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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 |
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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) |
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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"). |
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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 | |
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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 | |
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530 | If called with a $repeat argument, then it uses this a timer repeat |
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531 | value. |
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532 | |
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533 | $after = $w->remaining |
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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, $callback) |
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… | |
545 | system time reaches or surpasses this time. |
556 | system time reaches or surpasses this time. |
546 | |
557 | |
547 | * repeating interval timer ($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 |
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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)", |
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… | |
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 :): |
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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 |
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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 |
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940 | $w = $loop->async ($callback) |
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941 | $w = $loop->async_ns ($callback) |
930 | $w->send |
942 | $w->send |
931 | $bool = $w->async_pending |
943 | $bool = $w->async_pending |
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944 | |
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945 | CLEANUP WATCHERS - how to clean up when the event loop goes away |
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946 | Cleanup watchers are not supported on the Perl level, they can only be |
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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 |