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Comparing EV/EV.pm (file contents):
Revision 1.146 by root, Sat Jun 20 11:11:01 2015 UTC vs.
Revision 1.163 by root, Thu Jan 23 12:49:13 2020 UTC

119package EV; 119package EV;
120 120
121use common::sense; 121use common::sense;
122 122
123BEGIN { 123BEGIN {
124 our $VERSION = '4.20'; 124 our $VERSION = '4.31';
125 use XSLoader; 125 use XSLoader;
126 local $^W = 0; # avoid spurious warning 126 local $^W = 0; # avoid spurious warning
127 XSLoader::load "EV", $VERSION; 127 XSLoader::load "EV", $VERSION;
128} 128}
129 129
248 248
249=item $loop->now_update 249=item $loop->now_update
250 250
251Establishes the current time by querying the kernel, updating the time 251Establishes the current time by querying the kernel, updating the time
252returned by C<EV::now> in the progress. This is a costly operation and 252returned by C<EV::now> in the progress. This is a costly operation and
253is usually done automatically within C<EV::loop>. 253is usually done automatically within C<EV::run>.
254 254
255This function is rarely useful, but when some event callback runs for a 255This function is rarely useful, but when some event callback runs for a
256very long time without entering the event loop, updating libev's idea of 256very long time without entering the event loop, updating libev's idea of
257the current time is a good idea. 257the current time is a good idea.
258 258
296=item $active = EV::run [$flags] 296=item $active = EV::run [$flags]
297 297
298=item $active = $loop->run ([$flags]) 298=item $active = $loop->run ([$flags])
299 299
300Begin checking for events and calling callbacks. It returns when a 300Begin checking for events and calling callbacks. It returns when a
301callback calls EV::break or the flasg are nonzero (in which case the 301callback calls EV::break or the flags are nonzero (in which case the
302return value is true) or when there are no active watchers which reference 302return value is true) or when there are no active watchers which reference
303the loop (keepalive is true), in which case the return value will be 303the loop (keepalive is true), in which case the return value will be
304false. The returnv alue can generally be interpreted as "if true, there is 304false. The return value can generally be interpreted as "if true, there is
305more work left to do". 305more work left to do".
306 306
307The $flags argument can be one of the following: 307The $flags argument can be one of the following:
308 308
309 0 as above 309 0 as above
313=item EV::break [$how] 313=item EV::break [$how]
314 314
315=item $loop->break ([$how]) 315=item $loop->break ([$how])
316 316
317When called with no arguments or an argument of EV::BREAK_ONE, makes the 317When called with no arguments or an argument of EV::BREAK_ONE, makes the
318innermost call to EV::loop return. 318innermost call to EV::run return.
319 319
320When called with an argument of EV::BREAK_ALL, all calls to EV::loop will 320When called with an argument of EV::BREAK_ALL, all calls to EV::run will
321return as fast as possible. 321return as fast as possible.
322 322
323When called with an argument of EV::BREAK_CANCEL, any pending break will 323When called with an argument of EV::BREAK_CANCEL, any pending break will
324be cancelled. 324be cancelled.
325 325
342| EV::WRITE>, indicating the type of I/O event you want to wait for. If 342| EV::WRITE>, indicating the type of I/O event you want to wait for. If
343you do not want to wait for some I/O event, specify C<undef> for 343you do not want to wait for some I/O event, specify C<undef> for
344C<$fh_or_undef> and C<0> for C<$events>). 344C<$fh_or_undef> and C<0> for C<$events>).
345 345
346If timeout is C<undef> or negative, then there will be no 346If timeout is C<undef> or negative, then there will be no
347timeout. Otherwise a EV::timer with this value will be started. 347timeout. Otherwise an C<EV::timer> with this value will be started.
348 348
349When an error occurs or either the timeout or I/O watcher triggers, then 349When an error occurs or either the timeout or I/O watcher triggers, then
350the callback will be called with the received event set (in general 350the callback will be called with the received event set (in general
351you can expect it to be a combination of C<EV::ERROR>, C<EV::READ>, 351you can expect it to be a combination of C<EV::ERROR>, C<EV::READ>,
352C<EV::WRITE> and C<EV::TIMER>). 352C<EV::WRITE> and C<EV::TIMER>).
370 370
371=item EV::feed_signal $signal 371=item EV::feed_signal $signal
372 372
373Feed a signal event into EV - unlike C<EV::feed_signal_event>, this works 373Feed a signal event into EV - unlike C<EV::feed_signal_event>, this works
374regardless of which loop has registered the signal, and is mainly useful 374regardless of which loop has registered the signal, and is mainly useful
375fro custom signal implementations. 375for custom signal implementations.
376 376
377=item EV::set_io_collect_interval $time 377=item EV::set_io_collect_interval $time
378 378
379=item $loop->set_io_collect_interval ($time) 379=item $loop->set_io_collect_interval ($time)
380 380
507returns its C<$revents> bitset (as if its callback was invoked). If the 507returns its C<$revents> bitset (as if its callback was invoked). If the
508watcher isn't pending it does nothing and returns C<0>. 508watcher isn't pending it does nothing and returns C<0>.
509 509
510=item $previous_state = $w->keepalive ($bool) 510=item $previous_state = $w->keepalive ($bool)
511 511
512Normally, C<EV::loop> will return when there are no active watchers 512Normally, C<EV::run> will return when there are no active watchers
513(which is a "deadlock" because no progress can be made anymore). This is 513(which is a "deadlock" because no progress can be made anymore). This is
514convenient because it allows you to start your watchers (and your jobs), 514convenient because it allows you to start your watchers (and your jobs),
515call C<EV::loop> once and when it returns you know that all your jobs are 515call C<EV::run> once and when it returns you know that all your jobs are
516finished (or they forgot to register some watchers for their task :). 516finished (or they forgot to register some watchers for their task :).
517 517
518Sometimes, however, this gets in your way, for example when the module 518Sometimes, however, this gets in your way, for example when the module
519that calls C<EV::loop> (usually the main program) is not the same module 519that calls C<EV::run> (usually the main program) is not the same module
520as a long-living watcher (for example a DNS client module written by 520as a long-living watcher (for example a DNS client module written by
521somebody else even). Then you might want any outstanding requests to be 521somebody else even). Then you might want any outstanding requests to be
522handled, but you would not want to keep C<EV::loop> from returning just 522handled, but you would not want to keep C<EV::run> from returning just
523because you happen to have this long-running UDP port watcher. 523because you happen to have this long-running UDP port watcher.
524 524
525In this case you can clear the keepalive status, which means that even 525In this case you can clear the keepalive status, which means that even
526though your watcher is active, it won't keep C<EV::loop> from returning. 526though your watcher is active, it won't keep C<EV::run> from returning.
527 527
528The initial value for keepalive is true (enabled), and you can change it 528The initial value for keepalive is true (enabled), and you can change it
529any time. 529any time.
530 530
531Example: Register an I/O watcher for some UDP socket but do not keep the 531Example: Register an I/O watcher for some UDP socket but do not keep the
598 598
599=item $w = $loop->timer ($after, $repeat, $callback) 599=item $w = $loop->timer ($after, $repeat, $callback)
600 600
601=item $w = $loop->timer_ns ($after, $repeat, $callback) 601=item $w = $loop->timer_ns ($after, $repeat, $callback)
602 602
603Calls the callback after C<$after> seconds (which may be fractional). If 603Calls the callback after C<$after> seconds (which may be fractional or
604C<$repeat> is non-zero, the timer will be restarted (with the $repeat 604negative). If C<$repeat> is non-zero, the timer will be restarted (with
605value as $after) after the callback returns. 605the $repeat value as $after) after the callback returns.
606 606
607This means that the callback would be called roughly after C<$after> 607This means that the callback would be called roughly after C<$after>
608seconds, and then every C<$repeat> seconds. The timer does his best not 608seconds, and then every C<$repeat> seconds. The timer does his best not
609to drift, but it will not invoke the timer more often then once per event 609to drift, but it will not invoke the timer more often then once per event
610loop iteration, and might drift in other cases. If that isn't acceptable, 610loop iteration, and might drift in other cases. If that isn't acceptable,
614in front of the machine while the timer is running and changes the system 614in front of the machine while the timer is running and changes the system
615clock, the timer will nevertheless run (roughly) the same time. 615clock, the timer will nevertheless run (roughly) the same time.
616 616
617The C<timer_ns> variant doesn't start (activate) the newly created watcher. 617The C<timer_ns> variant doesn't start (activate) the newly created watcher.
618 618
619=item $w->set ($after, $repeat) 619=item $w->set ($after, $repeat = 0)
620 620
621Reconfigures the watcher, see the constructor above for details. Can be called at 621Reconfigures the watcher, see the constructor above for details. Can be called at
622any time. 622any time.
623 623
624=item $w->again 624=item $w->again
625
626=item $w->again ($repeat)
625 627
626Similar to the C<start> method, but has special semantics for repeating timers: 628Similar to the C<start> method, but has special semantics for repeating timers:
627 629
628If the timer is active and non-repeating, it will be stopped. 630If the timer is active and non-repeating, it will be stopped.
629 631
636 638
637This behaviour is useful when you have a timeout for some IO 639This behaviour is useful when you have a timeout for some IO
638operation. You create a timer object with the same value for C<$after> and 640operation. You create a timer object with the same value for C<$after> and
639C<$repeat>, and then, in the read/write watcher, run the C<again> method 641C<$repeat>, and then, in the read/write watcher, run the C<again> method
640on the timeout. 642on the timeout.
643
644If called with a C<$repeat> argument, then it uses this a timer repeat
645value.
646
647=item $after = $w->remaining
648
649Calculates and returns the remaining time till the timer will fire.
650
651=item $repeat = $w->repeat
652
653=item $old_repeat = $w->repeat ($new_repeat)
654
655Returns the current value of the repeat attribute and optionally sets a
656new one. Setting the new one will not restart the watcher - if the watcher
657is active, the new repeat value is used whenever it expires next.
641 658
642=back 659=back
643 660
644 661
645=head3 PERIODIC WATCHERS - to cron or not to cron? 662=head3 PERIODIC WATCHERS - to cron or not to cron?
673surpasses this time. 690surpasses this time.
674 691
675=item * repeating interval timer ($interval > 0, $reschedule_cb = 0) 692=item * repeating interval timer ($interval > 0, $reschedule_cb = 0)
676 693
677In this mode the watcher will always be scheduled to time out at the 694In this mode the watcher will always be scheduled to time out at the
678next C<$at + N * $interval> time (for some integer N) and then repeat, 695next C<$at + N * $interval> time (for the lowest integer N) and then repeat,
679regardless of any time jumps. 696regardless of any time jumps. Note that, since C<N> can be negative, the
697first trigger can happen before C<$at>.
680 698
681This can be used to create timers that do not drift with respect to system 699This can be used to create timers that do not drift with respect to system
682time: 700time:
683 701
684 my $hourly = EV::periodic 0, 3600, 0, sub { print "once/hour\n" }; 702 my $hourly = EV::periodic 0, 3600, 0, sub { print "once/hour\n" };
700time as second argument. 718time as second argument.
701 719
702I<This callback MUST NOT stop or destroy this or any other periodic 720I<This callback MUST NOT stop or destroy this or any other periodic
703watcher, ever, and MUST NOT call any event loop functions or methods>. If 721watcher, ever, and MUST NOT call any event loop functions or methods>. If
704you need to stop it, return 1e30 and stop it afterwards. You may create 722you need to stop it, return 1e30 and stop it afterwards. You may create
705and start a C<EV::prepare> watcher for this task. 723and start an C<EV::prepare> watcher for this task.
706 724
707It must return the next time to trigger, based on the passed time value 725It must return the next time to trigger, based on the passed time value
708(that is, the lowest time value larger than or equal to to the second 726(that is, the lowest time value larger than or equal to to the second
709argument). It will usually be called just before the callback will be 727argument). It will usually be called just before the callback will be
710triggered, but might be called at other times, too. 728triggered, but might be called at other times, too.
711 729
712This can be used to create very complex timers, such as a timer that 730This can be used to create very complex timers, such as a timer that
713triggers on each midnight, local time (actually 24 hours after the last 731triggers on each midnight, local time (actually one day after the last
714midnight, to keep the example simple. If you know a way to do it correctly 732midnight, to keep the example simple):
715in about the same space (without requiring elaborate modules), drop me a
716note :):
717 733
718 my $daily = EV::periodic 0, 0, sub { 734 my $daily = EV::periodic 0, 0, sub {
719 my ($w, $now) = @_; 735 my ($w, $now) = @_;
720 736
721 use Time::Local (); 737 use Time::Local ();
722 my (undef, undef, undef, $d, $m, $y) = localtime $now; 738 my (undef, undef, undef, $d, $m, $y) = localtime $now;
723 86400 + Time::Local::timelocal 0, 0, 0, $d, $m, $y 739 Time::Local::timelocal_nocheck 0, 0, 0, $d + 1, $m, $y
724 }, sub { 740 }, sub {
725 print "it's midnight or likely shortly after, now\n"; 741 print "it's midnight or likely shortly after, now\n";
726 }; 742 };
727 743
728=back 744=back
739Simply stops and starts the watcher again. 755Simply stops and starts the watcher again.
740 756
741=item $time = $w->at 757=item $time = $w->at
742 758
743Return the time that the watcher is expected to trigger next. 759Return the time that the watcher is expected to trigger next.
760
761=item $offset = $w->offset
762
763=item $old_offset = $w->offset ($new_offset)
764
765Returns the current value of the offset attribute and optionally sets a
766new one. Setting the new one will not restart the watcher - if the watcher
767is active, the new offset value is used whenever it expires next.
768
769=item $interval = $w->interval
770
771=item $old_interval = $w->interval ($new_interval)
772
773See above, for the interval attribute.
774
775=item $reschedule_cb = $w->reschedule_cb
776
777=item $old_reschedule_cb = $w->reschedule_cb ($new_reschedule_cb)
778
779See above, for the reschedule callback.
744 780
745=back 781=back
746 782
747 783
748=head3 SIGNAL WATCHERS - signal me when a signal gets signalled! 784=head3 SIGNAL WATCHERS - signal me when a signal gets signalled!

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