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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
365When this is the case, you can call this method, which will update the 369When this is the case, you can call this method, which will update the
366event loop's idea of "current time". 370event loop's idea of "current time".
371
372A typical example would be a script in a web server (e.g. C<mod_perl>) -
373when mod_perl executes the script, then the event loop will have the wrong
374idea about the "current time" (being potentially far in the past, when the
375script ran the last time). In that case you should arrange a call to C<<
376AnyEvent->now_update >> each time the web server process wakes up again
377(e.g. at the start of your script, or in a handler).
367 378
368Note that updating the time I<might> cause some events to be handled. 379Note that updating the time I<might> cause some events to be handled.
369 380
370=back 381=back
371 382
396 407
397Example: exit on SIGINT 408Example: exit on SIGINT
398 409
399 my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 }); 410 my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
400 411
412=head3 Restart Behaviour
413
414While restart behaviour is up to the event loop implementation, most will
415not restart syscalls (that includes L<Async::Interrupt> and AnyEvent's
416pure perl implementation).
417
418=head3 Safe/Unsafe Signals
419
420Perl signals can be either "safe" (synchronous to opcode handling)
421or "unsafe" (asynchronous) - the former might delay signal delivery
422indefinitely, the latter might corrupt your memory.
423
424AnyEvent signal handlers are, in addition, synchronous to the event loop,
425i.e. they will not interrupt your running perl program but will only be
426called as part of the normal event handling (just like timer, I/O etc.
427callbacks, too).
428
401=head3 Signal Races, Delays and Workarounds 429=head3 Signal Races, Delays and Workarounds
402 430
403Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching 431Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support
404callbacks to signals in a generic way, which is a pity, as you cannot 432attaching callbacks to signals in a generic way, which is a pity,
405do race-free signal handling in perl, requiring C libraries for 433as you cannot do race-free signal handling in perl, requiring
406this. AnyEvent will try to do it's best, which means in some cases, 434C libraries for this. AnyEvent will try to do its best, which
407signals will be delayed. The maximum time a signal might be delayed is 435means in some cases, signals will be delayed. The maximum time
408specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This 436a signal might be delayed is 10 seconds by default, but can
409variable can be changed only before the first signal watcher is created, 437be overriden via C<$ENV{PERL_ANYEVENT_MAX_SIGNAL_LATENCY}> or
410and should be left alone otherwise. This variable determines how often 438C<$AnyEvent::MAX_SIGNAL_LATENCY> - see the Ö<ENVIRONMENT VARIABLES>
411AnyEvent polls for signals (in case a wake-up was missed). Higher values 439section for details.
412will cause fewer spurious wake-ups, which is better for power and CPU
413saving.
414 440
415All these problems can be avoided by installing the optional 441All these problems can be avoided by installing the optional
416L<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
417work 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>
418(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
419one-second latency). For those, you just have to suffer the delays. 445delays.
420 446
421=head2 CHILD PROCESS WATCHERS 447=head2 CHILD PROCESS WATCHERS
422 448
423 $w = AnyEvent->child (pid => <process id>, cb => <callback>); 449 $w = AnyEvent->child (pid => <process id>, cb => <callback>);
424 450
425You 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.
426 452
427The 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,
428using 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
429croak). The watcher will be triggered only when the child process has 455croak). The watcher will be triggered only when the child process has
430finished and an exit status is available, not on any trace events 456finished and an exit status is available, not on any trace events
431(stopped/continued). 457(stopped/continued).
432 458
454thing 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
455watcher before you C<fork> the child (alternatively, you can call 481watcher before you C<fork> the child (alternatively, you can call
456C<AnyEvent::detect>). 482C<AnyEvent::detect>).
457 483
458As 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
459emulated 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
460mentioned in the description of signal watchers apply. 486problems mentioned in the description of signal watchers apply.
461 487
462Example: fork a process and wait for it 488Example: fork a process and wait for it
463 489
464 my $done = AnyEvent->condvar; 490 my $done = AnyEvent->condvar;
465 491
479 505
480=head2 IDLE WATCHERS 506=head2 IDLE WATCHERS
481 507
482 $w = AnyEvent->idle (cb => <callback>); 508 $w = AnyEvent->idle (cb => <callback>);
483 509
484Sometimes there is a need to do something, but it is not so important 510This will repeatedly invoke the callback after the process becomes idle,
485to do it instantly, but only when there is nothing better to do. This 511until either the watcher is destroyed or new events have been detected.
486"nothing better to do" is usually defined to be "no other events need
487attention by the event loop".
488 512
489Idle watchers ideally get invoked when the event loop has nothing 513Idle watchers are useful when there is a need to do something, but it
490better to do, just before it would block the process to wait for new 514is not so important (or wise) to do it instantly. The callback will be
491events. Instead of blocking, the idle watcher is invoked. 515invoked only when there is "nothing better to do", which is usually
516defined as "all outstanding events have been handled and no new events
517have been detected". That means that idle watchers ideally get invoked
518when the event loop has just polled for new events but none have been
519detected. Instead of blocking to wait for more events, the idle watchers
520will be invoked.
492 521
493Most event loops unfortunately do not really support idle watchers (only 522Unfortunately, most event loops do not really support idle watchers (only
494EV, Event and Glib do it in a usable fashion) - for the rest, AnyEvent 523EV, Event and Glib do it in a usable fashion) - for the rest, AnyEvent
495will simply call the callback "from time to time". 524will simply call the callback "from time to time".
496 525
497Example: read lines from STDIN, but only process them when the 526Example: read lines from STDIN, but only process them when the
498program is otherwise idle: 527program is otherwise idle:
526will actively watch for new events and call your callbacks. 555will actively watch for new events and call your callbacks.
527 556
528AnyEvent is slightly different: it expects somebody else to run the event 557AnyEvent is slightly different: it expects somebody else to run the event
529loop 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).
530 559
531The instrument to do that is called a "condition variable", so called 560The tool to do that is called a "condition variable", so called because
532because they represent a condition that must become true. 561they represent a condition that must become true.
533 562
534Now 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.
535 564
536Condition variables can be created by calling the C<< AnyEvent->condvar 565Condition variables can be created by calling the C<< AnyEvent->condvar
537>> method, usually without arguments. The only argument pair allowed is 566>> method, usually without arguments. The only argument pair allowed is
542After creation, the condition variable is "false" until it becomes "true" 571After creation, the condition variable is "false" until it becomes "true"
543by 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
544were 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<<
545->send >> method). 574->send >> method).
546 575
547Condition variables are similar to callbacks, except that you can 576Since condition variables are the most complex part of the AnyEvent API, here are
548optionally wait for them. They can also be called merge points - points 577some different mental models of what they are - pick the ones you can connect to:
549in time where multiple outstanding events have been processed. And yet 578
550another way to call them is transactions - each condition variable can be 579=over 4
551used to represent a transaction, which finishes at some point and delivers 580
552a 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
553compute/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
554 599
555Condition variables are very useful to signal that something has finished, 600Condition variables are very useful to signal that something has finished,
556for example, if you write a module that does asynchronous http requests, 601for example, if you write a module that does asynchronous http requests,
557then a condition variable would be the ideal candidate to signal the 602then a condition variable would be the ideal candidate to signal the
558availability of results. The user can either act when the callback is 603availability of results. The user can either act when the callback is
571 616
572Condition variables are represented by hash refs in perl, and the keys 617Condition variables are represented by hash refs in perl, and the keys
573used 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
574easy (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
575AnyEvent). To subclass, use C<AnyEvent::CondVar> as base class and call 620AnyEvent). To subclass, use C<AnyEvent::CondVar> as base class and call
576it's C<new> method in your own C<new> method. 621its C<new> method in your own C<new> method.
577 622
578There are two "sides" to a condition variable - the "producer side" which 623There are two "sides" to a condition variable - the "producer side" which
579eventually calls C<< -> send >>, and the "consumer side", which waits 624eventually calls C<< -> send >>, and the "consumer side", which waits
580for the send to occur. 625for the send to occur.
581 626
582Example: wait for a timer. 627Example: wait for a timer.
583 628
584 # wait till the result is ready 629 # condition: "wait till the timer is fired"
585 my $result_ready = AnyEvent->condvar; 630 my $timer_fired = AnyEvent->condvar;
586 631
587 # do something such as adding a timer 632 # create the timer - we could wait for, say
588 # or socket watcher the calls $result_ready->send 633 # a handle becomign ready, or even an
589 # when the "result" is ready. 634 # AnyEvent::HTTP request to finish, but
590 # in this case, we simply use a timer: 635 # in this case, we simply use a timer:
591 my $w = AnyEvent->timer ( 636 my $w = AnyEvent->timer (
592 after => 1, 637 after => 1,
593 cb => sub { $result_ready->send }, 638 cb => sub { $timer_fired->send },
594 ); 639 );
595 640
596 # this "blocks" (while handling events) till the callback 641 # this "blocks" (while handling events) till the callback
597 # calls -<send 642 # calls ->send
598 $result_ready->recv; 643 $timer_fired->recv;
599 644
600Example: 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
601variables are also callable directly. 646variables are also callable directly.
602 647
603 my $done = AnyEvent->condvar; 648 my $done = AnyEvent->condvar;
646they 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
647C<send>. 692C<send>.
648 693
649=item $cv->croak ($error) 694=item $cv->croak ($error)
650 695
651Similar to send, but causes all call's to C<< ->recv >> to invoke 696Similar to send, but causes all calls to C<< ->recv >> to invoke
652C<Carp::croak> with the given error message/object/scalar. 697C<Carp::croak> with the given error message/object/scalar.
653 698
654This can be used to signal any errors to the condition variable 699This can be used to signal any errors to the condition variable
655user/consumer. Doing it this way instead of calling C<croak> directly 700user/consumer. Doing it this way instead of calling C<croak> directly
656delays the error detetcion, but has the overwhelmign advantage that it 701delays the error detection, but has the overwhelming advantage that it
657diagnoses 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
658deep in some event clalback without connection to the actual code causing 703deep in some event callback with no connection to the actual code causing
659the problem. 704the problem.
660 705
661=item $cv->begin ([group callback]) 706=item $cv->begin ([group callback])
662 707
663=item $cv->end 708=item $cv->end
701one 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
702sending. 747sending.
703 748
704The ping example mentioned above is slightly more complicated, as the 749The ping example mentioned above is slightly more complicated, as the
705there 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
706begung can potentially be zero: 751begun can potentially be zero:
707 752
708 my $cv = AnyEvent->condvar; 753 my $cv = AnyEvent->condvar;
709 754
710 my %result; 755 my %result;
711 $cv->begin (sub { shift->send (\%result) }); 756 $cv->begin (sub { shift->send (\%result) });
732to be called once the counter reaches C<0>, and second, it ensures that 777to be called once the counter reaches C<0>, and second, it ensures that
733C<send> is called even when C<no> hosts are being pinged (the loop 778C<send> is called even when C<no> hosts are being pinged (the loop
734doesn't execute once). 779doesn't execute once).
735 780
736This is the general pattern when you "fan out" into multiple (but 781This is the general pattern when you "fan out" into multiple (but
737potentially none) subrequests: use an outer C<begin>/C<end> pair to set 782potentially zero) subrequests: use an outer C<begin>/C<end> pair to set
738the callback and ensure C<end> is called at least once, and then, for each 783the callback and ensure C<end> is called at least once, and then, for each
739subrequest you start, call C<begin> and for each subrequest you finish, 784subrequest you start, call C<begin> and for each subrequest you finish,
740call C<end>. 785call C<end>.
741 786
742=back 787=back
749=over 4 794=over 4
750 795
751=item $cv->recv 796=item $cv->recv
752 797
753Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak 798Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak
754>> methods have been called on c<$cv>, while servicing other watchers 799>> methods have been called on C<$cv>, while servicing other watchers
755normally. 800normally.
756 801
757You can only wait once on a condition - additional calls are valid but 802You can only wait once on a condition - additional calls are valid but
758will return immediately. 803will return immediately.
759 804
776caller decide whether the call will block or not (for example, by coupling 821caller decide whether the call will block or not (for example, by coupling
777condition variables with some kind of request results and supporting 822condition variables with some kind of request results and supporting
778callbacks so the caller knows that getting the result will not block, 823callbacks so the caller knows that getting the result will not block,
779while still supporting blocking waits if the caller so desires). 824while still supporting blocking waits if the caller so desires).
780 825
781You can ensure that C<< -recv >> never blocks by setting a callback and 826You can ensure that C<< ->recv >> never blocks by setting a callback and
782only calling C<< ->recv >> from within that callback (or at a later 827only calling C<< ->recv >> from within that callback (or at a later
783time). This will work even when the event loop does not support blocking 828time). This will work even when the event loop does not support blocking
784waits otherwise. 829waits otherwise.
785 830
786=item $bool = $cv->ready 831=item $bool = $cv->ready
791=item $cb = $cv->cb ($cb->($cv)) 836=item $cb = $cv->cb ($cb->($cv))
792 837
793This is a mutator function that returns the callback set and optionally 838This is a mutator function that returns the callback set and optionally
794replaces it before doing so. 839replaces it before doing so.
795 840
796The callback will be called when the condition becomes (or already was) 841The callback will be called when the condition becomes "true", i.e. when
797"true", i.e. when C<send> or C<croak> are called (or were called), with 842C<send> or C<croak> are called, with the only argument being the
798the only argument being the condition variable itself. Calling C<recv> 843condition variable itself. If the condition is already true, the
844callback is called immediately when it is set. Calling C<recv> inside
799inside the callback or at any later time is guaranteed not to block. 845the callback or at any later time is guaranteed not to block.
800 846
801=back 847=back
802 848
803=head1 SUPPORTED EVENT LOOPS/BACKENDS 849=head1 SUPPORTED EVENT LOOPS/BACKENDS
804 850
812use. If EV is not installed, then AnyEvent will fall back to its own 858use. If EV is not installed, then AnyEvent will fall back to its own
813pure-perl implementation, which is available everywhere as it comes with 859pure-perl implementation, which is available everywhere as it comes with
814AnyEvent itself. 860AnyEvent itself.
815 861
816 AnyEvent::Impl::EV based on EV (interface to libev, best choice). 862 AnyEvent::Impl::EV based on EV (interface to libev, best choice).
817 AnyEvent::Impl::Perl pure-perl implementation, fast and portable. 863 AnyEvent::Impl::Perl pure-perl AnyEvent::Loop, fast and portable.
818 864
819=item Backends that are transparently being picked up when they are used. 865=item Backends that are transparently being picked up when they are used.
820 866
821These will be used when they are currently loaded when the first watcher 867These will be used if they are already loaded when the first watcher
822is created, in which case it is assumed that the application is using 868is created, in which case it is assumed that the application is using
823them. This means that AnyEvent will automatically pick the right backend 869them. This means that AnyEvent will automatically pick the right backend
824when the main program loads an event module before anything starts to 870when the main program loads an event module before anything starts to
825create watchers. Nothing special needs to be done by the main program. 871create watchers. Nothing special needs to be done by the main program.
826 872
828 AnyEvent::Impl::Glib based on Glib, slow but very stable. 874 AnyEvent::Impl::Glib based on Glib, slow but very stable.
829 AnyEvent::Impl::Tk based on Tk, very broken. 875 AnyEvent::Impl::Tk based on Tk, very broken.
830 AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. 876 AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
831 AnyEvent::Impl::POE based on POE, very slow, some limitations. 877 AnyEvent::Impl::POE based on POE, very slow, some limitations.
832 AnyEvent::Impl::Irssi used when running within irssi. 878 AnyEvent::Impl::Irssi used when running within irssi.
879 AnyEvent::Impl::IOAsync based on IO::Async.
880 AnyEvent::Impl::Cocoa based on Cocoa::EventLoop.
881 AnyEvent::Impl::FLTK based on FLTK (fltk 2 binding).
833 882
834=item Backends with special needs. 883=item Backends with special needs.
835 884
836Qt requires the Qt::Application to be instantiated first, but will 885Qt requires the Qt::Application to be instantiated first, but will
837otherwise be picked up automatically. As long as the main program 886otherwise be picked up automatically. As long as the main program
838instantiates the application before any AnyEvent watchers are created, 887instantiates the application before any AnyEvent watchers are created,
839everything should just work. 888everything should just work.
840 889
841 AnyEvent::Impl::Qt based on Qt. 890 AnyEvent::Impl::Qt based on Qt.
842 891
843Support for IO::Async can only be partial, as it is too broken and
844architecturally limited to even support the AnyEvent API. It also
845is the only event loop that needs the loop to be set explicitly, so
846it can only be used by a main program knowing about AnyEvent. See
847L<AnyEvent::Impl::Async> for the gory details.
848
849 AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed.
850
851=item Event loops that are indirectly supported via other backends. 892=item Event loops that are indirectly supported via other backends.
852 893
853Some event loops can be supported via other modules: 894Some event loops can be supported via other modules:
854 895
855There is no direct support for WxWidgets (L<Wx>) or L<Prima>. 896There is no direct support for WxWidgets (L<Wx>) or L<Prima>.
880Contains C<undef> until the first watcher is being created, before the 921Contains C<undef> until the first watcher is being created, before the
881backend has been autodetected. 922backend has been autodetected.
882 923
883Afterwards it contains the event model that is being used, which is the 924Afterwards it contains the event model that is being used, which is the
884name of the Perl class implementing the model. This class is usually one 925name of the Perl class implementing the model. This class is usually one
885of the C<AnyEvent::Impl:xxx> modules, but can be any other class in the 926of the C<AnyEvent::Impl::xxx> modules, but can be any other class in the
886case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it 927case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it
887will be C<urxvt::anyevent>). 928will be C<urxvt::anyevent>).
888 929
889=item AnyEvent::detect 930=item AnyEvent::detect
890 931
891Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model 932Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model
892if necessary. You should only call this function right before you would 933if necessary. You should only call this function right before you would
893have created an AnyEvent watcher anyway, that is, as late as possible at 934have created an AnyEvent watcher anyway, that is, as late as possible at
894runtime, and not e.g. while initialising of your module. 935runtime, and not e.g. during initialisation of your module.
936
937The effect of calling this function is as if a watcher had been created
938(specifically, actions that happen "when the first watcher is created"
939happen when calling detetc as well).
895 940
896If you need to do some initialisation before AnyEvent watchers are 941If you need to do some initialisation before AnyEvent watchers are
897created, use C<post_detect>. 942created, use C<post_detect>.
898 943
899=item $guard = AnyEvent::post_detect { BLOCK } 944=item $guard = AnyEvent::post_detect { BLOCK }
900 945
901Arranges for the code block to be executed as soon as the event model is 946Arranges for the code block to be executed as soon as the event model is
902autodetected (or immediately if this has already happened). 947autodetected (or immediately if that has already happened).
903 948
904The block will be executed I<after> the actual backend has been detected 949The block will be executed I<after> the actual backend has been detected
905(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been 950(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been
906created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do 951created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do
907other initialisations - see the sources of L<AnyEvent::Strict> or 952other initialisations - see the sources of L<AnyEvent::Strict> or
916that automatically removes the callback again when it is destroyed (or 961that automatically removes the callback again when it is destroyed (or
917C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for 962C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for
918a case where this is useful. 963a case where this is useful.
919 964
920Example: Create a watcher for the IO::AIO module and store it in 965Example: Create a watcher for the IO::AIO module and store it in
921C<$WATCHER>. Only do so after the event loop is initialised, though. 966C<$WATCHER>, but do so only do so after the event loop is initialised.
922 967
923 our WATCHER; 968 our WATCHER;
924 969
925 my $guard = AnyEvent::post_detect { 970 my $guard = AnyEvent::post_detect {
926 $WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb); 971 $WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb);
934 $WATCHER ||= $guard; 979 $WATCHER ||= $guard;
935 980
936=item @AnyEvent::post_detect 981=item @AnyEvent::post_detect
937 982
938If there are any code references in this array (you can C<push> to it 983If there are any code references in this array (you can C<push> to it
939before or after loading AnyEvent), then they will called directly after 984before or after loading AnyEvent), then they will be called directly
940the event loop has been chosen. 985after the event loop has been chosen.
941 986
942You should check C<$AnyEvent::MODEL> before adding to this array, though: 987You should check C<$AnyEvent::MODEL> before adding to this array, though:
943if it is defined then the event loop has already been detected, and the 988if it is defined then the event loop has already been detected, and the
944array will be ignored. 989array will be ignored.
945 990
946Best use C<AnyEvent::post_detect { BLOCK }> when your application allows 991Best use C<AnyEvent::post_detect { BLOCK }> when your application allows
947it,as it takes care of these details. 992it, as it takes care of these details.
948 993
949This variable is mainly useful for modules that can do something useful 994This variable is mainly useful for modules that can do something useful
950when AnyEvent is used and thus want to know when it is initialised, but do 995when AnyEvent is used and thus want to know when it is initialised, but do
951not need to even load it by default. This array provides the means to hook 996not need to even load it by default. This array provides the means to hook
952into AnyEvent passively, without loading it. 997into AnyEvent passively, without loading it.
953 998
999Example: To load Coro::AnyEvent whenever Coro and AnyEvent are used
1000together, you could put this into Coro (this is the actual code used by
1001Coro to accomplish this):
1002
1003 if (defined $AnyEvent::MODEL) {
1004 # AnyEvent already initialised, so load Coro::AnyEvent
1005 require Coro::AnyEvent;
1006 } else {
1007 # AnyEvent not yet initialised, so make sure to load Coro::AnyEvent
1008 # as soon as it is
1009 push @AnyEvent::post_detect, sub { require Coro::AnyEvent };
1010 }
1011
1012=item AnyEvent::postpone { BLOCK }
1013
1014Arranges for the block to be executed as soon as possible, but not before
1015the call itself returns. In practise, the block will be executed just
1016before the event loop polls for new events, or shortly afterwards.
1017
1018This function never returns anything (to make the C<return postpone { ...
1019}> idiom more useful.
1020
1021To understand the usefulness of this function, consider a function that
1022asynchronously does something for you and returns some transaction
1023object or guard to let you cancel the operation. For example,
1024C<AnyEvent::Socket::tcp_connect>:
1025
1026 # start a conenction attempt unless one is active
1027 $self->{connect_guard} ||= AnyEvent::Socket::tcp_connect "www.example.net", 80, sub {
1028 delete $self->{connect_guard};
1029 ...
1030 };
1031
1032Imagine that this function could instantly call the callback, for
1033example, because it detects an obvious error such as a negative port
1034number. Invoking the callback before the function returns causes problems
1035however: the callback will be called and will try to delete the guard
1036object. But since the function hasn't returned yet, there is nothing to
1037delete. When the function eventually returns it will assign the guard
1038object to C<< $self->{connect_guard} >>, where it will likely never be
1039deleted, so the program thinks it is still trying to connect.
1040
1041This is where C<AnyEvent::postpone> should be used. Instead of calling the
1042callback directly on error:
1043
1044 $cb->(undef), return # signal error to callback, BAD!
1045 if $some_error_condition;
1046
1047It should use C<postpone>:
1048
1049 AnyEvent::postpone { $cb->(undef) }, return # signal error to callback, later
1050 if $some_error_condition;
1051
1052=item AnyEvent::log $level, $msg[, @args]
1053
1054Log the given C<$msg> at the given C<$level>.
1055
1056If L<AnyEvent::Log> is not loaded then this function makes a simple test
1057to see whether the message will be logged. If the test succeeds it will
1058load AnyEvent::Log and call C<AnyEvent::Log::log> - consequently, look at
1059the L<AnyEvent::Log> documentation for details.
1060
1061If the test fails it will simply return. Right now this happens when a
1062numerical loglevel is used and it is larger than the level specified via
1063C<$ENV{PERL_ANYEVENT_VERBOSE}>.
1064
1065If you want to sprinkle loads of logging calls around your code, consider
1066creating a logger callback with the C<AnyEvent::Log::logger> function,
1067which can reduce typing, codesize and can reduce the logging overhead
1068enourmously.
1069
954=back 1070=back
955 1071
956=head1 WHAT TO DO IN A MODULE 1072=head1 WHAT TO DO IN A MODULE
957 1073
958As a module author, you should C<use AnyEvent> and call AnyEvent methods 1074As a module author, you should C<use AnyEvent> and call AnyEvent methods
968because it will stall the whole program, and the whole point of using 1084because it will stall the whole program, and the whole point of using
969events is to stay interactive. 1085events is to stay interactive.
970 1086
971It is fine, however, to call C<< ->recv >> when the user of your module 1087It is fine, however, to call C<< ->recv >> when the user of your module
972requests it (i.e. if you create a http request object ad have a method 1088requests it (i.e. if you create a http request object ad have a method
973called C<results> that returns the results, it should call C<< ->recv >> 1089called C<results> that returns the results, it may call C<< ->recv >>
974freely, as the user of your module knows what she is doing. always). 1090freely, as the user of your module knows what she is doing. Always).
975 1091
976=head1 WHAT TO DO IN THE MAIN PROGRAM 1092=head1 WHAT TO DO IN THE MAIN PROGRAM
977 1093
978There will always be a single main program - the only place that should 1094There will always be a single main program - the only place that should
979dictate which event model to use. 1095dictate which event model to use.
980 1096
981If it doesn't care, it can just "use AnyEvent" and use it itself, or not 1097If the program is not event-based, it need not do anything special, even
982do anything special (it does not need to be event-based) and let AnyEvent 1098when it depends on a module that uses an AnyEvent. If the program itself
983decide which implementation to chose if some module relies on it. 1099uses AnyEvent, but does not care which event loop is used, all it needs
1100to do is C<use AnyEvent>. In either case, AnyEvent will choose the best
1101available loop implementation.
984 1102
985If the main program relies on a specific event model - for example, in 1103If the main program relies on a specific event model - for example, in
986Gtk2 programs you have to rely on the Glib module - you should load the 1104Gtk2 programs you have to rely on the Glib module - you should load the
987event module before loading AnyEvent or any module that uses it: generally 1105event module before loading AnyEvent or any module that uses it: generally
988speaking, you should load it as early as possible. The reason is that 1106speaking, you should load it as early as possible. The reason is that
989modules might create watchers when they are loaded, and AnyEvent will 1107modules might create watchers when they are loaded, and AnyEvent will
990decide on the event model to use as soon as it creates watchers, and it 1108decide on the event model to use as soon as it creates watchers, and it
991might chose the wrong one unless you load the correct one yourself. 1109might choose the wrong one unless you load the correct one yourself.
992 1110
993You can chose to use a pure-perl implementation by loading the 1111You can chose to use a pure-perl implementation by loading the
994C<AnyEvent::Impl::Perl> module, which gives you similar behaviour 1112C<AnyEvent::Loop> module, which gives you similar behaviour
995everywhere, but letting AnyEvent chose the model is generally better. 1113everywhere, but letting AnyEvent chose the model is generally better.
996 1114
997=head2 MAINLOOP EMULATION 1115=head2 MAINLOOP EMULATION
998 1116
999Sometimes (often for short test scripts, or even standalone programs who 1117Sometimes (often for short test scripts, or even standalone programs who
1012 1130
1013 1131
1014=head1 OTHER MODULES 1132=head1 OTHER MODULES
1015 1133
1016The following is a non-exhaustive list of additional modules that use 1134The following is a non-exhaustive list of additional modules that use
1017AnyEvent as a client and can therefore be mixed easily with other AnyEvent 1135AnyEvent as a client and can therefore be mixed easily with other
1018modules and other event loops in the same program. Some of the modules 1136AnyEvent modules and other event loops in the same program. Some of the
1019come with AnyEvent, most are available via CPAN. 1137modules come as part of AnyEvent, the others are available via CPAN (see
1138L<http://search.cpan.org/search?m=module&q=anyevent%3A%3A*> for
1139a longer non-exhaustive list), and the list is heavily biased towards
1140modules of the AnyEvent author himself :)
1020 1141
1021=over 4 1142=over 4
1022 1143
1023=item L<AnyEvent::Util> 1144=item L<AnyEvent::Util>
1024 1145
1025Contains various utility functions that replace often-used but blocking 1146Contains various utility functions that replace often-used blocking
1026functions such as C<inet_aton> by event-/callback-based versions. 1147functions such as C<inet_aton> with event/callback-based versions.
1027 1148
1028=item L<AnyEvent::Socket> 1149=item L<AnyEvent::Socket>
1029 1150
1030Provides various utility functions for (internet protocol) sockets, 1151Provides various utility functions for (internet protocol) sockets,
1031addresses and name resolution. Also functions to create non-blocking tcp 1152addresses and name resolution. Also functions to create non-blocking tcp
1033 1154
1034=item L<AnyEvent::Handle> 1155=item L<AnyEvent::Handle>
1035 1156
1036Provide read and write buffers, manages watchers for reads and writes, 1157Provide read and write buffers, manages watchers for reads and writes,
1037supports raw and formatted I/O, I/O queued and fully transparent and 1158supports raw and formatted I/O, I/O queued and fully transparent and
1038non-blocking SSL/TLS (via L<AnyEvent::TLS>. 1159non-blocking SSL/TLS (via L<AnyEvent::TLS>).
1039 1160
1040=item L<AnyEvent::DNS> 1161=item L<AnyEvent::DNS>
1041 1162
1042Provides rich asynchronous DNS resolver capabilities. 1163Provides rich asynchronous DNS resolver capabilities.
1043 1164
1165=item L<AnyEvent::HTTP>, L<AnyEvent::IRC>, L<AnyEvent::XMPP>, L<AnyEvent::GPSD>, L<AnyEvent::IGS>, L<AnyEvent::FCP>
1166
1167Implement event-based interfaces to the protocols of the same name (for
1168the curious, IGS is the International Go Server and FCP is the Freenet
1169Client Protocol).
1170
1044=item L<AnyEvent::HTTP> 1171=item L<AnyEvent::AIO>
1045 1172
1046A simple-to-use HTTP library that is capable of making a lot of concurrent 1173Truly asynchronous (as opposed to non-blocking) I/O, should be in the
1047HTTP requests. 1174toolbox of every event programmer. AnyEvent::AIO transparently fuses
1175L<IO::AIO> and AnyEvent together, giving AnyEvent access to event-based
1176file I/O, and much more.
1177
1178=item L<AnyEvent::Filesys::Notify>
1179
1180AnyEvent is good for non-blocking stuff, but it can't detect file or
1181path changes (e.g. "watch this directory for new files", "watch this
1182file for changes"). The L<AnyEvent::Filesys::Notify> module promises to
1183do just that in a portbale fashion, supporting inotify on GNU/Linux and
1184some weird, without doubt broken, stuff on OS X to monitor files. It can
1185fall back to blocking scans at regular intervals transparently on other
1186platforms, so it's about as portable as it gets.
1187
1188(I haven't used it myself, but I haven't heard anybody complaining about
1189it yet).
1190
1191=item L<AnyEvent::DBI>
1192
1193Executes L<DBI> requests asynchronously in a proxy process for you,
1194notifying you in an event-based way when the operation is finished.
1048 1195
1049=item L<AnyEvent::HTTPD> 1196=item L<AnyEvent::HTTPD>
1050 1197
1051Provides a simple web application server framework. 1198A simple embedded webserver.
1052 1199
1053=item L<AnyEvent::FastPing> 1200=item L<AnyEvent::FastPing>
1054 1201
1055The fastest ping in the west. 1202The fastest ping in the west.
1056 1203
1057=item L<AnyEvent::DBI>
1058
1059Executes L<DBI> requests asynchronously in a proxy process.
1060
1061=item L<AnyEvent::AIO>
1062
1063Truly asynchronous I/O, should be in the toolbox of every event
1064programmer. AnyEvent::AIO transparently fuses L<IO::AIO> and AnyEvent
1065together.
1066
1067=item L<AnyEvent::BDB>
1068
1069Truly asynchronous Berkeley DB access. AnyEvent::BDB transparently fuses
1070L<BDB> and AnyEvent together.
1071
1072=item L<AnyEvent::GPSD>
1073
1074A non-blocking interface to gpsd, a daemon delivering GPS information.
1075
1076=item L<AnyEvent::IRC>
1077
1078AnyEvent based IRC client module family (replacing the older Net::IRC3).
1079
1080=item L<AnyEvent::XMPP>
1081
1082AnyEvent based XMPP (Jabber protocol) module family (replacing the older
1083Net::XMPP2>.
1084
1085=item L<AnyEvent::IGS>
1086
1087A non-blocking interface to the Internet Go Server protocol (used by
1088L<App::IGS>).
1089
1090=item L<Net::FCP>
1091
1092AnyEvent-based implementation of the Freenet Client Protocol, birthplace
1093of AnyEvent.
1094
1095=item L<Event::ExecFlow>
1096
1097High level API for event-based execution flow control.
1098
1099=item L<Coro> 1204=item L<Coro>
1100 1205
1101Has special support for AnyEvent via L<Coro::AnyEvent>. 1206Has special support for AnyEvent via L<Coro::AnyEvent>, which allows you
1207to simply invert the flow control - don't call us, we will call you:
1208
1209 async {
1210 Coro::AnyEvent::sleep 5; # creates a 5s timer and waits for it
1211 print "5 seconds later!\n";
1212
1213 Coro::AnyEvent::readable *STDIN; # uses an I/O watcher
1214 my $line = <STDIN>; # works for ttys
1215
1216 AnyEvent::HTTP::http_get "url", Coro::rouse_cb;
1217 my ($body, $hdr) = Coro::rouse_wait;
1218 };
1102 1219
1103=back 1220=back
1104 1221
1105=cut 1222=cut
1106 1223
1107package AnyEvent; 1224package AnyEvent;
1108 1225
1109# basically a tuned-down version of common::sense 1226# basically a tuned-down version of common::sense
1110sub common_sense { 1227sub common_sense {
1111 # no warnings 1228 # from common:.sense 3.4
1112 ${^WARNING_BITS} ^= ${^WARNING_BITS}; 1229 ${^WARNING_BITS} ^= ${^WARNING_BITS} ^ "\x3c\x3f\x33\x00\x0f\xf0\x0f\xc0\xf0\xfc\x33\x00";
1113 # use strict vars subs 1230 # use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl)
1114 $^H |= 0x00000600; 1231 $^H |= 0x00000600;
1115} 1232}
1116 1233
1117BEGIN { AnyEvent::common_sense } 1234BEGIN { AnyEvent::common_sense }
1118 1235
1119use Carp (); 1236use Carp ();
1120 1237
1121our $VERSION = '5.1'; 1238our $VERSION = '6.02';
1122our $MODEL; 1239our $MODEL;
1123
1124our $AUTOLOAD;
1125our @ISA; 1240our @ISA;
1126
1127our @REGISTRY; 1241our @REGISTRY;
1128
1129our $WIN32;
1130
1131our $VERBOSE; 1242our $VERBOSE;
1243our %PROTOCOL; # (ipv4|ipv6) => (1|2), higher numbers are preferred
1244our $MAX_SIGNAL_LATENCY = $ENV{PERL_ANYEVENT_MAX_SIGNAL_LATENCY} || 10; # executes after the BEGIN block below (tainting!)
1132 1245
1133BEGIN { 1246BEGIN {
1134 eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }"; 1247 require "AnyEvent/constants.pl";
1248
1135 eval "sub TAINT(){ " . (${^TAINT}*1) . " }"; 1249 eval "sub TAINT (){" . (${^TAINT}*1) . "}";
1136 1250
1137 delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV} 1251 delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}
1138 if ${^TAINT}; 1252 if ${^TAINT};
1139 1253
1140 $VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1; 1254 $ENV{"PERL_ANYEVENT_$_"} = $ENV{"AE_$_"}
1255 for grep s/^AE_// && !exists $ENV{"PERL_ANYEVENT_$_"}, keys %ENV;
1141 1256
1142} 1257 @ENV{grep /^PERL_ANYEVENT_/, keys %ENV} = ()
1258 if ${^TAINT};
1143 1259
1144our $MAX_SIGNAL_LATENCY = 10; 1260 # $ENV{PERL_ANYEVENT_xxx} now valid
1145 1261
1146our %PROTOCOL; # (ipv4|ipv6) => (1|2), higher numbers are preferred 1262 $VERBOSE = length $ENV{PERL_ANYEVENT_VERBOSE} ? $ENV{PERL_ANYEVENT_VERBOSE}*1 : 4;
1147 1263
1148{
1149 my $idx; 1264 my $idx;
1150 $PROTOCOL{$_} = ++$idx 1265 $PROTOCOL{$_} = ++$idx
1151 for reverse split /\s*,\s*/, 1266 for reverse split /\s*,\s*/,
1152 $ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6"; 1267 $ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6";
1153} 1268}
1154 1269
1270our @post_detect;
1271
1272sub post_detect(&) {
1273 my ($cb) = @_;
1274
1275 push @post_detect, $cb;
1276
1277 defined wantarray
1278 ? bless \$cb, "AnyEvent::Util::postdetect"
1279 : ()
1280}
1281
1282sub AnyEvent::Util::postdetect::DESTROY {
1283 @post_detect = grep $_ != ${$_[0]}, @post_detect;
1284}
1285
1286our $POSTPONE_W;
1287our @POSTPONE;
1288
1289sub _postpone_exec {
1290 undef $POSTPONE_W;
1291
1292 &{ shift @POSTPONE }
1293 while @POSTPONE;
1294}
1295
1296sub postpone(&) {
1297 push @POSTPONE, shift;
1298
1299 $POSTPONE_W ||= AE::timer (0, 0, \&_postpone_exec);
1300
1301 ()
1302}
1303
1304sub log($$;@) {
1305 # only load the big bloated module when we actually are about to log something
1306 if ($_[0] <= ($VERBOSE || 1)) { # also catches non-numeric levels(!) and fatal
1307 local ($!, $@);
1308 require AnyEvent::Log; # among other things, sets $VERBOSE to 9
1309 # AnyEvent::Log overwrites this function
1310 goto &log;
1311 }
1312
1313 0 # not logged
1314}
1315
1316sub logger($;$) {
1317 package AnyEvent::Log;
1318
1319 my ($level, $renabled) = @_;
1320
1321 $$renabled = $level <= $VERBOSE;
1322
1323 my $pkg = (caller)[0];
1324
1325 my $logger = [$pkg, $level, $renabled];
1326
1327 our %LOGGER;
1328 $LOGGER{$logger+0} = $logger;
1329
1330 return unless defined wantarray;
1331
1332 require AnyEvent::Util;
1333 my $guard = AnyEvent::Util::guard (sub {
1334 # "clean up"
1335 delete $LOGGER{$logger+0};
1336 });
1337
1338 sub {
1339 return 0 unless $$renabled;
1340
1341 $guard if 0; # keep guard alive, but don't cause runtime overhead
1342 require AnyEvent::Log unless $AnyEvent::Log::VERSION;
1343 package AnyEvent::Log;
1344 _log ($logger->[0], $level, @_) # logger->[0] has been converted at load time
1345 }
1346}
1347
1348if (length $ENV{PERL_ANYEVENT_LOG}) {
1349 require AnyEvent::Log; # AnyEvent::Log does the thing for us
1350}
1351
1155my @models = ( 1352our @models = (
1156 [EV:: => AnyEvent::Impl::EV:: , 1], 1353 [EV:: => AnyEvent::Impl::EV::],
1157 [AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl:: , 1], 1354 [AnyEvent::Loop:: => AnyEvent::Impl::Perl::],
1158 # everything below here will not (normally) be autoprobed 1355 # everything below here will not (normally) be autoprobed
1159 # as the pureperl backend should work everywhere 1356 # as the pure perl backend should work everywhere
1160 # and is usually faster 1357 # and is usually faster
1358 [Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package, so msut be near the top
1161 [Event:: => AnyEvent::Impl::Event::, 1], 1359 [Event:: => AnyEvent::Impl::Event::], # slow, stable
1162 [Glib:: => AnyEvent::Impl::Glib:: , 1], # becomes extremely slow with many watchers 1360 [Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers
1361 # everything below here should not be autoloaded
1163 [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy 1362 [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
1164 [Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package
1165 [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles 1363 [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
1166 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program 1364 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program
1167 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza 1365 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
1168 [Wx:: => AnyEvent::Impl::POE::], 1366 [Wx:: => AnyEvent::Impl::POE::],
1169 [Prima:: => AnyEvent::Impl::POE::], 1367 [Prima:: => AnyEvent::Impl::POE::],
1170 # IO::Async is just too broken - we would need workarounds for its 1368 [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # a bitch to autodetect
1171 # byzantine signal and broken child handling, among others. 1369 [Cocoa::EventLoop:: => AnyEvent::Impl::Cocoa::],
1172 # IO::Async is rather hard to detect, as it doesn't have any 1370 [FLTK:: => AnyEvent::Impl::FLTK::],
1173 # obvious default class.
1174 [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program
1175 [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program
1176 [IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program
1177 [AnyEvent::Impl::IOAsync:: => AnyEvent::Impl::IOAsync::], # requires special main program
1178); 1371);
1179 1372
1180our %method = map +($_ => 1), 1373our @isa_hook;
1374
1375sub _isa_set {
1376 my @pkg = ("AnyEvent", (map $_->[0], grep defined, @isa_hook), $MODEL);
1377
1378 @{"$pkg[$_-1]::ISA"} = $pkg[$_]
1379 for 1 .. $#pkg;
1380
1381 grep $_ && $_->[1], @isa_hook
1382 and AE::_reset ();
1383}
1384
1385# used for hooking AnyEvent::Strict and AnyEvent::Debug::Wrap into the class hierarchy
1386sub _isa_hook($$;$) {
1387 my ($i, $pkg, $reset_ae) = @_;
1388
1389 $isa_hook[$i] = $pkg ? [$pkg, $reset_ae] : undef;
1390
1391 _isa_set;
1392}
1393
1394# all autoloaded methods reserve the complete glob, not just the method slot.
1395# due to bugs in perls method cache implementation.
1181 qw(io timer time now now_update signal child idle condvar one_event DESTROY); 1396our @methods = qw(io timer time now now_update signal child idle condvar);
1182 1397
1183our @post_detect;
1184
1185sub post_detect(&) { 1398sub detect() {
1186 my ($cb) = @_; 1399 return $MODEL if $MODEL; # some programs keep references to detect
1187 1400
1188 if ($MODEL) { 1401 # IO::Async::Loop::AnyEvent is extremely evil, refuse to work with it
1189 $cb->(); 1402 # the author knows about the problems and what it does to AnyEvent as a whole
1403 # (and the ability of others to use AnyEvent), but simply wants to abuse AnyEvent
1404 # anyway.
1405 AnyEvent::log fatal => "AnyEvent: IO::Async::Loop::AnyEvent detected - this module is broken by design,\n"
1406 . "abuses internals and breaks AnyEvent, will not continue."
1407 if exists $INC{"IO/Async/Loop/AnyEvent.pm"};
1190 1408
1191 undef 1409 local $!; # for good measure
1410 local $SIG{__DIE__}; # we use eval
1411
1412 # free some memory
1413 *detect = sub () { $MODEL };
1414 # undef &func doesn't correctly update the method cache. grmbl.
1415 # so we delete the whole glob. grmbl.
1416 # otoh, perl doesn't let me undef an active usb, but it lets me free
1417 # a glob with an active sub. hrm. i hope it works, but perl is
1418 # usually buggy in this department. sigh.
1419 delete @{"AnyEvent::"}{@methods};
1420 undef @methods;
1421
1422 if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z0-9:]+)$/) {
1423 my $model = $1;
1424 $model = "AnyEvent::Impl::$model" unless $model =~ s/::$//;
1425 if (eval "require $model") {
1426 AnyEvent::log 7 => "loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.";
1427 $MODEL = $model;
1192 } else { 1428 } else {
1193 push @post_detect, $cb; 1429 AnyEvent::log 4 => "unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@";
1194 1430 }
1195 defined wantarray
1196 ? bless \$cb, "AnyEvent::Util::postdetect"
1197 : ()
1198 } 1431 }
1199}
1200 1432
1201sub AnyEvent::Util::postdetect::DESTROY { 1433 # check for already loaded models
1202 @post_detect = grep $_ != ${$_[0]}, @post_detect;
1203}
1204
1205sub detect() {
1206 unless ($MODEL) { 1434 unless ($MODEL) {
1207 local $SIG{__DIE__}; 1435 for (@REGISTRY, @models) {
1208 1436 my ($package, $model) = @$_;
1209 if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) { 1437 if (${"$package\::VERSION"} > 0) {
1210 my $model = "AnyEvent::Impl::$1";
1211 if (eval "require $model") { 1438 if (eval "require $model") {
1439 AnyEvent::log 7 => "autodetected model '$model', using it.";
1212 $MODEL = $model; 1440 $MODEL = $model;
1213 warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2; 1441 last;
1214 } else { 1442 }
1215 warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE;
1216 } 1443 }
1217 } 1444 }
1218 1445
1219 # check for already loaded models
1220 unless ($MODEL) { 1446 unless ($MODEL) {
1447 # try to autoload a model
1221 for (@REGISTRY, @models) { 1448 for (@REGISTRY, @models) {
1222 my ($package, $model) = @$_; 1449 my ($package, $model) = @$_;
1450 if (
1451 eval "require $package"
1223 if (${"$package\::VERSION"} > 0) { 1452 and ${"$package\::VERSION"} > 0
1224 if (eval "require $model") { 1453 and eval "require $model"
1454 ) {
1455 AnyEvent::log 7 => "autoloaded model '$model', using it.";
1225 $MODEL = $model; 1456 $MODEL = $model;
1226 warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2;
1227 last; 1457 last;
1228 }
1229 } 1458 }
1230 } 1459 }
1231 1460
1232 unless ($MODEL) {
1233 # try to autoload a model
1234 for (@REGISTRY, @models) {
1235 my ($package, $model, $autoload) = @$_;
1236 if (
1237 $autoload
1238 and eval "require $package"
1239 and ${"$package\::VERSION"} > 0
1240 and eval "require $model"
1241 ) {
1242 $MODEL = $model;
1243 warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2;
1244 last;
1245 }
1246 }
1247
1248 $MODEL 1461 $MODEL
1249 or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.\n"; 1462 or AnyEvent::log fatal => "AnyEvent: backend autodetection failed - did you properly install AnyEvent?";
1250 }
1251 } 1463 }
1252
1253 push @{"$MODEL\::ISA"}, "AnyEvent::Base";
1254
1255 unshift @ISA, $MODEL;
1256
1257 require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT};
1258
1259 (shift @post_detect)->() while @post_detect;
1260 } 1464 }
1261 1465
1466 # free memory only needed for probing
1467 undef @models;
1468 undef @REGISTRY;
1469
1470 push @{"$MODEL\::ISA"}, "AnyEvent::Base";
1471
1472 # now nuke some methods that are overridden by the backend.
1473 # SUPER usage is not allowed in these.
1474 for (qw(time signal child idle)) {
1475 undef &{"AnyEvent::Base::$_"}
1476 if defined &{"$MODEL\::$_"};
1477 }
1478
1479 _isa_set;
1480
1481 # we're officially open!
1482
1483 if ($ENV{PERL_ANYEVENT_STRICT}) {
1484 require AnyEvent::Strict;
1485 }
1486
1487 if ($ENV{PERL_ANYEVENT_DEBUG_WRAP}) {
1488 require AnyEvent::Debug;
1489 AnyEvent::Debug::wrap ($ENV{PERL_ANYEVENT_DEBUG_WRAP});
1490 }
1491
1492 if (length $ENV{PERL_ANYEVENT_DEBUG_SHELL}) {
1493 require AnyEvent::Socket;
1494 require AnyEvent::Debug;
1495
1496 my $shell = $ENV{PERL_ANYEVENT_DEBUG_SHELL};
1497 $shell =~ s/\$\$/$$/g;
1498
1499 my ($host, $service) = AnyEvent::Socket::parse_hostport ($shell);
1500 $AnyEvent::Debug::SHELL = AnyEvent::Debug::shell ($host, $service);
1501 }
1502
1503 # now the anyevent environment is set up as the user told us to, so
1504 # call the actual user code - post detects
1505
1506 (shift @post_detect)->() while @post_detect;
1507 undef @post_detect;
1508
1509 *post_detect = sub(&) {
1510 shift->();
1511
1512 undef
1513 };
1514
1262 $MODEL 1515 $MODEL
1263} 1516}
1264 1517
1265sub AUTOLOAD { 1518for my $name (@methods) {
1266 (my $func = $AUTOLOAD) =~ s/.*://; 1519 *$name = sub {
1267 1520 detect;
1268 $method{$func} 1521 # we use goto because
1269 or Carp::croak "$func: not a valid method for AnyEvent objects"; 1522 # a) it makes the thunk more transparent
1270 1523 # b) it allows us to delete the thunk later
1271 detect unless $MODEL; 1524 goto &{ UNIVERSAL::can AnyEvent => "SUPER::$name" }
1272 1525 };
1273 my $class = shift;
1274 $class->$func (@_);
1275} 1526}
1276 1527
1277# utility function to dup a filehandle. this is used by many backends 1528# utility function to dup a filehandle. this is used by many backends
1278# to support binding more than one watcher per filehandle (they usually 1529# to support binding more than one watcher per filehandle (they usually
1279# allow only one watcher per fd, so we dup it to get a different one). 1530# allow only one watcher per fd, so we dup it to get a different one).
1293 1544
1294=head1 SIMPLIFIED AE API 1545=head1 SIMPLIFIED AE API
1295 1546
1296Starting with version 5.0, AnyEvent officially supports a second, much 1547Starting with version 5.0, AnyEvent officially supports a second, much
1297simpler, API that is designed to reduce the calling, typing and memory 1548simpler, API that is designed to reduce the calling, typing and memory
1298overhead. 1549overhead by using function call syntax and a fixed number of parameters.
1299 1550
1300See the L<AE> manpage for details. 1551See the L<AE> manpage for details.
1301 1552
1302=cut 1553=cut
1303 1554
1304package AE; 1555package AE;
1305 1556
1306our $VERSION = $AnyEvent::VERSION; 1557our $VERSION = $AnyEvent::VERSION;
1307 1558
1559sub _reset() {
1560 eval q{
1561 # fall back to the main API by default - backends and AnyEvent::Base
1562 # implementations can overwrite these.
1563
1308sub io($$$) { 1564 sub io($$$) {
1309 AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2]) 1565 AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])
1310} 1566 }
1311 1567
1312sub timer($$$) { 1568 sub timer($$$) {
1313 AnyEvent->timer (after => $_[0], interval => $_[1], cb => $_[2]) 1569 AnyEvent->timer (after => $_[0], interval => $_[1], cb => $_[2])
1314} 1570 }
1315 1571
1316sub signal($$) { 1572 sub signal($$) {
1317 AnyEvent->signal (signal => $_[0], cb => $_[1]) 1573 AnyEvent->signal (signal => $_[0], cb => $_[1])
1318} 1574 }
1319 1575
1320sub child($$) { 1576 sub child($$) {
1321 AnyEvent->child (pid => $_[0], cb => $_[1]) 1577 AnyEvent->child (pid => $_[0], cb => $_[1])
1322} 1578 }
1323 1579
1324sub idle($) { 1580 sub idle($) {
1325 AnyEvent->idle (cb => $_[0]) 1581 AnyEvent->idle (cb => $_[0]);
1326} 1582 }
1327 1583
1328sub cv(;&) { 1584 sub cv(;&) {
1329 AnyEvent->condvar (@_ ? (cb => $_[0]) : ()) 1585 AnyEvent->condvar (@_ ? (cb => $_[0]) : ())
1330} 1586 }
1331 1587
1332sub now() { 1588 sub now() {
1333 AnyEvent->now 1589 AnyEvent->now
1334} 1590 }
1335 1591
1336sub now_update() { 1592 sub now_update() {
1337 AnyEvent->now_update 1593 AnyEvent->now_update
1338} 1594 }
1339 1595
1340sub time() { 1596 sub time() {
1341 AnyEvent->time 1597 AnyEvent->time
1598 }
1599
1600 *postpone = \&AnyEvent::postpone;
1601 *log = \&AnyEvent::log;
1602 };
1603 die if $@;
1342} 1604}
1605
1606BEGIN { _reset }
1343 1607
1344package AnyEvent::Base; 1608package AnyEvent::Base;
1345 1609
1346# default implementations for many methods 1610# default implementations for many methods
1347 1611
1348sub _time { 1612sub time {
1613 eval q{ # poor man's autoloading {}
1349 # probe for availability of Time::HiRes 1614 # probe for availability of Time::HiRes
1350 if (eval "use Time::HiRes (); Time::HiRes::time (); 1") { 1615 if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
1351 warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8; 1616 *time = sub { Time::HiRes::time () };
1352 *_time = \&Time::HiRes::time; 1617 *AE::time = \& Time::HiRes::time ;
1618 *now = \&time;
1619 AnyEvent::log 8 => "AnyEvent: using Time::HiRes for sub-second timing accuracy.";
1353 # if (eval "use POSIX (); (POSIX::times())... 1620 # if (eval "use POSIX (); (POSIX::times())...
1354 } else { 1621 } else {
1622 *time = sub { CORE::time };
1623 *AE::time = sub (){ CORE::time };
1624 *now = \&time;
1355 warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE; 1625 AnyEvent::log 3 => "using built-in time(), WARNING, no sub-second resolution!";
1356 *_time = sub { time }; # epic fail 1626 }
1357 } 1627 };
1628 die if $@;
1358 1629
1359 &_time 1630 &time
1360} 1631}
1361 1632
1362sub time { _time } 1633*now = \&time;
1363sub now { _time }
1364sub now_update { } 1634sub now_update { }
1365 1635
1636sub _poll {
1637 Carp::croak "$AnyEvent::MODEL does not support blocking waits. Caught";
1638}
1639
1366# default implementation for ->condvar 1640# default implementation for ->condvar
1641# in fact, the default should not be overwritten
1367 1642
1368sub condvar { 1643sub condvar {
1644 eval q{ # poor man's autoloading {}
1645 *condvar = sub {
1369 bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar" 1646 bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"
1647 };
1648
1649 *AE::cv = sub (;&) {
1650 bless { @_ ? (_ae_cb => shift) : () }, "AnyEvent::CondVar"
1651 };
1652 };
1653 die if $@;
1654
1655 &condvar
1370} 1656}
1371 1657
1372# default implementation for ->signal 1658# default implementation for ->signal
1373 1659
1374our $HAVE_ASYNC_INTERRUPT; 1660our $HAVE_ASYNC_INTERRUPT;
1375 1661
1376sub _have_async_interrupt() { 1662sub _have_async_interrupt() {
1377 $HAVE_ASYNC_INTERRUPT = 1*(!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT} 1663 $HAVE_ASYNC_INTERRUPT = 1*(!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT}
1378 && eval "use Async::Interrupt 1.0 (); 1") 1664 && eval "use Async::Interrupt 1.02 (); 1")
1379 unless defined $HAVE_ASYNC_INTERRUPT; 1665 unless defined $HAVE_ASYNC_INTERRUPT;
1380 1666
1381 $HAVE_ASYNC_INTERRUPT 1667 $HAVE_ASYNC_INTERRUPT
1382} 1668}
1383 1669
1384our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO); 1670our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);
1385our (%SIG_ASY, %SIG_ASY_W); 1671our (%SIG_ASY, %SIG_ASY_W);
1386our ($SIG_COUNT, $SIG_TW); 1672our ($SIG_COUNT, $SIG_TW);
1387 1673
1388sub _signal_exec {
1389 $HAVE_ASYNC_INTERRUPT
1390 ? $SIGPIPE_R->drain
1391 : sysread $SIGPIPE_R, my $dummy, 9;
1392
1393 while (%SIG_EV) {
1394 for (keys %SIG_EV) {
1395 delete $SIG_EV{$_};
1396 $_->() for values %{ $SIG_CB{$_} || {} };
1397 }
1398 }
1399}
1400
1401# install a dummy wakeup watcher to reduce signal catching latency 1674# install a dummy wakeup watcher to reduce signal catching latency
1675# used by Impls
1402sub _sig_add() { 1676sub _sig_add() {
1403 unless ($SIG_COUNT++) { 1677 unless ($SIG_COUNT++) {
1404 # try to align timer on a full-second boundary, if possible 1678 # try to align timer on a full-second boundary, if possible
1405 my $NOW = AE::now; 1679 my $NOW = AE::now;
1406 1680
1416 undef $SIG_TW 1690 undef $SIG_TW
1417 unless --$SIG_COUNT; 1691 unless --$SIG_COUNT;
1418} 1692}
1419 1693
1420our $_sig_name_init; $_sig_name_init = sub { 1694our $_sig_name_init; $_sig_name_init = sub {
1421 eval q{ # poor man's autoloading 1695 eval q{ # poor man's autoloading {}
1422 undef $_sig_name_init; 1696 undef $_sig_name_init;
1423 1697
1424 if (_have_async_interrupt) { 1698 if (_have_async_interrupt) {
1425 *sig2num = \&Async::Interrupt::sig2num; 1699 *sig2num = \&Async::Interrupt::sig2num;
1426 *sig2name = \&Async::Interrupt::sig2name; 1700 *sig2name = \&Async::Interrupt::sig2name;
1450 1724
1451sub signal { 1725sub signal {
1452 eval q{ # poor man's autoloading {} 1726 eval q{ # poor man's autoloading {}
1453 # probe for availability of Async::Interrupt 1727 # probe for availability of Async::Interrupt
1454 if (_have_async_interrupt) { 1728 if (_have_async_interrupt) {
1455 warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8; 1729 AnyEvent::log 8 => "using Async::Interrupt for race-free signal handling.";
1456 1730
1457 $SIGPIPE_R = new Async::Interrupt::EventPipe; 1731 $SIGPIPE_R = new Async::Interrupt::EventPipe;
1458 $SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec; 1732 $SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;
1459 1733
1460 } else { 1734 } else {
1461 warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8; 1735 AnyEvent::log 8 => "using emulated perl signal handling with latency timer.";
1462
1463 require Fcntl;
1464 1736
1465 if (AnyEvent::WIN32) { 1737 if (AnyEvent::WIN32) {
1466 require AnyEvent::Util; 1738 require AnyEvent::Util;
1467 1739
1468 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe (); 1740 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
1469 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R; 1741 AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R;
1470 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case 1742 AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case
1471 } else { 1743 } else {
1472 pipe $SIGPIPE_R, $SIGPIPE_W; 1744 pipe $SIGPIPE_R, $SIGPIPE_W;
1473 fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R; 1745 fcntl $SIGPIPE_R, AnyEvent::F_SETFL, AnyEvent::O_NONBLOCK if $SIGPIPE_R;
1474 fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case 1746 fcntl $SIGPIPE_W, AnyEvent::F_SETFL, AnyEvent::O_NONBLOCK if $SIGPIPE_W; # just in case
1475 1747
1476 # not strictly required, as $^F is normally 2, but let's make sure... 1748 # not strictly required, as $^F is normally 2, but let's make sure...
1477 fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; 1749 fcntl $SIGPIPE_R, AnyEvent::F_SETFD, AnyEvent::FD_CLOEXEC;
1478 fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; 1750 fcntl $SIGPIPE_W, AnyEvent::F_SETFD, AnyEvent::FD_CLOEXEC;
1479 } 1751 }
1480 1752
1481 $SIGPIPE_R 1753 $SIGPIPE_R
1482 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n"; 1754 or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1483 1755
1484 $SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec; 1756 $SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec;
1485 } 1757 }
1486 1758
1487 *signal = sub { 1759 *signal = $HAVE_ASYNC_INTERRUPT
1760 ? sub {
1488 my (undef, %arg) = @_; 1761 my (undef, %arg) = @_;
1489 1762
1490 my $signal = uc $arg{signal}
1491 or Carp::croak "required option 'signal' is missing";
1492
1493 if ($HAVE_ASYNC_INTERRUPT) {
1494 # async::interrupt 1763 # async::interrupt
1495
1496 $signal = sig2num $signal; 1764 my $signal = sig2num $arg{signal};
1497 $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; 1765 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1498 1766
1499 $SIG_ASY{$signal} ||= new Async::Interrupt 1767 $SIG_ASY{$signal} ||= new Async::Interrupt
1500 cb => sub { undef $SIG_EV{$signal} }, 1768 cb => sub { undef $SIG_EV{$signal} },
1501 signal => $signal, 1769 signal => $signal,
1502 pipe => [$SIGPIPE_R->filenos], 1770 pipe => [$SIGPIPE_R->filenos],
1503 pipe_autodrain => 0, 1771 pipe_autodrain => 0,
1504 ; 1772 ;
1505 1773
1506 } else { 1774 bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1775 }
1776 : sub {
1777 my (undef, %arg) = @_;
1778
1507 # pure perl 1779 # pure perl
1508
1509 # AE::Util has been loaded in signal
1510 $signal = sig2name $signal; 1780 my $signal = sig2name $arg{signal};
1511 $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; 1781 $SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1512 1782
1513 $SIG{$signal} ||= sub { 1783 $SIG{$signal} ||= sub {
1514 local $!; 1784 local $!;
1515 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV; 1785 syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
1516 undef $SIG_EV{$signal}; 1786 undef $SIG_EV{$signal};
1517 }; 1787 };
1518 1788
1519 # can't do signal processing without introducing races in pure perl, 1789 # can't do signal processing without introducing races in pure perl,
1520 # so limit the signal latency. 1790 # so limit the signal latency.
1521 _sig_add; 1791 _sig_add;
1522 }
1523 1792
1524 bless [$signal, $arg{cb}], "AnyEvent::Base::signal" 1793 bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1794 }
1525 }; 1795 ;
1526 1796
1527 *AnyEvent::Base::signal::DESTROY = sub { 1797 *AnyEvent::Base::signal::DESTROY = sub {
1528 my ($signal, $cb) = @{$_[0]}; 1798 my ($signal, $cb) = @{$_[0]};
1529 1799
1530 _sig_del; 1800 _sig_del;
1537 # print weird messages, or just unconditionally exit 1807 # print weird messages, or just unconditionally exit
1538 # instead of getting the default action. 1808 # instead of getting the default action.
1539 undef $SIG{$signal} 1809 undef $SIG{$signal}
1540 unless keys %{ $SIG_CB{$signal} }; 1810 unless keys %{ $SIG_CB{$signal} };
1541 }; 1811 };
1812
1813 *_signal_exec = sub {
1814 $HAVE_ASYNC_INTERRUPT
1815 ? $SIGPIPE_R->drain
1816 : sysread $SIGPIPE_R, (my $dummy), 9;
1817
1818 while (%SIG_EV) {
1819 for (keys %SIG_EV) {
1820 delete $SIG_EV{$_};
1821 &$_ for values %{ $SIG_CB{$_} || {} };
1822 }
1823 }
1824 };
1542 }; 1825 };
1543 die if $@; 1826 die if $@;
1827
1544 &signal 1828 &signal
1545} 1829}
1546 1830
1547# default implementation for ->child 1831# default implementation for ->child
1548 1832
1549our %PID_CB; 1833our %PID_CB;
1550our $CHLD_W; 1834our $CHLD_W;
1551our $CHLD_DELAY_W; 1835our $CHLD_DELAY_W;
1552our $WNOHANG;
1553 1836
1837# used by many Impl's
1554sub _emit_childstatus($$) { 1838sub _emit_childstatus($$) {
1555 my (undef, $rpid, $rstatus) = @_; 1839 my (undef, $rpid, $rstatus) = @_;
1556 1840
1557 $_->($rpid, $rstatus) 1841 $_->($rpid, $rstatus)
1558 for values %{ $PID_CB{$rpid} || {} }, 1842 for values %{ $PID_CB{$rpid} || {} },
1559 values %{ $PID_CB{0} || {} }; 1843 values %{ $PID_CB{0} || {} };
1560} 1844}
1561 1845
1562sub _sigchld {
1563 my $pid;
1564
1565 AnyEvent->_emit_childstatus ($pid, $?)
1566 while ($pid = waitpid -1, $WNOHANG) > 0;
1567}
1568
1569sub child { 1846sub child {
1847 eval q{ # poor man's autoloading {}
1848 *_sigchld = sub {
1849 my $pid;
1850
1851 AnyEvent->_emit_childstatus ($pid, $?)
1852 while ($pid = waitpid -1, WNOHANG) > 0;
1853 };
1854
1855 *child = sub {
1570 my (undef, %arg) = @_; 1856 my (undef, %arg) = @_;
1571 1857
1572 defined (my $pid = $arg{pid} + 0) 1858 my $pid = $arg{pid};
1573 or Carp::croak "required option 'pid' is missing"; 1859 my $cb = $arg{cb};
1574 1860
1575 $PID_CB{$pid}{$arg{cb}} = $arg{cb}; 1861 $PID_CB{$pid}{$cb+0} = $cb;
1576 1862
1577 # WNOHANG is almost cetrainly 1 everywhere
1578 $WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/
1579 ? 1
1580 : eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1;
1581
1582 unless ($CHLD_W) { 1863 unless ($CHLD_W) {
1583 $CHLD_W = AE::signal CHLD => \&_sigchld; 1864 $CHLD_W = AE::signal CHLD => \&_sigchld;
1584 # child could be a zombie already, so make at least one round 1865 # child could be a zombie already, so make at least one round
1585 &_sigchld; 1866 &_sigchld;
1586 } 1867 }
1587 1868
1588 bless [$pid, $arg{cb}], "AnyEvent::Base::child" 1869 bless [$pid, $cb+0], "AnyEvent::Base::child"
1589} 1870 };
1590 1871
1591sub AnyEvent::Base::child::DESTROY { 1872 *AnyEvent::Base::child::DESTROY = sub {
1592 my ($pid, $cb) = @{$_[0]}; 1873 my ($pid, $icb) = @{$_[0]};
1593 1874
1594 delete $PID_CB{$pid}{$cb}; 1875 delete $PID_CB{$pid}{$icb};
1595 delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} }; 1876 delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };
1596 1877
1597 undef $CHLD_W unless keys %PID_CB; 1878 undef $CHLD_W unless keys %PID_CB;
1879 };
1880 };
1881 die if $@;
1882
1883 &child
1598} 1884}
1599 1885
1600# idle emulation is done by simply using a timer, regardless 1886# idle emulation is done by simply using a timer, regardless
1601# of whether the process is idle or not, and not letting 1887# of whether the process is idle or not, and not letting
1602# the callback use more than 50% of the time. 1888# the callback use more than 50% of the time.
1603sub idle { 1889sub idle {
1890 eval q{ # poor man's autoloading {}
1891 *idle = sub {
1604 my (undef, %arg) = @_; 1892 my (undef, %arg) = @_;
1605 1893
1606 my ($cb, $w, $rcb) = $arg{cb}; 1894 my ($cb, $w, $rcb) = $arg{cb};
1607 1895
1608 $rcb = sub { 1896 $rcb = sub {
1609 if ($cb) { 1897 if ($cb) {
1610 $w = _time; 1898 $w = AE::time;
1611 &$cb; 1899 &$cb;
1612 $w = _time - $w; 1900 $w = AE::time - $w;
1613 1901
1614 # never use more then 50% of the time for the idle watcher, 1902 # never use more then 50% of the time for the idle watcher,
1615 # within some limits 1903 # within some limits
1616 $w = 0.0001 if $w < 0.0001; 1904 $w = 0.0001 if $w < 0.0001;
1617 $w = 5 if $w > 5; 1905 $w = 5 if $w > 5;
1618 1906
1619 $w = AE::timer $w, 0, $rcb; 1907 $w = AE::timer $w, 0, $rcb;
1620 } else { 1908 } else {
1621 # clean up... 1909 # clean up...
1622 undef $w; 1910 undef $w;
1623 undef $rcb; 1911 undef $rcb;
1912 }
1913 };
1914
1915 $w = AE::timer 0.05, 0, $rcb;
1916
1917 bless \\$cb, "AnyEvent::Base::idle"
1624 } 1918 };
1919
1920 *AnyEvent::Base::idle::DESTROY = sub {
1921 undef $${$_[0]};
1922 };
1625 }; 1923 };
1924 die if $@;
1626 1925
1627 $w = AE::timer 0.05, 0, $rcb; 1926 &idle
1628
1629 bless \\$cb, "AnyEvent::Base::idle"
1630}
1631
1632sub AnyEvent::Base::idle::DESTROY {
1633 undef $${$_[0]};
1634} 1927}
1635 1928
1636package AnyEvent::CondVar; 1929package AnyEvent::CondVar;
1637 1930
1638our @ISA = AnyEvent::CondVar::Base::; 1931our @ISA = AnyEvent::CondVar::Base::;
1932
1933# only to be used for subclassing
1934sub new {
1935 my $class = shift;
1936 bless AnyEvent->condvar (@_), $class
1937}
1639 1938
1640package AnyEvent::CondVar::Base; 1939package AnyEvent::CondVar::Base;
1641 1940
1642#use overload 1941#use overload
1643# '&{}' => sub { my $self = shift; sub { $self->send (@_) } }, 1942# '&{}' => sub { my $self = shift; sub { $self->send (@_) } },
1653 1952
1654sub _send { 1953sub _send {
1655 # nop 1954 # nop
1656} 1955}
1657 1956
1957sub _wait {
1958 AnyEvent->_poll until $_[0]{_ae_sent};
1959}
1960
1658sub send { 1961sub send {
1659 my $cv = shift; 1962 my $cv = shift;
1660 $cv->{_ae_sent} = [@_]; 1963 $cv->{_ae_sent} = [@_];
1661 (delete $cv->{_ae_cb})->($cv) if $cv->{_ae_cb}; 1964 (delete $cv->{_ae_cb})->($cv) if $cv->{_ae_cb};
1662 $cv->_send; 1965 $cv->_send;
1669 1972
1670sub ready { 1973sub ready {
1671 $_[0]{_ae_sent} 1974 $_[0]{_ae_sent}
1672} 1975}
1673 1976
1674sub _wait {
1675 $WAITING
1676 and !$_[0]{_ae_sent}
1677 and Carp::croak "AnyEvent::CondVar: recursive blocking wait detected";
1678
1679 local $WAITING = 1;
1680 AnyEvent->one_event while !$_[0]{_ae_sent};
1681}
1682
1683sub recv { 1977sub recv {
1978 unless ($_[0]{_ae_sent}) {
1979 $WAITING
1980 and Carp::croak "AnyEvent::CondVar: recursive blocking wait attempted";
1981
1982 local $WAITING = 1;
1684 $_[0]->_wait; 1983 $_[0]->_wait;
1984 }
1685 1985
1686 Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak}; 1986 $_[0]{_ae_croak}
1687 wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0] 1987 and Carp::croak $_[0]{_ae_croak};
1988
1989 wantarray
1990 ? @{ $_[0]{_ae_sent} }
1991 : $_[0]{_ae_sent}[0]
1688} 1992}
1689 1993
1690sub cb { 1994sub cb {
1691 my $cv = shift; 1995 my $cv = shift;
1692 1996
1708 &{ $_[0]{_ae_end_cb} || sub { $_[0]->send } }; 2012 &{ $_[0]{_ae_end_cb} || sub { $_[0]->send } };
1709} 2013}
1710 2014
1711# undocumented/compatibility with pre-3.4 2015# undocumented/compatibility with pre-3.4
1712*broadcast = \&send; 2016*broadcast = \&send;
1713*wait = \&_wait; 2017*wait = \&recv;
1714 2018
1715=head1 ERROR AND EXCEPTION HANDLING 2019=head1 ERROR AND EXCEPTION HANDLING
1716 2020
1717In general, AnyEvent does not do any error handling - it relies on the 2021In general, AnyEvent does not do any error handling - it relies on the
1718caller to do that if required. The L<AnyEvent::Strict> module (see also 2022caller to do that if required. The L<AnyEvent::Strict> module (see also
1730$Event/EV::DIED->() >>, L<Glib> uses C<< install_exception_handler >> and 2034$Event/EV::DIED->() >>, L<Glib> uses C<< install_exception_handler >> and
1731so on. 2035so on.
1732 2036
1733=head1 ENVIRONMENT VARIABLES 2037=head1 ENVIRONMENT VARIABLES
1734 2038
1735The following environment variables are used by this module or its 2039AnyEvent supports a number of environment variables that tune the
1736submodules. 2040runtime behaviour. They are usually evaluated when AnyEvent is
2041loaded, initialised, or a submodule that uses them is loaded. Many of
2042them also cause AnyEvent to load additional modules - for example,
2043C<PERL_ANYEVENT_DEBUG_WRAP> causes the L<AnyEvent::Debug> module to be
2044loaded.
1737 2045
1738Note that AnyEvent will remove I<all> environment variables starting with 2046All the environment variables documented here start with
1739C<PERL_ANYEVENT_> from C<%ENV> when it is loaded while taint mode is 2047C<PERL_ANYEVENT_>, which is what AnyEvent considers its own
1740enabled. 2048namespace. Other modules are encouraged (but by no means required) to use
2049C<PERL_ANYEVENT_SUBMODULE> if they have registered the AnyEvent::Submodule
2050namespace on CPAN, for any submodule. For example, L<AnyEvent::HTTP> could
2051be expected to use C<PERL_ANYEVENT_HTTP_PROXY> (it should not access env
2052variables starting with C<AE_>, see below).
2053
2054All variables can also be set via the C<AE_> prefix, that is, instead
2055of setting C<PERL_ANYEVENT_VERBOSE> you can also set C<AE_VERBOSE>. In
2056case there is a clash btween anyevent and another program that uses
2057C<AE_something> you can set the corresponding C<PERL_ANYEVENT_something>
2058variable to the empty string, as those variables take precedence.
2059
2060When AnyEvent is first loaded, it copies all C<AE_xxx> env variables
2061to their C<PERL_ANYEVENT_xxx> counterpart unless that variable already
2062exists. If taint mode is on, then AnyEvent will remove I<all> environment
2063variables starting with C<PERL_ANYEVENT_> from C<%ENV> (or replace them
2064with C<undef> or the empty string, if the corresaponding C<AE_> variable
2065is set).
2066
2067The exact algorithm is currently:
2068
2069 1. if taint mode enabled, delete all PERL_ANYEVENT_xyz variables from %ENV
2070 2. copy over AE_xyz to PERL_ANYEVENT_xyz unless the latter alraedy exists
2071 3. if taint mode enabled, set all PERL_ANYEVENT_xyz variables to undef.
2072
2073This ensures that child processes will not see the C<AE_> variables.
2074
2075The following environment variables are currently known to AnyEvent:
1741 2076
1742=over 4 2077=over 4
1743 2078
1744=item C<PERL_ANYEVENT_VERBOSE> 2079=item C<PERL_ANYEVENT_VERBOSE>
1745 2080
1746By default, AnyEvent will be completely silent except in fatal 2081By default, AnyEvent will only log messages with loglevel C<3>
1747conditions. You can set this environment variable to make AnyEvent more 2082(C<critical>) or higher (see L<AnyEvent::Log>). You can set this
2083environment variable to a numerical loglevel to make AnyEvent more (or
1748talkative. 2084less) talkative.
1749 2085
2086If you want to do more than just set the global logging level
2087you should have a look at C<PERL_ANYEVENT_LOG>, which allows much more
2088complex specifications.
2089
2090When set to C<0> (C<off>), then no messages whatsoever will be logged with
2091the default logging settings.
2092
1750When set to C<1> or higher, causes AnyEvent to warn about unexpected 2093When set to C<5> or higher (C<warn>), causes AnyEvent to warn about
1751conditions, such as not being able to load the event model specified by 2094unexpected conditions, such as not being able to load the event model
1752C<PERL_ANYEVENT_MODEL>. 2095specified by C<PERL_ANYEVENT_MODEL>, or a guard callback throwing an
2096exception - this is the minimum recommended level.
1753 2097
1754When set to C<2> or higher, cause AnyEvent to report to STDERR which event 2098When set to C<7> or higher (info), cause AnyEvent to report which event model it
1755model it chooses. 2099chooses.
1756 2100
1757When set to C<8> or higher, then AnyEvent will report extra information on 2101When set to C<8> or higher (debug), then AnyEvent will report extra information on
1758which optional modules it loads and how it implements certain features. 2102which optional modules it loads and how it implements certain features.
2103
2104=item C<PERL_ANYEVENT_LOG>
2105
2106Accepts rather complex logging specifications. For example, you could log
2107all C<debug> messages of some module to stderr, warnings and above to
2108stderr, and errors and above to syslog, with:
2109
2110 PERL_ANYEVENT_LOG=Some::Module=debug,+log:filter=warn,+%syslog:%syslog=error,syslog
2111
2112For the rather extensive details, see L<AnyEvent::Log>.
2113
2114This variable is evaluated when AnyEvent (or L<AnyEvent::Log>) is loaded,
2115so will take effect even before AnyEvent has initialised itself.
2116
2117Note that specifying this environment variable causes the L<AnyEvent::Log>
2118module to be loaded, while C<PERL_ANYEVENT_VERBOSE> does not, so only
2119using the latter saves a few hundred kB of memory until the first message
2120is being logged.
1759 2121
1760=item C<PERL_ANYEVENT_STRICT> 2122=item C<PERL_ANYEVENT_STRICT>
1761 2123
1762AnyEvent does not do much argument checking by default, as thorough 2124AnyEvent does not do much argument checking by default, as thorough
1763argument checking is very costly. Setting this variable to a true value 2125argument checking is very costly. Setting this variable to a true value
1765check the arguments passed to most method calls. If it finds any problems, 2127check the arguments passed to most method calls. If it finds any problems,
1766it will croak. 2128it will croak.
1767 2129
1768In other words, enables "strict" mode. 2130In other words, enables "strict" mode.
1769 2131
1770Unlike C<use strict> (or it's modern cousin, C<< use L<common::sense> 2132Unlike C<use strict> (or its modern cousin, C<< use L<common::sense>
1771>>, it is definitely recommended to keep it off in production. Keeping 2133>>, it is definitely recommended to keep it off in production. Keeping
1772C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs 2134C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs
1773can be very useful, however. 2135can be very useful, however.
1774 2136
2137=item C<PERL_ANYEVENT_DEBUG_SHELL>
2138
2139If this env variable is nonempty, then its contents will be interpreted by
2140C<AnyEvent::Socket::parse_hostport> and C<AnyEvent::Debug::shell> (after
2141replacing every occurance of C<$$> by the process pid). The shell object
2142is saved in C<$AnyEvent::Debug::SHELL>.
2143
2144This happens when the first watcher is created.
2145
2146For example, to bind a debug shell on a unix domain socket in
2147F<< /tmp/debug<pid>.sock >>, you could use this:
2148
2149 PERL_ANYEVENT_DEBUG_SHELL=/tmp/debug\$\$.sock perlprog
2150 # connect with e.g.: socat readline /tmp/debug123.sock
2151
2152Or to bind to tcp port 4545 on localhost:
2153
2154 PERL_ANYEVENT_DEBUG_SHELL=127.0.0.1:4545 perlprog
2155 # connect with e.g.: telnet localhost 4545
2156
2157Note that creating sockets in F</tmp> or on localhost is very unsafe on
2158multiuser systems.
2159
2160=item C<PERL_ANYEVENT_DEBUG_WRAP>
2161
2162Can be set to C<0>, C<1> or C<2> and enables wrapping of all watchers for
2163debugging purposes. See C<AnyEvent::Debug::wrap> for details.
2164
1775=item C<PERL_ANYEVENT_MODEL> 2165=item C<PERL_ANYEVENT_MODEL>
1776 2166
1777This can be used to specify the event model to be used by AnyEvent, before 2167This can be used to specify the event model to be used by AnyEvent, before
1778auto detection and -probing kicks in. It must be a string consisting 2168auto detection and -probing kicks in.
1779entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended 2169
2170It normally is a string consisting entirely of ASCII letters (e.g. C<EV>
2171or C<IOAsync>). The string C<AnyEvent::Impl::> gets prepended and the
1780and the resulting module name is loaded and if the load was successful, 2172resulting module name is loaded and - if the load was successful - used as
1781used as event model. If it fails to load AnyEvent will proceed with 2173event model backend. If it fails to load then AnyEvent will proceed with
1782auto detection and -probing. 2174auto detection and -probing.
1783 2175
1784This functionality might change in future versions. 2176If the string ends with C<::> instead (e.g. C<AnyEvent::Impl::EV::>) then
2177nothing gets prepended and the module name is used as-is (hint: C<::> at
2178the end of a string designates a module name and quotes it appropriately).
1785 2179
1786For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you 2180For example, to force the pure perl model (L<AnyEvent::Loop::Perl>) you
1787could start your program like this: 2181could start your program like this:
1788 2182
1789 PERL_ANYEVENT_MODEL=Perl perl ... 2183 PERL_ANYEVENT_MODEL=Perl perl ...
1790 2184
1791=item C<PERL_ANYEVENT_PROTOCOLS> 2185=item C<PERL_ANYEVENT_PROTOCOLS>
1807but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4> 2201but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4>
1808- only support IPv4, never try to resolve or contact IPv6 2202- only support IPv4, never try to resolve or contact IPv6
1809addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or 2203addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or
1810IPv6, but prefer IPv6 over IPv4. 2204IPv6, but prefer IPv6 over IPv4.
1811 2205
2206=item C<PERL_ANYEVENT_HOSTS>
2207
2208This variable, if specified, overrides the F</etc/hosts> file used by
2209L<AnyEvent::Socket>C<::resolve_sockaddr>, i.e. hosts aliases will be read
2210from that file instead.
2211
1812=item C<PERL_ANYEVENT_EDNS0> 2212=item C<PERL_ANYEVENT_EDNS0>
1813 2213
1814Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension 2214Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension for
1815for DNS. This extension is generally useful to reduce DNS traffic, but 2215DNS. This extension is generally useful to reduce DNS traffic, especially
1816some (broken) firewalls drop such DNS packets, which is why it is off by 2216when DNSSEC is involved, but some (broken) firewalls drop such DNS
1817default. 2217packets, which is why it is off by default.
1818 2218
1819Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce 2219Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce
1820EDNS0 in its DNS requests. 2220EDNS0 in its DNS requests.
1821 2221
1822=item C<PERL_ANYEVENT_MAX_FORKS> 2222=item C<PERL_ANYEVENT_MAX_FORKS>
1828 2228
1829The default value for the C<max_outstanding> parameter for the default DNS 2229The default value for the C<max_outstanding> parameter for the default DNS
1830resolver - this is the maximum number of parallel DNS requests that are 2230resolver - this is the maximum number of parallel DNS requests that are
1831sent to the DNS server. 2231sent to the DNS server.
1832 2232
2233=item C<PERL_ANYEVENT_MAX_SIGNAL_LATENCY>
2234
2235Perl has inherently racy signal handling (you can basically choose between
2236losing signals and memory corruption) - pure perl event loops (including
2237C<AnyEvent::Loop>, when C<Async::Interrupt> isn't available) therefore
2238have to poll regularly to avoid losing signals.
2239
2240Some event loops are racy, but don't poll regularly, and some event loops
2241are written in C but are still racy. For those event loops, AnyEvent
2242installs a timer that regularly wakes up the event loop.
2243
2244By default, the interval for this timer is C<10> seconds, but you can
2245override this delay with this environment variable (or by setting
2246the C<$AnyEvent::MAX_SIGNAL_LATENCY> variable before creating signal
2247watchers).
2248
2249Lower values increase CPU (and energy) usage, higher values can introduce
2250long delays when reaping children or waiting for signals.
2251
2252The L<AnyEvent::Async> module, if available, will be used to avoid this
2253polling (with most event loops).
2254
1833=item C<PERL_ANYEVENT_RESOLV_CONF> 2255=item C<PERL_ANYEVENT_RESOLV_CONF>
1834 2256
1835The file to use instead of F</etc/resolv.conf> (or OS-specific 2257The absolute path to a F<resolv.conf>-style file to use instead of
1836configuration) in the default resolver. When set to the empty string, no 2258F</etc/resolv.conf> (or the OS-specific configuration) in the default
1837default config will be used. 2259resolver, or the empty string to select the default configuration.
1838 2260
1839=item C<PERL_ANYEVENT_CA_FILE>, C<PERL_ANYEVENT_CA_PATH>. 2261=item C<PERL_ANYEVENT_CA_FILE>, C<PERL_ANYEVENT_CA_PATH>.
1840 2262
1841When neither C<ca_file> nor C<ca_path> was specified during 2263When neither C<ca_file> nor C<ca_path> was specified during
1842L<AnyEvent::TLS> context creation, and either of these environment 2264L<AnyEvent::TLS> context creation, and either of these environment
1843variables exist, they will be used to specify CA certificate locations 2265variables are nonempty, they will be used to specify CA certificate
1844instead of a system-dependent default. 2266locations instead of a system-dependent default.
1845 2267
1846=item C<PERL_ANYEVENT_AVOID_GUARD> and C<PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT> 2268=item C<PERL_ANYEVENT_AVOID_GUARD> and C<PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT>
1847 2269
1848When these are set to C<1>, then the respective modules are not 2270When these are set to C<1>, then the respective modules are not
1849loaded. Mostly good for testing AnyEvent itself. 2271loaded. Mostly good for testing AnyEvent itself.
1912 warn "read: $input\n"; # output what has been read 2334 warn "read: $input\n"; # output what has been read
1913 $cv->send if $input =~ /^q/i; # quit program if /^q/i 2335 $cv->send if $input =~ /^q/i; # quit program if /^q/i
1914 }, 2336 },
1915 ); 2337 );
1916 2338
1917 my $time_watcher; # can only be used once
1918
1919 sub new_timer {
1920 $timer = AnyEvent->timer (after => 1, cb => sub { 2339 my $time_watcher = AnyEvent->timer (after => 1, interval => 1, cb => sub {
1921 warn "timeout\n"; # print 'timeout' about every second 2340 warn "timeout\n"; # print 'timeout' at most every second
1922 &new_timer; # and restart the time
1923 }); 2341 });
1924 }
1925
1926 new_timer; # create first timer
1927 2342
1928 $cv->recv; # wait until user enters /^q/i 2343 $cv->recv; # wait until user enters /^q/i
1929 2344
1930=head1 REAL-WORLD EXAMPLE 2345=head1 REAL-WORLD EXAMPLE
1931 2346
2004 2419
2005The actual code goes further and collects all errors (C<die>s, exceptions) 2420The actual code goes further and collects all errors (C<die>s, exceptions)
2006that occurred during request processing. The C<result> method detects 2421that occurred during request processing. The C<result> method detects
2007whether an exception as thrown (it is stored inside the $txn object) 2422whether an exception as thrown (it is stored inside the $txn object)
2008and just throws the exception, which means connection errors and other 2423and just throws the exception, which means connection errors and other
2009problems get reported tot he code that tries to use the result, not in a 2424problems get reported to the code that tries to use the result, not in a
2010random callback. 2425random callback.
2011 2426
2012All of this enables the following usage styles: 2427All of this enables the following usage styles:
2013 2428
20141. Blocking: 24291. Blocking:
2188(even when used without AnyEvent), but most event loops have acceptable 2603(even when used without AnyEvent), but most event loops have acceptable
2189performance with or without AnyEvent. 2604performance with or without AnyEvent.
2190 2605
2191=item * The overhead AnyEvent adds is usually much smaller than the overhead of 2606=item * The overhead AnyEvent adds is usually much smaller than the overhead of
2192the actual event loop, only with extremely fast event loops such as EV 2607the actual event loop, only with extremely fast event loops such as EV
2193adds AnyEvent significant overhead. 2608does AnyEvent add significant overhead.
2194 2609
2195=item * You should avoid POE like the plague if you want performance or 2610=item * You should avoid POE like the plague if you want performance or
2196reasonable memory usage. 2611reasonable memory usage.
2197 2612
2198=back 2613=back
2375As you can see, the AnyEvent + EV combination even beats the 2790As you can see, the AnyEvent + EV combination even beats the
2376hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl 2791hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl
2377backend easily beats IO::Lambda and POE. 2792backend easily beats IO::Lambda and POE.
2378 2793
2379And even the 100% non-blocking version written using the high-level (and 2794And even the 100% non-blocking version written using the high-level (and
2380slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda by a 2795slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda
2381large margin, even though it does all of DNS, tcp-connect and socket I/O 2796higher level ("unoptimised") abstractions by a large margin, even though
2382in a non-blocking way. 2797it does all of DNS, tcp-connect and socket I/O in a non-blocking way.
2383 2798
2384The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and 2799The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and
2385F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are 2800F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are
2386part of the IO::lambda distribution and were used without any changes. 2801part of the IO::Lambda distribution and were used without any changes.
2387 2802
2388 2803
2389=head1 SIGNALS 2804=head1 SIGNALS
2390 2805
2391AnyEvent currently installs handlers for these signals: 2806AnyEvent currently installs handlers for these signals:
2428 unless defined $SIG{PIPE}; 2843 unless defined $SIG{PIPE};
2429 2844
2430=head1 RECOMMENDED/OPTIONAL MODULES 2845=head1 RECOMMENDED/OPTIONAL MODULES
2431 2846
2432One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and 2847One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and
2433it's built-in modules) are required to use it. 2848its built-in modules) are required to use it.
2434 2849
2435That does not mean that AnyEvent won't take advantage of some additional 2850That does not mean that AnyEvent won't take advantage of some additional
2436modules if they are installed. 2851modules if they are installed.
2437 2852
2438This section epxlains which additional modules will be used, and how they 2853This section explains which additional modules will be used, and how they
2439affect AnyEvent's operetion. 2854affect AnyEvent's operation.
2440 2855
2441=over 4 2856=over 4
2442 2857
2443=item L<Async::Interrupt> 2858=item L<Async::Interrupt>
2444 2859
2449catch the signals) with some delay (default is 10 seconds, look for 2864catch the signals) with some delay (default is 10 seconds, look for
2450C<$AnyEvent::MAX_SIGNAL_LATENCY>). 2865C<$AnyEvent::MAX_SIGNAL_LATENCY>).
2451 2866
2452If this module is available, then it will be used to implement signal 2867If this module is available, then it will be used to implement signal
2453catching, which means that signals will not be delayed, and the event loop 2868catching, which means that signals will not be delayed, and the event loop
2454will not be interrupted regularly, which is more efficient (And good for 2869will not be interrupted regularly, which is more efficient (and good for
2455battery life on laptops). 2870battery life on laptops).
2456 2871
2457This affects not just the pure-perl event loop, but also other event loops 2872This affects not just the pure-perl event loop, but also other event loops
2458that have no signal handling on their own (e.g. Glib, Tk, Qt). 2873that have no signal handling on their own (e.g. Glib, Tk, Qt).
2459 2874
2471automatic timer adjustments even when no monotonic clock is available, 2886automatic timer adjustments even when no monotonic clock is available,
2472can take avdantage of advanced kernel interfaces such as C<epoll> and 2887can take avdantage of advanced kernel interfaces such as C<epoll> and
2473C<kqueue>, and is the fastest backend I<by far>. You can even embed 2888C<kqueue>, and is the fastest backend I<by far>. You can even embed
2474L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>). 2889L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>).
2475 2890
2891If you only use backends that rely on another event loop (e.g. C<Tk>),
2892then this module will do nothing for you.
2893
2476=item L<Guard> 2894=item L<Guard>
2477 2895
2478The guard module, when used, will be used to implement 2896The guard module, when used, will be used to implement
2479C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a 2897C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a
2480lot less memory), but otherwise doesn't affect guard operation much. It is 2898lot less memory), but otherwise doesn't affect guard operation much. It is
2481purely used for performance. 2899purely used for performance.
2482 2900
2483=item L<JSON> and L<JSON::XS> 2901=item L<JSON> and L<JSON::XS>
2484 2902
2485This module is required when you want to read or write JSON data via 2903One of these modules is required when you want to read or write JSON data
2486L<AnyEvent::Handle>. It is also written in pure-perl, but can take 2904via L<AnyEvent::Handle>. L<JSON> is also written in pure-perl, but can take
2487advantage of the ultra-high-speed L<JSON::XS> module when it is installed. 2905advantage of the ultra-high-speed L<JSON::XS> module when it is installed.
2488
2489In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is
2490installed.
2491 2906
2492=item L<Net::SSLeay> 2907=item L<Net::SSLeay>
2493 2908
2494Implementing TLS/SSL in Perl is certainly interesting, but not very 2909Implementing TLS/SSL in Perl is certainly interesting, but not very
2495worthwhile: If this module is installed, then L<AnyEvent::Handle> (with 2910worthwhile: If this module is installed, then L<AnyEvent::Handle> (with
2496the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL. 2911the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL.
2497 2912
2498=item L<Time::HiRes> 2913=item L<Time::HiRes>
2499 2914
2500This module is part of perl since release 5.008. It will be used when the 2915This module is part of perl since release 5.008. It will be used when the
2501chosen event library does not come with a timing source on it's own. The 2916chosen event library does not come with a timing source of its own. The
2502pure-perl event loop (L<AnyEvent::Impl::Perl>) will additionally use it to 2917pure-perl event loop (L<AnyEvent::Loop>) will additionally load it to
2503try to use a monotonic clock for timing stability. 2918try to use a monotonic clock for timing stability.
2504 2919
2505=back 2920=back
2506 2921
2507 2922
2508=head1 FORK 2923=head1 FORK
2509 2924
2510Most event libraries are not fork-safe. The ones who are usually are 2925Most event libraries are not fork-safe. The ones who are usually are
2511because they rely on inefficient but fork-safe C<select> or C<poll> 2926because they rely on inefficient but fork-safe C<select> or C<poll> calls
2512calls. Only L<EV> is fully fork-aware. 2927- higher performance APIs such as BSD's kqueue or the dreaded Linux epoll
2928are usually badly thought-out hacks that are incompatible with fork in
2929one way or another. Only L<EV> is fully fork-aware and ensures that you
2930continue event-processing in both parent and child (or both, if you know
2931what you are doing).
2932
2933This means that, in general, you cannot fork and do event processing in
2934the child if the event library was initialised before the fork (which
2935usually happens when the first AnyEvent watcher is created, or the library
2936is loaded).
2513 2937
2514If you have to fork, you must either do so I<before> creating your first 2938If you have to fork, you must either do so I<before> creating your first
2515watcher OR you must not use AnyEvent at all in the child OR you must do 2939watcher OR you must not use AnyEvent at all in the child OR you must do
2516something completely out of the scope of AnyEvent. 2940something completely out of the scope of AnyEvent.
2941
2942The problem of doing event processing in the parent I<and> the child
2943is much more complicated: even for backends that I<are> fork-aware or
2944fork-safe, their behaviour is not usually what you want: fork clones all
2945watchers, that means all timers, I/O watchers etc. are active in both
2946parent and child, which is almost never what you want. USing C<exec>
2947to start worker children from some kind of manage rprocess is usually
2948preferred, because it is much easier and cleaner, at the expense of having
2949to have another binary.
2517 2950
2518 2951
2519=head1 SECURITY CONSIDERATIONS 2952=head1 SECURITY CONSIDERATIONS
2520 2953
2521AnyEvent can be forced to load any event model via 2954AnyEvent can be forced to load any event model via
2551pronounced). 2984pronounced).
2552 2985
2553 2986
2554=head1 SEE ALSO 2987=head1 SEE ALSO
2555 2988
2556Utility functions: L<AnyEvent::Util>. 2989Tutorial/Introduction: L<AnyEvent::Intro>.
2557 2990
2558Event modules: L<EV>, L<EV::Glib>, L<Glib::EV>, L<Event>, L<Glib::Event>, 2991FAQ: L<AnyEvent::FAQ>.
2559L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. 2992
2993Utility functions: L<AnyEvent::Util> (misc. grab-bag), L<AnyEvent::Log>
2994(simply logging).
2995
2996Development/Debugging: L<AnyEvent::Strict> (stricter checking),
2997L<AnyEvent::Debug> (interactive shell, watcher tracing).
2998
2999Supported event modules: L<AnyEvent::Loop>, L<EV>, L<EV::Glib>,
3000L<Glib::EV>, L<Event>, L<Glib::Event>, L<Glib>, L<Tk>, L<Event::Lib>,
3001L<Qt>, L<POE>, L<FLTK>.
2560 3002
2561Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>, 3003Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,
2562L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>, 3004L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,
2563L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>, 3005L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,
2564L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>. 3006L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>,
3007L<AnyEvent::Impl::FLTK>.
2565 3008
2566Non-blocking file handles, sockets, TCP clients and 3009Non-blocking handles, pipes, stream sockets, TCP clients and
2567servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>. 3010servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.
2568 3011
2569Asynchronous DNS: L<AnyEvent::DNS>. 3012Asynchronous DNS: L<AnyEvent::DNS>.
2570 3013
2571Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, 3014Thread support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>.
2572L<Coro::Event>,
2573 3015
2574Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::XMPP>, 3016Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::IRC>,
2575L<AnyEvent::HTTP>. 3017L<AnyEvent::HTTP>.
2576 3018
2577 3019
2578=head1 AUTHOR 3020=head1 AUTHOR
2579 3021

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