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Revision 1.144 by root, Sat Sep 6 18:42:18 2014 UTC vs.
Revision 1.162 by root, Wed Jan 22 23:17:31 2020 UTC

47 my ($w, $revents) = @_; 47 my ($w, $revents) = @_;
48 warn $w->path, " has changed somehow.\n"; 48 warn $w->path, " has changed somehow.\n";
49 }; 49 };
50 50
51 # MAINLOOP 51 # MAINLOOP
52 EV::run; # loop until EV::unloop is called or all watchers stop 52 EV::run; # loop until EV::break is called or all watchers stop
53 EV::run EV::RUN_ONCE; # block until at least one event could be handled 53 EV::run EV::RUN_ONCE; # block until at least one event could be handled
54 EV::run EV::RUN_NOWAIT; # try to handle same events, but do not block 54 EV::run EV::RUN_NOWAIT; # try to handle same events, but do not block
55 55
56=head1 BEFORE YOU START USING THIS MODULE 56=head1 BEFORE YOU START USING THIS MODULE
57 57
119package EV; 119package EV;
120 120
121use common::sense; 121use common::sense;
122 122
123BEGIN { 123BEGIN {
124 our $VERSION = '4.18'; 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::unloop 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 $old_repeat = $w->reapat ([$new_repeat])
652
653Returns the current value of the repeat attribute and optionally sets a
654new one. Setting the new one will not restart the watcher - if the watcher
655is active, the new repeat value is used whenever it expires next.
641 656
642=back 657=back
643 658
644 659
645=head3 PERIODIC WATCHERS - to cron or not to cron? 660=head3 PERIODIC WATCHERS - to cron or not to cron?
673surpasses this time. 688surpasses this time.
674 689
675=item * repeating interval timer ($interval > 0, $reschedule_cb = 0) 690=item * repeating interval timer ($interval > 0, $reschedule_cb = 0)
676 691
677In this mode the watcher will always be scheduled to time out at the 692In this mode the watcher will always be scheduled to time out at the
678next C<$at + N * $interval> time (for some integer N) and then repeat, 693next C<$at + N * $interval> time (for the lowest integer N) and then repeat,
679regardless of any time jumps. 694regardless of any time jumps. Note that, since C<N> can be negative, the
695first trigger can happen before C<$at>.
680 696
681This can be used to create timers that do not drift with respect to system 697This can be used to create timers that do not drift with respect to system
682time: 698time:
683 699
684 my $hourly = EV::periodic 0, 3600, 0, sub { print "once/hour\n" }; 700 my $hourly = EV::periodic 0, 3600, 0, sub { print "once/hour\n" };
700time as second argument. 716time as second argument.
701 717
702I<This callback MUST NOT stop or destroy this or any other periodic 718I<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 719watcher, 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 720you need to stop it, return 1e30 and stop it afterwards. You may create
705and start a C<EV::prepare> watcher for this task. 721and start an C<EV::prepare> watcher for this task.
706 722
707It must return the next time to trigger, based on the passed time value 723It 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 724(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 725argument). It will usually be called just before the callback will be
710triggered, but might be called at other times, too. 726triggered, but might be called at other times, too.
711 727
712This can be used to create very complex timers, such as a timer that 728This 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 729triggers 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 730midnight, to keep the example simple):
715in about the same space (without requiring elaborate modules), drop me a
716note :):
717 731
718 my $daily = EV::periodic 0, 0, sub { 732 my $daily = EV::periodic 0, 0, sub {
719 my ($w, $now) = @_; 733 my ($w, $now) = @_;
720 734
721 use Time::Local (); 735 use Time::Local ();
722 my (undef, undef, undef, $d, $m, $y) = localtime $now; 736 my (undef, undef, undef, $d, $m, $y) = localtime $now;
723 86400 + Time::Local::timelocal 0, 0, 0, $d, $m, $y 737 Time::Local::timelocal_nocheck 0, 0, 0, $d + 1, $m, $y
724 }, sub { 738 }, sub {
725 print "it's midnight or likely shortly after, now\n"; 739 print "it's midnight or likely shortly after, now\n";
726 }; 740 };
727 741
728=back 742=back
739Simply stops and starts the watcher again. 753Simply stops and starts the watcher again.
740 754
741=item $time = $w->at 755=item $time = $w->at
742 756
743Return the time that the watcher is expected to trigger next. 757Return the time that the watcher is expected to trigger next.
758
759=item $old_offset = $w->offset ([$new_offset])
760
761Returns the current value of the offset attribute and optionally sets a
762new one. Setting the new one will not restart the watcher - if the watcher
763is active, the new offset value is used whenever it expires next.
764
765=item $old_interval = $w->interval ([$new_interval])
766
767See above, for the interval attribute.
768
769=item $old_reschedule_cb = $w->reschedule_cb ([$new_reschedule_xcb])
770
771See above, for the reschedule callback.
744 772
745=back 773=back
746 774
747 775
748=head3 SIGNAL WATCHERS - signal me when a signal gets signalled! 776=head3 SIGNAL WATCHERS - signal me when a signal gets signalled!

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