… | |
… | |
7 | |
7 | |
8 | =head1 SYNOPSIS |
8 | =head1 SYNOPSIS |
9 | |
9 | |
10 | use AnyEvent; |
10 | use AnyEvent; |
11 | |
11 | |
|
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12 | # if you prefer function calls, look at the AE manpage for |
|
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13 | # an alternative API. |
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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 |
… | |
… | |
43 | 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 |
44 | L<AnyEvent::Intro> manpage. |
47 | L<AnyEvent::Intro> manpage. |
45 | |
48 | |
46 | =head1 SUPPORT |
49 | =head1 SUPPORT |
47 | |
50 | |
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51 | An FAQ document is available as L<AnyEvent::FAQ>. |
|
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52 | |
48 | 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 |
49 | channel, too. |
54 | channel, too. |
50 | |
55 | |
51 | 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 |
52 | Repository>, at L<http://anyevent.schmorp.de>, for more info. |
57 | Repository>, at L<http://anyevent.schmorp.de>, for more info. |
53 | |
58 | |
… | |
… | |
73 | 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 |
74 | model you use. |
79 | model you use. |
75 | |
80 | |
76 | 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 |
77 | 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 |
78 | 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 |
79 | cannot use anything else, as they are simply incompatible to everything |
84 | cannot use anything else, as they are simply incompatible to everything |
80 | 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 |
81 | 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. |
82 | |
87 | |
83 | AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works |
88 | AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works |
84 | 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 |
85 | 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 |
86 | 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 |
87 | 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 |
88 | 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 |
89 | 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, |
90 | to AnyEvent, too, so it is future-proof). |
95 | so it is future-proof). |
91 | |
96 | |
92 | 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 |
93 | 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 |
94 | 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 |
95 | 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 |
96 | 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 |
97 | technically possible. |
102 | technically possible. |
98 | |
103 | |
99 | Of course, AnyEvent comes with a big (and fully optional!) toolbox |
104 | Of course, AnyEvent comes with a big (and fully optional!) toolbox |
100 | of useful functionality, such as an asynchronous DNS resolver, 100% |
105 | of useful functionality, such as an asynchronous DNS resolver, 100% |
… | |
… | |
106 | 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 |
107 | model, you should I<not> use this module. |
112 | model, you should I<not> use this module. |
108 | |
113 | |
109 | =head1 DESCRIPTION |
114 | =head1 DESCRIPTION |
110 | |
115 | |
111 | L<AnyEvent> provides an identical interface to multiple event loops. This |
116 | L<AnyEvent> provides a uniform interface to various event loops. This |
112 | allows module authors to utilise an event loop without forcing module |
117 | allows module authors to use event loop functionality without forcing |
113 | 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 |
114 | peacefully at any one time). |
119 | than one event loop cannot coexist peacefully). |
115 | |
120 | |
116 | 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> |
117 | module. |
122 | module. |
118 | |
123 | |
119 | 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 |
120 | 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 |
121 | following modules is already loaded: L<EV>, |
126 | following modules is already loaded: L<EV>, L<AnyEvent::Loop>, |
122 | 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 |
123 | 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 |
124 | 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 |
125 | adaptor should always succeed) in the order given. The first one that can |
130 | available, the pure-perl L<AnyEvent::Loop> should always work, so |
126 | be successfully loaded will be used. If, after this, still none could be |
131 | the other two are not normally tried. |
127 | found, AnyEvent will fall back to a pure-perl event loop, which is not |
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128 | very efficient, but should work everywhere. |
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129 | |
132 | |
130 | Because AnyEvent first checks for modules that are already loaded, loading |
133 | Because AnyEvent first checks for modules that are already loaded, loading |
131 | an event model explicitly before first using AnyEvent will likely make |
134 | an event model explicitly before first using AnyEvent will likely make |
132 | that model the default. For example: |
135 | that 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 | |
139 | 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 |
140 | 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, |
141 | use AnyEvent so their modules work together with others seamlessly... |
144 | as very few modules hardcode event loops without announcing this very |
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145 | loudly. |
142 | |
146 | |
143 | The pure-perl implementation of AnyEvent is called |
147 | The pure-perl implementation of AnyEvent is called C<AnyEvent::Loop>. Like |
144 | C<AnyEvent::Impl::Perl>. Like other event modules you can load it |
148 | other event modules you can load it explicitly and enjoy the high |
145 | explicitly and enjoy the high availability of that event loop :) |
149 | availability of that event loop :) |
146 | |
150 | |
147 | =head1 WATCHERS |
151 | =head1 WATCHERS |
148 | |
152 | |
149 | AnyEvent has the central concept of a I<watcher>, which is an object that |
153 | AnyEvent has the central concept of a I<watcher>, which is an object that |
150 | stores relevant data for each kind of event you are waiting for, such as |
154 | stores relevant data for each kind of event you are waiting for, such as |
… | |
… | |
155 | 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 |
156 | is in control). |
160 | is in control). |
157 | |
161 | |
158 | Note that B<callbacks must not permanently change global variables> |
162 | Note that B<callbacks must not permanently change global variables> |
159 | 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<< |
160 | 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 |
161 | 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 |
162 | widely between event loops. |
166 | widely between event loops. |
163 | |
167 | |
164 | 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 |
165 | 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 |
166 | to it). |
170 | to it). |
167 | |
171 | |
168 | 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. |
169 | |
173 | |
170 | Many watchers either are used with "recursion" (repeating timers for |
174 | Many watchers either are used with "recursion" (repeating timers for |
171 | 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. |
172 | |
176 | |
173 | An any way to achieve that is this pattern: |
177 | One 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 | |
211 | 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. |
212 | 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 |
213 | underlying file descriptor. |
217 | underlying file descriptor. |
214 | |
218 | |
215 | Some event loops issue spurious readyness notifications, so you should |
219 | Some event loops issue spurious readiness notifications, so you should |
216 | 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 |
217 | handles. |
221 | handles. |
218 | |
222 | |
219 | 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 |
220 | watcher. |
224 | watcher. |
… | |
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244 | |
248 | |
245 | Although the callback might get passed parameters, their value and |
249 | Although the callback might get passed parameters, their value and |
246 | presence is undefined and you cannot rely on them. Portable AnyEvent |
250 | presence is undefined and you cannot rely on them. Portable AnyEvent |
247 | callbacks cannot use arguments passed to time watcher callbacks. |
251 | callbacks cannot use arguments passed to time watcher callbacks. |
248 | |
252 | |
249 | 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 |
250 | parameter, C<interval>, as a strictly positive number (> 0), then the |
254 | parameter, C<interval>, as a strictly positive number (> 0), then the |
251 | callback will be invoked regularly at that interval (in fractional |
255 | callback will be invoked regularly at that interval (in fractional |
252 | 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 |
253 | 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. |
254 | |
258 | |
255 | The callback will be rescheduled before invoking the callback, but no |
259 | The callback will be rescheduled before invoking the callback, but no |
256 | 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 |
257 | only approximate. |
261 | only approximate. |
258 | |
262 | |
259 | Example: fire an event after 7.7 seconds. |
263 | Example: 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 { |
… | |
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279 | |
283 | |
280 | 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 |
281 | use absolute time internally. This makes a difference when your clock |
285 | use 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 |
283 | 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 |
284 | 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. |
285 | |
289 | |
286 | 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 |
287 | 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 |
288 | 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) |
289 | timers. |
293 | timers. |
290 | |
294 | |
291 | AnyEvent always prefers relative timers, if available, matching the |
295 | AnyEvent always prefers relative timers, if available, matching the |
292 | AnyEvent API. |
296 | AnyEvent API. |
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314 | 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 |
315 | function to call when you want to know the current time.> |
319 | function to call when you want to know the current time.> |
316 | |
320 | |
317 | This function is also often faster then C<< AnyEvent->time >>, and |
321 | This function is also often faster then C<< AnyEvent->time >>, and |
318 | thus the preferred method if you want some timestamp (for example, |
322 | thus the preferred method if you want some timestamp (for example, |
319 | L<AnyEvent::Handle> uses this to update it's activity timeouts). |
323 | L<AnyEvent::Handle> uses this to update its activity timeouts). |
320 | |
324 | |
321 | 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 |
322 | with your timing, you can skip it without bad conscience. |
326 | with your timing; you can skip it without a bad conscience. |
323 | |
327 | |
324 | 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> |
325 | and L<EV> and the following set-up: |
329 | and L<EV> and the following set-up: |
326 | |
330 | |
327 | 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 |
328 | time=500 (assume no other callbacks delay processing). In your callback, |
332 | time=500 (assume no other callbacks delay processing). In your callback, |
329 | 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 |
330 | 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 |
331 | after three seconds. |
335 | after three seconds. |
332 | |
336 | |
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352 | difference between C<< AnyEvent->time >> and C<< AnyEvent->now >> into |
356 | difference between C<< AnyEvent->time >> and C<< AnyEvent->now >> into |
353 | account. |
357 | account. |
354 | |
358 | |
355 | =item AnyEvent->now_update |
359 | =item AnyEvent->now_update |
356 | |
360 | |
357 | Some event loops (such as L<EV> or L<AnyEvent::Impl::Perl>) cache |
361 | Some event loops (such as L<EV> or L<AnyEvent::Loop>) cache the current |
358 | the current time for each loop iteration (see the discussion of L<< |
362 | time for each loop iteration (see the discussion of L<< AnyEvent->now >>, |
359 | AnyEvent->now >>, above). |
363 | above). |
360 | |
364 | |
361 | When a callback runs for a long time (or when the process sleeps), then |
365 | When a callback runs for a long time (or when the process sleeps), then |
362 | this "current" time will differ substantially from the real time, which |
366 | this "current" time will differ substantially from the real time, which |
363 | might affect timers and time-outs. |
367 | might affect timers and time-outs. |
364 | |
368 | |
365 | When this is the case, you can call this method, which will update the |
369 | When this is the case, you can call this method, which will update the |
366 | event loop's idea of "current time". |
370 | event loop's idea of "current time". |
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371 | |
|
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372 | A typical example would be a script in a web server (e.g. C<mod_perl>) - |
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373 | when mod_perl executes the script, then the event loop will have the wrong |
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374 | idea about the "current time" (being potentially far in the past, when the |
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375 | script ran the last time). In that case you should arrange a call to C<< |
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376 | AnyEvent->now_update >> each time the web server process wakes up again |
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377 | (e.g. at the start of your script, or in a handler). |
367 | |
378 | |
368 | Note that updating the time I<might> cause some events to be handled. |
379 | Note that updating the time I<might> cause some events to be handled. |
369 | |
380 | |
370 | =back |
381 | =back |
371 | |
382 | |
… | |
… | |
396 | |
407 | |
397 | Example: exit on SIGINT |
408 | Example: 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 | |
|
|
414 | While restart behaviour is up to the event loop implementation, most will |
|
|
415 | not restart syscalls (that includes L<Async::Interrupt> and AnyEvent's |
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416 | pure perl implementation). |
|
|
417 | |
|
|
418 | =head3 Safe/Unsafe Signals |
|
|
419 | |
|
|
420 | Perl signals can be either "safe" (synchronous to opcode handling) or |
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|
421 | "unsafe" (asynchronous) - the former might get delayed indefinitely, the |
|
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422 | latter might corrupt your memory. |
|
|
423 | |
|
|
424 | AnyEvent signal handlers are, in addition, synchronous to the event loop, |
|
|
425 | i.e. they will not interrupt your running perl program but will only be |
|
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426 | called as part of the normal event handling (just like timer, I/O etc. |
|
|
427 | callbacks, too). |
|
|
428 | |
401 | =head3 Signal Races, Delays and Workarounds |
429 | =head3 Signal Races, Delays and Workarounds |
402 | |
430 | |
403 | 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 |
404 | 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 |
405 | do race-free signal handling in perl, requiring C libraries for |
433 | do race-free signal handling in perl, requiring C libraries for |
406 | 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, |
407 | 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 |
408 | specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This |
436 | specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This |
409 | 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, |
410 | and should be left alone otherwise. This variable determines how often |
438 | and should be left alone otherwise. This variable determines how often |
411 | 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 |
… | |
… | |
413 | saving. |
441 | saving. |
414 | |
442 | |
415 | All these problems can be avoided by installing the optional |
443 | All these problems can be avoided by installing the optional |
416 | 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 |
417 | 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> |
418 | (and not with L<POE> currently, as POE does it's own workaround with |
446 | (and not with L<POE> currently, as POE does its own workaround with |
419 | 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. |
420 | |
448 | |
421 | =head2 CHILD PROCESS WATCHERS |
449 | =head2 CHILD PROCESS WATCHERS |
422 | |
450 | |
423 | $w = AnyEvent->child (pid => <process id>, cb => <callback>); |
451 | $w = AnyEvent->child (pid => <process id>, cb => <callback>); |
424 | |
452 | |
425 | 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. |
426 | |
454 | |
427 | 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, |
428 | 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 |
429 | 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 |
430 | 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 |
431 | (stopped/continued). |
459 | (stopped/continued). |
432 | |
460 | |
… | |
… | |
454 | thing in an AnyEvent program, you I<have> to create at least one |
482 | thing in an AnyEvent program, you I<have> to create at least one |
455 | watcher before you C<fork> the child (alternatively, you can call |
483 | watcher before you C<fork> the child (alternatively, you can call |
456 | C<AnyEvent::detect>). |
484 | C<AnyEvent::detect>). |
457 | |
485 | |
458 | As most event loops do not support waiting for child events, they will be |
486 | As most event loops do not support waiting for child events, they will be |
459 | emulated by AnyEvent in most cases, in which the latency and race problems |
487 | emulated by AnyEvent in most cases, in which case the latency and race |
460 | mentioned in the description of signal watchers apply. |
488 | problems mentioned in the description of signal watchers apply. |
461 | |
489 | |
462 | Example: fork a process and wait for it |
490 | Example: fork a process and wait for it |
463 | |
491 | |
464 | my $done = AnyEvent->condvar; |
492 | my $done = AnyEvent->condvar; |
465 | |
493 | |
… | |
… | |
479 | |
507 | |
480 | =head2 IDLE WATCHERS |
508 | =head2 IDLE WATCHERS |
481 | |
509 | |
482 | $w = AnyEvent->idle (cb => <callback>); |
510 | $w = AnyEvent->idle (cb => <callback>); |
483 | |
511 | |
484 | Sometimes there is a need to do something, but it is not so important |
512 | This will repeatedly invoke the callback after the process becomes idle, |
485 | to do it instantly, but only when there is nothing better to do. This |
513 | until 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 |
|
|
487 | attention by the event loop". |
|
|
488 | |
514 | |
489 | Idle watchers ideally get invoked when the event loop has nothing |
515 | Idle watchers are useful when there is a need to do something, but it |
490 | better to do, just before it would block the process to wait for new |
516 | is not so important (or wise) to do it instantly. The callback will be |
491 | events. Instead of blocking, the idle watcher is invoked. |
517 | invoked only when there is "nothing better to do", which is usually |
|
|
518 | defined as "all outstanding events have been handled and no new events |
|
|
519 | have been detected". That means that idle watchers ideally get invoked |
|
|
520 | when the event loop has just polled for new events but none have been |
|
|
521 | detected. Instead of blocking to wait for more events, the idle watchers |
|
|
522 | will be invoked. |
492 | |
523 | |
493 | Most event loops unfortunately do not really support idle watchers (only |
524 | Unfortunately, most event loops do not really support idle watchers (only |
494 | EV, Event and Glib do it in a usable fashion) - for the rest, AnyEvent |
525 | EV, Event and Glib do it in a usable fashion) - for the rest, AnyEvent |
495 | will simply call the callback "from time to time". |
526 | will simply call the callback "from time to time". |
496 | |
527 | |
497 | Example: read lines from STDIN, but only process them when the |
528 | Example: read lines from STDIN, but only process them when the |
498 | program is otherwise idle: |
529 | program is otherwise idle: |
… | |
… | |
526 | will actively watch for new events and call your callbacks. |
557 | will actively watch for new events and call your callbacks. |
527 | |
558 | |
528 | 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 |
529 | 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). |
530 | |
561 | |
531 | 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 |
532 | because they represent a condition that must become true. |
563 | they represent a condition that must become true. |
533 | |
564 | |
534 | 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. |
535 | |
566 | |
536 | Condition variables can be created by calling the C<< AnyEvent->condvar |
567 | Condition variables can be created by calling the C<< AnyEvent->condvar |
537 | >> method, usually without arguments. The only argument pair allowed is |
568 | >> method, usually without arguments. The only argument pair allowed is |
… | |
… | |
542 | After creation, the condition variable is "false" until it becomes "true" |
573 | After creation, the condition variable is "false" until it becomes "true" |
543 | 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 |
544 | 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<< |
545 | ->send >> method). |
576 | ->send >> method). |
546 | |
577 | |
547 | 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 |
548 | 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: |
549 | in time where multiple outstanding events have been processed. And yet |
580 | |
550 | another way to call them is transactions - each condition variable can be |
581 | =over 4 |
551 | used to represent a transaction, which finishes at some point and delivers |
582 | |
552 | 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 |
553 | 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 |
554 | |
601 | |
555 | Condition variables are very useful to signal that something has finished, |
602 | Condition variables are very useful to signal that something has finished, |
556 | 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, |
557 | 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 |
558 | 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 |
… | |
… | |
571 | |
618 | |
572 | 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 |
573 | 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 |
574 | 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 |
575 | 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 |
576 | it's C<new> method in your own C<new> method. |
623 | its C<new> method in your own C<new> method. |
577 | |
624 | |
578 | 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 |
579 | eventually calls C<< -> send >>, and the "consumer side", which waits |
626 | eventually calls C<< -> send >>, and the "consumer side", which waits |
580 | for the send to occur. |
627 | for the send to occur. |
581 | |
628 | |
582 | Example: wait for a timer. |
629 | Example: wait for a timer. |
583 | |
630 | |
584 | # wait till the result is ready |
631 | # condition: "wait till the timer is fired" |
585 | my $result_ready = AnyEvent->condvar; |
632 | my $timer_fired = AnyEvent->condvar; |
586 | |
633 | |
587 | # do something such as adding a timer |
634 | # create the timer - we could wait for, say |
588 | # or socket watcher the calls $result_ready->send |
635 | # a handle becomign ready, or even an |
589 | # when the "result" is ready. |
636 | # AnyEvent::HTTP request to finish, but |
590 | # in this case, we simply use a timer: |
637 | # in this case, we simply use a timer: |
591 | my $w = AnyEvent->timer ( |
638 | my $w = AnyEvent->timer ( |
592 | after => 1, |
639 | after => 1, |
593 | cb => sub { $result_ready->send }, |
640 | cb => sub { $timer_fired->send }, |
594 | ); |
641 | ); |
595 | |
642 | |
596 | # this "blocks" (while handling events) till the callback |
643 | # this "blocks" (while handling events) till the callback |
597 | # calls -<send |
644 | # calls ->send |
598 | $result_ready->recv; |
645 | $timer_fired->recv; |
599 | |
646 | |
600 | 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 |
601 | variables are also callable directly. |
648 | variables are also callable directly. |
602 | |
649 | |
603 | my $done = AnyEvent->condvar; |
650 | my $done = AnyEvent->condvar; |
… | |
… | |
646 | 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 |
647 | C<send>. |
694 | C<send>. |
648 | |
695 | |
649 | =item $cv->croak ($error) |
696 | =item $cv->croak ($error) |
650 | |
697 | |
651 | 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 |
652 | C<Carp::croak> with the given error message/object/scalar. |
699 | C<Carp::croak> with the given error message/object/scalar. |
653 | |
700 | |
654 | 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 |
655 | 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 |
656 | delays the error detetcion, but has the overwhelmign advantage that it |
703 | delays the error detection, but has the overwhelming advantage that it |
657 | 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 |
658 | 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 |
659 | the problem. |
706 | the problem. |
660 | |
707 | |
661 | =item $cv->begin ([group callback]) |
708 | =item $cv->begin ([group callback]) |
662 | |
709 | |
663 | =item $cv->end |
710 | =item $cv->end |
… | |
… | |
666 | one. For example, a function that pings many hosts in parallel might want |
713 | one. For example, a function that pings many hosts in parallel might want |
667 | to use a condition variable for the whole process. |
714 | to use a condition variable for the whole process. |
668 | |
715 | |
669 | Every call to C<< ->begin >> will increment a counter, and every call to |
716 | Every call to C<< ->begin >> will increment a counter, and every call to |
670 | C<< ->end >> will decrement it. If the counter reaches C<0> in C<< ->end |
717 | C<< ->end >> will decrement it. If the counter reaches C<0> in C<< ->end |
671 | >>, the (last) callback passed to C<begin> will be executed. That callback |
718 | >>, the (last) callback passed to C<begin> will be executed, passing the |
672 | is I<supposed> to call C<< ->send >>, but that is not required. If no |
719 | condvar as first argument. That callback is I<supposed> to call C<< ->send |
673 | callback was set, C<send> will be called without any arguments. |
720 | >>, but that is not required. If no group callback was set, C<send> will |
|
|
721 | be called without any arguments. |
674 | |
722 | |
675 | You can think of C<< $cv->send >> giving you an OR condition (one call |
723 | You can think of C<< $cv->send >> giving you an OR condition (one call |
676 | sends), while C<< $cv->begin >> and C<< $cv->end >> giving you an AND |
724 | sends), while C<< $cv->begin >> and C<< $cv->end >> giving you an AND |
677 | condition (all C<begin> calls must be C<end>'ed before the condvar sends). |
725 | condition (all C<begin> calls must be C<end>'ed before the condvar sends). |
678 | |
726 | |
… | |
… | |
700 | 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 |
701 | sending. |
749 | sending. |
702 | |
750 | |
703 | The ping example mentioned above is slightly more complicated, as the |
751 | The ping example mentioned above is slightly more complicated, as the |
704 | 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 |
705 | begung can potentially be zero: |
753 | begun can potentially be zero: |
706 | |
754 | |
707 | my $cv = AnyEvent->condvar; |
755 | my $cv = AnyEvent->condvar; |
708 | |
756 | |
709 | my %result; |
757 | my %result; |
710 | $cv->begin (sub { $cv->send (\%result) }); |
758 | $cv->begin (sub { shift->send (\%result) }); |
711 | |
759 | |
712 | for my $host (@list_of_hosts) { |
760 | for my $host (@list_of_hosts) { |
713 | $cv->begin; |
761 | $cv->begin; |
714 | ping_host_then_call_callback $host, sub { |
762 | ping_host_then_call_callback $host, sub { |
715 | $result{$host} = ...; |
763 | $result{$host} = ...; |
… | |
… | |
731 | 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 |
732 | 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 |
733 | doesn't execute once). |
781 | doesn't execute once). |
734 | |
782 | |
735 | 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 |
736 | 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 |
737 | 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 |
738 | 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, |
739 | call C<end>. |
787 | call C<end>. |
740 | |
788 | |
741 | =back |
789 | =back |
… | |
… | |
748 | =over 4 |
796 | =over 4 |
749 | |
797 | |
750 | =item $cv->recv |
798 | =item $cv->recv |
751 | |
799 | |
752 | Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak |
800 | Wait (blocking if necessary) until the C<< ->send >> or C<< ->croak |
753 | >> methods have been called on c<$cv>, while servicing other watchers |
801 | >> methods have been called on C<$cv>, while servicing other watchers |
754 | normally. |
802 | normally. |
755 | |
803 | |
756 | 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 |
757 | will return immediately. |
805 | will return immediately. |
758 | |
806 | |
… | |
… | |
775 | 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 |
776 | condition variables with some kind of request results and supporting |
824 | condition variables with some kind of request results and supporting |
777 | 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, |
778 | while still supporting blocking waits if the caller so desires). |
826 | while still supporting blocking waits if the caller so desires). |
779 | |
827 | |
780 | 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 |
781 | 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 |
782 | 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 |
783 | waits otherwise. |
831 | waits otherwise. |
784 | |
832 | |
785 | =item $bool = $cv->ready |
833 | =item $bool = $cv->ready |
… | |
… | |
790 | =item $cb = $cv->cb ($cb->($cv)) |
838 | =item $cb = $cv->cb ($cb->($cv)) |
791 | |
839 | |
792 | 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 |
793 | replaces it before doing so. |
841 | replaces it before doing so. |
794 | |
842 | |
795 | 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 |
796 | "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 |
797 | 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 |
798 | 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. |
799 | |
848 | |
800 | =back |
849 | =back |
801 | |
850 | |
802 | =head1 SUPPORTED EVENT LOOPS/BACKENDS |
851 | =head1 SUPPORTED EVENT LOOPS/BACKENDS |
803 | |
852 | |
… | |
… | |
811 | use. If EV is not installed, then AnyEvent will fall back to its own |
860 | use. If EV is not installed, then AnyEvent will fall back to its own |
812 | pure-perl implementation, which is available everywhere as it comes with |
861 | pure-perl implementation, which is available everywhere as it comes with |
813 | AnyEvent itself. |
862 | AnyEvent itself. |
814 | |
863 | |
815 | AnyEvent::Impl::EV based on EV (interface to libev, best choice). |
864 | AnyEvent::Impl::EV based on EV (interface to libev, best choice). |
816 | AnyEvent::Impl::Perl pure-perl implementation, fast and portable. |
865 | AnyEvent::Impl::Perl pure-perl AnyEvent::Loop, fast and portable. |
817 | |
866 | |
818 | =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. |
819 | |
868 | |
820 | 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 |
821 | 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 |
822 | them. This means that AnyEvent will automatically pick the right backend |
871 | them. This means that AnyEvent will automatically pick the right backend |
823 | 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 |
824 | 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. |
825 | |
874 | |
… | |
… | |
827 | AnyEvent::Impl::Glib based on Glib, slow but very stable. |
876 | AnyEvent::Impl::Glib based on Glib, slow but very stable. |
828 | AnyEvent::Impl::Tk based on Tk, very broken. |
877 | AnyEvent::Impl::Tk based on Tk, very broken. |
829 | AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. |
878 | AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. |
830 | AnyEvent::Impl::POE based on POE, very slow, some limitations. |
879 | AnyEvent::Impl::POE based on POE, very slow, some limitations. |
831 | 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. |
832 | |
884 | |
833 | =item Backends with special needs. |
885 | =item Backends with special needs. |
834 | |
886 | |
835 | Qt requires the Qt::Application to be instantiated first, but will |
887 | Qt requires the Qt::Application to be instantiated first, but will |
836 | otherwise be picked up automatically. As long as the main program |
888 | otherwise be picked up automatically. As long as the main program |
837 | instantiates the application before any AnyEvent watchers are created, |
889 | instantiates the application before any AnyEvent watchers are created, |
838 | everything should just work. |
890 | everything should just work. |
839 | |
891 | |
840 | AnyEvent::Impl::Qt based on Qt. |
892 | AnyEvent::Impl::Qt based on Qt. |
841 | |
893 | |
842 | Support for IO::Async can only be partial, as it is too broken and |
|
|
843 | architecturally limited to even support the AnyEvent API. It also |
|
|
844 | is the only event loop that needs the loop to be set explicitly, so |
|
|
845 | it can only be used by a main program knowing about AnyEvent. See |
|
|
846 | L<AnyEvent::Impl::Async> for the gory details. |
|
|
847 | |
|
|
848 | AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed. |
|
|
849 | |
|
|
850 | =item Event loops that are indirectly supported via other backends. |
894 | =item Event loops that are indirectly supported via other backends. |
851 | |
895 | |
852 | Some event loops can be supported via other modules: |
896 | Some event loops can be supported via other modules: |
853 | |
897 | |
854 | 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>. |
… | |
… | |
879 | 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 |
880 | backend has been autodetected. |
924 | backend has been autodetected. |
881 | |
925 | |
882 | 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 |
883 | 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 |
884 | 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 |
885 | 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 |
886 | will be C<urxvt::anyevent>). |
930 | will be C<urxvt::anyevent>). |
887 | |
931 | |
888 | =item AnyEvent::detect |
932 | =item AnyEvent::detect |
889 | |
933 | |
890 | Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model |
934 | Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model |
891 | 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 |
892 | 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 |
893 | runtime, and not e.g. while initialising of your module. |
937 | runtime, and not e.g. during initialisation of your module. |
894 | |
938 | |
895 | If you need to do some initialisation before AnyEvent watchers are |
939 | If you need to do some initialisation before AnyEvent watchers are |
896 | created, use C<post_detect>. |
940 | created, use C<post_detect>. |
897 | |
941 | |
898 | =item $guard = AnyEvent::post_detect { BLOCK } |
942 | =item $guard = AnyEvent::post_detect { BLOCK } |
899 | |
943 | |
900 | Arranges for the code block to be executed as soon as the event model is |
944 | Arranges for the code block to be executed as soon as the event model is |
901 | autodetected (or immediately if this has already happened). |
945 | autodetected (or immediately if that has already happened). |
902 | |
946 | |
903 | The block will be executed I<after> the actual backend has been detected |
947 | The block will be executed I<after> the actual backend has been detected |
904 | (C<$AnyEvent::MODEL> is set), but I<before> any watchers have been |
948 | (C<$AnyEvent::MODEL> is set), but I<before> any watchers have been |
905 | created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do |
949 | created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do |
906 | other initialisations - see the sources of L<AnyEvent::Strict> or |
950 | other initialisations - see the sources of L<AnyEvent::Strict> or |
… | |
… | |
915 | that automatically removes the callback again when it is destroyed (or |
959 | that automatically removes the callback again when it is destroyed (or |
916 | C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for |
960 | C<undef> when the hook was immediately executed). See L<AnyEvent::AIO> for |
917 | a case where this is useful. |
961 | a case where this is useful. |
918 | |
962 | |
919 | Example: Create a watcher for the IO::AIO module and store it in |
963 | Example: Create a watcher for the IO::AIO module and store it in |
920 | C<$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. |
921 | |
965 | |
922 | our WATCHER; |
966 | our WATCHER; |
923 | |
967 | |
924 | my $guard = AnyEvent::post_detect { |
968 | my $guard = AnyEvent::post_detect { |
925 | $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); |
… | |
… | |
933 | $WATCHER ||= $guard; |
977 | $WATCHER ||= $guard; |
934 | |
978 | |
935 | =item @AnyEvent::post_detect |
979 | =item @AnyEvent::post_detect |
936 | |
980 | |
937 | If there are any code references in this array (you can C<push> to it |
981 | If there are any code references in this array (you can C<push> to it |
938 | before or after loading AnyEvent), then they will called directly after |
982 | before or after loading AnyEvent), then they will be called directly |
939 | the event loop has been chosen. |
983 | after the event loop has been chosen. |
940 | |
984 | |
941 | You should check C<$AnyEvent::MODEL> before adding to this array, though: |
985 | You should check C<$AnyEvent::MODEL> before adding to this array, though: |
942 | 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 |
943 | array will be ignored. |
987 | array will be ignored. |
944 | |
988 | |
945 | Best use C<AnyEvent::post_detect { BLOCK }> when your application allows |
989 | Best use C<AnyEvent::post_detect { BLOCK }> when your application allows |
946 | it,as it takes care of these details. |
990 | it, as it takes care of these details. |
947 | |
991 | |
948 | This variable is mainly useful for modules that can do something useful |
992 | This variable is mainly useful for modules that can do something useful |
949 | when AnyEvent is used and thus want to know when it is initialised, but do |
993 | when AnyEvent is used and thus want to know when it is initialised, but do |
950 | not need to even load it by default. This array provides the means to hook |
994 | not need to even load it by default. This array provides the means to hook |
951 | into AnyEvent passively, without loading it. |
995 | into AnyEvent passively, without loading it. |
952 | |
996 | |
|
|
997 | Example: To load Coro::AnyEvent whenever Coro and AnyEvent are used |
|
|
998 | together, you could put this into Coro (this is the actual code used by |
|
|
999 | Coro to accomplish this): |
|
|
1000 | |
|
|
1001 | if (defined $AnyEvent::MODEL) { |
|
|
1002 | # AnyEvent already initialised, so load Coro::AnyEvent |
|
|
1003 | require Coro::AnyEvent; |
|
|
1004 | } else { |
|
|
1005 | # AnyEvent not yet initialised, so make sure to load Coro::AnyEvent |
|
|
1006 | # as soon as it is |
|
|
1007 | push @AnyEvent::post_detect, sub { require Coro::AnyEvent }; |
|
|
1008 | } |
|
|
1009 | |
|
|
1010 | =item AnyEvent::postpone { BLOCK } |
|
|
1011 | |
|
|
1012 | Arranges for the block to be executed as soon as possible, but not before |
|
|
1013 | the call itself returns. In practise, the block will be executed just |
|
|
1014 | before the event loop polls for new events, or shortly afterwards. |
|
|
1015 | |
|
|
1016 | This function never returns anything (to make the C<return postpone { ... |
|
|
1017 | }> idiom more useful. |
|
|
1018 | |
|
|
1019 | To understand the usefulness of this function, consider a function that |
|
|
1020 | asynchronously does something for you and returns some transaction |
|
|
1021 | object or guard to let you cancel the operation. For example, |
|
|
1022 | C<AnyEvent::Socket::tcp_connect>: |
|
|
1023 | |
|
|
1024 | # start a conenction attempt unless one is active |
|
|
1025 | $self->{connect_guard} ||= AnyEvent::Socket::tcp_connect "www.example.net", 80, sub { |
|
|
1026 | delete $self->{connect_guard}; |
|
|
1027 | ... |
|
|
1028 | }; |
|
|
1029 | |
|
|
1030 | Imagine that this function could instantly call the callback, for |
|
|
1031 | example, because it detects an obvious error such as a negative port |
|
|
1032 | number. Invoking the callback before the function returns causes problems |
|
|
1033 | however: the callback will be called and will try to delete the guard |
|
|
1034 | object. But since the function hasn't returned yet, there is nothing to |
|
|
1035 | delete. When the function eventually returns it will assign the guard |
|
|
1036 | object to C<< $self->{connect_guard} >>, where it will likely never be |
|
|
1037 | deleted, so the program thinks it is still trying to connect. |
|
|
1038 | |
|
|
1039 | This is where C<AnyEvent::postpone> should be used. Instead of calling the |
|
|
1040 | callback directly on error: |
|
|
1041 | |
|
|
1042 | $cb->(undef), return # signal error to callback, BAD! |
|
|
1043 | if $some_error_condition; |
|
|
1044 | |
|
|
1045 | It should use C<postpone>: |
|
|
1046 | |
|
|
1047 | AnyEvent::postpone { $cb->(undef) }, return # signal error to callback, later |
|
|
1048 | if $some_error_condition; |
|
|
1049 | |
953 | =back |
1050 | =back |
954 | |
1051 | |
955 | =head1 WHAT TO DO IN A MODULE |
1052 | =head1 WHAT TO DO IN A MODULE |
956 | |
1053 | |
957 | As a module author, you should C<use AnyEvent> and call AnyEvent methods |
1054 | As a module author, you should C<use AnyEvent> and call AnyEvent methods |
… | |
… | |
967 | because it will stall the whole program, and the whole point of using |
1064 | because it will stall the whole program, and the whole point of using |
968 | events is to stay interactive. |
1065 | events is to stay interactive. |
969 | |
1066 | |
970 | It is fine, however, to call C<< ->recv >> when the user of your module |
1067 | It is fine, however, to call C<< ->recv >> when the user of your module |
971 | requests it (i.e. if you create a http request object ad have a method |
1068 | requests it (i.e. if you create a http request object ad have a method |
972 | called C<results> that returns the results, it should call C<< ->recv >> |
1069 | called C<results> that returns the results, it may call C<< ->recv >> |
973 | freely, as the user of your module knows what she is doing. always). |
1070 | freely, as the user of your module knows what she is doing. Always). |
974 | |
1071 | |
975 | =head1 WHAT TO DO IN THE MAIN PROGRAM |
1072 | =head1 WHAT TO DO IN THE MAIN PROGRAM |
976 | |
1073 | |
977 | There will always be a single main program - the only place that should |
1074 | There will always be a single main program - the only place that should |
978 | dictate which event model to use. |
1075 | dictate which event model to use. |
979 | |
1076 | |
980 | If it doesn't care, it can just "use AnyEvent" and use it itself, or not |
1077 | If the program is not event-based, it need not do anything special, even |
981 | do anything special (it does not need to be event-based) and let AnyEvent |
1078 | when it depends on a module that uses an AnyEvent. If the program itself |
982 | decide which implementation to chose if some module relies on it. |
1079 | uses AnyEvent, but does not care which event loop is used, all it needs |
|
|
1080 | to do is C<use AnyEvent>. In either case, AnyEvent will choose the best |
|
|
1081 | available loop implementation. |
983 | |
1082 | |
984 | If the main program relies on a specific event model - for example, in |
1083 | If the main program relies on a specific event model - for example, in |
985 | Gtk2 programs you have to rely on the Glib module - you should load the |
1084 | Gtk2 programs you have to rely on the Glib module - you should load the |
986 | event module before loading AnyEvent or any module that uses it: generally |
1085 | event module before loading AnyEvent or any module that uses it: generally |
987 | speaking, you should load it as early as possible. The reason is that |
1086 | speaking, you should load it as early as possible. The reason is that |
988 | modules might create watchers when they are loaded, and AnyEvent will |
1087 | modules might create watchers when they are loaded, and AnyEvent will |
989 | decide on the event model to use as soon as it creates watchers, and it |
1088 | decide on the event model to use as soon as it creates watchers, and it |
990 | might chose the wrong one unless you load the correct one yourself. |
1089 | might choose the wrong one unless you load the correct one yourself. |
991 | |
1090 | |
992 | You can chose to use a pure-perl implementation by loading the |
1091 | You can chose to use a pure-perl implementation by loading the |
993 | C<AnyEvent::Impl::Perl> module, which gives you similar behaviour |
1092 | C<AnyEvent::Loop> module, which gives you similar behaviour |
994 | everywhere, but letting AnyEvent chose the model is generally better. |
1093 | everywhere, but letting AnyEvent chose the model is generally better. |
995 | |
1094 | |
996 | =head2 MAINLOOP EMULATION |
1095 | =head2 MAINLOOP EMULATION |
997 | |
1096 | |
998 | Sometimes (often for short test scripts, or even standalone programs who |
1097 | Sometimes (often for short test scripts, or even standalone programs who |
… | |
… | |
1013 | =head1 OTHER MODULES |
1112 | =head1 OTHER MODULES |
1014 | |
1113 | |
1015 | The following is a non-exhaustive list of additional modules that use |
1114 | The following is a non-exhaustive list of additional modules that use |
1016 | AnyEvent as a client and can therefore be mixed easily with other AnyEvent |
1115 | AnyEvent as a client and can therefore be mixed easily with other AnyEvent |
1017 | modules and other event loops in the same program. Some of the modules |
1116 | modules and other event loops in the same program. Some of the modules |
1018 | come with AnyEvent, most are available via CPAN. |
1117 | come as part of AnyEvent, the others are available via CPAN. |
1019 | |
1118 | |
1020 | =over 4 |
1119 | =over 4 |
1021 | |
1120 | |
1022 | =item L<AnyEvent::Util> |
1121 | =item L<AnyEvent::Util> |
1023 | |
1122 | |
1024 | Contains various utility functions that replace often-used but blocking |
1123 | Contains various utility functions that replace often-used blocking |
1025 | functions such as C<inet_aton> by event-/callback-based versions. |
1124 | functions such as C<inet_aton> with event/callback-based versions. |
1026 | |
1125 | |
1027 | =item L<AnyEvent::Socket> |
1126 | =item L<AnyEvent::Socket> |
1028 | |
1127 | |
1029 | Provides various utility functions for (internet protocol) sockets, |
1128 | Provides various utility functions for (internet protocol) sockets, |
1030 | addresses and name resolution. Also functions to create non-blocking tcp |
1129 | addresses and name resolution. Also functions to create non-blocking tcp |
… | |
… | |
1032 | |
1131 | |
1033 | =item L<AnyEvent::Handle> |
1132 | =item L<AnyEvent::Handle> |
1034 | |
1133 | |
1035 | Provide read and write buffers, manages watchers for reads and writes, |
1134 | Provide read and write buffers, manages watchers for reads and writes, |
1036 | supports raw and formatted I/O, I/O queued and fully transparent and |
1135 | supports raw and formatted I/O, I/O queued and fully transparent and |
1037 | non-blocking SSL/TLS (via L<AnyEvent::TLS>. |
1136 | non-blocking SSL/TLS (via L<AnyEvent::TLS>). |
1038 | |
1137 | |
1039 | =item L<AnyEvent::DNS> |
1138 | =item L<AnyEvent::DNS> |
1040 | |
1139 | |
1041 | Provides rich asynchronous DNS resolver capabilities. |
1140 | Provides rich asynchronous DNS resolver capabilities. |
1042 | |
1141 | |
|
|
1142 | =item L<AnyEvent::HTTP>, L<AnyEvent::IRC>, L<AnyEvent::XMPP>, L<AnyEvent::GPSD>, L<AnyEvent::IGS>, L<AnyEvent::FCP> |
|
|
1143 | |
|
|
1144 | Implement event-based interfaces to the protocols of the same name (for |
|
|
1145 | the curious, IGS is the International Go Server and FCP is the Freenet |
|
|
1146 | Client Protocol). |
|
|
1147 | |
|
|
1148 | =item L<AnyEvent::Handle::UDP> |
|
|
1149 | |
|
|
1150 | Here be danger! |
|
|
1151 | |
|
|
1152 | As Pauli would put it, "Not only is it not right, it's not even wrong!" - |
|
|
1153 | there are so many things wrong with AnyEvent::Handle::UDP, most notably |
|
|
1154 | its use of a stream-based API with a protocol that isn't streamable, that |
|
|
1155 | the only way to improve it is to delete it. |
|
|
1156 | |
|
|
1157 | It features data corruption (but typically only under load) and general |
|
|
1158 | confusion. On top, the author is not only clueless about UDP but also |
|
|
1159 | fact-resistant - some gems of his understanding: "connect doesn't work |
|
|
1160 | with UDP", "UDP packets are not IP packets", "UDP only has datagrams, not |
|
|
1161 | packets", "I don't need to implement proper error checking as UDP doesn't |
|
|
1162 | support error checking" and so on - he doesn't even understand what's |
|
|
1163 | wrong with his module when it is explained to him. |
|
|
1164 | |
1043 | =item L<AnyEvent::HTTP> |
1165 | =item L<AnyEvent::DBI> |
1044 | |
1166 | |
1045 | A simple-to-use HTTP library that is capable of making a lot of concurrent |
1167 | Executes L<DBI> requests asynchronously in a proxy process for you, |
1046 | HTTP requests. |
1168 | notifying you in an event-based way when the operation is finished. |
|
|
1169 | |
|
|
1170 | =item L<AnyEvent::AIO> |
|
|
1171 | |
|
|
1172 | Truly asynchronous (as opposed to non-blocking) I/O, should be in the |
|
|
1173 | toolbox of every event programmer. AnyEvent::AIO transparently fuses |
|
|
1174 | L<IO::AIO> and AnyEvent together, giving AnyEvent access to event-based |
|
|
1175 | file I/O, and much more. |
1047 | |
1176 | |
1048 | =item L<AnyEvent::HTTPD> |
1177 | =item L<AnyEvent::HTTPD> |
1049 | |
1178 | |
1050 | Provides a simple web application server framework. |
1179 | A simple embedded webserver. |
1051 | |
1180 | |
1052 | =item L<AnyEvent::FastPing> |
1181 | =item L<AnyEvent::FastPing> |
1053 | |
1182 | |
1054 | The fastest ping in the west. |
1183 | The fastest ping in the west. |
1055 | |
|
|
1056 | =item L<AnyEvent::DBI> |
|
|
1057 | |
|
|
1058 | Executes L<DBI> requests asynchronously in a proxy process. |
|
|
1059 | |
|
|
1060 | =item L<AnyEvent::AIO> |
|
|
1061 | |
|
|
1062 | Truly asynchronous I/O, should be in the toolbox of every event |
|
|
1063 | programmer. AnyEvent::AIO transparently fuses L<IO::AIO> and AnyEvent |
|
|
1064 | together. |
|
|
1065 | |
|
|
1066 | =item L<AnyEvent::BDB> |
|
|
1067 | |
|
|
1068 | Truly asynchronous Berkeley DB access. AnyEvent::BDB transparently fuses |
|
|
1069 | L<BDB> and AnyEvent together. |
|
|
1070 | |
|
|
1071 | =item L<AnyEvent::GPSD> |
|
|
1072 | |
|
|
1073 | A non-blocking interface to gpsd, a daemon delivering GPS information. |
|
|
1074 | |
|
|
1075 | =item L<AnyEvent::IRC> |
|
|
1076 | |
|
|
1077 | AnyEvent based IRC client module family (replacing the older Net::IRC3). |
|
|
1078 | |
|
|
1079 | =item L<AnyEvent::XMPP> |
|
|
1080 | |
|
|
1081 | AnyEvent based XMPP (Jabber protocol) module family (replacing the older |
|
|
1082 | Net::XMPP2>. |
|
|
1083 | |
|
|
1084 | =item L<AnyEvent::IGS> |
|
|
1085 | |
|
|
1086 | A non-blocking interface to the Internet Go Server protocol (used by |
|
|
1087 | L<App::IGS>). |
|
|
1088 | |
|
|
1089 | =item L<Net::FCP> |
|
|
1090 | |
|
|
1091 | AnyEvent-based implementation of the Freenet Client Protocol, birthplace |
|
|
1092 | of AnyEvent. |
|
|
1093 | |
|
|
1094 | =item L<Event::ExecFlow> |
|
|
1095 | |
|
|
1096 | High level API for event-based execution flow control. |
|
|
1097 | |
1184 | |
1098 | =item L<Coro> |
1185 | =item L<Coro> |
1099 | |
1186 | |
1100 | Has special support for AnyEvent via L<Coro::AnyEvent>. |
1187 | Has special support for AnyEvent via L<Coro::AnyEvent>. |
1101 | |
1188 | |
… | |
… | |
1105 | |
1192 | |
1106 | package AnyEvent; |
1193 | package AnyEvent; |
1107 | |
1194 | |
1108 | # basically a tuned-down version of common::sense |
1195 | # basically a tuned-down version of common::sense |
1109 | sub common_sense { |
1196 | sub common_sense { |
1110 | # no warnings |
1197 | # from common:.sense 3.4 |
1111 | ${^WARNING_BITS} ^= ${^WARNING_BITS}; |
1198 | ${^WARNING_BITS} ^= ${^WARNING_BITS} ^ "\x3c\x3f\x33\x00\x0f\xf0\x0f\xc0\xf0\xfc\x33\x00"; |
1112 | # use strict vars subs |
1199 | # use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl) |
1113 | $^H |= 0x00000600; |
1200 | $^H |= 0x00000600; |
1114 | } |
1201 | } |
1115 | |
1202 | |
1116 | BEGIN { AnyEvent::common_sense } |
1203 | BEGIN { AnyEvent::common_sense } |
1117 | |
1204 | |
1118 | use Carp (); |
1205 | use Carp (); |
1119 | |
1206 | |
1120 | our $VERSION = '5.0'; |
1207 | our $VERSION = '5.34'; |
1121 | our $MODEL; |
1208 | our $MODEL; |
1122 | |
1209 | |
1123 | our $AUTOLOAD; |
1210 | our $AUTOLOAD; |
1124 | our @ISA; |
1211 | our @ISA; |
1125 | |
1212 | |
1126 | our @REGISTRY; |
1213 | our @REGISTRY; |
1127 | |
1214 | |
1128 | our $WIN32; |
|
|
1129 | |
|
|
1130 | our $VERBOSE; |
1215 | our $VERBOSE; |
1131 | |
1216 | |
1132 | BEGIN { |
1217 | BEGIN { |
1133 | eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }"; |
1218 | require "AnyEvent/constants.pl"; |
|
|
1219 | |
1134 | eval "sub TAINT(){ " . (${^TAINT}*1) . " }"; |
1220 | eval "sub TAINT (){" . (${^TAINT}*1) . "}"; |
1135 | |
1221 | |
1136 | delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV} |
1222 | delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV} |
1137 | if ${^TAINT}; |
1223 | if ${^TAINT}; |
1138 | |
1224 | |
1139 | $VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1; |
1225 | $VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1; |
… | |
… | |
1151 | $ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6"; |
1237 | $ENV{PERL_ANYEVENT_PROTOCOLS} || "ipv4,ipv6"; |
1152 | } |
1238 | } |
1153 | |
1239 | |
1154 | my @models = ( |
1240 | my @models = ( |
1155 | [EV:: => AnyEvent::Impl::EV:: , 1], |
1241 | [EV:: => AnyEvent::Impl::EV:: , 1], |
1156 | [AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl:: , 1], |
1242 | [AnyEvent::Loop:: => AnyEvent::Impl::Perl:: , 1], |
1157 | # everything below here will not (normally) be autoprobed |
1243 | # everything below here will not (normally) be autoprobed |
1158 | # as the pureperl backend should work everywhere |
1244 | # as the pure perl backend should work everywhere |
1159 | # and is usually faster |
1245 | # and is usually faster |
1160 | [Event:: => AnyEvent::Impl::Event::, 1], |
1246 | [Event:: => AnyEvent::Impl::Event::, 1], |
1161 | [Glib:: => AnyEvent::Impl::Glib:: , 1], # becomes extremely slow with many watchers |
1247 | [Glib:: => AnyEvent::Impl::Glib:: , 1], # becomes extremely slow with many watchers |
1162 | [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy |
1248 | [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy |
1163 | [Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package |
1249 | [Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package |
1164 | [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles |
1250 | [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles |
1165 | [Qt:: => AnyEvent::Impl::Qt::], # requires special main program |
1251 | [Qt:: => AnyEvent::Impl::Qt::], # requires special main program |
1166 | [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza |
1252 | [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza |
1167 | [Wx:: => AnyEvent::Impl::POE::], |
1253 | [Wx:: => AnyEvent::Impl::POE::], |
1168 | [Prima:: => AnyEvent::Impl::POE::], |
1254 | [Prima:: => AnyEvent::Impl::POE::], |
1169 | # IO::Async is just too broken - we would need workarounds for its |
|
|
1170 | # byzantine signal and broken child handling, among others. |
|
|
1171 | # IO::Async is rather hard to detect, as it doesn't have any |
|
|
1172 | # obvious default class. |
|
|
1173 | [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program |
|
|
1174 | [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program |
1255 | [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], |
1175 | [IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program |
1256 | [Cocoa::EventLoop:: => AnyEvent::Impl::Cocoa::], |
1176 | [AnyEvent::Impl::IOAsync:: => AnyEvent::Impl::IOAsync::], # requires special main program |
1257 | [FLTK:: => AnyEvent::Impl::FLTK::], |
1177 | ); |
1258 | ); |
1178 | |
1259 | |
1179 | our %method = map +($_ => 1), |
1260 | our %method = map +($_ => 1), |
1180 | qw(io timer time now now_update signal child idle condvar one_event DESTROY); |
1261 | qw(io timer time now now_update signal child idle condvar DESTROY); |
1181 | |
1262 | |
1182 | our @post_detect; |
1263 | our @post_detect; |
1183 | |
1264 | |
1184 | sub post_detect(&) { |
1265 | sub post_detect(&) { |
1185 | my ($cb) = @_; |
1266 | my ($cb) = @_; |
1186 | |
1267 | |
1187 | if ($MODEL) { |
|
|
1188 | $cb->(); |
|
|
1189 | |
|
|
1190 | undef |
|
|
1191 | } else { |
|
|
1192 | push @post_detect, $cb; |
1268 | push @post_detect, $cb; |
1193 | |
1269 | |
1194 | defined wantarray |
1270 | defined wantarray |
1195 | ? bless \$cb, "AnyEvent::Util::postdetect" |
1271 | ? bless \$cb, "AnyEvent::Util::postdetect" |
1196 | : () |
1272 | : () |
1197 | } |
|
|
1198 | } |
1273 | } |
1199 | |
1274 | |
1200 | sub AnyEvent::Util::postdetect::DESTROY { |
1275 | sub AnyEvent::Util::postdetect::DESTROY { |
1201 | @post_detect = grep $_ != ${$_[0]}, @post_detect; |
1276 | @post_detect = grep $_ != ${$_[0]}, @post_detect; |
1202 | } |
1277 | } |
1203 | |
1278 | |
1204 | sub detect() { |
1279 | sub detect() { |
|
|
1280 | # free some memory |
|
|
1281 | *detect = sub () { $MODEL }; |
|
|
1282 | |
|
|
1283 | local $!; # for good measure |
|
|
1284 | local $SIG{__DIE__}; |
|
|
1285 | |
|
|
1286 | if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) { |
|
|
1287 | my $model = "AnyEvent::Impl::$1"; |
|
|
1288 | if (eval "require $model") { |
|
|
1289 | $MODEL = $model; |
|
|
1290 | warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2; |
|
|
1291 | } else { |
|
|
1292 | warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE; |
|
|
1293 | } |
|
|
1294 | } |
|
|
1295 | |
|
|
1296 | # check for already loaded models |
1205 | unless ($MODEL) { |
1297 | unless ($MODEL) { |
1206 | local $SIG{__DIE__}; |
1298 | for (@REGISTRY, @models) { |
1207 | |
1299 | my ($package, $model) = @$_; |
1208 | if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) { |
1300 | if (${"$package\::VERSION"} > 0) { |
1209 | my $model = "AnyEvent::Impl::$1"; |
|
|
1210 | if (eval "require $model") { |
1301 | if (eval "require $model") { |
1211 | $MODEL = $model; |
1302 | $MODEL = $model; |
1212 | warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2; |
1303 | warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2; |
1213 | } else { |
1304 | last; |
1214 | warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE; |
1305 | } |
1215 | } |
1306 | } |
1216 | } |
1307 | } |
1217 | |
1308 | |
1218 | # check for already loaded models |
|
|
1219 | unless ($MODEL) { |
1309 | unless ($MODEL) { |
|
|
1310 | # try to autoload a model |
1220 | for (@REGISTRY, @models) { |
1311 | for (@REGISTRY, @models) { |
1221 | my ($package, $model) = @$_; |
1312 | my ($package, $model, $autoload) = @$_; |
|
|
1313 | if ( |
|
|
1314 | $autoload |
|
|
1315 | and eval "require $package" |
1222 | if (${"$package\::VERSION"} > 0) { |
1316 | and ${"$package\::VERSION"} > 0 |
1223 | if (eval "require $model") { |
1317 | and eval "require $model" |
|
|
1318 | ) { |
1224 | $MODEL = $model; |
1319 | $MODEL = $model; |
1225 | warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2; |
1320 | warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2; |
1226 | last; |
1321 | last; |
1227 | } |
|
|
1228 | } |
1322 | } |
1229 | } |
1323 | } |
1230 | |
1324 | |
1231 | unless ($MODEL) { |
|
|
1232 | # try to autoload a model |
|
|
1233 | for (@REGISTRY, @models) { |
|
|
1234 | my ($package, $model, $autoload) = @$_; |
|
|
1235 | if ( |
|
|
1236 | $autoload |
|
|
1237 | and eval "require $package" |
|
|
1238 | and ${"$package\::VERSION"} > 0 |
|
|
1239 | and eval "require $model" |
|
|
1240 | ) { |
|
|
1241 | $MODEL = $model; |
|
|
1242 | warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2; |
|
|
1243 | last; |
|
|
1244 | } |
|
|
1245 | } |
|
|
1246 | |
|
|
1247 | $MODEL |
1325 | $MODEL |
1248 | or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.\n"; |
1326 | or die "AnyEvent: backend autodetection failed - did you properly install AnyEvent?\n"; |
1249 | } |
|
|
1250 | } |
1327 | } |
1251 | |
|
|
1252 | push @{"$MODEL\::ISA"}, "AnyEvent::Base"; |
|
|
1253 | |
|
|
1254 | unshift @ISA, $MODEL; |
|
|
1255 | |
|
|
1256 | require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT}; |
|
|
1257 | |
|
|
1258 | (shift @post_detect)->() while @post_detect; |
|
|
1259 | } |
1328 | } |
|
|
1329 | |
|
|
1330 | @models = (); # free probe data |
|
|
1331 | |
|
|
1332 | push @{"$MODEL\::ISA"}, "AnyEvent::Base"; |
|
|
1333 | unshift @ISA, $MODEL; |
|
|
1334 | |
|
|
1335 | # now nuke some methods that are overridden by the backend. |
|
|
1336 | # SUPER is not allowed. |
|
|
1337 | for (qw(time signal child idle)) { |
|
|
1338 | undef &{"AnyEvent::Base::$_"} |
|
|
1339 | if defined &{"$MODEL\::$_"}; |
|
|
1340 | } |
|
|
1341 | |
|
|
1342 | if ($ENV{PERL_ANYEVENT_STRICT}) { |
|
|
1343 | eval { require AnyEvent::Strict }; |
|
|
1344 | warn "AnyEvent: cannot load AnyEvent::Strict: $@" |
|
|
1345 | if $@ && $VERBOSE; |
|
|
1346 | } |
|
|
1347 | |
|
|
1348 | (shift @post_detect)->() while @post_detect; |
|
|
1349 | |
|
|
1350 | *post_detect = sub(&) { |
|
|
1351 | shift->(); |
|
|
1352 | |
|
|
1353 | undef |
|
|
1354 | }; |
1260 | |
1355 | |
1261 | $MODEL |
1356 | $MODEL |
1262 | } |
1357 | } |
1263 | |
1358 | |
1264 | sub AUTOLOAD { |
1359 | sub AUTOLOAD { |
1265 | (my $func = $AUTOLOAD) =~ s/.*://; |
1360 | (my $func = $AUTOLOAD) =~ s/.*://; |
1266 | |
1361 | |
1267 | $method{$func} |
1362 | $method{$func} |
1268 | or Carp::croak "$func: not a valid method for AnyEvent objects"; |
1363 | or Carp::croak "$func: not a valid AnyEvent class method"; |
1269 | |
1364 | |
1270 | detect unless $MODEL; |
1365 | detect; |
1271 | |
1366 | |
1272 | my $class = shift; |
1367 | my $class = shift; |
1273 | $class->$func (@_); |
1368 | $class->$func (@_); |
|
|
1369 | } |
|
|
1370 | |
|
|
1371 | our $POSTPONE_W; |
|
|
1372 | our @POSTPONE; |
|
|
1373 | |
|
|
1374 | sub _postpone_exec { |
|
|
1375 | undef $POSTPONE_W; |
|
|
1376 | (pop @POSTPONE)->() |
|
|
1377 | while @POSTPONE; |
|
|
1378 | } |
|
|
1379 | |
|
|
1380 | sub postpone(&) { |
|
|
1381 | push @POSTPONE, shift; |
|
|
1382 | |
|
|
1383 | $POSTPONE_W ||= AE::timer (0, 0, \&_postpone_exec); |
|
|
1384 | |
|
|
1385 | () |
1274 | } |
1386 | } |
1275 | |
1387 | |
1276 | # utility function to dup a filehandle. this is used by many backends |
1388 | # utility function to dup a filehandle. this is used by many backends |
1277 | # to support binding more than one watcher per filehandle (they usually |
1389 | # to support binding more than one watcher per filehandle (they usually |
1278 | # allow only one watcher per fd, so we dup it to get a different one). |
1390 | # allow only one watcher per fd, so we dup it to get a different one). |
… | |
… | |
1292 | |
1404 | |
1293 | =head1 SIMPLIFIED AE API |
1405 | =head1 SIMPLIFIED AE API |
1294 | |
1406 | |
1295 | Starting with version 5.0, AnyEvent officially supports a second, much |
1407 | Starting with version 5.0, AnyEvent officially supports a second, much |
1296 | simpler, API that is designed to reduce the calling, typing and memory |
1408 | simpler, API that is designed to reduce the calling, typing and memory |
1297 | overhead. |
1409 | overhead by using function call syntax and a fixed number of parameters. |
1298 | |
1410 | |
1299 | See the L<AE> manpage for details. |
1411 | See the L<AE> manpage for details. |
1300 | |
1412 | |
1301 | =cut |
1413 | =cut |
1302 | |
1414 | |
1303 | package AE; |
1415 | package AE; |
1304 | |
1416 | |
1305 | our $VERSION = $AnyEvent::VERSION; |
1417 | our $VERSION = $AnyEvent::VERSION; |
|
|
1418 | |
|
|
1419 | # fall back to the main API by default - backends and AnyEvent::Base |
|
|
1420 | # implementations can overwrite these. |
1306 | |
1421 | |
1307 | sub io($$$) { |
1422 | sub io($$$) { |
1308 | AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2]) |
1423 | AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2]) |
1309 | } |
1424 | } |
1310 | |
1425 | |
… | |
… | |
1338 | |
1453 | |
1339 | sub time() { |
1454 | sub time() { |
1340 | AnyEvent->time |
1455 | AnyEvent->time |
1341 | } |
1456 | } |
1342 | |
1457 | |
|
|
1458 | *postpone = \&AnyEvent::postpone; |
|
|
1459 | |
1343 | package AnyEvent::Base; |
1460 | package AnyEvent::Base; |
1344 | |
1461 | |
1345 | # default implementations for many methods |
1462 | # default implementations for many methods |
1346 | |
1463 | |
1347 | sub _time { |
1464 | sub time { |
|
|
1465 | eval q{ # poor man's autoloading {} |
1348 | # probe for availability of Time::HiRes |
1466 | # probe for availability of Time::HiRes |
1349 | if (eval "use Time::HiRes (); Time::HiRes::time (); 1") { |
1467 | if (eval "use Time::HiRes (); Time::HiRes::time (); 1") { |
1350 | warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8; |
1468 | warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8; |
1351 | *_time = \&Time::HiRes::time; |
1469 | *AE::time = \&Time::HiRes::time; |
1352 | # if (eval "use POSIX (); (POSIX::times())... |
1470 | # if (eval "use POSIX (); (POSIX::times())... |
1353 | } else { |
1471 | } else { |
1354 | warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE; |
1472 | warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE; |
1355 | *_time = sub { time }; # epic fail |
1473 | *AE::time = sub (){ time }; # epic fail |
|
|
1474 | } |
|
|
1475 | |
|
|
1476 | *time = sub { AE::time }; # different prototypes |
1356 | } |
1477 | }; |
|
|
1478 | die if $@; |
1357 | |
1479 | |
1358 | &_time |
1480 | &time |
1359 | } |
1481 | } |
1360 | |
1482 | |
1361 | sub time { _time } |
1483 | *now = \&time; |
1362 | sub now { _time } |
1484 | |
1363 | sub now_update { } |
1485 | sub now_update { } |
1364 | |
1486 | |
|
|
1487 | sub _poll { |
|
|
1488 | Carp::croak "$AnyEvent::MODEL does not support blocking waits. Caught"; |
|
|
1489 | } |
|
|
1490 | |
1365 | # default implementation for ->condvar |
1491 | # default implementation for ->condvar |
|
|
1492 | # in fact, the default should not be overwritten |
1366 | |
1493 | |
1367 | sub condvar { |
1494 | sub condvar { |
|
|
1495 | eval q{ # poor man's autoloading {} |
|
|
1496 | *condvar = sub { |
1368 | bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar" |
1497 | bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar" |
|
|
1498 | }; |
|
|
1499 | |
|
|
1500 | *AE::cv = sub (;&) { |
|
|
1501 | bless { @_ ? (_ae_cb => shift) : () }, "AnyEvent::CondVar" |
|
|
1502 | }; |
|
|
1503 | }; |
|
|
1504 | die if $@; |
|
|
1505 | |
|
|
1506 | &condvar |
1369 | } |
1507 | } |
1370 | |
1508 | |
1371 | # default implementation for ->signal |
1509 | # default implementation for ->signal |
1372 | |
1510 | |
1373 | our $HAVE_ASYNC_INTERRUPT; |
1511 | our $HAVE_ASYNC_INTERRUPT; |
1374 | |
1512 | |
1375 | sub _have_async_interrupt() { |
1513 | sub _have_async_interrupt() { |
1376 | $HAVE_ASYNC_INTERRUPT = 1*(!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT} |
1514 | $HAVE_ASYNC_INTERRUPT = 1*(!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT} |
1377 | && eval "use Async::Interrupt 1.0 (); 1") |
1515 | && eval "use Async::Interrupt 1.02 (); 1") |
1378 | unless defined $HAVE_ASYNC_INTERRUPT; |
1516 | unless defined $HAVE_ASYNC_INTERRUPT; |
1379 | |
1517 | |
1380 | $HAVE_ASYNC_INTERRUPT |
1518 | $HAVE_ASYNC_INTERRUPT |
1381 | } |
1519 | } |
1382 | |
1520 | |
1383 | our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO); |
1521 | our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO); |
1384 | our (%SIG_ASY, %SIG_ASY_W); |
1522 | our (%SIG_ASY, %SIG_ASY_W); |
1385 | our ($SIG_COUNT, $SIG_TW); |
1523 | our ($SIG_COUNT, $SIG_TW); |
1386 | |
1524 | |
1387 | sub _signal_exec { |
|
|
1388 | $HAVE_ASYNC_INTERRUPT |
|
|
1389 | ? $SIGPIPE_R->drain |
|
|
1390 | : sysread $SIGPIPE_R, my $dummy, 9; |
|
|
1391 | |
|
|
1392 | while (%SIG_EV) { |
|
|
1393 | for (keys %SIG_EV) { |
|
|
1394 | delete $SIG_EV{$_}; |
|
|
1395 | $_->() for values %{ $SIG_CB{$_} || {} }; |
|
|
1396 | } |
|
|
1397 | } |
|
|
1398 | } |
|
|
1399 | |
|
|
1400 | # install a dummy wakeup watcher to reduce signal catching latency |
1525 | # install a dummy wakeup watcher to reduce signal catching latency |
|
|
1526 | # used by Impls |
1401 | sub _sig_add() { |
1527 | sub _sig_add() { |
1402 | unless ($SIG_COUNT++) { |
1528 | unless ($SIG_COUNT++) { |
1403 | # try to align timer on a full-second boundary, if possible |
1529 | # try to align timer on a full-second boundary, if possible |
1404 | my $NOW = AE::now; |
1530 | my $NOW = AE::now; |
1405 | |
1531 | |
… | |
… | |
1415 | undef $SIG_TW |
1541 | undef $SIG_TW |
1416 | unless --$SIG_COUNT; |
1542 | unless --$SIG_COUNT; |
1417 | } |
1543 | } |
1418 | |
1544 | |
1419 | our $_sig_name_init; $_sig_name_init = sub { |
1545 | our $_sig_name_init; $_sig_name_init = sub { |
1420 | eval q{ # poor man's autoloading |
1546 | eval q{ # poor man's autoloading {} |
1421 | undef $_sig_name_init; |
1547 | undef $_sig_name_init; |
1422 | |
1548 | |
1423 | if (_have_async_interrupt) { |
1549 | if (_have_async_interrupt) { |
1424 | *sig2num = \&Async::Interrupt::sig2num; |
1550 | *sig2num = \&Async::Interrupt::sig2num; |
1425 | *sig2name = \&Async::Interrupt::sig2name; |
1551 | *sig2name = \&Async::Interrupt::sig2name; |
… | |
… | |
1457 | $SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec; |
1583 | $SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec; |
1458 | |
1584 | |
1459 | } else { |
1585 | } else { |
1460 | warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8; |
1586 | warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8; |
1461 | |
1587 | |
1462 | require Fcntl; |
|
|
1463 | |
|
|
1464 | if (AnyEvent::WIN32) { |
1588 | if (AnyEvent::WIN32) { |
1465 | require AnyEvent::Util; |
1589 | require AnyEvent::Util; |
1466 | |
1590 | |
1467 | ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe (); |
1591 | ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe (); |
1468 | AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R; |
1592 | AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R; |
1469 | AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case |
1593 | AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case |
1470 | } else { |
1594 | } else { |
1471 | pipe $SIGPIPE_R, $SIGPIPE_W; |
1595 | pipe $SIGPIPE_R, $SIGPIPE_W; |
1472 | fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R; |
1596 | fcntl $SIGPIPE_R, AnyEvent::F_SETFL, AnyEvent::O_NONBLOCK if $SIGPIPE_R; |
1473 | fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case |
1597 | fcntl $SIGPIPE_W, AnyEvent::F_SETFL, AnyEvent::O_NONBLOCK if $SIGPIPE_W; # just in case |
1474 | |
1598 | |
1475 | # not strictly required, as $^F is normally 2, but let's make sure... |
1599 | # not strictly required, as $^F is normally 2, but let's make sure... |
1476 | fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; |
1600 | fcntl $SIGPIPE_R, AnyEvent::F_SETFD, AnyEvent::FD_CLOEXEC; |
1477 | fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; |
1601 | fcntl $SIGPIPE_W, AnyEvent::F_SETFD, AnyEvent::FD_CLOEXEC; |
1478 | } |
1602 | } |
1479 | |
1603 | |
1480 | $SIGPIPE_R |
1604 | $SIGPIPE_R |
1481 | or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n"; |
1605 | or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n"; |
1482 | |
1606 | |
1483 | $SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec; |
1607 | $SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec; |
1484 | } |
1608 | } |
1485 | |
1609 | |
1486 | *signal = sub { |
1610 | *signal = $HAVE_ASYNC_INTERRUPT |
|
|
1611 | ? sub { |
1487 | my (undef, %arg) = @_; |
1612 | my (undef, %arg) = @_; |
1488 | |
1613 | |
1489 | my $signal = uc $arg{signal} |
|
|
1490 | or Carp::croak "required option 'signal' is missing"; |
|
|
1491 | |
|
|
1492 | if ($HAVE_ASYNC_INTERRUPT) { |
|
|
1493 | # async::interrupt |
1614 | # async::interrupt |
1494 | |
|
|
1495 | $signal = sig2num $signal; |
1615 | my $signal = sig2num $arg{signal}; |
1496 | $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; |
1616 | $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; |
1497 | |
1617 | |
1498 | $SIG_ASY{$signal} ||= new Async::Interrupt |
1618 | $SIG_ASY{$signal} ||= new Async::Interrupt |
1499 | cb => sub { undef $SIG_EV{$signal} }, |
1619 | cb => sub { undef $SIG_EV{$signal} }, |
1500 | signal => $signal, |
1620 | signal => $signal, |
1501 | pipe => [$SIGPIPE_R->filenos], |
1621 | pipe => [$SIGPIPE_R->filenos], |
1502 | pipe_autodrain => 0, |
1622 | pipe_autodrain => 0, |
1503 | ; |
1623 | ; |
1504 | |
1624 | |
1505 | } else { |
1625 | bless [$signal, $arg{cb}], "AnyEvent::Base::signal" |
|
|
1626 | } |
|
|
1627 | : sub { |
|
|
1628 | my (undef, %arg) = @_; |
|
|
1629 | |
1506 | # pure perl |
1630 | # pure perl |
1507 | |
|
|
1508 | # AE::Util has been loaded in signal |
|
|
1509 | $signal = sig2name $signal; |
1631 | my $signal = sig2name $arg{signal}; |
1510 | $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; |
1632 | $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; |
1511 | |
1633 | |
1512 | $SIG{$signal} ||= sub { |
1634 | $SIG{$signal} ||= sub { |
1513 | local $!; |
1635 | local $!; |
1514 | syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV; |
1636 | syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV; |
1515 | undef $SIG_EV{$signal}; |
1637 | undef $SIG_EV{$signal}; |
1516 | }; |
1638 | }; |
1517 | |
1639 | |
1518 | # can't do signal processing without introducing races in pure perl, |
1640 | # can't do signal processing without introducing races in pure perl, |
1519 | # so limit the signal latency. |
1641 | # so limit the signal latency. |
1520 | _sig_add; |
1642 | _sig_add; |
1521 | } |
|
|
1522 | |
1643 | |
1523 | bless [$signal, $arg{cb}], "AnyEvent::Base::signal" |
1644 | bless [$signal, $arg{cb}], "AnyEvent::Base::signal" |
|
|
1645 | } |
1524 | }; |
1646 | ; |
1525 | |
1647 | |
1526 | *AnyEvent::Base::signal::DESTROY = sub { |
1648 | *AnyEvent::Base::signal::DESTROY = sub { |
1527 | my ($signal, $cb) = @{$_[0]}; |
1649 | my ($signal, $cb) = @{$_[0]}; |
1528 | |
1650 | |
1529 | _sig_del; |
1651 | _sig_del; |
… | |
… | |
1536 | # print weird messages, or just unconditionally exit |
1658 | # print weird messages, or just unconditionally exit |
1537 | # instead of getting the default action. |
1659 | # instead of getting the default action. |
1538 | undef $SIG{$signal} |
1660 | undef $SIG{$signal} |
1539 | unless keys %{ $SIG_CB{$signal} }; |
1661 | unless keys %{ $SIG_CB{$signal} }; |
1540 | }; |
1662 | }; |
|
|
1663 | |
|
|
1664 | *_signal_exec = sub { |
|
|
1665 | $HAVE_ASYNC_INTERRUPT |
|
|
1666 | ? $SIGPIPE_R->drain |
|
|
1667 | : sysread $SIGPIPE_R, (my $dummy), 9; |
|
|
1668 | |
|
|
1669 | while (%SIG_EV) { |
|
|
1670 | for (keys %SIG_EV) { |
|
|
1671 | delete $SIG_EV{$_}; |
|
|
1672 | $_->() for values %{ $SIG_CB{$_} || {} }; |
|
|
1673 | } |
|
|
1674 | } |
|
|
1675 | }; |
1541 | }; |
1676 | }; |
1542 | die if $@; |
1677 | die if $@; |
|
|
1678 | |
1543 | &signal |
1679 | &signal |
1544 | } |
1680 | } |
1545 | |
1681 | |
1546 | # default implementation for ->child |
1682 | # default implementation for ->child |
1547 | |
1683 | |
1548 | our %PID_CB; |
1684 | our %PID_CB; |
1549 | our $CHLD_W; |
1685 | our $CHLD_W; |
1550 | our $CHLD_DELAY_W; |
1686 | our $CHLD_DELAY_W; |
1551 | our $WNOHANG; |
|
|
1552 | |
1687 | |
|
|
1688 | # used by many Impl's |
1553 | sub _emit_childstatus($$) { |
1689 | sub _emit_childstatus($$) { |
1554 | my (undef, $rpid, $rstatus) = @_; |
1690 | my (undef, $rpid, $rstatus) = @_; |
1555 | |
1691 | |
1556 | $_->($rpid, $rstatus) |
1692 | $_->($rpid, $rstatus) |
1557 | for values %{ $PID_CB{$rpid} || {} }, |
1693 | for values %{ $PID_CB{$rpid} || {} }, |
1558 | values %{ $PID_CB{0} || {} }; |
1694 | values %{ $PID_CB{0} || {} }; |
1559 | } |
1695 | } |
1560 | |
1696 | |
1561 | sub _sigchld { |
|
|
1562 | my $pid; |
|
|
1563 | |
|
|
1564 | AnyEvent->_emit_childstatus ($pid, $?) |
|
|
1565 | while ($pid = waitpid -1, $WNOHANG) > 0; |
|
|
1566 | } |
|
|
1567 | |
|
|
1568 | sub child { |
1697 | sub child { |
|
|
1698 | eval q{ # poor man's autoloading {} |
|
|
1699 | *_sigchld = sub { |
|
|
1700 | my $pid; |
|
|
1701 | |
|
|
1702 | AnyEvent->_emit_childstatus ($pid, $?) |
|
|
1703 | while ($pid = waitpid -1, WNOHANG) > 0; |
|
|
1704 | }; |
|
|
1705 | |
|
|
1706 | *child = sub { |
1569 | my (undef, %arg) = @_; |
1707 | my (undef, %arg) = @_; |
1570 | |
1708 | |
1571 | defined (my $pid = $arg{pid} + 0) |
1709 | my $pid = $arg{pid}; |
1572 | or Carp::croak "required option 'pid' is missing"; |
1710 | my $cb = $arg{cb}; |
1573 | |
1711 | |
1574 | $PID_CB{$pid}{$arg{cb}} = $arg{cb}; |
1712 | $PID_CB{$pid}{$cb+0} = $cb; |
1575 | |
1713 | |
1576 | # WNOHANG is almost cetrainly 1 everywhere |
|
|
1577 | $WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/ |
|
|
1578 | ? 1 |
|
|
1579 | : eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1; |
|
|
1580 | |
|
|
1581 | unless ($CHLD_W) { |
1714 | unless ($CHLD_W) { |
1582 | $CHLD_W = AE::signal CHLD => \&_sigchld; |
1715 | $CHLD_W = AE::signal CHLD => \&_sigchld; |
1583 | # child could be a zombie already, so make at least one round |
1716 | # child could be a zombie already, so make at least one round |
1584 | &_sigchld; |
1717 | &_sigchld; |
1585 | } |
1718 | } |
1586 | |
1719 | |
1587 | bless [$pid, $arg{cb}], "AnyEvent::Base::child" |
1720 | bless [$pid, $cb+0], "AnyEvent::Base::child" |
1588 | } |
1721 | }; |
1589 | |
1722 | |
1590 | sub AnyEvent::Base::child::DESTROY { |
1723 | *AnyEvent::Base::child::DESTROY = sub { |
1591 | my ($pid, $cb) = @{$_[0]}; |
1724 | my ($pid, $icb) = @{$_[0]}; |
1592 | |
1725 | |
1593 | delete $PID_CB{$pid}{$cb}; |
1726 | delete $PID_CB{$pid}{$icb}; |
1594 | delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} }; |
1727 | delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} }; |
1595 | |
1728 | |
1596 | undef $CHLD_W unless keys %PID_CB; |
1729 | undef $CHLD_W unless keys %PID_CB; |
|
|
1730 | }; |
|
|
1731 | }; |
|
|
1732 | die if $@; |
|
|
1733 | |
|
|
1734 | &child |
1597 | } |
1735 | } |
1598 | |
1736 | |
1599 | # idle emulation is done by simply using a timer, regardless |
1737 | # idle emulation is done by simply using a timer, regardless |
1600 | # of whether the process is idle or not, and not letting |
1738 | # of whether the process is idle or not, and not letting |
1601 | # the callback use more than 50% of the time. |
1739 | # the callback use more than 50% of the time. |
1602 | sub idle { |
1740 | sub idle { |
|
|
1741 | eval q{ # poor man's autoloading {} |
|
|
1742 | *idle = sub { |
1603 | my (undef, %arg) = @_; |
1743 | my (undef, %arg) = @_; |
1604 | |
1744 | |
1605 | my ($cb, $w, $rcb) = $arg{cb}; |
1745 | my ($cb, $w, $rcb) = $arg{cb}; |
1606 | |
1746 | |
1607 | $rcb = sub { |
1747 | $rcb = sub { |
1608 | if ($cb) { |
1748 | if ($cb) { |
1609 | $w = _time; |
1749 | $w = _time; |
1610 | &$cb; |
1750 | &$cb; |
1611 | $w = _time - $w; |
1751 | $w = _time - $w; |
1612 | |
1752 | |
1613 | # never use more then 50% of the time for the idle watcher, |
1753 | # never use more then 50% of the time for the idle watcher, |
1614 | # within some limits |
1754 | # within some limits |
1615 | $w = 0.0001 if $w < 0.0001; |
1755 | $w = 0.0001 if $w < 0.0001; |
1616 | $w = 5 if $w > 5; |
1756 | $w = 5 if $w > 5; |
1617 | |
1757 | |
1618 | $w = AE::timer $w, 0, $rcb; |
1758 | $w = AE::timer $w, 0, $rcb; |
1619 | } else { |
1759 | } else { |
1620 | # clean up... |
1760 | # clean up... |
1621 | undef $w; |
1761 | undef $w; |
1622 | undef $rcb; |
1762 | undef $rcb; |
|
|
1763 | } |
|
|
1764 | }; |
|
|
1765 | |
|
|
1766 | $w = AE::timer 0.05, 0, $rcb; |
|
|
1767 | |
|
|
1768 | bless \\$cb, "AnyEvent::Base::idle" |
1623 | } |
1769 | }; |
|
|
1770 | |
|
|
1771 | *AnyEvent::Base::idle::DESTROY = sub { |
|
|
1772 | undef $${$_[0]}; |
|
|
1773 | }; |
1624 | }; |
1774 | }; |
|
|
1775 | die if $@; |
1625 | |
1776 | |
1626 | $w = AE::timer 0.05, 0, $rcb; |
1777 | &idle |
1627 | |
|
|
1628 | bless \\$cb, "AnyEvent::Base::idle" |
|
|
1629 | } |
|
|
1630 | |
|
|
1631 | sub AnyEvent::Base::idle::DESTROY { |
|
|
1632 | undef $${$_[0]}; |
|
|
1633 | } |
1778 | } |
1634 | |
1779 | |
1635 | package AnyEvent::CondVar; |
1780 | package AnyEvent::CondVar; |
1636 | |
1781 | |
1637 | our @ISA = AnyEvent::CondVar::Base::; |
1782 | our @ISA = AnyEvent::CondVar::Base::; |
|
|
1783 | |
|
|
1784 | # only to be used for subclassing |
|
|
1785 | sub new { |
|
|
1786 | my $class = shift; |
|
|
1787 | bless AnyEvent->condvar (@_), $class |
|
|
1788 | } |
1638 | |
1789 | |
1639 | package AnyEvent::CondVar::Base; |
1790 | package AnyEvent::CondVar::Base; |
1640 | |
1791 | |
1641 | #use overload |
1792 | #use overload |
1642 | # '&{}' => sub { my $self = shift; sub { $self->send (@_) } }, |
1793 | # '&{}' => sub { my $self = shift; sub { $self->send (@_) } }, |
… | |
… | |
1652 | |
1803 | |
1653 | sub _send { |
1804 | sub _send { |
1654 | # nop |
1805 | # nop |
1655 | } |
1806 | } |
1656 | |
1807 | |
|
|
1808 | sub _wait { |
|
|
1809 | AnyEvent->_poll until $_[0]{_ae_sent}; |
|
|
1810 | } |
|
|
1811 | |
1657 | sub send { |
1812 | sub send { |
1658 | my $cv = shift; |
1813 | my $cv = shift; |
1659 | $cv->{_ae_sent} = [@_]; |
1814 | $cv->{_ae_sent} = [@_]; |
1660 | (delete $cv->{_ae_cb})->($cv) if $cv->{_ae_cb}; |
1815 | (delete $cv->{_ae_cb})->($cv) if $cv->{_ae_cb}; |
1661 | $cv->_send; |
1816 | $cv->_send; |
… | |
… | |
1668 | |
1823 | |
1669 | sub ready { |
1824 | sub ready { |
1670 | $_[0]{_ae_sent} |
1825 | $_[0]{_ae_sent} |
1671 | } |
1826 | } |
1672 | |
1827 | |
1673 | sub _wait { |
|
|
1674 | $WAITING |
|
|
1675 | and !$_[0]{_ae_sent} |
|
|
1676 | and Carp::croak "AnyEvent::CondVar: recursive blocking wait detected"; |
|
|
1677 | |
|
|
1678 | local $WAITING = 1; |
|
|
1679 | AnyEvent->one_event while !$_[0]{_ae_sent}; |
|
|
1680 | } |
|
|
1681 | |
|
|
1682 | sub recv { |
1828 | sub recv { |
|
|
1829 | unless ($_[0]{_ae_sent}) { |
|
|
1830 | $WAITING |
|
|
1831 | and Carp::croak "AnyEvent::CondVar: recursive blocking wait attempted"; |
|
|
1832 | |
|
|
1833 | local $WAITING = 1; |
1683 | $_[0]->_wait; |
1834 | $_[0]->_wait; |
|
|
1835 | } |
1684 | |
1836 | |
1685 | Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak}; |
1837 | $_[0]{_ae_croak} |
1686 | wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0] |
1838 | and Carp::croak $_[0]{_ae_croak}; |
|
|
1839 | |
|
|
1840 | wantarray |
|
|
1841 | ? @{ $_[0]{_ae_sent} } |
|
|
1842 | : $_[0]{_ae_sent}[0] |
1687 | } |
1843 | } |
1688 | |
1844 | |
1689 | sub cb { |
1845 | sub cb { |
1690 | my $cv = shift; |
1846 | my $cv = shift; |
1691 | |
1847 | |
… | |
… | |
1707 | &{ $_[0]{_ae_end_cb} || sub { $_[0]->send } }; |
1863 | &{ $_[0]{_ae_end_cb} || sub { $_[0]->send } }; |
1708 | } |
1864 | } |
1709 | |
1865 | |
1710 | # undocumented/compatibility with pre-3.4 |
1866 | # undocumented/compatibility with pre-3.4 |
1711 | *broadcast = \&send; |
1867 | *broadcast = \&send; |
1712 | *wait = \&_wait; |
1868 | *wait = \&recv; |
1713 | |
1869 | |
1714 | =head1 ERROR AND EXCEPTION HANDLING |
1870 | =head1 ERROR AND EXCEPTION HANDLING |
1715 | |
1871 | |
1716 | In general, AnyEvent does not do any error handling - it relies on the |
1872 | In general, AnyEvent does not do any error handling - it relies on the |
1717 | caller to do that if required. The L<AnyEvent::Strict> module (see also |
1873 | caller to do that if required. The L<AnyEvent::Strict> module (see also |
… | |
… | |
1764 | check the arguments passed to most method calls. If it finds any problems, |
1920 | check the arguments passed to most method calls. If it finds any problems, |
1765 | it will croak. |
1921 | it will croak. |
1766 | |
1922 | |
1767 | In other words, enables "strict" mode. |
1923 | In other words, enables "strict" mode. |
1768 | |
1924 | |
1769 | Unlike C<use strict> (or it's modern cousin, C<< use L<common::sense> |
1925 | Unlike C<use strict> (or its modern cousin, C<< use L<common::sense> |
1770 | >>, it is definitely recommended to keep it off in production. Keeping |
1926 | >>, it is definitely recommended to keep it off in production. Keeping |
1771 | C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs |
1927 | C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs |
1772 | can be very useful, however. |
1928 | can be very useful, however. |
1773 | |
1929 | |
1774 | =item C<PERL_ANYEVENT_MODEL> |
1930 | =item C<PERL_ANYEVENT_MODEL> |
… | |
… | |
1780 | used as event model. If it fails to load AnyEvent will proceed with |
1936 | used as event model. If it fails to load AnyEvent will proceed with |
1781 | auto detection and -probing. |
1937 | auto detection and -probing. |
1782 | |
1938 | |
1783 | This functionality might change in future versions. |
1939 | This functionality might change in future versions. |
1784 | |
1940 | |
1785 | For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you |
1941 | For example, to force the pure perl model (L<AnyEvent::Loop::Perl>) you |
1786 | could start your program like this: |
1942 | could start your program like this: |
1787 | |
1943 | |
1788 | PERL_ANYEVENT_MODEL=Perl perl ... |
1944 | PERL_ANYEVENT_MODEL=Perl perl ... |
1789 | |
1945 | |
1790 | =item C<PERL_ANYEVENT_PROTOCOLS> |
1946 | =item C<PERL_ANYEVENT_PROTOCOLS> |
… | |
… | |
1911 | warn "read: $input\n"; # output what has been read |
2067 | warn "read: $input\n"; # output what has been read |
1912 | $cv->send if $input =~ /^q/i; # quit program if /^q/i |
2068 | $cv->send if $input =~ /^q/i; # quit program if /^q/i |
1913 | }, |
2069 | }, |
1914 | ); |
2070 | ); |
1915 | |
2071 | |
1916 | my $time_watcher; # can only be used once |
|
|
1917 | |
|
|
1918 | sub new_timer { |
|
|
1919 | $timer = AnyEvent->timer (after => 1, cb => sub { |
2072 | my $time_watcher = AnyEvent->timer (after => 1, interval => 1, cb => sub { |
1920 | warn "timeout\n"; # print 'timeout' about every second |
2073 | warn "timeout\n"; # print 'timeout' at most every second |
1921 | &new_timer; # and restart the time |
|
|
1922 | }); |
2074 | }); |
1923 | } |
|
|
1924 | |
|
|
1925 | new_timer; # create first timer |
|
|
1926 | |
2075 | |
1927 | $cv->recv; # wait until user enters /^q/i |
2076 | $cv->recv; # wait until user enters /^q/i |
1928 | |
2077 | |
1929 | =head1 REAL-WORLD EXAMPLE |
2078 | =head1 REAL-WORLD EXAMPLE |
1930 | |
2079 | |
… | |
… | |
2003 | |
2152 | |
2004 | The actual code goes further and collects all errors (C<die>s, exceptions) |
2153 | The actual code goes further and collects all errors (C<die>s, exceptions) |
2005 | that occurred during request processing. The C<result> method detects |
2154 | that occurred during request processing. The C<result> method detects |
2006 | whether an exception as thrown (it is stored inside the $txn object) |
2155 | whether an exception as thrown (it is stored inside the $txn object) |
2007 | and just throws the exception, which means connection errors and other |
2156 | and just throws the exception, which means connection errors and other |
2008 | problems get reported tot he code that tries to use the result, not in a |
2157 | problems get reported to the code that tries to use the result, not in a |
2009 | random callback. |
2158 | random callback. |
2010 | |
2159 | |
2011 | All of this enables the following usage styles: |
2160 | All of this enables the following usage styles: |
2012 | |
2161 | |
2013 | 1. Blocking: |
2162 | 1. Blocking: |
… | |
… | |
2374 | As you can see, the AnyEvent + EV combination even beats the |
2523 | As you can see, the AnyEvent + EV combination even beats the |
2375 | hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl |
2524 | hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl |
2376 | backend easily beats IO::Lambda and POE. |
2525 | backend easily beats IO::Lambda and POE. |
2377 | |
2526 | |
2378 | And even the 100% non-blocking version written using the high-level (and |
2527 | And even the 100% non-blocking version written using the high-level (and |
2379 | slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda by a |
2528 | slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda |
2380 | large margin, even though it does all of DNS, tcp-connect and socket I/O |
2529 | higher level ("unoptimised") abstractions by a large margin, even though |
2381 | in a non-blocking way. |
2530 | it does all of DNS, tcp-connect and socket I/O in a non-blocking way. |
2382 | |
2531 | |
2383 | The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and |
2532 | The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and |
2384 | F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are |
2533 | F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are |
2385 | part of the IO::lambda distribution and were used without any changes. |
2534 | part of the IO::Lambda distribution and were used without any changes. |
2386 | |
2535 | |
2387 | |
2536 | |
2388 | =head1 SIGNALS |
2537 | =head1 SIGNALS |
2389 | |
2538 | |
2390 | AnyEvent currently installs handlers for these signals: |
2539 | AnyEvent currently installs handlers for these signals: |
… | |
… | |
2427 | unless defined $SIG{PIPE}; |
2576 | unless defined $SIG{PIPE}; |
2428 | |
2577 | |
2429 | =head1 RECOMMENDED/OPTIONAL MODULES |
2578 | =head1 RECOMMENDED/OPTIONAL MODULES |
2430 | |
2579 | |
2431 | One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and |
2580 | One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and |
2432 | it's built-in modules) are required to use it. |
2581 | its built-in modules) are required to use it. |
2433 | |
2582 | |
2434 | That does not mean that AnyEvent won't take advantage of some additional |
2583 | That does not mean that AnyEvent won't take advantage of some additional |
2435 | modules if they are installed. |
2584 | modules if they are installed. |
2436 | |
2585 | |
2437 | This section epxlains which additional modules will be used, and how they |
2586 | This section explains which additional modules will be used, and how they |
2438 | affect AnyEvent's operetion. |
2587 | affect AnyEvent's operation. |
2439 | |
2588 | |
2440 | =over 4 |
2589 | =over 4 |
2441 | |
2590 | |
2442 | =item L<Async::Interrupt> |
2591 | =item L<Async::Interrupt> |
2443 | |
2592 | |
… | |
… | |
2448 | catch the signals) with some delay (default is 10 seconds, look for |
2597 | catch the signals) with some delay (default is 10 seconds, look for |
2449 | C<$AnyEvent::MAX_SIGNAL_LATENCY>). |
2598 | C<$AnyEvent::MAX_SIGNAL_LATENCY>). |
2450 | |
2599 | |
2451 | If this module is available, then it will be used to implement signal |
2600 | If this module is available, then it will be used to implement signal |
2452 | catching, which means that signals will not be delayed, and the event loop |
2601 | catching, which means that signals will not be delayed, and the event loop |
2453 | will not be interrupted regularly, which is more efficient (And good for |
2602 | will not be interrupted regularly, which is more efficient (and good for |
2454 | battery life on laptops). |
2603 | battery life on laptops). |
2455 | |
2604 | |
2456 | This affects not just the pure-perl event loop, but also other event loops |
2605 | This affects not just the pure-perl event loop, but also other event loops |
2457 | that have no signal handling on their own (e.g. Glib, Tk, Qt). |
2606 | that have no signal handling on their own (e.g. Glib, Tk, Qt). |
2458 | |
2607 | |
… | |
… | |
2470 | automatic timer adjustments even when no monotonic clock is available, |
2619 | automatic timer adjustments even when no monotonic clock is available, |
2471 | can take avdantage of advanced kernel interfaces such as C<epoll> and |
2620 | can take avdantage of advanced kernel interfaces such as C<epoll> and |
2472 | C<kqueue>, and is the fastest backend I<by far>. You can even embed |
2621 | C<kqueue>, and is the fastest backend I<by far>. You can even embed |
2473 | L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>). |
2622 | L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>). |
2474 | |
2623 | |
|
|
2624 | If you only use backends that rely on another event loop (e.g. C<Tk>), |
|
|
2625 | then this module will do nothing for you. |
|
|
2626 | |
2475 | =item L<Guard> |
2627 | =item L<Guard> |
2476 | |
2628 | |
2477 | The guard module, when used, will be used to implement |
2629 | The guard module, when used, will be used to implement |
2478 | C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a |
2630 | C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a |
2479 | lot less memory), but otherwise doesn't affect guard operation much. It is |
2631 | lot less memory), but otherwise doesn't affect guard operation much. It is |
2480 | purely used for performance. |
2632 | purely used for performance. |
2481 | |
2633 | |
2482 | =item L<JSON> and L<JSON::XS> |
2634 | =item L<JSON> and L<JSON::XS> |
2483 | |
2635 | |
2484 | This module is required when you want to read or write JSON data via |
2636 | One of these modules is required when you want to read or write JSON data |
2485 | L<AnyEvent::Handle>. It is also written in pure-perl, but can take |
2637 | via L<AnyEvent::Handle>. L<JSON> is also written in pure-perl, but can take |
2486 | advantage of the ultra-high-speed L<JSON::XS> module when it is installed. |
2638 | advantage of the ultra-high-speed L<JSON::XS> module when it is installed. |
2487 | |
|
|
2488 | In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is |
|
|
2489 | installed. |
|
|
2490 | |
2639 | |
2491 | =item L<Net::SSLeay> |
2640 | =item L<Net::SSLeay> |
2492 | |
2641 | |
2493 | Implementing TLS/SSL in Perl is certainly interesting, but not very |
2642 | Implementing TLS/SSL in Perl is certainly interesting, but not very |
2494 | worthwhile: If this module is installed, then L<AnyEvent::Handle> (with |
2643 | worthwhile: If this module is installed, then L<AnyEvent::Handle> (with |
2495 | the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL. |
2644 | the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL. |
2496 | |
2645 | |
2497 | =item L<Time::HiRes> |
2646 | =item L<Time::HiRes> |
2498 | |
2647 | |
2499 | This module is part of perl since release 5.008. It will be used when the |
2648 | This module is part of perl since release 5.008. It will be used when the |
2500 | chosen event library does not come with a timing source on it's own. The |
2649 | chosen event library does not come with a timing source of its own. The |
2501 | pure-perl event loop (L<AnyEvent::Impl::Perl>) will additionally use it to |
2650 | pure-perl event loop (L<AnyEvent::Loop>) will additionally load it to |
2502 | try to use a monotonic clock for timing stability. |
2651 | try to use a monotonic clock for timing stability. |
2503 | |
2652 | |
2504 | =back |
2653 | =back |
2505 | |
2654 | |
2506 | |
2655 | |
2507 | =head1 FORK |
2656 | =head1 FORK |
2508 | |
2657 | |
2509 | Most event libraries are not fork-safe. The ones who are usually are |
2658 | Most event libraries are not fork-safe. The ones who are usually are |
2510 | because they rely on inefficient but fork-safe C<select> or C<poll> |
2659 | because they rely on inefficient but fork-safe C<select> or C<poll> calls |
2511 | calls. Only L<EV> is fully fork-aware. |
2660 | - higher performance APIs such as BSD's kqueue or the dreaded Linux epoll |
|
|
2661 | are usually badly thought-out hacks that are incompatible with fork in |
|
|
2662 | one way or another. Only L<EV> is fully fork-aware and ensures that you |
|
|
2663 | continue event-processing in both parent and child (or both, if you know |
|
|
2664 | what you are doing). |
|
|
2665 | |
|
|
2666 | This means that, in general, you cannot fork and do event processing in |
|
|
2667 | the child if the event library was initialised before the fork (which |
|
|
2668 | usually happens when the first AnyEvent watcher is created, or the library |
|
|
2669 | is loaded). |
2512 | |
2670 | |
2513 | If you have to fork, you must either do so I<before> creating your first |
2671 | If you have to fork, you must either do so I<before> creating your first |
2514 | watcher OR you must not use AnyEvent at all in the child OR you must do |
2672 | watcher OR you must not use AnyEvent at all in the child OR you must do |
2515 | something completely out of the scope of AnyEvent. |
2673 | something completely out of the scope of AnyEvent. |
|
|
2674 | |
|
|
2675 | The problem of doing event processing in the parent I<and> the child |
|
|
2676 | is much more complicated: even for backends that I<are> fork-aware or |
|
|
2677 | fork-safe, their behaviour is not usually what you want: fork clones all |
|
|
2678 | watchers, that means all timers, I/O watchers etc. are active in both |
|
|
2679 | parent and child, which is almost never what you want. USing C<exec> |
|
|
2680 | to start worker children from some kind of manage rprocess is usually |
|
|
2681 | preferred, because it is much easier and cleaner, at the expense of having |
|
|
2682 | to have another binary. |
2516 | |
2683 | |
2517 | |
2684 | |
2518 | =head1 SECURITY CONSIDERATIONS |
2685 | =head1 SECURITY CONSIDERATIONS |
2519 | |
2686 | |
2520 | AnyEvent can be forced to load any event model via |
2687 | AnyEvent can be forced to load any event model via |
… | |
… | |
2550 | pronounced). |
2717 | pronounced). |
2551 | |
2718 | |
2552 | |
2719 | |
2553 | =head1 SEE ALSO |
2720 | =head1 SEE ALSO |
2554 | |
2721 | |
|
|
2722 | Tutorial/Introduction: L<AnyEvent::Intro>. |
|
|
2723 | |
|
|
2724 | FAQ: L<AnyEvent::FAQ>. |
|
|
2725 | |
2555 | Utility functions: L<AnyEvent::Util>. |
2726 | Utility functions: L<AnyEvent::Util>. |
2556 | |
2727 | |
2557 | Event modules: L<EV>, L<EV::Glib>, L<Glib::EV>, L<Event>, L<Glib::Event>, |
2728 | Event modules: L<AnyEvent::Loop>, L<EV>, L<EV::Glib>, L<Glib::EV>, |
2558 | L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. |
2729 | L<Event>, L<Glib::Event>, L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. |
2559 | |
2730 | |
2560 | Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>, |
2731 | Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>, |
2561 | L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>, |
2732 | L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>, |
2562 | L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>, |
2733 | L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>, |
2563 | L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>. |
2734 | L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>. |
… | |
… | |
2565 | Non-blocking file handles, sockets, TCP clients and |
2736 | Non-blocking file handles, sockets, TCP clients and |
2566 | servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>. |
2737 | servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>. |
2567 | |
2738 | |
2568 | Asynchronous DNS: L<AnyEvent::DNS>. |
2739 | Asynchronous DNS: L<AnyEvent::DNS>. |
2569 | |
2740 | |
2570 | Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, |
2741 | Thread support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>. |
2571 | L<Coro::Event>, |
|
|
2572 | |
2742 | |
2573 | Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::XMPP>, |
2743 | Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::IRC>, |
2574 | L<AnyEvent::HTTP>. |
2744 | L<AnyEvent::HTTP>. |
2575 | |
2745 | |
2576 | |
2746 | |
2577 | =head1 AUTHOR |
2747 | =head1 AUTHOR |
2578 | |
2748 | |