[ViewVC] Diff of: cvs/EV/EV.pm

Comparing EV/EV.pm (file contents):
Revision 1.45 by root, Fri Nov 23 03:59:23 2007 UTC vs.
Revision 1.71 by root, Mon Dec 17 07:24:12 2007 UTC

…		…
39		39
40	my $w = EV::child 666, sub {	40	my $w = EV::child 666, sub {
41	my ($w, $revents) = @_;	41	my ($w, $revents) = @_;
42	my $status = $w->rstatus;	42	my $status = $w->rstatus;
43	};	43	};
		44
		45	# STAT CHANGES
		46	my $w = EV::stat "/etc/passwd", 10, sub {
		47	my ($w, $revents) = @_;
		48	warn $w->path, " has changed somehow.\n";
		49	};
44		50
45	# MAINLOOP	51	# MAINLOOP
46	EV::loop; # loop until EV::unloop is called or all watchers stop	52	EV::loop; # loop until EV::unloop is called or all watchers stop
47	EV::loop EV::LOOP_ONESHOT; # block until at least one event could be handled	53	EV::loop EV::LOOP_ONESHOT; # block until at least one event could be handled
48	EV::loop EV::LOOP_NONBLOCK; # try to handle same events, but do not block	54	EV::loop EV::LOOP_NONBLOCK; # try to handle same events, but do not block
49		55
50	=head1 DESCRIPTION	56	=head1 DESCRIPTION
51		57
52	This module provides an interface to libev	58	This module provides an interface to libev
53	(L<http://software.schmorp.de/pkg/libev.html>).	59	(L<http://software.schmorp.de/pkg/libev.html>). While the documentation
		60	below is comprehensive, one might also consult the documentation of libev
		61	itself (L<http://cvs.schmorp.de/libev/ev.html>) for more subtle details on
		62	watcher semantics or some discussion on the available backends, or how to
		63	force a specific backend with C<LIBEV_FLAGS>, or just about in any case
		64	because it has much more detailed information.
54		65
55	=cut	66	=cut
56		67
57	package EV;	68	package EV;
58		69
59	use strict;	70	use strict;
60		71
61	BEGIN {	72	BEGIN {
62	our $VERSION = '1.2';	73	our $VERSION = '1.86';
63	use XSLoader;	74	use XSLoader;
64	XSLoader::load "EV", $VERSION;	75	XSLoader::load "EV", $VERSION;
65	}	76	}
66		77
67	@EV::Io::ISA =	78	@EV::IO::ISA =
68	@EV::Timer::ISA =	79	@EV::Timer::ISA =
69	@EV::Periodic::ISA =	80	@EV::Periodic::ISA =
70	@EV::Signal::ISA =	81	@EV::Signal::ISA =
		82	@EV::Child::ISA =
		83	@EV::Stat::ISA =
71	@EV::Idle::ISA =	84	@EV::Idle::ISA =
72	@EV::Prepare::ISA =	85	@EV::Prepare::ISA =
73	@EV::Check::ISA =	86	@EV::Check::ISA =
74	@EV::Child::ISA = "EV::Watcher";	87	@EV::Embed::ISA =
		88	@EV::Fork::ISA =
		89	"EV::Watcher";
75		90
76	=head1 BASIC INTERFACE	91	=head1 BASIC INTERFACE
77		92
78	=over 4	93	=over 4
79		94
80	=item $EV::DIED	95	=item $EV::DIED
81		96
82	Must contain a reference to a function that is called when a callback	97	Must contain a reference to a function that is called when a callback
83	throws an exception (with $@ containing thr error). The default prints an	98	throws an exception (with $@ containing the error). The default prints an
84	informative message and continues.	99	informative message and continues.
85		100
86	If this callback throws an exception it will be silently ignored.	101	If this callback throws an exception it will be silently ignored.
87		102
88	=item $time = EV::time	103	=item $time = EV::time
…		…
117	innermost call to EV::loop return.	132	innermost call to EV::loop return.
118		133
119	When called with an argument of EV::UNLOOP_ALL, all calls to EV::loop will return as	134	When called with an argument of EV::UNLOOP_ALL, all calls to EV::loop will return as
120	fast as possible.	135	fast as possible.
121		136
122	=back	137	=item $count = EV::loop_count
123		138
		139	Return the number of times the event loop has polled for new
		140	events. Sometiems useful as a generation counter.
		141
		142	=item EV::once $fh_or_undef, $events, $timeout, $cb->($revents)
		143
		144	This function rolls together an I/O and a timer watcher for a single
		145	one-shot event without the need for managing a watcher object.
		146
		147	If C<$fh_or_undef> is a filehandle or file descriptor, then C<$events>
		148	must be a bitset containing either C<EV::READ>, C<EV::WRITE> or C<EV::READ
		149	\| EV::WRITE>, indicating the type of I/O event you want to wait for. If
		150	you do not want to wait for some I/O event, specify C<undef> for
		151	C<$fh_or_undef> and C<0> for C<$events>).
		152
		153	If timeout is C<undef> or negative, then there will be no
		154	timeout. Otherwise a EV::timer with this value will be started.
		155
		156	When an error occurs or either the timeout or I/O watcher triggers, then
		157	the callback will be called with the received event set (in general
		158	you can expect it to be a combination of C<EV:ERROR>, C<EV::READ>,
		159	C<EV::WRITE> and C<EV::TIMEOUT>).
		160
		161	EV::once doesn't return anything: the watchers stay active till either
		162	of them triggers, then they will be stopped and freed, and the callback
		163	invoked.
		164
		165	=item EV::feed_fd_event ($fd, $revents)
		166
		167	Feed an event on a file descriptor into EV. EV will react to this call as
		168	if the readyness notifications specified by C<$revents> (a combination of
		169	C<EV::READ> and C<EV::WRITE>) happened on the file descriptor C<$fd>.
		170
		171	=item EV::feed_signal_event ($signal)
		172
		173	Feed a signal event into EV. EV will react to this call as if the signal
		174	specified by C<$signal> had occured.
		175
		176	=back
		177
		178
124	=head2 WATCHER	179	=head2 WATCHER OBJECTS
125		180
126	A watcher is an object that gets created to record your interest in some	181	A watcher is an object that gets created to record your interest in some
127	event. For instance, if you want to wait for STDIN to become readable, you	182	event. For instance, if you want to wait for STDIN to become readable, you
128	would create an EV::io watcher for that:	183	would create an EV::io watcher for that:
129		184
…		…
138	events.	193	events.
139		194
140	Each watcher type has its associated bit in revents, so you can use the	195	Each watcher type has its associated bit in revents, so you can use the
141	same callback for multiple watchers. The event mask is named after the	196	same callback for multiple watchers. The event mask is named after the
142	type, i..e. EV::child sets EV::CHILD, EV::prepare sets EV::PREPARE,	197	type, i..e. EV::child sets EV::CHILD, EV::prepare sets EV::PREPARE,
143	EV::periodic sets EV::PERIODIC and so on, with the exception of IO events	198	EV::periodic sets EV::PERIODIC and so on, with the exception of I/O events
144	(which can set both EV::READ and EV::WRITE bits), and EV::timer (which	199	(which can set both EV::READ and EV::WRITE bits), and EV::timer (which
145	uses EV::TIMEOUT).	200	uses EV::TIMEOUT).
146		201
147	In the rare case where one wants to create a watcher but not start it at	202	In the rare case where one wants to create a watcher but not start it at
148	the same time, each constructor has a variant with a trailing C<_ns> in	203	the same time, each constructor has a variant with a trailing C<_ns> in
…		…
154		209
155	Also, all methods changing some aspect of a watcher (->set, ->priority,	210	Also, all methods changing some aspect of a watcher (->set, ->priority,
156	->fh and so on) automatically stop and start it again if it is active,	211	->fh and so on) automatically stop and start it again if it is active,
157	which means pending events get lost.	212	which means pending events get lost.
158		213
159	=head2 WATCHER TYPES	214	=head2 COMMON WATCHER METHODS
160		215
161	Now lets move to the existing watcher types and asociated methods.	216	This section lists methods common to all watchers.
162
163	The following methods are available for all watchers. Then followes a
164	description of each watcher constructor (EV::io, EV::timer, EV::periodic,
165	EV::signal, EV::child, EV::idle, EV::prepare and EV::check), followed by
166	any type-specific methods (if any).
167		217
168	=over 4	218	=over 4
169		219
170	=item $w->start	220	=item $w->start
171		221
…		…
175		225
176	=item $w->stop	226	=item $w->stop
177		227
178	Stop a watcher if it is active. Also clear any pending events (events that	228	Stop a watcher if it is active. Also clear any pending events (events that
179	have been received but that didn't yet result in a callback invocation),	229	have been received but that didn't yet result in a callback invocation),
180	regardless of wether the watcher was active or not.	230	regardless of whether the watcher was active or not.
181		231
182	=item $bool = $w->is_active	232	=item $bool = $w->is_active
183		233
184	Returns true if the watcher is active, false otherwise.	234	Returns true if the watcher is active, false otherwise.
185		235
…		…
210	watchers with higher priority will be invoked first. The valid range of	260	watchers with higher priority will be invoked first. The valid range of
211	priorities lies between EV::MAXPRI (default 2) and EV::MINPRI (default	261	priorities lies between EV::MAXPRI (default 2) and EV::MINPRI (default
212	-2). If the priority is outside this range it will automatically be	262	-2). If the priority is outside this range it will automatically be
213	normalised to the nearest valid priority.	263	normalised to the nearest valid priority.
214		264
215	The default priority of any newly-created weatcher is 0.	265	The default priority of any newly-created watcher is 0.
216		266
		267	Note that the priority semantics have not yet been fleshed out and are
		268	subject to almost certain change.
		269
217	=item $w->trigger ($revents)	270	=item $w->invoke ($revents)
218		271
219	Call the callback now with the given event mask.	272	Call the callback now with the given event mask.
220		273
		274	=item $w->feed_event ($revents)
		275
		276	Feed some events on this watcher into EV. EV will react to this call as if
		277	the watcher had received the given C<$revents> mask.
		278
		279	=item $revents = $w->clear_pending
		280
		281	If the watcher is pending, this function returns clears its pending status
		282	and returns its C<$revents> bitset (as if its callback was invoked). If the
		283	watcher isn't pending it does nothing and returns C<0>.
		284
		285	=item $previous_state = $w->keepalive ($bool)
		286
		287	Normally, C<EV::loop> will return when there are no active watchers
		288	(which is a "deadlock" because no progress can be made anymore). This is
		289	convinient because it allows you to start your watchers (and your jobs),
		290	call C<EV::loop> once and when it returns you know that all your jobs are
		291	finished (or they forgot to register some watchers for their task :).
		292
		293	Sometimes, however, this gets in your way, for example when you the module
		294	that calls C<EV::loop> (usually the main program) is not the same module
		295	as a long-living watcher (for example a DNS client module written by
		296	somebody else even). Then you might want any outstanding requests to be
		297	handled, but you would not want to keep C<EV::loop> from returning just
		298	because you happen to have this long-running UDP port watcher.
		299
		300	In this case you can clear the keepalive status, which means that even
		301	though your watcher is active, it won't keep C<EV::loop> from returning.
		302
		303	The initial value for keepalive is true (enabled), and you cna change it
		304	any time.
		305
		306	Example: Register an I/O watcher for some UDP socket but do not keep the
		307	event loop from running just because of that watcher.
		308
		309	my $udp_socket = ...
		310	my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... };
		311	$udp_watcher->keepalive (0);
		312
		313	=back
		314
		315
		316	=head2 WATCHER TYPES
		317
		318	Each of the following subsections describes a single watcher type.
		319
		320	=head3 I/O WATCHERS - is this file descriptor readable or writable?
		321
		322	=over 4
221		323
222	=item $w = EV::io $fileno_or_fh, $eventmask, $callback	324	=item $w = EV::io $fileno_or_fh, $eventmask, $callback
223		325
224	=item $w = EV::io_ns $fileno_or_fh, $eventmask, $callback	326	=item $w = EV::io_ns $fileno_or_fh, $eventmask, $callback
225		327
226	As long as the returned watcher object is alive, call the C<$callback>	328	As long as the returned watcher object is alive, call the C<$callback>
227	when the events specified in C<$eventmask>.	329	when at least one of events specified in C<$eventmask> occurs.
228		330
229	The $eventmask can be one or more of these constants ORed together:	331	The $eventmask can be one or more of these constants ORed together:
230		332
231	EV::READ wait until read() wouldn't block anymore	333	EV::READ wait until read() wouldn't block anymore
232	EV::WRITE wait until write() wouldn't block anymore	334	EV::WRITE wait until write() wouldn't block anymore
…		…
248		350
249	=item $old_eventmask = $w->events ($new_eventmask)	351	=item $old_eventmask = $w->events ($new_eventmask)
250		352
251	Returns the previously set event mask and optionally set a new one.	353	Returns the previously set event mask and optionally set a new one.
252		354
		355	=back
		356
		357
		358	=head3 TIMER WATCHERS - relative and optionally repeating timeouts
		359
		360	=over 4
253		361
254	=item $w = EV::timer $after, $repeat, $callback	362	=item $w = EV::timer $after, $repeat, $callback
255		363
256	=item $w = EV::timer_ns $after, $repeat, $callback	364	=item $w = EV::timer_ns $after, $repeat, $callback
257		365
258	Calls the callback after C<$after> seconds. If C<$repeat> is non-zero,	366	Calls the callback after C<$after> seconds (which may be fractional). If
259	the timer will be restarted (with the $repeat value as $after) after the	367	C<$repeat> is non-zero, the timer will be restarted (with the $repeat
260	callback returns.	368	value as $after) after the callback returns.
261		369
262	This means that the callback would be called roughly after C<$after>	370	This means that the callback would be called roughly after C<$after>
263	seconds, and then every C<$repeat> seconds. The timer does his best not	371	seconds, and then every C<$repeat> seconds. The timer does his best not
264	to drift, but it will not invoke the timer more often then once per event	372	to drift, but it will not invoke the timer more often then once per event
265	loop iteration, and might drift in other cases. If that isn't acceptable,	373	loop iteration, and might drift in other cases. If that isn't acceptable,
…		…
271		379
272	The C<timer_ns> variant doesn't start (activate) the newly created watcher.	380	The C<timer_ns> variant doesn't start (activate) the newly created watcher.
273		381
274	=item $w->set ($after, $repeat)	382	=item $w->set ($after, $repeat)
275		383
276	Reconfigures the watcher, see the constructor above for details. Can be at	384	Reconfigures the watcher, see the constructor above for details. Can be called at
277	any time.	385	any time.
278		386
279	=item $w->again	387	=item $w->again
280		388
281	Similar to the C<start> method, but has special semantics for repeating timers:	389	Similar to the C<start> method, but has special semantics for repeating timers:
…		…
292	This behaviour is useful when you have a timeout for some IO	400	This behaviour is useful when you have a timeout for some IO
293	operation. You create a timer object with the same value for C<$after> and	401	operation. You create a timer object with the same value for C<$after> and
294	C<$repeat>, and then, in the read/write watcher, run the C<again> method	402	C<$repeat>, and then, in the read/write watcher, run the C<again> method
295	on the timeout.	403	on the timeout.
296		404
		405	=back
		406
		407
		408	=head3 PERIODIC WATCHERS - to cron or not to cron?
		409
		410	=over 4
297		411
298	=item $w = EV::periodic $at, $interval, $reschedule_cb, $callback	412	=item $w = EV::periodic $at, $interval, $reschedule_cb, $callback
299		413
300	=item $w = EV::periodic_ns $at, $interval, $reschedule_cb, $callback	414	=item $w = EV::periodic_ns $at, $interval, $reschedule_cb, $callback
301		415
…		…
373		487
374	The C<periodic_ns> variant doesn't start (activate) the newly created watcher.	488	The C<periodic_ns> variant doesn't start (activate) the newly created watcher.
375		489
376	=item $w->set ($at, $interval, $reschedule_cb)	490	=item $w->set ($at, $interval, $reschedule_cb)
377		491
378	Reconfigures the watcher, see the constructor above for details. Can be at	492	Reconfigures the watcher, see the constructor above for details. Can be called at
379	any time.	493	any time.
380		494
381	=item $w->again	495	=item $w->again
382		496
383	Simply stops and starts the watcher again.	497	Simply stops and starts the watcher again.
384		498
		499	=item $time = $w->at
		500
		501	Return the time that the watcher is expected to trigger next.
		502
		503	=back
		504
		505
		506	=head3 SIGNAL WATCHERS - signal me when a signal gets signalled!
		507
		508	=over 4
385		509
386	=item $w = EV::signal $signal, $callback	510	=item $w = EV::signal $signal, $callback
387		511
388	=item $w = EV::signal_ns $signal, $callback	512	=item $w = EV::signal_ns $signal, $callback
389		513
390	Call the callback when $signal is received (the signal can be specified	514	Call the callback when $signal is received (the signal can be specified by
391	by number or by name, just as with kill or %SIG).	515	number or by name, just as with C<kill> or C<%SIG>).
392		516
393	EV will grab the signal for the process (the kernel only allows one	517	EV will grab the signal for the process (the kernel only allows one
394	component to receive a signal at a time) when you start a signal watcher,	518	component to receive a signal at a time) when you start a signal watcher,
395	and removes it again when you stop it. Perl does the same when you	519	and removes it again when you stop it. Perl does the same when you
396	add/remove callbacks to %SIG, so watch out.	520	add/remove callbacks to C<%SIG>, so watch out.
397		521
398	You can have as many signal watchers per signal as you want.	522	You can have as many signal watchers per signal as you want.
399		523
400	The C<signal_ns> variant doesn't start (activate) the newly created watcher.	524	The C<signal_ns> variant doesn't start (activate) the newly created watcher.
401		525
402	=item $w->set ($signal)	526	=item $w->set ($signal)
403		527
404	Reconfigures the watcher, see the constructor above for details. Can be at	528	Reconfigures the watcher, see the constructor above for details. Can be
405	any time.	529	called at any time.
406		530
407	=item $current_signum = $w->signal	531	=item $current_signum = $w->signal
408		532
409	=item $old_signum = $w->signal ($new_signal)	533	=item $old_signum = $w->signal ($new_signal)
410		534
411	Returns the previously set signal (always as a number not name) and	535	Returns the previously set signal (always as a number not name) and
412	optionally set a new one.	536	optionally set a new one.
413		537
		538	=back
		539
		540
		541	=head3 CHILD WATCHERS - watch out for process status changes
		542
		543	=over 4
414		544
415	=item $w = EV::child $pid, $callback	545	=item $w = EV::child $pid, $callback
416		546
417	=item $w = EV::child_ns $pid, $callback	547	=item $w = EV::child_ns $pid, $callback
418		548
419	Call the callback when a status change for pid C<$pid> (or any pid	549	Call the callback when a status change for pid C<$pid> (or any pid if
420	if C<$pid> is 0) has been received. More precisely: when the process	550	C<$pid> is 0) has been received. More precisely: when the process receives
421	receives a SIGCHLD, EV will fetch the outstanding exit/wait status for all	551	a C<SIGCHLD>, EV will fetch the outstanding exit/wait status for all
422	changed/zombie children and call the callback.	552	changed/zombie children and call the callback.
423		553
424	You can access both status and pid by using the C<rstatus> and C<rpid>	554	It is valid (and fully supported) to install a child watcher after a child
425	methods on the watcher object.	555	has exited but before the event loop has started its next iteration (for
		556	example, first you C<fork>, then the new child process might exit, and
		557	only then do you install a child watcher in the parent for the new pid).
426		558
		559	You can access both exit (or tracing) status and pid by using the
		560	C<rstatus> and C<rpid> methods on the watcher object.
		561
427	You can have as many pid watchers per pid as you want.	562	You can have as many pid watchers per pid as you want, they will all be
		563	called.
428		564
429	The C<child_ns> variant doesn't start (activate) the newly created watcher.	565	The C<child_ns> variant doesn't start (activate) the newly created watcher.
430		566
431	=item $w->set ($pid)	567	=item $w->set ($pid)
432		568
433	Reconfigures the watcher, see the constructor above for details. Can be at	569	Reconfigures the watcher, see the constructor above for details. Can be called at
434	any time.	570	any time.
435		571
436	=item $current_pid = $w->pid	572	=item $current_pid = $w->pid
437		573
438	=item $old_pid = $w->pid ($new_pid)	574	=item $old_pid = $w->pid ($new_pid)
…		…
447	=item $pid = $w->rpid	583	=item $pid = $w->rpid
448		584
449	Return the pid of the awaited child (useful when you have installed a	585	Return the pid of the awaited child (useful when you have installed a
450	watcher for all pids).	586	watcher for all pids).
451		587
		588	=back
		589
		590
		591	=head3 STAT WATCHERS - did the file attributes just change?
		592
		593	=over 4
		594
		595	=item $w = EV::stat $path, $interval, $callback
		596
		597	=item $w = EV::stat_ns $path, $interval, $callback
		598
		599	Call the callback when a file status change has been detected on
		600	C<$path>. The C<$path> does not need to exist, changing from "path exists"
		601	to "path does not exist" is a status change like any other.
		602
		603	The C<$interval> is a recommended polling interval for systems where
		604	OS-supported change notifications don't exist or are not supported. If
		605	you use C<0> then an unspecified default is used (which is highly
		606	recommended!), which is to be expected to be around five seconds usually.
		607
		608	This watcher type is not meant for massive numbers of stat watchers,
		609	as even with OS-supported change notifications, this can be
		610	resource-intensive.
		611
		612	The C<stat_ns> variant doesn't start (activate) the newly created watcher.
		613
		614	=item ... = $w->stat
		615
		616	This call is very similar to the perl C<stat> built-in: It stats (using
		617	C<lstat>) the path specified in the watcher and sets perls stat cache (as
		618	well as EV's idea of the current stat values) to the values found.
		619
		620	In scalar context, a boolean is return indicating success or failure of
		621	the stat. In list context, the same 13-value list as with stat is returned
		622	(except that the blksize and blocks fields are not reliable).
		623
		624	In the case of an error, errno is set to C<ENOENT> (regardless of the
		625	actual error value) and the C<nlink> value is forced to zero (if the stat
		626	was successful then nlink is guaranteed to be non-zero).
		627
		628	See also the next two entries for more info.
		629
		630	=item ... = $w->attr
		631
		632	Just like C<< $w->stat >>, but without the initial stat'ing: this returns
		633	the values most recently detected by EV. See the next entry for more info.
		634
		635	=item ... = $w->prev
		636
		637	Just like C<< $w->stat >>, but without the initial stat'ing: this returns
		638	the previous set of values, before the change.
		639
		640	That is, when the watcher callback is invoked, C<< $w->prev >> will be set
		641	to the values found I<before> a change was detected, while C<< $w->attr >>
		642	returns the values found leading to the change detection. The difference (if any)
		643	between C<prev> and C<attr> is what triggered the callback.
		644
		645	If you did something to the filesystem object and do not want to trigger
		646	yet another change, you can call C<stat> to update EV's idea of what the
		647	current attributes are.
		648
		649	=item $w->set ($path, $interval)
		650
		651	Reconfigures the watcher, see the constructor above for details. Can be
		652	called at any time.
		653
		654	=item $current_path = $w->path
		655
		656	=item $old_path = $w->path ($new_path)
		657
		658	Returns the previously set path and optionally set a new one.
		659
		660	=item $current_interval = $w->interval
		661
		662	=item $old_interval = $w->interval ($new_interval)
		663
		664	Returns the previously set interval and optionally set a new one. Can be
		665	used to query the actual interval used.
		666
		667	=back
		668
		669
		670	=head3 IDLE WATCHERS - when you've got nothing better to do...
		671
		672	=over 4
452		673
453	=item $w = EV::idle $callback	674	=item $w = EV::idle $callback
454		675
455	=item $w = EV::idle_ns $callback	676	=item $w = EV::idle_ns $callback
456		677
457	Call the callback when there are no pending io, timer/periodic, signal or	678	Call the callback when there are no other pending watchers of the same or
458	child events, i.e. when the process is idle.	679	higher priority (excluding check, prepare and other idle watchers of the
		680	same or lower priority, of course). They are called idle watchers because
		681	when the watcher is the highest priority pending event in the process, the
		682	process is considered to be idle at that priority.
		683
		684	If you want a watcher that is only ever called when I<no> other events are
		685	outstanding you have to set the priority to C<EV::MINPRI>.
459		686
460	The process will not block as long as any idle watchers are active, and	687	The process will not block as long as any idle watchers are active, and
461	they will be called repeatedly until stopped.	688	they will be called repeatedly until stopped.
462		689
		690	For example, if you have idle watchers at priority C<0> and C<1>, and
		691	an I/O watcher at priority C<0>, then the idle watcher at priority C<1>
		692	and the I/O watcher will always run when ready. Only when the idle watcher
		693	at priority C<1> is stopped and the I/O watcher at priority C<0> is not
		694	pending with the C<0>-priority idle watcher be invoked.
		695
463	The C<idle_ns> variant doesn't start (activate) the newly created watcher.	696	The C<idle_ns> variant doesn't start (activate) the newly created watcher.
464		697
		698	=back
		699
		700
		701	=head3 PREPARE WATCHERS - customise your event loop!
		702
		703	=over 4
465		704
466	=item $w = EV::prepare $callback	705	=item $w = EV::prepare $callback
467		706
468	=item $w = EV::prepare_ns $callback	707	=item $w = EV::prepare_ns $callback
469		708
…		…
472		711
473	See the EV::check watcher, below, for explanations and an example.	712	See the EV::check watcher, below, for explanations and an example.
474		713
475	The C<prepare_ns> variant doesn't start (activate) the newly created watcher.	714	The C<prepare_ns> variant doesn't start (activate) the newly created watcher.
476		715
		716	=back
		717
		718
		719	=head3 CHECK WATCHERS - customise your event loop even more!
		720
		721	=over 4
477		722
478	=item $w = EV::check $callback	723	=item $w = EV::check $callback
479		724
480	=item $w = EV::check_ns $callback	725	=item $w = EV::check_ns $callback
481		726
…		…
495	or return;	740	or return;
496		741
497	# make the dispatcher handle any outstanding stuff	742	# make the dispatcher handle any outstanding stuff
498	... not shown	743	... not shown
499		744
500	# create an IO watcher for each and every socket	745	# create an I/O watcher for each and every socket
501	@snmp_watcher = (	746	@snmp_watcher = (
502	(map { EV::io $_, EV::READ, sub { } }	747	(map { EV::io $_, EV::READ, sub { } }
503	keys %{ $dispatcher->{_descriptors} }),	748	keys %{ $dispatcher->{_descriptors} }),
504		749
505	EV::timer +($event->[Net::SNMP::Dispatcher::_ACTIVE]	750	EV::timer +($event->[Net::SNMP::Dispatcher::_ACTIVE]
…		…
527		772
528	The C<check_ns> variant doesn't start (activate) the newly created watcher.	773	The C<check_ns> variant doesn't start (activate) the newly created watcher.
529		774
530	=back	775	=back
531		776
		777
		778	=head3 FORK WATCHERS - the audacity to resume the event loop after a fork
		779
		780	Fork watchers are called when a C<fork ()> was detected. The invocation
		781	is done before the event loop blocks next and before C<check> watchers
		782	are being called, and only in the child after the fork.
		783
		784	=over 4
		785
		786	=item $w = EV::fork $callback
		787
		788	=item $w = EV::fork_ns $callback
		789
		790	Call the callback before the event loop is resumed in the child process
		791	after a fork.
		792
		793	The C<fork_ns> variant doesn't start (activate) the newly created watcher.
		794
		795	=back
		796
		797
		798	=head1 PERL SIGNALS
		799
		800	While Perl signal handling (C<%SIG>) is not affected by EV, the behaviour
		801	with EV is as the same as any other C library: Perl-signals will only be
		802	handled when Perl runs, which means your signal handler might be invoked
		803	only the next time an event callback is invoked.
		804
		805	The solution is to use EV signal watchers (see C<EV::signal>), which will
		806	ensure proper operations with regards to other event watchers.
		807
		808	If you cannot do this for whatever reason, you can also force a watcher
		809	to be called on every event loop iteration by installing a C<EV::check>
		810	watcher:
		811
		812	my $async_check = EV::check sub { };
		813
		814	This ensures that perl shortly gets into control for a short time, and
		815	also ensures slower overall operation.
		816
532	=head1 THREADS	817	=head1 THREADS
533		818
534	Threads are not supported by this module in any way. Perl pseudo-threads	819	Threads are not supported by this module in any way. Perl pseudo-threads
535	is evil stuff and must die.	820	is evil stuff and must die. As soon as Perl gains real threads I will work
		821	on thread support for it.
		822
		823	=head1 FORK
		824
		825	Most of the "improved" event delivering mechanisms of modern operating
		826	systems have quite a few problems with fork(2) (to put it bluntly: it is
		827	not supported and usually destructive). Libev makes it possible to work
		828	around this by having a function that recreates the kernel state after
		829	fork in the child.
		830
		831	On non-win32 platforms, this module requires the pthread_atfork
		832	functionality to do this automatically for you. This function is quite
		833	buggy on most BSDs, though, so YMMV. The overhead for this is quite
		834	negligible, because everything the function currently does is set a flag
		835	that is checked only when the event loop gets used the next time, so when
		836	you do fork but not use EV, the overhead is minimal.
		837
		838	On win32, there is no notion of fork so all this doesn't apply, of course.
536		839
537	=cut	840	=cut
538		841
539	our $DIED = sub {	842	our $DIED = sub {
540	warn "EV: error in callback (ignoring): $@";	843	warn "EV: error in callback (ignoring): $@";
541	};	844	};
542		845
543	default_loop	846	default_loop
544	or die 'EV: cannot initialise libev backend. bad $ENV{LIBEV_METHODS}?';	847	or die 'EV: cannot initialise libev backend. bad $ENV{LIBEV_FLAGS}?';
545		848
546	1;	849	1;
547		850
548	=head1 SEE ALSO	851	=head1 SEE ALSO
549		852
550	L<EV::DNS>.	853	L<EV::ADNS> (asynchronous dns), L<Glib::EV> (makes Glib/Gtk2 use EV as
		854	event loop), L<Coro::EV> (efficient coroutines with EV).
551		855
552	=head1 AUTHOR	856	=head1 AUTHOR
553		857
554	Marc Lehmann <schmorp@schmorp.de>	858	Marc Lehmann <schmorp@schmorp.de>
555	http://home.schmorp.de/	859	http://home.schmorp.de/

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Comparing EV/EV.pm (file contents): Revision 1.45 by root, Fri Nov 23 03:59:23 2007 UTC vs. Revision 1.71 by root, Mon Dec 17 07:24:12 2007 UTC

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Comparing EV/EV.pm (file contents):
Revision 1.45 by root, Fri Nov 23 03:59:23 2007 UTC vs.
Revision 1.71 by root, Mon Dec 17 07:24:12 2007 UTC