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

Comparing EV/EV.pm (file contents):
Revision 1.61 by root, Thu Dec 6 03:13:07 2007 UTC vs.
Revision 1.85 by root, Sat Mar 8 16:00:07 2008 UTC

…		…
35	warn "sigquit received\n";	35	warn "sigquit received\n";
36	};	36	};
37		37
38	# CHILD/PID STATUS CHANGES	38	# CHILD/PID STATUS CHANGES
39		39
40	my $w = EV::child 666, sub {	40	my $w = EV::child 666, 0, sub {
41	my ($w, $revents) = @_;	41	my ($w, $revents) = @_;
42	my $status = $w->rstatus;	42	my $status = $w->rstatus;
43	};	43	};
44		44
45	# STAT CHANGES	45	# STAT CHANGES
…		…
58	This module provides an interface to libev	58	This module provides an interface to libev
59	(L<http://software.schmorp.de/pkg/libev.html>). While the documentation	59	(L<http://software.schmorp.de/pkg/libev.html>). While the documentation
60	below is comprehensive, one might also consult the documentation of libev	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	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	62	watcher semantics or some discussion on the available backends, or how to
63	force a specific backend with C<LIBEV_FLAGS>.	63	force a specific backend with C<LIBEV_FLAGS>, or just about in any case
		64	because it has much more detailed information.
64		65
65	=cut	66	=cut
66		67
67	package EV;	68	package EV;
68		69
69	use strict;	70	use strict;
70		71
71	BEGIN {	72	BEGIN {
72	our $VERSION = '1.6';	73	our $VERSION = '3.1';
73	use XSLoader;	74	use XSLoader;
74	XSLoader::load "EV", $VERSION;	75	XSLoader::load "EV", $VERSION;
75	}	76	}
76		77
77	@EV::IO::ISA =	78	@EV::IO::ISA =
…		…
83	@EV::Idle::ISA =	84	@EV::Idle::ISA =
84	@EV::Prepare::ISA =	85	@EV::Prepare::ISA =
85	@EV::Check::ISA =	86	@EV::Check::ISA =
86	@EV::Embed::ISA =	87	@EV::Embed::ISA =
87	@EV::Fork::ISA =	88	@EV::Fork::ISA =
		89	@EV::Async::ISA =
88	"EV::Watcher";	90	"EV::Watcher";
89		91
		92	@EV::Loop::Default::ISA = "EV::Loop";
		93
		94	=head1 EVENT LOOPS
		95
		96	EV supports multiple event loops: There is a single "default event loop"
		97	that can handle everything including signals and child watchers, and any
		98	number of "dynamic event loops" that can use different backends (with
		99	various limitations), but no child and signal watchers.
		100
		101	You do not have to do anything to create the default event loop: When
		102	the module is loaded a suitable backend is selected on the premise of
		103	selecting a working backend (which for example rules out kqueue on most
		104	BSDs). Modules should, unless they have "special needs" always use the
		105	default loop as this is fastest (perl-wise), best supported by other
		106	modules (e.g. AnyEvent or Coro) and most portable event loop.
		107
		108	For specific programs you can create additional event loops dynamically.
		109
		110	=over 4
		111
		112	=item $loop = new EV::loop [$flags]
		113
		114	Create a new event loop as per the specified flags. Please refer to the
		115	C<ev_loop_new ()> function description in the libev documentation
		116	(L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#GLOBAL_FUNCTIONS>)
		117	for more info.
		118
		119	The loop will automatically be destroyed when it is no longer referenced
		120	by any watcher and the loop object goes out of scope.
		121
		122	Using C<EV::FLAG_FORKCHECK> is recommended, as only the default event loop
		123	is protected by this module.
		124
		125	=item $loop->loop_fork
		126
		127	Must be called after a fork in the child, before entering or continuing
		128	the event loop. An alternative is to use C<EV::FLAG_FORKCHECK> which calls
		129	this fucntion automatically, at some performance loss (refer to the libev
		130	documentation).
		131
		132	=item $loop = EV::default_loop [$flags]
		133
		134	Return the default loop (which is a singleton object).
		135
		136	=back
		137
		138
90	=head1 BASIC INTERFACE	139	=head1 BASIC INTERFACE
91		140
92	=over 4	141	=over 4
93		142
94	=item $EV::DIED	143	=item $EV::DIED
95		144
96	Must contain a reference to a function that is called when a callback	145	Must contain a reference to a function that is called when a callback
97	throws an exception (with $@ containing thr error). The default prints an	146	throws an exception (with $@ containing the error). The default prints an
98	informative message and continues.	147	informative message and continues.
99		148
100	If this callback throws an exception it will be silently ignored.	149	If this callback throws an exception it will be silently ignored.
101		150
		151	=item $flags = EV::supported_backends
		152
		153	=item $flags = EV::recommended_backends
		154
		155	=item $flags = EV::embeddable_backends
		156
		157	Returns the set (see C<EV::BACKEND_*> flags) of backends supported by this
		158	instance of EV, the set of recommended backends (supposed to be good) for
		159	this platform and the set of embeddable backends (see EMBED WATCHERS).
		160
		161	=item EV::sleep $seconds
		162
		163	Block the process for the given number of (fractional) seconds.
		164
102	=item $time = EV::time	165	=item $time = EV::time
103		166
104	Returns the current time in (fractional) seconds since the epoch.	167	Returns the current time in (fractional) seconds since the epoch.
105		168
106	=item $time = EV::now	169	=item $time = EV::now
		170
		171	=item $time = $loop->now
107		172
108	Returns the time the last event loop iteration has been started. This	173	Returns the time the last event loop iteration has been started. This
109	is the time that (relative) timers are based on, and refering to it is	174	is the time that (relative) timers are based on, and refering to it is
110	usually faster then calling EV::time.	175	usually faster then calling EV::time.
111		176
112	=item $method = EV::method	177	=item $backend = EV::backend
		178
		179	=item $backend = $loop->backend
113		180
114	Returns an integer describing the backend used by libev (EV::METHOD_SELECT	181	Returns an integer describing the backend used by libev (EV::METHOD_SELECT
115	or EV::METHOD_EPOLL).	182	or EV::METHOD_EPOLL).
116		183
117	=item EV::loop [$flags]	184	=item EV::loop [$flags]
		185
		186	=item $loop->loop ([$flags])
118		187
119	Begin checking for events and calling callbacks. It returns when a	188	Begin checking for events and calling callbacks. It returns when a
120	callback calls EV::unloop.	189	callback calls EV::unloop.
121		190
122	The $flags argument can be one of the following:	191	The $flags argument can be one of the following:
…		…
125	EV::LOOP_ONESHOT block at most once (wait, but do not loop)	194	EV::LOOP_ONESHOT block at most once (wait, but do not loop)
126	EV::LOOP_NONBLOCK do not block at all (fetch/handle events but do not wait)	195	EV::LOOP_NONBLOCK do not block at all (fetch/handle events but do not wait)
127		196
128	=item EV::unloop [$how]	197	=item EV::unloop [$how]
129		198
		199	=item $loop->unloop ([$how])
		200
130	When called with no arguments or an argument of EV::UNLOOP_ONE, makes the	201	When called with no arguments or an argument of EV::UNLOOP_ONE, makes the
131	innermost call to EV::loop return.	202	innermost call to EV::loop return.
132		203
133	When called with an argument of EV::UNLOOP_ALL, all calls to EV::loop will return as	204	When called with an argument of EV::UNLOOP_ALL, all calls to EV::loop will return as
134	fast as possible.	205	fast as possible.
135		206
136	=item $count = EV::loop_count	207	=item $count = EV::loop_count
137		208
		209	=item $count = $loop->loop_count
		210
138	Return the number of times the event loop has polled for new	211	Return the number of times the event loop has polled for new
139	events. Sometiems useful as a generation counter.	212	events. Sometiems useful as a generation counter.
140		213
141	=item EV::once $fh_or_undef, $events, $timeout, $cb->($revents)	214	=item EV::once $fh_or_undef, $events, $timeout, $cb->($revents)
		215
		216	=item $loop->once ($fh_or_undef, $events, $timeout, $cb->($revents))
142		217
143	This function rolls together an I/O and a timer watcher for a single	218	This function rolls together an I/O and a timer watcher for a single
144	one-shot event without the need for managing a watcher object.	219	one-shot event without the need for managing a watcher object.
145		220
146	If C<$fh_or_undef> is a filehandle or file descriptor, then C<$events>	221	If C<$fh_or_undef> is a filehandle or file descriptor, then C<$events>
…		…
152	If timeout is C<undef> or negative, then there will be no	227	If timeout is C<undef> or negative, then there will be no
153	timeout. Otherwise a EV::timer with this value will be started.	228	timeout. Otherwise a EV::timer with this value will be started.
154		229
155	When an error occurs or either the timeout or I/O watcher triggers, then	230	When an error occurs or either the timeout or I/O watcher triggers, then
156	the callback will be called with the received event set (in general	231	the callback will be called with the received event set (in general
157	you can expect it to be a combination of C<EV:ERROR>, C<EV::READ>,	232	you can expect it to be a combination of C<EV::ERROR>, C<EV::READ>,
158	C<EV::WRITE> and C<EV::TIMEOUT>).	233	C<EV::WRITE> and C<EV::TIMEOUT>).
159		234
160	EV::once doesn't return anything: the watchers stay active till either	235	EV::once doesn't return anything: the watchers stay active till either
161	of them triggers, then they will be stopped and freed, and the callback	236	of them triggers, then they will be stopped and freed, and the callback
162	invoked.	237	invoked.
163		238
164	=back	239	=item EV::feed_fd_event ($fd, $revents)
165		240
		241	=item $loop->feed_fd_event ($fd, $revents)
		242
		243	Feed an event on a file descriptor into EV. EV will react to this call as
		244	if the readyness notifications specified by C<$revents> (a combination of
		245	C<EV::READ> and C<EV::WRITE>) happened on the file descriptor C<$fd>.
		246
		247	=item EV::feed_signal_event ($signal)
		248
		249	Feed a signal event into EV. EV will react to this call as if the signal
		250	specified by C<$signal> had occured.
		251
		252	=item EV::set_io_collect_interval $time
		253
		254	=item $loop->set_io_collect_interval ($time)
		255
		256	=item EV::set_timeout_collect_interval $time
		257
		258	=item $loop->set_timeout_collect_interval ($time)
		259
		260	These advanced functions set the minimum block interval when polling for I/O events and the minimum
		261	wait interval for timer events. See the libev documentation at
		262	L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#FUNCTIONS_CONTROLLING_THE_EVENT_LOOP> for
		263	a more detailed discussion.
		264
		265	=back
		266
		267
166	=head2 WATCHER OBJECTS	268	=head1 WATCHER OBJECTS
167		269
168	A watcher is an object that gets created to record your interest in some	270	A watcher is an object that gets created to record your interest in some
169	event. For instance, if you want to wait for STDIN to become readable, you	271	event. For instance, if you want to wait for STDIN to become readable, you
170	would create an EV::io watcher for that:	272	would create an EV::io watcher for that:
171		273
172	my $watcher = EV::io *STDIN, EV::READ, sub {	274	my $watcher = EV::io *STDIN, EV::READ, sub {
173	my ($watcher, $revents) = @_;	275	my ($watcher, $revents) = @_;
174	warn "yeah, STDIN should not be readable without blocking!\n"	276	warn "yeah, STDIN should now be readable without blocking!\n"
175	};	277	};
176		278
177	All watchers can be active (waiting for events) or inactive (paused). Only	279	All watchers can be active (waiting for events) or inactive (paused). Only
178	active watchers will have their callbacks invoked. All callbacks will be	280	active watchers will have their callbacks invoked. All callbacks will be
179	called with at least two arguments: the watcher and a bitmask of received	281	called with at least two arguments: the watcher and a bitmask of received
180	events.	282	events.
181		283
182	Each watcher type has its associated bit in revents, so you can use the	284	Each watcher type has its associated bit in revents, so you can use the
183	same callback for multiple watchers. The event mask is named after the	285	same callback for multiple watchers. The event mask is named after the
184	type, i..e. EV::child sets EV::CHILD, EV::prepare sets EV::PREPARE,	286	type, i..e. EV::child sets EV::CHILD, EV::prepare sets EV::PREPARE,
185	EV::periodic sets EV::PERIODIC and so on, with the exception of IO events	287	EV::periodic sets EV::PERIODIC and so on, with the exception of I/O events
186	(which can set both EV::READ and EV::WRITE bits), and EV::timer (which	288	(which can set both EV::READ and EV::WRITE bits), and EV::timer (which
187	uses EV::TIMEOUT).	289	uses EV::TIMEOUT).
188		290
189	In the rare case where one wants to create a watcher but not start it at	291	In the rare case where one wants to create a watcher but not start it at
190	the same time, each constructor has a variant with a trailing C<_ns> in	292	the same time, each constructor has a variant with a trailing C<_ns> in
…		…
212		314
213	=item $w->stop	315	=item $w->stop
214		316
215	Stop a watcher if it is active. Also clear any pending events (events that	317	Stop a watcher if it is active. Also clear any pending events (events that
216	have been received but that didn't yet result in a callback invocation),	318	have been received but that didn't yet result in a callback invocation),
217	regardless of wether the watcher was active or not.	319	regardless of whether the watcher was active or not.
218		320
219	=item $bool = $w->is_active	321	=item $bool = $w->is_active
220		322
221	Returns true if the watcher is active, false otherwise.	323	Returns true if the watcher is active, false otherwise.
222		324
…		…
252	The default priority of any newly-created watcher is 0.	354	The default priority of any newly-created watcher is 0.
253		355
254	Note that the priority semantics have not yet been fleshed out and are	356	Note that the priority semantics have not yet been fleshed out and are
255	subject to almost certain change.	357	subject to almost certain change.
256		358
257	=item $w->trigger ($revents)	359	=item $w->invoke ($revents)
258		360
259	Call the callback now with the given event mask.	361	Call the callback now with the given event mask.
		362
		363	=item $w->feed_event ($revents)
		364
		365	Feed some events on this watcher into EV. EV will react to this call as if
		366	the watcher had received the given C<$revents> mask.
		367
		368	=item $revents = $w->clear_pending
		369
		370	If the watcher is pending, this function clears its pending status and
		371	returns its C<$revents> bitset (as if its callback was invoked). If the
		372	watcher isn't pending it does nothing and returns C<0>.
260		373
261	=item $previous_state = $w->keepalive ($bool)	374	=item $previous_state = $w->keepalive ($bool)
262		375
263	Normally, C<EV::loop> will return when there are no active watchers	376	Normally, C<EV::loop> will return when there are no active watchers
264	(which is a "deadlock" because no progress can be made anymore). This is	377	(which is a "deadlock" because no progress can be made anymore). This is
265	convinient because it allows you to start your watchers (and your jobs),	378	convinient because it allows you to start your watchers (and your jobs),
266	call C<EV::loop> once and when it returns you know that all your jobs are	379	call C<EV::loop> once and when it returns you know that all your jobs are
267	finished (or they forgot to register some watchers for their task :).	380	finished (or they forgot to register some watchers for their task :).
268		381
269	Sometimes, however, this gets in your way, for example when you the module	382	Sometimes, however, this gets in your way, for example when the module
270	that calls C<EV::loop> (usually the main program) is not the same module	383	that calls C<EV::loop> (usually the main program) is not the same module
271	as a long-living watcher (for example a DNS client module written by	384	as a long-living watcher (for example a DNS client module written by
272	somebody else even). Then you might want any outstanding requests to be	385	somebody else even). Then you might want any outstanding requests to be
273	handled, but you would not want to keep C<EV::loop> from returning just	386	handled, but you would not want to keep C<EV::loop> from returning just
274	because you happen to have this long-running UDP port watcher.	387	because you happen to have this long-running UDP port watcher.
…		…
277	though your watcher is active, it won't keep C<EV::loop> from returning.	390	though your watcher is active, it won't keep C<EV::loop> from returning.
278		391
279	The initial value for keepalive is true (enabled), and you cna change it	392	The initial value for keepalive is true (enabled), and you cna change it
280	any time.	393	any time.
281		394
282	Example: Register an IO watcher for some UDP socket but do not keep the	395	Example: Register an I/O watcher for some UDP socket but do not keep the
283	event loop from running just because of that watcher.	396	event loop from running just because of that watcher.
284		397
285	my $udp_socket = ...	398	my $udp_socket = ...
286	my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... };	399	my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... };
287	$udp_watcher->keepalive (0);	400	$1000udp_watcher->keepalive (0);
288		401
289	=back	402	=item $loop = $w->loop
290		403
		404	Return the loop that this watcher is attached to.
291		405
		406	=back
		407
		408
292	=head2 WATCHER TYPES	409	=head1 WATCHER TYPES
293		410
294	Each of the following subsections describes a single watcher type.	411	Each of the following subsections describes a single watcher type.
295		412
296	=head3 IO WATCHERS - is this file descriptor readable or writable?	413	=head3 I/O WATCHERS - is this file descriptor readable or writable?
297		414
298	=over 4	415	=over 4
299		416
300	=item $w = EV::io $fileno_or_fh, $eventmask, $callback	417	=item $w = EV::io $fileno_or_fh, $eventmask, $callback
301		418
302	=item $w = EV::io_ns $fileno_or_fh, $eventmask, $callback	419	=item $w = EV::io_ns $fileno_or_fh, $eventmask, $callback
		420
		421	=item $w = $loop->io ($fileno_or_fh, $eventmask, $callback)
		422
		423	=item $w = $loop->io_ns ($fileno_or_fh, $eventmask, $callback)
303		424
304	As long as the returned watcher object is alive, call the C<$callback>	425	As long as the returned watcher object is alive, call the C<$callback>
305	when at least one of events specified in C<$eventmask> occurs.	426	when at least one of events specified in C<$eventmask> occurs.
306		427
307	The $eventmask can be one or more of these constants ORed together:	428	The $eventmask can be one or more of these constants ORed together:
…		…
336	=over 4	457	=over 4
337		458
338	=item $w = EV::timer $after, $repeat, $callback	459	=item $w = EV::timer $after, $repeat, $callback
339		460
340	=item $w = EV::timer_ns $after, $repeat, $callback	461	=item $w = EV::timer_ns $after, $repeat, $callback
		462
		463	=item $w = $loop->timer ($after, $repeat, $callback)
		464
		465	=item $w = $loop->timer_ns ($after, $repeat, $callback)
341		466
342	Calls the callback after C<$after> seconds (which may be fractional). If	467	Calls the callback after C<$after> seconds (which may be fractional). If
343	C<$repeat> is non-zero, the timer will be restarted (with the $repeat	468	C<$repeat> is non-zero, the timer will be restarted (with the $repeat
344	value as $after) after the callback returns.	469	value as $after) after the callback returns.
345		470
…		…
386	=over 4	511	=over 4
387		512
388	=item $w = EV::periodic $at, $interval, $reschedule_cb, $callback	513	=item $w = EV::periodic $at, $interval, $reschedule_cb, $callback
389		514
390	=item $w = EV::periodic_ns $at, $interval, $reschedule_cb, $callback	515	=item $w = EV::periodic_ns $at, $interval, $reschedule_cb, $callback
		516
		517	=item $w = $loop->periodic ($at, $interval, $reschedule_cb, $callback)
		518
		519	=item $w = $loop->periodic_ns ($at, $interval, $reschedule_cb, $callback)
391		520
392	Similar to EV::timer, but is not based on relative timeouts but on	521	Similar to EV::timer, but is not based on relative timeouts but on
393	absolute times. Apart from creating "simple" timers that trigger "at" the	522	absolute times. Apart from creating "simple" timers that trigger "at" the
394	specified time, it can also be used for non-drifting absolute timers and	523	specified time, it can also be used for non-drifting absolute timers and
395	more complex, cron-like, setups that are not adversely affected by time	524	more complex, cron-like, setups that are not adversely affected by time
…		…
405	This time simply fires at the wallclock time C<$at> and doesn't repeat. It	534	This time simply fires at the wallclock time C<$at> and doesn't repeat. It
406	will not adjust when a time jump occurs, that is, if it is to be run	535	will not adjust when a time jump occurs, that is, if it is to be run
407	at January 1st 2011 then it will run when the system time reaches or	536	at January 1st 2011 then it will run when the system time reaches or
408	surpasses this time.	537	surpasses this time.
409		538
410	=item * non-repeating interval timer ($interval > 0, $reschedule_cb = 0)	539	=item * repeating interval timer ($interval > 0, $reschedule_cb = 0)
411		540
412	In this mode the watcher will always be scheduled to time out at the	541	In this mode the watcher will always be scheduled to time out at the
413	next C<$at + N * $interval> time (for some integer N) and then repeat,	542	next C<$at + N * $interval> time (for some integer N) and then repeat,
414	regardless of any time jumps.	543	regardless of any time jumps.
415		544
…		…
470		599
471	=item $w->again	600	=item $w->again
472		601
473	Simply stops and starts the watcher again.	602	Simply stops and starts the watcher again.
474		603
		604	=item $time = $w->at
		605
		606	Return the time that the watcher is expected to trigger next.
		607
475	=back	608	=back
476		609
477		610
478	=head3 SIGNAL WATCHERS - signal me when a signal gets signalled!	611	=head3 SIGNAL WATCHERS - signal me when a signal gets signalled!
479		612
…		…
512		645
513	=head3 CHILD WATCHERS - watch out for process status changes	646	=head3 CHILD WATCHERS - watch out for process status changes
514		647
515	=over 4	648	=over 4
516		649
517	=item $w = EV::child $pid, $callback	650	=item $w = EV::child $pid, $trace, $callback
518		651
519	=item $w = EV::child_ns $pid, $callback	652	=item $w = EV::child_ns $pid, $trace, $callback
520		653
		654	=item $w = $loop->child ($pid, $trace, $callback)
		655
		656	=item $w = $loop->child_ns ($pid, $trace, $callback)
		657
521	Call the callback when a status change for pid C<$pid> (or any pid if	658	Call the callback when a status change for pid C<$pid> (or any pid
522	C<$pid> is 0) has been received. More precisely: when the process receives	659	if C<$pid> is 0) has been received (a status change happens when the
		660	process terminates or is killed, or, when trace is true, additionally when
		661	it is stopped or continued). More precisely: when the process receives
523	a C<SIGCHLD>, EV will fetch the outstanding exit/wait status for all	662	a C<SIGCHLD>, EV will fetch the outstanding exit/wait status for all
524	changed/zombie children and call the callback.	663	changed/zombie children and call the callback.
525		664
526	It is valid (and fully supported) to install a child watcher after a child	665	It is valid (and fully supported) to install a child watcher after a child
527	has exited but before the event loop has started its next iteration (for	666	has exited but before the event loop has started its next iteration (for
…		…
534	You can have as many pid watchers per pid as you want, they will all be	673	You can have as many pid watchers per pid as you want, they will all be
535	called.	674	called.
536		675
537	The C<child_ns> variant doesn't start (activate) the newly created watcher.	676	The C<child_ns> variant doesn't start (activate) the newly created watcher.
538		677
539	=item $w->set ($pid)	678	=item $w->set ($pid, $trace)
540		679
541	Reconfigures the watcher, see the constructor above for details. Can be called at	680	Reconfigures the watcher, see the constructor above for details. Can be called at
542	any time.	681	any time.
543		682
544	=item $current_pid = $w->pid	683	=item $current_pid = $w->pid
545		684
546	=item $old_pid = $w->pid ($new_pid)
547
548	Returns the previously set process id and optionally set a new one.	685	Returns the previously set process id and optionally set a new one.
549		686
550	=item $exit_status = $w->rstatus	687	=item $exit_status = $w->rstatus
551		688
552	Return the exit/wait status (as returned by waitpid, see the waitpid entry	689	Return the exit/wait status (as returned by waitpid, see the waitpid entry
…		…
565	=over 4	702	=over 4
566		703
567	=item $w = EV::stat $path, $interval, $callback	704	=item $w = EV::stat $path, $interval, $callback
568		705
569	=item $w = EV::stat_ns $path, $interval, $callback	706	=item $w = EV::stat_ns $path, $interval, $callback
		707
		708	=item $w = $loop->stat ($path, $interval, $callback)
		709
		710	=item $w = $loop->stat_ns ($path, $interval, $callback)
570		711
571	Call the callback when a file status change has been detected on	712	Call the callback when a file status change has been detected on
572	C<$path>. The C<$path> does not need to exist, changing from "path exists"	713	C<$path>. The C<$path> does not need to exist, changing from "path exists"
573	to "path does not exist" is a status change like any other.	714	to "path does not exist" is a status change like any other.
574		715
…		…
645		786
646	=item $w = EV::idle $callback	787	=item $w = EV::idle $callback
647		788
648	=item $w = EV::idle_ns $callback	789	=item $w = EV::idle_ns $callback
649		790
650	Call the callback when there are no pending io, timer/periodic, signal or	791	=item $w = $loop->idle ($callback)
651	child events, i.e. when the process is idle.	792
		793	=item $w = $loop->idle_ns ($callback)
		794
		795	Call the callback when there are no other pending watchers of the same or
		796	higher priority (excluding check, prepare and other idle watchers of the
		797	same or lower priority, of course). They are called idle watchers because
		798	when the watcher is the highest priority pending event in the process, the
		799	process is considered to be idle at that priority.
		800
		801	If you want a watcher that is only ever called when I<no> other events are
		802	outstanding you have to set the priority to C<EV::MINPRI>.
652		803
653	The process will not block as long as any idle watchers are active, and	804	The process will not block as long as any idle watchers are active, and
654	they will be called repeatedly until stopped.	805	they will be called repeatedly until stopped.
655		806
		807	For example, if you have idle watchers at priority C<0> and C<1>, and
		808	an I/O watcher at priority C<0>, then the idle watcher at priority C<1>
		809	and the I/O watcher will always run when ready. Only when the idle watcher
		810	at priority C<1> is stopped and the I/O watcher at priority C<0> is not
		811	pending with the C<0>-priority idle watcher be invoked.
		812
656	The C<idle_ns> variant doesn't start (activate) the newly created watcher.	813	The C<idle_ns> variant doesn't start (activate) the newly created watcher.
657		814
658	=back	815	=back
659		816
660		817
…		…
663	=over 4	820	=over 4
664		821
665	=item $w = EV::prepare $callback	822	=item $w = EV::prepare $callback
666		823
667	=item $w = EV::prepare_ns $callback	824	=item $w = EV::prepare_ns $callback
		825
		826	=item $w = $loop->prepare ($callback)
		827
		828	=item $w = $loop->prepare_ns ($callback)
668		829
669	Call the callback just before the process would block. You can still	830	Call the callback just before the process would block. You can still
670	create/modify any watchers at this point.	831	create/modify any watchers at this point.
671		832
672	See the EV::check watcher, below, for explanations and an example.	833	See the EV::check watcher, below, for explanations and an example.
…		…
681	=over 4	842	=over 4
682		843
683	=item $w = EV::check $callback	844	=item $w = EV::check $callback
684		845
685	=item $w = EV::check_ns $callback	846	=item $w = EV::check_ns $callback
		847
		848	=item $w = $loop->check ($callback)
		849
		850	=item $w = $loop->check_ns ($callback)
686		851
687	Call the callback just after the process wakes up again (after it has	852	Call the callback just after the process wakes up again (after it has
688	gathered events), but before any other callbacks have been invoked.	853	gathered events), but before any other callbacks have been invoked.
689		854
690	This is used to integrate other event-based software into the EV	855	This is used to integrate other event-based software into the EV
…		…
700	or return;	865	or return;
701		866
702	# make the dispatcher handle any outstanding stuff	867	# make the dispatcher handle any outstanding stuff
703	... not shown	868	... not shown
704		869
705	# create an IO watcher for each and every socket	870	# create an I/O watcher for each and every socket
706	@snmp_watcher = (	871	@snmp_watcher = (
707	(map { EV::io $_, EV::READ, sub { } }	872	(map { EV::io $_, EV::READ, sub { } }
708	keys %{ $dispatcher->{_descriptors} }),	873	keys %{ $dispatcher->{_descriptors} }),
709		874
710	EV::timer +($event->[Net::SNMP::Dispatcher::_ACTIVE]	875	EV::timer +($event->[Net::SNMP::Dispatcher::_ACTIVE]
…		…
745		910
746	=item $w = EV::fork $callback	911	=item $w = EV::fork $callback
747		912
748	=item $w = EV::fork_ns $callback	913	=item $w = EV::fork_ns $callback
749		914
		915	=item $w = $loop->fork ($callback)
		916
		917	=item $w = $loop->fork_ns ($callback)
		918
750	Call the callback before the event loop is resumed in the child process	919	Call the callback before the event loop is resumed in the child process
751	after a fork.	920	after a fork.
752		921
753	The C<fork_ns> variant doesn't start (activate) the newly created watcher.	922	The C<fork_ns> variant doesn't start (activate) the newly created watcher.
754		923
755	=back	924	=back
		925
		926
		927	=head3 EMBED WATCHERS - when one backend isn't enough...
		928
		929	This is a rather advanced watcher type that lets you embed one event loop
		930	into another (currently only IO events are supported in the embedded
		931	loop, other types of watchers might be handled in a delayed or incorrect
		932	fashion and must not be used).
		933
		934	See the libev documentation at
		935	L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#code_ev_embed_code_when_one_backend_>
		936	for more details.
		937
		938	In short, this watcher is most useful on BSD systems without working
		939	kqueue to still be able to handle a large number of sockets:
		940
		941	my $socket_loop;
		942
		943	# check wether we use SELECT or POLL _and_ KQUEUE is supported
		944	if (
		945	(EV::backend & (EV::BACKEND_POLL \| EV::BACKEND_SELECT))
		946	&& (EV::supported_backends & EV::embeddable_backends & EV::BACKEND_KQUEUE)
		947	) {
		948	# use kqueue for sockets
		949	$socket_loop = new EV::Loop EV::BACKEND_KQUEUE \| EV::FLAG_NOENV;
		950	}
		951
		952	# use the default loop otherwise
		953	$socket_loop \|\|= EV::default_loop;
		954
		955	=over 4
		956
		957	=item $w = EV::embed $otherloop, $callback
		958
		959	=item $w = EV::embed_ns $otherloop, $callback
		960
		961	=item $w = $loop->embed ($otherloop, $callback)
		962
		963	=item $w = $loop->embed_ns ($otherloop, $callback)
		964
		965	Call the callback when the embedded event loop (C<$otherloop>) has any
		966	I/O activity. The C<$callback> should alwas be specified as C<undef> in
		967	this version of EV, which means the embedded event loop will be managed
		968	automatically.
		969
		970	The C<embed_ns> variant doesn't start (activate) the newly created watcher.
		971
		972	=back
		973
		974	=head3 ASYNC WATCHERS - how to wake up another event loop
		975
		976	Async watchers are provided by EV, but have little use in perl directly, as perl
		977	neither supports threads nor direct access to signal handlers or other
		978	contexts where they could be of value.
		979
		980	It is, however, possible to use them from the XS level.
		981
		982	Please see the libev documentation for further details.
756		983
757		984
758	=head1 PERL SIGNALS	985	=head1 PERL SIGNALS
759		986
760	While Perl signal handling (C<%SIG>) is not affected by EV, the behaviour	987	While Perl signal handling (C<%SIG>) is not affected by EV, the behaviour
…		…
769	to be called on every event loop iteration by installing a C<EV::check>	996	to be called on every event loop iteration by installing a C<EV::check>
770	watcher:	997	watcher:
771		998
772	my $async_check = EV::check sub { };	999	my $async_check = EV::check sub { };
773		1000
774	This ensures that perl shortly gets into control for a short time, and	1001	This ensures that perl gets into control for a short time to handle any
775	also ensures slower overall operation.	1002	pending signals, and also ensures (slightly) slower overall operation.
776		1003
777	=head1 THREADS	1004	=head1 THREADS
778		1005
779	Threads are not supported by this module in any way. Perl pseudo-threads	1006	Threads are not supported by this module in any way. Perl pseudo-threads
780	is evil stuff and must die. As soon as Perl gains real threads I will work	1007	is evil stuff and must die. As soon as Perl gains real threads I will work
…		…
802	our $DIED = sub {	1029	our $DIED = sub {
803	warn "EV: error in callback (ignoring): $@";	1030	warn "EV: error in callback (ignoring): $@";
804	};	1031	};
805		1032
806	default_loop	1033	default_loop
807	or die 'EV: cannot initialise libev backend. bad $ENV{LIBEV_METHODS}?';	1034	or die 'EV: cannot initialise libev backend. bad $ENV{LIBEV_FLAGS}?';
808		1035
809	1;	1036	1;
810		1037
811	=head1 SEE ALSO	1038	=head1 SEE ALSO
812		1039
813	L<EV::ADNS> (asynchronous dns), L<Glib::EV> (makes Glib/Gtk2 use EV as	1040	L<EV::ADNS> (asynchronous DNS), L<Glib::EV> (makes Glib/Gtk2 use EV as
814	event loop), L<Coro::EV> (efficient coroutines with EV).	1041	event loop), L<EV::Glib> (embed Glib into EV), L<Coro::EV> (efficient
		1042	coroutines with EV), L<Net::SNMP::EV> (asynchronous SNMP).
815		1043
816	=head1 AUTHOR	1044	=head1 AUTHOR
817		1045
818	Marc Lehmann <schmorp@schmorp.de>	1046	Marc Lehmann <schmorp@schmorp.de>
819	http://home.schmorp.de/	1047	http://home.schmorp.de/

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Comparing EV/EV.pm (file contents): Revision 1.61 by root, Thu Dec 6 03:13:07 2007 UTC vs. Revision 1.85 by root, Sat Mar 8 16:00:07 2008 UTC

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Comparing EV/EV.pm (file contents):
Revision 1.61 by root, Thu Dec 6 03:13:07 2007 UTC vs.
Revision 1.85 by root, Sat Mar 8 16:00:07 2008 UTC