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Revision 1.44 by root, Mon Jul 13 19:47:53 2015 UTC vs.
Revision 1.49 by root, Thu Oct 19 17:22:50 2023 UTC

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
236 (EV::BACKEND_SELECT or EV::BACKEND_EPOLL). 236 (EV::BACKEND_SELECT or EV::BACKEND_EPOLL).
237 237
238 $active = EV::run [$flags] 238 $active = EV::run [$flags]
239 $active = $loop->run ([$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::break or the flasg are nonzero (in which case the 241 callback calls EV::break or the flags are nonzero (in which case the
242 return value is true) or when there are no active watchers which 242 return value is true) or when there are no active watchers which
243 reference the loop (keepalive is true), in which case the return 243 reference the loop (keepalive is true), in which case the return
244 value will be false. The returnv alue can generally be interpreted 244 value will be false. The return value can generally be interpreted
245 as "if true, there is more work left to do". 245 as "if true, there is more work left to do".
246 246
247 The $flags argument can be one of the following: 247 The $flags argument can be one of the following:
248 248
249 0 as above 249 0 as above
251 EV::RUN_NOWAIT do not block at all (fetch/handle events but do not wait) 251 EV::RUN_NOWAIT do not block at all (fetch/handle events but do not wait)
252 252
253 EV::break [$how] 253 EV::break [$how]
254 $loop->break ([$how]) 254 $loop->break ([$how])
255 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
256 the innermost call to EV::loop return. 256 the innermost call to EV::run return.
257 257
258 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
259 will return as fast as possible. 259 will return as fast as possible.
260 260
261 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
262 will be cancelled. 262 will be cancelled.
263 263
276 "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
277 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
278 "undef" for $fh_or_undef and 0 for $events). 278 "undef" for $fh_or_undef and 0 for $events).
279 279
280 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.
281 Otherwise a EV::timer with this value will be started. 281 Otherwise an "EV::timer" with this value will be started.
282 282
283 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,
284 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
285 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",
286 "EV::READ", "EV::WRITE" and "EV::TIMER"). 286 "EV::READ", "EV::WRITE" and "EV::TIMER").
301 call as if the signal specified by $signal had occured. 301 call as if the signal specified by $signal had occured.
302 302
303 EV::feed_signal $signal 303 EV::feed_signal $signal
304 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
305 works regardless of which loop has registered the signal, and is 305 works regardless of which loop has registered the signal, and is
306 mainly useful fro custom signal implementations. 306 mainly useful for custom signal implementations.
307 307
308 EV::set_io_collect_interval $time 308 EV::set_io_collect_interval $time
309 $loop->set_io_collect_interval ($time) 309 $loop->set_io_collect_interval ($time)
310 EV::set_timeout_collect_interval $time 310 EV::set_timeout_collect_interval $time
311 $loop->set_timeout_collect_interval ($time) 311 $loop->set_timeout_collect_interval ($time)
414 If the watcher is pending, this function clears its pending status 414 If the watcher is pending, this function clears its pending status
415 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
416 the watcher isn't pending it does nothing and returns 0. 416 the watcher isn't pending it does nothing and returns 0.
417 417
418 $previous_state = $w->keepalive ($bool) 418 $previous_state = $w->keepalive ($bool)
419 Normally, "EV::loop" will return when there are no active watchers 419 Normally, "EV::run" will return when there are no active watchers
420 (which is a "deadlock" because no progress can be made anymore). 420 (which is a "deadlock" because no progress can be made anymore).
421 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
422 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
423 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
424 for their task :). 424 for their task :).
425 425
426 Sometimes, however, this gets in your way, for example when the 426 Sometimes, however, this gets in your way, for example when the
427 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
428 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
429 module written by somebody else even). Then you might want any 429 module written by somebody else even). Then you might want any
430 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
431 "EV::loop" from returning just because you happen to have this 431 "EV::run" from returning just because you happen to have this
432 long-running UDP port watcher. 432 long-running UDP port watcher.
433 433
434 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
435 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
436 returning. 436 returning.
437 437
438 The initial value for keepalive is true (enabled), and you can 438 The initial value for keepalive is true (enabled), and you can
439 change it any time. 439 change it any time.
440 440
482 TIMER WATCHERS - relative and optionally repeating timeouts 482 TIMER WATCHERS - relative and optionally repeating timeouts
483 $w = EV::timer $after, $repeat, $callback 483 $w = EV::timer $after, $repeat, $callback
484 $w = EV::timer_ns $after, $repeat, $callback 484 $w = EV::timer_ns $after, $repeat, $callback
485 $w = $loop->timer ($after, $repeat, $callback) 485 $w = $loop->timer ($after, $repeat, $callback)
486 $w = $loop->timer_ns ($after, $repeat, $callback) 486 $w = $loop->timer_ns ($after, $repeat, $callback)
487 Calls the callback after $after seconds (which may be fractional). 487 Calls the callback after $after seconds (which may be fractional or
488 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
489 $repeat value as $after) after the callback returns. 489 the $repeat value as $after) after the callback returns.
490 490
491 This means that the callback would be called roughly after $after 491 This means that the callback would be called roughly after $after
492 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
493 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
494 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
530 If called with a $repeat argument, then it uses this a timer repeat 530 If called with a $repeat argument, then it uses this a timer repeat
531 value. 531 value.
532 532
533 $after = $w->remaining 533 $after = $w->remaining
534 Calculates and returns the remaining time till the timer will fire. 534 Calculates and returns the remaining time till the timer will fire.
535
536 $repeat = $w->repeat
537 $old_repeat = $w->repeat ($new_repeat)
538 Returns the current value of the repeat attribute and optionally
539 sets a new one. Setting the new one will not restart the watcher -
540 if the watcher is active, the new repeat value is used whenever it
541 expires next.
535 542
536 PERIODIC WATCHERS - to cron or not to cron? 543 PERIODIC WATCHERS - to cron or not to cron?
537 $w = EV::periodic $at, $interval, $reschedule_cb, $callback 544 $w = EV::periodic $at, $interval, $reschedule_cb, $callback
538 $w = EV::periodic_ns $at, $interval, $reschedule_cb, $callback 545 $w = EV::periodic_ns $at, $interval, $reschedule_cb, $callback
539 $w = $loop->periodic ($at, $interval, $reschedule_cb, $callback) 546 $w = $loop->periodic ($at, $interval, $reschedule_cb, $callback)
556 system time reaches or surpasses this time. 563 system time reaches or surpasses this time.
557 564
558 * repeating interval timer ($interval > 0, $reschedule_cb = 0) 565 * repeating interval timer ($interval > 0, $reschedule_cb = 0)
559 566
560 In this mode the watcher will always be scheduled to time out at 567 In this mode the watcher will always be scheduled to time out at
561 the next "$at + N * $interval" time (for some integer N) and 568 the next "$at + N * $interval" time (for the lowest integer N)
562 then repeat, regardless of any time jumps. 569 and then repeat, regardless of any time jumps. Note that, since
570 "N" can be negative, the first trigger can happen before $at.
563 571
564 This can be used to create timers that do not drift with respect 572 This can be used to create timers that do not drift with respect
565 to system time: 573 to system time:
566 574
567 my $hourly = EV::periodic 0, 3600, 0, sub { print "once/hour\n" }; 575 my $hourly = EV::periodic 0, 3600, 0, sub { print "once/hour\n" };
583 first, and the current time as second argument. 591 first, and the current time as second argument.
584 592
585 *This callback MUST NOT stop or destroy this or any other 593 *This callback MUST NOT stop or destroy this or any other
586 periodic watcher, ever, and MUST NOT call any event loop 594 periodic watcher, ever, and MUST NOT call any event loop
587 functions or methods*. If you need to stop it, return 1e30 and 595 functions or methods*. If you need to stop it, return 1e30 and
588 stop it afterwards. You may create and start a "EV::prepare" 596 stop it afterwards. You may create and start an "EV::prepare"
589 watcher for this task. 597 watcher for this task.
590 598
591 It must return the next time to trigger, based on the passed 599 It must return the next time to trigger, based on the passed
592 time value (that is, the lowest time value larger than or equal 600 time value (that is, the lowest time value larger than or equal
593 to to the second argument). It will usually be called just 601 to to the second argument). It will usually be called just
594 before the callback will be triggered, but might be called at 602 before the callback will be triggered, but might be called at
595 other times, too. 603 other times, too.
596 604
597 This can be used to create very complex timers, such as a timer 605 This can be used to create very complex timers, such as a timer
598 that triggers on each midnight, local time (actually 24 hours 606 that triggers on each midnight, local time (actually one day
599 after the last midnight, to keep the example simple. If you know 607 after the last midnight, to keep the example simple):
600 a way to do it correctly in about the same space (without
601 requiring elaborate modules), drop me a note :):
602 608
603 my $daily = EV::periodic 0, 0, sub { 609 my $daily = EV::periodic 0, 0, sub {
604 my ($w, $now) = @_; 610 my ($w, $now) = @_;
605 611
606 use Time::Local (); 612 use Time::Local ();
607 my (undef, undef, undef, $d, $m, $y) = localtime $now; 613 my (undef, undef, undef, $d, $m, $y) = localtime $now;
608 86400 + Time::Local::timelocal 0, 0, 0, $d, $m, $y 614 Time::Local::timelocal_nocheck 0, 0, 0, $d + 1, $m, $y
609 }, sub { 615 }, sub {
610 print "it's midnight or likely shortly after, now\n"; 616 print "it's midnight or likely shortly after, now\n";
611 }; 617 };
612 618
613 The "periodic_ns" variant doesn't start (activate) the newly created 619 The "periodic_ns" variant doesn't start (activate) the newly created
620 $w->again 626 $w->again
621 Simply stops and starts the watcher again. 627 Simply stops and starts the watcher again.
622 628
623 $time = $w->at 629 $time = $w->at
624 Return the time that the watcher is expected to trigger next. 630 Return the time that the watcher is expected to trigger next.
631
632 $offset = $w->offset
633 $old_offset = $w->offset ($new_offset)
634 Returns the current value of the offset attribute and optionally
635 sets a new one. Setting the new one will not restart the watcher -
636 if the watcher is active, the new offset value is used whenever it
637 expires next.
638
639 $interval = $w->interval
640 $old_interval = $w->interval ($new_interval)
641 See above, for the interval attribute.
642
643 $reschedule_cb = $w->reschedule_cb
644 $old_reschedule_cb = $w->reschedule_cb ($new_reschedule_cb)
645 See above, for the reschedule callback.
625 646
626 SIGNAL WATCHERS - signal me when a signal gets signalled! 647 SIGNAL WATCHERS - signal me when a signal gets signalled!
627 $w = EV::signal $signal, $callback 648 $w = EV::signal $signal, $callback
628 $w = EV::signal_ns $signal, $callback 649 $w = EV::signal_ns $signal, $callback
629 $w = $loop->signal ($signal, $callback) 650 $w = $loop->signal ($signal, $callback)
694 entry in perlfunc). 715 entry in perlfunc).
695 716
696 $pid = $w->rpid 717 $pid = $w->rpid
697 Return the pid of the awaited child (useful when you have installed 718 Return the pid of the awaited child (useful when you have installed
698 a watcher for all pids). 719 a watcher for all pids).
720
721 EV::Child::reinit [EXPERIMENTAL]
722 Internally, libev installs a signal handler for "SIGCHLD".
723 Unfortunately, a lot of Perl code does soemthing like "local
724 $SIG{CHLD}", which, unfortunately, is broken and will not restore
725 the signal handler.
726
727 If this has happened, you can call this function to stop/rrestart
728 the internal libev watcher, which will reset the signal handler.
729
730 Note that this is an experimental function, whose interface might
731 change.
699 732
700 STAT WATCHERS - did the file attributes just change? 733 STAT WATCHERS - did the file attributes just change?
701 $w = EV::stat $path, $interval, $callback 734 $w = EV::stat $path, $interval, $callback
702 $w = EV::stat_ns $path, $interval, $callback 735 $w = EV::stat_ns $path, $interval, $callback
703 $w = $loop->stat ($path, $interval, $callback) 736 $w = $loop->stat ($path, $interval, $callback)

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