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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 L<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) });
745 }; 763 };
746 } 764 }
747 765
748 $cv->end; 766 $cv->end;
749 767
768 ...
769
770 my $results = $cv->recv;
771
750This code fragment supposedly pings a number of hosts and calls 772This code fragment supposedly pings a number of hosts and calls
751C<send> after results for all then have have been gathered - in any 773C<send> after results for all then have have been gathered - in any
752order. To achieve this, the code issues a call to C<begin> when it starts 774order. To achieve this, the code issues a call to C<begin> when it starts
753each ping request and calls C<end> when it has received some result for 775each ping request and calls C<end> when it has received some result for
754it. Since C<begin> and C<end> only maintain a counter, the order in which 776it. Since C<begin> and C<end> only maintain a counter, the order in which
759to be called once the counter reaches C<0>, and second, it ensures that 781to 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 782C<send> is called even when C<no> hosts are being pinged (the loop
761doesn't execute once). 783doesn't execute once).
762 784
763This is the general pattern when you "fan out" into multiple (but 785This is the general pattern when you "fan out" into multiple (but
764potentially none) subrequests: use an outer C<begin>/C<end> pair to set 786potentially 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 787the 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, 788subrequest you start, call C<begin> and for each subrequest you finish,
767call C<end>. 789call C<end>.
768 790
769=back 791=back
776=over 4 798=over 4
777 799
778=item $cv->recv 800=item $cv->recv
779 801
780Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak 802Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak
781>> methods have been called on c<$cv>, while servicing other watchers 803>> methods have been called on C<$cv>, while servicing other watchers
782normally. 804normally.
783 805
784You can only wait once on a condition - additional calls are valid but 806You can only wait once on a condition - additional calls are valid but
785will return immediately. 807will return immediately.
786 808
789 811
790In list context, all parameters passed to C<send> will be returned, 812In list context, all parameters passed to C<send> will be returned,
791in scalar context only the first one will be returned. 813in scalar context only the first one will be returned.
792 814
793Note that doing a blocking wait in a callback is not supported by any 815Note that doing a blocking wait in a callback is not supported by any
794event loop, that is, recursive invocation of a blocking C<< ->recv 816event loop, that is, recursive invocation of a blocking C<< ->recv >> is
795>> is not allowed, and the C<recv> call will C<croak> if such a 817not allowed and the C<recv> call will C<croak> if such a condition is
796condition is detected. This condition can be slightly loosened by using 818detected. This requirement can be dropped by relying on L<Coro::AnyEvent>
797L<Coro::AnyEvent>, which allows you to do a blocking C<< ->recv >> from 819, which allows you to do a blocking C<< ->recv >> from any thread
798any thread that doesn't run the event loop itself. 820that doesn't run the event loop itself. L<Coro::AnyEvent> is loaded
821automatically when L<Coro> is used with L<AnyEvent>, so code does not need
822to do anything special to take advantage of that: any code that would
823normally block your program because it calls C<recv>, be executed in an
824C<async> thread instead without blocking other threads.
799 825
800Not all event models support a blocking wait - some die in that case 826Not all event models support a blocking wait - some die in that case
801(programs might want to do that to stay interactive), so I<if you are 827(programs might want to do that to stay interactive), so I<if you are
802using this from a module, never require a blocking wait>. Instead, let the 828using this from a module, never require a blocking wait>. Instead, let the
803caller decide whether the call will block or not (for example, by coupling 829caller decide whether the call will block or not (for example, by coupling
804condition variables with some kind of request results and supporting 830condition variables with some kind of request results and supporting
805callbacks so the caller knows that getting the result will not block, 831callbacks so the caller knows that getting the result will not block,
806while still supporting blocking waits if the caller so desires). 832while still supporting blocking waits if the caller so desires).
807 833
808You can ensure that C<< -recv >> never blocks by setting a callback and 834You can ensure that C<< ->recv >> never blocks by setting a callback and
809only calling C<< ->recv >> from within that callback (or at a later 835only calling C<< ->recv >> from within that callback (or at a later
810time). This will work even when the event loop does not support blocking 836time). This will work even when the event loop does not support blocking
811waits otherwise. 837waits otherwise.
812 838
813=item $bool = $cv->ready 839=item $bool = $cv->ready
818=item $cb = $cv->cb ($cb->($cv)) 844=item $cb = $cv->cb ($cb->($cv))
819 845
820This is a mutator function that returns the callback set and optionally 846This is a mutator function that returns the callback set and optionally
821replaces it before doing so. 847replaces it before doing so.
822 848
823The callback will be called when the condition becomes (or already was) 849The 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 850C<send> or C<croak> are called, with the only argument being the
825the only argument being the condition variable itself. Calling C<recv> 851condition variable itself. If the condition is already true, the
852callback is called immediately when it is set. Calling C<recv> inside
826inside the callback or at any later time is guaranteed not to block. 853the callback or at any later time is guaranteed not to block.
827 854
828=back 855=back
829 856
830=head1 SUPPORTED EVENT LOOPS/BACKENDS 857=head1 SUPPORTED EVENT LOOPS/BACKENDS
831 858
839use. If EV is not installed, then AnyEvent will fall back to its own 866use. If EV is not installed, then AnyEvent will fall back to its own
840pure-perl implementation, which is available everywhere as it comes with 867pure-perl implementation, which is available everywhere as it comes with
841AnyEvent itself. 868AnyEvent itself.
842 869
843 AnyEvent::Impl::EV based on EV (interface to libev, best choice). 870 AnyEvent::Impl::EV based on EV (interface to libev, best choice).
844 AnyEvent::Impl::Perl pure-perl implementation, fast and portable. 871 AnyEvent::Impl::Perl pure-perl AnyEvent::Loop, fast and portable.
845 872
846=item Backends that are transparently being picked up when they are used. 873=item Backends that are transparently being picked up when they are used.
847 874
848These will be used when they are currently loaded when the first watcher 875These 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 876is created, in which case it is assumed that the application is using
850them. This means that AnyEvent will automatically pick the right backend 877them. This means that AnyEvent will automatically pick the right backend
851when the main program loads an event module before anything starts to 878when the main program loads an event module before anything starts to
852create watchers. Nothing special needs to be done by the main program. 879create watchers. Nothing special needs to be done by the main program.
853 880
855 AnyEvent::Impl::Glib based on Glib, slow but very stable. 882 AnyEvent::Impl::Glib based on Glib, slow but very stable.
856 AnyEvent::Impl::Tk based on Tk, very broken. 883 AnyEvent::Impl::Tk based on Tk, very broken.
857 AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. 884 AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
858 AnyEvent::Impl::POE based on POE, very slow, some limitations. 885 AnyEvent::Impl::POE based on POE, very slow, some limitations.
859 AnyEvent::Impl::Irssi used when running within irssi. 886 AnyEvent::Impl::Irssi used when running within irssi.
887 AnyEvent::Impl::IOAsync based on IO::Async.
888 AnyEvent::Impl::Cocoa based on Cocoa::EventLoop.
889 AnyEvent::Impl::FLTK based on FLTK (fltk 2 binding).
860 890
861=item Backends with special needs. 891=item Backends with special needs.
862 892
863Qt requires the Qt::Application to be instantiated first, but will 893Qt requires the Qt::Application to be instantiated first, but will
864otherwise be picked up automatically. As long as the main program 894otherwise be picked up automatically. As long as the main program
865instantiates the application before any AnyEvent watchers are created, 895instantiates the application before any AnyEvent watchers are created,
866everything should just work. 896everything should just work.
867 897
868 AnyEvent::Impl::Qt based on Qt. 898 AnyEvent::Impl::Qt based on Qt.
869 899
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. 900=item Event loops that are indirectly supported via other backends.
879 901
880Some event loops can be supported via other modules: 902Some event loops can be supported via other modules:
881 903
882There is no direct support for WxWidgets (L<Wx>) or L<Prima>. 904There is no direct support for WxWidgets (L<Wx>) or L<Prima>.
907Contains C<undef> until the first watcher is being created, before the 929Contains C<undef> until the first watcher is being created, before the
908backend has been autodetected. 930backend has been autodetected.
909 931
910Afterwards it contains the event model that is being used, which is the 932Afterwards 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 933name 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 934of 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 935case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it
914will be C<urxvt::anyevent>). 936will be C<urxvt::anyevent>).
915 937
916=item AnyEvent::detect 938=item AnyEvent::detect
917 939
918Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model 940Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model
919if necessary. You should only call this function right before you would 941if necessary. You should only call this function right before you would
920have created an AnyEvent watcher anyway, that is, as late as possible at 942have created an AnyEvent watcher anyway, that is, as late as possible at
921runtime, and not e.g. while initialising of your module. 943runtime, and not e.g. during initialisation of your module.
944
945The effect of calling this function is as if a watcher had been created
946(specifically, actions that happen "when the first watcher is created"
947happen when calling detetc as well).
922 948
923If you need to do some initialisation before AnyEvent watchers are 949If you need to do some initialisation before AnyEvent watchers are
924created, use C<post_detect>. 950created, use C<post_detect>.
925 951
926=item $guard = AnyEvent::post_detect { BLOCK } 952=item $guard = AnyEvent::post_detect { BLOCK }
927 953
928Arranges for the code block to be executed as soon as the event model is 954Arranges for the code block to be executed as soon as the event model is
929autodetected (or immediately if this has already happened). 955autodetected (or immediately if that has already happened).
930 956
931The block will be executed I<after> the actual backend has been detected 957The block will be executed I<after> the actual backend has been detected
932(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been 958(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been
933created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do 959created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do
934other initialisations - see the sources of L<AnyEvent::Strict> or 960other initialisations - see the sources of L<AnyEvent::Strict> or
943that automatically removes the callback again when it is destroyed (or 969that automatically removes the callback again when it is destroyed (or
944C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for 970C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for
945a case where this is useful. 971a case where this is useful.
946 972
947Example: Create a watcher for the IO::AIO module and store it in 973Example: Create a watcher for the IO::AIO module and store it in
948C<$WATCHER>. Only do so after the event loop is initialised, though. 974C<$WATCHER>, but do so only do so after the event loop is initialised.
949 975
950 our WATCHER; 976 our WATCHER;
951 977
952 my $guard = AnyEvent::post_detect { 978 my $guard = AnyEvent::post_detect {
953 $WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb); 979 $WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb);
961 $WATCHER ||= $guard; 987 $WATCHER ||= $guard;
962 988
963=item @AnyEvent::post_detect 989=item @AnyEvent::post_detect
964 990
965If there are any code references in this array (you can C<push> to it 991If there are any code references in this array (you can C<push> to it
966before or after loading AnyEvent), then they will called directly after 992before or after loading AnyEvent), then they will be called directly
967the event loop has been chosen. 993after the event loop has been chosen.
968 994
969You should check C<$AnyEvent::MODEL> before adding to this array, though: 995You 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 996if it is defined then the event loop has already been detected, and the
971array will be ignored. 997array will be ignored.
972 998
989 # AnyEvent not yet initialised, so make sure to load Coro::AnyEvent 1015 # AnyEvent not yet initialised, so make sure to load Coro::AnyEvent
990 # as soon as it is 1016 # as soon as it is
991 push @AnyEvent::post_detect, sub { require Coro::AnyEvent }; 1017 push @AnyEvent::post_detect, sub { require Coro::AnyEvent };
992 } 1018 }
993 1019
1020=item AnyEvent::postpone { BLOCK }
1021
1022Arranges for the block to be executed as soon as possible, but not before
1023the call itself returns. In practise, the block will be executed just
1024before the event loop polls for new events, or shortly afterwards.
1025
1026This function never returns anything (to make the C<return postpone { ...
1027}> idiom more useful.
1028
1029To understand the usefulness of this function, consider a function that
1030asynchronously does something for you and returns some transaction
1031object or guard to let you cancel the operation. For example,
1032C<AnyEvent::Socket::tcp_connect>:
1033
1034 # start a conenction attempt unless one is active
1035 $self->{connect_guard} ||= AnyEvent::Socket::tcp_connect "www.example.net", 80, sub {
1036 delete $self->{connect_guard};
1037 ...
1038 };
1039
1040Imagine that this function could instantly call the callback, for
1041example, because it detects an obvious error such as a negative port
1042number. Invoking the callback before the function returns causes problems
1043however: the callback will be called and will try to delete the guard
1044object. But since the function hasn't returned yet, there is nothing to
1045delete. When the function eventually returns it will assign the guard
1046object to C<< $self->{connect_guard} >>, where it will likely never be
1047deleted, so the program thinks it is still trying to connect.
1048
1049This is where C<AnyEvent::postpone> should be used. Instead of calling the
1050callback directly on error:
1051
1052 $cb->(undef), return # signal error to callback, BAD!
1053 if $some_error_condition;
1054
1055It should use C<postpone>:
1056
1057 AnyEvent::postpone { $cb->(undef) }, return # signal error to callback, later
1058 if $some_error_condition;
1059
1060=item AnyEvent::log $level, $msg[, @args]
1061
1062Log the given C<$msg> at the given C<$level>.
1063
1064If L<AnyEvent::Log> is not loaded then this function makes a simple test
1065to see whether the message will be logged. If the test succeeds it will
1066load AnyEvent::Log and call C<AnyEvent::Log::log> - consequently, look at
1067the L<AnyEvent::Log> documentation for details.
1068
1069If the test fails it will simply return. Right now this happens when a
1070numerical loglevel is used and it is larger than the level specified via
1071C<$ENV{PERL_ANYEVENT_VERBOSE}>.
1072
1073If you want to sprinkle loads of logging calls around your code, consider
1074creating a logger callback with the C<AnyEvent::Log::logger> function,
1075which can reduce typing, codesize and can reduce the logging overhead
1076enourmously.
1077
994=back 1078=back
995 1079
996=head1 WHAT TO DO IN A MODULE 1080=head1 WHAT TO DO IN A MODULE
997 1081
998As a module author, you should C<use AnyEvent> and call AnyEvent methods 1082As 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 1092because it will stall the whole program, and the whole point of using
1009events is to stay interactive. 1093events is to stay interactive.
1010 1094
1011It is fine, however, to call C<< ->recv >> when the user of your module 1095It 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 1096requests 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 >> 1097called C<results> that returns the results, it may call C<< ->recv >>
1014freely, as the user of your module knows what she is doing. always). 1098freely, as the user of your module knows what she is doing. Always).
1015 1099
1016=head1 WHAT TO DO IN THE MAIN PROGRAM 1100=head1 WHAT TO DO IN THE MAIN PROGRAM
1017 1101
1018There will always be a single main program - the only place that should 1102There will always be a single main program - the only place that should
1019dictate which event model to use. 1103dictate which event model to use.
1020 1104
1021If it doesn't care, it can just "use AnyEvent" and use it itself, or not 1105If 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 1106when it depends on a module that uses an AnyEvent. If the program itself
1023decide which implementation to chose if some module relies on it. 1107uses AnyEvent, but does not care which event loop is used, all it needs
1108to do is C<use AnyEvent>. In either case, AnyEvent will choose the best
1109available loop implementation.
1024 1110
1025If the main program relies on a specific event model - for example, in 1111If 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 1112Gtk2 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 1113event module before loading AnyEvent or any module that uses it: generally
1028speaking, you should load it as early as possible. The reason is that 1114speaking, you should load it as early as possible. The reason is that
1029modules might create watchers when they are loaded, and AnyEvent will 1115modules 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 1116decide 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. 1117might choose the wrong one unless you load the correct one yourself.
1032 1118
1033You can chose to use a pure-perl implementation by loading the 1119You can chose to use a pure-perl implementation by loading the
1034C<AnyEvent::Impl::Perl> module, which gives you similar behaviour 1120C<AnyEvent::Loop> module, which gives you similar behaviour
1035everywhere, but letting AnyEvent chose the model is generally better. 1121everywhere, but letting AnyEvent chose the model is generally better.
1036 1122
1037=head2 MAINLOOP EMULATION 1123=head2 MAINLOOP EMULATION
1038 1124
1039Sometimes (often for short test scripts, or even standalone programs who 1125Sometimes (often for short test scripts, or even standalone programs who
1052 1138
1053 1139
1054=head1 OTHER MODULES 1140=head1 OTHER MODULES
1055 1141
1056The following is a non-exhaustive list of additional modules that use 1142The following is a non-exhaustive list of additional modules that use
1057AnyEvent as a client and can therefore be mixed easily with other AnyEvent 1143AnyEvent as a client and can therefore be mixed easily with other
1058modules and other event loops in the same program. Some of the modules 1144AnyEvent modules and other event loops in the same program. Some of the
1059come with AnyEvent, most are available via CPAN. 1145modules come as part of AnyEvent, the others are available via CPAN (see
1146L<http://search.cpan.org/search?m=module&q=anyevent%3A%3A*> for
1147a longer non-exhaustive list), and the list is heavily biased towards
1148modules of the AnyEvent author himself :)
1060 1149
1061=over 4 1150=over 4
1062 1151
1063=item L<AnyEvent::Util> 1152=item L<AnyEvent::Util> (part of the AnyEvent distribution)
1064 1153
1065Contains various utility functions that replace often-used but blocking 1154Contains various utility functions that replace often-used blocking
1066functions such as C<inet_aton> by event-/callback-based versions. 1155functions such as C<inet_aton> with event/callback-based versions.
1067 1156
1068=item L<AnyEvent::Socket> 1157=item L<AnyEvent::Socket> (part of the AnyEvent distribution)
1069 1158
1070Provides various utility functions for (internet protocol) sockets, 1159Provides various utility functions for (internet protocol) sockets,
1071addresses and name resolution. Also functions to create non-blocking tcp 1160addresses and name resolution. Also functions to create non-blocking tcp
1072connections or tcp servers, with IPv6 and SRV record support and more. 1161connections or tcp servers, with IPv6 and SRV record support and more.
1073 1162
1074=item L<AnyEvent::Handle> 1163=item L<AnyEvent::Handle> (part of the AnyEvent distribution)
1075 1164
1076Provide read and write buffers, manages watchers for reads and writes, 1165Provide read and write buffers, manages watchers for reads and writes,
1077supports raw and formatted I/O, I/O queued and fully transparent and 1166supports raw and formatted I/O, I/O queued and fully transparent and
1078non-blocking SSL/TLS (via L<AnyEvent::TLS>. 1167non-blocking SSL/TLS (via L<AnyEvent::TLS>).
1079 1168
1080=item L<AnyEvent::DNS> 1169=item L<AnyEvent::DNS> (part of the AnyEvent distribution)
1081 1170
1082Provides rich asynchronous DNS resolver capabilities. 1171Provides rich asynchronous DNS resolver capabilities.
1083 1172
1173=item L<AnyEvent::HTTP>, L<AnyEvent::IRC>, L<AnyEvent::XMPP>, L<AnyEvent::GPSD>, L<AnyEvent::IGS>, L<AnyEvent::FCP>
1174
1175Implement event-based interfaces to the protocols of the same name (for
1176the curious, IGS is the International Go Server and FCP is the Freenet
1177Client Protocol).
1178
1179=item L<AnyEvent::AIO> (part of the AnyEvent distribution)
1180
1181Truly asynchronous (as opposed to non-blocking) I/O, should be in the
1182toolbox of every event programmer. AnyEvent::AIO transparently fuses
1183L<IO::AIO> and AnyEvent together, giving AnyEvent access to event-based
1184file I/O, and much more.
1185
1186=item L<AnyEvent::Filesys::Notify>
1187
1188AnyEvent is good for non-blocking stuff, but it can't detect file or
1189path changes (e.g. "watch this directory for new files", "watch this
1190file for changes"). The L<AnyEvent::Filesys::Notify> module promises to
1191do just that in a portbale fashion, supporting inotify on GNU/Linux and
1192some weird, without doubt broken, stuff on OS X to monitor files. It can
1193fall back to blocking scans at regular intervals transparently on other
1194platforms, so it's about as portable as it gets.
1195
1196(I haven't used it myself, but I haven't heard anybody complaining about
1197it yet).
1198
1084=item L<AnyEvent::HTTP> 1199=item L<AnyEvent::DBI>
1085 1200
1086A simple-to-use HTTP library that is capable of making a lot of concurrent 1201Executes L<DBI> requests asynchronously in a proxy process for you,
1087HTTP requests. 1202notifying you in an event-based way when the operation is finished.
1088 1203
1089=item L<AnyEvent::HTTPD> 1204=item L<AnyEvent::HTTPD>
1090 1205
1091Provides a simple web application server framework. 1206A simple embedded webserver.
1092 1207
1093=item L<AnyEvent::FastPing> 1208=item L<AnyEvent::FastPing>
1094 1209
1095The fastest ping in the west. 1210The fastest ping in the west.
1096 1211
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> 1212=item L<Coro>
1140 1213
1141Has special support for AnyEvent via L<Coro::AnyEvent>. 1214Has special support for AnyEvent via L<Coro::AnyEvent>, which allows you
1215to simply invert the flow control - don't call us, we will call you:
1216
1217 async {
1218 Coro::AnyEvent::sleep 5; # creates a 5s timer and waits for it
1219 print "5 seconds later!\n";
1220
1221 Coro::AnyEvent::readable *STDIN; # uses an I/O watcher
1222 my $line = <STDIN>; # works for ttys
1223
1224 AnyEvent::HTTP::http_get "url", Coro::rouse_cb;
1225 my ($body, $hdr) = Coro::rouse_wait;
1226 };
1142 1227
1143=back 1228=back
1144 1229
1145=cut 1230=cut
1146 1231
1147package AnyEvent; 1232package AnyEvent;
1148 1233
1149# basically a tuned-down version of common::sense 1234# basically a tuned-down version of common::sense
1150sub common_sense { 1235sub common_sense {
1151 # from common:.sense 1.0 1236 # from common:.sense 3.5
1237 local $^W;
1152 ${^WARNING_BITS} = "\xfc\x3f\x33\x00\x0f\xf3\xcf\xc0\xf3\xfc\x33\x00"; 1238 ${^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) 1239 # use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl)
1154 $^H |= 0x00000600; 1240 $^H |= 0x00000600;
1155} 1241}
1156 1242
1157BEGIN { AnyEvent::common_sense } 1243BEGIN { AnyEvent::common_sense }
1158 1244
1159use Carp (); 1245use Carp ();
1160 1246
1161our $VERSION = '5.24'; 1247our $VERSION = '7.04';
1162our $MODEL; 1248our $MODEL;
1163
1164our $AUTOLOAD;
1165our @ISA; 1249our @ISA;
1166
1167our @REGISTRY; 1250our @REGISTRY;
1168
1169our $VERBOSE; 1251our $VERBOSE;
1252our %PROTOCOL; # (ipv4|ipv6) => (1|2), higher numbers are preferred
1253our $MAX_SIGNAL_LATENCY = $ENV{PERL_ANYEVENT_MAX_SIGNAL_LATENCY} || 10; # executes after the BEGIN block below (tainting!)
1170 1254
1171BEGIN { 1255BEGIN {
1172 eval "sub CYGWIN(){" . (($^O =~ /cygwin/i) *1) . "}"; 1256 require "AnyEvent/constants.pl";
1173 eval "sub WIN32 (){" . (($^O =~ /mswin32/i)*1) . "}"; 1257
1174 eval "sub TAINT (){" . (${^TAINT} *1) . "}"; 1258 eval "sub TAINT (){" . (${^TAINT}*1) . "}";
1175 1259
1176 delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV} 1260 delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}
1177 if ${^TAINT}; 1261 if ${^TAINT};
1178 1262
1179 $VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1; 1263 $ENV{"PERL_ANYEVENT_$_"} = $ENV{"AE_$_"}
1264 for grep s/^AE_// && !exists $ENV{"PERL_ANYEVENT_$_"}, keys %ENV;
1180 1265
1181} 1266 @ENV{grep /^PERL_ANYEVENT_/, keys %ENV} = ()
1267 if ${^TAINT};
1182 1268
1183our $MAX_SIGNAL_LATENCY = 10; 1269 # $ENV{PERL_ANYEVENT_xxx} now valid
1184 1270
1185our %PROTOCOL; # (ipv4|ipv6) => (1|2), higher numbers are preferred 1271 $VERBOSE = length $ENV{PERL_ANYEVENT_VERBOSE} ? $ENV{PERL_ANYEVENT_VERBOSE}*1 : 4;
1186 1272
1187{
1188 my $idx; 1273 my $idx;
1189 $PROTOCOL{$_} = ++$idx 1274 $PROTOCOL{$_} = ++$idx
1190 for reverse split /\s*,\s*/, 1275 for reverse split /\s*,\s*/,
1191 $ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6"; 1276 $ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6";
1192} 1277}
1193 1278
1279our @post_detect;
1280
1281sub post_detect(&) {
1282 my ($cb) = @_;
1283
1284 push @post_detect, $cb;
1285
1286 defined wantarray
1287 ? bless \$cb, "AnyEvent::Util::postdetect"
1288 : ()
1289}
1290
1291sub AnyEvent::Util::postdetect::DESTROY {
1292 @post_detect = grep $_ != ${$_[0]}, @post_detect;
1293}
1294
1295our $POSTPONE_W;
1296our @POSTPONE;
1297
1298sub _postpone_exec {
1299 undef $POSTPONE_W;
1300
1301 &{ shift @POSTPONE }
1302 while @POSTPONE;
1303}
1304
1305sub postpone(&) {
1306 push @POSTPONE, shift;
1307
1308 $POSTPONE_W ||= AE::timer (0, 0, \&_postpone_exec);
1309
1310 ()
1311}
1312
1313sub log($$;@) {
1314 # only load the big bloated module when we actually are about to log something
1315 if ($_[0] <= ($VERBOSE || 1)) { # also catches non-numeric levels(!) and fatal
1316 local ($!, $@);
1317 require AnyEvent::Log; # among other things, sets $VERBOSE to 9
1318 # AnyEvent::Log overwrites this function
1319 goto &log;
1320 }
1321
1322 0 # not logged
1323}
1324
1325sub _logger($;$) {
1326 my ($level, $renabled) = @_;
1327
1328 $$renabled = $level <= $VERBOSE;
1329
1330 my $logger = [(caller)[0], $level, $renabled];
1331
1332 $AnyEvent::Log::LOGGER{$logger+0} = $logger;
1333
1334# return unless defined wantarray;
1335#
1336# require AnyEvent::Util;
1337# my $guard = AnyEvent::Util::guard (sub {
1338# # "clean up"
1339# delete $LOGGER{$logger+0};
1340# });
1341#
1342# sub {
1343# return 0 unless $$renabled;
1344#
1345# $guard if 0; # keep guard alive, but don't cause runtime overhead
1346# require AnyEvent::Log unless $AnyEvent::Log::VERSION;
1347# package AnyEvent::Log;
1348# _log ($logger->[0], $level, @_) # logger->[0] has been converted at load time
1349# }
1350}
1351
1352if (length $ENV{PERL_ANYEVENT_LOG}) {
1353 require AnyEvent::Log; # AnyEvent::Log does the thing for us
1354}
1355
1194my @models = ( 1356our @models = (
1195 [EV:: => AnyEvent::Impl::EV:: , 1], 1357 [EV:: => AnyEvent::Impl::EV::],
1196 [AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl:: , 1], 1358 [AnyEvent::Loop:: => AnyEvent::Impl::Perl::],
1197 # everything below here will not (normally) be autoprobed 1359 # everything below here will not (normally) be autoprobed
1198 # as the pureperl backend should work everywhere 1360 # as the pure perl backend should work everywhere
1199 # and is usually faster 1361 # and is usually faster
1362 [Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package, so msut be near the top
1200 [Event:: => AnyEvent::Impl::Event::, 1], 1363 [Event:: => AnyEvent::Impl::Event::], # slow, stable
1201 [Glib:: => AnyEvent::Impl::Glib:: , 1], # becomes extremely slow with many watchers 1364 [Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers
1365 # everything below here should not be autoloaded
1202 [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy 1366 [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 1367 [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
1205 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program 1368 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program
1206 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza 1369 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
1207 [Wx:: => AnyEvent::Impl::POE::], 1370 [Wx:: => AnyEvent::Impl::POE::],
1208 [Prima:: => AnyEvent::Impl::POE::], 1371 [Prima:: => AnyEvent::Impl::POE::],
1209 # IO::Async is just too broken - we would need workarounds for its 1372 [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # a bitch to autodetect
1210 # byzantine signal and broken child handling, among others. 1373 [Cocoa::EventLoop:: => AnyEvent::Impl::Cocoa::],
1211 # IO::Async is rather hard to detect, as it doesn't have any 1374 [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); 1375);
1218 1376
1219our %method = map +($_ => 1), 1377our @isa_hook;
1378
1379sub _isa_set {
1380 my @pkg = ("AnyEvent", (map $_->[0], grep defined, @isa_hook), $MODEL);
1381
1382 @{"$pkg[$_-1]::ISA"} = $pkg[$_]
1383 for 1 .. $#pkg;
1384
1385 grep $_ && $_->[1], @isa_hook
1386 and AE::_reset ();
1387}
1388
1389# used for hooking AnyEvent::Strict and AnyEvent::Debug::Wrap into the class hierarchy
1390sub _isa_hook($$;$) {
1391 my ($i, $pkg, $reset_ae) = @_;
1392
1393 $isa_hook[$i] = $pkg ? [$pkg, $reset_ae] : undef;
1394
1395 _isa_set;
1396}
1397
1398# all autoloaded methods reserve the complete glob, not just the method slot.
1399# due to bugs in perls method cache implementation.
1220 qw(io timer time now now_update signal child idle condvar one_event DESTROY); 1400our @methods = qw(io timer time now now_update signal child idle condvar);
1221
1222our @post_detect;
1223
1224sub post_detect(&) {
1225 my ($cb) = @_;
1226
1227 if ($MODEL) {
1228 $cb->();
1229
1230 undef
1231 } else {
1232 push @post_detect, $cb;
1233
1234 defined wantarray
1235 ? bless \$cb, "AnyEvent::Util::postdetect"
1236 : ()
1237 }
1238}
1239
1240sub AnyEvent::Util::postdetect::DESTROY {
1241 @post_detect = grep $_ != ${$_[0]}, @post_detect;
1242}
1243 1401
1244sub detect() { 1402sub detect() {
1403 return $MODEL if $MODEL; # some programs keep references to detect
1404
1405 # IO::Async::Loop::AnyEvent is extremely evil, refuse to work with it
1406 # the author knows about the problems and what it does to AnyEvent as a whole
1407 # (and the ability of others to use AnyEvent), but simply wants to abuse AnyEvent
1408 # anyway.
1409 AnyEvent::log fatal => "IO::Async::Loop::AnyEvent detected - that module is broken by\n"
1410 . "design, abuses internals and breaks AnyEvent - will not continue."
1411 if exists $INC{"IO/Async/Loop/AnyEvent.pm"};
1412
1413 local $!; # for good measure
1414 local $SIG{__DIE__}; # we use eval
1415
1245 # free some memory 1416 # free some memory
1246 *detect = sub () { $MODEL }; 1417 *detect = sub () { $MODEL };
1418 # undef &func doesn't correctly update the method cache. grmbl.
1419 # so we delete the whole glob. grmbl.
1420 # otoh, perl doesn't let me undef an active usb, but it lets me free
1421 # a glob with an active sub. hrm. i hope it works, but perl is
1422 # usually buggy in this department. sigh.
1423 delete @{"AnyEvent::"}{@methods};
1424 undef @methods;
1247 1425
1248 local $!; # for good measure
1249 local $SIG{__DIE__};
1250
1251 if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) { 1426 if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z0-9:]+)$/) {
1252 my $model = "AnyEvent::Impl::$1"; 1427 my $model = $1;
1428 $model = "AnyEvent::Impl::$model" unless $model =~ s/::$//;
1253 if (eval "require $model") { 1429 if (eval "require $model") {
1430 AnyEvent::log 7 => "Loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.";
1254 $MODEL = $model; 1431 $MODEL = $model;
1255 warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2;
1256 } else { 1432 } else {
1257 warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE; 1433 AnyEvent::log 4 => "Unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@";
1258 } 1434 }
1259 } 1435 }
1260 1436
1261 # check for already loaded models 1437 # check for already loaded models
1262 unless ($MODEL) { 1438 unless ($MODEL) {
1263 for (@REGISTRY, @models) { 1439 for (@REGISTRY, @models) {
1264 my ($package, $model) = @$_; 1440 my ($package, $model) = @$_;
1265 if (${"$package\::VERSION"} > 0) { 1441 if (${"$package\::VERSION"} > 0) {
1266 if (eval "require $model") { 1442 if (eval "require $model") {
1443 AnyEvent::log 7 => "Autodetected model '$model', using it.";
1267 $MODEL = $model; 1444 $MODEL = $model;
1268 warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2; 1445 last;
1446 } else {
1447 AnyEvent::log 8 => "Detected event loop $package, but cannot load '$model', skipping: $@";
1448 }
1449 }
1450 }
1451
1452 unless ($MODEL) {
1453 # try to autoload a model
1454 for (@REGISTRY, @models) {
1455 my ($package, $model) = @$_;
1456 if (
1457 eval "require $package"
1458 and ${"$package\::VERSION"} > 0
1459 and eval "require $model"
1460 ) {
1461 AnyEvent::log 7 => "Autoloaded model '$model', using it.";
1462 $MODEL = $model;
1269 last; 1463 last;
1270 } 1464 }
1271 } 1465 }
1272 }
1273
1274 unless ($MODEL) {
1275 # try to autoload a model
1276 for (@REGISTRY, @models) {
1277 my ($package, $model, $autoload) = @$_;
1278 if (
1279 $autoload
1280 and eval "require $package"
1281 and ${"$package\::VERSION"} > 0
1282 and eval "require $model"
1283 ) {
1284 $MODEL = $model;
1285 warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2;
1286 last;
1287 }
1288 }
1289 1466
1290 $MODEL 1467 $MODEL
1291 or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.\n"; 1468 or AnyEvent::log fatal => "Backend autodetection failed - did you properly install AnyEvent?";
1292 } 1469 }
1293 } 1470 }
1294 1471
1295 @models = (); # free probe data 1472 # free memory only needed for probing
1473 undef @models;
1474 undef @REGISTRY;
1296 1475
1297 push @{"$MODEL\::ISA"}, "AnyEvent::Base"; 1476 push @{"$MODEL\::ISA"}, "AnyEvent::Base";
1298 unshift @ISA, $MODEL;
1299 1477
1300 require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT}; 1478 # now nuke some methods that are overridden by the backend.
1479 # SUPER usage is not allowed in these.
1480 for (qw(time signal child idle)) {
1481 undef &{"AnyEvent::Base::$_"}
1482 if defined &{"$MODEL\::$_"};
1483 }
1484
1485 _isa_set;
1486
1487 # we're officially open!
1488
1489 if ($ENV{PERL_ANYEVENT_STRICT}) {
1490 require AnyEvent::Strict;
1491 }
1492
1493 if ($ENV{PERL_ANYEVENT_DEBUG_WRAP}) {
1494 require AnyEvent::Debug;
1495 AnyEvent::Debug::wrap ($ENV{PERL_ANYEVENT_DEBUG_WRAP});
1496 }
1497
1498 if (length $ENV{PERL_ANYEVENT_DEBUG_SHELL}) {
1499 require AnyEvent::Socket;
1500 require AnyEvent::Debug;
1501
1502 my $shell = $ENV{PERL_ANYEVENT_DEBUG_SHELL};
1503 $shell =~ s/\$\$/$$/g;
1504
1505 my ($host, $service) = AnyEvent::Socket::parse_hostport ($shell);
1506 $AnyEvent::Debug::SHELL = AnyEvent::Debug::shell ($host, $service);
1507 }
1508
1509 # now the anyevent environment is set up as the user told us to, so
1510 # call the actual user code - post detects
1301 1511
1302 (shift @post_detect)->() while @post_detect; 1512 (shift @post_detect)->() while @post_detect;
1513 undef @post_detect;
1514
1515 *post_detect = sub(&) {
1516 shift->();
1517
1518 undef
1519 };
1303 1520
1304 $MODEL 1521 $MODEL
1305} 1522}
1306 1523
1307sub AUTOLOAD { 1524for my $name (@methods) {
1308 (my $func = $AUTOLOAD) =~ s/.*://; 1525 *$name = sub {
1309
1310 $method{$func}
1311 or Carp::croak "$func: not a valid AnyEvent class method";
1312
1313 detect; 1526 detect;
1314 1527 # we use goto because
1315 my $class = shift; 1528 # a) it makes the thunk more transparent
1316 $class->$func (@_); 1529 # b) it allows us to delete the thunk later
1530 goto &{ UNIVERSAL::can AnyEvent => "SUPER::$name" }
1531 };
1317} 1532}
1318 1533
1319# utility function to dup a filehandle. this is used by many backends 1534# utility function to dup a filehandle. this is used by many backends
1320# to support binding more than one watcher per filehandle (they usually 1535# to support binding more than one watcher per filehandle (they usually
1321# allow only one watcher per fd, so we dup it to get a different one). 1536# allow only one watcher per fd, so we dup it to get a different one).
1335 1550
1336=head1 SIMPLIFIED AE API 1551=head1 SIMPLIFIED AE API
1337 1552
1338Starting with version 5.0, AnyEvent officially supports a second, much 1553Starting with version 5.0, AnyEvent officially supports a second, much
1339simpler, API that is designed to reduce the calling, typing and memory 1554simpler, API that is designed to reduce the calling, typing and memory
1340overhead. 1555overhead by using function call syntax and a fixed number of parameters.
1341 1556
1342See the L<AE> manpage for details. 1557See the L<AE> manpage for details.
1343 1558
1344=cut 1559=cut
1345 1560
1346package AE; 1561package AE;
1347 1562
1348our $VERSION = $AnyEvent::VERSION; 1563our $VERSION = $AnyEvent::VERSION;
1349 1564
1565sub _reset() {
1566 eval q{
1567 # fall back to the main API by default - backends and AnyEvent::Base
1568 # implementations can overwrite these.
1569
1350sub io($$$) { 1570 sub io($$$) {
1351 AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2]) 1571 AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])
1352} 1572 }
1353 1573
1354sub timer($$$) { 1574 sub timer($$$) {
1355 AnyEvent->timer (after => $_[0], interval => $_[1], cb => $_[2]) 1575 AnyEvent->timer (after => $_[0], interval => $_[1], cb => $_[2])
1356} 1576 }
1357 1577
1358sub signal($$) { 1578 sub signal($$) {
1359 AnyEvent->signal (signal => $_[0], cb => $_[1]) 1579 AnyEvent->signal (signal => $_[0], cb => $_[1])
1360} 1580 }
1361 1581
1362sub child($$) { 1582 sub child($$) {
1363 AnyEvent->child (pid => $_[0], cb => $_[1]) 1583 AnyEvent->child (pid => $_[0], cb => $_[1])
1364} 1584 }
1365 1585
1366sub idle($) { 1586 sub idle($) {
1367 AnyEvent->idle (cb => $_[0]) 1587 AnyEvent->idle (cb => $_[0]);
1368} 1588 }
1369 1589
1370sub cv(;&) { 1590 sub cv(;&) {
1371 AnyEvent->condvar (@_ ? (cb => $_[0]) : ()) 1591 AnyEvent->condvar (@_ ? (cb => $_[0]) : ())
1372} 1592 }
1373 1593
1374sub now() { 1594 sub now() {
1375 AnyEvent->now 1595 AnyEvent->now
1376} 1596 }
1377 1597
1378sub now_update() { 1598 sub now_update() {
1379 AnyEvent->now_update 1599 AnyEvent->now_update
1380} 1600 }
1381 1601
1382sub time() { 1602 sub time() {
1383 AnyEvent->time 1603 AnyEvent->time
1604 }
1605
1606 *postpone = \&AnyEvent::postpone;
1607 *log = \&AnyEvent::log;
1608 };
1609 die if $@;
1384} 1610}
1611
1612BEGIN { _reset }
1385 1613
1386package AnyEvent::Base; 1614package AnyEvent::Base;
1387 1615
1388# default implementations for many methods 1616# default implementations for many methods
1389 1617
1390sub _time() { 1618sub time {
1391 eval q{ # poor man's autoloading 1619 eval q{ # poor man's autoloading {}
1392 # probe for availability of Time::HiRes 1620 # probe for availability of Time::HiRes
1393 if (eval "use Time::HiRes (); Time::HiRes::time (); 1") { 1621 if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
1394 warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8; 1622 *time = sub { Time::HiRes::time () };
1395 *_time = \&Time::HiRes::time; 1623 *AE::time = \& Time::HiRes::time ;
1624 *now = \&time;
1625 AnyEvent::log 8 => "using Time::HiRes for sub-second timing accuracy.";
1396 # if (eval "use POSIX (); (POSIX::times())... 1626 # if (eval "use POSIX (); (POSIX::times())...
1397 } else { 1627 } else {
1628 *time = sub { CORE::time };
1629 *AE::time = sub (){ CORE::time };
1630 *now = \&time;
1398 warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE; 1631 AnyEvent::log 3 => "Using built-in time(), no sub-second resolution!";
1399 *_time = sub (){ time }; # epic fail
1400 } 1632 }
1401 }; 1633 };
1402 die if $@; 1634 die if $@;
1403 1635
1404 &_time 1636 &time
1405} 1637}
1406 1638
1407sub time { _time } 1639*now = \&time;
1408sub now { _time }
1409sub now_update { } 1640sub now_update { }
1410 1641
1642sub _poll {
1643 Carp::croak "$AnyEvent::MODEL does not support blocking waits. Caught";
1644}
1645
1411# default implementation for ->condvar 1646# default implementation for ->condvar
1647# in fact, the default should not be overwritten
1412 1648
1413sub condvar { 1649sub condvar {
1650 eval q{ # poor man's autoloading {}
1651 *condvar = sub {
1414 bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar" 1652 bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"
1653 };
1654
1655 *AE::cv = sub (;&) {
1656 bless { @_ ? (_ae_cb => shift) : () }, "AnyEvent::CondVar"
1657 };
1658 };
1659 die if $@;
1660
1661 &condvar
1415} 1662}
1416 1663
1417# default implementation for ->signal 1664# default implementation for ->signal
1418 1665
1419our $HAVE_ASYNC_INTERRUPT; 1666our $HAVE_ASYNC_INTERRUPT;
1449 undef $SIG_TW 1696 undef $SIG_TW
1450 unless --$SIG_COUNT; 1697 unless --$SIG_COUNT;
1451} 1698}
1452 1699
1453our $_sig_name_init; $_sig_name_init = sub { 1700our $_sig_name_init; $_sig_name_init = sub {
1454 eval q{ # poor man's autoloading 1701 eval q{ # poor man's autoloading {}
1455 undef $_sig_name_init; 1702 undef $_sig_name_init;
1456 1703
1457 if (_have_async_interrupt) { 1704 if (_have_async_interrupt) {
1458 *sig2num = \&Async::Interrupt::sig2num; 1705 *sig2num = \&Async::Interrupt::sig2num;
1459 *sig2name = \&Async::Interrupt::sig2name; 1706 *sig2name = \&Async::Interrupt::sig2name;
1483 1730
1484sub signal { 1731sub signal {
1485 eval q{ # poor man's autoloading {} 1732 eval q{ # poor man's autoloading {}
1486 # probe for availability of Async::Interrupt 1733 # probe for availability of Async::Interrupt
1487 if (_have_async_interrupt) { 1734 if (_have_async_interrupt) {
1488 warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8; 1735 AnyEvent::log 8 => "Using Async::Interrupt for race-free signal handling.";
1489 1736
1490 $SIGPIPE_R = new Async::Interrupt::EventPipe; 1737 $SIGPIPE_R = new Async::Interrupt::EventPipe;
1491 $SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec; 1738 $SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;
1492 1739
1493 } else { 1740 } else {
1494 warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8; 1741 AnyEvent::log 8 => "Using emulated perl signal handling with latency timer.";
1495
1496 require Fcntl;
1497 1742
1498 if (AnyEvent::WIN32) { 1743 if (AnyEvent::WIN32) {
1499 require AnyEvent::Util; 1744 require AnyEvent::Util;
1500 1745
1501 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe (); 1746 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
1502 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R; 1747 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R;
1503 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case 1748 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case
1504 } else { 1749 } else {
1505 pipe $SIGPIPE_R, $SIGPIPE_W; 1750 pipe $SIGPIPE_R, $SIGPIPE_W;
1506 fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R; 1751 fcntl $SIGPIPE_R, AnyEvent::F_SETFL, AnyEvent::O_NONBLOCK if $SIGPIPE_R;
1507 fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case 1752 fcntl $SIGPIPE_W, AnyEvent::F_SETFL, AnyEvent::O_NONBLOCK if $SIGPIPE_W; # just in case
1508 1753
1509 # not strictly required, as $^F is normally 2, but let's make sure... 1754 # not strictly required, as $^F is normally 2, but let's make sure...
1510 fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; 1755 fcntl $SIGPIPE_R, AnyEvent::F_SETFD, AnyEvent::FD_CLOEXEC;
1511 fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; 1756 fcntl $SIGPIPE_W, AnyEvent::F_SETFD, AnyEvent::FD_CLOEXEC;
1512 } 1757 }
1513 1758
1514 $SIGPIPE_R 1759 $SIGPIPE_R
1515 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n"; 1760 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1516 1761
1517 $SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec; 1762 $SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec;
1518 } 1763 }
1519 1764
1520 *signal = sub { 1765 *signal = $HAVE_ASYNC_INTERRUPT
1766 ? sub {
1521 my (undef, %arg) = @_; 1767 my (undef, %arg) = @_;
1522 1768
1523 my $signal = uc $arg{signal}
1524 or Carp::croak "required option 'signal' is missing";
1525
1526 if ($HAVE_ASYNC_INTERRUPT) {
1527 # async::interrupt 1769 # async::interrupt
1528
1529 $signal = sig2num $signal; 1770 my $signal = sig2num $arg{signal};
1530 $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; 1771 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1531 1772
1532 $SIG_ASY{$signal} ||= new Async::Interrupt 1773 $SIG_ASY{$signal} ||= new Async::Interrupt
1533 cb => sub { undef $SIG_EV{$signal} }, 1774 cb => sub { undef $SIG_EV{$signal} },
1534 signal => $signal, 1775 signal => $signal,
1535 pipe => [$SIGPIPE_R->filenos], 1776 pipe => [$SIGPIPE_R->filenos],
1536 pipe_autodrain => 0, 1777 pipe_autodrain => 0,
1537 ; 1778 ;
1538 1779
1539 } else { 1780 bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1781 }
1782 : sub {
1783 my (undef, %arg) = @_;
1784
1540 # pure perl 1785 # pure perl
1541
1542 # AE::Util has been loaded in signal
1543 $signal = sig2name $signal; 1786 my $signal = sig2name $arg{signal};
1544 $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; 1787 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1545 1788
1546 $SIG{$signal} ||= sub { 1789 $SIG{$signal} ||= sub {
1547 local $!; 1790 local $!;
1548 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV; 1791 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
1549 undef $SIG_EV{$signal}; 1792 undef $SIG_EV{$signal};
1550 }; 1793 };
1551 1794
1552 # can't do signal processing without introducing races in pure perl, 1795 # can't do signal processing without introducing races in pure perl,
1553 # so limit the signal latency. 1796 # so limit the signal latency.
1554 _sig_add; 1797 _sig_add;
1555 }
1556 1798
1557 bless [$signal, $arg{cb}], "AnyEvent::Base::signal" 1799 bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1800 }
1558 }; 1801 ;
1559 1802
1560 *AnyEvent::Base::signal::DESTROY = sub { 1803 *AnyEvent::Base::signal::DESTROY = sub {
1561 my ($signal, $cb) = @{$_[0]}; 1804 my ($signal, $cb) = @{$_[0]};
1562 1805
1563 _sig_del; 1806 _sig_del;
1579 : sysread $SIGPIPE_R, (my $dummy), 9; 1822 : sysread $SIGPIPE_R, (my $dummy), 9;
1580 1823
1581 while (%SIG_EV) { 1824 while (%SIG_EV) {
1582 for (keys %SIG_EV) { 1825 for (keys %SIG_EV) {
1583 delete $SIG_EV{$_}; 1826 delete $SIG_EV{$_};
1584 $_->() for values %{ $SIG_CB{$_} || {} }; 1827 &$_ for values %{ $SIG_CB{$_} || {} };
1585 } 1828 }
1586 } 1829 }
1587 }; 1830 };
1588 }; 1831 };
1589 die if $@; 1832 die if $@;
1594# default implementation for ->child 1837# default implementation for ->child
1595 1838
1596our %PID_CB; 1839our %PID_CB;
1597our $CHLD_W; 1840our $CHLD_W;
1598our $CHLD_DELAY_W; 1841our $CHLD_DELAY_W;
1599our $WNOHANG;
1600 1842
1601# used by many Impl's 1843# used by many Impl's
1602sub _emit_childstatus($$) { 1844sub _emit_childstatus($$) {
1603 my (undef, $rpid, $rstatus) = @_; 1845 my (undef, $rpid, $rstatus) = @_;
1604 1846
1611 eval q{ # poor man's autoloading {} 1853 eval q{ # poor man's autoloading {}
1612 *_sigchld = sub { 1854 *_sigchld = sub {
1613 my $pid; 1855 my $pid;
1614 1856
1615 AnyEvent->_emit_childstatus ($pid, $?) 1857 AnyEvent->_emit_childstatus ($pid, $?)
1616 while ($pid = waitpid -1, $WNOHANG) > 0; 1858 while ($pid = waitpid -1, WNOHANG) > 0;
1617 }; 1859 };
1618 1860
1619 *child = sub { 1861 *child = sub {
1620 my (undef, %arg) = @_; 1862 my (undef, %arg) = @_;
1621 1863
1622 defined (my $pid = $arg{pid} + 0) 1864 my $pid = $arg{pid};
1623 or Carp::croak "required option 'pid' is missing"; 1865 my $cb = $arg{cb};
1624 1866
1625 $PID_CB{$pid}{$arg{cb}} = $arg{cb}; 1867 $PID_CB{$pid}{$cb+0} = $cb;
1626
1627 # WNOHANG is almost cetrainly 1 everywhere
1628 $WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/
1629 ? 1
1630 : eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1;
1631 1868
1632 unless ($CHLD_W) { 1869 unless ($CHLD_W) {
1633 $CHLD_W = AE::signal CHLD => \&_sigchld; 1870 $CHLD_W = AE::signal CHLD => \&_sigchld;
1634 # child could be a zombie already, so make at least one round 1871 # child could be a zombie already, so make at least one round
1635 &_sigchld; 1872 &_sigchld;
1636 } 1873 }
1637 1874
1638 bless [$pid, $arg{cb}], "AnyEvent::Base::child" 1875 bless [$pid, $cb+0], "AnyEvent::Base::child"
1639 }; 1876 };
1640 1877
1641 *AnyEvent::Base::child::DESTROY = sub { 1878 *AnyEvent::Base::child::DESTROY = sub {
1642 my ($pid, $cb) = @{$_[0]}; 1879 my ($pid, $icb) = @{$_[0]};
1643 1880
1644 delete $PID_CB{$pid}{$cb}; 1881 delete $PID_CB{$pid}{$icb};
1645 delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} }; 1882 delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };
1646 1883
1647 undef $CHLD_W unless keys %PID_CB; 1884 undef $CHLD_W unless keys %PID_CB;
1648 }; 1885 };
1649 }; 1886 };
1662 1899
1663 my ($cb, $w, $rcb) = $arg{cb}; 1900 my ($cb, $w, $rcb) = $arg{cb};
1664 1901
1665 $rcb = sub { 1902 $rcb = sub {
1666 if ($cb) { 1903 if ($cb) {
1667 $w = _time; 1904 $w = AE::time;
1668 &$cb; 1905 &$cb;
1669 $w = _time - $w; 1906 $w = AE::time - $w;
1670 1907
1671 # never use more then 50% of the time for the idle watcher, 1908 # never use more then 50% of the time for the idle watcher,
1672 # within some limits 1909 # within some limits
1673 $w = 0.0001 if $w < 0.0001; 1910 $w = 0.0001 if $w < 0.0001;
1674 $w = 5 if $w > 5; 1911 $w = 5 if $w > 5;
1697 1934
1698package AnyEvent::CondVar; 1935package AnyEvent::CondVar;
1699 1936
1700our @ISA = AnyEvent::CondVar::Base::; 1937our @ISA = AnyEvent::CondVar::Base::;
1701 1938
1939# only to be used for subclassing
1940sub new {
1941 my $class = shift;
1942 bless AnyEvent->condvar (@_), $class
1943}
1944
1702package AnyEvent::CondVar::Base; 1945package AnyEvent::CondVar::Base;
1703 1946
1704#use overload 1947#use overload
1705# '&{}' => sub { my $self = shift; sub { $self->send (@_) } }, 1948# '&{}' => sub { my $self = shift; sub { $self->send (@_) } },
1706# fallback => 1; 1949# fallback => 1;
1715 1958
1716sub _send { 1959sub _send {
1717 # nop 1960 # nop
1718} 1961}
1719 1962
1963sub _wait {
1964 AnyEvent->_poll until $_[0]{_ae_sent};
1965}
1966
1720sub send { 1967sub send {
1721 my $cv = shift; 1968 my $cv = shift;
1722 $cv->{_ae_sent} = [@_]; 1969 $cv->{_ae_sent} = [@_];
1723 (delete $cv->{_ae_cb})->($cv) if $cv->{_ae_cb}; 1970 (delete $cv->{_ae_cb})->($cv) if $cv->{_ae_cb};
1724 $cv->_send; 1971 $cv->_send;
1731 1978
1732sub ready { 1979sub ready {
1733 $_[0]{_ae_sent} 1980 $_[0]{_ae_sent}
1734} 1981}
1735 1982
1736sub _wait {
1737 $WAITING
1738 and !$_[0]{_ae_sent}
1739 and Carp::croak "AnyEvent::CondVar: recursive blocking wait detected";
1740
1741 local $WAITING = 1;
1742 AnyEvent->one_event while !$_[0]{_ae_sent};
1743}
1744
1745sub recv { 1983sub recv {
1984 unless ($_[0]{_ae_sent}) {
1985 $WAITING
1986 and Carp::croak "AnyEvent::CondVar: recursive blocking wait attempted";
1987
1988 local $WAITING = 1;
1746 $_[0]->_wait; 1989 $_[0]->_wait;
1990 }
1747 1991
1748 Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak}; 1992 $_[0]{_ae_croak}
1749 wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0] 1993 and Carp::croak $_[0]{_ae_croak};
1994
1995 wantarray
1996 ? @{ $_[0]{_ae_sent} }
1997 : $_[0]{_ae_sent}[0]
1750} 1998}
1751 1999
1752sub cb { 2000sub cb {
1753 my $cv = shift; 2001 my $cv = shift;
1754 2002
1770 &{ $_[0]{_ae_end_cb} || sub { $_[0]->send } }; 2018 &{ $_[0]{_ae_end_cb} || sub { $_[0]->send } };
1771} 2019}
1772 2020
1773# undocumented/compatibility with pre-3.4 2021# undocumented/compatibility with pre-3.4
1774*broadcast = \&send; 2022*broadcast = \&send;
1775*wait = \&_wait; 2023*wait = \&recv;
1776 2024
1777=head1 ERROR AND EXCEPTION HANDLING 2025=head1 ERROR AND EXCEPTION HANDLING
1778 2026
1779In general, AnyEvent does not do any error handling - it relies on the 2027In general, AnyEvent does not do any error handling - it relies on the
1780caller to do that if required. The L<AnyEvent::Strict> module (see also 2028caller to do that if required. The L<AnyEvent::Strict> module (see also
1792$Event/EV::DIED->() >>, L<Glib> uses C<< install_exception_handler >> and 2040$Event/EV::DIED->() >>, L<Glib> uses C<< install_exception_handler >> and
1793so on. 2041so on.
1794 2042
1795=head1 ENVIRONMENT VARIABLES 2043=head1 ENVIRONMENT VARIABLES
1796 2044
1797The following environment variables are used by this module or its 2045AnyEvent supports a number of environment variables that tune the
1798submodules. 2046runtime behaviour. They are usually evaluated when AnyEvent is
2047loaded, initialised, or a submodule that uses them is loaded. Many of
2048them also cause AnyEvent to load additional modules - for example,
2049C<PERL_ANYEVENT_DEBUG_WRAP> causes the L<AnyEvent::Debug> module to be
2050loaded.
1799 2051
1800Note that AnyEvent will remove I<all> environment variables starting with 2052All the environment variables documented here start with
1801C<PERL_ANYEVENT_> from C<%ENV> when it is loaded while taint mode is 2053C<PERL_ANYEVENT_>, which is what AnyEvent considers its own
1802enabled. 2054namespace. Other modules are encouraged (but by no means required) to use
2055C<PERL_ANYEVENT_SUBMODULE> if they have registered the AnyEvent::Submodule
2056namespace on CPAN, for any submodule. For example, L<AnyEvent::HTTP> could
2057be expected to use C<PERL_ANYEVENT_HTTP_PROXY> (it should not access env
2058variables starting with C<AE_>, see below).
2059
2060All variables can also be set via the C<AE_> prefix, that is, instead
2061of setting C<PERL_ANYEVENT_VERBOSE> you can also set C<AE_VERBOSE>. In
2062case there is a clash btween anyevent and another program that uses
2063C<AE_something> you can set the corresponding C<PERL_ANYEVENT_something>
2064variable to the empty string, as those variables take precedence.
2065
2066When AnyEvent is first loaded, it copies all C<AE_xxx> env variables
2067to their C<PERL_ANYEVENT_xxx> counterpart unless that variable already
2068exists. If taint mode is on, then AnyEvent will remove I<all> environment
2069variables starting with C<PERL_ANYEVENT_> from C<%ENV> (or replace them
2070with C<undef> or the empty string, if the corresaponding C<AE_> variable
2071is set).
2072
2073The exact algorithm is currently:
2074
2075 1. if taint mode enabled, delete all PERL_ANYEVENT_xyz variables from %ENV
2076 2. copy over AE_xyz to PERL_ANYEVENT_xyz unless the latter alraedy exists
2077 3. if taint mode enabled, set all PERL_ANYEVENT_xyz variables to undef.
2078
2079This ensures that child processes will not see the C<AE_> variables.
2080
2081The following environment variables are currently known to AnyEvent:
1803 2082
1804=over 4 2083=over 4
1805 2084
1806=item C<PERL_ANYEVENT_VERBOSE> 2085=item C<PERL_ANYEVENT_VERBOSE>
1807 2086
1808By default, AnyEvent will be completely silent except in fatal 2087By default, AnyEvent will log messages with loglevel C<4> (C<error>) or
1809conditions. You can set this environment variable to make AnyEvent more 2088higher (see L<AnyEvent::Log>). You can set this environment variable to a
1810talkative. 2089numerical loglevel to make AnyEvent more (or less) talkative.
1811 2090
2091If you want to do more than just set the global logging level
2092you should have a look at C<PERL_ANYEVENT_LOG>, which allows much more
2093complex specifications.
2094
2095When set to C<0> (C<off>), then no messages whatsoever will be logged with
2096everything else at defaults.
2097
1812When set to C<1> or higher, causes AnyEvent to warn about unexpected 2098When set to C<5> or higher (C<warn>), AnyEvent warns about unexpected
1813conditions, such as not being able to load the event model specified by 2099conditions, such as not being able to load the event model specified by
1814C<PERL_ANYEVENT_MODEL>. 2100C<PERL_ANYEVENT_MODEL>, or a guard callback throwing an exception - this
2101is the minimum recommended level for use during development.
1815 2102
1816When set to C<2> or higher, cause AnyEvent to report to STDERR which event 2103When set to C<7> or higher (info), AnyEvent reports which event model it
1817model it chooses. 2104chooses.
1818 2105
1819When set to C<8> or higher, then AnyEvent will report extra information on 2106When set to C<8> or higher (debug), then AnyEvent will report extra
1820which optional modules it loads and how it implements certain features. 2107information on which optional modules it loads and how it implements
2108certain features.
2109
2110=item C<PERL_ANYEVENT_LOG>
2111
2112Accepts rather complex logging specifications. For example, you could log
2113all C<debug> messages of some module to stderr, warnings and above to
2114stderr, and errors and above to syslog, with:
2115
2116 PERL_ANYEVENT_LOG=Some::Module=debug,+log:filter=warn,+%syslog:%syslog=error,syslog
2117
2118For the rather extensive details, see L<AnyEvent::Log>.
2119
2120This variable is evaluated when AnyEvent (or L<AnyEvent::Log>) is loaded,
2121so will take effect even before AnyEvent has initialised itself.
2122
2123Note that specifying this environment variable causes the L<AnyEvent::Log>
2124module to be loaded, while C<PERL_ANYEVENT_VERBOSE> does not, so only
2125using the latter saves a few hundred kB of memory unless a module
2126explicitly needs the extra features of AnyEvent::Log.
1821 2127
1822=item C<PERL_ANYEVENT_STRICT> 2128=item C<PERL_ANYEVENT_STRICT>
1823 2129
1824AnyEvent does not do much argument checking by default, as thorough 2130AnyEvent does not do much argument checking by default, as thorough
1825argument checking is very costly. Setting this variable to a true value 2131argument checking is very costly. Setting this variable to a true value
1827check the arguments passed to most method calls. If it finds any problems, 2133check the arguments passed to most method calls. If it finds any problems,
1828it will croak. 2134it will croak.
1829 2135
1830In other words, enables "strict" mode. 2136In other words, enables "strict" mode.
1831 2137
1832Unlike C<use strict> (or it's modern cousin, C<< use L<common::sense> 2138Unlike C<use strict> (or its modern cousin, C<< use L<common::sense>
1833>>, it is definitely recommended to keep it off in production. Keeping 2139>>, it is definitely recommended to keep it off in production. Keeping
1834C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs 2140C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs
1835can be very useful, however. 2141can be very useful, however.
1836 2142
2143=item C<PERL_ANYEVENT_DEBUG_SHELL>
2144
2145If this env variable is nonempty, then its contents will be interpreted by
2146C<AnyEvent::Socket::parse_hostport> and C<AnyEvent::Debug::shell> (after
2147replacing every occurance of C<$$> by the process pid). The shell object
2148is saved in C<$AnyEvent::Debug::SHELL>.
2149
2150This happens when the first watcher is created.
2151
2152For example, to bind a debug shell on a unix domain socket in
2153F<< /tmp/debug<pid>.sock >>, you could use this:
2154
2155 PERL_ANYEVENT_DEBUG_SHELL=/tmp/debug\$\$.sock perlprog
2156 # connect with e.g.: socat readline /tmp/debug123.sock
2157
2158Or to bind to tcp port 4545 on localhost:
2159
2160 PERL_ANYEVENT_DEBUG_SHELL=127.0.0.1:4545 perlprog
2161 # connect with e.g.: telnet localhost 4545
2162
2163Note that creating sockets in F</tmp> or on localhost is very unsafe on
2164multiuser systems.
2165
2166=item C<PERL_ANYEVENT_DEBUG_WRAP>
2167
2168Can be set to C<0>, C<1> or C<2> and enables wrapping of all watchers for
2169debugging purposes. See C<AnyEvent::Debug::wrap> for details.
2170
1837=item C<PERL_ANYEVENT_MODEL> 2171=item C<PERL_ANYEVENT_MODEL>
1838 2172
1839This can be used to specify the event model to be used by AnyEvent, before 2173This can be used to specify the event model to be used by AnyEvent, before
1840auto detection and -probing kicks in. It must be a string consisting 2174auto detection and -probing kicks in.
1841entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended 2175
2176It normally is a string consisting entirely of ASCII letters (e.g. C<EV>
2177or C<IOAsync>). The string C<AnyEvent::Impl::> gets prepended and the
1842and the resulting module name is loaded and if the load was successful, 2178resulting module name is loaded and - if the load was successful - used as
1843used as event model. If it fails to load AnyEvent will proceed with 2179event model backend. If it fails to load then AnyEvent will proceed with
1844auto detection and -probing. 2180auto detection and -probing.
1845 2181
1846This functionality might change in future versions. 2182If the string ends with C<::> instead (e.g. C<AnyEvent::Impl::EV::>) then
2183nothing gets prepended and the module name is used as-is (hint: C<::> at
2184the end of a string designates a module name and quotes it appropriately).
1847 2185
1848For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you 2186For example, to force the pure perl model (L<AnyEvent::Loop::Perl>) you
1849could start your program like this: 2187could start your program like this:
1850 2188
1851 PERL_ANYEVENT_MODEL=Perl perl ... 2189 PERL_ANYEVENT_MODEL=Perl perl ...
2190
2191=item C<PERL_ANYEVENT_IO_MODEL>
2192
2193The current file I/O model - see L<AnyEvent::IO> for more info.
2194
2195At the moment, only C<Perl> (small, pure-perl, synchronous) and
2196C<IOAIO> (truly asynchronous) are supported. The default is C<IOAIO> if
2197L<AnyEvent::AIO> can be loaded, otherwise it is C<Perl>.
1852 2198
1853=item C<PERL_ANYEVENT_PROTOCOLS> 2199=item C<PERL_ANYEVENT_PROTOCOLS>
1854 2200
1855Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences 2201Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences
1856for IPv4 or IPv6. The default is unspecified (and might change, or be the result 2202for IPv4 or IPv6. The default is unspecified (and might change, or be the result
1869but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4> 2215but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4>
1870- only support IPv4, never try to resolve or contact IPv6 2216- only support IPv4, never try to resolve or contact IPv6
1871addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or 2217addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or
1872IPv6, but prefer IPv6 over IPv4. 2218IPv6, but prefer IPv6 over IPv4.
1873 2219
2220=item C<PERL_ANYEVENT_HOSTS>
2221
2222This variable, if specified, overrides the F</etc/hosts> file used by
2223L<AnyEvent::Socket>C<::resolve_sockaddr>, i.e. hosts aliases will be read
2224from that file instead.
2225
1874=item C<PERL_ANYEVENT_EDNS0> 2226=item C<PERL_ANYEVENT_EDNS0>
1875 2227
1876Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension 2228Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension for
1877for DNS. This extension is generally useful to reduce DNS traffic, but 2229DNS. This extension is generally useful to reduce DNS traffic, especially
1878some (broken) firewalls drop such DNS packets, which is why it is off by 2230when DNSSEC is involved, but some (broken) firewalls drop such DNS
1879default. 2231packets, which is why it is off by default.
1880 2232
1881Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce 2233Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce
1882EDNS0 in its DNS requests. 2234EDNS0 in its DNS requests.
1883 2235
1884=item C<PERL_ANYEVENT_MAX_FORKS> 2236=item C<PERL_ANYEVENT_MAX_FORKS>
1890 2242
1891The default value for the C<max_outstanding> parameter for the default DNS 2243The default value for the C<max_outstanding> parameter for the default DNS
1892resolver - this is the maximum number of parallel DNS requests that are 2244resolver - this is the maximum number of parallel DNS requests that are
1893sent to the DNS server. 2245sent to the DNS server.
1894 2246
2247=item C<PERL_ANYEVENT_MAX_SIGNAL_LATENCY>
2248
2249Perl has inherently racy signal handling (you can basically choose between
2250losing signals and memory corruption) - pure perl event loops (including
2251C<AnyEvent::Loop>, when C<Async::Interrupt> isn't available) therefore
2252have to poll regularly to avoid losing signals.
2253
2254Some event loops are racy, but don't poll regularly, and some event loops
2255are written in C but are still racy. For those event loops, AnyEvent
2256installs a timer that regularly wakes up the event loop.
2257
2258By default, the interval for this timer is C<10> seconds, but you can
2259override this delay with this environment variable (or by setting
2260the C<$AnyEvent::MAX_SIGNAL_LATENCY> variable before creating signal
2261watchers).
2262
2263Lower values increase CPU (and energy) usage, higher values can introduce
2264long delays when reaping children or waiting for signals.
2265
2266The L<AnyEvent::Async> module, if available, will be used to avoid this
2267polling (with most event loops).
2268
1895=item C<PERL_ANYEVENT_RESOLV_CONF> 2269=item C<PERL_ANYEVENT_RESOLV_CONF>
1896 2270
1897The file to use instead of F</etc/resolv.conf> (or OS-specific 2271The absolute path to a F<resolv.conf>-style file to use instead of
1898configuration) in the default resolver. When set to the empty string, no 2272F</etc/resolv.conf> (or the OS-specific configuration) in the default
1899default config will be used. 2273resolver, or the empty string to select the default configuration.
1900 2274
1901=item C<PERL_ANYEVENT_CA_FILE>, C<PERL_ANYEVENT_CA_PATH>. 2275=item C<PERL_ANYEVENT_CA_FILE>, C<PERL_ANYEVENT_CA_PATH>.
1902 2276
1903When neither C<ca_file> nor C<ca_path> was specified during 2277When neither C<ca_file> nor C<ca_path> was specified during
1904L<AnyEvent::TLS> context creation, and either of these environment 2278L<AnyEvent::TLS> context creation, and either of these environment
1905variables exist, they will be used to specify CA certificate locations 2279variables are nonempty, they will be used to specify CA certificate
1906instead of a system-dependent default. 2280locations instead of a system-dependent default.
1907 2281
1908=item C<PERL_ANYEVENT_AVOID_GUARD> and C<PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT> 2282=item C<PERL_ANYEVENT_AVOID_GUARD> and C<PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT>
1909 2283
1910When these are set to C<1>, then the respective modules are not 2284When these are set to C<1>, then the respective modules are not
1911loaded. Mostly good for testing AnyEvent itself. 2285loaded. Mostly good for testing AnyEvent itself.
2059 2433
2060The actual code goes further and collects all errors (C<die>s, exceptions) 2434The actual code goes further and collects all errors (C<die>s, exceptions)
2061that occurred during request processing. The C<result> method detects 2435that occurred during request processing. The C<result> method detects
2062whether an exception as thrown (it is stored inside the $txn object) 2436whether an exception as thrown (it is stored inside the $txn object)
2063and just throws the exception, which means connection errors and other 2437and just throws the exception, which means connection errors and other
2064problems get reported tot he code that tries to use the result, not in a 2438problems get reported to the code that tries to use the result, not in a
2065random callback. 2439random callback.
2066 2440
2067All of this enables the following usage styles: 2441All of this enables the following usage styles:
2068 2442
20691. Blocking: 24431. Blocking:
2243(even when used without AnyEvent), but most event loops have acceptable 2617(even when used without AnyEvent), but most event loops have acceptable
2244performance with or without AnyEvent. 2618performance with or without AnyEvent.
2245 2619
2246=item * The overhead AnyEvent adds is usually much smaller than the overhead of 2620=item * The overhead AnyEvent adds is usually much smaller than the overhead of
2247the actual event loop, only with extremely fast event loops such as EV 2621the actual event loop, only with extremely fast event loops such as EV
2248adds AnyEvent significant overhead. 2622does AnyEvent add significant overhead.
2249 2623
2250=item * You should avoid POE like the plague if you want performance or 2624=item * You should avoid POE like the plague if you want performance or
2251reasonable memory usage. 2625reasonable memory usage.
2252 2626
2253=back 2627=back
2483 unless defined $SIG{PIPE}; 2857 unless defined $SIG{PIPE};
2484 2858
2485=head1 RECOMMENDED/OPTIONAL MODULES 2859=head1 RECOMMENDED/OPTIONAL MODULES
2486 2860
2487One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and 2861One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and
2488it's built-in modules) are required to use it. 2862its built-in modules) are required to use it.
2489 2863
2490That does not mean that AnyEvent won't take advantage of some additional 2864That does not mean that AnyEvent won't take advantage of some additional
2491modules if they are installed. 2865modules if they are installed.
2492 2866
2493This section explains which additional modules will be used, and how they 2867This section explains which additional modules will be used, and how they
2526automatic timer adjustments even when no monotonic clock is available, 2900automatic timer adjustments even when no monotonic clock is available,
2527can take avdantage of advanced kernel interfaces such as C<epoll> and 2901can take avdantage of advanced kernel interfaces such as C<epoll> and
2528C<kqueue>, and is the fastest backend I<by far>. You can even embed 2902C<kqueue>, and is the fastest backend I<by far>. You can even embed
2529L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>). 2903L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>).
2530 2904
2905If you only use backends that rely on another event loop (e.g. C<Tk>),
2906then this module will do nothing for you.
2907
2531=item L<Guard> 2908=item L<Guard>
2532 2909
2533The guard module, when used, will be used to implement 2910The guard module, when used, will be used to implement
2534C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a 2911C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a
2535lot less memory), but otherwise doesn't affect guard operation much. It is 2912lot less memory), but otherwise doesn't affect guard operation much. It is
2536purely used for performance. 2913purely used for performance.
2537 2914
2538=item L<JSON> and L<JSON::XS> 2915=item L<JSON> and L<JSON::XS>
2539 2916
2540One of these modules is required when you want to read or write JSON data 2917One of these modules is required when you want to read or write JSON data
2541via L<AnyEvent::Handle>. It is also written in pure-perl, but can take 2918via L<AnyEvent::Handle>. L<JSON> is also written in pure-perl, but can take
2542advantage of the ultra-high-speed L<JSON::XS> module when it is installed. 2919advantage of the ultra-high-speed L<JSON::XS> module when it is installed.
2543
2544In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is
2545installed.
2546 2920
2547=item L<Net::SSLeay> 2921=item L<Net::SSLeay>
2548 2922
2549Implementing TLS/SSL in Perl is certainly interesting, but not very 2923Implementing TLS/SSL in Perl is certainly interesting, but not very
2550worthwhile: If this module is installed, then L<AnyEvent::Handle> (with 2924worthwhile: If this module is installed, then L<AnyEvent::Handle> (with
2551the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL. 2925the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL.
2552 2926
2553=item L<Time::HiRes> 2927=item L<Time::HiRes>
2554 2928
2555This module is part of perl since release 5.008. It will be used when the 2929This module is part of perl since release 5.008. It will be used when the
2556chosen event library does not come with a timing source on it's own. The 2930chosen event library does not come with a timing source of its own. The
2557pure-perl event loop (L<AnyEvent::Impl::Perl>) will additionally use it to 2931pure-perl event loop (L<AnyEvent::Loop>) will additionally load it to
2558try to use a monotonic clock for timing stability. 2932try to use a monotonic clock for timing stability.
2933
2934=item L<AnyEvent::AIO> (and L<IO::AIO>)
2935
2936The default implementation of L<AnyEvent::IO> is to do I/O synchronously,
2937stopping programs while they access the disk, which is fine for a lot of
2938programs.
2939
2940Installing AnyEvent::AIO (and its IO::AIO dependency) makes it switch to
2941a true asynchronous implementation, so event processing can continue even
2942while waiting for disk I/O.
2559 2943
2560=back 2944=back
2561 2945
2562 2946
2563=head1 FORK 2947=head1 FORK
2624pronounced). 3008pronounced).
2625 3009
2626 3010
2627=head1 SEE ALSO 3011=head1 SEE ALSO
2628 3012
2629Utility functions: L<AnyEvent::Util>. 3013Tutorial/Introduction: L<AnyEvent::Intro>.
2630 3014
2631Event modules: L<EV>, L<EV::Glib>, L<Glib::EV>, L<Event>, L<Glib::Event>, 3015FAQ: L<AnyEvent::FAQ>.
2632L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. 3016
3017Utility functions: L<AnyEvent::Util> (misc. grab-bag), L<AnyEvent::Log>
3018(simply logging).
3019
3020Development/Debugging: L<AnyEvent::Strict> (stricter checking),
3021L<AnyEvent::Debug> (interactive shell, watcher tracing).
3022
3023Supported event modules: L<AnyEvent::Loop>, L<EV>, L<EV::Glib>,
3024L<Glib::EV>, L<Event>, L<Glib::Event>, L<Glib>, L<Tk>, L<Event::Lib>,
3025L<Qt>, L<POE>, L<FLTK>.
2633 3026
2634Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>, 3027Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,
2635L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>, 3028L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,
2636L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>, 3029L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,
2637L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>. 3030L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>,
3031L<AnyEvent::Impl::FLTK>.
2638 3032
2639Non-blocking file handles, sockets, TCP clients and 3033Non-blocking handles, pipes, stream sockets, TCP clients and
2640servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>. 3034servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.
2641 3035
3036Asynchronous File I/O: L<AnyEvent::IO>.
3037
2642Asynchronous DNS: L<AnyEvent::DNS>. 3038Asynchronous DNS: L<AnyEvent::DNS>.
2643 3039
2644Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, 3040Thread support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>.
2645L<Coro::Event>,
2646 3041
2647Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::XMPP>, 3042Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::IRC>,
2648L<AnyEvent::HTTP>. 3043L<AnyEvent::HTTP>.
2649 3044
2650 3045
2651=head1 AUTHOR 3046=head1 AUTHOR
2652 3047
2653 Marc Lehmann <schmorp@schmorp.de> 3048 Marc Lehmann <schmorp@schmorp.de>
2654 http://home.schmorp.de/ 3049 http://anyevent.schmorp.de
2655 3050
2656=cut 3051=cut
2657 3052
26581 30531
2659 3054

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