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

Comparing EV/EV.pm (file contents):
Revision 1.21 by root, Thu Nov 1 17:20:25 2007 UTC vs.
Revision 1.101 by root, Sat Jul 12 22:19:22 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
		76	no warnings;
62	use strict;	77	use strict;
63		78
64	BEGIN {	79	BEGIN {
65	our $VERSION = '0.1';	80	our $VERSION = '3.431';
66	use XSLoader;	81	use XSLoader;
67	XSLoader::load "EV", $VERSION;	82	XSLoader::load "EV", $VERSION;
68	}	83	}
69		84
70	@EV::Io::ISA =	85	@EV::IO::ISA =
71	@EV::Timer::ISA =	86	@EV::Timer::ISA =
72	@EV::Periodic::ISA =	87	@EV::Periodic::ISA =
73	@EV::Signal::ISA =	88	@EV::Signal::ISA =
		89	@EV::Child::ISA =
		90	@EV::Stat::ISA =
74	@EV::Idle::ISA =	91	@EV::Idle::ISA =
75	@EV::Prepare::ISA =	92	@EV::Prepare::ISA =
76	@EV::Check::ISA =	93	@EV::Check::ISA =
77	@EV::Child::ISA = "EV::Watcher";	94	@EV::Embed::ISA =
		95	@EV::Fork::ISA =
		96	@EV::Async::ISA =
		97	"EV::Watcher";
		98
		99	@EV::Loop::Default::ISA = "EV::Loop";
		100
		101	=head1 EVENT LOOPS
		102
		103	EV supports multiple event loops: There is a single "default event loop"
		104	that can handle everything including signals and child watchers, and any
		105	number of "dynamic event loops" that can use different backends (with
		106	various limitations), but no child and signal watchers.
		107
		108	You do not have to do anything to create the default event loop: When
		109	the module is loaded a suitable backend is selected on the premise of
		110	selecting a working backend (which for example rules out kqueue on most
		111	BSDs). Modules should, unless they have "special needs" always use the
		112	default loop as this is fastest (perl-wise), best supported by other
		113	modules (e.g. AnyEvent or Coro) and most portable event loop.
		114
		115	For specific programs you can create additional event loops dynamically.
		116
		117	If you want to take avdantage of kqueue (which often works properly for
		118	sockets only) even though the default loop doesn't enable it, you can
		119	I<embed> a kqueue loop into the default loop: running the default loop
		120	will then also service the kqueue loop to some extent. See the example in
		121	the section about embed watchers for an example on how to achieve that.
		122
		123	=over 4
		124
		125	=item $loop = new EV::loop [$flags]
		126
		127	Create a new event loop as per the specified flags. Please refer to the
		128	C<ev_loop_new ()> function description in the libev documentation
		129	(L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#GLOBAL_FUNCTIONS>)
		130	for more info.
		131
		132	The loop will automatically be destroyed when it is no longer referenced
		133	by any watcher and the loop object goes out of scope.
		134
		135	Using C<EV::FLAG_FORKCHECK> is recommended, as only the default event loop
		136	is protected by this module.
		137
		138	=item $loop->loop_fork
		139
		140	Must be called after a fork in the child, before entering or continuing
		141	the event loop. An alternative is to use C<EV::FLAG_FORKCHECK> which calls
		142	this function automatically, at some performance loss (refer to the libev
		143	documentation).
		144
		145	=item $loop->loop_verify
		146
		147	Calls C<ev_verify> to make internal consistency checks (for debugging
		148	libev) and abort the program if any data structures were found to be
		149	corrupted.
		150
		151	=item $loop = EV::default_loop [$flags]
		152
		153	Return the default loop (which is a singleton object). Since this module
		154	already creates the default loop with default flags, specifying flags here
		155	will not have any effect unless you destroy the default loop first, which
		156	isn't supported. So in short: don't do it, and if you break it, you get to
		157	keep the pieces.
		158
		159	=back
		160
78		161
79	=head1 BASIC INTERFACE	162	=head1 BASIC INTERFACE
80		163
81	=over 4	164	=over 4
82		165
83	=item $EV::DIED	166	=item $EV::DIED
84		167
85	Must contain a reference to a function that is called when a callback	168	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	169	throws an exception (with $@ containing the error). The default prints an
87	informative message and continues.	170	informative message and continues.
88		171
89	If this callback throws an exception it will be silently ignored.	172	If this callback throws an exception it will be silently ignored.
90		173
		174	=item $flags = EV::supported_backends
		175
		176	=item $flags = EV::recommended_backends
		177
		178	=item $flags = EV::embeddable_backends
		179
		180	Returns the set (see C<EV::BACKEND_*> flags) of backends supported by this
		181	instance of EV, the set of recommended backends (supposed to be good) for
		182	this platform and the set of embeddable backends (see EMBED WATCHERS).
		183
		184	=item EV::sleep $seconds
		185
		186	Block the process for the given number of (fractional) seconds.
		187
91	=item $time = EV::time	188	=item $time = EV::time
92		189
93	Returns the current time in (fractional) seconds since the epoch.	190	Returns the current time in (fractional) seconds since the epoch.
94		191
95	=item $time = EV::now	192	=item $time = EV::now
		193
		194	=item $time = $loop->now
96		195
97	Returns the time the last event loop iteration has been started. This	196	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	197	is the time that (relative) timers are based on, and refering to it is
99	usually faster then calling EV::time.	198	usually faster then calling EV::time.
100		199
101	=item $method = EV::ev_method	200	=item $backend = EV::backend
		201
		202	=item $backend = $loop->backend
102		203
103	Returns an integer describing the backend used by libev (EV::METHOD_SELECT	204	Returns an integer describing the backend used by libev (EV::METHOD_SELECT
104	or EV::METHOD_EPOLL).	205	or EV::METHOD_EPOLL).
105		206
106	=item EV::loop [$flags]	207	=item EV::loop [$flags]
107		208
		209	=item $loop->loop ([$flags])
		210
108	Begin checking for events and calling callbacks. It returns when a	211	Begin checking for events and calling callbacks. It returns when a
109	callback calls EV::loop_done.	212	callback calls EV::unloop.
110		213
111	The $flags argument can be one of the following:	214	The $flags argument can be one of the following:
112		215
113	0 as above	216	0 as above
114	EV::LOOP_ONESHOT block at most once (wait, but do not loop)	217	EV::LOOP_ONESHOT block at most once (wait, but do not loop)
115	EV::LOOP_NONBLOCK do not block at all (fetch/handle events but do not wait)	218	EV::LOOP_NONBLOCK do not block at all (fetch/handle events but do not wait)
116		219
117	=item EV::loop_done [$how]	220	=item EV::unloop [$how]
118		221
		222	=item $loop->unloop ([$how])
		223
119	When called with no arguments or an argument of 1, makes the innermost	224	When called with no arguments or an argument of EV::UNLOOP_ONE, makes the
120	call to EV::loop return.	225	innermost call to EV::loop return.
121		226
122	When called with an agrument of 2, all calls to EV::loop will return as	227	When called with an argument of EV::UNLOOP_ALL, all calls to EV::loop will return as
123	fast as possible.	228	fast as possible.
124		229
125	=back	230	=item $count = EV::loop_count
126		231
127	=head2 WATCHER	232	=item $count = $loop->loop_count
		233
		234	Return the number of times the event loop has polled for new
		235	events. Sometiems useful as a generation counter.
		236
		237	=item EV::once $fh_or_undef, $events, $timeout, $cb->($revents)
		238
		239	=item $loop->once ($fh_or_undef, $events, $timeout, $cb->($revents))
		240
		241	This function rolls together an I/O and a timer watcher for a single
		242	one-shot event without the need for managing a watcher object.
		243
		244	If C<$fh_or_undef> is a filehandle or file descriptor, then C<$events>
		245	must be a bitset containing either C<EV::READ>, C<EV::WRITE> or C<EV::READ
		246	\| EV::WRITE>, indicating the type of I/O event you want to wait for. If
		247	you do not want to wait for some I/O event, specify C<undef> for
		248	C<$fh_or_undef> and C<0> for C<$events>).
		249
		250	If timeout is C<undef> or negative, then there will be no
		251	timeout. Otherwise a EV::timer with this value will be started.
		252
		253	When an error occurs or either the timeout or I/O watcher triggers, then
		254	the callback will be called with the received event set (in general
		255	you can expect it to be a combination of C<EV::ERROR>, C<EV::READ>,
		256	C<EV::WRITE> and C<EV::TIMEOUT>).
		257
		258	EV::once doesn't return anything: the watchers stay active till either
		259	of them triggers, then they will be stopped and freed, and the callback
		260	invoked.
		261
		262	=item EV::feed_fd_event ($fd, $revents)
		263
		264	=item $loop->feed_fd_event ($fd, $revents)
		265
		266	Feed an event on a file descriptor into EV. EV will react to this call as
		267	if the readyness notifications specified by C<$revents> (a combination of
		268	C<EV::READ> and C<EV::WRITE>) happened on the file descriptor C<$fd>.
		269
		270	=item EV::feed_signal_event ($signal)
		271
		272	Feed a signal event into EV. EV will react to this call as if the signal
		273	specified by C<$signal> had occured.
		274
		275	=item EV::set_io_collect_interval $time
		276
		277	=item $loop->set_io_collect_interval ($time)
		278
		279	=item EV::set_timeout_collect_interval $time
		280
		281	=item $loop->set_timeout_collect_interval ($time)
		282
		283	These advanced functions set the minimum block interval when polling for I/O events and the minimum
		284	wait interval for timer events. See the libev documentation at
		285	L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#FUNCTIONS_CONTROLLING_THE_EVENT_LOOP> for
		286	a more detailed discussion.
		287
		288	=back
		289
		290
		291	=head1 WATCHER OBJECTS
128		292
129	A watcher is an object that gets created to record your interest in some	293	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	294	event. For instance, if you want to wait for STDIN to become readable, you
131	would create an EV::io watcher for that:	295	would create an EV::io watcher for that:
132		296
133	my $watcher = EV::io *STDIN, EV::READ, sub {	297	my $watcher = EV::io *STDIN, EV::READ, sub {
134	my ($watcher, $revents) = @_;	298	my ($watcher, $revents) = @_;
135	warn "yeah, STDIN should not be readable without blocking!\n"	299	warn "yeah, STDIN should now be readable without blocking!\n"
136	};	300	};
137		301
138	All watchers can be active (waiting for events) or inactive (paused). Only	302	All watchers can be active (waiting for events) or inactive (paused). Only
139	active watchers will have their callbacks invoked. All callbacks will be	303	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	304	called with at least two arguments: the watcher and a bitmask of received
141	events.	305	events.
142		306
143	Each watcher type has its associated bit in revents, so you can use the	307	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	308	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,	309	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	310	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	311	(which can set both EV::READ and EV::WRITE bits), and EV::timer (which
148	uses EV::TIMEOUT).	312	uses EV::TIMEOUT).
149		313
150	In the rare case where one wants to create a watcher but not start it at	314	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	315	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.	316	its name, e.g. EV::io has a non-starting variant EV::io_ns and so on.
153		317
154	Please note that a watcher will automatically be stopped when the watcher	318	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	319	object is destroyed, so you I<need> to keep the watcher objects returned by
156	the constructors.	320	the constructors.
157		321
158	=head2 WATCHER TYPES	322	Also, all methods changing some aspect of a watcher (->set, ->priority,
		323	->fh and so on) automatically stop and start it again if it is active,
		324	which means pending events get lost.
159		325
160	Now lets move to the existing watcher types and asociated methods.	326	=head2 COMMON WATCHER METHODS
161		327
162	The following methods are available for all watchers. Then followes a	328	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		329
167	=over 4	330	=over 4
168		331
169	=item $w->start	332	=item $w->start
170		333
…		…
174		337
175	=item $w->stop	338	=item $w->stop
176		339
177	Stop a watcher if it is active. Also clear any pending events (events that	340	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),	341	have been received but that didn't yet result in a callback invocation),
179	regardless of wether the watcher was active or not.	342	regardless of whether the watcher was active or not.
180		343
181	=item $bool = $w->is_active	344	=item $bool = $w->is_active
182		345
183	Returns true if the watcher is active, false otherwise.	346	Returns true if the watcher is active, false otherwise.
184		347
		348	=item $current_data = $w->data
		349
		350	=item $old_data = $w->data ($new_data)
		351
		352	Queries a freely usable data scalar on the watcher and optionally changes
		353	it. This is a way to associate custom data with a watcher:
		354
		355	my $w = EV::timer 60, 0, sub {
		356	warn $_[0]->data;
		357	};
		358	$w->data ("print me!");
		359
185	=item $current_cb = $w->cb	360	=item $current_cb = $w->cb
186		361
187	=item $old_cb = $w->cb ($new_cb)	362	=item $old_cb = $w->cb ($new_cb)
188		363
189	Queries the callback on the watcher and optionally changes it. You cna do	364	Queries the callback on the watcher and optionally changes it. You can do
190	this at any time.	365	this at any time without the watcher restarting.
191		366
		367	=item $current_priority = $w->priority
		368
		369	=item $old_priority = $w->priority ($new_priority)
		370
		371	Queries the priority on the watcher and optionally changes it. Pending
		372	watchers with higher priority will be invoked first. The valid range of
		373	priorities lies between EV::MAXPRI (default 2) and EV::MINPRI (default
		374	-2). If the priority is outside this range it will automatically be
		375	normalised to the nearest valid priority.
		376
		377	The default priority of any newly-created watcher is 0.
		378
		379	Note that the priority semantics have not yet been fleshed out and are
		380	subject to almost certain change.
		381
192	=item $w->trigger ($revents)	382	=item $w->invoke ($revents)
193		383
194	Call the callback now with the given event mask.	384	Call the callback now with the given event mask.
195		385
		386	=item $w->feed_event ($revents)
		387
		388	Feed some events on this watcher into EV. EV will react to this call as if
		389	the watcher had received the given C<$revents> mask.
		390
		391	=item $revents = $w->clear_pending
		392
		393	If the watcher is pending, this function clears its pending status and
		394	returns its C<$revents> bitset (as if its callback was invoked). If the
		395	watcher isn't pending it does nothing and returns C<0>.
		396
		397	=item $previous_state = $w->keepalive ($bool)
		398
		399	Normally, C<EV::loop> will return when there are no active watchers
		400	(which is a "deadlock" because no progress can be made anymore). This is
		401	convinient because it allows you to start your watchers (and your jobs),
		402	call C<EV::loop> once and when it returns you know that all your jobs are
		403	finished (or they forgot to register some watchers for their task :).
		404
		405	Sometimes, however, this gets in your way, for example when the module
		406	that calls C<EV::loop> (usually the main program) is not the same module
		407	as a long-living watcher (for example a DNS client module written by
		408	somebody else even). Then you might want any outstanding requests to be
		409	handled, but you would not want to keep C<EV::loop> from returning just
		410	because you happen to have this long-running UDP port watcher.
		411
		412	In this case you can clear the keepalive status, which means that even
		413	though your watcher is active, it won't keep C<EV::loop> from returning.
		414
		415	The initial value for keepalive is true (enabled), and you cna change it
		416	any time.
		417
		418	Example: Register an I/O watcher for some UDP socket but do not keep the
		419	event loop from running just because of that watcher.
		420
		421	my $udp_socket = ...
		422	my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... };
		423	$udp_watcher->keepalive (0);
		424
		425	=item $loop = $w->loop
		426
		427	Return the loop that this watcher is attached to.
		428
		429	=back
		430
		431
		432	=head1 WATCHER TYPES
		433
		434	Each of the following subsections describes a single watcher type.
		435
		436	=head3 I/O WATCHERS - is this file descriptor readable or writable?
		437
		438	=over 4
196		439
197	=item $w = EV::io $fileno_or_fh, $eventmask, $callback	440	=item $w = EV::io $fileno_or_fh, $eventmask, $callback
198		441
199	=item $w = EV::io_ns $fileno_or_fh, $eventmask, $callback	442	=item $w = EV::io_ns $fileno_or_fh, $eventmask, $callback
200		443
		444	=item $w = $loop->io ($fileno_or_fh, $eventmask, $callback)
		445
		446	=item $w = $loop->io_ns ($fileno_or_fh, $eventmask, $callback)
		447
201	As long as the returned watcher object is alive, call the C<$callback>	448	As long as the returned watcher object is alive, call the C<$callback>
202	when the events specified in C<$eventmask>.	449	when at least one of events specified in C<$eventmask> occurs.
203		450
204	The $eventmask can be one or more of these constants ORed together:	451	The $eventmask can be one or more of these constants ORed together:
205		452
206	EV::READ wait until read() wouldn't block anymore	453	EV::READ wait until read() wouldn't block anymore
207	EV::WRITE wait until write() wouldn't block anymore	454	EV::WRITE wait until write() wouldn't block anymore
…		…
223		470
224	=item $old_eventmask = $w->events ($new_eventmask)	471	=item $old_eventmask = $w->events ($new_eventmask)
225		472
226	Returns the previously set event mask and optionally set a new one.	473	Returns the previously set event mask and optionally set a new one.
227		474
		475	=back
		476
		477
		478	=head3 TIMER WATCHERS - relative and optionally repeating timeouts
		479
		480	=over 4
228		481
229	=item $w = EV::timer $after, $repeat, $callback	482	=item $w = EV::timer $after, $repeat, $callback
230		483
231	=item $w = EV::timer_ns $after, $repeat, $callback	484	=item $w = EV::timer_ns $after, $repeat, $callback
232		485
233	Calls the callback after C<$after> seconds. If C<$repeat> is non-zero,	486	=item $w = $loop->timer ($after, $repeat, $callback)
234	the timer will be restarted (with the $repeat value as $after) after the	487
235	callback returns.	488	=item $w = $loop->timer_ns ($after, $repeat, $callback)
		489
		490	Calls the callback after C<$after> seconds (which may be fractional). If
		491	C<$repeat> is non-zero, the timer will be restarted (with the $repeat
		492	value as $after) after the callback returns.
236		493
237	This means that the callback would be called roughly after C<$after>	494	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	495	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	496	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.	497	loop iteration, and might drift in other cases. If that isn't acceptable,
		498	look at EV::periodic, which can provide long-term stable timers.
241		499
242	The timer is based on a monotonic clock, that is if somebody is sitting	500	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	501	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.	502	clock, the timer will nevertheless run (roughly) the same time.
245		503
246	The C<timer_ns> variant doesn't start (activate) the newly created watcher.	504	The C<timer_ns> variant doesn't start (activate) the newly created watcher.
247		505
248	=item $w->set ($after, $repeat)	506	=item $w->set ($after, $repeat)
249		507
250	Reconfigures the watcher, see the constructor above for details. Can be at	508	Reconfigures the watcher, see the constructor above for details. Can be called at
251	any time.	509	any time.
252		510
253	=item $w->again	511	=item $w->again
254		512
255	Similar to the C<start> method, but has special semantics for repeating timers:	513	Similar to the C<start> method, but has special semantics for repeating timers:
		514
		515	If the timer is active and non-repeating, it will be stopped.
256		516
257	If the timer is active and repeating, reset the timeout to occur	517	If the timer is active and repeating, reset the timeout to occur
258	C<$repeat> seconds after now.	518	C<$repeat> seconds after now.
259		519
260	If the timer is active and non-repeating, it will be stopped.
261
262	If the timer is in active and repeating, start it.	520	If the timer is inactive and repeating, start it using the repeat value.
263		521
264	Otherwise do nothing.	522	Otherwise do nothing.
265		523
266	This behaviour is useful when you have a timeout for some IO	524	This behaviour is useful when you have a timeout for some IO
267	operation. You create a timer object with the same value for C<$after> and	525	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	526	C<$repeat>, and then, in the read/write watcher, run the C<again> method
269	on the timeout.	527	on the timeout.
270		528
		529	=back
271		530
		531
		532	=head3 PERIODIC WATCHERS - to cron or not to cron?
		533
		534	=over 4
		535
272	=item $w = EV::periodic $at, $interval, $callback	536	=item $w = EV::periodic $at, $interval, $reschedule_cb, $callback
273		537
274	=item $w = EV::periodic_ns $at, $interval, $callback	538	=item $w = EV::periodic_ns $at, $interval, $reschedule_cb, $callback
275		539
276	Similar to EV::timer, but the time is given as an absolute point in time	540	=item $w = $loop->periodic ($at, $interval, $reschedule_cb, $callback)
277	(C<$at>), plus an optional C<$interval>.
278		541
279	If the C<$interval> is zero, then the callback will be called at the time	542	=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		543
283	If the C<$interval> is nonzero, then the watcher will always be scheduled	544	Similar to EV::timer, but is not based on relative timeouts but on
284	to time out at the next C<$at + N * $interval> time.	545	absolute times. Apart from creating "simple" timers that trigger "at" the
		546	specified time, it can also be used for non-drifting absolute timers and
		547	more complex, cron-like, setups that are not adversely affected by time
		548	jumps (i.e. when the system clock is changed by explicit date -s or other
		549	means such as ntpd). It is also the most complex watcher type in EV.
285		550
286	This can be used to schedule a callback to run at very regular intervals,	551	It has three distinct "modes":
287	as long as the processing time is less then the interval (otherwise	552
288	obviously events will be skipped).	553	=over 4
		554
		555	=item * absolute timer ($interval = $reschedule_cb = 0)
		556
		557	This time simply fires at the wallclock time C<$at> and doesn't repeat. It
		558	will not adjust when a time jump occurs, that is, if it is to be run
		559	at January 1st 2011 then it will run when the system time reaches or
		560	surpasses this time.
		561
		562	=item * repeating interval timer ($interval > 0, $reschedule_cb = 0)
		563
		564	In this mode the watcher will always be scheduled to time out at the
		565	next C<$at + N * $interval> time (for some integer N) and then repeat,
		566	regardless of any time jumps.
		567
		568	This can be used to create timers that do not drift with respect to system
		569	time:
		570
		571	my $hourly = EV::periodic 0, 3600, 0, sub { print "once/hour\n" };
		572
		573	That doesn't mean there will always be 3600 seconds in between triggers,
		574	but only that the the clalback will be called when the system time shows a
		575	full hour (UTC).
289		576
290	Another way to think about it (for the mathematically inclined) is that	577	Another way to think about it (for the mathematically inclined) is that
291	EV::periodic will try to run the callback at the next possible time where	578	EV::periodic will try to run the callback in this mode at the next
292	C<$time = $at (mod $interval)>, regardless of any time jumps.	579	possible time where C<$time = $at (mod $interval)>, regardless of any time
		580	jumps.
293		581
294	This periodic timer is based on "wallclock time", that is, if the clock	582	=item * manual reschedule mode ($reschedule_cb = coderef)
295	changes (C<ntp>, C<date -s> etc.), then the timer will nevertheless run at	583
296	the specified time. This means it will never drift (it might jitter, but	584	In this mode $interval and $at are both being ignored. Instead, each
297	it will not drift).	585	time the periodic watcher gets scheduled, the reschedule callback
		586	($reschedule_cb) will be called with the watcher as first, and the current
		587	time as second argument.
		588
		589	I<This callback MUST NOT stop or destroy this or any other periodic
		590	watcher, ever, and MUST NOT call any event loop functions or methods>. If
		591	you need to stop it, return 1e30 and stop it afterwards. You may create
		592	and start a C<EV::prepare> watcher for this task.
		593
		594	It must return the next time to trigger, based on the passed time value
		595	(that is, the lowest time value larger than or equal to to the second
		596	argument). It will usually be called just before the callback will be
		597	triggered, but might be called at other times, too.
		598
		599	This can be used to create very complex timers, such as a timer that
		600	triggers on each midnight, local time (actually 24 hours after the last
		601	midnight, to keep the example simple. If you know a way to do it correctly
		602	in about the same space (without requiring elaborate modules), drop me a
		603	note :):
		604
		605	my $daily = EV::periodic 0, 0, sub {
		606	my ($w, $now) = @_;
		607
		608	use Time::Local ();
		609	my (undef, undef, undef, $d, $m, $y) = localtime $now;
		610	86400 + Time::Local::timelocal 0, 0, 0, $d, $m, $y
		611	}, sub {
		612	print "it's midnight or likely shortly after, now\n";
		613	};
		614
		615	=back
298		616
299	The C<periodic_ns> variant doesn't start (activate) the newly created watcher.	617	The C<periodic_ns> variant doesn't start (activate) the newly created watcher.
300		618
301	=item $w->set ($at, $interval)	619	=item $w->set ($at, $interval, $reschedule_cb)
302		620
303	Reconfigures the watcher, see the constructor above for details. Can be at	621	Reconfigures the watcher, see the constructor above for details. Can be called at
304	any time.	622	any time.
305		623
		624	=item $w->again
		625
		626	Simply stops and starts the watcher again.
		627
		628	=item $time = $w->at
		629
		630	Return the time that the watcher is expected to trigger next.
		631
		632	=back
		633
		634
		635	=head3 SIGNAL WATCHERS - signal me when a signal gets signalled!
		636
		637	=over 4
306		638
307	=item $w = EV::signal $signal, $callback	639	=item $w = EV::signal $signal, $callback
308		640
309	=item $w = EV::signal_ns $signal, $callback	641	=item $w = EV::signal_ns $signal, $callback
310		642
311	Call the callback when $signal is received (the signal can be specified	643	Call the callback when $signal is received (the signal can be specified by
312	by number or by name, just as with kill or %SIG).	644	number or by name, just as with C<kill> or C<%SIG>).
313		645
314	EV will grab the signal for the process (the kernel only allows one	646	EV will grab the signal for the process (the kernel only allows one
315	component to receive a signal at a time) when you start a signal watcher,	647	component to receive a signal at a time) when you start a signal watcher,
316	and removes it again when you stop it. Perl does the same when you	648	and removes it again when you stop it. Perl does the same when you
317	add/remove callbacks to %SIG, so watch out.	649	add/remove callbacks to C<%SIG>, so watch out.
318		650
319	You can have as many signal watchers per signal as you want.	651	You can have as many signal watchers per signal as you want.
320		652
321	The C<signal_ns> variant doesn't start (activate) the newly created watcher.	653	The C<signal_ns> variant doesn't start (activate) the newly created watcher.
322		654
323	=item $w->set ($signal)	655	=item $w->set ($signal)
324		656
325	Reconfigures the watcher, see the constructor above for details. Can be at	657	Reconfigures the watcher, see the constructor above for details. Can be
		658	called at any time.
		659
		660	=item $current_signum = $w->signal
		661
		662	=item $old_signum = $w->signal ($new_signal)
		663
		664	Returns the previously set signal (always as a number not name) and
		665	optionally set a new one.
		666
		667	=back
		668
		669
		670	=head3 CHILD WATCHERS - watch out for process status changes
		671
		672	=over 4
		673
		674	=item $w = EV::child $pid, $trace, $callback
		675
		676	=item $w = EV::child_ns $pid, $trace, $callback
		677
		678	=item $w = $loop->child ($pid, $trace, $callback)
		679
		680	=item $w = $loop->child_ns ($pid, $trace, $callback)
		681
		682	Call the callback when a status change for pid C<$pid> (or any pid
		683	if C<$pid> is 0) has been received (a status change happens when the
		684	process terminates or is killed, or, when trace is true, additionally when
		685	it is stopped or continued). More precisely: when the process receives
		686	a C<SIGCHLD>, EV will fetch the outstanding exit/wait status for all
		687	changed/zombie children and call the callback.
		688
		689	It is valid (and fully supported) to install a child watcher after a child
		690	has exited but before the event loop has started its next iteration (for
		691	example, first you C<fork>, then the new child process might exit, and
		692	only then do you install a child watcher in the parent for the new pid).
		693
		694	You can access both exit (or tracing) status and pid by using the
		695	C<rstatus> and C<rpid> methods on the watcher object.
		696
		697	You can have as many pid watchers per pid as you want, they will all be
		698	called.
		699
		700	The C<child_ns> variant doesn't start (activate) the newly created watcher.
		701
		702	=item $w->set ($pid, $trace)
		703
		704	Reconfigures the watcher, see the constructor above for details. Can be called at
326	any time.	705	any time.
327		706
		707	=item $current_pid = $w->pid
328		708
329	=item $w = EV::child $pid, $callback	709	Returns the previously set process id and optionally set a new one.
330		710
331	=item $w = EV::child_ns $pid, $callback	711	=item $exit_status = $w->rstatus
332		712
333	Call the callback when a status change for pid C<$pid> (or any pid	713	Return the exit/wait status (as returned by waitpid, see the waitpid entry
334	if C<$pid> is 0) has been received. More precisely: when the process	714	in perlfunc).
335	receives a SIGCHLD, EV will fetch the outstanding exit/wait status for all
336	changed/zombie children and call the callback.
337		715
338	Unlike all other callbacks, this callback will be called with an	716	=item $pid = $w->rpid
339	additional third argument which is the exit status. See the C<waitpid>
340	function for details.
341		717
342	You can have as many pid watchers per pid as you want.	718	Return the pid of the awaited child (useful when you have installed a
		719	watcher for all pids).
343		720
		721	=back
		722
		723
		724	=head3 STAT WATCHERS - did the file attributes just change?
		725
		726	=over 4
		727
		728	=item $w = EV::stat $path, $interval, $callback
		729
		730	=item $w = EV::stat_ns $path, $interval, $callback
		731
		732	=item $w = $loop->stat ($path, $interval, $callback)
		733
		734	=item $w = $loop->stat_ns ($path, $interval, $callback)
		735
		736	Call the callback when a file status change has been detected on
		737	C<$path>. The C<$path> does not need to exist, changing from "path exists"
		738	to "path does not exist" is a status change like any other.
		739
		740	The C<$interval> is a recommended polling interval for systems where
		741	OS-supported change notifications don't exist or are not supported. If
		742	you use C<0> then an unspecified default is used (which is highly
		743	recommended!), which is to be expected to be around five seconds usually.
		744
		745	This watcher type is not meant for massive numbers of stat watchers,
		746	as even with OS-supported change notifications, this can be
		747	resource-intensive.
		748
344	The C<child_ns> variant doesn't start (activate) the newly created watcher.	749	The C<stat_ns> variant doesn't start (activate) the newly created watcher.
345		750
346	=item $w->set ($pid)	751	=item ... = $w->stat
347		752
		753	This call is very similar to the perl C<stat> built-in: It stats (using
		754	C<lstat>) the path specified in the watcher and sets perls stat cache (as
		755	well as EV's idea of the current stat values) to the values found.
		756
		757	In scalar context, a boolean is return indicating success or failure of
		758	the stat. In list context, the same 13-value list as with stat is returned
		759	(except that the blksize and blocks fields are not reliable).
		760
		761	In the case of an error, errno is set to C<ENOENT> (regardless of the
		762	actual error value) and the C<nlink> value is forced to zero (if the stat
		763	was successful then nlink is guaranteed to be non-zero).
		764
		765	See also the next two entries for more info.
		766
		767	=item ... = $w->attr
		768
		769	Just like C<< $w->stat >>, but without the initial stat'ing: this returns
		770	the values most recently detected by EV. See the next entry for more info.
		771
		772	=item ... = $w->prev
		773
		774	Just like C<< $w->stat >>, but without the initial stat'ing: this returns
		775	the previous set of values, before the change.
		776
		777	That is, when the watcher callback is invoked, C<< $w->prev >> will be set
		778	to the values found I<before> a change was detected, while C<< $w->attr >>
		779	returns the values found leading to the change detection. The difference (if any)
		780	between C<prev> and C<attr> is what triggered the callback.
		781
		782	If you did something to the filesystem object and do not want to trigger
		783	yet another change, you can call C<stat> to update EV's idea of what the
		784	current attributes are.
		785
		786	=item $w->set ($path, $interval)
		787
348	Reconfigures the watcher, see the constructor above for details. Can be at	788	Reconfigures the watcher, see the constructor above for details. Can be
349	any time.	789	called at any time.
350		790
		791	=item $current_path = $w->path
		792
		793	=item $old_path = $w->path ($new_path)
		794
		795	Returns the previously set path and optionally set a new one.
		796
		797	=item $current_interval = $w->interval
		798
		799	=item $old_interval = $w->interval ($new_interval)
		800
		801	Returns the previously set interval and optionally set a new one. Can be
		802	used to query the actual interval used.
		803
		804	=back
		805
		806
		807	=head3 IDLE WATCHERS - when you've got nothing better to do...
		808
		809	=over 4
351		810
352	=item $w = EV::idle $callback	811	=item $w = EV::idle $callback
353		812
354	=item $w = EV::idle_ns $callback	813	=item $w = EV::idle_ns $callback
355		814
356	Call the callback when there are no pending io, timer/periodic, signal or	815	=item $w = $loop->idle ($callback)
357	child events, i.e. when the process is idle.	816
		817	=item $w = $loop->idle_ns ($callback)
		818
		819	Call the callback when there are no other pending watchers of the same or
		820	higher priority (excluding check, prepare and other idle watchers of the
		821	same or lower priority, of course). They are called idle watchers because
		822	when the watcher is the highest priority pending event in the process, the
		823	process is considered to be idle at that priority.
		824
		825	If you want a watcher that is only ever called when I<no> other events are
		826	outstanding you have to set the priority to C<EV::MINPRI>.
358		827
359	The process will not block as long as any idle watchers are active, and	828	The process will not block as long as any idle watchers are active, and
360	they will be called repeatedly until stopped.	829	they will be called repeatedly until stopped.
361		830
		831	For example, if you have idle watchers at priority C<0> and C<1>, and
		832	an I/O watcher at priority C<0>, then the idle watcher at priority C<1>
		833	and the I/O watcher will always run when ready. Only when the idle watcher
		834	at priority C<1> is stopped and the I/O watcher at priority C<0> is not
		835	pending with the C<0>-priority idle watcher be invoked.
		836
362	The C<idle_ns> variant doesn't start (activate) the newly created watcher.	837	The C<idle_ns> variant doesn't start (activate) the newly created watcher.
363		838
		839	=back
		840
		841
		842	=head3 PREPARE WATCHERS - customise your event loop!
		843
		844	=over 4
364		845
365	=item $w = EV::prepare $callback	846	=item $w = EV::prepare $callback
366		847
367	=item $w = EV::prepare_ns $callback	848	=item $w = EV::prepare_ns $callback
		849
		850	=item $w = $loop->prepare ($callback)
		851
		852	=item $w = $loop->prepare_ns ($callback)
368		853
369	Call the callback just before the process would block. You can still	854	Call the callback just before the process would block. You can still
370	create/modify any watchers at this point.	855	create/modify any watchers at this point.
371		856
372	See the EV::check watcher, below, for explanations and an example.	857	See the EV::check watcher, below, for explanations and an example.
373		858
374	The C<prepare_ns> variant doesn't start (activate) the newly created watcher.	859	The C<prepare_ns> variant doesn't start (activate) the newly created watcher.
375		860
		861	=back
		862
		863
		864	=head3 CHECK WATCHERS - customise your event loop even more!
		865
		866	=over 4
376		867
377	=item $w = EV::check $callback	868	=item $w = EV::check $callback
378		869
379	=item $w = EV::check_ns $callback	870	=item $w = EV::check_ns $callback
		871
		872	=item $w = $loop->check ($callback)
		873
		874	=item $w = $loop->check_ns ($callback)
380		875
381	Call the callback just after the process wakes up again (after it has	876	Call the callback just after the process wakes up again (after it has
382	gathered events), but before any other callbacks have been invoked.	877	gathered events), but before any other callbacks have been invoked.
383		878
384	This is used to integrate other event-based software into the EV	879	This is used to integrate other event-based software into the EV
…		…
392	# do nothing unless active	887	# do nothing unless active
393	$dispatcher->{_event_queue_h}	888	$dispatcher->{_event_queue_h}
394	or return;	889	or return;
395		890
396	# make the dispatcher handle any outstanding stuff	891	# make the dispatcher handle any outstanding stuff
		892	... not shown
397		893
398	# create an IO watcher for each and every socket	894	# create an I/O watcher for each and every socket
399	@snmp_watcher = (	895	@snmp_watcher = (
400	(map { EV::io $_, EV::READ, sub { } }	896	(map { EV::io $_, EV::READ, sub { } }
401	keys %{ $dispatcher->{_descriptors} }),	897	keys %{ $dispatcher->{_descriptors} }),
		898
		899	EV::timer +($event->[Net::SNMP::Dispatcher::_ACTIVE]
		900	? $event->[Net::SNMP::Dispatcher::_TIME] - EV::now : 0),
		901	0, sub { },
402	);	902	);
403
404	# if there are any timeouts, also create a timer
405	push @snmp_watcher, EV::timer $event->[Net::SNMP::Dispatcher::_TIME] - EV::now, 0, sub { }
406	if $event->[Net::SNMP::Dispatcher::_ACTIVE];
407	};	903	};
408		904
409	The callbacks are irrelevant, the only purpose of those watchers is	905	The callbacks are irrelevant (and are not even being called), the
410	to wake up the process as soon as one of those events occurs (socket	906	only purpose of those watchers is to wake up the process as soon as
411	readable, or timer timed out). The corresponding EV::check watcher will then	907	one of those events occurs (socket readable, or timer timed out). The
412	clean up:	908	corresponding EV::check watcher will then clean up:
413		909
414	our $snmp_check = EV::check sub {	910	our $snmp_check = EV::check sub {
415	# destroy all watchers	911	# destroy all watchers
416	@snmp_watcher = ();	912	@snmp_watcher = ();
417		913
418	# make the dispatcher handle any new stuff	914	# make the dispatcher handle any new stuff
		915	... not shown
419	};	916	};
420		917
421	The callbacks of the created watchers will not be called as the watchers	918	The callbacks of the created watchers will not be called as the watchers
422	are destroyed before this cna happen (remember EV::check gets called	919	are destroyed before this cna happen (remember EV::check gets called
423	first).	920	first).
424		921
425	The C<check_ns> variant doesn't start (activate) the newly created watcher.	922	The C<check_ns> variant doesn't start (activate) the newly created watcher.
426		923
427	=back	924	=back
428		925
		926
		927	=head3 FORK WATCHERS - the audacity to resume the event loop after a fork
		928
		929	Fork watchers are called when a C<fork ()> was detected. The invocation
		930	is done before the event loop blocks next and before C<check> watchers
		931	are being called, and only in the child after the fork.
		932
		933	=over 4
		934
		935	=item $w = EV::fork $callback
		936
		937	=item $w = EV::fork_ns $callback
		938
		939	=item $w = $loop->fork ($callback)
		940
		941	=item $w = $loop->fork_ns ($callback)
		942
		943	Call the callback before the event loop is resumed in the child process
		944	after a fork.
		945
		946	The C<fork_ns> variant doesn't start (activate) the newly created watcher.
		947
		948	=back
		949
		950
		951	=head3 EMBED WATCHERS - when one backend isn't enough...
		952
		953	This is a rather advanced watcher type that lets you embed one event loop
		954	into another (currently only IO events are supported in the embedded
		955	loop, other types of watchers might be handled in a delayed or incorrect
		956	fashion and must not be used).
		957
		958	See the libev documentation at
		959	L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#code_ev_embed_code_when_one_backend_>
		960	for more details.
		961
		962	In short, this watcher is most useful on BSD systems without working
		963	kqueue to still be able to handle a large number of sockets:
		964
		965	my $socket_loop;
		966
		967	# check wether we use SELECT or POLL _and_ KQUEUE is supported
		968	if (
		969	(EV::backend & (EV::BACKEND_POLL \| EV::BACKEND_SELECT))
		970	&& (EV::supported_backends & EV::embeddable_backends & EV::BACKEND_KQUEUE)
		971	) {
		972	# use kqueue for sockets
		973	$socket_loop = new EV::Loop EV::BACKEND_KQUEUE \| EV::FLAG_NOENV;
		974	}
		975
		976	# use the default loop otherwise
		977	$socket_loop \|\|= EV::default_loop;
		978
		979	=over 4
		980
		981	=item $w = EV::embed $otherloop[, $callback]
		982
		983	=item $w = EV::embed_ns $otherloop[, $callback]
		984
		985	=item $w = $loop->embed ($otherloop[, $callback])
		986
		987	=item $w = $loop->embed_ns ($otherloop[, $callback])
		988
		989	Call the callback when the embedded event loop (C<$otherloop>) has any
		990	I/O activity. The C<$callback> is optional: if it is missing, then the
		991	embedded event loop will be managed automatically (which is recommended),
		992	otherwise you have to invoke C<sweep> yourself.
		993
		994	The C<embed_ns> variant doesn't start (activate) the newly created watcher.
		995
		996	=back
		997
		998	=head3 ASYNC WATCHERS - how to wake up another event loop
		999
		1000	Async watchers are provided by EV, but have little use in perl directly, as perl
		1001	neither supports threads nor direct access to signal handlers or other
		1002	contexts where they could be of value.
		1003
		1004	It is, however, possible to use them from the XS level.
		1005
		1006	Please see the libev documentation for further details.
		1007
		1008	=over 4
		1009
		1010	=item $w = EV::async $callback
		1011
		1012	=item $w = EV::async_ns $callback
		1013
		1014	=item $w->send
		1015
		1016	=item $bool = $w->async_pending
		1017
		1018	=back
		1019
		1020
		1021	=head1 PERL SIGNALS
		1022
		1023	While Perl signal handling (C<%SIG>) is not affected by EV, the behaviour
		1024	with EV is as the same as any other C library: Perl-signals will only be
		1025	handled when Perl runs, which means your signal handler might be invoked
		1026	only the next time an event callback is invoked.
		1027
		1028	The solution is to use EV signal watchers (see C<EV::signal>), which will
		1029	ensure proper operations with regards to other event watchers.
		1030
		1031	If you cannot do this for whatever reason, you can also force a watcher
		1032	to be called on every event loop iteration by installing a C<EV::check>
		1033	watcher:
		1034
		1035	my $async_check = EV::check sub { };
		1036
		1037	This ensures that perl gets into control for a short time to handle any
		1038	pending signals, and also ensures (slightly) slower overall operation.
		1039
429	=head1 THREADS	1040	=head1 THREADS
430		1041
431	Threads are not supported by this in any way. Perl pseudo-threads is evil	1042	Threads are not supported by this module in any way. Perl pseudo-threads
432	stuff and must die.	1043	is evil stuff and must die. As soon as Perl gains real threads I will work
		1044	on thread support for it.
		1045
		1046	=head1 FORK
		1047
		1048	Most of the "improved" event delivering mechanisms of modern operating
		1049	systems have quite a few problems with fork(2) (to put it bluntly: it is
		1050	not supported and usually destructive). Libev makes it possible to work
		1051	around this by having a function that recreates the kernel state after
		1052	fork in the child.
		1053
		1054	On non-win32 platforms, this module requires the pthread_atfork
		1055	functionality to do this automatically for you. This function is quite
		1056	buggy on most BSDs, though, so YMMV. The overhead for this is quite
		1057	negligible, because everything the function currently does is set a flag
		1058	that is checked only when the event loop gets used the next time, so when
		1059	you do fork but not use EV, the overhead is minimal.
		1060
		1061	On win32, there is no notion of fork so all this doesn't apply, of course.
433		1062
434	=cut	1063	=cut
435		1064
436	our $DIED = sub {	1065	our $DIED = sub {
437	warn "EV: error in callback (ignoring): $@";	1066	warn "EV: error in callback (ignoring): $@";
438	};	1067	};
439		1068
440	init;	1069	default_loop
441		1070	or die 'EV: cannot initialise libev backend. bad $ENV{LIBEV_FLAGS}?';
442	push @AnyEvent::REGISTRY, [EV => "EV::AnyEvent"];
443		1071
444	1;	1072	1;
445		1073
446	=head1 SEE ALSO	1074	=head1 SEE ALSO
447		1075
448	L<EV::DNS>, L<EV::AnyEvent>.	1076	L<EV::ADNS> (asynchronous DNS), L<Glib::EV> (makes Glib/Gtk2 use EV as
		1077	event loop), L<EV::Glib> (embed Glib into EV), L<Coro::EV> (efficient
		1078	coroutines with EV), L<Net::SNMP::EV> (asynchronous SNMP), L<AnyEvent> for
		1079	event-loop agnostic and portable event driven programming.
449		1080
450	=head1 AUTHOR	1081	=head1 AUTHOR
451		1082
452	Marc Lehmann <schmorp@schmorp.de>	1083	Marc Lehmann <schmorp@schmorp.de>
453	http://home.schmorp.de/	1084	http://home.schmorp.de/
454		1085
455	=cut	1086	=cut
456		1087

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Comparing EV/EV.pm (file contents): Revision 1.21 by root, Thu Nov 1 17:20:25 2007 UTC vs. Revision 1.101 by root, Sat Jul 12 22:19:22 2008 UTC

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Comparing EV/EV.pm (file contents):
Revision 1.21 by root, Thu Nov 1 17:20:25 2007 UTC vs.
Revision 1.101 by root, Sat Jul 12 22:19:22 2008 UTC