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

Comparing EV/EV.pm (file contents):
Revision 1.58 by root, Wed Nov 28 19:22:16 2007 UTC vs.
Revision 1.104 by root, Thu Oct 2 12:26:25 2008 UTC

…		…
2		2
3	EV - perl interface to libev, a high performance full-featured event loop	3	EV - perl interface to libev, a high performance full-featured event loop
4		4
5	=head1 SYNOPSIS	5	=head1 SYNOPSIS
6		6
7	use EV;	7	use EV;
		8
		9	# TIMERS
		10
		11	my $w = EV::timer 2, 0, sub {
		12	warn "is called after 2s";
		13	};
		14
		15	my $w = EV::timer 2, 2, sub {
		16	warn "is called roughly every 2s (repeat = 2)";
		17	};
		18
		19	undef $w; # destroy event watcher again
		20
		21	my $w = EV::periodic 0, 60, 0, sub {
		22	warn "is called every minute, on the minute, exactly";
		23	};
		24
		25	# IO
		26
		27	my $w = EV::io *STDIN, EV::READ, sub {
		28	my ($w, $revents) = @_; # all callbacks receive the watcher and event mask
		29	warn "stdin is readable, you entered: ", <STDIN>;
		30	};
		31
		32	# SIGNALS
		33
		34	my $w = EV::signal 'QUIT', sub {
		35	warn "sigquit received\n";
		36	};
		37
		38	# CHILD/PID STATUS CHANGES
8		39
9	# TIMERS	40	my $w = EV::child 666, 0, sub {
		41	my ($w, $revents) = @_;
		42	my $status = $w->rstatus;
		43	};
10		44
11	my $w = EV::timer 2, 0, sub {
12	warn "is called after 2s";
13	};
14
15	my $w = EV::timer 2, 2, sub {
16	warn "is called roughly every 2s (repeat = 2)";
17	};
18
19	undef $w; # destroy event watcher again
20
21	my $w = EV::periodic 0, 60, 0, sub {
22	warn "is called every minute, on the minute, exactly";
23	};
24
25	# IO
26
27	my $w = EV::io *STDIN, EV::READ, sub {
28	my ($w, $revents) = @_; # all callbacks receive the watcher and event mask
29	warn "stdin is readable, you entered: ", <STDIN>;
30	};
31
32	# SIGNALS
33
34	my $w = EV::signal 'QUIT', sub {
35	warn "sigquit received\n";
36	};
37
38	# CHILD/PID STATUS CHANGES
39
40	my $w = EV::child 666, sub {
41	my ($w, $revents) = @_;
42	my $status = $w->rstatus;
43	};
44
45	# STAT CHANGES	45	# STAT CHANGES
46	my $w = EV::stat "/etc/passwd", 10, sub {	46	my $w = EV::stat "/etc/passwd", 10, sub {
47	my ($w, $revents) = @_;	47	my ($w, $revents) = @_;
48	warn $w->path, " has changed somehow.\n";	48	warn $w->path, " has changed somehow.\n";
49	};	49	};
50		50
51	# MAINLOOP	51	# MAINLOOP
52	EV::loop; # loop until EV::unloop is called or all watchers stop	52	EV::loop; # loop until EV::unloop is called or all watchers stop
53	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
54	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
55		55
56	=head1 DESCRIPTION	56	=head1 DESCRIPTION
57		57
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
61	itself (L<http://cvs.schmorp.de/libev/ev.html>) for more subtle details on	61	libev itself (L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod> or
62	watcher semantics or some discussion on the available backends, or how to	62	F<perldoc EV::c_doc>) for more subtle details on watcher semantics or some
63	force a specific backend with C<LIBEV_FLAGS>.	63	discussion on the available backends, or how to force a specific backend
		64	with C<LIBEV_FLAGS>, or just about in any case because it has much more
		65	detailed information.
		66
		67	This module is very fast and scalable. It is actually so fast that you
		68	can use it through the L<AnyEvent> module, stay portable to other event
		69	loops (if you don't rely on any watcher types not available through it)
		70	and still be faster than with any other event loop currently supported in
		71	Perl.
64		72
65	=cut	73	=cut
66		74
67	package EV;	75	package EV;
68		76
		77	no warnings;
69	use strict;	78	use strict;
70		79
71	BEGIN {	80	BEGIN {
72	our $VERSION = '1.5';	81	our $VERSION = '3.44';
73	use XSLoader;	82	use XSLoader;
74	XSLoader::load "EV", $VERSION;	83	XSLoader::load "EV", $VERSION;
75	}	84	}
76		85
77	@EV::IO::ISA =	86	@EV::IO::ISA =
…		…
83	@EV::Idle::ISA =	92	@EV::Idle::ISA =
84	@EV::Prepare::ISA =	93	@EV::Prepare::ISA =
85	@EV::Check::ISA =	94	@EV::Check::ISA =
86	@EV::Embed::ISA =	95	@EV::Embed::ISA =
87	@EV::Fork::ISA =	96	@EV::Fork::ISA =
		97	@EV::Async::ISA =
88	"EV::Watcher";	98	"EV::Watcher";
89		99
		100	@EV::Loop::Default::ISA = "EV::Loop";
		101
		102	=head1 EVENT LOOPS
		103
		104	EV supports multiple event loops: There is a single "default event loop"
		105	that can handle everything including signals and child watchers, and any
		106	number of "dynamic event loops" that can use different backends (with
		107	various limitations), but no child and signal watchers.
		108
		109	You do not have to do anything to create the default event loop: When
		110	the module is loaded a suitable backend is selected on the premise of
		111	selecting a working backend (which for example rules out kqueue on most
		112	BSDs). Modules should, unless they have "special needs" always use the
		113	default loop as this is fastest (perl-wise), best supported by other
		114	modules (e.g. AnyEvent or Coro) and most portable event loop.
		115
		116	For specific programs you can create additional event loops dynamically.
		117
		118	If you want to take avdantage of kqueue (which often works properly for
		119	sockets only) even though the default loop doesn't enable it, you can
		120	I<embed> a kqueue loop into the default loop: running the default loop
		121	will then also service the kqueue loop to some extent. See the example in
		122	the section about embed watchers for an example on how to achieve that.
		123
		124	=over 4
		125
		126	=item $loop = new EV::loop [$flags]
		127
		128	Create a new event loop as per the specified flags. Please refer to
		129	the C<ev_loop_new ()> function description in the libev documentation
		130	(L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#GLOBAL_FUNCTIONS>,
		131	or locally-installed as F<EV::c_doc> manpage) for more info.
		132
		133	The loop will automatically be destroyed when it is no longer referenced
		134	by any watcher and the loop object goes out of scope.
		135
		136	If you are not embedding the loop, then Using C<EV::FLAG_FORKCHECK>
		137	is recommended, as only the default event loop is protected by this
		138	module. If you I<are> embedding this loop in the default loop, this is not
		139	necessary, as C<EV::embed> automatically does the right thing on fork.
		140
		141	=item $loop->loop_fork
		142
		143	Must be called after a fork in the child, before entering or continuing
		144	the event loop. An alternative is to use C<EV::FLAG_FORKCHECK> which calls
		145	this function automatically, at some performance loss (refer to the libev
		146	documentation).
		147
		148	=item $loop->loop_verify
		149
		150	Calls C<ev_verify> to make internal consistency checks (for debugging
		151	libev) and abort the program if any data structures were found to be
		152	corrupted.
		153
		154	=item $loop = EV::default_loop [$flags]
		155
		156	Return the default loop (which is a singleton object). Since this module
		157	already creates the default loop with default flags, specifying flags here
		158	will not have any effect unless you destroy the default loop first, which
		159	isn't supported. So in short: don't do it, and if you break it, you get to
		160	keep the pieces.
		161
		162	=back
		163
		164
90	=head1 BASIC INTERFACE	165	=head1 BASIC INTERFACE
91		166
92	=over 4	167	=over 4
93		168
94	=item $EV::DIED	169	=item $EV::DIED
95		170
96	Must contain a reference to a function that is called when a callback	171	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	172	throws an exception (with $@ containing the error). The default prints an
98	informative message and continues.	173	informative message and continues.
99		174
100	If this callback throws an exception it will be silently ignored.	175	If this callback throws an exception it will be silently ignored.
101		176
		177	=item $flags = EV::supported_backends
		178
		179	=item $flags = EV::recommended_backends
		180
		181	=item $flags = EV::embeddable_backends
		182
		183	Returns the set (see C<EV::BACKEND_*> flags) of backends supported by this
		184	instance of EV, the set of recommended backends (supposed to be good) for
		185	this platform and the set of embeddable backends (see EMBED WATCHERS).
		186
		187	=item EV::sleep $seconds
		188
		189	Block the process for the given number of (fractional) seconds.
		190
102	=item $time = EV::time	191	=item $time = EV::time
103		192
104	Returns the current time in (fractional) seconds since the epoch.	193	Returns the current time in (fractional) seconds since the epoch.
105		194
106	=item $time = EV::now	195	=item $time = EV::now
		196
		197	=item $time = $loop->now
107		198
108	Returns the time the last event loop iteration has been started. This	199	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	200	is the time that (relative) timers are based on, and refering to it is
110	usually faster then calling EV::time.	201	usually faster then calling EV::time.
111		202
112	=item $method = EV::method	203	=item $backend = EV::backend
		204
		205	=item $backend = $loop->backend
113		206
114	Returns an integer describing the backend used by libev (EV::METHOD_SELECT	207	Returns an integer describing the backend used by libev (EV::METHOD_SELECT
115	or EV::METHOD_EPOLL).	208	or EV::METHOD_EPOLL).
116		209
117	=item EV::loop [$flags]	210	=item EV::loop [$flags]
		211
		212	=item $loop->loop ([$flags])
118		213
119	Begin checking for events and calling callbacks. It returns when a	214	Begin checking for events and calling callbacks. It returns when a
120	callback calls EV::unloop.	215	callback calls EV::unloop.
121		216
122	The $flags argument can be one of the following:	217	The $flags argument can be one of the following:
…		…
125	EV::LOOP_ONESHOT block at most once (wait, but do not loop)	220	EV::LOOP_ONESHOT block at most once (wait, but do not loop)
126	EV::LOOP_NONBLOCK do not block at all (fetch/handle events but do not wait)	221	EV::LOOP_NONBLOCK do not block at all (fetch/handle events but do not wait)
127		222
128	=item EV::unloop [$how]	223	=item EV::unloop [$how]
129		224
		225	=item $loop->unloop ([$how])
		226
130	When called with no arguments or an argument of EV::UNLOOP_ONE, makes the	227	When called with no arguments or an argument of EV::UNLOOP_ONE, makes the
131	innermost call to EV::loop return.	228	innermost call to EV::loop return.
132		229
133	When called with an argument of EV::UNLOOP_ALL, all calls to EV::loop will return as	230	When called with an argument of EV::UNLOOP_ALL, all calls to EV::loop will return as
134	fast as possible.	231	fast as possible.
135		232
		233	=item $count = EV::loop_count
		234
		235	=item $count = $loop->loop_count
		236
		237	Return the number of times the event loop has polled for new
		238	events. Sometiems useful as a generation counter.
		239
136	=item EV::once $fh_or_undef, $events, $timeout, $cb->($revents)	240	=item EV::once $fh_or_undef, $events, $timeout, $cb->($revents)
		241
		242	=item $loop->once ($fh_or_undef, $events, $timeout, $cb->($revents))
137		243
138	This function rolls together an I/O and a timer watcher for a single	244	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.	245	one-shot event without the need for managing a watcher object.
140		246
141	If C<$fh_or_undef> is a filehandle or file descriptor, then C<$events>	247	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	253	If timeout is C<undef> or negative, then there will be no
148	timeout. Otherwise a EV::timer with this value will be started.	254	timeout. Otherwise a EV::timer with this value will be started.
149		255
150	When an error occurs or either the timeout or I/O watcher triggers, then	256	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	257	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>,	258	you can expect it to be a combination of C<EV::ERROR>, C<EV::READ>,
153	C<EV::WRITE> and C<EV::TIMEOUT>).	259	C<EV::WRITE> and C<EV::TIMEOUT>).
154		260
155	EV::once doesn't return anything: the watchers stay active till either	261	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	262	of them triggers, then they will be stopped and freed, and the callback
157	invoked.	263	invoked.
158		264
159	=back	265	=item EV::feed_fd_event ($fd, $revents)
160		266
		267	=item $loop->feed_fd_event ($fd, $revents)
		268
		269	Feed an event on a file descriptor into EV. EV will react to this call as
		270	if the readyness notifications specified by C<$revents> (a combination of
		271	C<EV::READ> and C<EV::WRITE>) happened on the file descriptor C<$fd>.
		272
		273	=item EV::feed_signal_event ($signal)
		274
		275	Feed a signal event into EV. EV will react to this call as if the signal
		276	specified by C<$signal> had occured.
		277
		278	=item EV::set_io_collect_interval $time
		279
		280	=item $loop->set_io_collect_interval ($time)
		281
		282	=item EV::set_timeout_collect_interval $time
		283
		284	=item $loop->set_timeout_collect_interval ($time)
		285
		286	These advanced functions set the minimum block interval when polling for I/O events and the minimum
		287	wait interval for timer events. See the libev documentation at
		288	L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#FUNCTIONS_CONTROLLING_THE_EVENT_LOOP>
		289	(locally installed as F<EV::c_doc>) for a more detailed discussion.
		290
		291	=back
		292
		293
161	=head2 WATCHER OBJECTS	294	=head1 WATCHER OBJECTS
162		295
163	A watcher is an object that gets created to record your interest in some	296	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	297	event. For instance, if you want to wait for STDIN to become readable, you
165	would create an EV::io watcher for that:	298	would create an EV::io watcher for that:
166		299
167	my $watcher = EV::io *STDIN, EV::READ, sub {	300	my $watcher = EV::io *STDIN, EV::READ, sub {
168	my ($watcher, $revents) = @_;	301	my ($watcher, $revents) = @_;
169	warn "yeah, STDIN should not be readable without blocking!\n"	302	warn "yeah, STDIN should now be readable without blocking!\n"
170	};	303	};
171		304
172	All watchers can be active (waiting for events) or inactive (paused). Only	305	All watchers can be active (waiting for events) or inactive (paused). Only
173	active watchers will have their callbacks invoked. All callbacks will be	306	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	307	called with at least two arguments: the watcher and a bitmask of received
175	events.	308	events.
176		309
177	Each watcher type has its associated bit in revents, so you can use the	310	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	311	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,	312	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	313	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	314	(which can set both EV::READ and EV::WRITE bits), and EV::timer (which
182	uses EV::TIMEOUT).	315	uses EV::TIMEOUT).
183		316
184	In the rare case where one wants to create a watcher but not start it at	317	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	318	the same time, each constructor has a variant with a trailing C<_ns> in
…		…
207		340
208	=item $w->stop	341	=item $w->stop
209		342
210	Stop a watcher if it is active. Also clear any pending events (events that	343	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),	344	have been received but that didn't yet result in a callback invocation),
212	regardless of wether the watcher was active or not.	345	regardless of whether the watcher was active or not.
213		346
214	=item $bool = $w->is_active	347	=item $bool = $w->is_active
215		348
216	Returns true if the watcher is active, false otherwise.	349	Returns true if the watcher is active, false otherwise.
217		350
…		…
247	The default priority of any newly-created watcher is 0.	380	The default priority of any newly-created watcher is 0.
248		381
249	Note that the priority semantics have not yet been fleshed out and are	382	Note that the priority semantics have not yet been fleshed out and are
250	subject to almost certain change.	383	subject to almost certain change.
251		384
252	=item $w->trigger ($revents)	385	=item $w->invoke ($revents)
253		386
254	Call the callback now with the given event mask.	387	Call the callback now with the given event mask.
		388
		389	=item $w->feed_event ($revents)
		390
		391	Feed some events on this watcher into EV. EV will react to this call as if
		392	the watcher had received the given C<$revents> mask.
		393
		394	=item $revents = $w->clear_pending
		395
		396	If the watcher is pending, this function clears its pending status and
		397	returns its C<$revents> bitset (as if its callback was invoked). If the
		398	watcher isn't pending it does nothing and returns C<0>.
255		399
256	=item $previous_state = $w->keepalive ($bool)	400	=item $previous_state = $w->keepalive ($bool)
257		401
258	Normally, C<EV::loop> will return when there are no active watchers	402	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	403	(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),	404	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	405	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 :).	406	finished (or they forgot to register some watchers for their task :).
263		407
264	Sometimes, however, this gets in your way, for example when you the module	408	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	409	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	410	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	411	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	412	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.	413	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.	416	though your watcher is active, it won't keep C<EV::loop> from returning.
273		417
274	The initial value for keepalive is true (enabled), and you cna change it	418	The initial value for keepalive is true (enabled), and you cna change it
275	any time.	419	any time.
276		420
277	Example: Register an IO watcher for some UDP socket but do not keep the	421	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.	422	event loop from running just because of that watcher.
279		423
280	my $udp_socket = ...	424	my $udp_socket = ...
281	my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... };	425	my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... };
282	$udp_watcher->keepalive (0);	426	$udp_watcher->keepalive (0);
283		427
284	=back	428	=item $loop = $w->loop
285		429
		430	Return the loop that this watcher is attached to.
286		431
		432	=back
		433
		434
287	=head2 WATCHER TYPES	435	=head1 WATCHER TYPES
288		436
289	Each of the following subsections describes a single watcher type.	437	Each of the following subsections describes a single watcher type.
290		438
291	=head3 IO WATCHERS - is this file descriptor readable or writable?	439	=head3 I/O WATCHERS - is this file descriptor readable or writable?
292		440
293	=over 4	441	=over 4
294		442
295	=item $w = EV::io $fileno_or_fh, $eventmask, $callback	443	=item $w = EV::io $fileno_or_fh, $eventmask, $callback
296		444
297	=item $w = EV::io_ns $fileno_or_fh, $eventmask, $callback	445	=item $w = EV::io_ns $fileno_or_fh, $eventmask, $callback
		446
		447	=item $w = $loop->io ($fileno_or_fh, $eventmask, $callback)
		448
		449	=item $w = $loop->io_ns ($fileno_or_fh, $eventmask, $callback)
298		450
299	As long as the returned watcher object is alive, call the C<$callback>	451	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.	452	when at least one of events specified in C<$eventmask> occurs.
301		453
302	The $eventmask can be one or more of these constants ORed together:	454	The $eventmask can be one or more of these constants ORed together:
…		…
331	=over 4	483	=over 4
332		484
333	=item $w = EV::timer $after, $repeat, $callback	485	=item $w = EV::timer $after, $repeat, $callback
334		486
335	=item $w = EV::timer_ns $after, $repeat, $callback	487	=item $w = EV::timer_ns $after, $repeat, $callback
		488
		489	=item $w = $loop->timer ($after, $repeat, $callback)
		490
		491	=item $w = $loop->timer_ns ($after, $repeat, $callback)
336		492
337	Calls the callback after C<$after> seconds (which may be fractional). If	493	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 $repeat	494	C<$repeat> is non-zero, the timer will be restarted (with the $repeat
339	value as $after) after the callback returns.	495	value as $after) after the callback returns.
340		496
…		…
381	=over 4	537	=over 4
382		538
383	=item $w = EV::periodic $at, $interval, $reschedule_cb, $callback	539	=item $w = EV::periodic $at, $interval, $reschedule_cb, $callback
384		540
385	=item $w = EV::periodic_ns $at, $interval, $reschedule_cb, $callback	541	=item $w = EV::periodic_ns $at, $interval, $reschedule_cb, $callback
		542
		543	=item $w = $loop->periodic ($at, $interval, $reschedule_cb, $callback)
		544
		545	=item $w = $loop->periodic_ns ($at, $interval, $reschedule_cb, $callback)
386		546
387	Similar to EV::timer, but is not based on relative timeouts but on	547	Similar to EV::timer, but is not based on relative timeouts but on
388	absolute times. Apart from creating "simple" timers that trigger "at" the	548	absolute times. Apart from creating "simple" timers that trigger "at" the
389	specified time, it can also be used for non-drifting absolute timers and	549	specified time, it can also be used for non-drifting absolute timers and
390	more complex, cron-like, setups that are not adversely affected by time	550	more complex, cron-like, setups that are not adversely affected by time
…		…
400	This time simply fires at the wallclock time C<$at> and doesn't repeat. It	560	This time simply fires at the wallclock time C<$at> and doesn't repeat. It
401	will not adjust when a time jump occurs, that is, if it is to be run	561	will not adjust when a time jump occurs, that is, if it is to be run
402	at January 1st 2011 then it will run when the system time reaches or	562	at January 1st 2011 then it will run when the system time reaches or
403	surpasses this time.	563	surpasses this time.
404		564
405	=item * non-repeating interval timer ($interval > 0, $reschedule_cb = 0)	565	=item * repeating interval timer ($interval > 0, $reschedule_cb = 0)
406		566
407	In this mode the watcher will always be scheduled to time out at the	567	In this mode the watcher will always be scheduled to time out at the
408	next C<$at + N * $interval> time (for some integer N) and then repeat,	568	next C<$at + N * $interval> time (for some integer N) and then repeat,
409	regardless of any time jumps.	569	regardless of any time jumps.
410		570
…		…
428	time the periodic watcher gets scheduled, the reschedule callback	588	time the periodic watcher gets scheduled, the reschedule callback
429	($reschedule_cb) will be called with the watcher as first, and the current	589	($reschedule_cb) will be called with the watcher as first, and the current
430	time as second argument.	590	time as second argument.
431		591
432	I<This callback MUST NOT stop or destroy this or any other periodic	592	I<This callback MUST NOT stop or destroy this or any other periodic
433	watcher, ever>. If you need to stop it, return 1e30 and stop it	593	watcher, ever, and MUST NOT call any event loop functions or methods>. If
434	afterwards.	594	you need to stop it, return 1e30 and stop it afterwards. You may create
		595	and start a C<EV::prepare> watcher for this task.
435		596
436	It must return the next time to trigger, based on the passed time value	597	It must return the next time to trigger, based on the passed time value
437	(that is, the lowest time value larger than to the second argument). It	598	(that is, the lowest time value larger than or equal to to the second
438	will usually be called just before the callback will be triggered, but	599	argument). It will usually be called just before the callback will be
439	might be called at other times, too.	600	triggered, but might be called at other times, too.
440		601
441	This can be used to create very complex timers, such as a timer that	602	This can be used to create very complex timers, such as a timer that
442	triggers on each midnight, local time (actually 24 hours after the last	603	triggers on each midnight, local time (actually 24 hours after the last
443	midnight, to keep the example simple. If you know a way to do it correctly	604	midnight, to keep the example simple. If you know a way to do it correctly
444	in about the same space (without requiring elaborate modules), drop me a	605	in about the same space (without requiring elaborate modules), drop me a
…		…
465		626
466	=item $w->again	627	=item $w->again
467		628
468	Simply stops and starts the watcher again.	629	Simply stops and starts the watcher again.
469		630
		631	=item $time = $w->at
		632
		633	Return the time that the watcher is expected to trigger next.
		634
470	=back	635	=back
471		636
472		637
473	=head3 SIGNAL WATCHERS - signal me when a signal gets signalled!	638	=head3 SIGNAL WATCHERS - signal me when a signal gets signalled!
474		639
…		…
507		672
508	=head3 CHILD WATCHERS - watch out for process status changes	673	=head3 CHILD WATCHERS - watch out for process status changes
509		674
510	=over 4	675	=over 4
511		676
512	=item $w = EV::child $pid, $callback	677	=item $w = EV::child $pid, $trace, $callback
513		678
514	=item $w = EV::child_ns $pid, $callback	679	=item $w = EV::child_ns $pid, $trace, $callback
515		680
		681	=item $w = $loop->child ($pid, $trace, $callback)
		682
		683	=item $w = $loop->child_ns ($pid, $trace, $callback)
		684
516	Call the callback when a status change for pid C<$pid> (or any pid if	685	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	686	if C<$pid> is 0) has been received (a status change happens when the
		687	process terminates or is killed, or, when trace is true, additionally when
		688	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	689	a C<SIGCHLD>, EV will fetch the outstanding exit/wait status for all
519	changed/zombie children and call the callback.	690	changed/zombie children and call the callback.
520		691
521	It is valid (and fully supported) to install a child watcher after a child	692	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	693	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	700	You can have as many pid watchers per pid as you want, they will all be
530	called.	701	called.
531		702
532	The C<child_ns> variant doesn't start (activate) the newly created watcher.	703	The C<child_ns> variant doesn't start (activate) the newly created watcher.
533		704
534	=item $w->set ($pid)	705	=item $w->set ($pid, $trace)
535		706
536	Reconfigures the watcher, see the constructor above for details. Can be called at	707	Reconfigures the watcher, see the constructor above for details. Can be called at
537	any time.	708	any time.
538		709
539	=item $current_pid = $w->pid	710	=item $current_pid = $w->pid
540		711
541	=item $old_pid = $w->pid ($new_pid)
542
543	Returns the previously set process id and optionally set a new one.	712	Returns the previously set process id and optionally set a new one.
544		713
545	=item $exit_status = $w->rstatus	714	=item $exit_status = $w->rstatus
546		715
547	Return the exit/wait status (as returned by waitpid, see the waitpid entry	716	Return the exit/wait status (as returned by waitpid, see the waitpid entry
…		…
560	=over 4	729	=over 4
561		730
562	=item $w = EV::stat $path, $interval, $callback	731	=item $w = EV::stat $path, $interval, $callback
563		732
564	=item $w = EV::stat_ns $path, $interval, $callback	733	=item $w = EV::stat_ns $path, $interval, $callback
		734
		735	=item $w = $loop->stat ($path, $interval, $callback)
		736
		737	=item $w = $loop->stat_ns ($path, $interval, $callback)
565		738
566	Call the callback when a file status change has been detected on	739	Call the callback when a file status change has been detected on
567	C<$path>. The C<$path> does not need to exist, changing from "path exists"	740	C<$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.	741	to "path does not exist" is a status change like any other.
569		742
…		…
640		813
641	=item $w = EV::idle $callback	814	=item $w = EV::idle $callback
642		815
643	=item $w = EV::idle_ns $callback	816	=item $w = EV::idle_ns $callback
644		817
645	Call the callback when there are no pending io, timer/periodic, signal or	818	=item $w = $loop->idle ($callback)
646	child events, i.e. when the process is idle.	819
		820	=item $w = $loop->idle_ns ($callback)
		821
		822	Call the callback when there are no other pending watchers of the same or
		823	higher priority (excluding check, prepare and other idle watchers of the
		824	same or lower priority, of course). They are called idle watchers because
		825	when the watcher is the highest priority pending event in the process, the
		826	process is considered to be idle at that priority.
		827
		828	If you want a watcher that is only ever called when I<no> other events are
		829	outstanding you have to set the priority to C<EV::MINPRI>.
647		830
648	The process will not block as long as any idle watchers are active, and	831	The process will not block as long as any idle watchers are active, and
649	they will be called repeatedly until stopped.	832	they will be called repeatedly until stopped.
650		833
		834	For example, if you have idle watchers at priority C<0> and C<1>, and
		835	an I/O watcher at priority C<0>, then the idle watcher at priority C<1>
		836	and the I/O watcher will always run when ready. Only when the idle watcher
		837	at priority C<1> is stopped and the I/O watcher at priority C<0> is not
		838	pending with the C<0>-priority idle watcher be invoked.
		839
651	The C<idle_ns> variant doesn't start (activate) the newly created watcher.	840	The C<idle_ns> variant doesn't start (activate) the newly created watcher.
652		841
653	=back	842	=back
654		843
655		844
…		…
658	=over 4	847	=over 4
659		848
660	=item $w = EV::prepare $callback	849	=item $w = EV::prepare $callback
661		850
662	=item $w = EV::prepare_ns $callback	851	=item $w = EV::prepare_ns $callback
		852
		853	=item $w = $loop->prepare ($callback)
		854
		855	=item $w = $loop->prepare_ns ($callback)
663		856
664	Call the callback just before the process would block. You can still	857	Call the callback just before the process would block. You can still
665	create/modify any watchers at this point.	858	create/modify any watchers at this point.
666		859
667	See the EV::check watcher, below, for explanations and an example.	860	See the EV::check watcher, below, for explanations and an example.
…		…
676	=over 4	869	=over 4
677		870
678	=item $w = EV::check $callback	871	=item $w = EV::check $callback
679		872
680	=item $w = EV::check_ns $callback	873	=item $w = EV::check_ns $callback
		874
		875	=item $w = $loop->check ($callback)
		876
		877	=item $w = $loop->check_ns ($callback)
681		878
682	Call the callback just after the process wakes up again (after it has	879	Call the callback just after the process wakes up again (after it has
683	gathered events), but before any other callbacks have been invoked.	880	gathered events), but before any other callbacks have been invoked.
684		881
685	This is used to integrate other event-based software into the EV	882	This is used to integrate other event-based software into the EV
…		…
695	or return;	892	or return;
696		893
697	# make the dispatcher handle any outstanding stuff	894	# make the dispatcher handle any outstanding stuff
698	... not shown	895	... not shown
699		896
700	# create an IO watcher for each and every socket	897	# create an I/O watcher for each and every socket
701	@snmp_watcher = (	898	@snmp_watcher = (
702	(map { EV::io $_, EV::READ, sub { } }	899	(map { EV::io $_, EV::READ, sub { } }
703	keys %{ $dispatcher->{_descriptors} }),	900	keys %{ $dispatcher->{_descriptors} }),
704		901
705	EV::timer +($event->[Net::SNMP::Dispatcher::_ACTIVE]	902	EV::timer +($event->[Net::SNMP::Dispatcher::_ACTIVE]
…		…
740		937
741	=item $w = EV::fork $callback	938	=item $w = EV::fork $callback
742		939
743	=item $w = EV::fork_ns $callback	940	=item $w = EV::fork_ns $callback
744		941
		942	=item $w = $loop->fork ($callback)
		943
		944	=item $w = $loop->fork_ns ($callback)
		945
745	Call the callback before the event loop is resumed in the child process	946	Call the callback before the event loop is resumed in the child process
746	after a fork.	947	after a fork.
747		948
748	The C<fork_ns> variant doesn't start (activate) the newly created watcher.	949	The C<fork_ns> variant doesn't start (activate) the newly created watcher.
749		950
750	=back	951	=back
751		952
		953
		954	=head3 EMBED WATCHERS - when one backend isn't enough...
		955
		956	This is a rather advanced watcher type that lets you embed one event loop
		957	into another (currently only IO events are supported in the embedded
		958	loop, other types of watchers might be handled in a delayed or incorrect
		959	fashion and must not be used).
		960
		961	See the libev documentation at
		962	L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#code_ev_embed_code_when_one_backend_>
		963	(locally installed as F<EV::c_doc>) for more details.
		964
		965	In short, this watcher is most useful on BSD systems without working
		966	kqueue to still be able to handle a large number of sockets:
		967
		968	my $socket_loop;
		969
		970	# check wether we use SELECT or POLL _and_ KQUEUE is supported
		971	if (
		972	(EV::backend & (EV::BACKEND_POLL \| EV::BACKEND_SELECT))
		973	&& (EV::supported_backends & EV::embeddable_backends & EV::BACKEND_KQUEUE)
		974	) {
		975	# use kqueue for sockets
		976	$socket_loop = new EV::Loop EV::BACKEND_KQUEUE \| EV::FLAG_NOENV;
		977	}
		978
		979	# use the default loop otherwise
		980	$socket_loop \|\|= EV::default_loop;
		981
		982	=over 4
		983
		984	=item $w = EV::embed $otherloop[, $callback]
		985
		986	=item $w = EV::embed_ns $otherloop[, $callback]
		987
		988	=item $w = $loop->embed ($otherloop[, $callback])
		989
		990	=item $w = $loop->embed_ns ($otherloop[, $callback])
		991
		992	Call the callback when the embedded event loop (C<$otherloop>) has any
		993	I/O activity. The C<$callback> is optional: if it is missing, then the
		994	embedded event loop will be managed automatically (which is recommended),
		995	otherwise you have to invoke C<sweep> yourself.
		996
		997	The C<embed_ns> variant doesn't start (activate) the newly created watcher.
		998
		999	=back
		1000
		1001	=head3 ASYNC WATCHERS - how to wake up another event loop
		1002
		1003	Async watchers are provided by EV, but have little use in perl directly, as perl
		1004	neither supports threads nor direct access to signal handlers or other
		1005	contexts where they could be of value.
		1006
		1007	It is, however, possible to use them from the XS level.
		1008
		1009	Please see the libev documentation for further details.
		1010
		1011	=over 4
		1012
		1013	=item $w = EV::async $callback
		1014
		1015	=item $w = EV::async_ns $callback
		1016
		1017	=item $w->send
		1018
		1019	=item $bool = $w->async_pending
		1020
		1021	=back
		1022
		1023
		1024	=head1 PERL SIGNALS
		1025
		1026	While Perl signal handling (C<%SIG>) is not affected by EV, the behaviour
		1027	with EV is as the same as any other C library: Perl-signals will only be
		1028	handled when Perl runs, which means your signal handler might be invoked
		1029	only the next time an event callback is invoked.
		1030
		1031	The solution is to use EV signal watchers (see C<EV::signal>), which will
		1032	ensure proper operations with regards to other event watchers.
		1033
		1034	If you cannot do this for whatever reason, you can also force a watcher
		1035	to be called on every event loop iteration by installing a C<EV::check>
		1036	watcher:
		1037
		1038	my $async_check = EV::check sub { };
		1039
		1040	This ensures that perl gets into control for a short time to handle any
		1041	pending signals, and also ensures (slightly) slower overall operation.
752		1042
753	=head1 THREADS	1043	=head1 THREADS
754		1044
755	Threads are not supported by this module in any way. Perl pseudo-threads	1045	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	1046	is evil stuff and must die. As soon as Perl gains real threads I will work
…		…
778	our $DIED = sub {	1068	our $DIED = sub {
779	warn "EV: error in callback (ignoring): $@";	1069	warn "EV: error in callback (ignoring): $@";
780	};	1070	};
781		1071
782	default_loop	1072	default_loop
783	or die 'EV: cannot initialise libev backend. bad $ENV{LIBEV_METHODS}?';	1073	or die 'EV: cannot initialise libev backend. bad $ENV{LIBEV_FLAGS}?';
784		1074
785	1;	1075	1;
786		1076
787	=head1 SEE ALSO	1077	=head1 SEE ALSO
788		1078
789	L<EV::DNS>.	1079	L<EV::ADNS> (asynchronous DNS), L<Glib::EV> (makes Glib/Gtk2 use EV as
		1080	event loop), L<EV::Glib> (embed Glib into EV), L<Coro::EV> (efficient
		1081	coroutines with EV), L<Net::SNMP::EV> (asynchronous SNMP), L<AnyEvent> for
		1082	event-loop agnostic and portable event driven programming.
790		1083
791	=head1 AUTHOR	1084	=head1 AUTHOR
792		1085
793	Marc Lehmann <schmorp@schmorp.de>	1086	Marc Lehmann <schmorp@schmorp.de>
794	http://home.schmorp.de/	1087	http://home.schmorp.de/
795		1088
796	=cut	1089	=cut
797		1090

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Comparing EV/EV.pm (file contents): Revision 1.58 by root, Wed Nov 28 19:22:16 2007 UTC vs. Revision 1.104 by root, Thu Oct 2 12:26:25 2008 UTC

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Comparing EV/EV.pm (file contents):
Revision 1.58 by root, Wed Nov 28 19:22:16 2007 UTC vs.
Revision 1.104 by root, Thu Oct 2 12:26:25 2008 UTC