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

Comparing EV/EV.pm (file contents):
Revision 1.20 by root, Thu Nov 1 17:17:32 2007 UTC vs.
Revision 1.99 by root, Tue Jul 8 09:37:37 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 {	45	# STAT CHANGES
12	warn "is called after 2s";	46	my $w = EV::stat "/etc/passwd", 10, sub {
		47	my ($w, $revents) = @_;
		48	warn $w->path, " has changed somehow.\n";
13	};	49	};
14		50
15	my $w = EV::timer 2, 1, sub {
16	warn "is called roughly every 2s (repeat = 1)";
17	};
18
19	undef $w; # destroy event watcher again
20
21	my $w = EV::periodic 0, 60, 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 get the watcher object 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	my $w = EV::signal 3, sub {
39	warn "sigquit received (this is GNU/Linux, right?)\n";
40	};
41
42	# CHILD/PID STATUS CHANGES
43
44	my $w = EV::child 666, sub {
45	my ($w, $revents, $status) = @_;
46	};
47
48	# MAINLOOP	51	# MAINLOOP
49	EV::loop; # loop until EV::loop_done is called	52	EV::loop; # loop until EV::unloop is called or all watchers stop
50	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
51	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
52		55
53	=head1 DESCRIPTION	56	=head1 DESCRIPTION
54		57
55	This module provides an interface to libev	58	This module provides an interface to libev
56	(L<http://software.schmorp.de/pkg/libev.html>).	59	(L<http://software.schmorp.de/pkg/libev.html>). While the documentation
		60	below is comprehensive, one might also consult the documentation of libev
		61	itself (L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod>) for more
		62	subtle details on watcher semantics or some discussion on the available
		63	backends, or how to force a specific backend with C<LIBEV_FLAGS>, or just
		64	about in any case because it has much more detailed information.
		65
		66	This module is very fast and scalable. It is actually so fast that you
		67	can use it through the L<AnyEvent> module, stay portable to other event
		68	loops (if you don't rely on any watcher types not available through it)
		69	and still be faster than with any other event loop currently supported in
		70	Perl.
57		71
58	=cut	72	=cut
59		73
60	package EV;	74	package EV;
61		75
62	use strict;	76	use strict;
63		77
64	BEGIN {	78	BEGIN {
65	our $VERSION = '0.1';	79	our $VERSION = '3.42';
66	use XSLoader;	80	use XSLoader;
67	XSLoader::load "EV", $VERSION;	81	XSLoader::load "EV", $VERSION;
68	}	82	}
69		83
70	@EV::Io::ISA =	84	@EV::IO::ISA =
71	@EV::Timer::ISA =	85	@EV::Timer::ISA =
72	@EV::Periodic::ISA =	86	@EV::Periodic::ISA =
73	@EV::Signal::ISA =	87	@EV::Signal::ISA =
		88	@EV::Child::ISA =
		89	@EV::Stat::ISA =
74	@EV::Idle::ISA =	90	@EV::Idle::ISA =
75	@EV::Prepare::ISA =	91	@EV::Prepare::ISA =
76	@EV::Check::ISA =	92	@EV::Check::ISA =
77	@EV::Child::ISA = "EV::Watcher";	93	@EV::Embed::ISA =
		94	@EV::Fork::ISA =
		95	@EV::Async::ISA =
		96	"EV::Watcher";
		97
		98	@EV::Loop::Default::ISA = "EV::Loop";
		99
		100	=head1 EVENT LOOPS
		101
		102	EV supports multiple event loops: There is a single "default event loop"
		103	that can handle everything including signals and child watchers, and any
		104	number of "dynamic event loops" that can use different backends (with
		105	various limitations), but no child and signal watchers.
		106
		107	You do not have to do anything to create the default event loop: When
		108	the module is loaded a suitable backend is selected on the premise of
		109	selecting a working backend (which for example rules out kqueue on most
		110	BSDs). Modules should, unless they have "special needs" always use the
		111	default loop as this is fastest (perl-wise), best supported by other
		112	modules (e.g. AnyEvent or Coro) and most portable event loop.
		113
		114	For specific programs you can create additional event loops dynamically.
		115
		116	If you want to take avdantage of kqueue (which often works properly for
		117	sockets only) even though the default loop doesn't enable it, you can
		118	I<embed> a kqueue loop into the default loop: running the default loop
		119	will then also service the kqueue loop to some extent. See the example in
		120	the section about embed watchers for an example on how to achieve that.
		121
		122	=over 4
		123
		124	=item $loop = new EV::loop [$flags]
		125
		126	Create a new event loop as per the specified flags. Please refer to the
		127	C<ev_loop_new ()> function description in the libev documentation
		128	(L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#GLOBAL_FUNCTIONS>)
		129	for more info.
		130
		131	The loop will automatically be destroyed when it is no longer referenced
		132	by any watcher and the loop object goes out of scope.
		133
		134	Using C<EV::FLAG_FORKCHECK> is recommended, as only the default event loop
		135	is protected by this module.
		136
		137	=item $loop->loop_fork
		138
		139	Must be called after a fork in the child, before entering or continuing
		140	the event loop. An alternative is to use C<EV::FLAG_FORKCHECK> which calls
		141	this function automatically, at some performance loss (refer to the libev
		142	documentation).
		143
		144	=item $loop->loop_verify
		145
		146	Calls C<ev_verify> to make internal consistency checks (for debugging
		147	libev) and abort the program if any data structures were found to be
		148	corrupted.
		149
		150	=item $loop = EV::default_loop [$flags]
		151
		152	Return the default loop (which is a singleton object). Since this module
		153	already creates the default loop with default flags, specifying flags here
		154	will not have any effect unless you destroy the default loop first, which
		155	isn't supported. So in short: don't do it, and if you break it, you get to
		156	keep the pieces.
		157
		158	=back
		159
78		160
79	=head1 BASIC INTERFACE	161	=head1 BASIC INTERFACE
80		162
81	=over 4	163	=over 4
82		164
83	=item $EV::DIED	165	=item $EV::DIED
84		166
85	Must contain a reference to a function that is called when a callback	167	Must contain a reference to a function that is called when a callback
86	throws an exception (with $@ containing thr error). The default prints an	168	throws an exception (with $@ containing the error). The default prints an
87	informative message and continues.	169	informative message and continues.
88		170
89	If this callback throws an exception it will be silently ignored.	171	If this callback throws an exception it will be silently ignored.
90		172
		173	=item $flags = EV::supported_backends
		174
		175	=item $flags = EV::recommended_backends
		176
		177	=item $flags = EV::embeddable_backends
		178
		179	Returns the set (see C<EV::BACKEND_*> flags) of backends supported by this
		180	instance of EV, the set of recommended backends (supposed to be good) for
		181	this platform and the set of embeddable backends (see EMBED WATCHERS).
		182
		183	=item EV::sleep $seconds
		184
		185	Block the process for the given number of (fractional) seconds.
		186
91	=item $time = EV::time	187	=item $time = EV::time
92		188
93	Returns the current time in (fractional) seconds since the epoch.	189	Returns the current time in (fractional) seconds since the epoch.
94		190
95	=item $time = EV::now	191	=item $time = EV::now
		192
		193	=item $time = $loop->now
96		194
97	Returns the time the last event loop iteration has been started. This	195	Returns the time the last event loop iteration has been started. This
98	is the time that (relative) timers are based on, and refering to it is	196	is the time that (relative) timers are based on, and refering to it is
99	usually faster then calling EV::time.	197	usually faster then calling EV::time.
100		198
101	=item $method = EV::ev_method	199	=item $backend = EV::backend
		200
		201	=item $backend = $loop->backend
102		202
103	Returns an integer describing the backend used by libev (EV::METHOD_SELECT	203	Returns an integer describing the backend used by libev (EV::METHOD_SELECT
104	or EV::METHOD_EPOLL).	204	or EV::METHOD_EPOLL).
105		205
106	=item EV::loop [$flags]	206	=item EV::loop [$flags]
107		207
		208	=item $loop->loop ([$flags])
		209
108	Begin checking for events and calling callbacks. It returns when a	210	Begin checking for events and calling callbacks. It returns when a
109	callback calls EV::loop_done.	211	callback calls EV::unloop.
110		212
111	The $flags argument can be one of the following:	213	The $flags argument can be one of the following:
112		214
113	0 as above	215	0 as above
114	EV::LOOP_ONESHOT block at most once (wait, but do not loop)	216	EV::LOOP_ONESHOT block at most once (wait, but do not loop)
115	EV::LOOP_NONBLOCK do not block at all (fetch/handle events but do not wait)	217	EV::LOOP_NONBLOCK do not block at all (fetch/handle events but do not wait)
116		218
117	=item EV::loop_done [$how]	219	=item EV::unloop [$how]
118		220
		221	=item $loop->unloop ([$how])
		222
119	When called with no arguments or an argument of 1, makes the innermost	223	When called with no arguments or an argument of EV::UNLOOP_ONE, makes the
120	call to EV::loop return.	224	innermost call to EV::loop return.
121		225
122	When called with an agrument of 2, all calls to EV::loop will return as	226	When called with an argument of EV::UNLOOP_ALL, all calls to EV::loop will return as
123	fast as possible.	227	fast as possible.
124		228
125	=back	229	=item $count = EV::loop_count
126		230
127	=head2 WATCHER	231	=item $count = $loop->loop_count
		232
		233	Return the number of times the event loop has polled for new
		234	events. Sometiems useful as a generation counter.
		235
		236	=item EV::once $fh_or_undef, $events, $timeout, $cb->($revents)
		237
		238	=item $loop->once ($fh_or_undef, $events, $timeout, $cb->($revents))
		239
		240	This function rolls together an I/O and a timer watcher for a single
		241	one-shot event without the need for managing a watcher object.
		242
		243	If C<$fh_or_undef> is a filehandle or file descriptor, then C<$events>
		244	must be a bitset containing either C<EV::READ>, C<EV::WRITE> or C<EV::READ
		245	\| EV::WRITE>, indicating the type of I/O event you want to wait for. If
		246	you do not want to wait for some I/O event, specify C<undef> for
		247	C<$fh_or_undef> and C<0> for C<$events>).
		248
		249	If timeout is C<undef> or negative, then there will be no
		250	timeout. Otherwise a EV::timer with this value will be started.
		251
		252	When an error occurs or either the timeout or I/O watcher triggers, then
		253	the callback will be called with the received event set (in general
		254	you can expect it to be a combination of C<EV::ERROR>, C<EV::READ>,
		255	C<EV::WRITE> and C<EV::TIMEOUT>).
		256
		257	EV::once doesn't return anything: the watchers stay active till either
		258	of them triggers, then they will be stopped and freed, and the callback
		259	invoked.
		260
		261	=item EV::feed_fd_event ($fd, $revents)
		262
		263	=item $loop->feed_fd_event ($fd, $revents)
		264
		265	Feed an event on a file descriptor into EV. EV will react to this call as
		266	if the readyness notifications specified by C<$revents> (a combination of
		267	C<EV::READ> and C<EV::WRITE>) happened on the file descriptor C<$fd>.
		268
		269	=item EV::feed_signal_event ($signal)
		270
		271	Feed a signal event into EV. EV will react to this call as if the signal
		272	specified by C<$signal> had occured.
		273
		274	=item EV::set_io_collect_interval $time
		275
		276	=item $loop->set_io_collect_interval ($time)
		277
		278	=item EV::set_timeout_collect_interval $time
		279
		280	=item $loop->set_timeout_collect_interval ($time)
		281
		282	These advanced functions set the minimum block interval when polling for I/O events and the minimum
		283	wait interval for timer events. See the libev documentation at
		284	L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#FUNCTIONS_CONTROLLING_THE_EVENT_LOOP> for
		285	a more detailed discussion.
		286
		287	=back
		288
		289
		290	=head1 WATCHER OBJECTS
128		291
129	A watcher is an object that gets created to record your interest in some	292	A watcher is an object that gets created to record your interest in some
130	event. For instance, if you want to wait for STDIN to become readable, you	293	event. For instance, if you want to wait for STDIN to become readable, you
131	would create an EV::io watcher for that:	294	would create an EV::io watcher for that:
132		295
133	my $watcher = EV::io *STDIN, EV::READ, sub {	296	my $watcher = EV::io *STDIN, EV::READ, sub {
134	my ($watcher, $revents) = @_;	297	my ($watcher, $revents) = @_;
135	warn "yeah, STDIN should not be readable without blocking!\n"	298	warn "yeah, STDIN should now be readable without blocking!\n"
136	};	299	};
137		300
138	All watchers can be active (waiting for events) or inactive (paused). Only	301	All watchers can be active (waiting for events) or inactive (paused). Only
139	active watchers will have their callbacks invoked. All callbacks will be	302	active watchers will have their callbacks invoked. All callbacks will be
140	called with at least two arguments: the watcher and a bitmask of received	303	called with at least two arguments: the watcher and a bitmask of received
141	events.	304	events.
142		305
143	Each watcher type has its associated bit in revents, so you can use the	306	Each watcher type has its associated bit in revents, so you can use the
144	same callback for multiple watchers. The event mask is named after the	307	same callback for multiple watchers. The event mask is named after the
145	type, i..e. EV::child sets EV::CHILD, EV::prepare sets EV::PREPARE,	308	type, i..e. EV::child sets EV::CHILD, EV::prepare sets EV::PREPARE,
146	EV::periodic sets EV::PERIODIC and so on, with the exception of IO events	309	EV::periodic sets EV::PERIODIC and so on, with the exception of I/O events
147	(which can set both EV::READ and EV::WRITE bits), and EV::timer (which	310	(which can set both EV::READ and EV::WRITE bits), and EV::timer (which
148	uses EV::TIMEOUT).	311	uses EV::TIMEOUT).
149		312
150	In the rare case where one wants to create a watcher but not start it at	313	In the rare case where one wants to create a watcher but not start it at
151	the same time, each constructor has a variant with a trailing C<_ns> in	314	the same time, each constructor has a variant with a trailing C<_ns> in
152	its name, e.g. EV::io has a non-starting variant EV::io_ns and so on.	315	its name, e.g. EV::io has a non-starting variant EV::io_ns and so on.
153		316
154	Please note that a watcher will automatically be stopped when the watcher	317	Please note that a watcher will automatically be stopped when the watcher
155	object is returned, so you I<need> to keep the watcher objects returned by	318	object is destroyed, so you I<need> to keep the watcher objects returned by
156	the constructors.	319	the constructors.
157		320
158	=head2 WATCHER TYPES	321	Also, all methods changing some aspect of a watcher (->set, ->priority,
		322	->fh and so on) automatically stop and start it again if it is active,
		323	which means pending events get lost.
159		324
160	Now lets move to the existing watcher types and asociated methods.	325	=head2 COMMON WATCHER METHODS
161		326
162	The following methods are available for all watchers. Then followes a	327	This section lists methods common to all watchers.
163	description of each watcher constructor (EV::io, EV::timer, EV::periodic,
164	EV::signal, EV::child, EV::idle, EV::prepare and EV::check), followed by
165	any type-specific methods (if any).
166		328
167	=over 4	329	=over 4
168		330
169	=item $w->start	331	=item $w->start
170		332
…		…
174		336
175	=item $w->stop	337	=item $w->stop
176		338
177	Stop a watcher if it is active. Also clear any pending events (events that	339	Stop a watcher if it is active. Also clear any pending events (events that
178	have been received but that didn't yet result in a callback invocation),	340	have been received but that didn't yet result in a callback invocation),
179	regardless of wether the watcher was active or not.	341	regardless of whether the watcher was active or not.
180		342
181	=item $bool = $w->is_active	343	=item $bool = $w->is_active
182		344
183	Returns true if the watcher is active, false otherwise.	345	Returns true if the watcher is active, false otherwise.
184		346
		347	=item $current_data = $w->data
		348
		349	=item $old_data = $w->data ($new_data)
		350
		351	Queries a freely usable data scalar on the watcher and optionally changes
		352	it. This is a way to associate custom data with a watcher:
		353
		354	my $w = EV::timer 60, 0, sub {
		355	warn $_[0]->data;
		356	};
		357	$w->data ("print me!");
		358
185	=item $current_cb = $w->cb	359	=item $current_cb = $w->cb
186		360
187	=item $old_cb = $w->cb ($new_cb)	361	=item $old_cb = $w->cb ($new_cb)
188		362
189	Queries the callback on the watcher and optionally changes it. You cna do	363	Queries the callback on the watcher and optionally changes it. You can do
190	this at any time.	364	this at any time without the watcher restarting.
191		365
		366	=item $current_priority = $w->priority
		367
		368	=item $old_priority = $w->priority ($new_priority)
		369
		370	Queries the priority on the watcher and optionally changes it. Pending
		371	watchers with higher priority will be invoked first. The valid range of
		372	priorities lies between EV::MAXPRI (default 2) and EV::MINPRI (default
		373	-2). If the priority is outside this range it will automatically be
		374	normalised to the nearest valid priority.
		375
		376	The default priority of any newly-created watcher is 0.
		377
		378	Note that the priority semantics have not yet been fleshed out and are
		379	subject to almost certain change.
		380
192	=item $w->trigger ($revents)	381	=item $w->invoke ($revents)
193		382
194	Call the callback now with the given event mask.	383	Call the callback now with the given event mask.
195		384
		385	=item $w->feed_event ($revents)
		386
		387	Feed some events on this watcher into EV. EV will react to this call as if
		388	the watcher had received the given C<$revents> mask.
		389
		390	=item $revents = $w->clear_pending
		391
		392	If the watcher is pending, this function clears its pending status and
		393	returns its C<$revents> bitset (as if its callback was invoked). If the
		394	watcher isn't pending it does nothing and returns C<0>.
		395
		396	=item $previous_state = $w->keepalive ($bool)
		397
		398	Normally, C<EV::loop> will return when there are no active watchers
		399	(which is a "deadlock" because no progress can be made anymore). This is
		400	convinient because it allows you to start your watchers (and your jobs),
		401	call C<EV::loop> once and when it returns you know that all your jobs are
		402	finished (or they forgot to register some watchers for their task :).
		403
		404	Sometimes, however, this gets in your way, for example when the module
		405	that calls C<EV::loop> (usually the main program) is not the same module
		406	as a long-living watcher (for example a DNS client module written by
		407	somebody else even). Then you might want any outstanding requests to be
		408	handled, but you would not want to keep C<EV::loop> from returning just
		409	because you happen to have this long-running UDP port watcher.
		410
		411	In this case you can clear the keepalive status, which means that even
		412	though your watcher is active, it won't keep C<EV::loop> from returning.
		413
		414	The initial value for keepalive is true (enabled), and you cna change it
		415	any time.
		416
		417	Example: Register an I/O watcher for some UDP socket but do not keep the
		418	event loop from running just because of that watcher.
		419
		420	my $udp_socket = ...
		421	my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... };
		422	$udp_watcher->keepalive (0);
		423
		424	=item $loop = $w->loop
		425
		426	Return the loop that this watcher is attached to.
		427
		428	=back
		429
		430
		431	=head1 WATCHER TYPES
		432
		433	Each of the following subsections describes a single watcher type.
		434
		435	=head3 I/O WATCHERS - is this file descriptor readable or writable?
		436
		437	=over 4
196		438
197	=item $w = EV::io $fileno_or_fh, $eventmask, $callback	439	=item $w = EV::io $fileno_or_fh, $eventmask, $callback
198		440
199	=item $w = EV::io_ns $fileno_or_fh, $eventmask, $callback	441	=item $w = EV::io_ns $fileno_or_fh, $eventmask, $callback
200		442
		443	=item $w = $loop->io ($fileno_or_fh, $eventmask, $callback)
		444
		445	=item $w = $loop->io_ns ($fileno_or_fh, $eventmask, $callback)
		446
201	As long as the returned watcher object is alive, call the C<$callback>	447	As long as the returned watcher object is alive, call the C<$callback>
202	when the events specified in C<$eventmask>.	448	when at least one of events specified in C<$eventmask> occurs.
203		449
204	The $eventmask can be one or more of these constants ORed together:	450	The $eventmask can be one or more of these constants ORed together:
205		451
206	EV::READ wait until read() wouldn't block anymore	452	EV::READ wait until read() wouldn't block anymore
207	EV::WRITE wait until write() wouldn't block anymore	453	EV::WRITE wait until write() wouldn't block anymore
…		…
223		469
224	=item $old_eventmask = $w->events ($new_eventmask)	470	=item $old_eventmask = $w->events ($new_eventmask)
225		471
226	Returns the previously set event mask and optionally set a new one.	472	Returns the previously set event mask and optionally set a new one.
227		473
		474	=back
		475
		476
		477	=head3 TIMER WATCHERS - relative and optionally repeating timeouts
		478
		479	=over 4
228		480
229	=item $w = EV::timer $after, $repeat, $callback	481	=item $w = EV::timer $after, $repeat, $callback
230		482
231	=item $w = EV::timer_ns $after, $repeat, $callback	483	=item $w = EV::timer_ns $after, $repeat, $callback
232		484
233	Calls the callback after C<$after> seconds. If C<$repeat> is non-zero,	485	=item $w = $loop->timer ($after, $repeat, $callback)
234	the timer will be restarted (with the $repeat value as $after) after the	486
235	callback returns.	487	=item $w = $loop->timer_ns ($after, $repeat, $callback)
		488
		489	Calls the callback after C<$after> seconds (which may be fractional). If
		490	C<$repeat> is non-zero, the timer will be restarted (with the $repeat
		491	value as $after) after the callback returns.
236		492
237	This means that the callback would be called roughly after C<$after>	493	This means that the callback would be called roughly after C<$after>
238	seconds, and then every C<$repeat> seconds. "Roughly" because the time of	494	seconds, and then every C<$repeat> seconds. The timer does his best not
239	callback processing is not taken into account, so the timer will slowly	495	to drift, but it will not invoke the timer more often then once per event
240	drift. If that isn't acceptable, look at EV::periodic.	496	loop iteration, and might drift in other cases. If that isn't acceptable,
		497	look at EV::periodic, which can provide long-term stable timers.
241		498
242	The timer is based on a monotonic clock, that is if somebody is sitting	499	The timer is based on a monotonic clock, that is, if somebody is sitting
243	in front of the machine while the timer is running and changes the system	500	in front of the machine while the timer is running and changes the system
244	clock, the timer will nevertheless run (roughly) the same time.	501	clock, the timer will nevertheless run (roughly) the same time.
245		502
246	The C<timer_ns> variant doesn't start (activate) the newly created watcher.	503	The C<timer_ns> variant doesn't start (activate) the newly created watcher.
247		504
248	=item $w->set ($after, $repeat)	505	=item $w->set ($after, $repeat)
249		506
250	Reconfigures the watcher, see the constructor above for details. Can be at	507	Reconfigures the watcher, see the constructor above for details. Can be called at
251	any time.	508	any time.
252		509
253	=item $w->again	510	=item $w->again
254		511
255	Similar to the C<start> method, but has special semantics for repeating timers:	512	Similar to the C<start> method, but has special semantics for repeating timers:
		513
		514	If the timer is active and non-repeating, it will be stopped.
256		515
257	If the timer is active and repeating, reset the timeout to occur	516	If the timer is active and repeating, reset the timeout to occur
258	C<$repeat> seconds after now.	517	C<$repeat> seconds after now.
259		518
260	If the timer is active and non-repeating, it will be stopped.
261
262	If the timer is in active and repeating, start it.	519	If the timer is inactive and repeating, start it using the repeat value.
263		520
264	Otherwise do nothing.	521	Otherwise do nothing.
265		522
266	This behaviour is useful when you have a timeout for some IO	523	This behaviour is useful when you have a timeout for some IO
267	operation. You create a timer object with the same value for C<$after> and	524	operation. You create a timer object with the same value for C<$after> and
268	C<$repeat>, and then, in the read/write watcher, run the C<again> method	525	C<$repeat>, and then, in the read/write watcher, run the C<again> method
269	on the timeout.	526	on the timeout.
270		527
		528	=back
271		529
		530
		531	=head3 PERIODIC WATCHERS - to cron or not to cron?
		532
		533	=over 4
		534
272	=item $w = EV::periodic $at, $interval, $callback	535	=item $w = EV::periodic $at, $interval, $reschedule_cb, $callback
273		536
274	=item $w = EV::periodic_ns $at, $interval, $callback	537	=item $w = EV::periodic_ns $at, $interval, $reschedule_cb, $callback
275		538
276	Similar to EV::timer, but the time is given as an absolute point in time	539	=item $w = $loop->periodic ($at, $interval, $reschedule_cb, $callback)
277	(C<$at>), plus an optional C<$interval>.
278		540
279	If the C<$interval> is zero, then the callback will be called at the time	541	=item $w = $loop->periodic_ns ($at, $interval, $reschedule_cb, $callback)
280	C<$at> if that is in the future, or as soon as possible if it is in the
281	past. It will not automatically repeat.
282		542
283	If the C<$interval> is nonzero, then the watcher will always be scheduled	543	Similar to EV::timer, but is not based on relative timeouts but on
284	to time out at the next C<$at + N * $interval> time.	544	absolute times. Apart from creating "simple" timers that trigger "at" the
		545	specified time, it can also be used for non-drifting absolute timers and
		546	more complex, cron-like, setups that are not adversely affected by time
		547	jumps (i.e. when the system clock is changed by explicit date -s or other
		548	means such as ntpd). It is also the most complex watcher type in EV.
285		549
286	This can be used to schedule a callback to run at very regular intervals,	550	It has three distinct "modes":
287	as long as the processing time is less then the interval (otherwise	551
288	obviously events will be skipped).	552	=over 4
		553
		554	=item * absolute timer ($interval = $reschedule_cb = 0)
		555
		556	This time simply fires at the wallclock time C<$at> and doesn't repeat. It
		557	will not adjust when a time jump occurs, that is, if it is to be run
		558	at January 1st 2011 then it will run when the system time reaches or
		559	surpasses this time.
		560
		561	=item * repeating interval timer ($interval > 0, $reschedule_cb = 0)
		562
		563	In this mode the watcher will always be scheduled to time out at the
		564	next C<$at + N * $interval> time (for some integer N) and then repeat,
		565	regardless of any time jumps.
		566
		567	This can be used to create timers that do not drift with respect to system
		568	time:
		569
		570	my $hourly = EV::periodic 0, 3600, 0, sub { print "once/hour\n" };
		571
		572	That doesn't mean there will always be 3600 seconds in between triggers,
		573	but only that the the clalback will be called when the system time shows a
		574	full hour (UTC).
289		575
290	Another way to think about it (for the mathematically inclined) is that	576	Another way to think about it (for the mathematically inclined) is that
291	EV::periodic will try to run the callback at the next possible time where	577	EV::periodic will try to run the callback in this mode at the next
292	C<$time = $at (mod $interval)>, regardless of any time jumps.	578	possible time where C<$time = $at (mod $interval)>, regardless of any time
		579	jumps.
293		580
294	This periodic timer is based on "wallclock time", that is, if the clock	581	=item * manual reschedule mode ($reschedule_cb = coderef)
295	changes (C<ntp>, C<date -s> etc.), then the timer will nevertheless run at	582
296	the specified time.	583	In this mode $interval and $at are both being ignored. Instead, each
		584	time the periodic watcher gets scheduled, the reschedule callback
		585	($reschedule_cb) will be called with the watcher as first, and the current
		586	time as second argument.
		587
		588	I<This callback MUST NOT stop or destroy this or any other periodic
		589	watcher, ever, and MUST NOT call any event loop functions or methods>. If
		590	you need to stop it, return 1e30 and stop it afterwards. You may create
		591	and start a C<EV::prepare> watcher for this task.
		592
		593	It must return the next time to trigger, based on the passed time value
		594	(that is, the lowest time value larger than or equal to to the second
		595	argument). It will usually be called just before the callback will be
		596	triggered, but might be called at other times, too.
		597
		598	This can be used to create very complex timers, such as a timer that
		599	triggers on each midnight, local time (actually 24 hours after the last
		600	midnight, to keep the example simple. If you know a way to do it correctly
		601	in about the same space (without requiring elaborate modules), drop me a
		602	note :):
		603
		604	my $daily = EV::periodic 0, 0, sub {
		605	my ($w, $now) = @_;
		606
		607	use Time::Local ();
		608	my (undef, undef, undef, $d, $m, $y) = localtime $now;
		609	86400 + Time::Local::timelocal 0, 0, 0, $d, $m, $y
		610	}, sub {
		611	print "it's midnight or likely shortly after, now\n";
		612	};
		613
		614	=back
297		615
298	The C<periodic_ns> variant doesn't start (activate) the newly created watcher.	616	The C<periodic_ns> variant doesn't start (activate) the newly created watcher.
299		617
300	=item $w->set ($at, $interval)	618	=item $w->set ($at, $interval, $reschedule_cb)
301		619
302	Reconfigures the watcher, see the constructor above for details. Can be at	620	Reconfigures the watcher, see the constructor above for details. Can be called at
303	any time.	621	any time.
304		622
		623	=item $w->again
		624
		625	Simply stops and starts the watcher again.
		626
		627	=item $time = $w->at
		628
		629	Return the time that the watcher is expected to trigger next.
		630
		631	=back
		632
		633
		634	=head3 SIGNAL WATCHERS - signal me when a signal gets signalled!
		635
		636	=over 4
305		637
306	=item $w = EV::signal $signal, $callback	638	=item $w = EV::signal $signal, $callback
307		639
308	=item $w = EV::signal_ns $signal, $callback	640	=item $w = EV::signal_ns $signal, $callback
309		641
310	Call the callback when $signal is received (the signal can be specified	642	Call the callback when $signal is received (the signal can be specified by
311	by number or by name, just as with kill or %SIG).	643	number or by name, just as with C<kill> or C<%SIG>).
312		644
313	EV will grab the signal for the process (the kernel only allows one	645	EV will grab the signal for the process (the kernel only allows one
314	component to receive a signal at a time) when you start a signal watcher,	646	component to receive a signal at a time) when you start a signal watcher,
315	and removes it again when you stop it. Perl does the same when you	647	and removes it again when you stop it. Perl does the same when you
316	add/remove callbacks to %SIG, so watch out.	648	add/remove callbacks to C<%SIG>, so watch out.
317		649
318	You can have as many signal watchers per signal as you want.	650	You can have as many signal watchers per signal as you want.
319		651
320	The C<signal_ns> variant doesn't start (activate) the newly created watcher.	652	The C<signal_ns> variant doesn't start (activate) the newly created watcher.
321		653
322	=item $w->set ($signal)	654	=item $w->set ($signal)
323		655
324	Reconfigures the watcher, see the constructor above for details. Can be at	656	Reconfigures the watcher, see the constructor above for details. Can be
		657	called at any time.
		658
		659	=item $current_signum = $w->signal
		660
		661	=item $old_signum = $w->signal ($new_signal)
		662
		663	Returns the previously set signal (always as a number not name) and
		664	optionally set a new one.
		665
		666	=back
		667
		668
		669	=head3 CHILD WATCHERS - watch out for process status changes
		670
		671	=over 4
		672
		673	=item $w = EV::child $pid, $trace, $callback
		674
		675	=item $w = EV::child_ns $pid, $trace, $callback
		676
		677	=item $w = $loop->child ($pid, $trace, $callback)
		678
		679	=item $w = $loop->child_ns ($pid, $trace, $callback)
		680
		681	Call the callback when a status change for pid C<$pid> (or any pid
		682	if C<$pid> is 0) has been received (a status change happens when the
		683	process terminates or is killed, or, when trace is true, additionally when
		684	it is stopped or continued). More precisely: when the process receives
		685	a C<SIGCHLD>, EV will fetch the outstanding exit/wait status for all
		686	changed/zombie children and call the callback.
		687
		688	It is valid (and fully supported) to install a child watcher after a child
		689	has exited but before the event loop has started its next iteration (for
		690	example, first you C<fork>, then the new child process might exit, and
		691	only then do you install a child watcher in the parent for the new pid).
		692
		693	You can access both exit (or tracing) status and pid by using the
		694	C<rstatus> and C<rpid> methods on the watcher object.
		695
		696	You can have as many pid watchers per pid as you want, they will all be
		697	called.
		698
		699	The C<child_ns> variant doesn't start (activate) the newly created watcher.
		700
		701	=item $w->set ($pid, $trace)
		702
		703	Reconfigures the watcher, see the constructor above for details. Can be called at
325	any time.	704	any time.
326		705
		706	=item $current_pid = $w->pid
327		707
328	=item $w = EV::child $pid, $callback	708	Returns the previously set process id and optionally set a new one.
329		709
330	=item $w = EV::child_ns $pid, $callback	710	=item $exit_status = $w->rstatus
331		711
332	Call the callback when a status change for pid C<$pid> (or any pid	712	Return the exit/wait status (as returned by waitpid, see the waitpid entry
333	if C<$pid> is 0) has been received. More precisely: when the process	713	in perlfunc).
334	receives a SIGCHLD, EV will fetch the outstanding exit/wait status for all
335	changed/zombie children and call the callback.
336		714
337	Unlike all other callbacks, this callback will be called with an	715	=item $pid = $w->rpid
338	additional third argument which is the exit status. See the C<waitpid>
339	function for details.
340		716
341	You can have as many pid watchers per pid as you want.	717	Return the pid of the awaited child (useful when you have installed a
		718	watcher for all pids).
342		719
		720	=back
		721
		722
		723	=head3 STAT WATCHERS - did the file attributes just change?
		724
		725	=over 4
		726
		727	=item $w = EV::stat $path, $interval, $callback
		728
		729	=item $w = EV::stat_ns $path, $interval, $callback
		730
		731	=item $w = $loop->stat ($path, $interval, $callback)
		732
		733	=item $w = $loop->stat_ns ($path, $interval, $callback)
		734
		735	Call the callback when a file status change has been detected on
		736	C<$path>. The C<$path> does not need to exist, changing from "path exists"
		737	to "path does not exist" is a status change like any other.
		738
		739	The C<$interval> is a recommended polling interval for systems where
		740	OS-supported change notifications don't exist or are not supported. If
		741	you use C<0> then an unspecified default is used (which is highly
		742	recommended!), which is to be expected to be around five seconds usually.
		743
		744	This watcher type is not meant for massive numbers of stat watchers,
		745	as even with OS-supported change notifications, this can be
		746	resource-intensive.
		747
343	The C<child_ns> variant doesn't start (activate) the newly created watcher.	748	The C<stat_ns> variant doesn't start (activate) the newly created watcher.
344		749
345	=item $w->set ($pid)	750	=item ... = $w->stat
346		751
		752	This call is very similar to the perl C<stat> built-in: It stats (using
		753	C<lstat>) the path specified in the watcher and sets perls stat cache (as
		754	well as EV's idea of the current stat values) to the values found.
		755
		756	In scalar context, a boolean is return indicating success or failure of
		757	the stat. In list context, the same 13-value list as with stat is returned
		758	(except that the blksize and blocks fields are not reliable).
		759
		760	In the case of an error, errno is set to C<ENOENT> (regardless of the
		761	actual error value) and the C<nlink> value is forced to zero (if the stat
		762	was successful then nlink is guaranteed to be non-zero).
		763
		764	See also the next two entries for more info.
		765
		766	=item ... = $w->attr
		767
		768	Just like C<< $w->stat >>, but without the initial stat'ing: this returns
		769	the values most recently detected by EV. See the next entry for more info.
		770
		771	=item ... = $w->prev
		772
		773	Just like C<< $w->stat >>, but without the initial stat'ing: this returns
		774	the previous set of values, before the change.
		775
		776	That is, when the watcher callback is invoked, C<< $w->prev >> will be set
		777	to the values found I<before> a change was detected, while C<< $w->attr >>
		778	returns the values found leading to the change detection. The difference (if any)
		779	between C<prev> and C<attr> is what triggered the callback.
		780
		781	If you did something to the filesystem object and do not want to trigger
		782	yet another change, you can call C<stat> to update EV's idea of what the
		783	current attributes are.
		784
		785	=item $w->set ($path, $interval)
		786
347	Reconfigures the watcher, see the constructor above for details. Can be at	787	Reconfigures the watcher, see the constructor above for details. Can be
348	any time.	788	called at any time.
349		789
		790	=item $current_path = $w->path
		791
		792	=item $old_path = $w->path ($new_path)
		793
		794	Returns the previously set path and optionally set a new one.
		795
		796	=item $current_interval = $w->interval
		797
		798	=item $old_interval = $w->interval ($new_interval)
		799
		800	Returns the previously set interval and optionally set a new one. Can be
		801	used to query the actual interval used.
		802
		803	=back
		804
		805
		806	=head3 IDLE WATCHERS - when you've got nothing better to do...
		807
		808	=over 4
350		809
351	=item $w = EV::idle $callback	810	=item $w = EV::idle $callback
352		811
353	=item $w = EV::idle_ns $callback	812	=item $w = EV::idle_ns $callback
354		813
355	Call the callback when there are no pending io, timer/periodic, signal or	814	=item $w = $loop->idle ($callback)
356	child events, i.e. when the process is idle.	815
		816	=item $w = $loop->idle_ns ($callback)
		817
		818	Call the callback when there are no other pending watchers of the same or
		819	higher priority (excluding check, prepare and other idle watchers of the
		820	same or lower priority, of course). They are called idle watchers because
		821	when the watcher is the highest priority pending event in the process, the
		822	process is considered to be idle at that priority.
		823
		824	If you want a watcher that is only ever called when I<no> other events are
		825	outstanding you have to set the priority to C<EV::MINPRI>.
357		826
358	The process will not block as long as any idle watchers are active, and	827	The process will not block as long as any idle watchers are active, and
359	they will be called repeatedly until stopped.	828	they will be called repeatedly until stopped.
360		829
		830	For example, if you have idle watchers at priority C<0> and C<1>, and
		831	an I/O watcher at priority C<0>, then the idle watcher at priority C<1>
		832	and the I/O watcher will always run when ready. Only when the idle watcher
		833	at priority C<1> is stopped and the I/O watcher at priority C<0> is not
		834	pending with the C<0>-priority idle watcher be invoked.
		835
361	The C<idle_ns> variant doesn't start (activate) the newly created watcher.	836	The C<idle_ns> variant doesn't start (activate) the newly created watcher.
362		837
		838	=back
		839
		840
		841	=head3 PREPARE WATCHERS - customise your event loop!
		842
		843	=over 4
363		844
364	=item $w = EV::prepare $callback	845	=item $w = EV::prepare $callback
365		846
366	=item $w = EV::prepare_ns $callback	847	=item $w = EV::prepare_ns $callback
		848
		849	=item $w = $loop->prepare ($callback)
		850
		851	=item $w = $loop->prepare_ns ($callback)
367		852
368	Call the callback just before the process would block. You can still	853	Call the callback just before the process would block. You can still
369	create/modify any watchers at this point.	854	create/modify any watchers at this point.
370		855
371	See the EV::check watcher, below, for explanations and an example.	856	See the EV::check watcher, below, for explanations and an example.
372		857
373	The C<prepare_ns> variant doesn't start (activate) the newly created watcher.	858	The C<prepare_ns> variant doesn't start (activate) the newly created watcher.
374		859
		860	=back
		861
		862
		863	=head3 CHECK WATCHERS - customise your event loop even more!
		864
		865	=over 4
375		866
376	=item $w = EV::check $callback	867	=item $w = EV::check $callback
377		868
378	=item $w = EV::check_ns $callback	869	=item $w = EV::check_ns $callback
		870
		871	=item $w = $loop->check ($callback)
		872
		873	=item $w = $loop->check_ns ($callback)
379		874
380	Call the callback just after the process wakes up again (after it has	875	Call the callback just after the process wakes up again (after it has
381	gathered events), but before any other callbacks have been invoked.	876	gathered events), but before any other callbacks have been invoked.
382		877
383	This is used to integrate other event-based software into the EV	878	This is used to integrate other event-based software into the EV
…		…
391	# do nothing unless active	886	# do nothing unless active
392	$dispatcher->{_event_queue_h}	887	$dispatcher->{_event_queue_h}
393	or return;	888	or return;
394		889
395	# make the dispatcher handle any outstanding stuff	890	# make the dispatcher handle any outstanding stuff
		891	... not shown
396		892
397	# create an IO watcher for each and every socket	893	# create an I/O watcher for each and every socket
398	@snmp_watcher = (	894	@snmp_watcher = (
399	(map { EV::io $_, EV::READ, sub { } }	895	(map { EV::io $_, EV::READ, sub { } }
400	keys %{ $dispatcher->{_descriptors} }),	896	keys %{ $dispatcher->{_descriptors} }),
		897
		898	EV::timer +($event->[Net::SNMP::Dispatcher::_ACTIVE]
		899	? $event->[Net::SNMP::Dispatcher::_TIME] - EV::now : 0),
		900	0, sub { },
401	);	901	);
402
403	# if there are any timeouts, also create a timer
404	push @snmp_watcher, EV::timer $event->[Net::SNMP::Dispatcher::_TIME] - EV::now, 0, sub { }
405	if $event->[Net::SNMP::Dispatcher::_ACTIVE];
406	};	902	};
407		903
408	The callbacks are irrelevant, the only purpose of those watchers is	904	The callbacks are irrelevant (and are not even being called), the
409	to wake up the process as soon as one of those events occurs (socket	905	only purpose of those watchers is to wake up the process as soon as
410	readable, or timer timed out). The corresponding EV::check watcher will then	906	one of those events occurs (socket readable, or timer timed out). The
411	clean up:	907	corresponding EV::check watcher will then clean up:
412		908
413	our $snmp_check = EV::check sub {	909	our $snmp_check = EV::check sub {
414	# destroy all watchers	910	# destroy all watchers
415	@snmp_watcher = ();	911	@snmp_watcher = ();
416		912
417	# make the dispatcher handle any new stuff	913	# make the dispatcher handle any new stuff
		914	... not shown
418	};	915	};
419		916
420	The callbacks of the created watchers will not be called as the watchers	917	The callbacks of the created watchers will not be called as the watchers
421	are destroyed before this cna happen (remember EV::check gets called	918	are destroyed before this cna happen (remember EV::check gets called
422	first).	919	first).
423		920
424	The C<check_ns> variant doesn't start (activate) the newly created watcher.	921	The C<check_ns> variant doesn't start (activate) the newly created watcher.
425		922
426	=back	923	=back
427		924
		925
		926	=head3 FORK WATCHERS - the audacity to resume the event loop after a fork
		927
		928	Fork watchers are called when a C<fork ()> was detected. The invocation
		929	is done before the event loop blocks next and before C<check> watchers
		930	are being called, and only in the child after the fork.
		931
		932	=over 4
		933
		934	=item $w = EV::fork $callback
		935
		936	=item $w = EV::fork_ns $callback
		937
		938	=item $w = $loop->fork ($callback)
		939
		940	=item $w = $loop->fork_ns ($callback)
		941
		942	Call the callback before the event loop is resumed in the child process
		943	after a fork.
		944
		945	The C<fork_ns> variant doesn't start (activate) the newly created watcher.
		946
		947	=back
		948
		949
		950	=head3 EMBED WATCHERS - when one backend isn't enough...
		951
		952	This is a rather advanced watcher type that lets you embed one event loop
		953	into another (currently only IO events are supported in the embedded
		954	loop, other types of watchers might be handled in a delayed or incorrect
		955	fashion and must not be used).
		956
		957	See the libev documentation at
		958	L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#code_ev_embed_code_when_one_backend_>
		959	for more details.
		960
		961	In short, this watcher is most useful on BSD systems without working
		962	kqueue to still be able to handle a large number of sockets:
		963
		964	my $socket_loop;
		965
		966	# check wether we use SELECT or POLL _and_ KQUEUE is supported
		967	if (
		968	(EV::backend & (EV::BACKEND_POLL \| EV::BACKEND_SELECT))
		969	&& (EV::supported_backends & EV::embeddable_backends & EV::BACKEND_KQUEUE)
		970	) {
		971	# use kqueue for sockets
		972	$socket_loop = new EV::Loop EV::BACKEND_KQUEUE \| EV::FLAG_NOENV;
		973	}
		974
		975	# use the default loop otherwise
		976	$socket_loop \|\|= EV::default_loop;
		977
		978	=over 4
		979
		980	=item $w = EV::embed $otherloop, $callback
		981
		982	=item $w = EV::embed_ns $otherloop, $callback
		983
		984	=item $w = $loop->embed ($otherloop, $callback)
		985
		986	=item $w = $loop->embed_ns ($otherloop, $callback)
		987
		988	Call the callback when the embedded event loop (C<$otherloop>) has any
		989	I/O activity. The C<$callback> should alwas be specified as C<undef> in
		990	this version of EV, which means the embedded event loop will be managed
		991	automatically.
		992
		993	The C<embed_ns> variant doesn't start (activate) the newly created watcher.
		994
		995	=back
		996
		997	=head3 ASYNC WATCHERS - how to wake up another event loop
		998
		999	Async watchers are provided by EV, but have little use in perl directly, as perl
		1000	neither supports threads nor direct access to signal handlers or other
		1001	contexts where they could be of value.
		1002
		1003	It is, however, possible to use them from the XS level.
		1004
		1005	Please see the libev documentation for further details.
		1006
		1007	=over 4
		1008
		1009	=item $w = EV::async $callback
		1010
		1011	=item $w = EV::async_ns $callback
		1012
		1013	=item $w->send
		1014
		1015	=item $bool = $w->async_pending
		1016
		1017	=back
		1018
		1019
		1020	=head1 PERL SIGNALS
		1021
		1022	While Perl signal handling (C<%SIG>) is not affected by EV, the behaviour
		1023	with EV is as the same as any other C library: Perl-signals will only be
		1024	handled when Perl runs, which means your signal handler might be invoked
		1025	only the next time an event callback is invoked.
		1026
		1027	The solution is to use EV signal watchers (see C<EV::signal>), which will
		1028	ensure proper operations with regards to other event watchers.
		1029
		1030	If you cannot do this for whatever reason, you can also force a watcher
		1031	to be called on every event loop iteration by installing a C<EV::check>
		1032	watcher:
		1033
		1034	my $async_check = EV::check sub { };
		1035
		1036	This ensures that perl gets into control for a short time to handle any
		1037	pending signals, and also ensures (slightly) slower overall operation.
		1038
428	=head1 THREADS	1039	=head1 THREADS
429		1040
430	Threads are not supported by this in any way. Perl pseudo-threads is evil	1041	Threads are not supported by this module in any way. Perl pseudo-threads
431	stuff and must die.	1042	is evil stuff and must die. As soon as Perl gains real threads I will work
		1043	on thread support for it.
		1044
		1045	=head1 FORK
		1046
		1047	Most of the "improved" event delivering mechanisms of modern operating
		1048	systems have quite a few problems with fork(2) (to put it bluntly: it is
		1049	not supported and usually destructive). Libev makes it possible to work
		1050	around this by having a function that recreates the kernel state after
		1051	fork in the child.
		1052
		1053	On non-win32 platforms, this module requires the pthread_atfork
		1054	functionality to do this automatically for you. This function is quite
		1055	buggy on most BSDs, though, so YMMV. The overhead for this is quite
		1056	negligible, because everything the function currently does is set a flag
		1057	that is checked only when the event loop gets used the next time, so when
		1058	you do fork but not use EV, the overhead is minimal.
		1059
		1060	On win32, there is no notion of fork so all this doesn't apply, of course.
432		1061
433	=cut	1062	=cut
434		1063
435	our $DIED = sub {	1064	our $DIED = sub {
436	warn "EV: error in callback (ignoring): $@";	1065	warn "EV: error in callback (ignoring): $@";
437	};	1066	};
438		1067
439	init;	1068	default_loop
440		1069	or die 'EV: cannot initialise libev backend. bad $ENV{LIBEV_FLAGS}?';
441	push @AnyEvent::REGISTRY, [EV => "EV::AnyEvent"];
442		1070
443	1;	1071	1;
444		1072
445	=head1 SEE ALSO	1073	=head1 SEE ALSO
446		1074
447	L<EV::DNS>, L<EV::AnyEvent>.	1075	L<EV::ADNS> (asynchronous DNS), L<Glib::EV> (makes Glib/Gtk2 use EV as
		1076	event loop), L<EV::Glib> (embed Glib into EV), L<Coro::EV> (efficient
		1077	coroutines with EV), L<Net::SNMP::EV> (asynchronous SNMP), L<AnyEvent> for
		1078	event-loop agnostic and portable event driven programming.
448		1079
449	=head1 AUTHOR	1080	=head1 AUTHOR
450		1081
451	Marc Lehmann <schmorp@schmorp.de>	1082	Marc Lehmann <schmorp@schmorp.de>
452	http://home.schmorp.de/	1083	http://home.schmorp.de/
453		1084
454	=cut	1085	=cut
455		1086

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Comparing EV/EV.pm (file contents): Revision 1.20 by root, Thu Nov 1 17:17:32 2007 UTC vs. Revision 1.99 by root, Tue Jul 8 09:37:37 2008 UTC

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Comparing EV/EV.pm (file contents):
Revision 1.20 by root, Thu Nov 1 17:17:32 2007 UTC vs.
Revision 1.99 by root, Tue Jul 8 09:37:37 2008 UTC