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

Comparing EV/EV.pm (file contents):
Revision 1.57 by root, Wed Nov 28 17:32:24 2007 UTC vs.
Revision 1.84 by root, Fri Feb 1 13:08:54 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 = '1.4';	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
		207	=item $count = EV::loop_count
		208
		209	=item $count = $loop->loop_count
		210
		211	Return the number of times the event loop has polled for new
		212	events. Sometiems useful as a generation counter.
		213
136	=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))
137		217
138	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
139	one-shot event without the need for managing a watcher object.	219	one-shot event without the need for managing a watcher object.
140		220
141	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>
…		…
147	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
148	timeout. Otherwise a EV::timer with this value will be started.	228	timeout. Otherwise a EV::timer with this value will be started.
149		229
150	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
151	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
152	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>,
153	C<EV::WRITE> and C<EV::TIMEOUT>).	233	C<EV::WRITE> and C<EV::TIMEOUT>).
154		234
155	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
156	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
157	invoked.	237	invoked.
158		238
159	=back	239	=item EV::feed_fd_event ($fd, $revents)
160		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
161	=head2 WATCHER OBJECTS	268	=head1 WATCHER OBJECTS
162		269
163	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
164	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
165	would create an EV::io watcher for that:	272	would create an EV::io watcher for that:
166		273
167	my $watcher = EV::io *STDIN, EV::READ, sub {	274	my $watcher = EV::io *STDIN, EV::READ, sub {
168	my ($watcher, $revents) = @_;	275	my ($watcher, $revents) = @_;
169	warn "yeah, STDIN should not be readable without blocking!\n"	276	warn "yeah, STDIN should now be readable without blocking!\n"
170	};	277	};
171		278
172	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
173	active watchers will have their callbacks invoked. All callbacks will be	280	active watchers will have their callbacks invoked. All callbacks will be
174	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
175	events.	282	events.
176		283
177	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
178	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
179	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,
180	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
181	(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
182	uses EV::TIMEOUT).	289	uses EV::TIMEOUT).
183		290
184	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
185	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
…		…
207		314
208	=item $w->stop	315	=item $w->stop
209		316
210	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
211	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),
212	regardless of wether the watcher was active or not.	319	regardless of whether the watcher was active or not.
213		320
214	=item $bool = $w->is_active	321	=item $bool = $w->is_active
215		322
216	Returns true if the watcher is active, false otherwise.	323	Returns true if the watcher is active, false otherwise.
217		324
…		…
247	The default priority of any newly-created watcher is 0.	354	The default priority of any newly-created watcher is 0.
248		355
249	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
250	subject to almost certain change.	357	subject to almost certain change.
251		358
252	=item $w->trigger ($revents)	359	=item $w->invoke ($revents)
253		360
254	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>.
255		373
256	=item $previous_state = $w->keepalive ($bool)	374	=item $previous_state = $w->keepalive ($bool)
257		375
258	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
259	(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
260	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),
261	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
262	finished (or they forgot to register some watchers for their task :).	380	finished (or they forgot to register some watchers for their task :).
263		381
264	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
265	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
266	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
267	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
268	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
269	because you happen to have this long-running UDP port watcher.	387	because you happen to have this long-running UDP port watcher.
…		…
272	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.
273		391
274	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
275	any time.	393	any time.
276		394
277	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
278	event loop from running just because of that watcher.	396	event loop from running just because of that watcher.
279		397
280	my $udp_socket = ...	398	my $udp_socket = ...
281	my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... };	399	my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... };
282	$udp_watcher->keepalive (0);	400	$1000udp_watcher->keepalive (0);
283		401
284	=back	402	=item $loop = $w->loop
285		403
		404	Return the loop that this watcher is attached to.
286		405
		406	=back
		407
		408
287	=head2 WATCHER TYPES	409	=head1 WATCHER TYPES
288		410
289	Each of the following subsections describes a single watcher type.	411	Each of the following subsections describes a single watcher type.
290		412
291	=head3 IO WATCHERS - is this file descriptor readable or writable?	413	=head3 I/O WATCHERS - is this file descriptor readable or writable?
292		414
293	=over 4	415	=over 4
294		416
295	=item $w = EV::io $fileno_or_fh, $eventmask, $callback	417	=item $w = EV::io $fileno_or_fh, $eventmask, $callback
296		418
297	=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, $callback)
298		424
299	As long as the returned watcher object is alive, call the C<$callback>	425	As long as the returned watcher object is alive, call the C<$callback>
300	when at least one of events specified in C<$eventmask> occurs.	426	when at least one of events specified in C<$eventmask> occurs.
301		427
302	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:
…		…
331	=over 4	457	=over 4
332		458
333	=item $w = EV::timer $after, $repeat, $callback	459	=item $w = EV::timer $after, $repeat, $callback
334		460
335	=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, $callback)
336		466
337	Calls the callback after C<$after> seconds (which may be fractional). If	467	Calls the callback after C<$after> seconds (which may be fractional). If
338	C<$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
339	value as $after) after the callback returns.	469	value as $after) after the callback returns.
340		470
…		…
381	=over 4	511	=over 4
382		512
383	=item $w = EV::periodic $at, $interval, $reschedule_cb, $callback	513	=item $w = EV::periodic $at, $interval, $reschedule_cb, $callback
384		514
385	=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)
386		520
387	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
388	absolute times. Apart from creating "simple" timers that trigger "at" the	522	absolute times. Apart from creating "simple" timers that trigger "at" the
389	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
390	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
…		…
465		599
466	=item $w->again	600	=item $w->again
467		601
468	Simply stops and starts the watcher again.	602	Simply stops and starts the watcher again.
469		603
		604	=item $time = $w->at
		605
		606	Return the time that the watcher is expected to trigger next.
		607
470	=back	608	=back
471		609
472		610
473	=head3 SIGNAL WATCHERS - signal me when a signal gets signalled!	611	=head3 SIGNAL WATCHERS - signal me when a signal gets signalled!
474		612
…		…
507		645
508	=head3 CHILD WATCHERS - watch out for process status changes	646	=head3 CHILD WATCHERS - watch out for process status changes
509		647
510	=over 4	648	=over 4
511		649
512	=item $w = EV::child $pid, $callback	650	=item $w = EV::child $pid, $trace, $callback
513		651
514	=item $w = EV::child_ns $pid, $callback	652	=item $w = EV::child_ns $pid, $trace, $callback
515		653
		654	=item $w = $loop->child ($pid, $trace, $callback)
		655
		656	=item $w = $loop->child_ns ($pid, $trace, $callback)
		657
516	Call the callback when a status change for pid C<$pid> (or any pid if	658	Call the callback when a status change for pid C<$pid> (or any pid
517	C<$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
518	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
519	changed/zombie children and call the callback.	663	changed/zombie children and call the callback.
520		664
521	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
522	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
…		…
529	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
530	called.	674	called.
531		675
532	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.
533		677
534	=item $w->set ($pid)	678	=item $w->set ($pid, $trace)
535		679
536	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
537	any time.	681	any time.
538		682
539	=item $current_pid = $w->pid	683	=item $current_pid = $w->pid
540		684
541	=item $old_pid = $w->pid ($new_pid)
542
543	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.
544		686
545	=item $exit_status = $w->rstatus	687	=item $exit_status = $w->rstatus
546		688
547	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
…		…
560	=over 4	702	=over 4
561		703
562	=item $w = EV::stat $path, $interval, $callback	704	=item $w = EV::stat $path, $interval, $callback
563		705
564	=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, $callback)
565		711
566	Call the callback when a file status change has been detected on	712	Call the callback when a file status change has been detected on
567	C<$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"
568	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.
569		715
…		…
640		786
641	=item $w = EV::idle $callback	787	=item $w = EV::idle $callback
642		788
643	=item $w = EV::idle_ns $callback	789	=item $w = EV::idle_ns $callback
644		790
645	Call the callback when there are no pending io, timer/periodic, signal or	791	=item $w = $loop->idle ($callback)
646	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>.
647		803
648	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
649	they will be called repeatedly until stopped.	805	they will be called repeatedly until stopped.
650		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
651	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.
652		814
653	=back	815	=back
654		816
655		817
…		…
658	=over 4	820	=over 4
659		821
660	=item $w = EV::prepare $callback	822	=item $w = EV::prepare $callback
661		823
662	=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)
663		829
664	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
665	create/modify any watchers at this point.	831	create/modify any watchers at this point.
666		832
667	See the EV::check watcher, below, for explanations and an example.	833	See the EV::check watcher, below, for explanations and an example.
…		…
676	=over 4	842	=over 4
677		843
678	=item $w = EV::check $callback	844	=item $w = EV::check $callback
679		845
680	=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)
681		851
682	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
683	gathered events), but before any other callbacks have been invoked.	853	gathered events), but before any other callbacks have been invoked.
684		854
685	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
…		…
695	or return;	865	or return;
696		866
697	# make the dispatcher handle any outstanding stuff	867	# make the dispatcher handle any outstanding stuff
698	... not shown	868	... not shown
699		869
700	# create an IO watcher for each and every socket	870	# create an I/O watcher for each and every socket
701	@snmp_watcher = (	871	@snmp_watcher = (
702	(map { EV::io $_, EV::READ, sub { } }	872	(map { EV::io $_, EV::READ, sub { } }
703	keys %{ $dispatcher->{_descriptors} }),	873	keys %{ $dispatcher->{_descriptors} }),
704		874
705	EV::timer +($event->[Net::SNMP::Dispatcher::_ACTIVE]	875	EV::timer +($event->[Net::SNMP::Dispatcher::_ACTIVE]
…		…
740		910
741	=item $w = EV::fork $callback	911	=item $w = EV::fork $callback
742		912
743	=item $w = EV::fork_ns $callback	913	=item $w = EV::fork_ns $callback
744		914
		915	=item $w = $loop->fork ($callback)
		916
		917	=item $w = $loop->fork_ns ($callback)
		918
745	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
746	after a fork.	920	after a fork.
747		921
748	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.
749		923
750	=back	924	=back
751		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.
		983
		984
		985	=head1 PERL SIGNALS
		986
		987	While Perl signal handling (C<%SIG>) is not affected by EV, the behaviour
		988	with EV is as the same as any other C library: Perl-signals will only be
		989	handled when Perl runs, which means your signal handler might be invoked
		990	only the next time an event callback is invoked.
		991
		992	The solution is to use EV signal watchers (see C<EV::signal>), which will
		993	ensure proper operations with regards to other event watchers.
		994
		995	If you cannot do this for whatever reason, you can also force a watcher
		996	to be called on every event loop iteration by installing a C<EV::check>
		997	watcher:
		998
		999	my $async_check = EV::check sub { };
		1000
		1001	This ensures that perl gets into control for a short time to handle any
		1002	pending signals, and also ensures (slightly) slower overall operation.
752		1003
753	=head1 THREADS	1004	=head1 THREADS
754		1005
755	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
756	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
…		…
778	our $DIED = sub {	1029	our $DIED = sub {
779	warn "EV: error in callback (ignoring): $@";	1030	warn "EV: error in callback (ignoring): $@";
780	};	1031	};
781		1032
782	default_loop	1033	default_loop
783	or die 'EV: cannot initialise libev backend. bad $ENV{LIBEV_METHODS}?';	1034	or die 'EV: cannot initialise libev backend. bad $ENV{LIBEV_FLAGS}?';
784		1035
785	1;	1036	1;
786		1037
787	=head1 SEE ALSO	1038	=head1 SEE ALSO
788		1039
789	L<EV::DNS>.	1040	L<EV::ADNS> (asynchronous DNS), L<Glib::EV> (makes Glib/Gtk2 use EV as
		1041	event loop), L<EV::Glib> (embed Glib into EV), L<Coro::EV> (efficient
		1042	coroutines with EV), L<Net::SNMP::EV> (asynchronous SNMP).
790		1043
791	=head1 AUTHOR	1044	=head1 AUTHOR
792		1045
793	Marc Lehmann <schmorp@schmorp.de>	1046	Marc Lehmann <schmorp@schmorp.de>
794	http://home.schmorp.de/	1047	http://home.schmorp.de/

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Comparing EV/EV.pm (file contents): Revision 1.57 by root, Wed Nov 28 17:32:24 2007 UTC vs. Revision 1.84 by root, Fri Feb 1 13:08:54 2008 UTC

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Comparing EV/EV.pm (file contents):
Revision 1.57 by root, Wed Nov 28 17:32:24 2007 UTC vs.
Revision 1.84 by root, Fri Feb 1 13:08:54 2008 UTC