… | |
… | |
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::loop; # 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::loop EV::LOOP_ONESHOT; # 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::loop EV::LOOP_NONBLOCK; # try to handle same events, but do not block |
54 | EV::run EV::RUN_NOWAIT; # try to handle same events, but do not block |
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55 | |
|
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56 | =head1 BEFORE YOU START USING THIS MODULE |
|
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57 | |
|
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58 | If you only need timer, I/O, signal, child and idle watchers and not the |
|
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59 | advanced functionality of this module, consider using L<AnyEvent> instead, |
|
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60 | specifically the simplified API described in L<AE>. |
|
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61 | |
|
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62 | When used with EV as backend, the L<AE> API is as fast as the native L<EV> |
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63 | API, but your programs/modules will still run with many other event loops. |
55 | |
64 | |
56 | =head1 DESCRIPTION |
65 | =head1 DESCRIPTION |
57 | |
66 | |
58 | This module provides an interface to libev |
67 | This module provides an interface to libev |
59 | (L<http://software.schmorp.de/pkg/libev.html>). While the documentation |
68 | (L<http://software.schmorp.de/pkg/libev.html>). While the documentation |
… | |
… | |
68 | can use it through the L<AnyEvent> module, stay portable to other event |
77 | can use it through the L<AnyEvent> module, stay portable to other event |
69 | loops (if you don't rely on any watcher types not available through it) |
78 | loops (if you don't rely on any watcher types not available through it) |
70 | and still be faster than with any other event loop currently supported in |
79 | and still be faster than with any other event loop currently supported in |
71 | Perl. |
80 | Perl. |
72 | |
81 | |
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82 | =head2 PORTING FROM EV 3.X to 4.X |
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83 | |
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84 | EV version 4 introduces a number of incompatible changes summarised |
|
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85 | here. According to the depreciation strategy used by libev, there is a |
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86 | compatibility layer in place so programs should continue to run unchanged |
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87 | (the XS interface lacks this layer, so programs using that one need to be |
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88 | updated). |
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89 | |
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90 | This compatibility layer will be switched off in some future release. |
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91 | |
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92 | All changes relevant to Perl are renames of symbols, functions and |
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93 | methods: |
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94 | |
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95 | EV::loop => EV::run |
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96 | EV::LOOP_NONBLOCK => EV::RUN_NOWAIT |
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97 | EV::LOOP_ONESHOT => EV::RUN_ONCE |
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98 | |
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99 | EV::unloop => EV::break |
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100 | EV::UNLOOP_CANCEL => EV::BREAK_CANCEL |
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101 | EV::UNLOOP_ONE => EV::BREAK_ONE |
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102 | EV::UNLOOP_ALL => EV::BREAK_ALL |
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103 | |
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104 | EV::TIMEOUT => EV::TIMER |
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105 | |
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106 | EV::loop_count => EV::iteration |
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107 | EV::loop_depth => EV::depth |
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108 | EV::loop_verify => EV::verify |
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109 | |
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110 | The loop object methods corresponding to the functions above have been |
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111 | similarly renamed. |
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112 | |
73 | =head2 MODULE EXPORTS |
113 | =head2 MODULE EXPORTS |
74 | |
114 | |
75 | This module does not export any symbols. |
115 | This module does not export any symbols. |
76 | |
116 | |
77 | =cut |
117 | =cut |
… | |
… | |
79 | package EV; |
119 | package EV; |
80 | |
120 | |
81 | use common::sense; |
121 | use common::sense; |
82 | |
122 | |
83 | BEGIN { |
123 | BEGIN { |
84 | our $VERSION = '3.7'; |
124 | our $VERSION = '4.32'; |
85 | use XSLoader; |
125 | use XSLoader; |
|
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126 | local $^W = 0; # avoid spurious warning |
86 | XSLoader::load "EV", $VERSION; |
127 | XSLoader::load "EV", $VERSION; |
87 | } |
128 | } |
88 | |
129 | |
89 | @EV::IO::ISA = |
130 | @EV::IO::ISA = |
90 | @EV::Timer::ISA = |
131 | @EV::Timer::ISA = |
… | |
… | |
146 | Must be called after a fork in the child, before entering or continuing |
187 | Must be called after a fork in the child, before entering or continuing |
147 | the event loop. An alternative is to use C<EV::FLAG_FORKCHECK> which calls |
188 | the event loop. An alternative is to use C<EV::FLAG_FORKCHECK> which calls |
148 | this function automatically, at some performance loss (refer to the libev |
189 | this function automatically, at some performance loss (refer to the libev |
149 | documentation). |
190 | documentation). |
150 | |
191 | |
151 | =item $loop->loop_verify |
192 | =item $loop->verify |
152 | |
193 | |
153 | Calls C<ev_verify> to make internal consistency checks (for debugging |
194 | Calls C<ev_verify> to make internal consistency checks (for debugging |
154 | libev) and abort the program if any data structures were found to be |
195 | libev) and abort the program if any data structures were found to be |
155 | corrupted. |
196 | corrupted. |
156 | |
197 | |
… | |
… | |
207 | |
248 | |
208 | =item $loop->now_update |
249 | =item $loop->now_update |
209 | |
250 | |
210 | Establishes the current time by querying the kernel, updating the time |
251 | Establishes the current time by querying the kernel, updating the time |
211 | returned by C<EV::now> in the progress. This is a costly operation and |
252 | returned by C<EV::now> in the progress. This is a costly operation and |
212 | is usually done automatically within C<EV::loop>. |
253 | is usually done automatically within C<EV::run>. |
213 | |
254 | |
214 | This function is rarely useful, but when some event callback runs for a |
255 | This function is rarely useful, but when some event callback runs for a |
215 | very long time without entering the event loop, updating libev's idea of |
256 | very long time without entering the event loop, updating libev's idea of |
216 | the current time is a good idea. |
257 | the current time is a good idea. |
217 | |
258 | |
… | |
… | |
250 | =item $backend = $loop->backend |
291 | =item $backend = $loop->backend |
251 | |
292 | |
252 | Returns an integer describing the backend used by libev (EV::BACKEND_SELECT |
293 | Returns an integer describing the backend used by libev (EV::BACKEND_SELECT |
253 | or EV::BACKEND_EPOLL). |
294 | or EV::BACKEND_EPOLL). |
254 | |
295 | |
255 | =item EV::loop [$flags] |
296 | =item $active = EV::run [$flags] |
256 | |
297 | |
257 | =item $loop->loop ([$flags]) |
298 | =item $active = $loop->run ([$flags]) |
258 | |
299 | |
259 | Begin checking for events and calling callbacks. It returns when a |
300 | Begin checking for events and calling callbacks. It returns when a |
260 | callback calls EV::unloop. |
301 | callback calls EV::break or the flags are nonzero (in which case the |
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302 | return value is true) or when there are no active watchers which reference |
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303 | the loop (keepalive is true), in which case the return value will be |
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304 | false. The return value can generally be interpreted as "if true, there is |
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305 | more work left to do". |
261 | |
306 | |
262 | The $flags argument can be one of the following: |
307 | The $flags argument can be one of the following: |
263 | |
308 | |
264 | 0 as above |
309 | 0 as above |
265 | EV::LOOP_ONESHOT block at most once (wait, but do not loop) |
310 | EV::RUN_ONCE block at most once (wait, but do not loop) |
266 | EV::LOOP_NONBLOCK do not block at all (fetch/handle events but do not wait) |
311 | EV::RUN_NOWAIT do not block at all (fetch/handle events but do not wait) |
267 | |
312 | |
268 | =item EV::unloop [$how] |
313 | =item EV::break [$how] |
269 | |
314 | |
270 | =item $loop->unloop ([$how]) |
315 | =item $loop->break ([$how]) |
271 | |
316 | |
272 | When called with no arguments or an argument of EV::UNLOOP_ONE, makes the |
317 | When called with no arguments or an argument of EV::BREAK_ONE, makes the |
273 | innermost call to EV::loop return. |
318 | innermost call to EV::run return. |
274 | |
319 | |
275 | When called with an argument of EV::UNLOOP_ALL, all calls to EV::loop will return as |
320 | When called with an argument of EV::BREAK_ALL, all calls to EV::run will |
276 | fast as possible. |
321 | return as fast as possible. |
277 | |
322 | |
278 | =item $count = EV::loop_count |
323 | When called with an argument of EV::BREAK_CANCEL, any pending break will |
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324 | be cancelled. |
279 | |
325 | |
|
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326 | =item $count = EV::iteration |
|
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327 | |
280 | =item $count = $loop->loop_count |
328 | =item $count = $loop->iteration |
281 | |
329 | |
282 | Return the number of times the event loop has polled for new |
330 | Return the number of times the event loop has polled for new |
283 | events. Sometimes useful as a generation counter. |
331 | events. Sometimes useful as a generation counter. |
284 | |
332 | |
285 | =item EV::once $fh_or_undef, $events, $timeout, $cb->($revents) |
333 | =item EV::once $fh_or_undef, $events, $timeout, $cb->($revents) |
… | |
… | |
294 | | 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 |
295 | you do not want to wait for some I/O event, specify C<undef> for |
343 | you do not want to wait for some I/O event, specify C<undef> for |
296 | C<$fh_or_undef> and C<0> for C<$events>). |
344 | C<$fh_or_undef> and C<0> for C<$events>). |
297 | |
345 | |
298 | If timeout is C<undef> or negative, then there will be no |
346 | If timeout is C<undef> or negative, then there will be no |
299 | timeout. Otherwise a EV::timer with this value will be started. |
347 | timeout. Otherwise an C<EV::timer> with this value will be started. |
300 | |
348 | |
301 | When an error occurs or either the timeout or I/O watcher triggers, then |
349 | When an error occurs or either the timeout or I/O watcher triggers, then |
302 | the callback will be called with the received event set (in general |
350 | the callback will be called with the received event set (in general |
303 | you can expect it to be a combination of C<EV::ERROR>, C<EV::READ>, |
351 | you can expect it to be a combination of C<EV::ERROR>, C<EV::READ>, |
304 | C<EV::WRITE> and C<EV::TIMEOUT>). |
352 | C<EV::WRITE> and C<EV::TIMER>). |
305 | |
353 | |
306 | EV::once doesn't return anything: the watchers stay active till either |
354 | EV::once doesn't return anything: the watchers stay active till either |
307 | of them triggers, then they will be stopped and freed, and the callback |
355 | of them triggers, then they will be stopped and freed, and the callback |
308 | invoked. |
356 | invoked. |
309 | |
357 | |
310 | =item EV::feed_fd_event ($fd, $revents) |
358 | =item EV::feed_fd_event $fd, $revents |
311 | |
359 | |
312 | =item $loop->feed_fd_event ($fd, $revents) |
360 | =item $loop->feed_fd_event ($fd, $revents) |
313 | |
361 | |
314 | Feed an event on a file descriptor into EV. EV will react to this call as |
362 | Feed an event on a file descriptor into EV. EV will react to this call as |
315 | if the readyness notifications specified by C<$revents> (a combination of |
363 | if the readyness notifications specified by C<$revents> (a combination of |
316 | C<EV::READ> and C<EV::WRITE>) happened on the file descriptor C<$fd>. |
364 | C<EV::READ> and C<EV::WRITE>) happened on the file descriptor C<$fd>. |
317 | |
365 | |
318 | =item EV::feed_signal_event ($signal) |
366 | =item EV::feed_signal_event $signal |
319 | |
367 | |
320 | Feed a signal event into EV. EV will react to this call as if the signal |
368 | Feed a signal event into the default loop. EV will react to this call as |
321 | specified by C<$signal> had occured. |
369 | if the signal specified by C<$signal> had occured. |
|
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370 | |
|
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371 | =item EV::feed_signal $signal |
|
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372 | |
|
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373 | Feed a signal event into EV - unlike C<EV::feed_signal_event>, this works |
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374 | regardless of which loop has registered the signal, and is mainly useful |
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375 | for custom signal implementations. |
322 | |
376 | |
323 | =item EV::set_io_collect_interval $time |
377 | =item EV::set_io_collect_interval $time |
324 | |
378 | |
325 | =item $loop->set_io_collect_interval ($time) |
379 | =item $loop->set_io_collect_interval ($time) |
326 | |
380 | |
… | |
… | |
331 | These advanced functions set the minimum block interval when polling for I/O events and the minimum |
385 | These advanced functions set the minimum block interval when polling for I/O events and the minimum |
332 | wait interval for timer events. See the libev documentation at |
386 | wait interval for timer events. See the libev documentation at |
333 | L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#FUNCTIONS_CONTROLLING_THE_EVENT_LOOP> |
387 | L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#FUNCTIONS_CONTROLLING_THE_EVENT_LOOP> |
334 | (locally installed as F<EV::libev>) for a more detailed discussion. |
388 | (locally installed as F<EV::libev>) for a more detailed discussion. |
335 | |
389 | |
|
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390 | =item $count = EV::pending_count |
|
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391 | |
|
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392 | =item $count = $loop->pending_count |
|
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393 | |
|
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394 | Returns the number of currently pending watchers. |
|
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395 | |
|
|
396 | =item EV::invoke_pending |
|
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397 | |
|
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398 | =item $loop->invoke_pending |
|
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399 | |
|
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400 | Invoke all currently pending watchers. |
|
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401 | |
336 | =back |
402 | =back |
337 | |
403 | |
338 | |
404 | |
339 | =head1 WATCHER OBJECTS |
405 | =head1 WATCHER OBJECTS |
340 | |
406 | |
… | |
… | |
354 | |
420 | |
355 | Each watcher type has its associated bit in revents, so you can use the |
421 | Each watcher type has its associated bit in revents, so you can use the |
356 | same callback for multiple watchers. The event mask is named after the |
422 | same callback for multiple watchers. The event mask is named after the |
357 | type, i.e. EV::child sets EV::CHILD, EV::prepare sets EV::PREPARE, |
423 | type, i.e. EV::child sets EV::CHILD, EV::prepare sets EV::PREPARE, |
358 | EV::periodic sets EV::PERIODIC and so on, with the exception of I/O events |
424 | EV::periodic sets EV::PERIODIC and so on, with the exception of I/O events |
359 | (which can set both EV::READ and EV::WRITE bits), and EV::timer (which |
425 | (which can set both EV::READ and EV::WRITE bits). |
360 | uses EV::TIMEOUT). |
|
|
361 | |
426 | |
362 | In the rare case where one wants to create a watcher but not start it at |
427 | In the rare case where one wants to create a watcher but not start it at |
363 | the same time, each constructor has a variant with a trailing C<_ns> in |
428 | the same time, each constructor has a variant with a trailing C<_ns> in |
364 | its name, e.g. EV::io has a non-starting variant EV::io_ns and so on. |
429 | its name, e.g. EV::io has a non-starting variant EV::io_ns and so on. |
365 | |
430 | |
… | |
… | |
442 | returns its C<$revents> bitset (as if its callback was invoked). If the |
507 | returns its C<$revents> bitset (as if its callback was invoked). If the |
443 | watcher isn't pending it does nothing and returns C<0>. |
508 | watcher isn't pending it does nothing and returns C<0>. |
444 | |
509 | |
445 | =item $previous_state = $w->keepalive ($bool) |
510 | =item $previous_state = $w->keepalive ($bool) |
446 | |
511 | |
447 | Normally, C<EV::loop> will return when there are no active watchers |
512 | Normally, C<EV::run> will return when there are no active watchers |
448 | (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 |
449 | convinient because it allows you to start your watchers (and your jobs), |
514 | convenient because it allows you to start your watchers (and your jobs), |
450 | call C<EV::loop> once and when it returns you know that all your jobs are |
515 | call C<EV::run> once and when it returns you know that all your jobs are |
451 | finished (or they forgot to register some watchers for their task :). |
516 | finished (or they forgot to register some watchers for their task :). |
452 | |
517 | |
453 | Sometimes, however, this gets in your way, for example when the module |
518 | Sometimes, however, this gets in your way, for example when the module |
454 | that calls C<EV::loop> (usually the main program) is not the same module |
519 | that calls C<EV::run> (usually the main program) is not the same module |
455 | as a long-living watcher (for example a DNS client module written by |
520 | as a long-living watcher (for example a DNS client module written by |
456 | somebody else even). Then you might want any outstanding requests to be |
521 | somebody else even). Then you might want any outstanding requests to be |
457 | handled, but you would not want to keep C<EV::loop> from returning just |
522 | handled, but you would not want to keep C<EV::run> from returning just |
458 | because you happen to have this long-running UDP port watcher. |
523 | because you happen to have this long-running UDP port watcher. |
459 | |
524 | |
460 | In this case you can clear the keepalive status, which means that even |
525 | In this case you can clear the keepalive status, which means that even |
461 | though your watcher is active, it won't keep C<EV::loop> from returning. |
526 | though your watcher is active, it won't keep C<EV::run> from returning. |
462 | |
527 | |
463 | The initial value for keepalive is true (enabled), and you can change it |
528 | The initial value for keepalive is true (enabled), and you can change it |
464 | any time. |
529 | any time. |
465 | |
530 | |
466 | Example: Register an I/O watcher for some UDP socket but do not keep the |
531 | Example: Register an I/O watcher for some UDP socket but do not keep the |
… | |
… | |
533 | |
598 | |
534 | =item $w = $loop->timer ($after, $repeat, $callback) |
599 | =item $w = $loop->timer ($after, $repeat, $callback) |
535 | |
600 | |
536 | =item $w = $loop->timer_ns ($after, $repeat, $callback) |
601 | =item $w = $loop->timer_ns ($after, $repeat, $callback) |
537 | |
602 | |
538 | Calls the callback after C<$after> seconds (which may be fractional). If |
603 | Calls the callback after C<$after> seconds (which may be fractional or |
539 | C<$repeat> is non-zero, the timer will be restarted (with the $repeat |
604 | negative). If C<$repeat> is non-zero, the timer will be restarted (with |
540 | value as $after) after the callback returns. |
605 | the $repeat value as $after) after the callback returns. |
541 | |
606 | |
542 | This means that the callback would be called roughly after C<$after> |
607 | This means that the callback would be called roughly after C<$after> |
543 | seconds, and then every C<$repeat> seconds. The timer does his best not |
608 | seconds, and then every C<$repeat> seconds. The timer does his best not |
544 | to drift, but it will not invoke the timer more often then once per event |
609 | to drift, but it will not invoke the timer more often then once per event |
545 | loop iteration, and might drift in other cases. If that isn't acceptable, |
610 | loop iteration, and might drift in other cases. If that isn't acceptable, |
… | |
… | |
549 | in front of the machine while the timer is running and changes the system |
614 | in front of the machine while the timer is running and changes the system |
550 | clock, the timer will nevertheless run (roughly) the same time. |
615 | clock, the timer will nevertheless run (roughly) the same time. |
551 | |
616 | |
552 | The C<timer_ns> variant doesn't start (activate) the newly created watcher. |
617 | The C<timer_ns> variant doesn't start (activate) the newly created watcher. |
553 | |
618 | |
554 | =item $w->set ($after, $repeat) |
619 | =item $w->set ($after, $repeat = 0) |
555 | |
620 | |
556 | Reconfigures the watcher, see the constructor above for details. Can be called at |
621 | Reconfigures the watcher, see the constructor above for details. Can be called at |
557 | any time. |
622 | any time. |
558 | |
623 | |
559 | =item $w->again |
624 | =item $w->again |
|
|
625 | |
|
|
626 | =item $w->again ($repeat) |
560 | |
627 | |
561 | Similar to the C<start> method, but has special semantics for repeating timers: |
628 | Similar to the C<start> method, but has special semantics for repeating timers: |
562 | |
629 | |
563 | If the timer is active and non-repeating, it will be stopped. |
630 | If the timer is active and non-repeating, it will be stopped. |
564 | |
631 | |
… | |
… | |
571 | |
638 | |
572 | This behaviour is useful when you have a timeout for some IO |
639 | This behaviour is useful when you have a timeout for some IO |
573 | operation. You create a timer object with the same value for C<$after> and |
640 | operation. You create a timer object with the same value for C<$after> and |
574 | C<$repeat>, and then, in the read/write watcher, run the C<again> method |
641 | C<$repeat>, and then, in the read/write watcher, run the C<again> method |
575 | on the timeout. |
642 | on the timeout. |
|
|
643 | |
|
|
644 | If called with a C<$repeat> argument, then it uses this a timer repeat |
|
|
645 | value. |
|
|
646 | |
|
|
647 | =item $after = $w->remaining |
|
|
648 | |
|
|
649 | Calculates 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 | |
|
|
655 | Returns the current value of the repeat attribute and optionally sets a |
|
|
656 | new one. Setting the new one will not restart the watcher - if the watcher |
|
|
657 | is active, the new repeat value is used whenever it expires next. |
576 | |
658 | |
577 | =back |
659 | =back |
578 | |
660 | |
579 | |
661 | |
580 | =head3 PERIODIC WATCHERS - to cron or not to cron? |
662 | =head3 PERIODIC WATCHERS - to cron or not to cron? |
… | |
… | |
608 | surpasses this time. |
690 | surpasses this time. |
609 | |
691 | |
610 | =item * repeating interval timer ($interval > 0, $reschedule_cb = 0) |
692 | =item * repeating interval timer ($interval > 0, $reschedule_cb = 0) |
611 | |
693 | |
612 | In this mode the watcher will always be scheduled to time out at the |
694 | In this mode the watcher will always be scheduled to time out at the |
613 | next C<$at + N * $interval> time (for some integer N) and then repeat, |
695 | next C<$at + N * $interval> time (for the lowest integer N) and then repeat, |
614 | regardless of any time jumps. |
696 | regardless of any time jumps. Note that, since C<N> can be negative, the |
|
|
697 | first trigger can happen before C<$at>. |
615 | |
698 | |
616 | This can be used to create timers that do not drift with respect to system |
699 | This can be used to create timers that do not drift with respect to system |
617 | time: |
700 | time: |
618 | |
701 | |
619 | my $hourly = EV::periodic 0, 3600, 0, sub { print "once/hour\n" }; |
702 | my $hourly = EV::periodic 0, 3600, 0, sub { print "once/hour\n" }; |
620 | |
703 | |
621 | That doesn't mean there will always be 3600 seconds in between triggers, |
704 | That doesn't mean there will always be 3600 seconds in between triggers, |
622 | but only that the the clalback will be called when the system time shows a |
705 | but only that the the callback will be called when the system time shows a |
623 | full hour (UTC). |
706 | full hour (UTC). |
624 | |
707 | |
625 | Another way to think about it (for the mathematically inclined) is that |
708 | Another way to think about it (for the mathematically inclined) is that |
626 | EV::periodic will try to run the callback in this mode at the next |
709 | EV::periodic will try to run the callback in this mode at the next |
627 | possible time where C<$time = $at (mod $interval)>, regardless of any time |
710 | possible time where C<$time = $at (mod $interval)>, regardless of any time |
… | |
… | |
635 | time as second argument. |
718 | time as second argument. |
636 | |
719 | |
637 | I<This callback MUST NOT stop or destroy this or any other periodic |
720 | I<This callback MUST NOT stop or destroy this or any other periodic |
638 | watcher, ever, and MUST NOT call any event loop functions or methods>. If |
721 | watcher, ever, and MUST NOT call any event loop functions or methods>. If |
639 | you need to stop it, return 1e30 and stop it afterwards. You may create |
722 | you need to stop it, return 1e30 and stop it afterwards. You may create |
640 | and start a C<EV::prepare> watcher for this task. |
723 | and start an C<EV::prepare> watcher for this task. |
641 | |
724 | |
642 | It must return the next time to trigger, based on the passed time value |
725 | It must return the next time to trigger, based on the passed time value |
643 | (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 |
644 | argument). It will usually be called just before the callback will be |
727 | argument). It will usually be called just before the callback will be |
645 | triggered, but might be called at other times, too. |
728 | triggered, but might be called at other times, too. |
646 | |
729 | |
647 | This can be used to create very complex timers, such as a timer that |
730 | This can be used to create very complex timers, such as a timer that |
648 | triggers on each midnight, local time (actually 24 hours after the last |
731 | triggers on each midnight, local time (actually one day after the last |
649 | midnight, to keep the example simple. If you know a way to do it correctly |
732 | midnight, to keep the example simple): |
650 | in about the same space (without requiring elaborate modules), drop me a |
|
|
651 | note :): |
|
|
652 | |
733 | |
653 | my $daily = EV::periodic 0, 0, sub { |
734 | my $daily = EV::periodic 0, 0, sub { |
654 | my ($w, $now) = @_; |
735 | my ($w, $now) = @_; |
655 | |
736 | |
656 | use Time::Local (); |
737 | use Time::Local (); |
657 | my (undef, undef, undef, $d, $m, $y) = localtime $now; |
738 | my (undef, undef, undef, $d, $m, $y) = localtime $now; |
658 | 86400 + Time::Local::timelocal 0, 0, 0, $d, $m, $y |
739 | Time::Local::timelocal_nocheck 0, 0, 0, $d + 1, $m, $y |
659 | }, sub { |
740 | }, sub { |
660 | print "it's midnight or likely shortly after, now\n"; |
741 | print "it's midnight or likely shortly after, now\n"; |
661 | }; |
742 | }; |
662 | |
743 | |
663 | =back |
744 | =back |
… | |
… | |
675 | |
756 | |
676 | =item $time = $w->at |
757 | =item $time = $w->at |
677 | |
758 | |
678 | Return the time that the watcher is expected to trigger next. |
759 | Return the time that the watcher is expected to trigger next. |
679 | |
760 | |
|
|
761 | =item $offset = $w->offset |
|
|
762 | |
|
|
763 | =item $old_offset = $w->offset ($new_offset) |
|
|
764 | |
|
|
765 | Returns the current value of the offset attribute and optionally sets a |
|
|
766 | new one. Setting the new one will not restart the watcher - if the watcher |
|
|
767 | is 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 | |
|
|
773 | See 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 | |
|
|
779 | See above, for the reschedule callback. |
|
|
780 | |
680 | =back |
781 | =back |
681 | |
782 | |
682 | |
783 | |
683 | =head3 SIGNAL WATCHERS - signal me when a signal gets signalled! |
784 | =head3 SIGNAL WATCHERS - signal me when a signal gets signalled! |
684 | |
785 | |
685 | =over 4 |
786 | =over 4 |
686 | |
787 | |
687 | =item $w = EV::signal $signal, $callback |
788 | =item $w = EV::signal $signal, $callback |
688 | |
789 | |
689 | =item $w = EV::signal_ns $signal, $callback |
790 | =item $w = EV::signal_ns $signal, $callback |
|
|
791 | |
|
|
792 | =item $w = $loop->signal ($signal, $callback) |
|
|
793 | |
|
|
794 | =item $w = $loop->signal_ns ($signal, $callback) |
690 | |
795 | |
691 | Call the callback when $signal is received (the signal can be specified by |
796 | Call the callback when $signal is received (the signal can be specified by |
692 | number or by name, just as with C<kill> or C<%SIG>). |
797 | number or by name, just as with C<kill> or C<%SIG>). |
|
|
798 | |
|
|
799 | Only one event loop can grab a given signal - attempting to grab the same |
|
|
800 | signal from two EV loops will crash the program immediately or cause data |
|
|
801 | corruption. |
693 | |
802 | |
694 | EV will grab the signal for the process (the kernel only allows one |
803 | EV will grab the signal for the process (the kernel only allows one |
695 | component to receive a signal at a time) when you start a signal watcher, |
804 | component to receive a signal at a time) when you start a signal watcher, |
696 | and removes it again when you stop it. Perl does the same when you |
805 | and removes it again when you stop it. Perl does the same when you |
697 | add/remove callbacks to C<%SIG>, so watch out. |
806 | add/remove callbacks to C<%SIG>, so watch out. |
… | |
… | |
922 | =item $w = $loop->check_ns ($callback) |
1031 | =item $w = $loop->check_ns ($callback) |
923 | |
1032 | |
924 | Call the callback just after the process wakes up again (after it has |
1033 | Call the callback just after the process wakes up again (after it has |
925 | gathered events), but before any other callbacks have been invoked. |
1034 | gathered events), but before any other callbacks have been invoked. |
926 | |
1035 | |
927 | This is used to integrate other event-based software into the EV |
1036 | This can be used to integrate other event-based software into the EV |
928 | mainloop: You register a prepare callback and in there, you create io and |
1037 | mainloop: You register a prepare callback and in there, you create io and |
929 | timer watchers as required by the other software. Here is a real-world |
1038 | timer watchers as required by the other software. Here is a real-world |
930 | example of integrating Net::SNMP (with some details left out): |
1039 | example of integrating Net::SNMP (with some details left out): |
931 | |
1040 | |
932 | our @snmp_watcher; |
1041 | our @snmp_watcher; |
… | |
… | |
966 | The callbacks of the created watchers will not be called as the watchers |
1075 | The callbacks of the created watchers will not be called as the watchers |
967 | are destroyed before this can happen (remember EV::check gets called |
1076 | are destroyed before this can happen (remember EV::check gets called |
968 | first). |
1077 | first). |
969 | |
1078 | |
970 | The C<check_ns> variant doesn't start (activate) the newly created watcher. |
1079 | The C<check_ns> variant doesn't start (activate) the newly created watcher. |
|
|
1080 | |
|
|
1081 | =item EV::CHECK constant issues |
|
|
1082 | |
|
|
1083 | Like all other watcher types, there is a bitmask constant for use in |
|
|
1084 | C<$revents> and other places. The C<EV::CHECK> is special as it has |
|
|
1085 | the same name as the C<CHECK> sub called by Perl. This doesn't cause |
|
|
1086 | big issues on newer perls (beginning with 5.8.9), but it means thatthe |
|
|
1087 | constant must be I<inlined>, i.e. runtime calls will not work. That means |
|
|
1088 | that as long as you always C<use EV> and then C<EV::CHECK> you are on the |
|
|
1089 | safe side. |
971 | |
1090 | |
972 | =back |
1091 | =back |
973 | |
1092 | |
974 | |
1093 | |
975 | =head3 FORK WATCHERS - the audacity to resume the event loop after a fork |
1094 | =head3 FORK WATCHERS - the audacity to resume the event loop after a fork |
… | |
… | |
1057 | |
1176 | |
1058 | =item $w = EV::async $callback |
1177 | =item $w = EV::async $callback |
1059 | |
1178 | |
1060 | =item $w = EV::async_ns $callback |
1179 | =item $w = EV::async_ns $callback |
1061 | |
1180 | |
|
|
1181 | =item $w = $loop->async ($callback) |
|
|
1182 | |
|
|
1183 | =item $w = $loop->async_ns ($callback) |
|
|
1184 | |
1062 | =item $w->send |
1185 | =item $w->send |
1063 | |
1186 | |
1064 | =item $bool = $w->async_pending |
1187 | =item $bool = $w->async_pending |
1065 | |
1188 | |
1066 | =back |
1189 | =back |
|
|
1190 | |
|
|
1191 | =head3 CLEANUP WATCHERS - how to clean up when the event loop goes away |
|
|
1192 | |
|
|
1193 | Cleanup watchers are not supported on the Perl level, they can only be |
|
|
1194 | used via XS currently. |
1067 | |
1195 | |
1068 | |
1196 | |
1069 | =head1 PERL SIGNALS |
1197 | =head1 PERL SIGNALS |
1070 | |
1198 | |
1071 | While Perl signal handling (C<%SIG>) is not affected by EV, the behaviour |
1199 | While Perl signal handling (C<%SIG>) is not affected by EV, the behaviour |
… | |
… | |
1119 | |
1247 | |
1120 | 1; |
1248 | 1; |
1121 | |
1249 | |
1122 | =head1 SEE ALSO |
1250 | =head1 SEE ALSO |
1123 | |
1251 | |
|
|
1252 | L<EV::MakeMaker> - MakeMaker interface to XS API, L<EV::ADNS> |
1124 | L<EV::ADNS> (asynchronous DNS), L<Glib::EV> (makes Glib/Gtk2 use EV as |
1253 | (asynchronous DNS), L<Glib::EV> (makes Glib/Gtk2 use EV as event |
1125 | event loop), L<EV::Glib> (embed Glib into EV), L<Coro::EV> (efficient |
1254 | loop), L<EV::Glib> (embed Glib into EV), L<Coro::EV> (efficient thread |
1126 | coroutines with EV), L<Net::SNMP::EV> (asynchronous SNMP), L<AnyEvent> for |
1255 | integration), L<Net::SNMP::EV> (asynchronous SNMP), L<AnyEvent> for |
1127 | event-loop agnostic and portable event driven programming. |
1256 | event-loop agnostic and portable event driven programming. |
1128 | |
1257 | |
1129 | =head1 AUTHOR |
1258 | =head1 AUTHOR |
1130 | |
1259 | |
1131 | Marc Lehmann <schmorp@schmorp.de> |
1260 | Marc Lehmann <schmorp@schmorp.de> |