 # in this case, we simply use a timer:
618 my $w = AnyEvent->timer ( 636 my $w = AnyEvent->timer (
619 after => 1, 637 after => 1,
620 cb => sub { $result_ready->send }, 638 cb => sub { $timer_fired->send },
621 ); 639 );
622 640
623 # this "blocks" (while handling events) till the callback 641 # this "blocks" (while handling events) till the callback
624 # calls ->send 642 # calls ->send
625 $result_ready->recv; 643 $timer_fired->recv;
626 644
627Example: wait for a timer, but take advantage of the fact that condition 645Example: wait for a timer, but take advantage of the fact that condition
628variables are also callable directly. 646variables are also callable directly.
629 647
630 my $done = AnyEvent->condvar; 648 my $done = AnyEvent->condvar;
673they were a code reference). Calling them directly is the same as calling 691they were a code reference). Calling them directly is the same as calling
674C<send>. 692C<send>.
675 693
676=item $cv->croak ($error) 694=item $cv->croak ($error)
677 695
678Similar to send, but causes all call's to C<< ->recv >> to invoke 696Similar to send, but causes all calls to C<< ->recv >> to invoke
679C<Carp::croak> with the given error message/object/scalar. 697C<Carp::croak> with the given error message/object/scalar.
680 698
681This can be used to signal any errors to the condition variable 699This can be used to signal any errors to the condition variable
682user/consumer. Doing it this way instead of calling C<croak> directly 700user/consumer. Doing it this way instead of calling C<croak> directly
683delays the error detetcion, but has the overwhelmign advantage that it 701delays the error detection, but has the overwhelming advantage that it
684diagnoses the error at the place where the result is expected, and not 702diagnoses the error at the place where the result is expected, and not
685deep in some event clalback without connection to the actual code causing 703deep in some event callback with no connection to the actual code causing
686the problem. 704the problem.
687 705
688=item $cv->begin ([group callback]) 706=item $cv->begin ([group callback])
689 707
690=item $cv->end 708=item $cv->end
728one call to C<begin>, so the condvar waits for all calls to C<end> before 746one call to C<begin>, so the condvar waits for all calls to C<end> before
729sending. 747sending.
730 748
731The ping example mentioned above is slightly more complicated, as the 749The ping example mentioned above is slightly more complicated, as the
732there are results to be passwd back, and the number of tasks that are 750there are results to be passwd back, and the number of tasks that are
733begung can potentially be zero: 751begun can potentially be zero:
734 752
735 my $cv = AnyEvent->condvar; 753 my $cv = AnyEvent->condvar;
736 754
737 my %result; 755 my %result;
738 $cv->begin (sub { shift->send (\%result) }); 756 $cv->begin (sub { shift->send (\%result) });
759to be called once the counter reaches C<0>, and second, it ensures that 777to be called once the counter reaches C<0>, and second, it ensures that
760C<send> is called even when C<no> hosts are being pinged (the loop 778C<send> is called even when C<no> hosts are being pinged (the loop
761doesn't execute once). 779doesn't execute once).
762 780
763This is the general pattern when you "fan out" into multiple (but 781This is the general pattern when you "fan out" into multiple (but
764potentially none) subrequests: use an outer C<begin>/C<end> pair to set 782potentially zero) subrequests: use an outer C<begin>/C<end> pair to set
765the callback and ensure C<end> is called at least once, and then, for each 783the callback and ensure C<end> is called at least once, and then, for each
766subrequest you start, call C<begin> and for each subrequest you finish, 784subrequest you start, call C<begin> and for each subrequest you finish,
767call C<end>. 785call C<end>.
768 786
769=back 787=back
776=over 4 794=over 4
777 795
778=item $cv->recv 796=item $cv->recv
779 797
780Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak 798Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak
781>> methods have been called on c<$cv>, while servicing other watchers 799>> methods have been called on C<$cv>, while servicing other watchers
782normally. 800normally.
783 801
784You can only wait once on a condition - additional calls are valid but 802You can only wait once on a condition - additional calls are valid but
785will return immediately. 803will return immediately.
786 804
803caller decide whether the call will block or not (for example, by coupling 821caller decide whether the call will block or not (for example, by coupling
804condition variables with some kind of request results and supporting 822condition variables with some kind of request results and supporting
805callbacks so the caller knows that getting the result will not block, 823callbacks so the caller knows that getting the result will not block,
806while still supporting blocking waits if the caller so desires). 824while still supporting blocking waits if the caller so desires).
807 825
808You can ensure that C<< -recv >> never blocks by setting a callback and 826You can ensure that C<< ->recv >> never blocks by setting a callback and
809only calling C<< ->recv >> from within that callback (or at a later 827only calling C<< ->recv >> from within that callback (or at a later
810time). This will work even when the event loop does not support blocking 828time). This will work even when the event loop does not support blocking
811waits otherwise. 829waits otherwise.
812 830
813=item $bool = $cv->ready 831=item $bool = $cv->ready
818=item $cb = $cv->cb ($cb->($cv)) 836=item $cb = $cv->cb ($cb->($cv))
819 837
820This is a mutator function that returns the callback set and optionally 838This is a mutator function that returns the callback set and optionally
821replaces it before doing so. 839replaces it before doing so.
822 840
823The callback will be called when the condition becomes (or already was) 841The callback will be called when the condition becomes "true", i.e. when
824"true", i.e. when C<send> or C<croak> are called (or were called), with 842C<send> or C<croak> are called, with the only argument being the
825the only argument being the condition variable itself. Calling C<recv> 843condition variable itself. If the condition is already true, the
844callback is called immediately when it is set. Calling C<recv> inside
826inside the callback or at any later time is guaranteed not to block. 845the callback or at any later time is guaranteed not to block.
827 846
828=back 847=back
829 848
830=head1 SUPPORTED EVENT LOOPS/BACKENDS 849=head1 SUPPORTED EVENT LOOPS/BACKENDS
831 850
839use. If EV is not installed, then AnyEvent will fall back to its own 858use. If EV is not installed, then AnyEvent will fall back to its own
840pure-perl implementation, which is available everywhere as it comes with 859pure-perl implementation, which is available everywhere as it comes with
841AnyEvent itself. 860AnyEvent itself.
842 861
843 AnyEvent::Impl::EV based on EV (interface to libev, best choice). 862 AnyEvent::Impl::EV based on EV (interface to libev, best choice).
844 AnyEvent::Impl::Perl pure-perl implementation, fast and portable. 863 AnyEvent::Impl::Perl pure-perl AnyEvent::Loop, fast and portable.
845 864
846=item Backends that are transparently being picked up when they are used. 865=item Backends that are transparently being picked up when they are used.
847 866
848These will be used when they are currently loaded when the first watcher 867These will be used if they are already loaded when the first watcher
849is created, in which case it is assumed that the application is using 868is created, in which case it is assumed that the application is using
850them. This means that AnyEvent will automatically pick the right backend 869them. This means that AnyEvent will automatically pick the right backend
851when the main program loads an event module before anything starts to 870when the main program loads an event module before anything starts to
852create watchers. Nothing special needs to be done by the main program. 871create watchers. Nothing special needs to be done by the main program.
853 872
855 AnyEvent::Impl::Glib based on Glib, slow but very stable. 874 AnyEvent::Impl::Glib based on Glib, slow but very stable.
856 AnyEvent::Impl::Tk based on Tk, very broken. 875 AnyEvent::Impl::Tk based on Tk, very broken.
857 AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. 876 AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
858 AnyEvent::Impl::POE based on POE, very slow, some limitations. 877 AnyEvent::Impl::POE based on POE, very slow, some limitations.
859 AnyEvent::Impl::Irssi used when running within irssi. 878 AnyEvent::Impl::Irssi used when running within irssi.
879 AnyEvent::Impl::IOAsync based on IO::Async.
880 AnyEvent::Impl::Cocoa based on Cocoa::EventLoop.
881 AnyEvent::Impl::FLTK based on FLTK (fltk 2 binding).
860 882
861=item Backends with special needs. 883=item Backends with special needs.
862 884
863Qt requires the Qt::Application to be instantiated first, but will 885Qt requires the Qt::Application to be instantiated first, but will
864otherwise be picked up automatically. As long as the main program 886otherwise be picked up automatically. As long as the main program
865instantiates the application before any AnyEvent watchers are created, 887instantiates the application before any AnyEvent watchers are created,
866everything should just work. 888everything should just work.
867 889
868 AnyEvent::Impl::Qt based on Qt. 890 AnyEvent::Impl::Qt based on Qt.
869 891
870Support for IO::Async can only be partial, as it is too broken and
871architecturally limited to even support the AnyEvent API. It also
872is the only event loop that needs the loop to be set explicitly, so
873it can only be used by a main program knowing about AnyEvent. See
874L<AnyEvent::Impl::Async> for the gory details.
875
876 AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed.
877
878=item Event loops that are indirectly supported via other backends. 892=item Event loops that are indirectly supported via other backends.
879 893
880Some event loops can be supported via other modules: 894Some event loops can be supported via other modules:
881 895
882There is no direct support for WxWidgets (L<Wx>) or L<Prima>. 896There is no direct support for WxWidgets (L<Wx>) or L<Prima>.
907Contains C<undef> until the first watcher is being created, before the 921Contains C<undef> until the first watcher is being created, before the
908backend has been autodetected. 922backend has been autodetected.
909 923
910Afterwards it contains the event model that is being used, which is the 924Afterwards it contains the event model that is being used, which is the
911name of the Perl class implementing the model. This class is usually one 925name of the Perl class implementing the model. This class is usually one
912of the C<AnyEvent::Impl:xxx> modules, but can be any other class in the 926of the C<AnyEvent::Impl::xxx> modules, but can be any other class in the
913case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it 927case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it
914will be C<urxvt::anyevent>). 928will be C<urxvt::anyevent>).
915 929
916=item AnyEvent::detect 930=item AnyEvent::detect
917 931
918Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model 932Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model
919if necessary. You should only call this function right before you would 933if necessary. You should only call this function right before you would
920have created an AnyEvent watcher anyway, that is, as late as possible at 934have created an AnyEvent watcher anyway, that is, as late as possible at
921runtime, and not e.g. while initialising of your module. 935runtime, and not e.g. during initialisation of your module.
936
937The effect of calling this function is as if a watcher had been created
938(specifically, actions that happen "when the first watcher is created"
939happen when calling detetc as well).
922 940
923If you need to do some initialisation before AnyEvent watchers are 941If you need to do some initialisation before AnyEvent watchers are
924created, use C<post_detect>. 942created, use C<post_detect>.
925 943
926=item $guard = AnyEvent::post_detect { BLOCK } 944=item $guard = AnyEvent::post_detect { BLOCK }
927 945
928Arranges for the code block to be executed as soon as the event model is 946Arranges for the code block to be executed as soon as the event model is
929autodetected (or immediately if this has already happened). 947autodetected (or immediately if that has already happened).
930 948
931The block will be executed I<after> the actual backend has been detected 949The block will be executed I<after> the actual backend has been detected
932(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been 950(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been
933created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do 951created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do
934other initialisations - see the sources of L<AnyEvent::Strict> or 952other initialisations - see the sources of L<AnyEvent::Strict> or
943that automatically removes the callback again when it is destroyed (or 961that automatically removes the callback again when it is destroyed (or
944C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for 962C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for
945a case where this is useful. 963a case where this is useful.
946 964
947Example: Create a watcher for the IO::AIO module and store it in 965Example: Create a watcher for the IO::AIO module and store it in
948C<$WATCHER>. Only do so after the event loop is initialised, though. 966C<$WATCHER>, but do so only do so after the event loop is initialised.
949 967
950 our WATCHER; 968 our WATCHER;
951 969
952 my $guard = AnyEvent::post_detect { 970 my $guard = AnyEvent::post_detect {
953 $WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb); 971 $WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb);
961 $WATCHER ||= $guard; 979 $WATCHER ||= $guard;
962 980
963=item @AnyEvent::post_detect 981=item @AnyEvent::post_detect
964 982
965If there are any code references in this array (you can C<push> to it 983If there are any code references in this array (you can C<push> to it
966before or after loading AnyEvent), then they will called directly after 984before or after loading AnyEvent), then they will be called directly
967the event loop has been chosen. 985after the event loop has been chosen.
968 986
969You should check C<$AnyEvent::MODEL> before adding to this array, though: 987You should check C<$AnyEvent::MODEL> before adding to this array, though:
970if it is defined then the event loop has already been detected, and the 988if it is defined then the event loop has already been detected, and the
971array will be ignored. 989array will be ignored.
972 990
989 # AnyEvent not yet initialised, so make sure to load Coro::AnyEvent 1007 # AnyEvent not yet initialised, so make sure to load Coro::AnyEvent
990 # as soon as it is 1008 # as soon as it is
991 push @AnyEvent::post_detect, sub { require Coro::AnyEvent }; 1009 push @AnyEvent::post_detect, sub { require Coro::AnyEvent };
992 } 1010 }
993 1011
1012=item AnyEvent::postpone { BLOCK }
1013
1014Arranges for the block to be executed as soon as possible, but not before
1015the call itself returns. In practise, the block will be executed just
1016before the event loop polls for new events, or shortly afterwards.
1017
1018This function never returns anything (to make the C<return postpone { ...
1019}> idiom more useful.
1020
1021To understand the usefulness of this function, consider a function that
1022asynchronously does something for you and returns some transaction
1023object or guard to let you cancel the operation. For example,
1024C<AnyEvent::Socket::tcp_connect>:
1025
1026 # start a conenction attempt unless one is active
1027 $self->{connect_guard} ||= AnyEvent::Socket::tcp_connect "www.example.net", 80, sub {
1028 delete $self->{connect_guard};
1029 ...
1030 };
1031
1032Imagine that this function could instantly call the callback, for
1033example, because it detects an obvious error such as a negative port
1034number. Invoking the callback before the function returns causes problems
1035however: the callback will be called and will try to delete the guard
1036object. But since the function hasn't returned yet, there is nothing to
1037delete. When the function eventually returns it will assign the guard
1038object to C<< $self->{connect_guard} >>, where it will likely never be
1039deleted, so the program thinks it is still trying to connect.
1040
1041This is where C<AnyEvent::postpone> should be used. Instead of calling the
1042callback directly on error:
1043
1044 $cb->(undef), return # signal error to callback, BAD!
1045 if $some_error_condition;
1046
1047It should use C<postpone>:
1048
1049 AnyEvent::postpone { $cb->(undef) }, return # signal error to callback, later
1050 if $some_error_condition;
1051
1052=item AnyEvent::log $level, $msg[, @args]
1053
1054Log the given C<$msg> at the given C<$level>.
1055
1056If L<AnyEvent::Log> is not loaded then this function makes a simple test
1057to see whether the message will be logged. If the test succeeds it will
1058load AnyEvent::Log and call C<AnyEvent::Log::log> - consequently, look at
1059the L<AnyEvent::Log> documentation for details.
1060
1061If the test fails it will simply return. Right now this happens when a
1062numerical loglevel is used and it is larger than the level specified via
1063C<$ENV{PERL_ANYEVENT_VERBOSE}>.
1064
1065If you want to sprinkle loads of logging calls around your code, consider
1066creating a logger callback with the C<AnyEvent::Log::logger> function,
1067which can reduce typing, codesize and can reduce the logging overhead
1068enourmously.
1069
994=back 1070=back
995 1071
996=head1 WHAT TO DO IN A MODULE 1072=head1 WHAT TO DO IN A MODULE
997 1073
998As a module author, you should C<use AnyEvent> and call AnyEvent methods 1074As a module author, you should C<use AnyEvent> and call AnyEvent methods
1008because it will stall the whole program, and the whole point of using 1084because it will stall the whole program, and the whole point of using
1009events is to stay interactive. 1085events is to stay interactive.
1010 1086
1011It is fine, however, to call C<< ->recv >> when the user of your module 1087It is fine, however, to call C<< ->recv >> when the user of your module
1012requests it (i.e. if you create a http request object ad have a method 1088requests it (i.e. if you create a http request object ad have a method
1013called C<results> that returns the results, it should call C<< ->recv >> 1089called C<results> that returns the results, it may call C<< ->recv >>
1014freely, as the user of your module knows what she is doing. always). 1090freely, as the user of your module knows what she is doing. Always).
1015 1091
1016=head1 WHAT TO DO IN THE MAIN PROGRAM 1092=head1 WHAT TO DO IN THE MAIN PROGRAM
1017 1093
1018There will always be a single main program - the only place that should 1094There will always be a single main program - the only place that should
1019dictate which event model to use. 1095dictate which event model to use.
1020 1096
1021If it doesn't care, it can just "use AnyEvent" and use it itself, or not 1097If the program is not event-based, it need not do anything special, even
1022do anything special (it does not need to be event-based) and let AnyEvent 1098when it depends on a module that uses an AnyEvent. If the program itself
1023decide which implementation to chose if some module relies on it. 1099uses AnyEvent, but does not care which event loop is used, all it needs
1100to do is C<use AnyEvent>. In either case, AnyEvent will choose the best
1101available loop implementation.
1024 1102
1025If the main program relies on a specific event model - for example, in 1103If the main program relies on a specific event model - for example, in
1026Gtk2 programs you have to rely on the Glib module - you should load the 1104Gtk2 programs you have to rely on the Glib module - you should load the
1027event module before loading AnyEvent or any module that uses it: generally 1105event module before loading AnyEvent or any module that uses it: generally
1028speaking, you should load it as early as possible. The reason is that 1106speaking, you should load it as early as possible. The reason is that
1029modules might create watchers when they are loaded, and AnyEvent will 1107modules might create watchers when they are loaded, and AnyEvent will
1030decide on the event model to use as soon as it creates watchers, and it 1108decide on the event model to use as soon as it creates watchers, and it
1031might chose the wrong one unless you load the correct one yourself. 1109might choose the wrong one unless you load the correct one yourself.
1032 1110
1033You can chose to use a pure-perl implementation by loading the 1111You can chose to use a pure-perl implementation by loading the
1034C<AnyEvent::Impl::Perl> module, which gives you similar behaviour 1112C<AnyEvent::Loop> module, which gives you similar behaviour
1035everywhere, but letting AnyEvent chose the model is generally better. 1113everywhere, but letting AnyEvent chose the model is generally better.
1036 1114
1037=head2 MAINLOOP EMULATION 1115=head2 MAINLOOP EMULATION
1038 1116
1039Sometimes (often for short test scripts, or even standalone programs who 1117Sometimes (often for short test scripts, or even standalone programs who
1052 1130
1053 1131
1054=head1 OTHER MODULES 1132=head1 OTHER MODULES
1055 1133
1056The following is a non-exhaustive list of additional modules that use 1134The following is a non-exhaustive list of additional modules that use
1057AnyEvent as a client and can therefore be mixed easily with other AnyEvent 1135AnyEvent as a client and can therefore be mixed easily with other
1058modules and other event loops in the same program. Some of the modules 1136AnyEvent modules and other event loops in the same program. Some of the
1059come with AnyEvent, most are available via CPAN. 1137modules come as part of AnyEvent, the others are available via CPAN (see
1138L<http://search.cpan.org/search?m=module&q=anyevent%3A%3A*> for
1139a longer non-exhaustive list), and the list is heavily biased towards
1140modules of the AnyEvent author himself :)
1060 1141
1061=over 4 1142=over 4
1062 1143
1063=item L<AnyEvent::Util> 1144=item L<AnyEvent::Util>
1064 1145
1065Contains various utility functions that replace often-used but blocking 1146Contains various utility functions that replace often-used blocking
1066functions such as C<inet_aton> by event-/callback-based versions. 1147functions such as C<inet_aton> with event/callback-based versions.
1067 1148
1068=item L<AnyEvent::Socket> 1149=item L<AnyEvent::Socket>
1069 1150
1070Provides various utility functions for (internet protocol) sockets, 1151Provides various utility functions for (internet protocol) sockets,
1071addresses and name resolution. Also functions to create non-blocking tcp 1152addresses and name resolution. Also functions to create non-blocking tcp
1073 1154
1074=item L<AnyEvent::Handle> 1155=item L<AnyEvent::Handle>
1075 1156
1076Provide read and write buffers, manages watchers for reads and writes, 1157Provide read and write buffers, manages watchers for reads and writes,
1077supports raw and formatted I/O, I/O queued and fully transparent and 1158supports raw and formatted I/O, I/O queued and fully transparent and
1078non-blocking SSL/TLS (via L<AnyEvent::TLS>. 1159non-blocking SSL/TLS (via L<AnyEvent::TLS>).
1079 1160
1080=item L<AnyEvent::DNS> 1161=item L<AnyEvent::DNS>
1081 1162
1082Provides rich asynchronous DNS resolver capabilities. 1163Provides rich asynchronous DNS resolver capabilities.
1083 1164
1165=item L<AnyEvent::HTTP>, L<AnyEvent::IRC>, L<AnyEvent::XMPP>, L<AnyEvent::GPSD>, L<AnyEvent::IGS>, L<AnyEvent::FCP>
1166
1167Implement event-based interfaces to the protocols of the same name (for
1168the curious, IGS is the International Go Server and FCP is the Freenet
1169Client Protocol).
1170
1084=item L<AnyEvent::HTTP> 1171=item L<AnyEvent::AIO>
1085 1172
1086A simple-to-use HTTP library that is capable of making a lot of concurrent 1173Truly asynchronous (as opposed to non-blocking) I/O, should be in the
1087HTTP requests. 1174toolbox of every event programmer. AnyEvent::AIO transparently fuses
1175L<IO::AIO> and AnyEvent together, giving AnyEvent access to event-based
1176file I/O, and much more.
1177
1178=item L<AnyEvent::Filesys::Notify>
1179
1180AnyEvent is good for non-blocking stuff, but it can't detect file or
1181path changes (e.g. "watch this directory for new files", "watch this
1182file for changes"). The L<AnyEvent::Filesys::Notify> module promises to
1183do just that in a portbale fashion, supporting inotify on GNU/Linux and
1184some weird, without doubt broken, stuff on OS X to monitor files. It can
1185fall back to blocking scans at regular intervals transparently on other
1186platforms, so it's about as portable as it gets.
1187
1188(I haven't used it myself, but I haven't heard anybody complaining about
1189it yet).
1190
1191=item L<AnyEvent::DBI>
1192
1193Executes L<DBI> requests asynchronously in a proxy process for you,
1194notifying you in an event-based way when the operation is finished.
1088 1195
1089=item L<AnyEvent::HTTPD> 1196=item L<AnyEvent::HTTPD>
1090 1197
1091Provides a simple web application server framework. 1198A simple embedded webserver.
1092 1199
1093=item L<AnyEvent::FastPing> 1200=item L<AnyEvent::FastPing>
1094 1201
1095The fastest ping in the west. 1202The fastest ping in the west.
1096 1203
1097=item L<AnyEvent::DBI>
1098
1099Executes L<DBI> requests asynchronously in a proxy process.
1100
1101=item L<AnyEvent::AIO>
1102
1103Truly asynchronous I/O, should be in the toolbox of every event
1104programmer. AnyEvent::AIO transparently fuses L<IO::AIO> and AnyEvent
1105together.
1106
1107=item L<AnyEvent::BDB>
1108
1109Truly asynchronous Berkeley DB access. AnyEvent::BDB transparently fuses
1110L<BDB> and AnyEvent together.
1111
1112=item L<AnyEvent::GPSD>
1113
1114A non-blocking interface to gpsd, a daemon delivering GPS information.
1115
1116=item L<AnyEvent::IRC>
1117
1118AnyEvent based IRC client module family (replacing the older Net::IRC3).
1119
1120=item L<AnyEvent::XMPP>
1121
1122AnyEvent based XMPP (Jabber protocol) module family (replacing the older
1123Net::XMPP2>.
1124
1125=item L<AnyEvent::IGS>
1126
1127A non-blocking interface to the Internet Go Server protocol (used by
1128L<App::IGS>).
1129
1130=item L<Net::FCP>
1131
1132AnyEvent-based implementation of the Freenet Client Protocol, birthplace
1133of AnyEvent.
1134
1135=item L<Event::ExecFlow>
1136
1137High level API for event-based execution flow control.
1138
1139=item L<Coro> 1204=item L<Coro>
1140 1205
1141Has special support for AnyEvent via L<Coro::AnyEvent>. 1206Has special support for AnyEvent via L<Coro::AnyEvent>, which allows you
1207to simply invert the flow control - don't call us, we will call you:
1208
1209 async {
1210 Coro::AnyEvent::sleep 5; # creates a 5s timer and waits for it
1211 print "5 seconds later!\n";
1212
1213 Coro::AnyEvent::readable *STDIN; # uses an I/O watcher
1214 my $line = <STDIN>; # works for ttys
1215
1216 AnyEvent::HTTP::http_get "url", Coro::rouse_cb;
1217 my ($body, $hdr) = Coro::rouse_wait;
1218 };
1142 1219
1143=back 1220=back
1144 1221
1145=cut 1222=cut
1146 1223
1147package AnyEvent; 1224package AnyEvent;
1148 1225
1149# basically a tuned-down version of common::sense 1226# basically a tuned-down version of common::sense
1150sub common_sense { 1227sub common_sense {
1151 # from common:.sense 1.0 1228 # from common:.sense 3.4
1152 ${^WARNING_BITS} = "\xfc\x3f\x33\x00\x0f\xf3\xcf\xc0\xf3\xfc\x33\x00"; 1229 ${^WARNING_BITS} ^= ${^WARNING_BITS} ^ "\x3c\x3f\x33\x00\x0f\xf0\x0f\xc0\xf0\xfc\x33\x00";
1153 # use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl) 1230 # use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl)
1154 $^H |= 0x00000600; 1231 $^H |= 0x00000600;
1155} 1232}
1156 1233
1157BEGIN { AnyEvent::common_sense } 1234BEGIN { AnyEvent::common_sense }
1158 1235
1159use Carp (); 1236use Carp ();
1160 1237
1161our $VERSION = '5.24'; 1238our $VERSION = '6.1';
1162our $MODEL; 1239our $MODEL;
1163
1164our $AUTOLOAD;
1165our @ISA; 1240our @ISA;
1166
1167our @REGISTRY; 1241our @REGISTRY;
1168
1169our $VERBOSE; 1242our $VERBOSE;
1243our %PROTOCOL; # (ipv4|ipv6) => (1|2), higher numbers are preferred
1244our $MAX_SIGNAL_LATENCY = $ENV{PERL_ANYEVENT_MAX_SIGNAL_LATENCY} || 10; # executes after the BEGIN block below (tainting!)
1170 1245
1171BEGIN { 1246BEGIN {
1172 eval "sub CYGWIN(){" . (($^O =~ /cygwin/i) *1) . "}"; 1247 require "AnyEvent/constants.pl";
1173 eval "sub WIN32 (){" . (($^O =~ /mswin32/i)*1) . "}"; 1248
1174 eval "sub TAINT (){" . (${^TAINT} *1) . "}"; 1249 eval "sub TAINT (){" . (${^TAINT}*1) . "}";
1175 1250
1176 delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV} 1251 delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}
1177 if ${^TAINT}; 1252 if ${^TAINT};
1178 1253
1179 $VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1; 1254 $ENV{"PERL_ANYEVENT_$_"} = $ENV{"AE_$_"}
1255 for grep s/^AE_// && !exists $ENV{"PERL_ANYEVENT_$_"}, keys %ENV;
1180 1256
1181} 1257 @ENV{grep /^PERL_ANYEVENT_/, keys %ENV} = ()
1258 if ${^TAINT};
1182 1259
1183our $MAX_SIGNAL_LATENCY = 10; 1260 # $ENV{PERL_ANYEVENT_xxx} now valid
1184 1261
1185our %PROTOCOL; # (ipv4|ipv6) => (1|2), higher numbers are preferred 1262 $VERBOSE = length $ENV{PERL_ANYEVENT_VERBOSE} ? $ENV{PERL_ANYEVENT_VERBOSE}*1 : 4;
1186 1263
1187{
1188 my $idx; 1264 my $idx;
1189 $PROTOCOL{$_} = ++$idx 1265 $PROTOCOL{$_} = ++$idx
1190 for reverse split /\s*,\s*/, 1266 for reverse split /\s*,\s*/,
1191 $ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6"; 1267 $ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6";
1192} 1268}
1193 1269
1270our @post_detect;
1271
1272sub post_detect(&) {
1273 my ($cb) = @_;
1274
1275 push @post_detect, $cb;
1276
1277 defined wantarray
1278 ? bless \$cb, "AnyEvent::Util::postdetect"
1279 : ()
1280}
1281
1282sub AnyEvent::Util::postdetect::DESTROY {
1283 @post_detect = grep $_ != ${$_[0]}, @post_detect;
1284}
1285
1286our $POSTPONE_W;
1287our @POSTPONE;
1288
1289sub _postpone_exec {
1290 undef $POSTPONE_W;
1291
1292 &{ shift @POSTPONE }
1293 while @POSTPONE;
1294}
1295
1296sub postpone(&) {
1297 push @POSTPONE, shift;
1298
1299 $POSTPONE_W ||= AE::timer (0, 0, \&_postpone_exec);
1300
1301 ()
1302}
1303
1304sub log($$;@) {
1305 # only load the big bloated module when we actually are about to log something
1306 if ($_[0] <= ($VERBOSE || 1)) { # also catches non-numeric levels(!) and fatal
1307 local ($!, $@);
1308 require AnyEvent::Log; # among other things, sets $VERBOSE to 9
1309 # AnyEvent::Log overwrites this function
1310 goto &log;
1311 }
1312
1313 0 # not logged
1314}
1315
1316sub _logger($;$) {
1317 my ($level, $renabled) = @_;
1318
1319 $$renabled = $level <= $VERBOSE;
1320
1321 my $logger = [(caller)[0], $level, $renabled];
1322
1323 $AnyEvent::Log::LOGGER{$logger+0} = $logger;
1324
1325# return unless defined wantarray;
1326#
1327# require AnyEvent::Util;
1328# my $guard = AnyEvent::Util::guard (sub {
1329# # "clean up"
1330# delete $LOGGER{$logger+0};
1331# });
1332#
1333# sub {
1334# return 0 unless $$renabled;
1335#
1336# $guard if 0; # keep guard alive, but don't cause runtime overhead
1337# require AnyEvent::Log unless $AnyEvent::Log::VERSION;
1338# package AnyEvent::Log;
1339# _log ($logger->[0], $level, @_) # logger->[0] has been converted at load time
1340# }
1341}
1342
1343if (length $ENV{PERL_ANYEVENT_LOG}) {
1344 require AnyEvent::Log; # AnyEvent::Log does the thing for us
1345}
1346
1194my @models = ( 1347our @models = (
1195 [EV:: => AnyEvent::Impl::EV:: , 1], 1348 [EV:: => AnyEvent::Impl::EV::],
1196 [AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl:: , 1], 1349 [AnyEvent::Loop:: => AnyEvent::Impl::Perl::],
1197 # everything below here will not (normally) be autoprobed 1350 # everything below here will not (normally) be autoprobed
1198 # as the pureperl backend should work everywhere 1351 # as the pure perl backend should work everywhere
1199 # and is usually faster 1352 # and is usually faster
1353 [Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package, so msut be near the top
1200 [Event:: => AnyEvent::Impl::Event::, 1], 1354 [Event:: => AnyEvent::Impl::Event::], # slow, stable
1201 [Glib:: => AnyEvent::Impl::Glib:: , 1], # becomes extremely slow with many watchers 1355 [Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers
1356 # everything below here should not be autoloaded
1202 [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy 1357 [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
1203 [Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package
1204 [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles 1358 [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
1205 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program 1359 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program
1206 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza 1360 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
1207 [Wx:: => AnyEvent::Impl::POE::], 1361 [Wx:: => AnyEvent::Impl::POE::],
1208 [Prima:: => AnyEvent::Impl::POE::], 1362 [Prima:: => AnyEvent::Impl::POE::],
1209 # IO::Async is just too broken - we would need workarounds for its 1363 [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # a bitch to autodetect
1210 # byzantine signal and broken child handling, among others. 1364 [Cocoa::EventLoop:: => AnyEvent::Impl::Cocoa::],
1211 # IO::Async is rather hard to detect, as it doesn't have any 1365 [FLTK:: => AnyEvent::Impl::FLTK::],
1212 # obvious default class.
1213 [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program
1214 [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program
1215 [IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program
1216 [AnyEvent::Impl::IOAsync:: => AnyEvent::Impl::IOAsync::], # requires special main program
1217); 1366);
1218 1367
1219our %method = map +($_ => 1), 1368our @isa_hook;
1369
1370sub _isa_set {
1371 my @pkg = ("AnyEvent", (map $_->[0], grep defined, @isa_hook), $MODEL);
1372
1373 @{"$pkg[$_-1]::ISA"} = $pkg[$_]
1374 for 1 .. $#pkg;
1375
1376 grep $_ && $_->[1], @isa_hook
1377 and AE::_reset ();
1378}
1379
1380# used for hooking AnyEvent::Strict and AnyEvent::Debug::Wrap into the class hierarchy
1381sub _isa_hook($$;$) {
1382 my ($i, $pkg, $reset_ae) = @_;
1383
1384 $isa_hook[$i] = $pkg ? [$pkg, $reset_ae] : undef;
1385
1386 _isa_set;
1387}
1388
1389# all autoloaded methods reserve the complete glob, not just the method slot.
1390# due to bugs in perls method cache implementation.
1220 qw(io timer time now now_update signal child idle condvar one_event DESTROY); 1391our @methods = qw(io timer time now now_update signal child idle condvar);
1221 1392
1222our @post_detect;
1223
1224sub post_detect(&) { 1393sub detect() {
1225 my ($cb) = @_; 1394 return $MODEL if $MODEL; # some programs keep references to detect
1226 1395
1227 if ($MODEL) { 1396 # IO::Async::Loop::AnyEvent is extremely evil, refuse to work with it
1228 $cb->(); 1397 # the author knows about the problems and what it does to AnyEvent as a whole
1398 # (and the ability of others to use AnyEvent), but simply wants to abuse AnyEvent
1399 # anyway.
1400 AnyEvent::log fatal => "AnyEvent: IO::Async::Loop::AnyEvent detected - this module is broken by design,\n"
1401 . "abuses internals and breaks AnyEvent, will not continue."
1402 if exists $INC{"IO/Async/Loop/AnyEvent.pm"};
1229 1403
1230 undef 1404 local $!; # for good measure
1405 local $SIG{__DIE__}; # we use eval
1406
1407 # free some memory
1408 *detect = sub () { $MODEL };
1409 # undef &func doesn't correctly update the method cache. grmbl.
1410 # so we delete the whole glob. grmbl.
1411 # otoh, perl doesn't let me undef an active usb, but it lets me free
1412 # a glob with an active sub. hrm. i hope it works, but perl is
1413 # usually buggy in this department. sigh.
1414 delete @{"AnyEvent::"}{@methods};
1415 undef @methods;
1416
1417 if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z0-9:]+)$/) {
1418 my $model = $1;
1419 $model = "AnyEvent::Impl::$model" unless $model =~ s/::$//;
1420 if (eval "require $model") {
1421 AnyEvent::log 7 => "loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.";
1422 $MODEL = $model;
1231 } else { 1423 } else {
1232 push @post_detect, $cb; 1424 AnyEvent::log 4 => "unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@";
1233 1425 }
1234 defined wantarray
1235 ? bless \$cb, "AnyEvent::Util::postdetect"
1236 : ()
1237 } 1426 }
1238}
1239 1427
1240sub AnyEvent::Util::postdetect::DESTROY { 1428 # check for already loaded models
1241 @post_detect = grep $_ != ${$_[0]}, @post_detect;
1242}
1243
1244sub detect() {
1245 unless ($MODEL) { 1429 unless ($MODEL) {
1246 local $SIG{__DIE__}; 1430 for (@REGISTRY, @models) {
1247 1431 my ($package, $model) = @$_;
1248 if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) { 1432 if (${"$package\::VERSION"} > 0) {
1249 my $model = "AnyEvent::Impl::$1";
1250 if (eval "require $model") { 1433 if (eval "require $model") {
1434 AnyEvent::log 7 => "autodetected model '$model', using it.";
1251 $MODEL = $model; 1435 $MODEL = $model;
1252 warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2; 1436 last;
1253 } else { 1437 } else {
1254 warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE; 1438 AnyEvent::log 8 => "detected event loop $package, but cannot load '$model', skipping: $@";
1439 }
1255 } 1440 }
1256 } 1441 }
1257 1442
1258 # check for already loaded models
1259 unless ($MODEL) { 1443 unless ($MODEL) {
1444 # try to autoload a model
1260 for (@REGISTRY, @models) { 1445 for (@REGISTRY, @models) {
1261 my ($package, $model) = @$_; 1446 my ($package, $model) = @$_;
1447 if (
1448 eval "require $package"
1262 if (${"$package\::VERSION"} > 0) { 1449 and ${"$package\::VERSION"} > 0
1263 if (eval "require $model") { 1450 and eval "require $model"
1451 ) {
1452 AnyEvent::log 7 => "autoloaded model '$model', using it.";
1264 $MODEL = $model; 1453 $MODEL = $model;
1265 warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2;
1266 last; 1454 last;
1267 }
1268 } 1455 }
1269 } 1456 }
1270 1457
1271 unless ($MODEL) {
1272 # try to autoload a model
1273 for (@REGISTRY, @models) {
1274 my ($package, $model, $autoload) = @$_;
1275 if (
1276 $autoload
1277 and eval "require $package"
1278 and ${"$package\::VERSION"} > 0
1279 and eval "require $model"
1280 ) {
1281 $MODEL = $model;
1282 warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2;
1283 last;
1284 }
1285 }
1286
1287 $MODEL 1458 $MODEL
1288 or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.\n"; 1459 or AnyEvent::log fatal => "AnyEvent: backend autodetection failed - did you properly install AnyEvent?";
1289 }
1290 } 1460 }
1291
1292 push @{"$MODEL\::ISA"}, "AnyEvent::Base";
1293
1294 unshift @ISA, $MODEL;
1295
1296 require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT};
1297
1298 (shift @post_detect)->() while @post_detect;
1299 } 1461 }
1300 1462
1463 # free memory only needed for probing
1464 undef @models;
1465 undef @REGISTRY;
1466
1467 push @{"$MODEL\::ISA"}, "AnyEvent::Base";
1468
1469 # now nuke some methods that are overridden by the backend.
1470 # SUPER usage is not allowed in these.
1471 for (qw(time signal child idle)) {
1472 undef &{"AnyEvent::Base::$_"}
1473 if defined &{"$MODEL\::$_"};
1474 }
1475
1476 _isa_set;
1477
1478 # we're officially open!
1479
1480 if ($ENV{PERL_ANYEVENT_STRICT}) {
1481 require AnyEvent::Strict;
1482 }
1483
1484 if ($ENV{PERL_ANYEVENT_DEBUG_WRAP}) {
1485 require AnyEvent::Debug;
1486 AnyEvent::Debug::wrap ($ENV{PERL_ANYEVENT_DEBUG_WRAP});
1487 }
1488
1489 if (length $ENV{PERL_ANYEVENT_DEBUG_SHELL}) {
1490 require AnyEvent::Socket;
1491 require AnyEvent::Debug;
1492
1493 my $shell = $ENV{PERL_ANYEVENT_DEBUG_SHELL};
1494 $shell =~ s/\$\$/$$/g;
1495
1496 my ($host, $service) = AnyEvent::Socket::parse_hostport ($shell);
1497 $AnyEvent::Debug::SHELL = AnyEvent::Debug::shell ($host, $service);
1498 }
1499
1500 # now the anyevent environment is set up as the user told us to, so
1501 # call the actual user code - post detects
1502
1503 (shift @post_detect)->() while @post_detect;
1504 undef @post_detect;
1505
1506 *post_detect = sub(&) {
1507 shift->();
1508
1509 undef
1510 };
1511
1301 $MODEL 1512 $MODEL
1302} 1513}
1303 1514
1304sub AUTOLOAD { 1515for my $name (@methods) {
1305 (my $func = $AUTOLOAD) =~ s/.*://; 1516 *$name = sub {
1306 1517 detect;
1307 $method{$func} 1518 # we use goto because
1308 or Carp::croak "$func: not a valid method for AnyEvent objects"; 1519 # a) it makes the thunk more transparent
1309 1520 # b) it allows us to delete the thunk later
1310 detect unless $MODEL; 1521 goto &{ UNIVERSAL::can AnyEvent => "SUPER::$name" }
1311 1522 };
1312 my $class = shift;
1313 $class->$func (@_);
1314} 1523}
1315 1524
1316# utility function to dup a filehandle. this is used by many backends 1525# utility function to dup a filehandle. this is used by many backends
1317# to support binding more than one watcher per filehandle (they usually 1526# to support binding more than one watcher per filehandle (they usually
1318# allow only one watcher per fd, so we dup it to get a different one). 1527# allow only one watcher per fd, so we dup it to get a different one).
1332 1541
1333=head1 SIMPLIFIED AE API 1542=head1 SIMPLIFIED AE API
1334 1543
1335Starting with version 5.0, AnyEvent officially supports a second, much 1544Starting with version 5.0, AnyEvent officially supports a second, much
1336simpler, API that is designed to reduce the calling, typing and memory 1545simpler, API that is designed to reduce the calling, typing and memory
1337overhead. 1546overhead by using function call syntax and a fixed number of parameters.
1338 1547
1339See the L<AE> manpage for details. 1548See the L<AE> manpage for details.
1340 1549
1341=cut 1550=cut
1342 1551
1343package AE; 1552package AE;
1344 1553
1345our $VERSION = $AnyEvent::VERSION; 1554our $VERSION = $AnyEvent::VERSION;
1346 1555
1556sub _reset() {
1557 eval q{
1558 # fall back to the main API by default - backends and AnyEvent::Base
1559 # implementations can overwrite these.
1560
1347sub io($$$) { 1561 sub io($$$) {
1348 AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2]) 1562 AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])
1349} 1563 }
1350 1564
1351sub timer($$$) { 1565 sub timer($$$) {
1352 AnyEvent->timer (after => $_[0], interval => $_[1], cb => $_[2]) 1566 AnyEvent->timer (after => $_[0], interval => $_[1], cb => $_[2])
1353} 1567 }
1354 1568
1355sub signal($$) { 1569 sub signal($$) {
1356 AnyEvent->signal (signal => $_[0], cb => $_[1]) 1570 AnyEvent->signal (signal => $_[0], cb => $_[1])
1357} 1571 }
1358 1572
1359sub child($$) { 1573 sub child($$) {
1360 AnyEvent->child (pid => $_[0], cb => $_[1]) 1574 AnyEvent->child (pid => $_[0], cb => $_[1])
1361} 1575 }
1362 1576
1363sub idle($) { 1577 sub idle($) {
1364 AnyEvent->idle (cb => $_[0]) 1578 AnyEvent->idle (cb => $_[0]);
1365} 1579 }
1366 1580
1367sub cv(;&) { 1581 sub cv(;&) {
1368 AnyEvent->condvar (@_ ? (cb => $_[0]) : ()) 1582 AnyEvent->condvar (@_ ? (cb => $_[0]) : ())
1369} 1583 }
1370 1584
1371sub now() { 1585 sub now() {
1372 AnyEvent->now 1586 AnyEvent->now
1373} 1587 }
1374 1588
1375sub now_update() { 1589 sub now_update() {
1376 AnyEvent->now_update 1590 AnyEvent->now_update
1377} 1591 }
1378 1592
1379sub time() { 1593 sub time() {
1380 AnyEvent->time 1594 AnyEvent->time
1595 }
1596
1597 *postpone = \&AnyEvent::postpone;
1598 *log = \&AnyEvent::log;
1599 };
1600 die if $@;
1381} 1601}
1602
1603BEGIN { _reset }
1382 1604
1383package AnyEvent::Base; 1605package AnyEvent::Base;
1384 1606
1385# default implementations for many methods 1607# default implementations for many methods
1386 1608
1387sub _time() { 1609sub time {
1610 eval q{ # poor man's autoloading {}
1388 # probe for availability of Time::HiRes 1611 # probe for availability of Time::HiRes
1389 if (eval "use Time::HiRes (); Time::HiRes::time (); 1") { 1612 if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
1390 warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8; 1613 *time = sub { Time::HiRes::time () };
1391 *_time = \&Time::HiRes::time; 1614 *AE::time = \& Time::HiRes::time ;
1615 *now = \&time;
1616 AnyEvent::log 8 => "AnyEvent: using Time::HiRes for sub-second timing accuracy.";
1392 # if (eval "use POSIX (); (POSIX::times())... 1617 # if (eval "use POSIX (); (POSIX::times())...
1393 } else { 1618 } else {
1619 *time = sub { CORE::time };
1620 *AE::time = sub (){ CORE::time };
1621 *now = \&time;
1394 warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE; 1622 AnyEvent::log 3 => "using built-in time(), WARNING, no sub-second resolution!";
1395 *_time = sub (){ time }; # epic fail 1623 }
1396 } 1624 };
1625 die if $@;
1397 1626
1398 &_time 1627 &time
1399} 1628}
1400 1629
1401sub time { _time } 1630*now = \&time;
1402sub now { _time }
1403sub now_update { } 1631sub now_update { }
1404 1632
1633sub _poll {
1634 Carp::croak "$AnyEvent::MODEL does not support blocking waits. Caught";
1635}
1636
1405# default implementation for ->condvar 1637# default implementation for ->condvar
1638# in fact, the default should not be overwritten
1406 1639
1407sub condvar { 1640sub condvar {
1641 eval q{ # poor man's autoloading {}
1642 *condvar = sub {
1408 bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar" 1643 bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"
1644 };
1645
1646 *AE::cv = sub (;&) {
1647 bless { @_ ? (_ae_cb => shift) : () }, "AnyEvent::CondVar"
1648 };
1649 };
1650 die if $@;
1651
1652 &condvar
1409} 1653}
1410 1654
1411# default implementation for ->signal 1655# default implementation for ->signal
1412 1656
1413our $HAVE_ASYNC_INTERRUPT; 1657our $HAVE_ASYNC_INTERRUPT;
1422 1666
1423our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO); 1667our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);
1424our (%SIG_ASY, %SIG_ASY_W); 1668our (%SIG_ASY, %SIG_ASY_W);
1425our ($SIG_COUNT, $SIG_TW); 1669our ($SIG_COUNT, $SIG_TW);
1426 1670
1427sub _signal_exec {
1428 $HAVE_ASYNC_INTERRUPT
1429 ? $SIGPIPE_R->drain
1430 : sysread $SIGPIPE_R, (my $dummy), 9;
1431
1432 while (%SIG_EV) {
1433 for (keys %SIG_EV) {
1434 delete $SIG_EV{$_};
1435 $_->() for values %{ $SIG_CB{$_} || {} };
1436 }
1437 }
1438}
1439
1440# install a dummy wakeup watcher to reduce signal catching latency 1671# install a dummy wakeup watcher to reduce signal catching latency
1672# used by Impls
1441sub _sig_add() { 1673sub _sig_add() {
1442 unless ($SIG_COUNT++) { 1674 unless ($SIG_COUNT++) {
1443 # try to align timer on a full-second boundary, if possible 1675 # try to align timer on a full-second boundary, if possible
1444 my $NOW = AE::now; 1676 my $NOW = AE::now;
1445 1677
1455 undef $SIG_TW 1687 undef $SIG_TW
1456 unless --$SIG_COUNT; 1688 unless --$SIG_COUNT;
1457} 1689}
1458 1690
1459our $_sig_name_init; $_sig_name_init = sub { 1691our $_sig_name_init; $_sig_name_init = sub {
1460 eval q{ # poor man's autoloading 1692 eval q{ # poor man's autoloading {}
1461 undef $_sig_name_init; 1693 undef $_sig_name_init;
1462 1694
1463 if (_have_async_interrupt) { 1695 if (_have_async_interrupt) {
1464 *sig2num = \&Async::Interrupt::sig2num; 1696 *sig2num = \&Async::Interrupt::sig2num;
1465 *sig2name = \&Async::Interrupt::sig2name; 1697 *sig2name = \&Async::Interrupt::sig2name;
1489 1721
1490sub signal { 1722sub signal {
1491 eval q{ # poor man's autoloading {} 1723 eval q{ # poor man's autoloading {}
1492 # probe for availability of Async::Interrupt 1724 # probe for availability of Async::Interrupt
1493 if (_have_async_interrupt) { 1725 if (_have_async_interrupt) {
1494 warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8; 1726 AnyEvent::log 8 => "using Async::Interrupt for race-free signal handling.";
1495 1727
1496 $SIGPIPE_R = new Async::Interrupt::EventPipe; 1728 $SIGPIPE_R = new Async::Interrupt::EventPipe;
1497 $SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec; 1729 $SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;
1498 1730
1499 } else { 1731 } else {
1500 warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8; 1732 AnyEvent::log 8 => "using emulated perl signal handling with latency timer.";
1501
1502 require Fcntl;
1503 1733
1504 if (AnyEvent::WIN32) { 1734 if (AnyEvent::WIN32) {
1505 require AnyEvent::Util; 1735 require AnyEvent::Util;
1506 1736
1507 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe (); 1737 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
1508 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R; 1738 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R;
1509 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case 1739 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case
1510 } else { 1740 } else {
1511 pipe $SIGPIPE_R, $SIGPIPE_W; 1741 pipe $SIGPIPE_R, $SIGPIPE_W;
1512 fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R; 1742 fcntl $SIGPIPE_R, AnyEvent::F_SETFL, AnyEvent::O_NONBLOCK if $SIGPIPE_R;
1513 fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case 1743 fcntl $SIGPIPE_W, AnyEvent::F_SETFL, AnyEvent::O_NONBLOCK if $SIGPIPE_W; # just in case
1514 1744
1515 # not strictly required, as $^F is normally 2, but let's make sure... 1745 # not strictly required, as $^F is normally 2, but let's make sure...
1516 fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; 1746 fcntl $SIGPIPE_R, AnyEvent::F_SETFD, AnyEvent::FD_CLOEXEC;
1517 fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; 1747 fcntl $SIGPIPE_W, AnyEvent::F_SETFD, AnyEvent::FD_CLOEXEC;
1518 } 1748 }
1519 1749
1520 $SIGPIPE_R 1750 $SIGPIPE_R
1521 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n"; 1751 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1522 1752
1523 $SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec; 1753 $SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec;
1524 } 1754 }
1525 1755
1526 *signal = sub { 1756 *signal = $HAVE_ASYNC_INTERRUPT
1757 ? sub {
1527 my (undef, %arg) = @_; 1758 my (undef, %arg) = @_;
1528 1759
1529 my $signal = uc $arg{signal}
1530 or Carp::croak "required option 'signal' is missing";
1531
1532 if ($HAVE_ASYNC_INTERRUPT) {
1533 # async::interrupt 1760 # async::interrupt
1534
1535 $signal = sig2num $signal; 1761 my $signal = sig2num $arg{signal};
1536 $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; 1762 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1537 1763
1538 $SIG_ASY{$signal} ||= new Async::Interrupt 1764 $SIG_ASY{$signal} ||= new Async::Interrupt
1539 cb => sub { undef $SIG_EV{$signal} }, 1765 cb => sub { undef $SIG_EV{$signal} },
1540 signal => $signal, 1766 signal => $signal,
1541 pipe => [$SIGPIPE_R->filenos], 1767 pipe => [$SIGPIPE_R->filenos],
1542 pipe_autodrain => 0, 1768 pipe_autodrain => 0,
1543 ; 1769 ;
1544 1770
1545 } else { 1771 bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1772 }
1773 : sub {
1774 my (undef, %arg) = @_;
1775
1546 # pure perl 1776 # pure perl
1547
1548 # AE::Util has been loaded in signal
1549 $signal = sig2name $signal; 1777 my $signal = sig2name $arg{signal};
1550 $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; 1778 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1551 1779
1552 $SIG{$signal} ||= sub { 1780 $SIG{$signal} ||= sub {
1553 local $!; 1781 local $!;
1554 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV; 1782 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
1555 undef $SIG_EV{$signal}; 1783 undef $SIG_EV{$signal};
1556 }; 1784 };
1557 1785
1558 # can't do signal processing without introducing races in pure perl, 1786 # can't do signal processing without introducing races in pure perl,
1559 # so limit the signal latency. 1787 # so limit the signal latency.
1560 _sig_add; 1788 _sig_add;
1561 }
1562 1789
1563 bless [$signal, $arg{cb}], "AnyEvent::Base::signal" 1790 bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1791 }
1564 }; 1792 ;
1565 1793
1566 *AnyEvent::Base::signal::DESTROY = sub { 1794 *AnyEvent::Base::signal::DESTROY = sub {
1567 my ($signal, $cb) = @{$_[0]}; 1795 my ($signal, $cb) = @{$_[0]};
1568 1796
1569 _sig_del; 1797 _sig_del;
1576 # print weird messages, or just unconditionally exit 1804 # print weird messages, or just unconditionally exit
1577 # instead of getting the default action. 1805 # instead of getting the default action.
1578 undef $SIG{$signal} 1806 undef $SIG{$signal}
1579 unless keys %{ $SIG_CB{$signal} }; 1807 unless keys %{ $SIG_CB{$signal} };
1580 }; 1808 };
1809
1810 *_signal_exec = sub {
1811 $HAVE_ASYNC_INTERRUPT
1812 ? $SIGPIPE_R->drain
1813 : sysread $SIGPIPE_R, (my $dummy), 9;
1814
1815 while (%SIG_EV) {
1816 for (keys %SIG_EV) {
1817 delete $SIG_EV{$_};
1818 &$_ for values %{ $SIG_CB{$_} || {} };
1819 }
1820 }
1821 };
1581 }; 1822 };
1582 die if $@; 1823 die if $@;
1824
1583 &signal 1825 &signal
1584} 1826}
1585 1827
1586# default implementation for ->child 1828# default implementation for ->child
1587 1829
1588our %PID_CB; 1830our %PID_CB;
1589our $CHLD_W; 1831our $CHLD_W;
1590our $CHLD_DELAY_W; 1832our $CHLD_DELAY_W;
1591our $WNOHANG;
1592 1833
1834# used by many Impl's
1593sub _emit_childstatus($$) { 1835sub _emit_childstatus($$) {
1594 my (undef, $rpid, $rstatus) = @_; 1836 my (undef, $rpid, $rstatus) = @_;
1595 1837
1596 $_->($rpid, $rstatus) 1838 $_->($rpid, $rstatus)
1597 for values %{ $PID_CB{$rpid} || {} }, 1839 for values %{ $PID_CB{$rpid} || {} },
1598 values %{ $PID_CB{0} || {} }; 1840 values %{ $PID_CB{0} || {} };
1599} 1841}
1600 1842
1601sub _sigchld {
1602 my $pid;
1603
1604 AnyEvent->_emit_childstatus ($pid, $?)
1605 while ($pid = waitpid -1, $WNOHANG) > 0;
1606}
1607
1608sub child { 1843sub child {
1844 eval q{ # poor man's autoloading {}
1845 *_sigchld = sub {
1846 my $pid;
1847
1848 AnyEvent->_emit_childstatus ($pid, $?)
1849 while ($pid = waitpid -1, WNOHANG) > 0;
1850 };
1851
1852 *child = sub {
1609 my (undef, %arg) = @_; 1853 my (undef, %arg) = @_;
1610 1854
1611 defined (my $pid = $arg{pid} + 0) 1855 my $pid = $arg{pid};
1612 or Carp::croak "required option 'pid' is missing"; 1856 my $cb = $arg{cb};
1613 1857
1614 $PID_CB{$pid}{$arg{cb}} = $arg{cb}; 1858 $PID_CB{$pid}{$cb+0} = $cb;
1615 1859
1616 # WNOHANG is almost cetrainly 1 everywhere
1617 $WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/
1618 ? 1
1619 : eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1;
1620
1621 unless ($CHLD_W) { 1860 unless ($CHLD_W) {
1622 $CHLD_W = AE::signal CHLD => \&_sigchld; 1861 $CHLD_W = AE::signal CHLD => \&_sigchld;
1623 # child could be a zombie already, so make at least one round 1862 # child could be a zombie already, so make at least one round
1624 &_sigchld; 1863 &_sigchld;
1625 } 1864 }
1626 1865
1627 bless [$pid, $arg{cb}], "AnyEvent::Base::child" 1866 bless [$pid, $cb+0], "AnyEvent::Base::child"
1628} 1867 };
1629 1868
1630sub AnyEvent::Base::child::DESTROY { 1869 *AnyEvent::Base::child::DESTROY = sub {
1631 my ($pid, $cb) = @{$_[0]}; 1870 my ($pid, $icb) = @{$_[0]};
1632 1871
1633 delete $PID_CB{$pid}{$cb}; 1872 delete $PID_CB{$pid}{$icb};
1634 delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} }; 1873 delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };
1635 1874
1636 undef $CHLD_W unless keys %PID_CB; 1875 undef $CHLD_W unless keys %PID_CB;
1876 };
1877 };
1878 die if $@;
1879
1880 &child
1637} 1881}
1638 1882
1639# idle emulation is done by simply using a timer, regardless 1883# idle emulation is done by simply using a timer, regardless
1640# of whether the process is idle or not, and not letting 1884# of whether the process is idle or not, and not letting
1641# the callback use more than 50% of the time. 1885# the callback use more than 50% of the time.
1642sub idle { 1886sub idle {
1887 eval q{ # poor man's autoloading {}
1888 *idle = sub {
1643 my (undef, %arg) = @_; 1889 my (undef, %arg) = @_;
1644 1890
1645 my ($cb, $w, $rcb) = $arg{cb}; 1891 my ($cb, $w, $rcb) = $arg{cb};
1646 1892
1647 $rcb = sub { 1893 $rcb = sub {
1648 if ($cb) { 1894 if ($cb) {
1649 $w = _time; 1895 $w = AE::time;
1650 &$cb; 1896 &$cb;
1651 $w = _time - $w; 1897 $w = AE::time - $w;
1652 1898
1653 # never use more then 50% of the time for the idle watcher, 1899 # never use more then 50% of the time for the idle watcher,
1654 # within some limits 1900 # within some limits
1655 $w = 0.0001 if $w < 0.0001; 1901 $w = 0.0001 if $w < 0.0001;
1656 $w = 5 if $w > 5; 1902 $w = 5 if $w > 5;
1657 1903
1658 $w = AE::timer $w, 0, $rcb; 1904 $w = AE::timer $w, 0, $rcb;
1659 } else { 1905 } else {
1660 # clean up... 1906 # clean up...
1661 undef $w; 1907 undef $w;
1662 undef $rcb; 1908 undef $rcb;
1909 }
1910 };
1911
1912 $w = AE::timer 0.05, 0, $rcb;
1913
1914 bless \\$cb, "AnyEvent::Base::idle"
1663 } 1915 };
1916
1917 *AnyEvent::Base::idle::DESTROY = sub {
1918 undef $${$_[0]};
1919 };
1664 }; 1920 };
1921 die if $@;
1665 1922
1666 $w = AE::timer 0.05, 0, $rcb; 1923 &idle
1667
1668 bless \\$cb, "AnyEvent::Base::idle"
1669}
1670
1671sub AnyEvent::Base::idle::DESTROY {
1672 undef $${$_[0]};
1673} 1924}
1674 1925
1675package AnyEvent::CondVar; 1926package AnyEvent::CondVar;
1676 1927
1677our @ISA = AnyEvent::CondVar::Base::; 1928our @ISA = AnyEvent::CondVar::Base::;
1929
1930# only to be used for subclassing
1931sub new {
1932 my $class = shift;
1933 bless AnyEvent->condvar (@_), $class
1934}
1678 1935
1679package AnyEvent::CondVar::Base; 1936package AnyEvent::CondVar::Base;
1680 1937
1681#use overload 1938#use overload
1682# '&{}' => sub { my $self = shift; sub { $self->send (@_) } }, 1939# '&{}' => sub { my $self = shift; sub { $self->send (@_) } },
1692 1949
1693sub _send { 1950sub _send {
1694 # nop 1951 # nop
1695} 1952}
1696 1953
1954sub _wait {
1955 AnyEvent->_poll until $_[0]{_ae_sent};
1956}
1957
1697sub send { 1958sub send {
1698 my $cv = shift; 1959 my $cv = shift;
1699 $cv->{_ae_sent} = [@_]; 1960 $cv->{_ae_sent} = [@_];
1700 (delete $cv->{_ae_cb})->($cv) if $cv->{_ae_cb}; 1961 (delete $cv->{_ae_cb})->($cv) if $cv->{_ae_cb};
1701 $cv->_send; 1962 $cv->_send;
1708 1969
1709sub ready { 1970sub ready {
1710 $_[0]{_ae_sent} 1971 $_[0]{_ae_sent}
1711} 1972}
1712 1973
1713sub _wait {
1714 $WAITING
1715 and !$_[0]{_ae_sent}
1716 and Carp::croak "AnyEvent::CondVar: recursive blocking wait detected";
1717
1718 local $WAITING = 1;
1719 AnyEvent->one_event while !$_[0]{_ae_sent};
1720}
1721
1722sub recv { 1974sub recv {
1975 unless ($_[0]{_ae_sent}) {
1976 $WAITING
1977 and Carp::croak "AnyEvent::CondVar: recursive blocking wait attempted";
1978
1979 local $WAITING = 1;
1723 $_[0]->_wait; 1980 $_[0]->_wait;
1981 }
1724 1982
1725 Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak}; 1983 $_[0]{_ae_croak}
1726 wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0] 1984 and Carp::croak $_[0]{_ae_croak};
1985
1986 wantarray
1987 ? @{ $_[0]{_ae_sent} }
1988 : $_[0]{_ae_sent}[0]
1727} 1989}
1728 1990
1729sub cb { 1991sub cb {
1730 my $cv = shift; 1992 my $cv = shift;
1731 1993
1747 &{ $_[0]{_ae_end_cb} || sub { $_[0]->send } }; 2009 &{ $_[0]{_ae_end_cb} || sub { $_[0]->send } };
1748} 2010}
1749 2011
1750# undocumented/compatibility with pre-3.4 2012# undocumented/compatibility with pre-3.4
1751*broadcast = \&send; 2013*broadcast = \&send;
1752*wait = \&_wait; 2014*wait = \&recv;
1753 2015
1754=head1 ERROR AND EXCEPTION HANDLING 2016=head1 ERROR AND EXCEPTION HANDLING
1755 2017
1756In general, AnyEvent does not do any error handling - it relies on the 2018In general, AnyEvent does not do any error handling - it relies on the
1757caller to do that if required. The L<AnyEvent::Strict> module (see also 2019caller to do that if required. The L<AnyEvent::Strict> module (see also
1769$Event/EV::DIED->() >>, L<Glib> uses C<< install_exception_handler >> and 2031$Event/EV::DIED->() >>, L<Glib> uses C<< install_exception_handler >> and
1770so on. 2032so on.
1771 2033
1772=head1 ENVIRONMENT VARIABLES 2034=head1 ENVIRONMENT VARIABLES
1773 2035
1774The following environment variables are used by this module or its 2036AnyEvent supports a number of environment variables that tune the
1775submodules. 2037runtime behaviour. They are usually evaluated when AnyEvent is
2038loaded, initialised, or a submodule that uses them is loaded. Many of
2039them also cause AnyEvent to load additional modules - for example,
2040C<PERL_ANYEVENT_DEBUG_WRAP> causes the L<AnyEvent::Debug> module to be
2041loaded.
1776 2042
1777Note that AnyEvent will remove I<all> environment variables starting with 2043All the environment variables documented here start with
1778C<PERL_ANYEVENT_> from C<%ENV> when it is loaded while taint mode is 2044C<PERL_ANYEVENT_>, which is what AnyEvent considers its own
1779enabled. 2045namespace. Other modules are encouraged (but by no means required) to use
2046C<PERL_ANYEVENT_SUBMODULE> if they have registered the AnyEvent::Submodule
2047namespace on CPAN, for any submodule. For example, L<AnyEvent::HTTP> could
2048be expected to use C<PERL_ANYEVENT_HTTP_PROXY> (it should not access env
2049variables starting with C<AE_>, see below).
2050
2051All variables can also be set via the C<AE_> prefix, that is, instead
2052of setting C<PERL_ANYEVENT_VERBOSE> you can also set C<AE_VERBOSE>. In
2053case there is a clash btween anyevent and another program that uses
2054C<AE_something> you can set the corresponding C<PERL_ANYEVENT_something>
2055variable to the empty string, as those variables take precedence.
2056
2057When AnyEvent is first loaded, it copies all C<AE_xxx> env variables
2058to their C<PERL_ANYEVENT_xxx> counterpart unless that variable already
2059exists. If taint mode is on, then AnyEvent will remove I<all> environment
2060variables starting with C<PERL_ANYEVENT_> from C<%ENV> (or replace them
2061with C<undef> or the empty string, if the corresaponding C<AE_> variable
2062is set).
2063
2064The exact algorithm is currently:
2065
2066 1. if taint mode enabled, delete all PERL_ANYEVENT_xyz variables from %ENV
2067 2. copy over AE_xyz to PERL_ANYEVENT_xyz unless the latter alraedy exists
2068 3. if taint mode enabled, set all PERL_ANYEVENT_xyz variables to undef.
2069
2070This ensures that child processes will not see the C<AE_> variables.
2071
2072The following environment variables are currently known to AnyEvent:
1780 2073
1781=over 4 2074=over 4
1782 2075
1783=item C<PERL_ANYEVENT_VERBOSE> 2076=item C<PERL_ANYEVENT_VERBOSE>
1784 2077
1785By default, AnyEvent will be completely silent except in fatal 2078By default, AnyEvent will only log messages with loglevel C<3>
1786conditions. You can set this environment variable to make AnyEvent more 2079(C<critical>) or higher (see L<AnyEvent::Log>). You can set this
2080environment variable to a numerical loglevel to make AnyEvent more (or
1787talkative. 2081less) talkative.
1788 2082
2083If you want to do more than just set the global logging level
2084you should have a look at C<PERL_ANYEVENT_LOG>, which allows much more
2085complex specifications.
2086
2087When set to C<0> (C<off>), then no messages whatsoever will be logged with
2088the default logging settings.
2089
1789When set to C<1> or higher, causes AnyEvent to warn about unexpected 2090When set to C<5> or higher (C<warn>), causes AnyEvent to warn about
1790conditions, such as not being able to load the event model specified by 2091unexpected conditions, such as not being able to load the event model
1791C<PERL_ANYEVENT_MODEL>. 2092specified by C<PERL_ANYEVENT_MODEL>, or a guard callback throwing an
2093exception - this is the minimum recommended level.
1792 2094
1793When set to C<2> or higher, cause AnyEvent to report to STDERR which event 2095When set to C<7> or higher (info), cause AnyEvent to report which event model it
1794model it chooses. 2096chooses.
1795 2097
1796When set to C<8> or higher, then AnyEvent will report extra information on 2098When set to C<8> or higher (debug), then AnyEvent will report extra information on
1797which optional modules it loads and how it implements certain features. 2099which optional modules it loads and how it implements certain features.
2100
2101=item C<PERL_ANYEVENT_LOG>
2102
2103Accepts rather complex logging specifications. For example, you could log
2104all C<debug> messages of some module to stderr, warnings and above to
2105stderr, and errors and above to syslog, with:
2106
2107 PERL_ANYEVENT_LOG=Some::Module=debug,+log:filter=warn,+%syslog:%syslog=error,syslog
2108
2109For the rather extensive details, see L<AnyEvent::Log>.
2110
2111This variable is evaluated when AnyEvent (or L<AnyEvent::Log>) is loaded,
2112so will take effect even before AnyEvent has initialised itself.
2113
2114Note that specifying this environment variable causes the L<AnyEvent::Log>
2115module to be loaded, while C<PERL_ANYEVENT_VERBOSE> does not, so only
2116using the latter saves a few hundred kB of memory until the first message
2117is being logged.
1798 2118
1799=item C<PERL_ANYEVENT_STRICT> 2119=item C<PERL_ANYEVENT_STRICT>
1800 2120
1801AnyEvent does not do much argument checking by default, as thorough 2121AnyEvent does not do much argument checking by default, as thorough
1802argument checking is very costly. Setting this variable to a true value 2122argument checking is very costly. Setting this variable to a true value
1804check the arguments passed to most method calls. If it finds any problems, 2124check the arguments passed to most method calls. If it finds any problems,
1805it will croak. 2125it will croak.
1806 2126
1807In other words, enables "strict" mode. 2127In other words, enables "strict" mode.
1808 2128
1809Unlike C<use strict> (or it's modern cousin, C<< use L<common::sense> 2129Unlike C<use strict> (or its modern cousin, C<< use L<common::sense>
1810>>, it is definitely recommended to keep it off in production. Keeping 2130>>, it is definitely recommended to keep it off in production. Keeping
1811C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs 2131C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs
1812can be very useful, however. 2132can be very useful, however.
1813 2133
2134=item C<PERL_ANYEVENT_DEBUG_SHELL>
2135
2136If this env variable is nonempty, then its contents will be interpreted by
2137C<AnyEvent::Socket::parse_hostport> and C<AnyEvent::Debug::shell> (after
2138replacing every occurance of C<$$> by the process pid). The shell object
2139is saved in C<$AnyEvent::Debug::SHELL>.
2140
2141This happens when the first watcher is created.
2142
2143For example, to bind a debug shell on a unix domain socket in
2144F<< /tmp/debug<pid>.sock >>, you could use this:
2145
2146 PERL_ANYEVENT_DEBUG_SHELL=/tmp/debug\$\$.sock perlprog
2147 # connect with e.g.: socat readline /tmp/debug123.sock
2148
2149Or to bind to tcp port 4545 on localhost:
2150
2151 PERL_ANYEVENT_DEBUG_SHELL=127.0.0.1:4545 perlprog
2152 # connect with e.g.: telnet localhost 4545
2153
2154Note that creating sockets in F</tmp> or on localhost is very unsafe on
2155multiuser systems.
2156
2157=item C<PERL_ANYEVENT_DEBUG_WRAP>
2158
2159Can be set to C<0>, C<1> or C<2> and enables wrapping of all watchers for
2160debugging purposes. See C<AnyEvent::Debug::wrap> for details.
2161
1814=item C<PERL_ANYEVENT_MODEL> 2162=item C<PERL_ANYEVENT_MODEL>
1815 2163
1816This can be used to specify the event model to be used by AnyEvent, before 2164This can be used to specify the event model to be used by AnyEvent, before
1817auto detection and -probing kicks in. It must be a string consisting 2165auto detection and -probing kicks in.
1818entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended 2166
2167It normally is a string consisting entirely of ASCII letters (e.g. C<EV>
2168or C<IOAsync>). The string C<AnyEvent::Impl::> gets prepended and the
1819and the resulting module name is loaded and if the load was successful, 2169resulting module name is loaded and - if the load was successful - used as
1820used as event model. If it fails to load AnyEvent will proceed with 2170event model backend. If it fails to load then AnyEvent will proceed with
1821auto detection and -probing. 2171auto detection and -probing.
1822 2172
1823This functionality might change in future versions. 2173If the string ends with C<::> instead (e.g. C<AnyEvent::Impl::EV::>) then
2174nothing gets prepended and the module name is used as-is (hint: C<::> at
2175the end of a string designates a module name and quotes it appropriately).
1824 2176
1825For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you 2177For example, to force the pure perl model (L<AnyEvent::Loop::Perl>) you
1826could start your program like this: 2178could start your program like this:
1827 2179
1828 PERL_ANYEVENT_MODEL=Perl perl ... 2180 PERL_ANYEVENT_MODEL=Perl perl ...
1829 2181
1830=item C<PERL_ANYEVENT_PROTOCOLS> 2182=item C<PERL_ANYEVENT_PROTOCOLS>
1846but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4> 2198but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4>
1847- only support IPv4, never try to resolve or contact IPv6 2199- only support IPv4, never try to resolve or contact IPv6
1848addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or 2200addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or
1849IPv6, but prefer IPv6 over IPv4. 2201IPv6, but prefer IPv6 over IPv4.
1850 2202
2203=item C<PERL_ANYEVENT_HOSTS>
2204
2205This variable, if specified, overrides the F</etc/hosts> file used by
2206L<AnyEvent::Socket>C<::resolve_sockaddr>, i.e. hosts aliases will be read
2207from that file instead.
2208
1851=item C<PERL_ANYEVENT_EDNS0> 2209=item C<PERL_ANYEVENT_EDNS0>
1852 2210
1853Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension 2211Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension for
1854for DNS. This extension is generally useful to reduce DNS traffic, but 2212DNS. This extension is generally useful to reduce DNS traffic, especially
1855some (broken) firewalls drop such DNS packets, which is why it is off by 2213when DNSSEC is involved, but some (broken) firewalls drop such DNS
1856default. 2214packets, which is why it is off by default.
1857 2215
1858Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce 2216Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce
1859EDNS0 in its DNS requests. 2217EDNS0 in its DNS requests.
1860 2218
1861=item C<PERL_ANYEVENT_MAX_FORKS> 2219=item C<PERL_ANYEVENT_MAX_FORKS>
1867 2225
1868The default value for the C<max_outstanding> parameter for the default DNS 2226The default value for the C<max_outstanding> parameter for the default DNS
1869resolver - this is the maximum number of parallel DNS requests that are 2227resolver - this is the maximum number of parallel DNS requests that are
1870sent to the DNS server. 2228sent to the DNS server.
1871 2229
2230=item C<PERL_ANYEVENT_MAX_SIGNAL_LATENCY>
2231
2232Perl has inherently racy signal handling (you can basically choose between
2233losing signals and memory corruption) - pure perl event loops (including
2234C<AnyEvent::Loop>, when C<Async::Interrupt> isn't available) therefore
2235have to poll regularly to avoid losing signals.
2236
2237Some event loops are racy, but don't poll regularly, and some event loops
2238are written in C but are still racy. For those event loops, AnyEvent
2239installs a timer that regularly wakes up the event loop.
2240
2241By default, the interval for this timer is C<10> seconds, but you can
2242override this delay with this environment variable (or by setting
2243the C<$AnyEvent::MAX_SIGNAL_LATENCY> variable before creating signal
2244watchers).
2245
2246Lower values increase CPU (and energy) usage, higher values can introduce
2247long delays when reaping children or waiting for signals.
2248
2249The L<AnyEvent::Async> module, if available, will be used to avoid this
2250polling (with most event loops).
2251
1872=item C<PERL_ANYEVENT_RESOLV_CONF> 2252=item C<PERL_ANYEVENT_RESOLV_CONF>
1873 2253
1874The file to use instead of F</etc/resolv.conf> (or OS-specific 2254The absolute path to a F<resolv.conf>-style file to use instead of
1875configuration) in the default resolver. When set to the empty string, no 2255F</etc/resolv.conf> (or the OS-specific configuration) in the default
1876default config will be used. 2256resolver, or the empty string to select the default configuration.
1877 2257
1878=item C<PERL_ANYEVENT_CA_FILE>, C<PERL_ANYEVENT_CA_PATH>. 2258=item C<PERL_ANYEVENT_CA_FILE>, C<PERL_ANYEVENT_CA_PATH>.
1879 2259
1880When neither C<ca_file> nor C<ca_path> was specified during 2260When neither C<ca_file> nor C<ca_path> was specified during
1881L<AnyEvent::TLS> context creation, and either of these environment 2261L<AnyEvent::TLS> context creation, and either of these environment
1882variables exist, they will be used to specify CA certificate locations 2262variables are nonempty, they will be used to specify CA certificate
1883instead of a system-dependent default. 2263locations instead of a system-dependent default.
1884 2264
1885=item C<PERL_ANYEVENT_AVOID_GUARD> and C<PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT> 2265=item C<PERL_ANYEVENT_AVOID_GUARD> and C<PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT>
1886 2266
1887When these are set to C<1>, then the respective modules are not 2267When these are set to C<1>, then the respective modules are not
1888loaded. Mostly good for testing AnyEvent itself. 2268loaded. Mostly good for testing AnyEvent itself.
2036 2416
2037The actual code goes further and collects all errors (C<die>s, exceptions) 2417The actual code goes further and collects all errors (C<die>s, exceptions)
2038that occurred during request processing. The C<result> method detects 2418that occurred during request processing. The C<result> method detects
2039whether an exception as thrown (it is stored inside the $txn object) 2419whether an exception as thrown (it is stored inside the $txn object)
2040and just throws the exception, which means connection errors and other 2420and just throws the exception, which means connection errors and other
2041problems get reported tot he code that tries to use the result, not in a 2421problems get reported to the code that tries to use the result, not in a
2042random callback. 2422random callback.
2043 2423
2044All of this enables the following usage styles: 2424All of this enables the following usage styles:
2045 2425
20461. Blocking: 24261. Blocking:
2220(even when used without AnyEvent), but most event loops have acceptable 2600(even when used without AnyEvent), but most event loops have acceptable
2221performance with or without AnyEvent. 2601performance with or without AnyEvent.
2222 2602
2223=item * The overhead AnyEvent adds is usually much smaller than the overhead of 2603=item * The overhead AnyEvent adds is usually much smaller than the overhead of
2224the actual event loop, only with extremely fast event loops such as EV 2604the actual event loop, only with extremely fast event loops such as EV
2225adds AnyEvent significant overhead. 2605does AnyEvent add significant overhead.
2226 2606
2227=item * You should avoid POE like the plague if you want performance or 2607=item * You should avoid POE like the plague if you want performance or
2228reasonable memory usage. 2608reasonable memory usage.
2229 2609
2230=back 2610=back
2460 unless defined $SIG{PIPE}; 2840 unless defined $SIG{PIPE};
2461 2841
2462=head1 RECOMMENDED/OPTIONAL MODULES 2842=head1 RECOMMENDED/OPTIONAL MODULES
2463 2843
2464One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and 2844One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and
2465it's built-in modules) are required to use it. 2845its built-in modules) are required to use it.
2466 2846
2467That does not mean that AnyEvent won't take advantage of some additional 2847That does not mean that AnyEvent won't take advantage of some additional
2468modules if they are installed. 2848modules if they are installed.
2469 2849
2470This section explains which additional modules will be used, and how they 2850This section explains which additional modules will be used, and how they
2503automatic timer adjustments even when no monotonic clock is available, 2883automatic timer adjustments even when no monotonic clock is available,
2504can take avdantage of advanced kernel interfaces such as C<epoll> and 2884can take avdantage of advanced kernel interfaces such as C<epoll> and
2505C<kqueue>, and is the fastest backend I<by far>. You can even embed 2885C<kqueue>, and is the fastest backend I<by far>. You can even embed
2506L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>). 2886L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>).
2507 2887
2888If you only use backends that rely on another event loop (e.g. C<Tk>),
2889then this module will do nothing for you.
2890
2508=item L<Guard> 2891=item L<Guard>
2509 2892
2510The guard module, when used, will be used to implement 2893The guard module, when used, will be used to implement
2511C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a 2894C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a
2512lot less memory), but otherwise doesn't affect guard operation much. It is 2895lot less memory), but otherwise doesn't affect guard operation much. It is
2513purely used for performance. 2896purely used for performance.
2514 2897
2515=item L<JSON> and L<JSON::XS> 2898=item L<JSON> and L<JSON::XS>
2516 2899
2517One of these modules is required when you want to read or write JSON data 2900One of these modules is required when you want to read or write JSON data
2518via L<AnyEvent::Handle>. It is also written in pure-perl, but can take 2901via L<AnyEvent::Handle>. L<JSON> is also written in pure-perl, but can take
2519advantage of the ultra-high-speed L<JSON::XS> module when it is installed. 2902advantage of the ultra-high-speed L<JSON::XS> module when it is installed.
2520
2521In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is
2522installed.
2523 2903
2524=item L<Net::SSLeay> 2904=item L<Net::SSLeay>
2525 2905
2526Implementing TLS/SSL in Perl is certainly interesting, but not very 2906Implementing TLS/SSL in Perl is certainly interesting, but not very
2527worthwhile: If this module is installed, then L<AnyEvent::Handle> (with 2907worthwhile: If this module is installed, then L<AnyEvent::Handle> (with
2528the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL. 2908the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL.
2529 2909
2530=item L<Time::HiRes> 2910=item L<Time::HiRes>
2531 2911
2532This module is part of perl since release 5.008. It will be used when the 2912This module is part of perl since release 5.008. It will be used when the
2533chosen event library does not come with a timing source on it's own. The 2913chosen event library does not come with a timing source of its own. The
2534pure-perl event loop (L<AnyEvent::Impl::Perl>) will additionally use it to 2914pure-perl event loop (L<AnyEvent::Loop>) will additionally load it to
2535try to use a monotonic clock for timing stability. 2915try to use a monotonic clock for timing stability.
2536 2916
2537=back 2917=back
2538 2918
2539 2919
2601pronounced). 2981pronounced).
2602 2982
2603 2983
2604=head1 SEE ALSO 2984=head1 SEE ALSO
2605 2985
2606Utility functions: L<AnyEvent::Util>. 2986Tutorial/Introduction: L<AnyEvent::Intro>.
2607 2987
2608Event modules: L<EV>, L<EV::Glib>, L<Glib::EV>, L<Event>, L<Glib::Event>, 2988FAQ: L<AnyEvent::FAQ>.
2609L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. 2989
2990Utility functions: L<AnyEvent::Util> (misc. grab-bag), L<AnyEvent::Log>
2991(simply logging).
2992
2993Development/Debugging: L<AnyEvent::Strict> (stricter checking),
2994L<AnyEvent::Debug> (interactive shell, watcher tracing).
2995
2996Supported event modules: L<AnyEvent::Loop>, L<EV>, L<EV::Glib>,
2997L<Glib::EV>, L<Event>, L<Glib::Event>, L<Glib>, L<Tk>, L<Event::Lib>,
2998L<Qt>, L<POE>, L<FLTK>.
2610 2999
2611Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>, 3000Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,
2612L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>, 3001L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,
2613L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>, 3002L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,
2614L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>. 3003L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>,
3004L<AnyEvent::Impl::FLTK>.
2615 3005
2616Non-blocking file handles, sockets, TCP clients and 3006Non-blocking handles, pipes, stream sockets, TCP clients and
2617servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>. 3007servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.
2618 3008
2619Asynchronous DNS: L<AnyEvent::DNS>. 3009Asynchronous DNS: L<AnyEvent::DNS>.
2620 3010
2621Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, 3011Thread support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>.
2622L<Coro::Event>,
2623 3012
2624Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::XMPP>, 3013Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::IRC>,
2625L<AnyEvent::HTTP>. 3014L<AnyEvent::HTTP>.
2626 3015
2627 3016
2628=head1 AUTHOR 3017=head1 AUTHOR
2629 3018

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