[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 1.125 by root, Thu Dec 31 06:59:47 2009 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::libev>) 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.
		72
		73	=head2 MODULE EXPORTS
		74
		75	This module does not export any symbols.
64		76
65	=cut	77	=cut
66		78
67	package EV;	79	package EV;
68		80
69	use strict;	81	use common::sense;
70		82
71	BEGIN {	83	BEGIN {
72	our $VERSION = '1.6';	84	our $VERSION = '3.9';
73	use XSLoader;	85	use XSLoader;
74	XSLoader::load "EV", $VERSION;	86	XSLoader::load "EV", $VERSION;
75	}	87	}
76		88
77	@EV::IO::ISA =	89	@EV::IO::ISA =
…		…
83	@EV::Idle::ISA =	95	@EV::Idle::ISA =
84	@EV::Prepare::ISA =	96	@EV::Prepare::ISA =
85	@EV::Check::ISA =	97	@EV::Check::ISA =
86	@EV::Embed::ISA =	98	@EV::Embed::ISA =
87	@EV::Fork::ISA =	99	@EV::Fork::ISA =
		100	@EV::Async::ISA =
88	"EV::Watcher";	101	"EV::Watcher";
89		102
		103	@EV::Loop::Default::ISA = "EV::Loop";
		104
		105	=head1 EVENT LOOPS
		106
		107	EV supports multiple event loops: There is a single "default event loop"
		108	that can handle everything including signals and child watchers, and any
		109	number of "dynamic event loops" that can use different backends (with
		110	various limitations), but no child and signal watchers.
		111
		112	You do not have to do anything to create the default event loop: When
		113	the module is loaded a suitable backend is selected on the premise of
		114	selecting a working backend (which for example rules out kqueue on most
		115	BSDs). Modules should, unless they have "special needs" always use the
		116	default loop as this is fastest (perl-wise), best supported by other
		117	modules (e.g. AnyEvent or Coro) and most portable event loop.
		118
		119	For specific programs you can create additional event loops dynamically.
		120
		121	If you want to take advantage of kqueue (which often works properly for
		122	sockets only) even though the default loop doesn't enable it, you can
		123	I<embed> a kqueue loop into the default loop: running the default loop
		124	will then also service the kqueue loop to some extent. See the example in
		125	the section about embed watchers for an example on how to achieve that.
		126
		127	=over 4
		128
		129	=item $loop = new EV::Loop [$flags]
		130
		131	Create a new event loop as per the specified flags. Please refer to
		132	the C<ev_loop_new ()> function description in the libev documentation
		133	(L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#GLOBAL_FUNCTIONS>,
		134	or locally-installed as F<EV::libev> manpage) for more info.
		135
		136	The loop will automatically be destroyed when it is no longer referenced
		137	by any watcher and the loop object goes out of scope.
		138
		139	If you are not embedding the loop, then Using C<EV::FLAG_FORKCHECK>
		140	is recommended, as only the default event loop is protected by this
		141	module. If you I<are> embedding this loop in the default loop, this is not
		142	necessary, as C<EV::embed> automatically does the right thing on fork.
		143
		144	=item $loop->loop_fork
		145
		146	Must be called after a fork in the child, before entering or continuing
		147	the event loop. An alternative is to use C<EV::FLAG_FORKCHECK> which calls
		148	this function automatically, at some performance loss (refer to the libev
		149	documentation).
		150
		151	=item $loop->loop_verify
		152
		153	Calls C<ev_verify> to make internal consistency checks (for debugging
		154	libev) and abort the program if any data structures were found to be
		155	corrupted.
		156
		157	=item $loop = EV::default_loop [$flags]
		158
		159	Return the default loop (which is a singleton object). Since this module
		160	already creates the default loop with default flags, specifying flags here
		161	will not have any effect unless you destroy the default loop first, which
		162	isn't supported. So in short: don't do it, and if you break it, you get to
		163	keep the pieces.
		164
		165	=back
		166
		167
90	=head1 BASIC INTERFACE	168	=head1 BASIC INTERFACE
91		169
92	=over 4	170	=over 4
93		171
94	=item $EV::DIED	172	=item $EV::DIED
95		173
96	Must contain a reference to a function that is called when a callback	174	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	175	throws an exception (with $@ containing the error). The default prints an
98	informative message and continues.	176	informative message and continues.
99		177
100	If this callback throws an exception it will be silently ignored.	178	If this callback throws an exception it will be silently ignored.
101		179
		180	=item $flags = EV::supported_backends
		181
		182	=item $flags = EV::recommended_backends
		183
		184	=item $flags = EV::embeddable_backends
		185
		186	Returns the set (see C<EV::BACKEND_*> flags) of backends supported by this
		187	instance of EV, the set of recommended backends (supposed to be good) for
		188	this platform and the set of embeddable backends (see EMBED WATCHERS).
		189
		190	=item EV::sleep $seconds
		191
		192	Block the process for the given number of (fractional) seconds.
		193
102	=item $time = EV::time	194	=item $time = EV::time
103		195
104	Returns the current time in (fractional) seconds since the epoch.	196	Returns the current time in (fractional) seconds since the epoch.
105		197
106	=item $time = EV::now	198	=item $time = EV::now
107		199
		200	=item $time = $loop->now
		201
108	Returns the time the last event loop iteration has been started. This	202	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	203	is the time that (relative) timers are based on, and referring to it is
110	usually faster then calling EV::time.	204	usually faster then calling EV::time.
111		205
112	=item $method = EV::method	206	=item EV::now_update
113		207
		208	=item $loop->now_update
		209
		210	Establishes the current time by querying the kernel, updating the time
		211	returned by C<EV::now> in the progress. This is a costly operation and
		212	is usually done automatically within C<EV::loop>.
		213
		214	This function is rarely useful, but when some event callback runs for a
		215	very long time without entering the event loop, updating libev's idea of
		216	the current time is a good idea.
		217
		218	=item EV::suspend
		219
		220	=item $loop->suspend
		221
		222	=item EV::resume
		223
		224	=item $loop->resume
		225
		226	These two functions suspend and resume a loop, for use when the loop is
		227	not used for a while and timeouts should not be processed.
		228
		229	A typical use case would be an interactive program such as a game: When
		230	the user presses C<^Z> to suspend the game and resumes it an hour later it
		231	would be best to handle timeouts as if no time had actually passed while
		232	the program was suspended. This can be achieved by calling C<suspend>
		233	in your C<SIGTSTP> handler, sending yourself a C<SIGSTOP> and calling
		234	C<resume> directly afterwards to resume timer processing.
		235
		236	Effectively, all C<timer> watchers will be delayed by the time spend
		237	between C<suspend> and C<resume>, and all C<periodic> watchers
		238	will be rescheduled (that is, they will lose any events that would have
		239	occured while suspended).
		240
		241	After calling C<suspend> you B<must not> call I<any> function on the given
		242	loop other than C<resume>, and you B<must not> call C<resume>
		243	without a previous call to C<suspend>.
		244
		245	Calling C<suspend>/C<resume> has the side effect of updating the event
		246	loop time (see C<now_update>).
		247
		248	=item $backend = EV::backend
		249
		250	=item $backend = $loop->backend
		251
114	Returns an integer describing the backend used by libev (EV::METHOD_SELECT	252	Returns an integer describing the backend used by libev (EV::BACKEND_SELECT
115	or EV::METHOD_EPOLL).	253	or EV::BACKEND_EPOLL).
116		254
117	=item EV::loop [$flags]	255	=item EV::loop [$flags]
		256
		257	=item $loop->loop ([$flags])
118		258
119	Begin checking for events and calling callbacks. It returns when a	259	Begin checking for events and calling callbacks. It returns when a
120	callback calls EV::unloop.	260	callback calls EV::unloop.
121		261
122	The $flags argument can be one of the following:	262	The $flags argument can be one of the following:
…		…
125	EV::LOOP_ONESHOT block at most once (wait, but do not loop)	265	EV::LOOP_ONESHOT block at most once (wait, but do not loop)
126	EV::LOOP_NONBLOCK do not block at all (fetch/handle events but do not wait)	266	EV::LOOP_NONBLOCK do not block at all (fetch/handle events but do not wait)
127		267
128	=item EV::unloop [$how]	268	=item EV::unloop [$how]
129		269
		270	=item $loop->unloop ([$how])
		271
130	When called with no arguments or an argument of EV::UNLOOP_ONE, makes the	272	When called with no arguments or an argument of EV::UNLOOP_ONE, makes the
131	innermost call to EV::loop return.	273	innermost call to EV::loop return.
132		274
133	When called with an argument of EV::UNLOOP_ALL, all calls to EV::loop will return as	275	When called with an argument of EV::UNLOOP_ALL, all calls to EV::loop will return as
134	fast as possible.	276	fast as possible.
135		277
136	=item $count = EV::loop_count	278	=item $count = EV::loop_count
137		279
		280	=item $count = $loop->loop_count
		281
138	Return the number of times the event loop has polled for new	282	Return the number of times the event loop has polled for new
139	events. Sometiems useful as a generation counter.	283	events. Sometimes useful as a generation counter.
140		284
141	=item EV::once $fh_or_undef, $events, $timeout, $cb->($revents)	285	=item EV::once $fh_or_undef, $events, $timeout, $cb->($revents)
		286
		287	=item $loop->once ($fh_or_undef, $events, $timeout, $cb->($revents))
142		288
143	This function rolls together an I/O and a timer watcher for a single	289	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.	290	one-shot event without the need for managing a watcher object.
145		291
146	If C<$fh_or_undef> is a filehandle or file descriptor, then C<$events>	292	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	298	If timeout is C<undef> or negative, then there will be no
153	timeout. Otherwise a EV::timer with this value will be started.	299	timeout. Otherwise a EV::timer with this value will be started.
154		300
155	When an error occurs or either the timeout or I/O watcher triggers, then	301	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	302	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>,	303	you can expect it to be a combination of C<EV::ERROR>, C<EV::READ>,
158	C<EV::WRITE> and C<EV::TIMEOUT>).	304	C<EV::WRITE> and C<EV::TIMEOUT>).
159		305
160	EV::once doesn't return anything: the watchers stay active till either	306	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	307	of them triggers, then they will be stopped and freed, and the callback
162	invoked.	308	invoked.
163		309
164	=back	310	=item EV::feed_fd_event ($fd, $revents)
165		311
		312	=item $loop->feed_fd_event ($fd, $revents)
		313
		314	Feed an event on a file descriptor into EV. EV will react to this call as
		315	if the readyness notifications specified by C<$revents> (a combination of
		316	C<EV::READ> and C<EV::WRITE>) happened on the file descriptor C<$fd>.
		317
		318	=item EV::feed_signal_event ($signal)
		319
		320	Feed a signal event into EV. EV will react to this call as if the signal
		321	specified by C<$signal> had occured.
		322
		323	=item EV::set_io_collect_interval $time
		324
		325	=item $loop->set_io_collect_interval ($time)
		326
		327	=item EV::set_timeout_collect_interval $time
		328
		329	=item $loop->set_timeout_collect_interval ($time)
		330
		331	These advanced functions set the minimum block interval when polling for I/O events and the minimum
		332	wait interval for timer events. See the libev documentation at
		333	L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#FUNCTIONS_CONTROLLING_THE_EVENT_LOOP>
		334	(locally installed as F<EV::libev>) for a more detailed discussion.
		335
		336	=item $count = EV::pending_count
		337
		338	=item $count = $loop->pending_count
		339
		340	Returns the number of currently pending watchers.
		341
		342	=item EV::invoke_pending
		343
		344	=item $loop->invoke_pending
		345
		346	Invoke all currently pending watchers.
		347
		348	=back
		349
		350
166	=head2 WATCHER OBJECTS	351	=head1 WATCHER OBJECTS
167		352
168	A watcher is an object that gets created to record your interest in some	353	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	354	event. For instance, if you want to wait for STDIN to become readable, you
170	would create an EV::io watcher for that:	355	would create an EV::io watcher for that:
171		356
172	my $watcher = EV::io *STDIN, EV::READ, sub {	357	my $watcher = EV::io *STDIN, EV::READ, sub {
173	my ($watcher, $revents) = @_;	358	my ($watcher, $revents) = @_;
174	warn "yeah, STDIN should not be readable without blocking!\n"	359	warn "yeah, STDIN should now be readable without blocking!\n"
175	};	360	};
176		361
177	All watchers can be active (waiting for events) or inactive (paused). Only	362	All watchers can be active (waiting for events) or inactive (paused). Only
178	active watchers will have their callbacks invoked. All callbacks will be	363	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	364	called with at least two arguments: the watcher and a bitmask of received
180	events.	365	events.
181		366
182	Each watcher type has its associated bit in revents, so you can use the	367	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	368	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,	369	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	370	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	371	(which can set both EV::READ and EV::WRITE bits), and EV::timer (which
187	uses EV::TIMEOUT).	372	uses EV::TIMEOUT).
188		373
189	In the rare case where one wants to create a watcher but not start it at	374	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	375	the same time, each constructor has a variant with a trailing C<_ns> in
…		…
212		397
213	=item $w->stop	398	=item $w->stop
214		399
215	Stop a watcher if it is active. Also clear any pending events (events that	400	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),	401	have been received but that didn't yet result in a callback invocation),
217	regardless of wether the watcher was active or not.	402	regardless of whether the watcher was active or not.
218		403
219	=item $bool = $w->is_active	404	=item $bool = $w->is_active
220		405
221	Returns true if the watcher is active, false otherwise.	406	Returns true if the watcher is active, false otherwise.
222		407
…		…
252	The default priority of any newly-created watcher is 0.	437	The default priority of any newly-created watcher is 0.
253		438
254	Note that the priority semantics have not yet been fleshed out and are	439	Note that the priority semantics have not yet been fleshed out and are
255	subject to almost certain change.	440	subject to almost certain change.
256		441
257	=item $w->trigger ($revents)	442	=item $w->invoke ($revents)
258		443
259	Call the callback now with the given event mask.	444	Call the callback now with the given event mask.
		445
		446	=item $w->feed_event ($revents)
		447
		448	Feed some events on this watcher into EV. EV will react to this call as if
		449	the watcher had received the given C<$revents> mask.
		450
		451	=item $revents = $w->clear_pending
		452
		453	If the watcher is pending, this function clears its pending status and
		454	returns its C<$revents> bitset (as if its callback was invoked). If the
		455	watcher isn't pending it does nothing and returns C<0>.
260		456
261	=item $previous_state = $w->keepalive ($bool)	457	=item $previous_state = $w->keepalive ($bool)
262		458
263	Normally, C<EV::loop> will return when there are no active watchers	459	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	460	(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),	461	convenient 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	462	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 :).	463	finished (or they forgot to register some watchers for their task :).
268		464
269	Sometimes, however, this gets in your way, for example when you the module	465	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	466	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	467	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	468	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	469	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.	470	because you happen to have this long-running UDP port watcher.
275		471
276	In this case you can clear the keepalive status, which means that even	472	In this case you can clear the keepalive status, which means that even
277	though your watcher is active, it won't keep C<EV::loop> from returning.	473	though your watcher is active, it won't keep C<EV::loop> from returning.
278		474
279	The initial value for keepalive is true (enabled), and you cna change it	475	The initial value for keepalive is true (enabled), and you can change it
280	any time.	476	any time.
281		477
282	Example: Register an IO watcher for some UDP socket but do not keep the	478	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.	479	event loop from running just because of that watcher.
284		480
285	my $udp_socket = ...	481	my $udp_socket = ...
286	my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... };	482	my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... };
287	$udp_watcher->keepalive (0);	483	$udp_watcher->keepalive (0);
288		484
289	=back	485	=item $loop = $w->loop
290		486
		487	Return the loop that this watcher is attached to.
291		488
		489	=back
		490
		491
292	=head2 WATCHER TYPES	492	=head1 WATCHER TYPES
293		493
294	Each of the following subsections describes a single watcher type.	494	Each of the following subsections describes a single watcher type.
295		495
296	=head3 IO WATCHERS - is this file descriptor readable or writable?	496	=head3 I/O WATCHERS - is this file descriptor readable or writable?
297		497
298	=over 4	498	=over 4
299		499
300	=item $w = EV::io $fileno_or_fh, $eventmask, $callback	500	=item $w = EV::io $fileno_or_fh, $eventmask, $callback
301		501
302	=item $w = EV::io_ns $fileno_or_fh, $eventmask, $callback	502	=item $w = EV::io_ns $fileno_or_fh, $eventmask, $callback
		503
		504	=item $w = $loop->io ($fileno_or_fh, $eventmask, $callback)
		505
		506	=item $w = $loop->io_ns ($fileno_or_fh, $eventmask, $callback)
303		507
304	As long as the returned watcher object is alive, call the C<$callback>	508	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.	509	when at least one of events specified in C<$eventmask> occurs.
306		510
307	The $eventmask can be one or more of these constants ORed together:	511	The $eventmask can be one or more of these constants ORed together:
…		…
336	=over 4	540	=over 4
337		541
338	=item $w = EV::timer $after, $repeat, $callback	542	=item $w = EV::timer $after, $repeat, $callback
339		543
340	=item $w = EV::timer_ns $after, $repeat, $callback	544	=item $w = EV::timer_ns $after, $repeat, $callback
		545
		546	=item $w = $loop->timer ($after, $repeat, $callback)
		547
		548	=item $w = $loop->timer_ns ($after, $repeat, $callback)
341		549
342	Calls the callback after C<$after> seconds (which may be fractional). If	550	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 $repeat	551	C<$repeat> is non-zero, the timer will be restarted (with the $repeat
344	value as $after) after the callback returns.	552	value as $after) after the callback returns.
345		553
…		…
386	=over 4	594	=over 4
387		595
388	=item $w = EV::periodic $at, $interval, $reschedule_cb, $callback	596	=item $w = EV::periodic $at, $interval, $reschedule_cb, $callback
389		597
390	=item $w = EV::periodic_ns $at, $interval, $reschedule_cb, $callback	598	=item $w = EV::periodic_ns $at, $interval, $reschedule_cb, $callback
		599
		600	=item $w = $loop->periodic ($at, $interval, $reschedule_cb, $callback)
		601
		602	=item $w = $loop->periodic_ns ($at, $interval, $reschedule_cb, $callback)
391		603
392	Similar to EV::timer, but is not based on relative timeouts but on	604	Similar to EV::timer, but is not based on relative timeouts but on
393	absolute times. Apart from creating "simple" timers that trigger "at" the	605	absolute times. Apart from creating "simple" timers that trigger "at" the
394	specified time, it can also be used for non-drifting absolute timers and	606	specified time, it can also be used for non-drifting absolute timers and
395	more complex, cron-like, setups that are not adversely affected by time	607	more complex, cron-like, setups that are not adversely affected by time
…		…
405	This time simply fires at the wallclock time C<$at> and doesn't repeat. It	617	This time simply fires at the wallclock time C<$at> and doesn't repeat. It
406	will not adjust when a time jump occurs, that is, if it is to be run	618	will not adjust when a time jump occurs, that is, if it is to be run
407	at January 1st 2011 then it will run when the system time reaches or	619	at January 1st 2011 then it will run when the system time reaches or
408	surpasses this time.	620	surpasses this time.
409		621
410	=item * non-repeating interval timer ($interval > 0, $reschedule_cb = 0)	622	=item * repeating interval timer ($interval > 0, $reschedule_cb = 0)
411		623
412	In this mode the watcher will always be scheduled to time out at the	624	In this mode the watcher will always be scheduled to time out at the
413	next C<$at + N * $interval> time (for some integer N) and then repeat,	625	next C<$at + N * $interval> time (for some integer N) and then repeat,
414	regardless of any time jumps.	626	regardless of any time jumps.
415		627
…		…
433	time the periodic watcher gets scheduled, the reschedule callback	645	time the periodic watcher gets scheduled, the reschedule callback
434	($reschedule_cb) will be called with the watcher as first, and the current	646	($reschedule_cb) will be called with the watcher as first, and the current
435	time as second argument.	647	time as second argument.
436		648
437	I<This callback MUST NOT stop or destroy this or any other periodic	649	I<This callback MUST NOT stop or destroy this or any other periodic
438	watcher, ever>. If you need to stop it, return 1e30 and stop it	650	watcher, ever, and MUST NOT call any event loop functions or methods>. If
439	afterwards.	651	you need to stop it, return 1e30 and stop it afterwards. You may create
		652	and start a C<EV::prepare> watcher for this task.
440		653
441	It must return the next time to trigger, based on the passed time value	654	It must return the next time to trigger, based on the passed time value
442	(that is, the lowest time value larger than to the second argument). It	655	(that is, the lowest time value larger than or equal to to the second
443	will usually be called just before the callback will be triggered, but	656	argument). It will usually be called just before the callback will be
444	might be called at other times, too.	657	triggered, but might be called at other times, too.
445		658
446	This can be used to create very complex timers, such as a timer that	659	This can be used to create very complex timers, such as a timer that
447	triggers on each midnight, local time (actually 24 hours after the last	660	triggers on each midnight, local time (actually 24 hours after the last
448	midnight, to keep the example simple. If you know a way to do it correctly	661	midnight, to keep the example simple. If you know a way to do it correctly
449	in about the same space (without requiring elaborate modules), drop me a	662	in about the same space (without requiring elaborate modules), drop me a
…		…
470		683
471	=item $w->again	684	=item $w->again
472		685
473	Simply stops and starts the watcher again.	686	Simply stops and starts the watcher again.
474		687
		688	=item $time = $w->at
		689
		690	Return the time that the watcher is expected to trigger next.
		691
475	=back	692	=back
476		693
477		694
478	=head3 SIGNAL WATCHERS - signal me when a signal gets signalled!	695	=head3 SIGNAL WATCHERS - signal me when a signal gets signalled!
479		696
480	=over 4	697	=over 4
481		698
482	=item $w = EV::signal $signal, $callback	699	=item $w = EV::signal $signal, $callback
483		700
484	=item $w = EV::signal_ns $signal, $callback	701	=item $w = EV::signal_ns $signal, $callback
		702
		703	=item $w = $loop->signal ($signal, $callback)
		704
		705	=item $w = $loop->signal_ns ($signal, $callback)
485		706
486	Call the callback when $signal is received (the signal can be specified by	707	Call the callback when $signal is received (the signal can be specified by
487	number or by name, just as with C<kill> or C<%SIG>).	708	number or by name, just as with C<kill> or C<%SIG>).
		709
		710	Only one event loop can grab a given signal - attempting to grab the same
		711	signal from two EV loops will crash the program immediately or cause data
		712	corruption.
488		713
489	EV will grab the signal for the process (the kernel only allows one	714	EV will grab the signal for the process (the kernel only allows one
490	component to receive a signal at a time) when you start a signal watcher,	715	component to receive a signal at a time) when you start a signal watcher,
491	and removes it again when you stop it. Perl does the same when you	716	and removes it again when you stop it. Perl does the same when you
492	add/remove callbacks to C<%SIG>, so watch out.	717	add/remove callbacks to C<%SIG>, so watch out.
…		…
512		737
513	=head3 CHILD WATCHERS - watch out for process status changes	738	=head3 CHILD WATCHERS - watch out for process status changes
514		739
515	=over 4	740	=over 4
516		741
517	=item $w = EV::child $pid, $callback	742	=item $w = EV::child $pid, $trace, $callback
518		743
519	=item $w = EV::child_ns $pid, $callback	744	=item $w = EV::child_ns $pid, $trace, $callback
520		745
		746	=item $w = $loop->child ($pid, $trace, $callback)
		747
		748	=item $w = $loop->child_ns ($pid, $trace, $callback)
		749
521	Call the callback when a status change for pid C<$pid> (or any pid if	750	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	751	if C<$pid> is 0) has been received (a status change happens when the
		752	process terminates or is killed, or, when trace is true, additionally when
		753	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	754	a C<SIGCHLD>, EV will fetch the outstanding exit/wait status for all
524	changed/zombie children and call the callback.	755	changed/zombie children and call the callback.
525		756
526	It is valid (and fully supported) to install a child watcher after a child	757	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	758	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	765	You can have as many pid watchers per pid as you want, they will all be
535	called.	766	called.
536		767
537	The C<child_ns> variant doesn't start (activate) the newly created watcher.	768	The C<child_ns> variant doesn't start (activate) the newly created watcher.
538		769
539	=item $w->set ($pid)	770	=item $w->set ($pid, $trace)
540		771
541	Reconfigures the watcher, see the constructor above for details. Can be called at	772	Reconfigures the watcher, see the constructor above for details. Can be called at
542	any time.	773	any time.
543		774
544	=item $current_pid = $w->pid	775	=item $current_pid = $w->pid
545		776
546	=item $old_pid = $w->pid ($new_pid)
547
548	Returns the previously set process id and optionally set a new one.	777	Returns the previously set process id and optionally set a new one.
549		778
550	=item $exit_status = $w->rstatus	779	=item $exit_status = $w->rstatus
551		780
552	Return the exit/wait status (as returned by waitpid, see the waitpid entry	781	Return the exit/wait status (as returned by waitpid, see the waitpid entry
…		…
565	=over 4	794	=over 4
566		795
567	=item $w = EV::stat $path, $interval, $callback	796	=item $w = EV::stat $path, $interval, $callback
568		797
569	=item $w = EV::stat_ns $path, $interval, $callback	798	=item $w = EV::stat_ns $path, $interval, $callback
		799
		800	=item $w = $loop->stat ($path, $interval, $callback)
		801
		802	=item $w = $loop->stat_ns ($path, $interval, $callback)
570		803
571	Call the callback when a file status change has been detected on	804	Call the callback when a file status change has been detected on
572	C<$path>. The C<$path> does not need to exist, changing from "path exists"	805	C<$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.	806	to "path does not exist" is a status change like any other.
574		807
…		…
645		878
646	=item $w = EV::idle $callback	879	=item $w = EV::idle $callback
647		880
648	=item $w = EV::idle_ns $callback	881	=item $w = EV::idle_ns $callback
649		882
650	Call the callback when there are no pending io, timer/periodic, signal or	883	=item $w = $loop->idle ($callback)
651	child events, i.e. when the process is idle.	884
		885	=item $w = $loop->idle_ns ($callback)
		886
		887	Call the callback when there are no other pending watchers of the same or
		888	higher priority (excluding check, prepare and other idle watchers of the
		889	same or lower priority, of course). They are called idle watchers because
		890	when the watcher is the highest priority pending event in the process, the
		891	process is considered to be idle at that priority.
		892
		893	If you want a watcher that is only ever called when I<no> other events are
		894	outstanding you have to set the priority to C<EV::MINPRI>.
652		895
653	The process will not block as long as any idle watchers are active, and	896	The process will not block as long as any idle watchers are active, and
654	they will be called repeatedly until stopped.	897	they will be called repeatedly until stopped.
655		898
		899	For example, if you have idle watchers at priority C<0> and C<1>, and
		900	an I/O watcher at priority C<0>, then the idle watcher at priority C<1>
		901	and the I/O watcher will always run when ready. Only when the idle watcher
		902	at priority C<1> is stopped and the I/O watcher at priority C<0> is not
		903	pending with the C<0>-priority idle watcher be invoked.
		904
656	The C<idle_ns> variant doesn't start (activate) the newly created watcher.	905	The C<idle_ns> variant doesn't start (activate) the newly created watcher.
657		906
658	=back	907	=back
659		908
660		909
…		…
663	=over 4	912	=over 4
664		913
665	=item $w = EV::prepare $callback	914	=item $w = EV::prepare $callback
666		915
667	=item $w = EV::prepare_ns $callback	916	=item $w = EV::prepare_ns $callback
		917
		918	=item $w = $loop->prepare ($callback)
		919
		920	=item $w = $loop->prepare_ns ($callback)
668		921
669	Call the callback just before the process would block. You can still	922	Call the callback just before the process would block. You can still
670	create/modify any watchers at this point.	923	create/modify any watchers at this point.
671		924
672	See the EV::check watcher, below, for explanations and an example.	925	See the EV::check watcher, below, for explanations and an example.
…		…
681	=over 4	934	=over 4
682		935
683	=item $w = EV::check $callback	936	=item $w = EV::check $callback
684		937
685	=item $w = EV::check_ns $callback	938	=item $w = EV::check_ns $callback
		939
		940	=item $w = $loop->check ($callback)
		941
		942	=item $w = $loop->check_ns ($callback)
686		943
687	Call the callback just after the process wakes up again (after it has	944	Call the callback just after the process wakes up again (after it has
688	gathered events), but before any other callbacks have been invoked.	945	gathered events), but before any other callbacks have been invoked.
689		946
690	This is used to integrate other event-based software into the EV	947	This is used to integrate other event-based software into the EV
…		…
700	or return;	957	or return;
701		958
702	# make the dispatcher handle any outstanding stuff	959	# make the dispatcher handle any outstanding stuff
703	... not shown	960	... not shown
704		961
705	# create an IO watcher for each and every socket	962	# create an I/O watcher for each and every socket
706	@snmp_watcher = (	963	@snmp_watcher = (
707	(map { EV::io $_, EV::READ, sub { } }	964	(map { EV::io $_, EV::READ, sub { } }
708	keys %{ $dispatcher->{_descriptors} }),	965	keys %{ $dispatcher->{_descriptors} }),
709		966
710	EV::timer +($event->[Net::SNMP::Dispatcher::_ACTIVE]	967	EV::timer +($event->[Net::SNMP::Dispatcher::_ACTIVE]
…		…
725	# make the dispatcher handle any new stuff	982	# make the dispatcher handle any new stuff
726	... not shown	983	... not shown
727	};	984	};
728		985
729	The callbacks of the created watchers will not be called as the watchers	986	The callbacks of the created watchers will not be called as the watchers
730	are destroyed before this cna happen (remember EV::check gets called	987	are destroyed before this can happen (remember EV::check gets called
731	first).	988	first).
732		989
733	The C<check_ns> variant doesn't start (activate) the newly created watcher.	990	The C<check_ns> variant doesn't start (activate) the newly created watcher.
734		991
735	=back	992	=back
…		…
745		1002
746	=item $w = EV::fork $callback	1003	=item $w = EV::fork $callback
747		1004
748	=item $w = EV::fork_ns $callback	1005	=item $w = EV::fork_ns $callback
749		1006
		1007	=item $w = $loop->fork ($callback)
		1008
		1009	=item $w = $loop->fork_ns ($callback)
		1010
750	Call the callback before the event loop is resumed in the child process	1011	Call the callback before the event loop is resumed in the child process
751	after a fork.	1012	after a fork.
752		1013
753	The C<fork_ns> variant doesn't start (activate) the newly created watcher.	1014	The C<fork_ns> variant doesn't start (activate) the newly created watcher.
		1015
		1016	=back
		1017
		1018
		1019	=head3 EMBED WATCHERS - when one backend isn't enough...
		1020
		1021	This is a rather advanced watcher type that lets you embed one event loop
		1022	into another (currently only IO events are supported in the embedded
		1023	loop, other types of watchers might be handled in a delayed or incorrect
		1024	fashion and must not be used).
		1025
		1026	See the libev documentation at
		1027	L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#code_ev_embed_code_when_one_backend_>
		1028	(locally installed as F<EV::libev>) for more details.
		1029
		1030	In short, this watcher is most useful on BSD systems without working
		1031	kqueue to still be able to handle a large number of sockets:
		1032
		1033	my $socket_loop;
		1034
		1035	# check wether we use SELECT or POLL _and_ KQUEUE is supported
		1036	if (
		1037	(EV::backend & (EV::BACKEND_POLL \| EV::BACKEND_SELECT))
		1038	&& (EV::supported_backends & EV::embeddable_backends & EV::BACKEND_KQUEUE)
		1039	) {
		1040	# use kqueue for sockets
		1041	$socket_loop = new EV::Loop EV::BACKEND_KQUEUE \| EV::FLAG_NOENV;
		1042	}
		1043
		1044	# use the default loop otherwise
		1045	$socket_loop \|\|= EV::default_loop;
		1046
		1047	=over 4
		1048
		1049	=item $w = EV::embed $otherloop[, $callback]
		1050
		1051	=item $w = EV::embed_ns $otherloop[, $callback]
		1052
		1053	=item $w = $loop->embed ($otherloop[, $callback])
		1054
		1055	=item $w = $loop->embed_ns ($otherloop[, $callback])
		1056
		1057	Call the callback when the embedded event loop (C<$otherloop>) has any
		1058	I/O activity. The C<$callback> is optional: if it is missing, then the
		1059	embedded event loop will be managed automatically (which is recommended),
		1060	otherwise you have to invoke C<sweep> yourself.
		1061
		1062	The C<embed_ns> variant doesn't start (activate) the newly created watcher.
		1063
		1064	=back
		1065
		1066	=head3 ASYNC WATCHERS - how to wake up another event loop
		1067
		1068	Async watchers are provided by EV, but have little use in perl directly,
		1069	as perl neither supports threads running in parallel nor direct access to
		1070	signal handlers or other contexts where they could be of value.
		1071
		1072	It is, however, possible to use them from the XS level.
		1073
		1074	Please see the libev documentation for further details.
		1075
		1076	=over 4
		1077
		1078	=item $w = EV::async $callback
		1079
		1080	=item $w = EV::async_ns $callback
		1081
		1082	=item $w->send
		1083
		1084	=item $bool = $w->async_pending
754		1085
755	=back	1086	=back
756		1087
757		1088
758	=head1 PERL SIGNALS	1089	=head1 PERL SIGNALS
…		…
769	to be called on every event loop iteration by installing a C<EV::check>	1100	to be called on every event loop iteration by installing a C<EV::check>
770	watcher:	1101	watcher:
771		1102
772	my $async_check = EV::check sub { };	1103	my $async_check = EV::check sub { };
773		1104
774	This ensures that perl shortly gets into control for a short time, and	1105	This ensures that perl gets into control for a short time to handle any
775	also ensures slower overall operation.	1106	pending signals, and also ensures (slightly) slower overall operation.
776		1107
777	=head1 THREADS	1108	=head1 ITHREADS
778		1109
779	Threads are not supported by this module in any way. Perl pseudo-threads	1110	Ithreads 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	1111	is evil stuff and must die. Real threads as provided by Coro are fully
781	on thread support for it.	1112	supported (and enhanced support is available via L<Coro::EV>).
782		1113
783	=head1 FORK	1114	=head1 FORK
784		1115
785	Most of the "improved" event delivering mechanisms of modern operating	1116	Most of the "improved" event delivering mechanisms of modern operating
786	systems have quite a few problems with fork(2) (to put it bluntly: it is	1117	systems have quite a few problems with fork(2) (to put it bluntly: it is
…		…
802	our $DIED = sub {	1133	our $DIED = sub {
803	warn "EV: error in callback (ignoring): $@";	1134	warn "EV: error in callback (ignoring): $@";
804	};	1135	};
805		1136
806	default_loop	1137	default_loop
807	or die 'EV: cannot initialise libev backend. bad $ENV{LIBEV_METHODS}?';	1138	or die 'EV: cannot initialise libev backend. bad $ENV{LIBEV_FLAGS}?';
808		1139
809	1;	1140	1;
810		1141
811	=head1 SEE ALSO	1142	=head1 SEE ALSO
812		1143
813	L<EV::ADNS> (asynchronous dns), L<Glib::EV> (makes Glib/Gtk2 use EV as	1144	L<EV::ADNS> (asynchronous DNS), L<Glib::EV> (makes Glib/Gtk2 use EV as
814	event loop), L<Coro::EV> (efficient coroutines with EV).	1145	event loop), L<EV::Glib> (embed Glib into EV), L<Coro::EV> (efficient
		1146	coroutines with EV), L<Net::SNMP::EV> (asynchronous SNMP), L<AnyEvent> for
		1147	event-loop agnostic and portable event driven programming.
815		1148
816	=head1 AUTHOR	1149	=head1 AUTHOR
817		1150
818	Marc Lehmann <schmorp@schmorp.de>	1151	Marc Lehmann <schmorp@schmorp.de>
819	http://home.schmorp.de/	1152	http://home.schmorp.de/
820		1153
821	=cut	1154	=cut
822		1155

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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 1.125 by root, Thu Dec 31 06:59:47 2009 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 1.125 by root, Thu Dec 31 06:59:47 2009 UTC