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46 | my ($w, $revents) = @_; |
46 | my ($w, $revents) = @_; |
47 | warn $w->path, " has changed somehow.\n"; |
47 | warn $w->path, " has changed somehow.\n"; |
48 | }; |
48 | }; |
49 | |
49 | |
50 | # MAINLOOP |
50 | # MAINLOOP |
51 | EV::run; # loop until EV::unloop is called or all watchers stop |
51 | EV::run; # loop until EV::break is called or all watchers stop |
52 | EV::run EV::RUN_ONCE; # block until at least one event could be handled |
52 | EV::run EV::RUN_ONCE; # block until at least one event could be handled |
53 | EV::run EV::RUN_NOWAIT; # try to handle same events, but do not block |
53 | EV::run EV::RUN_NOWAIT; # try to handle same events, but do not block |
54 | |
54 | |
55 | BEFORE YOU START USING THIS MODULE |
55 | BEFORE YOU START USING THIS MODULE |
56 | If you only need timer, I/O, signal, child and idle watchers and not the |
56 | If you only need timer, I/O, signal, child and idle watchers and not the |
… | |
… | |
195 | |
195 | |
196 | EV::now_update |
196 | EV::now_update |
197 | $loop->now_update |
197 | $loop->now_update |
198 | Establishes the current time by querying the kernel, updating the |
198 | Establishes the current time by querying the kernel, updating the |
199 | time returned by "EV::now" in the progress. This is a costly |
199 | time returned by "EV::now" in the progress. This is a costly |
200 | operation and is usually done automatically within "EV::loop". |
200 | operation and is usually done automatically within "EV::run". |
201 | |
201 | |
202 | This function is rarely useful, but when some event callback runs |
202 | This function is rarely useful, but when some event callback runs |
203 | for a very long time without entering the event loop, updating |
203 | for a very long time without entering the event loop, updating |
204 | libev's idea of the current time is a good idea. |
204 | libev's idea of the current time is a good idea. |
205 | |
205 | |
… | |
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233 | $backend = EV::backend |
233 | $backend = EV::backend |
234 | $backend = $loop->backend |
234 | $backend = $loop->backend |
235 | Returns an integer describing the backend used by libev |
235 | Returns an integer describing the backend used by libev |
236 | (EV::BACKEND_SELECT or EV::BACKEND_EPOLL). |
236 | (EV::BACKEND_SELECT or EV::BACKEND_EPOLL). |
237 | |
237 | |
238 | EV::run [$flags] |
238 | $active = EV::run [$flags] |
239 | $loop->run ([$flags]) |
239 | $active = $loop->run ([$flags]) |
240 | Begin checking for events and calling callbacks. It returns when a |
240 | Begin checking for events and calling callbacks. It returns when a |
241 | callback calls EV::unloop. |
241 | callback calls EV::break or the flags are nonzero (in which case the |
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242 | return value is true) or when there are no active watchers which |
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243 | reference the loop (keepalive is true), in which case the return |
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244 | value will be false. The return value can generally be interpreted |
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245 | as "if true, there is more work left to do". |
242 | |
246 | |
243 | The $flags argument can be one of the following: |
247 | The $flags argument can be one of the following: |
244 | |
248 | |
245 | 0 as above |
249 | 0 as above |
246 | EV::RUN_ONCE block at most once (wait, but do not loop) |
250 | EV::RUN_ONCE block at most once (wait, but do not loop) |
247 | EV::RUN_NOWAIT do not block at all (fetch/handle events but do not wait) |
251 | EV::RUN_NOWAIT do not block at all (fetch/handle events but do not wait) |
248 | |
252 | |
249 | EV::break [$how] |
253 | EV::break [$how] |
250 | $loop->break ([$how]) |
254 | $loop->break ([$how]) |
251 | When called with no arguments or an argument of EV::BREAK_ONE, makes |
255 | When called with no arguments or an argument of EV::BREAK_ONE, makes |
252 | the innermost call to EV::loop return. |
256 | the innermost call to EV::run return. |
253 | |
257 | |
254 | When called with an argument of EV::BREAK_ALL, all calls to EV::loop |
258 | When called with an argument of EV::BREAK_ALL, all calls to EV::run |
255 | will return as fast as possible. |
259 | will return as fast as possible. |
256 | |
260 | |
257 | When called with an argument of EV::BREAK_CANCEL, any pending break |
261 | When called with an argument of EV::BREAK_CANCEL, any pending break |
258 | will be cancelled. |
262 | will be cancelled. |
259 | |
263 | |
… | |
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272 | "EV::READ | EV::WRITE", indicating the type of I/O event you want to |
276 | "EV::READ | EV::WRITE", indicating the type of I/O event you want to |
273 | wait for. If you do not want to wait for some I/O event, specify |
277 | wait for. If you do not want to wait for some I/O event, specify |
274 | "undef" for $fh_or_undef and 0 for $events). |
278 | "undef" for $fh_or_undef and 0 for $events). |
275 | |
279 | |
276 | If timeout is "undef" or negative, then there will be no timeout. |
280 | If timeout is "undef" or negative, then there will be no timeout. |
277 | Otherwise a EV::timer with this value will be started. |
281 | Otherwise an "EV::timer" with this value will be started. |
278 | |
282 | |
279 | When an error occurs or either the timeout or I/O watcher triggers, |
283 | When an error occurs or either the timeout or I/O watcher triggers, |
280 | then the callback will be called with the received event set (in |
284 | then the callback will be called with the received event set (in |
281 | general you can expect it to be a combination of "EV::ERROR", |
285 | general you can expect it to be a combination of "EV::ERROR", |
282 | "EV::READ", "EV::WRITE" and "EV::TIMER"). |
286 | "EV::READ", "EV::WRITE" and "EV::TIMER"). |
… | |
… | |
297 | call as if the signal specified by $signal had occured. |
301 | call as if the signal specified by $signal had occured. |
298 | |
302 | |
299 | EV::feed_signal $signal |
303 | EV::feed_signal $signal |
300 | Feed a signal event into EV - unlike "EV::feed_signal_event", this |
304 | Feed a signal event into EV - unlike "EV::feed_signal_event", this |
301 | works regardless of which loop has registered the signal, and is |
305 | works regardless of which loop has registered the signal, and is |
302 | mainly useful fro custom signal implementations. |
306 | mainly useful for custom signal implementations. |
303 | |
307 | |
304 | EV::set_io_collect_interval $time |
308 | EV::set_io_collect_interval $time |
305 | $loop->set_io_collect_interval ($time) |
309 | $loop->set_io_collect_interval ($time) |
306 | EV::set_timeout_collect_interval $time |
310 | EV::set_timeout_collect_interval $time |
307 | $loop->set_timeout_collect_interval ($time) |
311 | $loop->set_timeout_collect_interval ($time) |
… | |
… | |
410 | If the watcher is pending, this function clears its pending status |
414 | If the watcher is pending, this function clears its pending status |
411 | and returns its $revents bitset (as if its callback was invoked). If |
415 | and returns its $revents bitset (as if its callback was invoked). If |
412 | the watcher isn't pending it does nothing and returns 0. |
416 | the watcher isn't pending it does nothing and returns 0. |
413 | |
417 | |
414 | $previous_state = $w->keepalive ($bool) |
418 | $previous_state = $w->keepalive ($bool) |
415 | Normally, "EV::loop" will return when there are no active watchers |
419 | Normally, "EV::run" will return when there are no active watchers |
416 | (which is a "deadlock" because no progress can be made anymore). |
420 | (which is a "deadlock" because no progress can be made anymore). |
417 | This is convenient because it allows you to start your watchers (and |
421 | This is convenient because it allows you to start your watchers (and |
418 | your jobs), call "EV::loop" once and when it returns you know that |
422 | your jobs), call "EV::run" once and when it returns you know that |
419 | all your jobs are finished (or they forgot to register some watchers |
423 | all your jobs are finished (or they forgot to register some watchers |
420 | for their task :). |
424 | for their task :). |
421 | |
425 | |
422 | Sometimes, however, this gets in your way, for example when the |
426 | Sometimes, however, this gets in your way, for example when the |
423 | module that calls "EV::loop" (usually the main program) is not the |
427 | module that calls "EV::run" (usually the main program) is not the |
424 | same module as a long-living watcher (for example a DNS client |
428 | same module as a long-living watcher (for example a DNS client |
425 | module written by somebody else even). Then you might want any |
429 | module written by somebody else even). Then you might want any |
426 | outstanding requests to be handled, but you would not want to keep |
430 | outstanding requests to be handled, but you would not want to keep |
427 | "EV::loop" from returning just because you happen to have this |
431 | "EV::run" from returning just because you happen to have this |
428 | long-running UDP port watcher. |
432 | long-running UDP port watcher. |
429 | |
433 | |
430 | In this case you can clear the keepalive status, which means that |
434 | In this case you can clear the keepalive status, which means that |
431 | even though your watcher is active, it won't keep "EV::loop" from |
435 | even though your watcher is active, it won't keep "EV::run" from |
432 | returning. |
436 | returning. |
433 | |
437 | |
434 | The initial value for keepalive is true (enabled), and you can |
438 | The initial value for keepalive is true (enabled), and you can |
435 | change it any time. |
439 | change it any time. |
436 | |
440 | |
… | |
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478 | TIMER WATCHERS - relative and optionally repeating timeouts |
482 | TIMER WATCHERS - relative and optionally repeating timeouts |
479 | $w = EV::timer $after, $repeat, $callback |
483 | $w = EV::timer $after, $repeat, $callback |
480 | $w = EV::timer_ns $after, $repeat, $callback |
484 | $w = EV::timer_ns $after, $repeat, $callback |
481 | $w = $loop->timer ($after, $repeat, $callback) |
485 | $w = $loop->timer ($after, $repeat, $callback) |
482 | $w = $loop->timer_ns ($after, $repeat, $callback) |
486 | $w = $loop->timer_ns ($after, $repeat, $callback) |
483 | Calls the callback after $after seconds (which may be fractional). |
487 | Calls the callback after $after seconds (which may be fractional or |
484 | If $repeat is non-zero, the timer will be restarted (with the |
488 | negative). If $repeat is non-zero, the timer will be restarted (with |
485 | $repeat value as $after) after the callback returns. |
489 | the $repeat value as $after) after the callback returns. |
486 | |
490 | |
487 | This means that the callback would be called roughly after $after |
491 | This means that the callback would be called roughly after $after |
488 | seconds, and then every $repeat seconds. The timer does his best not |
492 | seconds, and then every $repeat seconds. The timer does his best not |
489 | to drift, but it will not invoke the timer more often then once per |
493 | to drift, but it will not invoke the timer more often then once per |
490 | event loop iteration, and might drift in other cases. If that isn't |
494 | event loop iteration, and might drift in other cases. If that isn't |
… | |
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497 | the same time. |
501 | the same time. |
498 | |
502 | |
499 | The "timer_ns" variant doesn't start (activate) the newly created |
503 | The "timer_ns" variant doesn't start (activate) the newly created |
500 | watcher. |
504 | watcher. |
501 | |
505 | |
502 | $w->set ($after, $repeat) |
506 | $w->set ($after, $repeat = 0) |
503 | Reconfigures the watcher, see the constructor above for details. Can |
507 | Reconfigures the watcher, see the constructor above for details. Can |
504 | be called at any time. |
508 | be called at any time. |
505 | |
509 | |
506 | $w->again |
510 | $w->again |
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|
511 | $w->again ($repeat) |
507 | Similar to the "start" method, but has special semantics for |
512 | Similar to the "start" method, but has special semantics for |
508 | repeating timers: |
513 | repeating timers: |
509 | |
514 | |
510 | If the timer is active and non-repeating, it will be stopped. |
515 | If the timer is active and non-repeating, it will be stopped. |
511 | |
516 | |
… | |
… | |
519 | |
524 | |
520 | This behaviour is useful when you have a timeout for some IO |
525 | This behaviour is useful when you have a timeout for some IO |
521 | operation. You create a timer object with the same value for $after |
526 | operation. You create a timer object with the same value for $after |
522 | and $repeat, and then, in the read/write watcher, run the "again" |
527 | and $repeat, and then, in the read/write watcher, run the "again" |
523 | method on the timeout. |
528 | method on the timeout. |
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|
529 | |
|
|
530 | If called with a $repeat argument, then it uses this a timer repeat |
|
|
531 | value. |
|
|
532 | |
|
|
533 | $after = $w->remaining |
|
|
534 | Calculates and returns the remaining time till the timer will fire. |
524 | |
535 | |
525 | PERIODIC WATCHERS - to cron or not to cron? |
536 | PERIODIC WATCHERS - to cron or not to cron? |
526 | $w = EV::periodic $at, $interval, $reschedule_cb, $callback |
537 | $w = EV::periodic $at, $interval, $reschedule_cb, $callback |
527 | $w = EV::periodic_ns $at, $interval, $reschedule_cb, $callback |
538 | $w = EV::periodic_ns $at, $interval, $reschedule_cb, $callback |
528 | $w = $loop->periodic ($at, $interval, $reschedule_cb, $callback) |
539 | $w = $loop->periodic ($at, $interval, $reschedule_cb, $callback) |
… | |
… | |
545 | system time reaches or surpasses this time. |
556 | system time reaches or surpasses this time. |
546 | |
557 | |
547 | * repeating interval timer ($interval > 0, $reschedule_cb = 0) |
558 | * repeating interval timer ($interval > 0, $reschedule_cb = 0) |
548 | |
559 | |
549 | In this mode the watcher will always be scheduled to time out at |
560 | In this mode the watcher will always be scheduled to time out at |
550 | the next "$at + N * $interval" time (for some integer N) and |
561 | the next "$at + N * $interval" time (for the lowest integer N) |
551 | then repeat, regardless of any time jumps. |
562 | and then repeat, regardless of any time jumps. Note that, since |
|
|
563 | "N" can be negative, the first trigger can happen before $at. |
552 | |
564 | |
553 | This can be used to create timers that do not drift with respect |
565 | This can be used to create timers that do not drift with respect |
554 | to system time: |
566 | to system time: |
555 | |
567 | |
556 | my $hourly = EV::periodic 0, 3600, 0, sub { print "once/hour\n" }; |
568 | my $hourly = EV::periodic 0, 3600, 0, sub { print "once/hour\n" }; |
557 | |
569 | |
558 | That doesn't mean there will always be 3600 seconds in between |
570 | That doesn't mean there will always be 3600 seconds in between |
559 | triggers, but only that the the clalback will be called when the |
571 | triggers, but only that the the callback will be called when the |
560 | system time shows a full hour (UTC). |
572 | system time shows a full hour (UTC). |
561 | |
573 | |
562 | Another way to think about it (for the mathematically inclined) |
574 | Another way to think about it (for the mathematically inclined) |
563 | is that EV::periodic will try to run the callback in this mode |
575 | is that EV::periodic will try to run the callback in this mode |
564 | at the next possible time where "$time = $at (mod $interval)", |
576 | at the next possible time where "$time = $at (mod $interval)", |
… | |
… | |
572 | first, and the current time as second argument. |
584 | first, and the current time as second argument. |
573 | |
585 | |
574 | *This callback MUST NOT stop or destroy this or any other |
586 | *This callback MUST NOT stop or destroy this or any other |
575 | periodic watcher, ever, and MUST NOT call any event loop |
587 | periodic watcher, ever, and MUST NOT call any event loop |
576 | functions or methods*. If you need to stop it, return 1e30 and |
588 | functions or methods*. If you need to stop it, return 1e30 and |
577 | stop it afterwards. You may create and start a "EV::prepare" |
589 | stop it afterwards. You may create and start an "EV::prepare" |
578 | watcher for this task. |
590 | watcher for this task. |
579 | |
591 | |
580 | It must return the next time to trigger, based on the passed |
592 | It must return the next time to trigger, based on the passed |
581 | time value (that is, the lowest time value larger than or equal |
593 | time value (that is, the lowest time value larger than or equal |
582 | to to the second argument). It will usually be called just |
594 | to to the second argument). It will usually be called just |
583 | before the callback will be triggered, but might be called at |
595 | before the callback will be triggered, but might be called at |
584 | other times, too. |
596 | other times, too. |
585 | |
597 | |
586 | This can be used to create very complex timers, such as a timer |
598 | This can be used to create very complex timers, such as a timer |
587 | that triggers on each midnight, local time (actually 24 hours |
599 | that triggers on each midnight, local time (actually one day |
588 | after the last midnight, to keep the example simple. If you know |
600 | after the last midnight, to keep the example simple): |
589 | a way to do it correctly in about the same space (without |
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|
590 | requiring elaborate modules), drop me a note :): |
|
|
591 | |
601 | |
592 | my $daily = EV::periodic 0, 0, sub { |
602 | my $daily = EV::periodic 0, 0, sub { |
593 | my ($w, $now) = @_; |
603 | my ($w, $now) = @_; |
594 | |
604 | |
595 | use Time::Local (); |
605 | use Time::Local (); |
596 | my (undef, undef, undef, $d, $m, $y) = localtime $now; |
606 | my (undef, undef, undef, $d, $m, $y) = localtime $now; |
597 | 86400 + Time::Local::timelocal 0, 0, 0, $d, $m, $y |
607 | Time::Local::timelocal_nocheck 0, 0, 0, $d + 1, $m, $y |
598 | }, sub { |
608 | }, sub { |
599 | print "it's midnight or likely shortly after, now\n"; |
609 | print "it's midnight or likely shortly after, now\n"; |
600 | }; |
610 | }; |
601 | |
611 | |
602 | The "periodic_ns" variant doesn't start (activate) the newly created |
612 | The "periodic_ns" variant doesn't start (activate) the newly created |
… | |
… | |
925 | |
935 | |
926 | Please see the libev documentation for further details. |
936 | Please see the libev documentation for further details. |
927 | |
937 | |
928 | $w = EV::async $callback |
938 | $w = EV::async $callback |
929 | $w = EV::async_ns $callback |
939 | $w = EV::async_ns $callback |
|
|
940 | $w = $loop->async ($callback) |
|
|
941 | $w = $loop->async_ns ($callback) |
930 | $w->send |
942 | $w->send |
931 | $bool = $w->async_pending |
943 | $bool = $w->async_pending |
|
|
944 | |
|
|
945 | CLEANUP WATCHERS - how to clean up when the event loop goes away |
|
|
946 | Cleanup watchers are not supported on the Perl level, they can only be |
|
|
947 | used via XS currently. |
932 | |
948 | |
933 | PERL SIGNALS |
949 | PERL SIGNALS |
934 | While Perl signal handling (%SIG) is not affected by EV, the behaviour |
950 | While Perl signal handling (%SIG) is not affected by EV, the behaviour |
935 | with EV is as the same as any other C library: Perl-signals will only be |
951 | with EV is as the same as any other C library: Perl-signals will only be |
936 | handled when Perl runs, which means your signal handler might be invoked |
952 | handled when Perl runs, which means your signal handler might be invoked |