… | |
… | |
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 L<AE> manpage for |
12 | # if you prefer function calls, look at the AE manpage for |
13 | # an alternative API. |
13 | # an alternative API. |
14 | |
14 | |
15 | # file handle or descriptor readable |
15 | # file handle or descriptor readable |
16 | my $w = AnyEvent->io (fh => $fh, poll => "r", cb => sub { ... }); |
16 | my $w = AnyEvent->io (fh => $fh, poll => "r", cb => sub { ... }); |
17 | |
17 | |
18 | # one-shot or repeating timers |
18 | # one-shot or repeating timers |
19 | my $w = AnyEvent->timer (after => $seconds, cb => sub { ... }); |
19 | my $w = AnyEvent->timer (after => $seconds, cb => sub { ... }); |
20 | my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ... |
20 | my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ...); |
21 | |
21 | |
22 | print AnyEvent->now; # prints current event loop time |
22 | print AnyEvent->now; # prints current event loop time |
23 | print AnyEvent->time; # think Time::HiRes::time or simply CORE::time. |
23 | print AnyEvent->time; # think Time::HiRes::time or simply CORE::time. |
24 | |
24 | |
25 | # POSIX signal |
25 | # POSIX signal |
… | |
… | |
46 | in a tutorial or some gentle introduction, have a look at the |
46 | in a tutorial or some gentle introduction, have a look at the |
47 | L<AnyEvent::Intro> manpage. |
47 | L<AnyEvent::Intro> manpage. |
48 | |
48 | |
49 | =head1 SUPPORT |
49 | =head1 SUPPORT |
50 | |
50 | |
|
|
51 | An FAQ document is available as L<AnyEvent::FAQ>. |
|
|
52 | |
51 | There is a mailinglist for discussing all things AnyEvent, and an IRC |
53 | There also is a mailinglist for discussing all things AnyEvent, and an IRC |
52 | channel, too. |
54 | channel, too. |
53 | |
55 | |
54 | See the AnyEvent project page at the B<Schmorpforge Ta-Sa Software |
56 | See the AnyEvent project page at the B<Schmorpforge Ta-Sa Software |
55 | Repository>, at L<http://anyevent.schmorp.de>, for more info. |
57 | Repository>, at L<http://anyevent.schmorp.de>, for more info. |
56 | |
58 | |
… | |
… | |
76 | module users into the same thing by forcing them to use the same event |
78 | module users into the same thing by forcing them to use the same event |
77 | model you use. |
79 | model you use. |
78 | |
80 | |
79 | For modules like POE or IO::Async (which is a total misnomer as it is |
81 | For modules like POE or IO::Async (which is a total misnomer as it is |
80 | actually doing all I/O I<synchronously>...), using them in your module is |
82 | actually doing all I/O I<synchronously>...), using them in your module is |
81 | like joining a cult: After you joined, you are dependent on them and you |
83 | like joining a cult: After you join, you are dependent on them and you |
82 | cannot use anything else, as they are simply incompatible to everything |
84 | cannot use anything else, as they are simply incompatible to everything |
83 | that isn't them. What's worse, all the potential users of your |
85 | that isn't them. What's worse, all the potential users of your |
84 | module are I<also> forced to use the same event loop you use. |
86 | module are I<also> forced to use the same event loop you use. |
85 | |
87 | |
86 | AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works |
88 | AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works |
87 | fine. AnyEvent + Tk works fine etc. etc. but none of these work together |
89 | fine. AnyEvent + Tk works fine etc. etc. but none of these work together |
88 | with the rest: POE + IO::Async? No go. Tk + Event? No go. Again: if |
90 | with the rest: POE + EV? No go. Tk + Event? No go. Again: if your module |
89 | your module uses one of those, every user of your module has to use it, |
91 | uses one of those, every user of your module has to use it, too. But if |
90 | too. But if your module uses AnyEvent, it works transparently with all |
92 | your module uses AnyEvent, it works transparently with all event models it |
91 | event models it supports (including stuff like IO::Async, as long as those |
93 | supports (including stuff like IO::Async, as long as those use one of the |
92 | use one of the supported event loops. It is trivial to add new event loops |
94 | supported event loops. It is easy to add new event loops to AnyEvent, too, |
93 | to AnyEvent, too, so it is future-proof). |
95 | so it is future-proof). |
94 | |
96 | |
95 | In addition to being free of having to use I<the one and only true event |
97 | In addition to being free of having to use I<the one and only true event |
96 | model>, AnyEvent also is free of bloat and policy: with POE or similar |
98 | model>, AnyEvent also is free of bloat and policy: with POE or similar |
97 | modules, you get an enormous amount of code and strict rules you have to |
99 | modules, you get an enormous amount of code and strict rules you have to |
98 | follow. AnyEvent, on the other hand, is lean and up to the point, by only |
100 | follow. AnyEvent, on the other hand, is lean and to the point, by only |
99 | offering the functionality that is necessary, in as thin as a wrapper as |
101 | offering the functionality that is necessary, in as thin as a wrapper as |
100 | technically possible. |
102 | technically possible. |
101 | |
103 | |
102 | Of course, AnyEvent comes with a big (and fully optional!) toolbox |
104 | Of course, AnyEvent comes with a big (and fully optional!) toolbox |
103 | of useful functionality, such as an asynchronous DNS resolver, 100% |
105 | of useful functionality, such as an asynchronous DNS resolver, 100% |
… | |
… | |
109 | useful) and you want to force your users to use the one and only event |
111 | useful) and you want to force your users to use the one and only event |
110 | model, you should I<not> use this module. |
112 | model, you should I<not> use this module. |
111 | |
113 | |
112 | =head1 DESCRIPTION |
114 | =head1 DESCRIPTION |
113 | |
115 | |
114 | L<AnyEvent> provides an identical interface to multiple event loops. This |
116 | L<AnyEvent> provides a uniform interface to various event loops. This |
115 | allows module authors to utilise an event loop without forcing module |
117 | allows module authors to use event loop functionality without forcing |
116 | users to use the same event loop (as only a single event loop can coexist |
118 | module users to use a specific event loop implementation (since more |
117 | peacefully at any one time). |
119 | than one event loop cannot coexist peacefully). |
118 | |
120 | |
119 | The interface itself is vaguely similar, but not identical to the L<Event> |
121 | The interface itself is vaguely similar, but not identical to the L<Event> |
120 | module. |
122 | module. |
121 | |
123 | |
122 | During the first call of any watcher-creation method, the module tries |
124 | During the first call of any watcher-creation method, the module tries |
123 | to detect the currently loaded event loop by probing whether one of the |
125 | to detect the currently loaded event loop by probing whether one of the |
124 | following modules is already loaded: L<EV>, |
126 | following modules is already loaded: L<EV>, L<AnyEvent::Impl::Perl>, |
125 | L<Event>, L<Glib>, L<AnyEvent::Impl::Perl>, L<Tk>, L<Event::Lib>, L<Qt>, |
127 | L<Event>, L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. The first one |
126 | L<POE>. The first one found is used. If none are found, the module tries |
128 | found is used. If none are detected, the module tries to load the first |
127 | to load these modules (excluding Tk, Event::Lib, Qt and POE as the pure perl |
129 | four modules in the order given; but note that if L<EV> is not |
128 | adaptor should always succeed) in the order given. The first one that can |
130 | available, the pure-perl L<AnyEvent::Impl::Perl> should always work, so |
129 | be successfully loaded will be used. If, after this, still none could be |
131 | the other two are not normally tried. |
130 | found, AnyEvent will fall back to a pure-perl event loop, which is not |
|
|
131 | very efficient, but should work everywhere. |
|
|
132 | |
132 | |
133 | Because AnyEvent first checks for modules that are already loaded, loading |
133 | Because AnyEvent first checks for modules that are already loaded, loading |
134 | an event model explicitly before first using AnyEvent will likely make |
134 | an event model explicitly before first using AnyEvent will likely make |
135 | that model the default. For example: |
135 | that model the default. For example: |
136 | |
136 | |
… | |
… | |
138 | use AnyEvent; |
138 | use AnyEvent; |
139 | |
139 | |
140 | # .. AnyEvent will likely default to Tk |
140 | # .. AnyEvent will likely default to Tk |
141 | |
141 | |
142 | The I<likely> means that, if any module loads another event model and |
142 | The I<likely> means that, if any module loads another event model and |
143 | starts using it, all bets are off. Maybe you should tell their authors to |
143 | starts using it, all bets are off - this case should be very rare though, |
144 | use AnyEvent so their modules work together with others seamlessly... |
144 | as very few modules hardcode event loops without announcing this very |
|
|
145 | loudly. |
145 | |
146 | |
146 | The pure-perl implementation of AnyEvent is called |
147 | The pure-perl implementation of AnyEvent is called |
147 | C<AnyEvent::Impl::Perl>. Like other event modules you can load it |
148 | C<AnyEvent::Impl::Perl>. Like other event modules you can load it |
148 | explicitly and enjoy the high availability of that event loop :) |
149 | explicitly and enjoy the high availability of that event loop :) |
149 | |
150 | |
… | |
… | |
158 | callback when the event occurs (of course, only when the event model |
159 | callback when the event occurs (of course, only when the event model |
159 | is in control). |
160 | is in control). |
160 | |
161 | |
161 | Note that B<callbacks must not permanently change global variables> |
162 | Note that B<callbacks must not permanently change global variables> |
162 | potentially in use by the event loop (such as C<$_> or C<$[>) and that B<< |
163 | potentially in use by the event loop (such as C<$_> or C<$[>) and that B<< |
163 | callbacks must not C<die> >>. The former is good programming practise in |
164 | callbacks must not C<die> >>. The former is good programming practice in |
164 | Perl and the latter stems from the fact that exception handling differs |
165 | Perl and the latter stems from the fact that exception handling differs |
165 | widely between event loops. |
166 | widely between event loops. |
166 | |
167 | |
167 | To disable the watcher you have to destroy it (e.g. by setting the |
168 | To disable a watcher you have to destroy it (e.g. by setting the |
168 | variable you store it in to C<undef> or otherwise deleting all references |
169 | variable you store it in to C<undef> or otherwise deleting all references |
169 | to it). |
170 | to it). |
170 | |
171 | |
171 | All watchers are created by calling a method on the C<AnyEvent> class. |
172 | All watchers are created by calling a method on the C<AnyEvent> class. |
172 | |
173 | |
173 | Many watchers either are used with "recursion" (repeating timers for |
174 | Many watchers either are used with "recursion" (repeating timers for |
174 | example), or need to refer to their watcher object in other ways. |
175 | example), or need to refer to their watcher object in other ways. |
175 | |
176 | |
176 | An any way to achieve that is this pattern: |
177 | One way to achieve that is this pattern: |
177 | |
178 | |
178 | my $w; $w = AnyEvent->type (arg => value ..., cb => sub { |
179 | my $w; $w = AnyEvent->type (arg => value ..., cb => sub { |
179 | # you can use $w here, for example to undef it |
180 | # you can use $w here, for example to undef it |
180 | undef $w; |
181 | undef $w; |
181 | }); |
182 | }); |
… | |
… | |
213 | |
214 | |
214 | The I/O watcher might use the underlying file descriptor or a copy of it. |
215 | The I/O watcher might use the underlying file descriptor or a copy of it. |
215 | You must not close a file handle as long as any watcher is active on the |
216 | You must not close a file handle as long as any watcher is active on the |
216 | underlying file descriptor. |
217 | underlying file descriptor. |
217 | |
218 | |
218 | Some event loops issue spurious readyness notifications, so you should |
219 | Some event loops issue spurious readiness notifications, so you should |
219 | always use non-blocking calls when reading/writing from/to your file |
220 | always use non-blocking calls when reading/writing from/to your file |
220 | handles. |
221 | handles. |
221 | |
222 | |
222 | Example: wait for readability of STDIN, then read a line and disable the |
223 | Example: wait for readability of STDIN, then read a line and disable the |
223 | watcher. |
224 | watcher. |
… | |
… | |
247 | |
248 | |
248 | Although the callback might get passed parameters, their value and |
249 | Although the callback might get passed parameters, their value and |
249 | presence is undefined and you cannot rely on them. Portable AnyEvent |
250 | presence is undefined and you cannot rely on them. Portable AnyEvent |
250 | callbacks cannot use arguments passed to time watcher callbacks. |
251 | callbacks cannot use arguments passed to time watcher callbacks. |
251 | |
252 | |
252 | The callback will normally be invoked once only. If you specify another |
253 | The callback will normally be invoked only once. If you specify another |
253 | parameter, C<interval>, as a strictly positive number (> 0), then the |
254 | parameter, C<interval>, as a strictly positive number (> 0), then the |
254 | callback will be invoked regularly at that interval (in fractional |
255 | callback will be invoked regularly at that interval (in fractional |
255 | seconds) after the first invocation. If C<interval> is specified with a |
256 | seconds) after the first invocation. If C<interval> is specified with a |
256 | false value, then it is treated as if it were missing. |
257 | false value, then it is treated as if it were not specified at all. |
257 | |
258 | |
258 | The callback will be rescheduled before invoking the callback, but no |
259 | The callback will be rescheduled before invoking the callback, but no |
259 | attempt is done to avoid timer drift in most backends, so the interval is |
260 | attempt is made to avoid timer drift in most backends, so the interval is |
260 | only approximate. |
261 | only approximate. |
261 | |
262 | |
262 | Example: fire an event after 7.7 seconds. |
263 | Example: fire an event after 7.7 seconds. |
263 | |
264 | |
264 | my $w = AnyEvent->timer (after => 7.7, cb => sub { |
265 | my $w = AnyEvent->timer (after => 7.7, cb => sub { |
… | |
… | |
282 | |
283 | |
283 | While most event loops expect timers to specified in a relative way, they |
284 | While most event loops expect timers to specified in a relative way, they |
284 | use absolute time internally. This makes a difference when your clock |
285 | use absolute time internally. This makes a difference when your clock |
285 | "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 |
286 | the wrong date of 2014-01-01 to 2008-01-01, a watcher that is supposed to |
287 | the wrong date of 2014-01-01 to 2008-01-01, a watcher that is supposed to |
287 | fire "after" a second might actually take six years to finally fire. |
288 | fire "after a second" might actually take six years to finally fire. |
288 | |
289 | |
289 | AnyEvent cannot compensate for this. The only event loop that is conscious |
290 | AnyEvent cannot compensate for this. The only event loop that is conscious |
290 | about these issues is L<EV>, which offers both relative (ev_timer, based |
291 | of these issues is L<EV>, which offers both relative (ev_timer, based |
291 | on true relative time) and absolute (ev_periodic, based on wallclock time) |
292 | on true relative time) and absolute (ev_periodic, based on wallclock time) |
292 | timers. |
293 | timers. |
293 | |
294 | |
294 | AnyEvent always prefers relative timers, if available, matching the |
295 | AnyEvent always prefers relative timers, if available, matching the |
295 | AnyEvent API. |
296 | AnyEvent API. |
… | |
… | |
317 | I<In almost all cases (in all cases if you don't care), this is the |
318 | I<In almost all cases (in all cases if you don't care), this is the |
318 | function to call when you want to know the current time.> |
319 | function to call when you want to know the current time.> |
319 | |
320 | |
320 | This function is also often faster then C<< AnyEvent->time >>, and |
321 | This function is also often faster then C<< AnyEvent->time >>, and |
321 | thus the preferred method if you want some timestamp (for example, |
322 | thus the preferred method if you want some timestamp (for example, |
322 | L<AnyEvent::Handle> uses this to update it's activity timeouts). |
323 | L<AnyEvent::Handle> uses this to update its activity timeouts). |
323 | |
324 | |
324 | The rest of this section is only of relevance if you try to be very exact |
325 | The rest of this section is only of relevance if you try to be very exact |
325 | with your timing, you can skip it without bad conscience. |
326 | with your timing; you can skip it without a bad conscience. |
326 | |
327 | |
327 | For a practical example of when these times differ, consider L<Event::Lib> |
328 | For a practical example of when these times differ, consider L<Event::Lib> |
328 | and L<EV> and the following set-up: |
329 | and L<EV> and the following set-up: |
329 | |
330 | |
330 | The event loop is running and has just invoked one of your callback at |
331 | The event loop is running and has just invoked one of your callbacks at |
331 | time=500 (assume no other callbacks delay processing). In your callback, |
332 | time=500 (assume no other callbacks delay processing). In your callback, |
332 | you wait a second by executing C<sleep 1> (blocking the process for a |
333 | you wait a second by executing C<sleep 1> (blocking the process for a |
333 | second) and then (at time=501) you create a relative timer that fires |
334 | second) and then (at time=501) you create a relative timer that fires |
334 | after three seconds. |
335 | after three seconds. |
335 | |
336 | |
… | |
… | |
428 | =head3 Signal Races, Delays and Workarounds |
429 | =head3 Signal Races, Delays and Workarounds |
429 | |
430 | |
430 | Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching |
431 | Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching |
431 | callbacks to signals in a generic way, which is a pity, as you cannot |
432 | callbacks to signals in a generic way, which is a pity, as you cannot |
432 | do race-free signal handling in perl, requiring C libraries for |
433 | do race-free signal handling in perl, requiring C libraries for |
433 | this. AnyEvent will try to do it's best, which means in some cases, |
434 | this. AnyEvent will try to do its best, which means in some cases, |
434 | signals will be delayed. The maximum time a signal might be delayed is |
435 | signals will be delayed. The maximum time a signal might be delayed is |
435 | specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This |
436 | specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This |
436 | variable can be changed only before the first signal watcher is created, |
437 | variable can be changed only before the first signal watcher is created, |
437 | and should be left alone otherwise. This variable determines how often |
438 | and should be left alone otherwise. This variable determines how often |
438 | AnyEvent polls for signals (in case a wake-up was missed). Higher values |
439 | AnyEvent polls for signals (in case a wake-up was missed). Higher values |
… | |
… | |
440 | saving. |
441 | saving. |
441 | |
442 | |
442 | All these problems can be avoided by installing the optional |
443 | All these problems can be avoided by installing the optional |
443 | L<Async::Interrupt> module, which works with most event loops. It will not |
444 | L<Async::Interrupt> module, which works with most event loops. It will not |
444 | work with inherently broken event loops such as L<Event> or L<Event::Lib> |
445 | work with inherently broken event loops such as L<Event> or L<Event::Lib> |
445 | (and not with L<POE> currently, as POE does it's own workaround with |
446 | (and not with L<POE> currently, as POE does its own workaround with |
446 | one-second latency). For those, you just have to suffer the delays. |
447 | one-second latency). For those, you just have to suffer the delays. |
447 | |
448 | |
448 | =head2 CHILD PROCESS WATCHERS |
449 | =head2 CHILD PROCESS WATCHERS |
449 | |
450 | |
450 | $w = AnyEvent->child (pid => <process id>, cb => <callback>); |
451 | $w = AnyEvent->child (pid => <process id>, cb => <callback>); |
451 | |
452 | |
452 | You can also watch on a child process exit and catch its exit status. |
453 | You can also watch for a child process exit and catch its exit status. |
453 | |
454 | |
454 | The child process is specified by the C<pid> argument (one some backends, |
455 | The child process is specified by the C<pid> argument (on some backends, |
455 | using C<0> watches for any child process exit, on others this will |
456 | using C<0> watches for any child process exit, on others this will |
456 | croak). The watcher will be triggered only when the child process has |
457 | croak). The watcher will be triggered only when the child process has |
457 | finished and an exit status is available, not on any trace events |
458 | finished and an exit status is available, not on any trace events |
458 | (stopped/continued). |
459 | (stopped/continued). |
459 | |
460 | |
… | |
… | |
506 | |
507 | |
507 | =head2 IDLE WATCHERS |
508 | =head2 IDLE WATCHERS |
508 | |
509 | |
509 | $w = AnyEvent->idle (cb => <callback>); |
510 | $w = AnyEvent->idle (cb => <callback>); |
510 | |
511 | |
511 | Repeatedly invoke the callback after the process becomes idle, until |
512 | This will repeatedly invoke the callback after the process becomes idle, |
512 | either the watcher is destroyed or new events have been detected. |
513 | until either the watcher is destroyed or new events have been detected. |
513 | |
514 | |
514 | Idle watchers are useful when there is a need to do something, but it |
515 | Idle watchers are useful when there is a need to do something, but it |
515 | is not so important (or wise) to do it instantly. The callback will be |
516 | is not so important (or wise) to do it instantly. The callback will be |
516 | invoked only when there is "nothing better to do", which is usually |
517 | invoked only when there is "nothing better to do", which is usually |
517 | defined as "all outstanding events have been handled and no new events |
518 | defined as "all outstanding events have been handled and no new events |
… | |
… | |
556 | will actively watch for new events and call your callbacks. |
557 | will actively watch for new events and call your callbacks. |
557 | |
558 | |
558 | AnyEvent is slightly different: it expects somebody else to run the event |
559 | AnyEvent is slightly different: it expects somebody else to run the event |
559 | loop and will only block when necessary (usually when told by the user). |
560 | loop and will only block when necessary (usually when told by the user). |
560 | |
561 | |
561 | The instrument to do that is called a "condition variable", so called |
562 | The tool to do that is called a "condition variable", so called because |
562 | because they represent a condition that must become true. |
563 | they represent a condition that must become true. |
563 | |
564 | |
564 | Now is probably a good time to look at the examples further below. |
565 | Now is probably a good time to look at the examples further below. |
565 | |
566 | |
566 | Condition variables can be created by calling the C<< AnyEvent->condvar |
567 | Condition variables can be created by calling the C<< AnyEvent->condvar |
567 | >> method, usually without arguments. The only argument pair allowed is |
568 | >> method, usually without arguments. The only argument pair allowed is |
… | |
… | |
572 | After creation, the condition variable is "false" until it becomes "true" |
573 | After creation, the condition variable is "false" until it becomes "true" |
573 | by calling the C<send> method (or calling the condition variable as if it |
574 | by calling the C<send> method (or calling the condition variable as if it |
574 | were a callback, read about the caveats in the description for the C<< |
575 | were a callback, read about the caveats in the description for the C<< |
575 | ->send >> method). |
576 | ->send >> method). |
576 | |
577 | |
577 | Condition variables are similar to callbacks, except that you can |
578 | Since condition variables are the most complex part of the AnyEvent API, here are |
578 | optionally wait for them. They can also be called merge points - points |
579 | some different mental models of what they are - pick the ones you can connect to: |
579 | in time where multiple outstanding events have been processed. And yet |
580 | |
580 | another way to call them is transactions - each condition variable can be |
581 | =over 4 |
581 | used to represent a transaction, which finishes at some point and delivers |
582 | |
582 | a result. And yet some people know them as "futures" - a promise to |
583 | =item * Condition variables are like callbacks - you can call them (and pass them instead |
583 | compute/deliver something that you can wait for. |
584 | of callbacks). Unlike callbacks however, you can also wait for them to be called. |
|
|
585 | |
|
|
586 | =item * Condition variables are signals - one side can emit or send them, |
|
|
587 | the other side can wait for them, or install a handler that is called when |
|
|
588 | the signal fires. |
|
|
589 | |
|
|
590 | =item * Condition variables are like "Merge Points" - points in your program |
|
|
591 | where you merge multiple independent results/control flows into one. |
|
|
592 | |
|
|
593 | =item * Condition variables represent a transaction - functions that start |
|
|
594 | some kind of transaction can return them, leaving the caller the choice |
|
|
595 | between waiting in a blocking fashion, or setting a callback. |
|
|
596 | |
|
|
597 | =item * Condition variables represent future values, or promises to deliver |
|
|
598 | some result, long before the result is available. |
|
|
599 | |
|
|
600 | =back |
584 | |
601 | |
585 | Condition variables are very useful to signal that something has finished, |
602 | Condition variables are very useful to signal that something has finished, |
586 | for example, if you write a module that does asynchronous http requests, |
603 | for example, if you write a module that does asynchronous http requests, |
587 | then a condition variable would be the ideal candidate to signal the |
604 | then a condition variable would be the ideal candidate to signal the |
588 | availability of results. The user can either act when the callback is |
605 | availability of results. The user can either act when the callback is |
… | |
… | |
601 | |
618 | |
602 | Condition variables are represented by hash refs in perl, and the keys |
619 | Condition variables are represented by hash refs in perl, and the keys |
603 | used by AnyEvent itself are all named C<_ae_XXX> to make subclassing |
620 | used by AnyEvent itself are all named C<_ae_XXX> to make subclassing |
604 | easy (it is often useful to build your own transaction class on top of |
621 | easy (it is often useful to build your own transaction class on top of |
605 | AnyEvent). To subclass, use C<AnyEvent::CondVar> as base class and call |
622 | AnyEvent). To subclass, use C<AnyEvent::CondVar> as base class and call |
606 | it's C<new> method in your own C<new> method. |
623 | its C<new> method in your own C<new> method. |
607 | |
624 | |
608 | There are two "sides" to a condition variable - the "producer side" which |
625 | There are two "sides" to a condition variable - the "producer side" which |
609 | eventually calls C<< -> send >>, and the "consumer side", which waits |
626 | eventually calls C<< -> send >>, and the "consumer side", which waits |
610 | for the send to occur. |
627 | for the send to occur. |
611 | |
628 | |
612 | Example: wait for a timer. |
629 | Example: wait for a timer. |
613 | |
630 | |
614 | # wait till the result is ready |
631 | # condition: "wait till the timer is fired" |
615 | my $result_ready = AnyEvent->condvar; |
632 | my $timer_fired = AnyEvent->condvar; |
616 | |
633 | |
617 | # do something such as adding a timer |
634 | # create the timer - we could wait for, say |
618 | # or socket watcher the calls $result_ready->send |
635 | # a handle becomign ready, or even an |
619 | # when the "result" is ready. |
636 | # AnyEvent::HTTP request to finish, but |
620 | # in this case, we simply use a timer: |
637 | # in this case, we simply use a timer: |
621 | my $w = AnyEvent->timer ( |
638 | my $w = AnyEvent->timer ( |
622 | after => 1, |
639 | after => 1, |
623 | cb => sub { $result_ready->send }, |
640 | cb => sub { $timer_fired->send }, |
624 | ); |
641 | ); |
625 | |
642 | |
626 | # this "blocks" (while handling events) till the callback |
643 | # this "blocks" (while handling events) till the callback |
627 | # calls ->send |
644 | # calls ->send |
628 | $result_ready->recv; |
645 | $timer_fired->recv; |
629 | |
646 | |
630 | Example: wait for a timer, but take advantage of the fact that condition |
647 | Example: wait for a timer, but take advantage of the fact that condition |
631 | variables are also callable directly. |
648 | variables are also callable directly. |
632 | |
649 | |
633 | my $done = AnyEvent->condvar; |
650 | my $done = AnyEvent->condvar; |
… | |
… | |
676 | they were a code reference). Calling them directly is the same as calling |
693 | they were a code reference). Calling them directly is the same as calling |
677 | C<send>. |
694 | C<send>. |
678 | |
695 | |
679 | =item $cv->croak ($error) |
696 | =item $cv->croak ($error) |
680 | |
697 | |
681 | Similar to send, but causes all call's to C<< ->recv >> to invoke |
698 | Similar to send, but causes all calls to C<< ->recv >> to invoke |
682 | C<Carp::croak> with the given error message/object/scalar. |
699 | C<Carp::croak> with the given error message/object/scalar. |
683 | |
700 | |
684 | This can be used to signal any errors to the condition variable |
701 | This can be used to signal any errors to the condition variable |
685 | user/consumer. Doing it this way instead of calling C<croak> directly |
702 | user/consumer. Doing it this way instead of calling C<croak> directly |
686 | delays the error detetcion, but has the overwhelmign advantage that it |
703 | delays the error detection, but has the overwhelming advantage that it |
687 | diagnoses the error at the place where the result is expected, and not |
704 | diagnoses the error at the place where the result is expected, and not |
688 | deep in some event clalback without connection to the actual code causing |
705 | deep in some event callback with no connection to the actual code causing |
689 | the problem. |
706 | the problem. |
690 | |
707 | |
691 | =item $cv->begin ([group callback]) |
708 | =item $cv->begin ([group callback]) |
692 | |
709 | |
693 | =item $cv->end |
710 | =item $cv->end |
… | |
… | |
731 | one call to C<begin>, so the condvar waits for all calls to C<end> before |
748 | one call to C<begin>, so the condvar waits for all calls to C<end> before |
732 | sending. |
749 | sending. |
733 | |
750 | |
734 | The ping example mentioned above is slightly more complicated, as the |
751 | The ping example mentioned above is slightly more complicated, as the |
735 | there are results to be passwd back, and the number of tasks that are |
752 | there are results to be passwd back, and the number of tasks that are |
736 | begung can potentially be zero: |
753 | begun can potentially be zero: |
737 | |
754 | |
738 | my $cv = AnyEvent->condvar; |
755 | my $cv = AnyEvent->condvar; |
739 | |
756 | |
740 | my %result; |
757 | my %result; |
741 | $cv->begin (sub { shift->send (\%result) }); |
758 | $cv->begin (sub { shift->send (\%result) }); |
… | |
… | |
762 | to be called once the counter reaches C<0>, and second, it ensures that |
779 | to be called once the counter reaches C<0>, and second, it ensures that |
763 | C<send> is called even when C<no> hosts are being pinged (the loop |
780 | C<send> is called even when C<no> hosts are being pinged (the loop |
764 | doesn't execute once). |
781 | doesn't execute once). |
765 | |
782 | |
766 | This is the general pattern when you "fan out" into multiple (but |
783 | This is the general pattern when you "fan out" into multiple (but |
767 | potentially none) subrequests: use an outer C<begin>/C<end> pair to set |
784 | potentially zero) subrequests: use an outer C<begin>/C<end> pair to set |
768 | the callback and ensure C<end> is called at least once, and then, for each |
785 | the callback and ensure C<end> is called at least once, and then, for each |
769 | subrequest you start, call C<begin> and for each subrequest you finish, |
786 | subrequest you start, call C<begin> and for each subrequest you finish, |
770 | call C<end>. |
787 | call C<end>. |
771 | |
788 | |
772 | =back |
789 | =back |
… | |
… | |
779 | =over 4 |
796 | =over 4 |
780 | |
797 | |
781 | =item $cv->recv |
798 | =item $cv->recv |
782 | |
799 | |
783 | Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak |
800 | Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak |
784 | >> methods have been called on c<$cv>, while servicing other watchers |
801 | >> methods have been called on C<$cv>, while servicing other watchers |
785 | normally. |
802 | normally. |
786 | |
803 | |
787 | You can only wait once on a condition - additional calls are valid but |
804 | You can only wait once on a condition - additional calls are valid but |
788 | will return immediately. |
805 | will return immediately. |
789 | |
806 | |
… | |
… | |
806 | caller decide whether the call will block or not (for example, by coupling |
823 | caller decide whether the call will block or not (for example, by coupling |
807 | condition variables with some kind of request results and supporting |
824 | condition variables with some kind of request results and supporting |
808 | callbacks so the caller knows that getting the result will not block, |
825 | callbacks so the caller knows that getting the result will not block, |
809 | while still supporting blocking waits if the caller so desires). |
826 | while still supporting blocking waits if the caller so desires). |
810 | |
827 | |
811 | You can ensure that C<< -recv >> never blocks by setting a callback and |
828 | You can ensure that C<< ->recv >> never blocks by setting a callback and |
812 | only calling C<< ->recv >> from within that callback (or at a later |
829 | only calling C<< ->recv >> from within that callback (or at a later |
813 | time). This will work even when the event loop does not support blocking |
830 | time). This will work even when the event loop does not support blocking |
814 | waits otherwise. |
831 | waits otherwise. |
815 | |
832 | |
816 | =item $bool = $cv->ready |
833 | =item $bool = $cv->ready |
… | |
… | |
821 | =item $cb = $cv->cb ($cb->($cv)) |
838 | =item $cb = $cv->cb ($cb->($cv)) |
822 | |
839 | |
823 | This is a mutator function that returns the callback set and optionally |
840 | This is a mutator function that returns the callback set and optionally |
824 | replaces it before doing so. |
841 | replaces it before doing so. |
825 | |
842 | |
826 | The callback will be called when the condition becomes (or already was) |
843 | The callback will be called when the condition becomes "true", i.e. when |
827 | "true", i.e. when C<send> or C<croak> are called (or were called), with |
844 | C<send> or C<croak> are called, with the only argument being the |
828 | the only argument being the condition variable itself. Calling C<recv> |
845 | condition variable itself. If the condition is already true, the |
|
|
846 | callback is called immediately when it is set. Calling C<recv> inside |
829 | inside the callback or at any later time is guaranteed not to block. |
847 | the callback or at any later time is guaranteed not to block. |
830 | |
848 | |
831 | =back |
849 | =back |
832 | |
850 | |
833 | =head1 SUPPORTED EVENT LOOPS/BACKENDS |
851 | =head1 SUPPORTED EVENT LOOPS/BACKENDS |
834 | |
852 | |
… | |
… | |
846 | AnyEvent::Impl::EV based on EV (interface to libev, best choice). |
864 | AnyEvent::Impl::EV based on EV (interface to libev, best choice). |
847 | AnyEvent::Impl::Perl pure-perl implementation, fast and portable. |
865 | AnyEvent::Impl::Perl pure-perl implementation, fast and portable. |
848 | |
866 | |
849 | =item Backends that are transparently being picked up when they are used. |
867 | =item Backends that are transparently being picked up when they are used. |
850 | |
868 | |
851 | These will be used when they are currently loaded when the first watcher |
869 | These will be used if they are already loaded when the first watcher |
852 | is created, in which case it is assumed that the application is using |
870 | is created, in which case it is assumed that the application is using |
853 | them. This means that AnyEvent will automatically pick the right backend |
871 | them. This means that AnyEvent will automatically pick the right backend |
854 | when the main program loads an event module before anything starts to |
872 | when the main program loads an event module before anything starts to |
855 | create watchers. Nothing special needs to be done by the main program. |
873 | create watchers. Nothing special needs to be done by the main program. |
856 | |
874 | |
… | |
… | |
858 | AnyEvent::Impl::Glib based on Glib, slow but very stable. |
876 | AnyEvent::Impl::Glib based on Glib, slow but very stable. |
859 | AnyEvent::Impl::Tk based on Tk, very broken. |
877 | AnyEvent::Impl::Tk based on Tk, very broken. |
860 | AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. |
878 | AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. |
861 | AnyEvent::Impl::POE based on POE, very slow, some limitations. |
879 | AnyEvent::Impl::POE based on POE, very slow, some limitations. |
862 | AnyEvent::Impl::Irssi used when running within irssi. |
880 | AnyEvent::Impl::Irssi used when running within irssi. |
|
|
881 | AnyEvent::Impl::IOAsync based on IO::Async. |
|
|
882 | AnyEvent::Impl::Cocoa based on Cocoa::EventLoop. |
|
|
883 | AnyEvent::Impl::FLTK based on FLTK. |
863 | |
884 | |
864 | =item Backends with special needs. |
885 | =item Backends with special needs. |
865 | |
886 | |
866 | Qt requires the Qt::Application to be instantiated first, but will |
887 | Qt requires the Qt::Application to be instantiated first, but will |
867 | otherwise be picked up automatically. As long as the main program |
888 | otherwise be picked up automatically. As long as the main program |
868 | instantiates the application before any AnyEvent watchers are created, |
889 | instantiates the application before any AnyEvent watchers are created, |
869 | everything should just work. |
890 | everything should just work. |
870 | |
891 | |
871 | AnyEvent::Impl::Qt based on Qt. |
892 | AnyEvent::Impl::Qt based on Qt. |
872 | |
893 | |
873 | Support for IO::Async can only be partial, as it is too broken and |
|
|
874 | architecturally limited to even support the AnyEvent API. It also |
|
|
875 | is the only event loop that needs the loop to be set explicitly, so |
|
|
876 | it can only be used by a main program knowing about AnyEvent. See |
|
|
877 | L<AnyEvent::Impl::Async> for the gory details. |
|
|
878 | |
|
|
879 | AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed. |
|
|
880 | |
|
|
881 | =item Event loops that are indirectly supported via other backends. |
894 | =item Event loops that are indirectly supported via other backends. |
882 | |
895 | |
883 | Some event loops can be supported via other modules: |
896 | Some event loops can be supported via other modules: |
884 | |
897 | |
885 | There is no direct support for WxWidgets (L<Wx>) or L<Prima>. |
898 | There is no direct support for WxWidgets (L<Wx>) or L<Prima>. |
… | |
… | |
910 | Contains C<undef> until the first watcher is being created, before the |
923 | Contains C<undef> until the first watcher is being created, before the |
911 | backend has been autodetected. |
924 | backend has been autodetected. |
912 | |
925 | |
913 | Afterwards it contains the event model that is being used, which is the |
926 | Afterwards it contains the event model that is being used, which is the |
914 | name of the Perl class implementing the model. This class is usually one |
927 | name of the Perl class implementing the model. This class is usually one |
915 | of the C<AnyEvent::Impl:xxx> modules, but can be any other class in the |
928 | of the C<AnyEvent::Impl::xxx> modules, but can be any other class in the |
916 | case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it |
929 | case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it |
917 | will be C<urxvt::anyevent>). |
930 | will be C<urxvt::anyevent>). |
918 | |
931 | |
919 | =item AnyEvent::detect |
932 | =item AnyEvent::detect |
920 | |
933 | |
921 | Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model |
934 | Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model |
922 | if necessary. You should only call this function right before you would |
935 | if necessary. You should only call this function right before you would |
923 | have created an AnyEvent watcher anyway, that is, as late as possible at |
936 | have created an AnyEvent watcher anyway, that is, as late as possible at |
924 | runtime, and not e.g. while initialising of your module. |
937 | runtime, and not e.g. during initialisation of your module. |
925 | |
938 | |
926 | If you need to do some initialisation before AnyEvent watchers are |
939 | If you need to do some initialisation before AnyEvent watchers are |
927 | created, use C<post_detect>. |
940 | created, use C<post_detect>. |
928 | |
941 | |
929 | =item $guard = AnyEvent::post_detect { BLOCK } |
942 | =item $guard = AnyEvent::post_detect { BLOCK } |
930 | |
943 | |
931 | Arranges for the code block to be executed as soon as the event model is |
944 | Arranges for the code block to be executed as soon as the event model is |
932 | autodetected (or immediately if this has already happened). |
945 | autodetected (or immediately if that has already happened). |
933 | |
946 | |
934 | The block will be executed I<after> the actual backend has been detected |
947 | The block will be executed I<after> the actual backend has been detected |
935 | (C<$AnyEvent::MODEL> is set), but I<before> any watchers have been |
948 | (C<$AnyEvent::MODEL> is set), but I<before> any watchers have been |
936 | created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do |
949 | created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do |
937 | other initialisations - see the sources of L<AnyEvent::Strict> or |
950 | other initialisations - see the sources of L<AnyEvent::Strict> or |
… | |
… | |
946 | that automatically removes the callback again when it is destroyed (or |
959 | that automatically removes the callback again when it is destroyed (or |
947 | C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for |
960 | C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for |
948 | a case where this is useful. |
961 | a case where this is useful. |
949 | |
962 | |
950 | Example: Create a watcher for the IO::AIO module and store it in |
963 | Example: Create a watcher for the IO::AIO module and store it in |
951 | C<$WATCHER>. Only do so after the event loop is initialised, though. |
964 | C<$WATCHER>, but do so only do so after the event loop is initialised. |
952 | |
965 | |
953 | our WATCHER; |
966 | our WATCHER; |
954 | |
967 | |
955 | my $guard = AnyEvent::post_detect { |
968 | my $guard = AnyEvent::post_detect { |
956 | $WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb); |
969 | $WATCHER = AnyEvent->io (fh => IO::AIO::poll_fileno, poll => 'r', cb => \&IO::AIO::poll_cb); |
… | |
… | |
964 | $WATCHER ||= $guard; |
977 | $WATCHER ||= $guard; |
965 | |
978 | |
966 | =item @AnyEvent::post_detect |
979 | =item @AnyEvent::post_detect |
967 | |
980 | |
968 | If there are any code references in this array (you can C<push> to it |
981 | If there are any code references in this array (you can C<push> to it |
969 | before or after loading AnyEvent), then they will called directly after |
982 | before or after loading AnyEvent), then they will be called directly |
970 | the event loop has been chosen. |
983 | after the event loop has been chosen. |
971 | |
984 | |
972 | You should check C<$AnyEvent::MODEL> before adding to this array, though: |
985 | You should check C<$AnyEvent::MODEL> before adding to this array, though: |
973 | if it is defined then the event loop has already been detected, and the |
986 | if it is defined then the event loop has already been detected, and the |
974 | array will be ignored. |
987 | array will be ignored. |
975 | |
988 | |
… | |
… | |
1011 | because it will stall the whole program, and the whole point of using |
1024 | because it will stall the whole program, and the whole point of using |
1012 | events is to stay interactive. |
1025 | events is to stay interactive. |
1013 | |
1026 | |
1014 | It is fine, however, to call C<< ->recv >> when the user of your module |
1027 | It is fine, however, to call C<< ->recv >> when the user of your module |
1015 | requests it (i.e. if you create a http request object ad have a method |
1028 | requests it (i.e. if you create a http request object ad have a method |
1016 | called C<results> that returns the results, it should call C<< ->recv >> |
1029 | called C<results> that returns the results, it may call C<< ->recv >> |
1017 | freely, as the user of your module knows what she is doing. always). |
1030 | freely, as the user of your module knows what she is doing. Always). |
1018 | |
1031 | |
1019 | =head1 WHAT TO DO IN THE MAIN PROGRAM |
1032 | =head1 WHAT TO DO IN THE MAIN PROGRAM |
1020 | |
1033 | |
1021 | There will always be a single main program - the only place that should |
1034 | There will always be a single main program - the only place that should |
1022 | dictate which event model to use. |
1035 | dictate which event model to use. |
1023 | |
1036 | |
1024 | If it doesn't care, it can just "use AnyEvent" and use it itself, or not |
1037 | If the program is not event-based, it need not do anything special, even |
1025 | do anything special (it does not need to be event-based) and let AnyEvent |
1038 | when it depends on a module that uses an AnyEvent. If the program itself |
1026 | decide which implementation to chose if some module relies on it. |
1039 | uses AnyEvent, but does not care which event loop is used, all it needs |
|
|
1040 | to do is C<use AnyEvent>. In either case, AnyEvent will choose the best |
|
|
1041 | available loop implementation. |
1027 | |
1042 | |
1028 | If the main program relies on a specific event model - for example, in |
1043 | If the main program relies on a specific event model - for example, in |
1029 | Gtk2 programs you have to rely on the Glib module - you should load the |
1044 | Gtk2 programs you have to rely on the Glib module - you should load the |
1030 | event module before loading AnyEvent or any module that uses it: generally |
1045 | event module before loading AnyEvent or any module that uses it: generally |
1031 | speaking, you should load it as early as possible. The reason is that |
1046 | speaking, you should load it as early as possible. The reason is that |
1032 | modules might create watchers when they are loaded, and AnyEvent will |
1047 | modules might create watchers when they are loaded, and AnyEvent will |
1033 | decide on the event model to use as soon as it creates watchers, and it |
1048 | decide on the event model to use as soon as it creates watchers, and it |
1034 | might chose the wrong one unless you load the correct one yourself. |
1049 | might choose the wrong one unless you load the correct one yourself. |
1035 | |
1050 | |
1036 | You can chose to use a pure-perl implementation by loading the |
1051 | You can chose to use a pure-perl implementation by loading the |
1037 | C<AnyEvent::Impl::Perl> module, which gives you similar behaviour |
1052 | C<AnyEvent::Impl::Perl> module, which gives you similar behaviour |
1038 | everywhere, but letting AnyEvent chose the model is generally better. |
1053 | everywhere, but letting AnyEvent chose the model is generally better. |
1039 | |
1054 | |
… | |
… | |
1057 | =head1 OTHER MODULES |
1072 | =head1 OTHER MODULES |
1058 | |
1073 | |
1059 | The following is a non-exhaustive list of additional modules that use |
1074 | The following is a non-exhaustive list of additional modules that use |
1060 | AnyEvent as a client and can therefore be mixed easily with other AnyEvent |
1075 | AnyEvent as a client and can therefore be mixed easily with other AnyEvent |
1061 | modules and other event loops in the same program. Some of the modules |
1076 | modules and other event loops in the same program. Some of the modules |
1062 | come with AnyEvent, most are available via CPAN. |
1077 | come as part of AnyEvent, the others are available via CPAN. |
1063 | |
1078 | |
1064 | =over 4 |
1079 | =over 4 |
1065 | |
1080 | |
1066 | =item L<AnyEvent::Util> |
1081 | =item L<AnyEvent::Util> |
1067 | |
1082 | |
1068 | Contains various utility functions that replace often-used but blocking |
1083 | Contains various utility functions that replace often-used blocking |
1069 | functions such as C<inet_aton> by event-/callback-based versions. |
1084 | functions such as C<inet_aton> with event/callback-based versions. |
1070 | |
1085 | |
1071 | =item L<AnyEvent::Socket> |
1086 | =item L<AnyEvent::Socket> |
1072 | |
1087 | |
1073 | Provides various utility functions for (internet protocol) sockets, |
1088 | Provides various utility functions for (internet protocol) sockets, |
1074 | addresses and name resolution. Also functions to create non-blocking tcp |
1089 | addresses and name resolution. Also functions to create non-blocking tcp |
… | |
… | |
1076 | |
1091 | |
1077 | =item L<AnyEvent::Handle> |
1092 | =item L<AnyEvent::Handle> |
1078 | |
1093 | |
1079 | Provide read and write buffers, manages watchers for reads and writes, |
1094 | Provide read and write buffers, manages watchers for reads and writes, |
1080 | supports raw and formatted I/O, I/O queued and fully transparent and |
1095 | supports raw and formatted I/O, I/O queued and fully transparent and |
1081 | non-blocking SSL/TLS (via L<AnyEvent::TLS>. |
1096 | non-blocking SSL/TLS (via L<AnyEvent::TLS>). |
1082 | |
1097 | |
1083 | =item L<AnyEvent::DNS> |
1098 | =item L<AnyEvent::DNS> |
1084 | |
1099 | |
1085 | Provides rich asynchronous DNS resolver capabilities. |
1100 | Provides rich asynchronous DNS resolver capabilities. |
1086 | |
1101 | |
|
|
1102 | =item L<AnyEvent::HTTP>, L<AnyEvent::IRC>, L<AnyEvent::XMPP>, L<AnyEvent::GPSD>, L<AnyEvent::IGS>, L<AnyEvent::FCP> |
|
|
1103 | |
|
|
1104 | Implement event-based interfaces to the protocols of the same name (for |
|
|
1105 | the curious, IGS is the International Go Server and FCP is the Freenet |
|
|
1106 | Client Protocol). |
|
|
1107 | |
|
|
1108 | =item L<AnyEvent::Handle::UDP> |
|
|
1109 | |
|
|
1110 | Here be danger! |
|
|
1111 | |
|
|
1112 | As Pauli would put it, "Not only is it not right, it's not even wrong!" - |
|
|
1113 | there are so many things wrong with AnyEvent::Handle::UDP, most notably |
|
|
1114 | its use of a stream-based API with a protocol that isn't streamable, that |
|
|
1115 | the only way to improve it is to delete it. |
|
|
1116 | |
|
|
1117 | It features data corruption (but typically only under load) and general |
|
|
1118 | confusion. On top, the author is not only clueless about UDP but also |
|
|
1119 | fact-resistant - some gems of his understanding: "connect doesn't work |
|
|
1120 | with UDP", "UDP packets are not IP packets", "UDP only has datagrams, not |
|
|
1121 | packets", "I don't need to implement proper error checking as UDP doesn't |
|
|
1122 | support error checking" and so on - he doesn't even understand what's |
|
|
1123 | wrong with his module when it is explained to him. |
|
|
1124 | |
1087 | =item L<AnyEvent::HTTP> |
1125 | =item L<AnyEvent::DBI> |
1088 | |
1126 | |
1089 | A simple-to-use HTTP library that is capable of making a lot of concurrent |
1127 | Executes L<DBI> requests asynchronously in a proxy process for you, |
1090 | HTTP requests. |
1128 | notifying you in an event-based way when the operation is finished. |
|
|
1129 | |
|
|
1130 | =item L<AnyEvent::AIO> |
|
|
1131 | |
|
|
1132 | Truly asynchronous (as opposed to non-blocking) I/O, should be in the |
|
|
1133 | toolbox of every event programmer. AnyEvent::AIO transparently fuses |
|
|
1134 | L<IO::AIO> and AnyEvent together, giving AnyEvent access to event-based |
|
|
1135 | file I/O, and much more. |
1091 | |
1136 | |
1092 | =item L<AnyEvent::HTTPD> |
1137 | =item L<AnyEvent::HTTPD> |
1093 | |
1138 | |
1094 | Provides a simple web application server framework. |
1139 | A simple embedded webserver. |
1095 | |
1140 | |
1096 | =item L<AnyEvent::FastPing> |
1141 | =item L<AnyEvent::FastPing> |
1097 | |
1142 | |
1098 | The fastest ping in the west. |
1143 | The fastest ping in the west. |
1099 | |
|
|
1100 | =item L<AnyEvent::DBI> |
|
|
1101 | |
|
|
1102 | Executes L<DBI> requests asynchronously in a proxy process. |
|
|
1103 | |
|
|
1104 | =item L<AnyEvent::AIO> |
|
|
1105 | |
|
|
1106 | Truly asynchronous I/O, should be in the toolbox of every event |
|
|
1107 | programmer. AnyEvent::AIO transparently fuses L<IO::AIO> and AnyEvent |
|
|
1108 | together. |
|
|
1109 | |
|
|
1110 | =item L<AnyEvent::BDB> |
|
|
1111 | |
|
|
1112 | Truly asynchronous Berkeley DB access. AnyEvent::BDB transparently fuses |
|
|
1113 | L<BDB> and AnyEvent together. |
|
|
1114 | |
|
|
1115 | =item L<AnyEvent::GPSD> |
|
|
1116 | |
|
|
1117 | A non-blocking interface to gpsd, a daemon delivering GPS information. |
|
|
1118 | |
|
|
1119 | =item L<AnyEvent::IRC> |
|
|
1120 | |
|
|
1121 | AnyEvent based IRC client module family (replacing the older Net::IRC3). |
|
|
1122 | |
|
|
1123 | =item L<AnyEvent::XMPP> |
|
|
1124 | |
|
|
1125 | AnyEvent based XMPP (Jabber protocol) module family (replacing the older |
|
|
1126 | Net::XMPP2>. |
|
|
1127 | |
|
|
1128 | =item L<AnyEvent::IGS> |
|
|
1129 | |
|
|
1130 | A non-blocking interface to the Internet Go Server protocol (used by |
|
|
1131 | L<App::IGS>). |
|
|
1132 | |
|
|
1133 | =item L<Net::FCP> |
|
|
1134 | |
|
|
1135 | AnyEvent-based implementation of the Freenet Client Protocol, birthplace |
|
|
1136 | of AnyEvent. |
|
|
1137 | |
|
|
1138 | =item L<Event::ExecFlow> |
|
|
1139 | |
|
|
1140 | High level API for event-based execution flow control. |
|
|
1141 | |
1144 | |
1142 | =item L<Coro> |
1145 | =item L<Coro> |
1143 | |
1146 | |
1144 | Has special support for AnyEvent via L<Coro::AnyEvent>. |
1147 | Has special support for AnyEvent via L<Coro::AnyEvent>. |
1145 | |
1148 | |
… | |
… | |
1149 | |
1152 | |
1150 | package AnyEvent; |
1153 | package AnyEvent; |
1151 | |
1154 | |
1152 | # basically a tuned-down version of common::sense |
1155 | # basically a tuned-down version of common::sense |
1153 | sub common_sense { |
1156 | sub common_sense { |
1154 | # from common:.sense 1.0 |
1157 | # from common:.sense 3.4 |
1155 | ${^WARNING_BITS} = "\xfc\x3f\x33\x00\x0f\xf3\xcf\xc0\xf3\xfc\x33\x00"; |
1158 | ${^WARNING_BITS} ^= ${^WARNING_BITS} ^ "\x3c\x3f\x33\x00\x0f\xf0\x0f\xc0\xf0\xfc\x33\x00"; |
1156 | # use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl) |
1159 | # use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl) |
1157 | $^H |= 0x00000600; |
1160 | $^H |= 0x00000600; |
1158 | } |
1161 | } |
1159 | |
1162 | |
1160 | BEGIN { AnyEvent::common_sense } |
1163 | BEGIN { AnyEvent::common_sense } |
1161 | |
1164 | |
1162 | use Carp (); |
1165 | use Carp (); |
1163 | |
1166 | |
1164 | our $VERSION = '5.251'; |
1167 | our $VERSION = '5.34'; |
1165 | our $MODEL; |
1168 | our $MODEL; |
1166 | |
1169 | |
1167 | our $AUTOLOAD; |
1170 | our $AUTOLOAD; |
1168 | our @ISA; |
1171 | our @ISA; |
1169 | |
1172 | |
… | |
… | |
1207 | [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles |
1210 | [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles |
1208 | [Qt:: => AnyEvent::Impl::Qt::], # requires special main program |
1211 | [Qt:: => AnyEvent::Impl::Qt::], # requires special main program |
1209 | [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza |
1212 | [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza |
1210 | [Wx:: => AnyEvent::Impl::POE::], |
1213 | [Wx:: => AnyEvent::Impl::POE::], |
1211 | [Prima:: => AnyEvent::Impl::POE::], |
1214 | [Prima:: => AnyEvent::Impl::POE::], |
1212 | # IO::Async is just too broken - we would need workarounds for its |
|
|
1213 | # byzantine signal and broken child handling, among others. |
|
|
1214 | # IO::Async is rather hard to detect, as it doesn't have any |
|
|
1215 | # obvious default class. |
|
|
1216 | [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program |
|
|
1217 | [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program |
1215 | [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], |
1218 | [IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program |
1216 | [Cocoa::EventLoop:: => AnyEvent::Impl::Cocoa::], |
1219 | [AnyEvent::Impl::IOAsync:: => AnyEvent::Impl::IOAsync::], # requires special main program |
1217 | [FLTK:: => AnyEvent::Impl::FLTK::], |
1220 | ); |
1218 | ); |
1221 | |
1219 | |
1222 | our %method = map +($_ => 1), |
1220 | our %method = map +($_ => 1), |
1223 | qw(io timer time now now_update signal child idle condvar one_event DESTROY); |
1221 | qw(io timer time now now_update signal child idle condvar one_event DESTROY); |
1224 | |
1222 | |
… | |
… | |
1283 | last; |
1281 | last; |
1284 | } |
1282 | } |
1285 | } |
1283 | } |
1286 | |
1284 | |
1287 | $MODEL |
1285 | $MODEL |
1288 | or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.\n"; |
1286 | or die "AnyEvent: backend autodetection failed - did you properly install AnyEvent?\n"; |
1289 | } |
1287 | } |
1290 | } |
1288 | } |
1291 | |
1289 | |
1292 | @models = (); # free probe data |
1290 | @models = (); # free probe data |
1293 | |
1291 | |
1294 | push @{"$MODEL\::ISA"}, "AnyEvent::Base"; |
1292 | push @{"$MODEL\::ISA"}, "AnyEvent::Base"; |
1295 | unshift @ISA, $MODEL; |
1293 | unshift @ISA, $MODEL; |
1296 | |
1294 | |
1297 | # now nuke some methods that are overriden by the backend. |
1295 | # now nuke some methods that are overridden by the backend. |
1298 | # SUPER is not allowed. |
1296 | # SUPER is not allowed. |
1299 | for (qw(time signal child idle)) { |
1297 | for (qw(time signal child idle)) { |
1300 | undef &{"AnyEvent::Base::$_"} |
1298 | undef &{"AnyEvent::Base::$_"} |
1301 | if defined &{"$MODEL\::$_"}; |
1299 | if defined &{"$MODEL\::$_"}; |
1302 | } |
1300 | } |
1303 | |
1301 | |
1304 | require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT}; |
1302 | if ($ENV{PERL_ANYEVENT_STRICT}) { |
|
|
1303 | eval { require AnyEvent::Strict }; |
|
|
1304 | warn "AnyEvent: cannot load AnyEvent::Strict: $@" |
|
|
1305 | if $@ && $VERBOSE; |
|
|
1306 | } |
1305 | |
1307 | |
1306 | (shift @post_detect)->() while @post_detect; |
1308 | (shift @post_detect)->() while @post_detect; |
1307 | |
1309 | |
1308 | *post_detect = sub(&) { |
1310 | *post_detect = sub(&) { |
1309 | shift->(); |
1311 | shift->(); |
… | |
… | |
1616 | # default implementation for ->child |
1618 | # default implementation for ->child |
1617 | |
1619 | |
1618 | our %PID_CB; |
1620 | our %PID_CB; |
1619 | our $CHLD_W; |
1621 | our $CHLD_W; |
1620 | our $CHLD_DELAY_W; |
1622 | our $CHLD_DELAY_W; |
1621 | our $WNOHANG; |
|
|
1622 | |
1623 | |
1623 | # used by many Impl's |
1624 | # used by many Impl's |
1624 | sub _emit_childstatus($$) { |
1625 | sub _emit_childstatus($$) { |
1625 | my (undef, $rpid, $rstatus) = @_; |
1626 | my (undef, $rpid, $rstatus) = @_; |
1626 | |
1627 | |
… | |
… | |
1633 | eval q{ # poor man's autoloading {} |
1634 | eval q{ # poor man's autoloading {} |
1634 | *_sigchld = sub { |
1635 | *_sigchld = sub { |
1635 | my $pid; |
1636 | my $pid; |
1636 | |
1637 | |
1637 | AnyEvent->_emit_childstatus ($pid, $?) |
1638 | AnyEvent->_emit_childstatus ($pid, $?) |
1638 | while ($pid = waitpid -1, $WNOHANG) > 0; |
1639 | while ($pid = waitpid -1, WNOHANG) > 0; |
1639 | }; |
1640 | }; |
1640 | |
1641 | |
1641 | *child = sub { |
1642 | *child = sub { |
1642 | my (undef, %arg) = @_; |
1643 | my (undef, %arg) = @_; |
1643 | |
1644 | |
1644 | defined (my $pid = $arg{pid} + 0) |
1645 | defined (my $pid = $arg{pid} + 0) |
1645 | or Carp::croak "required option 'pid' is missing"; |
1646 | or Carp::croak "required option 'pid' is missing"; |
1646 | |
1647 | |
1647 | $PID_CB{$pid}{$arg{cb}} = $arg{cb}; |
1648 | $PID_CB{$pid}{$arg{cb}} = $arg{cb}; |
1648 | |
|
|
1649 | # WNOHANG is almost cetrainly 1 everywhere |
|
|
1650 | $WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/ |
|
|
1651 | ? 1 |
|
|
1652 | : eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1; |
|
|
1653 | |
1649 | |
1654 | unless ($CHLD_W) { |
1650 | unless ($CHLD_W) { |
1655 | $CHLD_W = AE::signal CHLD => \&_sigchld; |
1651 | $CHLD_W = AE::signal CHLD => \&_sigchld; |
1656 | # child could be a zombie already, so make at least one round |
1652 | # child could be a zombie already, so make at least one round |
1657 | &_sigchld; |
1653 | &_sigchld; |
… | |
… | |
1719 | |
1715 | |
1720 | package AnyEvent::CondVar; |
1716 | package AnyEvent::CondVar; |
1721 | |
1717 | |
1722 | our @ISA = AnyEvent::CondVar::Base::; |
1718 | our @ISA = AnyEvent::CondVar::Base::; |
1723 | |
1719 | |
|
|
1720 | # only to be used for subclassing |
|
|
1721 | sub new { |
|
|
1722 | my $class = shift; |
|
|
1723 | bless AnyEvent->condvar (@_), $class |
|
|
1724 | } |
|
|
1725 | |
1724 | package AnyEvent::CondVar::Base; |
1726 | package AnyEvent::CondVar::Base; |
1725 | |
1727 | |
1726 | #use overload |
1728 | #use overload |
1727 | # '&{}' => sub { my $self = shift; sub { $self->send (@_) } }, |
1729 | # '&{}' => sub { my $self = shift; sub { $self->send (@_) } }, |
1728 | # fallback => 1; |
1730 | # fallback => 1; |
… | |
… | |
1849 | check the arguments passed to most method calls. If it finds any problems, |
1851 | check the arguments passed to most method calls. If it finds any problems, |
1850 | it will croak. |
1852 | it will croak. |
1851 | |
1853 | |
1852 | In other words, enables "strict" mode. |
1854 | In other words, enables "strict" mode. |
1853 | |
1855 | |
1854 | Unlike C<use strict> (or it's modern cousin, C<< use L<common::sense> |
1856 | Unlike C<use strict> (or its modern cousin, C<< use L<common::sense> |
1855 | >>, it is definitely recommended to keep it off in production. Keeping |
1857 | >>, it is definitely recommended to keep it off in production. Keeping |
1856 | C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs |
1858 | C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs |
1857 | can be very useful, however. |
1859 | can be very useful, however. |
1858 | |
1860 | |
1859 | =item C<PERL_ANYEVENT_MODEL> |
1861 | =item C<PERL_ANYEVENT_MODEL> |
… | |
… | |
2505 | unless defined $SIG{PIPE}; |
2507 | unless defined $SIG{PIPE}; |
2506 | |
2508 | |
2507 | =head1 RECOMMENDED/OPTIONAL MODULES |
2509 | =head1 RECOMMENDED/OPTIONAL MODULES |
2508 | |
2510 | |
2509 | One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and |
2511 | One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and |
2510 | it's built-in modules) are required to use it. |
2512 | its built-in modules) are required to use it. |
2511 | |
2513 | |
2512 | That does not mean that AnyEvent won't take advantage of some additional |
2514 | That does not mean that AnyEvent won't take advantage of some additional |
2513 | modules if they are installed. |
2515 | modules if they are installed. |
2514 | |
2516 | |
2515 | This section explains which additional modules will be used, and how they |
2517 | This section explains which additional modules will be used, and how they |
… | |
… | |
2573 | the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL. |
2575 | the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL. |
2574 | |
2576 | |
2575 | =item L<Time::HiRes> |
2577 | =item L<Time::HiRes> |
2576 | |
2578 | |
2577 | This module is part of perl since release 5.008. It will be used when the |
2579 | This module is part of perl since release 5.008. It will be used when the |
2578 | chosen event library does not come with a timing source on it's own. The |
2580 | chosen event library does not come with a timing source of its own. The |
2579 | pure-perl event loop (L<AnyEvent::Impl::Perl>) will additionally use it to |
2581 | pure-perl event loop (L<AnyEvent::Impl::Perl>) will additionally use it to |
2580 | try to use a monotonic clock for timing stability. |
2582 | try to use a monotonic clock for timing stability. |
2581 | |
2583 | |
2582 | =back |
2584 | =back |
2583 | |
2585 | |
… | |
… | |
2646 | pronounced). |
2648 | pronounced). |
2647 | |
2649 | |
2648 | |
2650 | |
2649 | =head1 SEE ALSO |
2651 | =head1 SEE ALSO |
2650 | |
2652 | |
|
|
2653 | Tutorial/Introduction: L<AnyEvent::Intro>. |
|
|
2654 | |
|
|
2655 | FAQ: L<AnyEvent::FAQ>. |
|
|
2656 | |
2651 | Utility functions: L<AnyEvent::Util>. |
2657 | Utility functions: L<AnyEvent::Util>. |
2652 | |
2658 | |
2653 | Event modules: L<EV>, L<EV::Glib>, L<Glib::EV>, L<Event>, L<Glib::Event>, |
2659 | Event modules: L<EV>, L<EV::Glib>, L<Glib::EV>, L<Event>, L<Glib::Event>, |
2654 | L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. |
2660 | L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. |
2655 | |
2661 | |
… | |
… | |
2661 | Non-blocking file handles, sockets, TCP clients and |
2667 | Non-blocking file handles, sockets, TCP clients and |
2662 | servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>. |
2668 | servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>. |
2663 | |
2669 | |
2664 | Asynchronous DNS: L<AnyEvent::DNS>. |
2670 | Asynchronous DNS: L<AnyEvent::DNS>. |
2665 | |
2671 | |
2666 | Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, |
2672 | Thread support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>. |
2667 | L<Coro::Event>, |
|
|
2668 | |
2673 | |
2669 | Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::XMPP>, |
2674 | Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::IRC>, |
2670 | L<AnyEvent::HTTP>. |
2675 | L<AnyEvent::HTTP>. |
2671 | |
2676 | |
2672 | |
2677 | |
2673 | =head1 AUTHOR |
2678 | =head1 AUTHOR |
2674 | |
2679 | |