1 | NAME |
1 | => NAME |
2 | AnyEvent - provide framework for multiple event loops |
2 | AnyEvent - provide framework for multiple event loops |
3 | |
3 | |
4 | EV, Event, Glib, Tk, Perl, Event::Lib, Qt, POE - various supported event |
4 | EV, Event, Glib, Tk, Perl, Event::Lib, Qt, POE - various supported event |
5 | loops |
5 | loops |
6 | |
6 | |
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55 | those use one of the supported event loops. It is trivial to add new |
55 | those use one of the supported event loops. It is trivial to add new |
56 | event loops to AnyEvent, too, so it is future-proof). |
56 | event loops to AnyEvent, too, so it is future-proof). |
57 | |
57 | |
58 | In addition to being free of having to use *the one and only true event |
58 | In addition to being free of having to use *the one and only true event |
59 | model*, AnyEvent also is free of bloat and policy: with POE or similar |
59 | model*, AnyEvent also is free of bloat and policy: with POE or similar |
60 | modules, you get an enourmous amount of code and strict rules you have |
60 | modules, you get an enormous amount of code and strict rules you have to |
61 | to follow. AnyEvent, on the other hand, is lean and up to the point, by |
61 | follow. AnyEvent, on the other hand, is lean and up to the point, by |
62 | only offering the functionality that is necessary, in as thin as a |
62 | only offering the functionality that is necessary, in as thin as a |
63 | wrapper as technically possible. |
63 | wrapper as technically possible. |
64 | |
64 | |
65 | Of course, if you want lots of policy (this can arguably be somewhat |
65 | Of course, if you want lots of policy (this can arguably be somewhat |
66 | useful) and you want to force your users to use the one and only event |
66 | useful) and you want to force your users to use the one and only event |
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104 | explicitly. |
104 | explicitly. |
105 | |
105 | |
106 | WATCHERS |
106 | WATCHERS |
107 | AnyEvent has the central concept of a *watcher*, which is an object that |
107 | AnyEvent has the central concept of a *watcher*, which is an object that |
108 | stores relevant data for each kind of event you are waiting for, such as |
108 | stores relevant data for each kind of event you are waiting for, such as |
109 | the callback to call, the filehandle to watch, etc. |
109 | the callback to call, the file handle to watch, etc. |
110 | |
110 | |
111 | These watchers are normal Perl objects with normal Perl lifetime. After |
111 | These watchers are normal Perl objects with normal Perl lifetime. After |
112 | creating a watcher it will immediately "watch" for events and invoke the |
112 | creating a watcher it will immediately "watch" for events and invoke the |
113 | callback when the event occurs (of course, only when the event model is |
113 | callback when the event occurs (of course, only when the event model is |
114 | in control). |
114 | in control). |
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229 | |
229 | |
230 | Although the callback might get passed parameters, their value and |
230 | Although the callback might get passed parameters, their value and |
231 | presence is undefined and you cannot rely on them. Portable AnyEvent |
231 | presence is undefined and you cannot rely on them. Portable AnyEvent |
232 | callbacks cannot use arguments passed to signal watcher callbacks. |
232 | callbacks cannot use arguments passed to signal watcher callbacks. |
233 | |
233 | |
234 | Multiple signal occurances can be clumped together into one callback |
234 | Multiple signal occurrences can be clumped together into one callback |
235 | invocation, and callback invocation will be synchronous. synchronous |
235 | invocation, and callback invocation will be synchronous. Synchronous |
236 | means that it might take a while until the signal gets handled by the |
236 | means that it might take a while until the signal gets handled by the |
237 | process, but it is guarenteed not to interrupt any other callbacks. |
237 | process, but it is guaranteed not to interrupt any other callbacks. |
238 | |
238 | |
239 | The main advantage of using these watchers is that you can share a |
239 | The main advantage of using these watchers is that you can share a |
240 | signal between multiple watchers. |
240 | signal between multiple watchers. |
241 | |
241 | |
242 | This watcher might use %SIG, so programs overwriting those signals |
242 | This watcher might use %SIG, so programs overwriting those signals |
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301 | Condition variables can be created by calling the "AnyEvent->condvar" |
301 | Condition variables can be created by calling the "AnyEvent->condvar" |
302 | method, usually without arguments. The only argument pair allowed is |
302 | method, usually without arguments. The only argument pair allowed is |
303 | "cb", which specifies a callback to be called when the condition |
303 | "cb", which specifies a callback to be called when the condition |
304 | variable becomes true. |
304 | variable becomes true. |
305 | |
305 | |
306 | After creation, the conditon variable is "false" until it becomes "true" |
306 | After creation, the condition variable is "false" until it becomes |
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307 | "true" by calling the "send" method (or calling the condition variable |
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308 | as if it were a callback, read about the caveats in the description for |
307 | by calling the "send" method. |
309 | the "->send" method). |
308 | |
310 | |
309 | Condition variables are similar to callbacks, except that you can |
311 | Condition variables are similar to callbacks, except that you can |
310 | optionally wait for them. They can also be called merge points - points |
312 | optionally wait for them. They can also be called merge points - points |
311 | in time where multiple outstandign events have been processed. And yet |
313 | in time where multiple outstanding events have been processed. And yet |
312 | another way to call them is transations - each condition variable can be |
314 | another way to call them is transactions - each condition variable can |
313 | used to represent a transaction, which finishes at some point and |
315 | be used to represent a transaction, which finishes at some point and |
314 | delivers a result. |
316 | delivers a result. |
315 | |
317 | |
316 | Condition variables are very useful to signal that something has |
318 | Condition variables are very useful to signal that something has |
317 | finished, for example, if you write a module that does asynchronous http |
319 | finished, for example, if you write a module that does asynchronous http |
318 | requests, then a condition variable would be the ideal candidate to |
320 | requests, then a condition variable would be the ideal candidate to |
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323 | you can block your main program until an event occurs - for example, you |
325 | you can block your main program until an event occurs - for example, you |
324 | could "->recv" in your main program until the user clicks the Quit |
326 | could "->recv" in your main program until the user clicks the Quit |
325 | button of your app, which would "->send" the "quit" event. |
327 | button of your app, which would "->send" the "quit" event. |
326 | |
328 | |
327 | Note that condition variables recurse into the event loop - if you have |
329 | Note that condition variables recurse into the event loop - if you have |
328 | two pieces of code that call "->recv" in a round-robbin fashion, you |
330 | two pieces of code that call "->recv" in a round-robin fashion, you |
329 | lose. Therefore, condition variables are good to export to your caller, |
331 | lose. Therefore, condition variables are good to export to your caller, |
330 | but you should avoid making a blocking wait yourself, at least in |
332 | but you should avoid making a blocking wait yourself, at least in |
331 | callbacks, as this asks for trouble. |
333 | callbacks, as this asks for trouble. |
332 | |
334 | |
333 | Condition variables are represented by hash refs in perl, and the keys |
335 | Condition variables are represented by hash refs in perl, and the keys |
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338 | |
340 | |
339 | There are two "sides" to a condition variable - the "producer side" |
341 | There are two "sides" to a condition variable - the "producer side" |
340 | which eventually calls "-> send", and the "consumer side", which waits |
342 | which eventually calls "-> send", and the "consumer side", which waits |
341 | for the send to occur. |
343 | for the send to occur. |
342 | |
344 | |
343 | Example: |
345 | Example: wait for a timer. |
344 | |
346 | |
345 | # wait till the result is ready |
347 | # wait till the result is ready |
346 | my $result_ready = AnyEvent->condvar; |
348 | my $result_ready = AnyEvent->condvar; |
347 | |
349 | |
348 | # do something such as adding a timer |
350 | # do something such as adding a timer |
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356 | |
358 | |
357 | # this "blocks" (while handling events) till the callback |
359 | # this "blocks" (while handling events) till the callback |
358 | # calls send |
360 | # calls send |
359 | $result_ready->recv; |
361 | $result_ready->recv; |
360 | |
362 | |
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363 | Example: wait for a timer, but take advantage of the fact that condition |
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364 | variables are also code references. |
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365 | |
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366 | my $done = AnyEvent->condvar; |
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367 | my $delay = AnyEvent->timer (after => 5, cb => $done); |
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368 | $done->recv; |
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369 | |
361 | METHODS FOR PRODUCERS |
370 | METHODS FOR PRODUCERS |
362 | These methods should only be used by the producing side, i.e. the |
371 | These methods should only be used by the producing side, i.e. the |
363 | code/module that eventually sends the signal. Note that it is also the |
372 | code/module that eventually sends the signal. Note that it is also the |
364 | producer side which creates the condvar in most cases, but it isn't |
373 | producer side which creates the condvar in most cases, but it isn't |
365 | uncommon for the consumer to create it as well. |
374 | uncommon for the consumer to create it as well. |
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372 | If a callback has been set on the condition variable, it is called |
381 | If a callback has been set on the condition variable, it is called |
373 | immediately from within send. |
382 | immediately from within send. |
374 | |
383 | |
375 | Any arguments passed to the "send" call will be returned by all |
384 | Any arguments passed to the "send" call will be returned by all |
376 | future "->recv" calls. |
385 | future "->recv" calls. |
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386 | |
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387 | Condition variables are overloaded so one can call them directly (as |
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388 | a code reference). Calling them directly is the same as calling |
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389 | "send". Note, however, that many C-based event loops do not handle |
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390 | overloading, so as tempting as it may be, passing a condition |
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391 | variable instead of a callback does not work. Both the pure perl and |
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392 | EV loops support overloading, however, as well as all functions that |
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393 | use perl to invoke a callback (as in AnyEvent::Socket and |
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394 | AnyEvent::DNS for example). |
377 | |
395 | |
378 | $cv->croak ($error) |
396 | $cv->croak ($error) |
379 | Similar to send, but causes all call's to "->recv" to invoke |
397 | Similar to send, but causes all call's to "->recv" to invoke |
380 | "Carp::croak" with the given error message/object/scalar. |
398 | "Carp::croak" with the given error message/object/scalar. |
381 | |
399 | |
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427 | (the loop doesn't execute once). |
445 | (the loop doesn't execute once). |
428 | |
446 | |
429 | This is the general pattern when you "fan out" into multiple |
447 | This is the general pattern when you "fan out" into multiple |
430 | subrequests: use an outer "begin"/"end" pair to set the callback and |
448 | subrequests: use an outer "begin"/"end" pair to set the callback and |
431 | ensure "end" is called at least once, and then, for each subrequest |
449 | ensure "end" is called at least once, and then, for each subrequest |
432 | you start, call "begin" and for eahc subrequest you finish, call |
450 | you start, call "begin" and for each subrequest you finish, call |
433 | "end". |
451 | "end". |
434 | |
452 | |
435 | METHODS FOR CONSUMERS |
453 | METHODS FOR CONSUMERS |
436 | These methods should only be used by the consuming side, i.e. the code |
454 | These methods should only be used by the consuming side, i.e. the code |
437 | awaits the condition. |
455 | awaits the condition. |
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453 | (programs might want to do that to stay interactive), so *if you are |
471 | (programs might want to do that to stay interactive), so *if you are |
454 | using this from a module, never require a blocking wait*, but let |
472 | using this from a module, never require a blocking wait*, but let |
455 | the caller decide whether the call will block or not (for example, |
473 | the caller decide whether the call will block or not (for example, |
456 | by coupling condition variables with some kind of request results |
474 | by coupling condition variables with some kind of request results |
457 | and supporting callbacks so the caller knows that getting the result |
475 | and supporting callbacks so the caller knows that getting the result |
458 | will not block, while still suppporting blocking waits if the caller |
476 | will not block, while still supporting blocking waits if the caller |
459 | so desires). |
477 | so desires). |
460 | |
478 | |
461 | Another reason *never* to "->recv" in a module is that you cannot |
479 | Another reason *never* to "->recv" in a module is that you cannot |
462 | sensibly have two "->recv"'s in parallel, as that would require |
480 | sensibly have two "->recv"'s in parallel, as that would require |
463 | multiple interpreters or coroutines/threads, none of which |
481 | multiple interpreters or coroutines/threads, none of which |
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566 | If it doesn't care, it can just "use AnyEvent" and use it itself, or not |
584 | If it doesn't care, it can just "use AnyEvent" and use it itself, or not |
567 | do anything special (it does not need to be event-based) and let |
585 | do anything special (it does not need to be event-based) and let |
568 | AnyEvent decide which implementation to chose if some module relies on |
586 | AnyEvent decide which implementation to chose if some module relies on |
569 | it. |
587 | it. |
570 | |
588 | |
571 | If the main program relies on a specific event model. For example, in |
589 | If the main program relies on a specific event model - for example, in |
572 | Gtk2 programs you have to rely on the Glib module. You should load the |
590 | Gtk2 programs you have to rely on the Glib module - you should load the |
573 | event module before loading AnyEvent or any module that uses it: |
591 | event module before loading AnyEvent or any module that uses it: |
574 | generally speaking, you should load it as early as possible. The reason |
592 | generally speaking, you should load it as early as possible. The reason |
575 | is that modules might create watchers when they are loaded, and AnyEvent |
593 | is that modules might create watchers when they are loaded, and AnyEvent |
576 | will decide on the event model to use as soon as it creates watchers, |
594 | will decide on the event model to use as soon as it creates watchers, |
577 | and it might chose the wrong one unless you load the correct one |
595 | and it might chose the wrong one unless you load the correct one |
578 | yourself. |
596 | yourself. |
579 | |
597 | |
580 | You can chose to use a rather inefficient pure-perl implementation by |
598 | You can chose to use a pure-perl implementation by loading the |
581 | loading the "AnyEvent::Impl::Perl" module, which gives you similar |
599 | "AnyEvent::Impl::Perl" module, which gives you similar behaviour |
582 | behaviour everywhere, but letting AnyEvent chose is generally better. |
600 | everywhere, but letting AnyEvent chose the model is generally better. |
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601 | |
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602 | MAINLOOP EMULATION |
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603 | Sometimes (often for short test scripts, or even standalone programs who |
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604 | only want to use AnyEvent), you do not want to run a specific event |
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605 | loop. |
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606 | |
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607 | In that case, you can use a condition variable like this: |
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608 | |
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609 | AnyEvent->condvar->recv; |
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610 | |
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611 | This has the effect of entering the event loop and looping forever. |
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612 | |
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613 | Note that usually your program has some exit condition, in which case it |
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614 | is better to use the "traditional" approach of storing a condition |
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615 | variable somewhere, waiting for it, and sending it when the program |
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616 | should exit cleanly. |
583 | |
617 | |
584 | OTHER MODULES |
618 | OTHER MODULES |
585 | The following is a non-exhaustive list of additional modules that use |
619 | The following is a non-exhaustive list of additional modules that use |
586 | AnyEvent and can therefore be mixed easily with other AnyEvent modules |
620 | AnyEvent and can therefore be mixed easily with other AnyEvent modules |
587 | in the same program. Some of the modules come with AnyEvent, some are |
621 | in the same program. Some of the modules come with AnyEvent, some are |
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594 | |
628 | |
595 | AnyEvent::Handle |
629 | AnyEvent::Handle |
596 | Provide read and write buffers and manages watchers for reads and |
630 | Provide read and write buffers and manages watchers for reads and |
597 | writes. |
631 | writes. |
598 | |
632 | |
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633 | AnyEvent::Socket |
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634 | Provides various utility functions for (internet protocol) sockets, |
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635 | addresses and name resolution. Also functions to create non-blocking |
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636 | tcp connections or tcp servers, with IPv6 and SRV record support and |
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637 | more. |
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638 | |
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639 | AnyEvent::DNS |
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640 | Provides rich asynchronous DNS resolver capabilities. |
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641 | |
599 | AnyEvent::HTTPD |
642 | AnyEvent::HTTPD |
600 | Provides a simple web application server framework. |
643 | Provides a simple web application server framework. |
601 | |
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602 | AnyEvent::DNS |
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603 | Provides asynchronous DNS resolver capabilities, beyond what |
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604 | AnyEvent::Util offers. |
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605 | |
644 | |
606 | AnyEvent::FastPing |
645 | AnyEvent::FastPing |
607 | The fastest ping in the west. |
646 | The fastest ping in the west. |
608 | |
647 | |
609 | Net::IRC3 |
648 | Net::IRC3 |
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693 | When set to 2 or higher, cause AnyEvent to report to STDERR which |
732 | When set to 2 or higher, cause AnyEvent to report to STDERR which |
694 | event model it chooses. |
733 | event model it chooses. |
695 | |
734 | |
696 | "PERL_ANYEVENT_MODEL" |
735 | "PERL_ANYEVENT_MODEL" |
697 | This can be used to specify the event model to be used by AnyEvent, |
736 | This can be used to specify the event model to be used by AnyEvent, |
698 | before autodetection and -probing kicks in. It must be a string |
737 | before auto detection and -probing kicks in. It must be a string |
699 | consisting entirely of ASCII letters. The string "AnyEvent::Impl::" |
738 | consisting entirely of ASCII letters. The string "AnyEvent::Impl::" |
700 | gets prepended and the resulting module name is loaded and if the |
739 | gets prepended and the resulting module name is loaded and if the |
701 | load was successful, used as event model. If it fails to load |
740 | load was successful, used as event model. If it fails to load |
702 | AnyEvent will proceed with autodetection and -probing. |
741 | AnyEvent will proceed with auto detection and -probing. |
703 | |
742 | |
704 | This functionality might change in future versions. |
743 | This functionality might change in future versions. |
705 | |
744 | |
706 | For example, to force the pure perl model (AnyEvent::Impl::Perl) you |
745 | For example, to force the pure perl model (AnyEvent::Impl::Perl) you |
707 | could start your program like this: |
746 | could start your program like this: |
708 | |
747 | |
709 | PERL_ANYEVENT_MODEL=Perl perl ... |
748 | PERL_ANYEVENT_MODEL=Perl perl ... |
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749 | |
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750 | "PERL_ANYEVENT_PROTOCOLS" |
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751 | Used by both AnyEvent::DNS and AnyEvent::Socket to determine |
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752 | preferences for IPv4 or IPv6. The default is unspecified (and might |
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753 | change, or be the result of auto probing). |
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754 | |
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755 | Must be set to a comma-separated list of protocols or address |
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756 | families, current supported: "ipv4" and "ipv6". Only protocols |
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757 | mentioned will be used, and preference will be given to protocols |
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758 | mentioned earlier in the list. |
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759 | |
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760 | This variable can effectively be used for denial-of-service attacks |
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761 | against local programs (e.g. when setuid), although the impact is |
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762 | likely small, as the program has to handle connection errors |
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763 | already- |
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764 | |
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765 | Examples: "PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6" - prefer IPv4 over |
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766 | IPv6, but support both and try to use both. |
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767 | "PERL_ANYEVENT_PROTOCOLS=ipv4" - only support IPv4, never try to |
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768 | resolve or contact IPv6 addresses. |
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769 | "PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4" support either IPv4 or IPv6, but |
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770 | prefer IPv6 over IPv4. |
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771 | |
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772 | "PERL_ANYEVENT_EDNS0" |
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773 | Used by AnyEvent::DNS to decide whether to use the EDNS0 extension |
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774 | for DNS. This extension is generally useful to reduce DNS traffic, |
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775 | but some (broken) firewalls drop such DNS packets, which is why it |
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776 | is off by default. |
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777 | |
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778 | Setting this variable to 1 will cause AnyEvent::DNS to announce |
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779 | EDNS0 in its DNS requests. |
710 | |
780 | |
711 | EXAMPLE PROGRAM |
781 | EXAMPLE PROGRAM |
712 | The following program uses an I/O watcher to read data from STDIN, a |
782 | The following program uses an I/O watcher to read data from STDIN, a |
713 | timer to display a message once per second, and a condition variable to |
783 | timer to display a message once per second, and a condition variable to |
714 | quit the program when the user enters quit: |
784 | quit the program when the user enters quit: |
… | |
… | |
796 | syswrite $txn->{fh}, $txn->{request} |
866 | syswrite $txn->{fh}, $txn->{request} |
797 | or die "connection or write error"; |
867 | or die "connection or write error"; |
798 | $txn->{w} = AnyEvent->io (fh => $txn->{fh}, poll => 'r', cb => sub { $txn->fh_ready_r }); |
868 | $txn->{w} = AnyEvent->io (fh => $txn->{fh}, poll => 'r', cb => sub { $txn->fh_ready_r }); |
799 | |
869 | |
800 | Again, "fh_ready_r" waits till all data has arrived, and then stores the |
870 | Again, "fh_ready_r" waits till all data has arrived, and then stores the |
801 | result and signals any possible waiters that the request ahs finished: |
871 | result and signals any possible waiters that the request has finished: |
802 | |
872 | |
803 | sysread $txn->{fh}, $txn->{buf}, length $txn->{$buf}; |
873 | sysread $txn->{fh}, $txn->{buf}, length $txn->{$buf}; |
804 | |
874 | |
805 | if (end-of-file or data complete) { |
875 | if (end-of-file or data complete) { |
806 | $txn->{result} = $txn->{buf}; |
876 | $txn->{result} = $txn->{buf}; |
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814 | |
884 | |
815 | $txn->{finished}->recv; |
885 | $txn->{finished}->recv; |
816 | return $txn->{result}; |
886 | return $txn->{result}; |
817 | |
887 | |
818 | The actual code goes further and collects all errors ("die"s, |
888 | The actual code goes further and collects all errors ("die"s, |
819 | exceptions) that occured during request processing. The "result" method |
889 | exceptions) that occurred during request processing. The "result" method |
820 | detects whether an exception as thrown (it is stored inside the $txn |
890 | detects whether an exception as thrown (it is stored inside the $txn |
821 | object) and just throws the exception, which means connection errors and |
891 | object) and just throws the exception, which means connection errors and |
822 | other problems get reported tot he code that tries to use the result, |
892 | other problems get reported tot he code that tries to use the result, |
823 | not in a random callback. |
893 | not in a random callback. |
824 | |
894 | |
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867 | over the event loops themselves and to give you an impression of the |
937 | over the event loops themselves and to give you an impression of the |
868 | speed of various event loops I prepared some benchmarks. |
938 | speed of various event loops I prepared some benchmarks. |
869 | |
939 | |
870 | BENCHMARKING ANYEVENT OVERHEAD |
940 | BENCHMARKING ANYEVENT OVERHEAD |
871 | Here is a benchmark of various supported event models used natively and |
941 | Here is a benchmark of various supported event models used natively and |
872 | through anyevent. The benchmark creates a lot of timers (with a zero |
942 | through AnyEvent. The benchmark creates a lot of timers (with a zero |
873 | timeout) and I/O watchers (watching STDOUT, a pty, to become writable, |
943 | timeout) and I/O watchers (watching STDOUT, a pty, to become writable, |
874 | which it is), lets them fire exactly once and destroys them again. |
944 | which it is), lets them fire exactly once and destroys them again. |
875 | |
945 | |
876 | Source code for this benchmark is found as eg/bench in the AnyEvent |
946 | Source code for this benchmark is found as eg/bench in the AnyEvent |
877 | distribution. |
947 | distribution. |
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992 | |
1062 | |
993 | * You should avoid POE like the plague if you want performance or |
1063 | * You should avoid POE like the plague if you want performance or |
994 | reasonable memory usage. |
1064 | reasonable memory usage. |
995 | |
1065 | |
996 | BENCHMARKING THE LARGE SERVER CASE |
1066 | BENCHMARKING THE LARGE SERVER CASE |
997 | This benchmark atcually benchmarks the event loop itself. It works by |
1067 | This benchmark actually benchmarks the event loop itself. It works by |
998 | creating a number of "servers": each server consists of a socketpair, a |
1068 | creating a number of "servers": each server consists of a socket pair, a |
999 | timeout watcher that gets reset on activity (but never fires), and an |
1069 | timeout watcher that gets reset on activity (but never fires), and an |
1000 | I/O watcher waiting for input on one side of the socket. Each time the |
1070 | I/O watcher waiting for input on one side of the socket. Each time the |
1001 | socket watcher reads a byte it will write that byte to a random other |
1071 | socket watcher reads a byte it will write that byte to a random other |
1002 | "server". |
1072 | "server". |
1003 | |
1073 | |
1004 | The effect is that there will be a lot of I/O watchers, only part of |
1074 | The effect is that there will be a lot of I/O watchers, only part of |
1005 | which are active at any one point (so there is a constant number of |
1075 | which are active at any one point (so there is a constant number of |
1006 | active fds for each loop iterstaion, but which fds these are is random). |
1076 | active fds for each loop iteration, but which fds these are is random). |
1007 | The timeout is reset each time something is read because that reflects |
1077 | The timeout is reset each time something is read because that reflects |
1008 | how most timeouts work (and puts extra pressure on the event loops). |
1078 | how most timeouts work (and puts extra pressure on the event loops). |
1009 | |
1079 | |
1010 | In this benchmark, we use 10000 socketpairs (20000 sockets), of which |
1080 | In this benchmark, we use 10000 socket pairs (20000 sockets), of which |
1011 | 100 (1%) are active. This mirrors the activity of large servers with |
1081 | 100 (1%) are active. This mirrors the activity of large servers with |
1012 | many connections, most of which are idle at any one point in time. |
1082 | many connections, most of which are idle at any one point in time. |
1013 | |
1083 | |
1014 | Source code for this benchmark is found as eg/bench2 in the AnyEvent |
1084 | Source code for this benchmark is found as eg/bench2 in the AnyEvent |
1015 | distribution. |
1085 | distribution. |
1016 | |
1086 | |
1017 | Explanation of the columns |
1087 | Explanation of the columns |
1018 | *sockets* is the number of sockets, and twice the number of "servers" |
1088 | *sockets* is the number of sockets, and twice the number of "servers" |
1019 | (as each server has a read and write socket end). |
1089 | (as each server has a read and write socket end). |
1020 | |
1090 | |
1021 | *create* is the time it takes to create a socketpair (which is |
1091 | *create* is the time it takes to create a socket pair (which is |
1022 | nontrivial) and two watchers: an I/O watcher and a timeout watcher. |
1092 | nontrivial) and two watchers: an I/O watcher and a timeout watcher. |
1023 | |
1093 | |
1024 | *request*, the most important value, is the time it takes to handle a |
1094 | *request*, the most important value, is the time it takes to handle a |
1025 | single "request", that is, reading the token from the pipe and |
1095 | single "request", that is, reading the token from the pipe and |
1026 | forwarding it to another server. This includes deleting the old timeout |
1096 | forwarding it to another server. This includes deleting the old timeout |
… | |
… | |
1090 | and speed most when you have lots of watchers, not when you only have a |
1160 | and speed most when you have lots of watchers, not when you only have a |
1091 | few of them). |
1161 | few of them). |
1092 | |
1162 | |
1093 | EV is again fastest. |
1163 | EV is again fastest. |
1094 | |
1164 | |
1095 | Perl again comes second. It is noticably faster than the C-based event |
1165 | Perl again comes second. It is noticeably faster than the C-based event |
1096 | loops Event and Glib, although the difference is too small to really |
1166 | loops Event and Glib, although the difference is too small to really |
1097 | matter. |
1167 | matter. |
1098 | |
1168 | |
1099 | POE also performs much better in this case, but is is still far behind |
1169 | POE also performs much better in this case, but is is still far behind |
1100 | the others. |
1170 | the others. |
… | |
… | |
1129 | Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can |
1199 | Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can |
1130 | be used to probe what backend is used and gain other information (which |
1200 | be used to probe what backend is used and gain other information (which |
1131 | is probably even less useful to an attacker than PERL_ANYEVENT_MODEL). |
1201 | is probably even less useful to an attacker than PERL_ANYEVENT_MODEL). |
1132 | |
1202 | |
1133 | SEE ALSO |
1203 | SEE ALSO |
|
|
1204 | Utility functions: AnyEvent::Util. |
|
|
1205 | |
1134 | Event modules: EV, EV::Glib, Glib::EV, Event, Glib::Event, Glib, Tk, |
1206 | Event modules: EV, EV::Glib, Glib::EV, Event, Glib::Event, Glib, Tk, |
1135 | Event::Lib, Qt, POE. |
1207 | Event::Lib, Qt, POE. |
1136 | |
1208 | |
1137 | Implementations: AnyEvent::Impl::EV, AnyEvent::Impl::Event, |
1209 | Implementations: AnyEvent::Impl::EV, AnyEvent::Impl::Event, |
1138 | AnyEvent::Impl::Glib, AnyEvent::Impl::Tk, AnyEvent::Impl::Perl, |
1210 | AnyEvent::Impl::Glib, AnyEvent::Impl::Tk, AnyEvent::Impl::Perl, |
1139 | AnyEvent::Impl::EventLib, AnyEvent::Impl::Qt, AnyEvent::Impl::POE. |
1211 | AnyEvent::Impl::EventLib, AnyEvent::Impl::Qt, AnyEvent::Impl::POE. |
1140 | |
1212 | |
|
|
1213 | Non-blocking file handles, sockets, TCP clients and servers: |
|
|
1214 | AnyEvent::Handle, AnyEvent::Socket. |
|
|
1215 | |
|
|
1216 | Asynchronous DNS: AnyEvent::DNS. |
|
|
1217 | |
1141 | Coroutine support: Coro, Coro::AnyEvent, Coro::EV, Coro::Event, |
1218 | Coroutine support: Coro, Coro::AnyEvent, Coro::EV, Coro::Event, |
1142 | |
1219 | |
1143 | Nontrivial usage examples: Net::FCP, Net::XMPP2. |
1220 | Nontrivial usage examples: Net::FCP, Net::XMPP2, AnyEvent::DNS. |
1144 | |
1221 | |
1145 | AUTHOR |
1222 | AUTHOR |
1146 | Marc Lehmann <schmorp@schmorp.de> |
1223 | Marc Lehmann <schmorp@schmorp.de> |
1147 | http://home.schmorp.de/ |
1224 | http://home.schmorp.de/ |
1148 | |
1225 | |