[ViewVC] Diff of: cvs/AnyEvent/lib/AnyEvent.pm

Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.345 by root, Fri Dec 31 04:50:44 2010 UTC vs.
Revision 1.419 by root, Thu Aug 28 15:26:20 2014 UTC

…		…
1	=head1 NAME	1	=head1 NAME
2		2
3	AnyEvent - the DBI of event loop programming	3	AnyEvent - the DBI of event loop programming
4		4
5	EV, Event, Glib, Tk, Perl, Event::Lib, Irssi, rxvt-unicode, IO::Async, Qt	5	EV, Event, Glib, Tk, UV, Perl, Event::Lib, Irssi, rxvt-unicode, IO::Async,
6	and POE are various supported event loops/environments.	6	Qt, FLTK and POE are various supported event loops/environments.
7		7
8	=head1 SYNOPSIS	8	=head1 SYNOPSIS
9		9
10	use AnyEvent;	10	use AnyEvent;
11		11
121	The interface itself is vaguely similar, but not identical to the L<Event>	121	The interface itself is vaguely similar, but not identical to the L<Event>
122	module.	122	module.
123		123
124	During the first call of any watcher-creation method, the module tries	124	During the first call of any watcher-creation method, the module tries
125	to detect the currently loaded event loop by probing whether one of the	125	to detect the currently loaded event loop by probing whether one of the
126	following modules is already loaded: L<EV>, L<AnyEvent::Impl::Perl>,	126	following modules is already loaded: L<EV>, L<AnyEvent::Loop>,
127	L<Event>, L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. The first one	127	L<Event>, L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>. The first one
128	found is used. If none are detected, the module tries to load the first	128	found is used. If none are detected, the module tries to load the first
129	four modules in the order given; but note that if L<EV> is not	129	four modules in the order given; but note that if L<EV> is not
130	available, the pure-perl L<AnyEvent::Impl::Perl> should always work, so	130	available, the pure-perl L<AnyEvent::Loop> should always work, so
131	the other two are not normally tried.	131	the other two are not normally tried.
132		132
133	Because AnyEvent first checks for modules that are already loaded, loading	133	Because AnyEvent first checks for modules that are already loaded, loading
134	an event model explicitly before first using AnyEvent will likely make	134	an event model explicitly before first using AnyEvent will likely make
135	that model the default. For example:	135	that model the default. For example:
…		…
142	The I<likely> means that, if any module loads another event model and	142	The I<likely> means that, if any module loads another event model and
143	starts using it, all bets are off - this case should be very rare though,	143	starts using it, all bets are off - this case should be very rare though,
144	as very few modules hardcode event loops without announcing this very	144	as very few modules hardcode event loops without announcing this very
145	loudly.	145	loudly.
146		146
147	The pure-perl implementation of AnyEvent is called	147	The pure-perl implementation of AnyEvent is called C<AnyEvent::Loop>. Like
148	C<AnyEvent::Impl::Perl>. Like other event modules you can load it	148	other event modules you can load it explicitly and enjoy the high
149	explicitly and enjoy the high availability of that event loop :)	149	availability of that event loop :)
150		150
151	=head1 WATCHERS	151	=head1 WATCHERS
152		152
153	AnyEvent has the central concept of a I<watcher>, which is an object that	153	AnyEvent has the central concept of a I<watcher>, which is an object that
154	stores relevant data for each kind of event you are waiting for, such as	154	stores relevant data for each kind of event you are waiting for, such as
…		…
271		271
272	Example 2: fire an event after 0.5 seconds, then roughly every second.	272	Example 2: fire an event after 0.5 seconds, then roughly every second.
273		273
274	my $w = AnyEvent->timer (after => 0.5, interval => 1, cb => sub {	274	my $w = AnyEvent->timer (after => 0.5, interval => 1, cb => sub {
275	warn "timeout\n";	275	warn "timeout\n";
276	};	276	});
277		277
278	=head3 TIMING ISSUES	278	=head3 TIMING ISSUES
279		279
280	There are two ways to handle timers: based on real time (relative, "fire	280	There are two ways to handle timers: based on real time (relative, "fire
281	in 10 seconds") and based on wallclock time (absolute, "fire at 12	281	in 10 seconds") and based on wallclock time (absolute, "fire at 12
…		…
356	difference between C<< AnyEvent->time >> and C<< AnyEvent->now >> into	356	difference between C<< AnyEvent->time >> and C<< AnyEvent->now >> into
357	account.	357	account.
358		358
359	=item AnyEvent->now_update	359	=item AnyEvent->now_update
360		360
361	Some event loops (such as L<EV> or L<AnyEvent::Impl::Perl>) cache	361	Some event loops (such as L<EV> or L<AnyEvent::Loop>) cache the current
362	the current time for each loop iteration (see the discussion of L<<	362	time for each loop iteration (see the discussion of L<< AnyEvent->now >>,
363	AnyEvent->now >>, above).	363	above).
364		364
365	When a callback runs for a long time (or when the process sleeps), then	365	When a callback runs for a long time (or when the process sleeps), then
366	this "current" time will differ substantially from the real time, which	366	this "current" time will differ substantially from the real time, which
367	might affect timers and time-outs.	367	might affect timers and time-outs.
368		368
…		…
415	not restart syscalls (that includes L<Async::Interrupt> and AnyEvent's	415	not restart syscalls (that includes L<Async::Interrupt> and AnyEvent's
416	pure perl implementation).	416	pure perl implementation).
417		417
418	=head3 Safe/Unsafe Signals	418	=head3 Safe/Unsafe Signals
419		419
420	Perl signals can be either "safe" (synchronous to opcode handling) or	420	Perl signals can be either "safe" (synchronous to opcode handling)
421	"unsafe" (asynchronous) - the former might get delayed indefinitely, the	421	or "unsafe" (asynchronous) - the former might delay signal delivery
422	latter might corrupt your memory.	422	indefinitely, the latter might corrupt your memory.
423		423
424	AnyEvent signal handlers are, in addition, synchronous to the event loop,	424	AnyEvent signal handlers are, in addition, synchronous to the event loop,
425	i.e. they will not interrupt your running perl program but will only be	425	i.e. they will not interrupt your running perl program but will only be
426	called as part of the normal event handling (just like timer, I/O etc.	426	called as part of the normal event handling (just like timer, I/O etc.
427	callbacks, too).	427	callbacks, too).
428		428
429	=head3 Signal Races, Delays and Workarounds	429	=head3 Signal Races, Delays and Workarounds
430		430
431	Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching	431	Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support
432	callbacks to signals in a generic way, which is a pity, as you cannot	432	attaching callbacks to signals in a generic way, which is a pity,
433	do race-free signal handling in perl, requiring C libraries for	433	as you cannot do race-free signal handling in perl, requiring
434	this. AnyEvent will try to do its best, which means in some cases,	434	C libraries for this. AnyEvent will try to do its best, which
435	signals will be delayed. The maximum time a signal might be delayed is	435	means in some cases, signals will be delayed. The maximum time
436	specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This	436	a signal might be delayed is 10 seconds by default, but can
437	variable can be changed only before the first signal watcher is created,	437	be overriden via C<$ENV{PERL_ANYEVENT_MAX_SIGNAL_LATENCY}> or
438	and should be left alone otherwise. This variable determines how often	438	C<$AnyEvent::MAX_SIGNAL_LATENCY> - see the L<ENVIRONMENT VARIABLES>
439	AnyEvent polls for signals (in case a wake-up was missed). Higher values	439	section for details.
440	will cause fewer spurious wake-ups, which is better for power and CPU
441	saving.
442		440
443	All these problems can be avoided by installing the optional	441	All these problems can be avoided by installing the optional
444	L<Async::Interrupt> module, which works with most event loops. It will not	442	L<Async::Interrupt> module, which works with most event loops. It will not
445	work with inherently broken event loops such as L<Event> or L<Event::Lib>	443	work with inherently broken event loops such as L<Event> or L<Event::Lib>
446	(and not with L<POE> currently, as POE does its own workaround with	444	(and not with L<POE> currently). For those, you just have to suffer the
447	one-second latency). For those, you just have to suffer the delays.	445	delays.
448		446
449	=head2 CHILD PROCESS WATCHERS	447	=head2 CHILD PROCESS WATCHERS
450		448
451	$w = AnyEvent->child (pid => <process id>, cb => <callback>);	449	$w = AnyEvent->child (pid => <process id>, cb => <callback>);
452		450
…		…
482	thing in an AnyEvent program, you I<have> to create at least one	480	thing in an AnyEvent program, you I<have> to create at least one
483	watcher before you C<fork> the child (alternatively, you can call	481	watcher before you C<fork> the child (alternatively, you can call
484	C<AnyEvent::detect>).	482	C<AnyEvent::detect>).
485		483
486	As most event loops do not support waiting for child events, they will be	484	As most event loops do not support waiting for child events, they will be
487	emulated by AnyEvent in most cases, in which the latency and race problems	485	emulated by AnyEvent in most cases, in which case the latency and race
488	mentioned in the description of signal watchers apply.	486	problems mentioned in the description of signal watchers apply.
489		487
490	Example: fork a process and wait for it	488	Example: fork a process and wait for it
491		489
492	my $done = AnyEvent->condvar;	490	my $done = AnyEvent->condvar;
493		491
		492	# this forks and immediately calls exit in the child. this
		493	# normally has all sorts of bad consequences for your parent,
		494	# so take this as an example only. always fork and exec,
		495	# or call POSIX::_exit, in real code.
494	my $pid = fork or exit 5;	496	my $pid = fork or exit 5;
495		497
496	my $w = AnyEvent->child (	498	my $w = AnyEvent->child (
497	pid => $pid,	499	pid => $pid,
498	cb => sub {	500	cb => sub {
…		…
747	This works because for every event source (EOF on file handle), there is	749	This works because for every event source (EOF on file handle), there is
748	one call to C<begin>, so the condvar waits for all calls to C<end> before	750	one call to C<begin>, so the condvar waits for all calls to C<end> before
749	sending.	751	sending.
750		752
751	The ping example mentioned above is slightly more complicated, as the	753	The ping example mentioned above is slightly more complicated, as the
752	there are results to be passwd back, and the number of tasks that are	754	there are results to be passed back, and the number of tasks that are
753	begun can potentially be zero:	755	begun can potentially be zero:
754		756
755	my $cv = AnyEvent->condvar;	757	my $cv = AnyEvent->condvar;
756		758
757	my %result;	759	my %result;
…		…
765	};	767	};
766	}	768	}
767		769
768	$cv->end;	770	$cv->end;
769		771
		772	...
		773
		774	my $results = $cv->recv;
		775
770	This code fragment supposedly pings a number of hosts and calls	776	This code fragment supposedly pings a number of hosts and calls
771	C<send> after results for all then have have been gathered - in any	777	C<send> after results for all then have have been gathered - in any
772	order. To achieve this, the code issues a call to C<begin> when it starts	778	order. To achieve this, the code issues a call to C<begin> when it starts
773	each ping request and calls C<end> when it has received some result for	779	each ping request and calls C<end> when it has received some result for
774	it. Since C<begin> and C<end> only maintain a counter, the order in which	780	it. Since C<begin> and C<end> only maintain a counter, the order in which
…		…
809		815
810	In list context, all parameters passed to C<send> will be returned,	816	In list context, all parameters passed to C<send> will be returned,
811	in scalar context only the first one will be returned.	817	in scalar context only the first one will be returned.
812		818
813	Note that doing a blocking wait in a callback is not supported by any	819	Note that doing a blocking wait in a callback is not supported by any
814	event loop, that is, recursive invocation of a blocking C<< ->recv	820	event loop, that is, recursive invocation of a blocking C<< ->recv >> is
815	>> is not allowed, and the C<recv> call will C<croak> if such a	821	not allowed and the C<recv> call will C<croak> if such a condition is
816	condition is detected. This condition can be slightly loosened by using	822	detected. This requirement can be dropped by relying on L<Coro::AnyEvent>
817	L<Coro::AnyEvent>, which allows you to do a blocking C<< ->recv >> from	823	, which allows you to do a blocking C<< ->recv >> from any thread
818	any thread that doesn't run the event loop itself.	824	that doesn't run the event loop itself. L<Coro::AnyEvent> is loaded
		825	automatically when L<Coro> is used with L<AnyEvent>, so code does not need
		826	to do anything special to take advantage of that: any code that would
		827	normally block your program because it calls C<recv>, be executed in an
		828	C<async> thread instead without blocking other threads.
819		829
820	Not all event models support a blocking wait - some die in that case	830	Not all event models support a blocking wait - some die in that case
821	(programs might want to do that to stay interactive), so I<if you are	831	(programs might want to do that to stay interactive), so I<if you are
822	using this from a module, never require a blocking wait>. Instead, let the	832	using this from a module, never require a blocking wait>. Instead, let the
823	caller decide whether the call will block or not (for example, by coupling	833	caller decide whether the call will block or not (for example, by coupling
…		…
860	use. If EV is not installed, then AnyEvent will fall back to its own	870	use. If EV is not installed, then AnyEvent will fall back to its own
861	pure-perl implementation, which is available everywhere as it comes with	871	pure-perl implementation, which is available everywhere as it comes with
862	AnyEvent itself.	872	AnyEvent itself.
863		873
864	AnyEvent::Impl::EV based on EV (interface to libev, best choice).	874	AnyEvent::Impl::EV based on EV (interface to libev, best choice).
865	AnyEvent::Impl::Perl pure-perl implementation, fast and portable.	875	AnyEvent::Impl::Perl pure-perl AnyEvent::Loop, fast and portable.
866		876
867	=item Backends that are transparently being picked up when they are used.	877	=item Backends that are transparently being picked up when they are used.
868		878
869	These will be used if they are already loaded when the first watcher	879	These will be used if they are already loaded when the first watcher
870	is created, in which case it is assumed that the application is using	880	is created, in which case it is assumed that the application is using
…		…
873	create watchers. Nothing special needs to be done by the main program.	883	create watchers. Nothing special needs to be done by the main program.
874		884
875	AnyEvent::Impl::Event based on Event, very stable, few glitches.	885	AnyEvent::Impl::Event based on Event, very stable, few glitches.
876	AnyEvent::Impl::Glib based on Glib, slow but very stable.	886	AnyEvent::Impl::Glib based on Glib, slow but very stable.
877	AnyEvent::Impl::Tk based on Tk, very broken.	887	AnyEvent::Impl::Tk based on Tk, very broken.
		888	AnyEvent::Impl::UV based on UV, innovated square wheels.
878	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.	889	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
879	AnyEvent::Impl::POE based on POE, very slow, some limitations.	890	AnyEvent::Impl::POE based on POE, very slow, some limitations.
880	AnyEvent::Impl::Irssi used when running within irssi.	891	AnyEvent::Impl::Irssi used when running within irssi.
881	AnyEvent::Impl::IOAsync based on IO::Async.	892	AnyEvent::Impl::IOAsync based on IO::Async.
882	AnyEvent::Impl::Cocoa based on Cocoa::EventLoop.	893	AnyEvent::Impl::Cocoa based on Cocoa::EventLoop.
		894	AnyEvent::Impl::FLTK based on FLTK (fltk 2 binding).
883		895
884	=item Backends with special needs.	896	=item Backends with special needs.
885		897
886	Qt requires the Qt::Application to be instantiated first, but will	898	Qt requires the Qt::Application to be instantiated first, but will
887	otherwise be picked up automatically. As long as the main program	899	otherwise be picked up automatically. As long as the main program
…		…
932		944
933	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model	945	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model
934	if necessary. You should only call this function right before you would	946	if necessary. You should only call this function right before you would
935	have created an AnyEvent watcher anyway, that is, as late as possible at	947	have created an AnyEvent watcher anyway, that is, as late as possible at
936	runtime, and not e.g. during initialisation of your module.	948	runtime, and not e.g. during initialisation of your module.
		949
		950	The effect of calling this function is as if a watcher had been created
		951	(specifically, actions that happen "when the first watcher is created"
		952	happen when calling detetc as well).
937		953
938	If you need to do some initialisation before AnyEvent watchers are	954	If you need to do some initialisation before AnyEvent watchers are
939	created, use C<post_detect>.	955	created, use C<post_detect>.
940		956
941	=item $guard = AnyEvent::post_detect { BLOCK }	957	=item $guard = AnyEvent::post_detect { BLOCK }
…		…
1004	# AnyEvent not yet initialised, so make sure to load Coro::AnyEvent	1020	# AnyEvent not yet initialised, so make sure to load Coro::AnyEvent
1005	# as soon as it is	1021	# as soon as it is
1006	push @AnyEvent::post_detect, sub { require Coro::AnyEvent };	1022	push @AnyEvent::post_detect, sub { require Coro::AnyEvent };
1007	}	1023	}
1008		1024
		1025	=item AnyEvent::postpone { BLOCK }
		1026
		1027	Arranges for the block to be executed as soon as possible, but not before
		1028	the call itself returns. In practise, the block will be executed just
		1029	before the event loop polls for new events, or shortly afterwards.
		1030
		1031	This function never returns anything (to make the C<return postpone { ...
		1032	}> idiom more useful.
		1033
		1034	To understand the usefulness of this function, consider a function that
		1035	asynchronously does something for you and returns some transaction
		1036	object or guard to let you cancel the operation. For example,
		1037	C<AnyEvent::Socket::tcp_connect>:
		1038
		1039	# start a connection attempt unless one is active
		1040	$self->{connect_guard} \|\|= AnyEvent::Socket::tcp_connect "www.example.net", 80, sub {
		1041	delete $self->{connect_guard};
		1042	...
		1043	};
		1044
		1045	Imagine that this function could instantly call the callback, for
		1046	example, because it detects an obvious error such as a negative port
		1047	number. Invoking the callback before the function returns causes problems
		1048	however: the callback will be called and will try to delete the guard
		1049	object. But since the function hasn't returned yet, there is nothing to
		1050	delete. When the function eventually returns it will assign the guard
		1051	object to C<< $self->{connect_guard} >>, where it will likely never be
		1052	deleted, so the program thinks it is still trying to connect.
		1053
		1054	This is where C<AnyEvent::postpone> should be used. Instead of calling the
		1055	callback directly on error:
		1056
		1057	$cb->(undef), return # signal error to callback, BAD!
		1058	if $some_error_condition;
		1059
		1060	It should use C<postpone>:
		1061
		1062	AnyEvent::postpone { $cb->(undef) }, return # signal error to callback, later
		1063	if $some_error_condition;
		1064
		1065	=item AnyEvent::log $level, $msg[, @args]
		1066
		1067	Log the given C<$msg> at the given C<$level>.
		1068
		1069	If L<AnyEvent::Log> is not loaded then this function makes a simple test
		1070	to see whether the message will be logged. If the test succeeds it will
		1071	load AnyEvent::Log and call C<AnyEvent::Log::log> - consequently, look at
		1072	the L<AnyEvent::Log> documentation for details.
		1073
		1074	If the test fails it will simply return. Right now this happens when a
		1075	numerical loglevel is used and it is larger than the level specified via
		1076	C<$ENV{PERL_ANYEVENT_VERBOSE}>.
		1077
		1078	If you want to sprinkle loads of logging calls around your code, consider
		1079	creating a logger callback with the C<AnyEvent::Log::logger> function,
		1080	which can reduce typing, codesize and can reduce the logging overhead
		1081	enourmously.
		1082
1009	=back	1083	=back
1010		1084
1011	=head1 WHAT TO DO IN A MODULE	1085	=head1 WHAT TO DO IN A MODULE
1012		1086
1013	As a module author, you should C<use AnyEvent> and call AnyEvent methods	1087	As a module author, you should C<use AnyEvent> and call AnyEvent methods
…		…
1046	modules might create watchers when they are loaded, and AnyEvent will	1120	modules might create watchers when they are loaded, and AnyEvent will
1047	decide on the event model to use as soon as it creates watchers, and it	1121	decide on the event model to use as soon as it creates watchers, and it
1048	might choose the wrong one unless you load the correct one yourself.	1122	might choose the wrong one unless you load the correct one yourself.
1049		1123
1050	You can chose to use a pure-perl implementation by loading the	1124	You can chose to use a pure-perl implementation by loading the
1051	C<AnyEvent::Impl::Perl> module, which gives you similar behaviour	1125	C<AnyEvent::Loop> module, which gives you similar behaviour
1052	everywhere, but letting AnyEvent chose the model is generally better.	1126	everywhere, but letting AnyEvent chose the model is generally better.
1053		1127
1054	=head2 MAINLOOP EMULATION	1128	=head2 MAINLOOP EMULATION
1055		1129
1056	Sometimes (often for short test scripts, or even standalone programs who	1130	Sometimes (often for short test scripts, or even standalone programs who
…		…
1069		1143
1070		1144
1071	=head1 OTHER MODULES	1145	=head1 OTHER MODULES
1072		1146
1073	The following is a non-exhaustive list of additional modules that use	1147	The following is a non-exhaustive list of additional modules that use
1074	AnyEvent as a client and can therefore be mixed easily with other AnyEvent	1148	AnyEvent as a client and can therefore be mixed easily with other
1075	modules and other event loops in the same program. Some of the modules	1149	AnyEvent modules and other event loops in the same program. Some of the
1076	come as part of AnyEvent, the others are available via CPAN.	1150	modules come as part of AnyEvent, the others are available via CPAN (see
		1151	L<http://search.cpan.org/search?m=module&q=anyevent%3A%3A*> for
		1152	a longer non-exhaustive list), and the list is heavily biased towards
		1153	modules of the AnyEvent author himself :)
1077		1154
1078	=over 4	1155	=over 4
1079		1156
1080	=item L<AnyEvent::Util>	1157	=item L<AnyEvent::Util> (part of the AnyEvent distribution)
1081		1158
1082	Contains various utility functions that replace often-used blocking	1159	Contains various utility functions that replace often-used blocking
1083	functions such as C<inet_aton> with event/callback-based versions.	1160	functions such as C<inet_aton> with event/callback-based versions.
1084		1161
1085	=item L<AnyEvent::Socket>	1162	=item L<AnyEvent::Socket> (part of the AnyEvent distribution)
1086		1163
1087	Provides various utility functions for (internet protocol) sockets,	1164	Provides various utility functions for (internet protocol) sockets,
1088	addresses and name resolution. Also functions to create non-blocking tcp	1165	addresses and name resolution. Also functions to create non-blocking tcp
1089	connections or tcp servers, with IPv6 and SRV record support and more.	1166	connections or tcp servers, with IPv6 and SRV record support and more.
1090		1167
1091	=item L<AnyEvent::Handle>	1168	=item L<AnyEvent::Handle> (part of the AnyEvent distribution)
1092		1169
1093	Provide read and write buffers, manages watchers for reads and writes,	1170	Provide read and write buffers, manages watchers for reads and writes,
1094	supports raw and formatted I/O, I/O queued and fully transparent and	1171	supports raw and formatted I/O, I/O queued and fully transparent and
1095	non-blocking SSL/TLS (via L<AnyEvent::TLS>).	1172	non-blocking SSL/TLS (via L<AnyEvent::TLS>).
1096		1173
1097	=item L<AnyEvent::DNS>	1174	=item L<AnyEvent::DNS> (part of the AnyEvent distribution)
1098		1175
1099	Provides rich asynchronous DNS resolver capabilities.	1176	Provides rich asynchronous DNS resolver capabilities.
1100		1177
1101	=item L<AnyEvent::HTTP>, L<AnyEvent::IRC>, L<AnyEvent::XMPP>, L<AnyEvent::GPSD>, L<AnyEvent::IGS>, L<AnyEvent::FCP>	1178	=item L<AnyEvent::HTTP>, L<AnyEvent::IRC>, L<AnyEvent::XMPP>, L<AnyEvent::GPSD>, L<AnyEvent::IGS>, L<AnyEvent::FCP>
1102		1179
1103	Implement event-based interfaces to the protocols of the same name (for	1180	Implement event-based interfaces to the protocols of the same name (for
1104	the curious, IGS is the International Go Server and FCP is the Freenet	1181	the curious, IGS is the International Go Server and FCP is the Freenet
1105	Client Protocol).	1182	Client Protocol).
1106		1183
1107	=item L<AnyEvent::Handle::UDP>	1184	=item L<AnyEvent::AIO> (part of the AnyEvent distribution)
1108
1109	Here be danger!
1110
1111	As Pauli would put it, "Not only is it not right, it's not even wrong!" -
1112	there are so many things wrong with AnyEvent::Handle::UDP, most notably
1113	its use of a stream-based API with a protocol that isn't streamable, that
1114	the only way to improve it is to delete it.
1115
1116	It features data corruption (but typically only under load) and general
1117	confusion. On top, the author is not only clueless about UDP but also
1118	fact-resistant - some gems of his understanding: "connect doesn't work
1119	with UDP", "UDP packets are not IP packets", "UDP only has datagrams, not
1120	packets", "I don't need to implement proper error checking as UDP doesn't
1121	support error checking" and so on - he doesn't even understand what's
1122	wrong with his module when it is explained to him.
1123
1124	=item L<AnyEvent::DBI>
1125
1126	Executes L<DBI> requests asynchronously in a proxy process for you,
1127	notifying you in an event-based way when the operation is finished.
1128
1129	=item L<AnyEvent::AIO>
1130		1185
1131	Truly asynchronous (as opposed to non-blocking) I/O, should be in the	1186	Truly asynchronous (as opposed to non-blocking) I/O, should be in the
1132	toolbox of every event programmer. AnyEvent::AIO transparently fuses	1187	toolbox of every event programmer. AnyEvent::AIO transparently fuses
1133	L<IO::AIO> and AnyEvent together, giving AnyEvent access to event-based	1188	L<IO::AIO> and AnyEvent together, giving AnyEvent access to event-based
1134	file I/O, and much more.	1189	file I/O, and much more.
1135		1190
		1191	=item L<AnyEvent::Fork>, L<AnyEvent::Fork::RPC>, L<AnyEvent::Fork::Pool>, L<AnyEvent::Fork::Remote>
		1192
		1193	These let you safely fork new subprocesses, either locally or
		1194	remotely (e.g.v ia ssh), using some RPC protocol or not, without
		1195	the limitations normally imposed by fork (AnyEvent works fine for
		1196	example). Dynamically-resized worker pools are obviously included as well.
		1197
		1198	And they are quite tiny and fast as well - "abusing" L<AnyEvent::Fork>
		1199	just to exec external programs can easily beat using C<fork> and C<exec>
		1200	(or even C<system>) in most programs.
		1201
		1202	=item L<AnyEvent::Filesys::Notify>
		1203
		1204	AnyEvent is good for non-blocking stuff, but it can't detect file or
		1205	path changes (e.g. "watch this directory for new files", "watch this
		1206	file for changes"). The L<AnyEvent::Filesys::Notify> module promises to
		1207	do just that in a portbale fashion, supporting inotify on GNU/Linux and
		1208	some weird, without doubt broken, stuff on OS X to monitor files. It can
		1209	fall back to blocking scans at regular intervals transparently on other
		1210	platforms, so it's about as portable as it gets.
		1211
		1212	(I haven't used it myself, but it seems the biggest problem with it is
		1213	it quite bad performance).
		1214
1136	=item L<AnyEvent::HTTPD>	1215	=item L<AnyEvent::DBI>
1137		1216
1138	A simple embedded webserver.	1217	Executes L<DBI> requests asynchronously in a proxy process for you,
		1218	notifying you in an event-based way when the operation is finished.
1139		1219
1140	=item L<AnyEvent::FastPing>	1220	=item L<AnyEvent::FastPing>
1141		1221
1142	The fastest ping in the west.	1222	The fastest ping in the west.
1143		1223
1144	=item L<Coro>	1224	=item L<Coro>
1145		1225
1146	Has special support for AnyEvent via L<Coro::AnyEvent>.	1226	Has special support for AnyEvent via L<Coro::AnyEvent>, which allows you
		1227	to simply invert the flow control - don't call us, we will call you:
		1228
		1229	async {
		1230	Coro::AnyEvent::sleep 5; # creates a 5s timer and waits for it
		1231	print "5 seconds later!\n";
		1232
		1233	Coro::AnyEvent::readable *STDIN; # uses an I/O watcher
		1234	my $line = <STDIN>; # works for ttys
		1235
		1236	AnyEvent::HTTP::http_get "url", Coro::rouse_cb;
		1237	my ($body, $hdr) = Coro::rouse_wait;
		1238	};
1147		1239
1148	=back	1240	=back
1149		1241
1150	=cut	1242	=cut
1151		1243
1152	package AnyEvent;	1244	package AnyEvent;
1153
1154	# basically a tuned-down version of common::sense
1155	sub common_sense {
1156	# from common:.sense 3.3
1157	${^WARNING_BITS} ^= ${^WARNING_BITS} ^ "\x3c\x3f\x33\x00\x0f\xf3\x0f\xc0\xf0\xfc\x33\x00";
1158	# use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl)
1159	$^H \|= 0x00000600;
1160	}
1161
1162	BEGIN { AnyEvent::common_sense }
1163
1164	use Carp ();
1165
1166	our $VERSION = '5.3';
1167	our $MODEL;
1168
1169	our $AUTOLOAD;
1170	our @ISA;
1171
1172	our @REGISTRY;
1173
1174	our $VERBOSE;
1175		1245
1176	BEGIN {	1246	BEGIN {
1177	require "AnyEvent/constants.pl";	1247	require "AnyEvent/constants.pl";
		1248	&AnyEvent::common_sense;
		1249	}
1178		1250
		1251	use Carp ();
		1252
		1253	our $VERSION = '7.07';
		1254	our $MODEL;
		1255	our @ISA;
		1256	our @REGISTRY;
		1257	our $VERBOSE;
		1258	our %PROTOCOL; # (ipv4\|ipv6) => (1\|2), higher numbers are preferred
		1259	our $MAX_SIGNAL_LATENCY = $ENV{PERL_ANYEVENT_MAX_SIGNAL_LATENCY} \|\| 10; # executes after the BEGIN block below (tainting!)
		1260
		1261	BEGIN {
1179	eval "sub TAINT (){" . (${^TAINT}*1) . "}";	1262	eval "sub TAINT (){" . (${^TAINT}*1) . "}";
1180		1263
1181	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}	1264	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}
1182	if ${^TAINT};	1265	if ${^TAINT};
1183		1266
1184	$VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1;	1267	$ENV{"PERL_ANYEVENT_$_"} = $ENV{"AE_$_"}
		1268	for grep s/^AE_// && !exists $ENV{"PERL_ANYEVENT_$_"}, keys %ENV;
1185		1269
1186	}	1270	@ENV{grep /^PERL_ANYEVENT_/, keys %ENV} = ()
		1271	if ${^TAINT};
1187		1272
1188	our $MAX_SIGNAL_LATENCY = 10;	1273	# $ENV{PERL_ANYEVENT_xxx} now valid
1189		1274
1190	our %PROTOCOL; # (ipv4\|ipv6) => (1\|2), higher numbers are preferred	1275	$VERBOSE = length $ENV{PERL_ANYEVENT_VERBOSE} ? $ENV{PERL_ANYEVENT_VERBOSE}*1 : 4;
1191		1276
1192	{
1193	my $idx;	1277	my $idx;
1194	$PROTOCOL{$_} = ++$idx	1278	$PROTOCOL{$_} = ++$idx
1195	for reverse split /\s,\s/,	1279	for reverse split /\s,\s/,
1196	$ENV{PERL_ANYEVENT_PROTOCOLS} \|\| "ipv4,ipv6";	1280	$ENV{PERL_ANYEVENT_PROTOCOLS} \|\| "ipv4,ipv6";
1197	}	1281	}
1198		1282
		1283	our @post_detect;
		1284
		1285	sub post_detect(&) {
		1286	my ($cb) = @_;
		1287
		1288	push @post_detect, $cb;
		1289
		1290	defined wantarray
		1291	? bless \$cb, "AnyEvent::Util::postdetect"
		1292	: ()
		1293	}
		1294
		1295	sub AnyEvent::Util::postdetect::DESTROY {
		1296	@post_detect = grep $_ != ${$_[0]}, @post_detect;
		1297	}
		1298
		1299	our $POSTPONE_W;
		1300	our @POSTPONE;
		1301
		1302	sub _postpone_exec {
		1303	undef $POSTPONE_W;
		1304
		1305	&{ shift @POSTPONE }
		1306	while @POSTPONE;
		1307	}
		1308
		1309	sub postpone(&) {
		1310	push @POSTPONE, shift;
		1311
		1312	$POSTPONE_W \|\|= AE::timer (0, 0, \&_postpone_exec);
		1313
		1314	()
		1315	}
		1316
		1317	sub log($$;@) {
		1318	# only load the big bloated module when we actually are about to log something
		1319	if ($_[0] <= ($VERBOSE \|\| 1)) { # also catches non-numeric levels(!) and fatal
		1320	local ($!, $@);
		1321	require AnyEvent::Log; # among other things, sets $VERBOSE to 9
		1322	# AnyEvent::Log overwrites this function
		1323	goto &log;
		1324	}
		1325
		1326	0 # not logged
		1327	}
		1328
		1329	sub _logger($;$) {
		1330	my ($level, $renabled) = @_;
		1331
		1332	$$renabled = $level <= $VERBOSE;
		1333
		1334	my $logger = [(caller)[0], $level, $renabled];
		1335
		1336	$AnyEvent::Log::LOGGER{$logger+0} = $logger;
		1337
		1338	# return unless defined wantarray;
		1339	#
		1340	# require AnyEvent::Util;
		1341	# my $guard = AnyEvent::Util::guard (sub {
		1342	# # "clean up"
		1343	# delete $LOGGER{$logger+0};
		1344	# });
		1345	#
		1346	# sub {
		1347	# return 0 unless $$renabled;
		1348	#
		1349	# $guard if 0; # keep guard alive, but don't cause runtime overhead
		1350	# require AnyEvent::Log unless $AnyEvent::Log::VERSION;
		1351	# package AnyEvent::Log;
		1352	# _log ($logger->[0], $level, @_) # logger->[0] has been converted at load time
		1353	# }
		1354	}
		1355
		1356	if (length $ENV{PERL_ANYEVENT_LOG}) {
		1357	require AnyEvent::Log; # AnyEvent::Log does the thing for us
		1358	}
		1359
1199	my @models = (	1360	our @models = (
1200	[EV:: => AnyEvent::Impl::EV:: , 1],	1361	[EV:: => AnyEvent::Impl::EV::],
1201	[AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl:: , 1],	1362	[AnyEvent::Loop:: => AnyEvent::Impl::Perl::],
1202	# everything below here will not (normally) be autoprobed	1363	# everything below here will not (normally) be autoprobed
1203	# as the pureperl backend should work everywhere	1364	# as the pure perl backend should work everywhere
1204	# and is usually faster	1365	# and is usually faster
		1366	[Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package, so msut be near the top
1205	[Event:: => AnyEvent::Impl::Event::, 1],	1367	[Event:: => AnyEvent::Impl::Event::], # slow, stable
1206	[Glib:: => AnyEvent::Impl::Glib:: , 1], # becomes extremely slow with many watchers	1368	[Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers
		1369	# everything below here should not be autoloaded
1207	[Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy	1370	[Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
1208	[Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package
1209	[Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles	1371	[Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
		1372	[UV:: => AnyEvent::Impl::UV::], # switched from libev, added back all bugs imaginable
1210	[Qt:: => AnyEvent::Impl::Qt::], # requires special main program	1373	[Qt:: => AnyEvent::Impl::Qt::], # requires special main program
1211	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza	1374	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
1212	[Wx:: => AnyEvent::Impl::POE::],	1375	[Wx:: => AnyEvent::Impl::POE::],
1213	[Prima:: => AnyEvent::Impl::POE::],	1376	[Prima:: => AnyEvent::Impl::POE::],
1214	[IO::Async::Loop:: => AnyEvent::Impl::IOAsync::],	1377	[IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # a bitch to autodetect
1215	[Cocoa::EventLoop:: => AnyEvent::Impl::Cocoa::],	1378	[Cocoa::EventLoop:: => AnyEvent::Impl::Cocoa::],
		1379	[FLTK:: => AnyEvent::Impl::FLTK::],
1216	);	1380	);
1217		1381
1218	our %method = map +($_ => 1),	1382	our @isa_hook;
		1383
		1384	sub _isa_set {
		1385	my @pkg = ("AnyEvent", (map $_->[0], grep defined, @isa_hook), $MODEL);
		1386
		1387	@{"$pkg[$_-1]::ISA"} = $pkg[$_]
		1388	for 1 .. $#pkg;
		1389
		1390	grep $_ && $_->[1], @isa_hook
		1391	and AE::_reset ();
		1392	}
		1393
		1394	# used for hooking AnyEvent::Strict and AnyEvent::Debug::Wrap into the class hierarchy
		1395	sub _isa_hook($$;$) {
		1396	my ($i, $pkg, $reset_ae) = @_;
		1397
		1398	$isa_hook[$i] = $pkg ? [$pkg, $reset_ae] : undef;
		1399
		1400	_isa_set;
		1401	}
		1402
		1403	# all autoloaded methods reserve the complete glob, not just the method slot.
		1404	# due to bugs in perls method cache implementation.
1219	qw(io timer time now now_update signal child idle condvar one_event DESTROY);	1405	our @methods = qw(io timer time now now_update signal child idle condvar);
1220
1221	our @post_detect;
1222
1223	sub post_detect(&) {
1224	my ($cb) = @_;
1225
1226	push @post_detect, $cb;
1227
1228	defined wantarray
1229	? bless \$cb, "AnyEvent::Util::postdetect"
1230	: ()
1231	}
1232
1233	sub AnyEvent::Util::postdetect::DESTROY {
1234	@post_detect = grep $_ != ${$_[0]}, @post_detect;
1235	}
1236		1406
1237	sub detect() {	1407	sub detect() {
		1408	return $MODEL if $MODEL; # some programs keep references to detect
		1409
		1410	# IO::Async::Loop::AnyEvent is extremely evil, refuse to work with it
		1411	# the author knows about the problems and what it does to AnyEvent as a whole
		1412	# (and the ability of others to use AnyEvent), but simply wants to abuse AnyEvent
		1413	# anyway.
		1414	AnyEvent::log fatal => "IO::Async::Loop::AnyEvent detected - that module is broken by\n"
		1415	. "design, abuses internals and breaks AnyEvent - will not continue."
		1416	if exists $INC{"IO/Async/Loop/AnyEvent.pm"};
		1417
		1418	local $!; # for good measure
		1419	local $SIG{__DIE__}; # we use eval
		1420
1238	# free some memory	1421	# free some memory
1239	*detect = sub () { $MODEL };	1422	*detect = sub () { $MODEL };
		1423	# undef &func doesn't correctly update the method cache. grmbl.
		1424	# so we delete the whole glob. grmbl.
		1425	# otoh, perl doesn't let me undef an active usb, but it lets me free
		1426	# a glob with an active sub. hrm. i hope it works, but perl is
		1427	# usually buggy in this department. sigh.
		1428	delete @{"AnyEvent::"}{@methods};
		1429	undef @methods;
1240		1430
1241	local $!; # for good measure
1242	local $SIG{__DIE__};
1243
1244	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {	1431	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z0-9:]+)$/) {
1245	my $model = "AnyEvent::Impl::$1";	1432	my $model = $1;
		1433	$model = "AnyEvent::Impl::$model" unless $model =~ s/::$//;
1246	if (eval "require $model") {	1434	if (eval "require $model") {
		1435	AnyEvent::log 7 => "Loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.";
1247	$MODEL = $model;	1436	$MODEL = $model;
1248	warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2;
1249	} else {	1437	} else {
1250	warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE;	1438	AnyEvent::log 4 => "Unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@";
1251	}	1439	}
1252	}	1440	}
1253		1441
1254	# check for already loaded models	1442	# check for already loaded models
1255	unless ($MODEL) {	1443	unless ($MODEL) {
1256	for (@REGISTRY, @models) {	1444	for (@REGISTRY, @models) {
1257	my ($package, $model) = @$_;	1445	my ($package, $model) = @$_;
1258	if (${"$package\::VERSION"} > 0) {	1446	if (${"$package\::VERSION"} > 0) {
1259	if (eval "require $model") {	1447	if (eval "require $model") {
		1448	AnyEvent::log 7 => "Autodetected model '$model', using it.";
1260	$MODEL = $model;	1449	$MODEL = $model;
1261	warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2;	1450	last;
		1451	} else {
		1452	AnyEvent::log 8 => "Detected event loop $package, but cannot load '$model', skipping: $@";
		1453	}
		1454	}
		1455	}
		1456
		1457	unless ($MODEL) {
		1458	# try to autoload a model
		1459	for (@REGISTRY, @models) {
		1460	my ($package, $model) = @$_;
		1461	if (
		1462	eval "require $package"
		1463	and ${"$package\::VERSION"} > 0
		1464	and eval "require $model"
		1465	) {
		1466	AnyEvent::log 7 => "Autoloaded model '$model', using it.";
		1467	$MODEL = $model;
1262	last;	1468	last;
1263	}	1469	}
1264	}	1470	}
1265	}
1266
1267	unless ($MODEL) {
1268	# try to autoload a model
1269	for (@REGISTRY, @models) {
1270	my ($package, $model, $autoload) = @$_;
1271	if (
1272	$autoload
1273	and eval "require $package"
1274	and ${"$package\::VERSION"} > 0
1275	and eval "require $model"
1276	) {
1277	$MODEL = $model;
1278	warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2;
1279	last;
1280	}
1281	}
1282		1471
1283	$MODEL	1472	$MODEL
1284	or die "AnyEvent: backend autodetection failed - did you properly install AnyEvent?\n";	1473	or AnyEvent::log fatal => "Backend autodetection failed - did you properly install AnyEvent?";
1285	}	1474	}
1286	}	1475	}
1287		1476
1288	@models = (); # free probe data	1477	# free memory only needed for probing
		1478	undef @models;
		1479	undef @REGISTRY;
1289		1480
1290	push @{"$MODEL\::ISA"}, "AnyEvent::Base";	1481	push @{"$MODEL\::ISA"}, "AnyEvent::Base";
1291	unshift @ISA, $MODEL;
1292		1482
1293	# now nuke some methods that are overridden by the backend.	1483	# now nuke some methods that are overridden by the backend.
1294	# SUPER is not allowed.	1484	# SUPER usage is not allowed in these.
1295	for (qw(time signal child idle)) {	1485	for (qw(time signal child idle)) {
1296	undef &{"AnyEvent::Base::$_"}	1486	undef &{"AnyEvent::Base::$_"}
1297	if defined &{"$MODEL\::$_"};	1487	if defined &{"$MODEL\::$_"};
1298	}	1488	}
1299		1489
		1490	_isa_set;
		1491
		1492	# we're officially open!
		1493
1300	if ($ENV{PERL_ANYEVENT_STRICT}) {	1494	if ($ENV{PERL_ANYEVENT_STRICT}) {
1301	eval { require AnyEvent::Strict };	1495	require AnyEvent::Strict;
1302	warn "AnyEvent: cannot load AnyEvent::Strict: $@"
1303	if $@ && $VERBOSE;
1304	}	1496	}
1305		1497
		1498	if ($ENV{PERL_ANYEVENT_DEBUG_WRAP}) {
		1499	require AnyEvent::Debug;
		1500	AnyEvent::Debug::wrap ($ENV{PERL_ANYEVENT_DEBUG_WRAP});
		1501	}
		1502
		1503	if (length $ENV{PERL_ANYEVENT_DEBUG_SHELL}) {
		1504	require AnyEvent::Socket;
		1505	require AnyEvent::Debug;
		1506
		1507	my $shell = $ENV{PERL_ANYEVENT_DEBUG_SHELL};
		1508	$shell =~ s/\$\$/$$/g;
		1509
		1510	my ($host, $service) = AnyEvent::Socket::parse_hostport ($shell);
		1511	$AnyEvent::Debug::SHELL = AnyEvent::Debug::shell ($host, $service);
		1512	}
		1513
		1514	# now the anyevent environment is set up as the user told us to, so
		1515	# call the actual user code - post detects
		1516
1306	(shift @post_detect)->() while @post_detect;	1517	(shift @post_detect)->() while @post_detect;
		1518	undef @post_detect;
1307		1519
1308	*post_detect = sub(&) {	1520	*post_detect = sub(&) {
1309	shift->();	1521	shift->();
1310		1522
1311	undef	1523	undef
1312	};	1524	};
1313		1525
1314	$MODEL	1526	$MODEL
1315	}	1527	}
1316		1528
1317	sub AUTOLOAD {	1529	for my $name (@methods) {
1318	(my $func = $AUTOLOAD) =~ s/.*://;	1530	*$name = sub {
1319
1320	$method{$func}
1321	or Carp::croak "$func: not a valid AnyEvent class method";
1322
1323	detect;	1531	detect;
1324		1532	# we use goto because
1325	my $class = shift;	1533	# a) it makes the thunk more transparent
1326	$class->$func (@_);	1534	# b) it allows us to delete the thunk later
		1535	goto &{ UNIVERSAL::can AnyEvent => "SUPER::$name" }
		1536	};
1327	}	1537	}
1328		1538
1329	# utility function to dup a filehandle. this is used by many backends	1539	# utility function to dup a filehandle. this is used by many backends
1330	# to support binding more than one watcher per filehandle (they usually	1540	# to support binding more than one watcher per filehandle (they usually
1331	# allow only one watcher per fd, so we dup it to get a different one).	1541	# allow only one watcher per fd, so we dup it to get a different one).
…		…
1355		1565
1356	package AE;	1566	package AE;
1357		1567
1358	our $VERSION = $AnyEvent::VERSION;	1568	our $VERSION = $AnyEvent::VERSION;
1359		1569
		1570	sub _reset() {
		1571	eval q{
1360	# fall back to the main API by default - backends and AnyEvent::Base	1572	# fall back to the main API by default - backends and AnyEvent::Base
1361	# implementations can overwrite these.	1573	# implementations can overwrite these.
1362		1574
1363	sub io($$$) {	1575	sub io($$$) {
1364	AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])	1576	AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])
1365	}	1577	}
1366		1578
1367	sub timer($$$) {	1579	sub timer($$$) {
1368	AnyEvent->timer (after => $_[0], interval => $_[1], cb => $_[2])	1580	AnyEvent->timer (after => $_[0], interval => $_[1], cb => $_[2])
1369	}	1581	}
1370		1582
1371	sub signal($$) {	1583	sub signal($$) {
1372	AnyEvent->signal (signal => $_[0], cb => $_[1])	1584	AnyEvent->signal (signal => $_[0], cb => $_[1])
1373	}	1585	}
1374		1586
1375	sub child($$) {	1587	sub child($$) {
1376	AnyEvent->child (pid => $_[0], cb => $_[1])	1588	AnyEvent->child (pid => $_[0], cb => $_[1])
1377	}	1589	}
1378		1590
1379	sub idle($) {	1591	sub idle($) {
1380	AnyEvent->idle (cb => $_[0])	1592	AnyEvent->idle (cb => $_[0]);
1381	}	1593	}
1382		1594
1383	sub cv(;&) {	1595	sub cv(;&) {
1384	AnyEvent->condvar (@_ ? (cb => $_[0]) : ())	1596	AnyEvent->condvar (@_ ? (cb => $_[0]) : ())
1385	}	1597	}
1386		1598
1387	sub now() {	1599	sub now() {
1388	AnyEvent->now	1600	AnyEvent->now
1389	}	1601	}
1390		1602
1391	sub now_update() {	1603	sub now_update() {
1392	AnyEvent->now_update	1604	AnyEvent->now_update
1393	}	1605	}
1394		1606
1395	sub time() {	1607	sub time() {
1396	AnyEvent->time	1608	AnyEvent->time
		1609	}
		1610
		1611	*postpone = \&AnyEvent::postpone;
		1612	*log = \&AnyEvent::log;
		1613	};
		1614	die if $@;
1397	}	1615	}
		1616
		1617	BEGIN { _reset }
1398		1618
1399	package AnyEvent::Base;	1619	package AnyEvent::Base;
1400		1620
1401	# default implementations for many methods	1621	# default implementations for many methods
1402		1622
1403	sub time {	1623	sub time {
1404	eval q{ # poor man's autoloading {}	1624	eval q{ # poor man's autoloading {}
1405	# probe for availability of Time::HiRes	1625	# probe for availability of Time::HiRes
1406	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {	1626	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
1407	warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8;	1627	*time = sub { Time::HiRes::time () };
1408	*AE::time = \&Time::HiRes::time;	1628	*AE::time = \& Time::HiRes::time ;
		1629	*now = \&time;
		1630	AnyEvent::log 8 => "using Time::HiRes for sub-second timing accuracy.";
1409	# if (eval "use POSIX (); (POSIX::times())...	1631	# if (eval "use POSIX (); (POSIX::times())...
1410	} else {	1632	} else {
1411	warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE;	1633	*time = sub { CORE::time };
1412	*AE::time = sub (){ time }; # epic fail	1634	*AE::time = sub (){ CORE::time };
		1635	*now = \&time;
		1636	AnyEvent::log 3 => "Using built-in time(), no sub-second resolution!";
1413	}	1637	}
1414
1415	*time = sub { AE::time }; # different prototypes
1416	};	1638	};
1417	die if $@;	1639	die if $@;
1418		1640
1419	&time	1641	&time
1420	}	1642	}
1421		1643
1422	*now = \&time;	1644	*now = \&time;
1423
1424	sub now_update { }	1645	sub now_update { }
1425		1646
		1647	sub _poll {
		1648	Carp::croak "$AnyEvent::MODEL does not support blocking waits. Caught";
		1649	}
		1650
1426	# default implementation for ->condvar	1651	# default implementation for ->condvar
		1652	# in fact, the default should not be overwritten
1427		1653
1428	sub condvar {	1654	sub condvar {
1429	eval q{ # poor man's autoloading {}	1655	eval q{ # poor man's autoloading {}
1430	*condvar = sub {	1656	*condvar = sub {
1431	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"	1657	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"
…		…
1509		1735
1510	sub signal {	1736	sub signal {
1511	eval q{ # poor man's autoloading {}	1737	eval q{ # poor man's autoloading {}
1512	# probe for availability of Async::Interrupt	1738	# probe for availability of Async::Interrupt
1513	if (_have_async_interrupt) {	1739	if (_have_async_interrupt) {
1514	warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8;	1740	AnyEvent::log 8 => "Using Async::Interrupt for race-free signal handling.";
1515		1741
1516	$SIGPIPE_R = new Async::Interrupt::EventPipe;	1742	$SIGPIPE_R = new Async::Interrupt::EventPipe;
1517	$SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;	1743	$SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;
1518		1744
1519	} else {	1745	} else {
1520	warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;	1746	AnyEvent::log 8 => "Using emulated perl signal handling with latency timer.";
1521		1747
1522	if (AnyEvent::WIN32) {	1748	if (AnyEvent::WIN32) {
1523	require AnyEvent::Util;	1749	require AnyEvent::Util;
1524		1750
1525	($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();	1751	($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
…		…
1601	: sysread $SIGPIPE_R, (my $dummy), 9;	1827	: sysread $SIGPIPE_R, (my $dummy), 9;
1602		1828
1603	while (%SIG_EV) {	1829	while (%SIG_EV) {
1604	for (keys %SIG_EV) {	1830	for (keys %SIG_EV) {
1605	delete $SIG_EV{$_};	1831	delete $SIG_EV{$_};
1606	$_->() for values %{ $SIG_CB{$_} \|\| {} };	1832	&$_ for values %{ $SIG_CB{$_} \|\| {} };
1607	}	1833	}
1608	}	1834	}
1609	};	1835	};
1610	};	1836	};
1611	die if $@;	1837	die if $@;
…		…
1638	};	1864	};
1639		1865
1640	*child = sub {	1866	*child = sub {
1641	my (undef, %arg) = @_;	1867	my (undef, %arg) = @_;
1642		1868
1643	defined (my $pid = $arg{pid} + 0)	1869	my $pid = $arg{pid};
1644	or Carp::croak "required option 'pid' is missing";	1870	my $cb = $arg{cb};
1645		1871
1646	$PID_CB{$pid}{$arg{cb}} = $arg{cb};	1872	$PID_CB{$pid}{$cb+0} = $cb;
1647		1873
1648	unless ($CHLD_W) {	1874	unless ($CHLD_W) {
1649	$CHLD_W = AE::signal CHLD => \&_sigchld;	1875	$CHLD_W = AE::signal CHLD => \&_sigchld;
1650	# child could be a zombie already, so make at least one round	1876	# child could be a zombie already, so make at least one round
1651	&_sigchld;	1877	&_sigchld;
1652	}	1878	}
1653		1879
1654	bless [$pid, $arg{cb}], "AnyEvent::Base::child"	1880	bless [$pid, $cb+0], "AnyEvent::Base::child"
1655	};	1881	};
1656		1882
1657	*AnyEvent::Base::child::DESTROY = sub {	1883	*AnyEvent::Base::child::DESTROY = sub {
1658	my ($pid, $cb) = @{$_[0]};	1884	my ($pid, $icb) = @{$_[0]};
1659		1885
1660	delete $PID_CB{$pid}{$cb};	1886	delete $PID_CB{$pid}{$icb};
1661	delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };	1887	delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };
1662		1888
1663	undef $CHLD_W unless keys %PID_CB;	1889	undef $CHLD_W unless keys %PID_CB;
1664	};	1890	};
1665	};	1891	};
…		…
1678		1904
1679	my ($cb, $w, $rcb) = $arg{cb};	1905	my ($cb, $w, $rcb) = $arg{cb};
1680		1906
1681	$rcb = sub {	1907	$rcb = sub {
1682	if ($cb) {	1908	if ($cb) {
1683	$w = _time;	1909	$w = AE::time;
1684	&$cb;	1910	&$cb;
1685	$w = _time - $w;	1911	$w = AE::time - $w;
1686		1912
1687	# never use more then 50% of the time for the idle watcher,	1913	# never use more then 50% of the time for the idle watcher,
1688	# within some limits	1914	# within some limits
1689	$w = 0.0001 if $w < 0.0001;	1915	$w = 0.0001 if $w < 0.0001;
1690	$w = 5 if $w > 5;	1916	$w = 5 if $w > 5;
…		…
1737		1963
1738	sub _send {	1964	sub _send {
1739	# nop	1965	# nop
1740	}	1966	}
1741		1967
		1968	sub _wait {
		1969	AnyEvent->_poll until $_[0]{_ae_sent};
		1970	}
		1971
1742	sub send {	1972	sub send {
1743	my $cv = shift;	1973	my $cv = shift;
1744	$cv->{_ae_sent} = [@_];	1974	$cv->{_ae_sent} = [@_];
1745	(delete $cv->{_ae_cb})->($cv) if $cv->{_ae_cb};	1975	(delete $cv->{_ae_cb})->($cv) if $cv->{_ae_cb};
1746	$cv->_send;	1976	$cv->_send;
…		…
1753		1983
1754	sub ready {	1984	sub ready {
1755	$_[0]{_ae_sent}	1985	$_[0]{_ae_sent}
1756	}	1986	}
1757		1987
1758	sub _wait {
1759	$WAITING
1760	and !$_[0]{_ae_sent}
1761	and Carp::croak "AnyEvent::CondVar: recursive blocking wait detected";
1762
1763	local $WAITING = 1;
1764	AnyEvent->one_event while !$_[0]{_ae_sent};
1765	}
1766
1767	sub recv {	1988	sub recv {
		1989	unless ($_[0]{_ae_sent}) {
		1990	$WAITING
		1991	and Carp::croak "AnyEvent::CondVar: recursive blocking wait attempted";
		1992
		1993	local $WAITING = 1;
1768	$_[0]->_wait;	1994	$_[0]->_wait;
		1995	}
1769		1996
1770	Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak};	1997	$_[0]{_ae_croak}
1771	wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0]	1998	and Carp::croak $_[0]{_ae_croak};
		1999
		2000	wantarray
		2001	? @{ $_[0]{_ae_sent} }
		2002	: $_[0]{_ae_sent}[0]
1772	}	2003	}
1773		2004
1774	sub cb {	2005	sub cb {
1775	my $cv = shift;	2006	my $cv = shift;
1776		2007
…		…
1792	&{ $_[0]{_ae_end_cb} \|\| sub { $_[0]->send } };	2023	&{ $_[0]{_ae_end_cb} \|\| sub { $_[0]->send } };
1793	}	2024	}
1794		2025
1795	# undocumented/compatibility with pre-3.4	2026	# undocumented/compatibility with pre-3.4
1796	*broadcast = \&send;	2027	*broadcast = \&send;
1797	*wait = \&_wait;	2028	*wait = \&recv;
1798		2029
1799	=head1 ERROR AND EXCEPTION HANDLING	2030	=head1 ERROR AND EXCEPTION HANDLING
1800		2031
1801	In general, AnyEvent does not do any error handling - it relies on the	2032	In general, AnyEvent does not do any error handling - it relies on the
1802	caller to do that if required. The L<AnyEvent::Strict> module (see also	2033	caller to do that if required. The L<AnyEvent::Strict> module (see also
…		…
1814	$Event/EV::DIED->() >>, L<Glib> uses C<< install_exception_handler >> and	2045	$Event/EV::DIED->() >>, L<Glib> uses C<< install_exception_handler >> and
1815	so on.	2046	so on.
1816		2047
1817	=head1 ENVIRONMENT VARIABLES	2048	=head1 ENVIRONMENT VARIABLES
1818		2049
1819	The following environment variables are used by this module or its	2050	AnyEvent supports a number of environment variables that tune the
1820	submodules.	2051	runtime behaviour. They are usually evaluated when AnyEvent is
		2052	loaded, initialised, or a submodule that uses them is loaded. Many of
		2053	them also cause AnyEvent to load additional modules - for example,
		2054	C<PERL_ANYEVENT_DEBUG_WRAP> causes the L<AnyEvent::Debug> module to be
		2055	loaded.
1821		2056
1822	Note that AnyEvent will remove I<all> environment variables starting with	2057	All the environment variables documented here start with
1823	C<PERL_ANYEVENT_> from C<%ENV> when it is loaded while taint mode is	2058	C<PERL_ANYEVENT_>, which is what AnyEvent considers its own
1824	enabled.	2059	namespace. Other modules are encouraged (but by no means required) to use
		2060	C<PERL_ANYEVENT_SUBMODULE> if they have registered the AnyEvent::Submodule
		2061	namespace on CPAN, for any submodule. For example, L<AnyEvent::HTTP> could
		2062	be expected to use C<PERL_ANYEVENT_HTTP_PROXY> (it should not access env
		2063	variables starting with C<AE_>, see below).
		2064
		2065	All variables can also be set via the C<AE_> prefix, that is, instead
		2066	of setting C<PERL_ANYEVENT_VERBOSE> you can also set C<AE_VERBOSE>. In
		2067	case there is a clash btween anyevent and another program that uses
		2068	C<AE_something> you can set the corresponding C<PERL_ANYEVENT_something>
		2069	variable to the empty string, as those variables take precedence.
		2070
		2071	When AnyEvent is first loaded, it copies all C<AE_xxx> env variables
		2072	to their C<PERL_ANYEVENT_xxx> counterpart unless that variable already
		2073	exists. If taint mode is on, then AnyEvent will remove I<all> environment
		2074	variables starting with C<PERL_ANYEVENT_> from C<%ENV> (or replace them
		2075	with C<undef> or the empty string, if the corresaponding C<AE_> variable
		2076	is set).
		2077
		2078	The exact algorithm is currently:
		2079
		2080	1. if taint mode enabled, delete all PERL_ANYEVENT_xyz variables from %ENV
		2081	2. copy over AE_xyz to PERL_ANYEVENT_xyz unless the latter alraedy exists
		2082	3. if taint mode enabled, set all PERL_ANYEVENT_xyz variables to undef.
		2083
		2084	This ensures that child processes will not see the C<AE_> variables.
		2085
		2086	The following environment variables are currently known to AnyEvent:
1825		2087
1826	=over 4	2088	=over 4
1827		2089
1828	=item C<PERL_ANYEVENT_VERBOSE>	2090	=item C<PERL_ANYEVENT_VERBOSE>
1829		2091
1830	By default, AnyEvent will be completely silent except in fatal	2092	By default, AnyEvent will log messages with loglevel C<4> (C<error>) or
1831	conditions. You can set this environment variable to make AnyEvent more	2093	higher (see L<AnyEvent::Log>). You can set this environment variable to a
1832	talkative.	2094	numerical loglevel to make AnyEvent more (or less) talkative.
1833		2095
		2096	If you want to do more than just set the global logging level
		2097	you should have a look at C<PERL_ANYEVENT_LOG>, which allows much more
		2098	complex specifications.
		2099
		2100	When set to C<0> (C<off>), then no messages whatsoever will be logged with
		2101	everything else at defaults.
		2102
1834	When set to C<1> or higher, causes AnyEvent to warn about unexpected	2103	When set to C<5> or higher (C<warn>), AnyEvent warns about unexpected
1835	conditions, such as not being able to load the event model specified by	2104	conditions, such as not being able to load the event model specified by
1836	C<PERL_ANYEVENT_MODEL>.	2105	C<PERL_ANYEVENT_MODEL>, or a guard callback throwing an exception - this
		2106	is the minimum recommended level for use during development.
1837		2107
1838	When set to C<2> or higher, cause AnyEvent to report to STDERR which event	2108	When set to C<7> or higher (info), AnyEvent reports which event model it
1839	model it chooses.	2109	chooses.
1840		2110
1841	When set to C<8> or higher, then AnyEvent will report extra information on	2111	When set to C<8> or higher (debug), then AnyEvent will report extra
1842	which optional modules it loads and how it implements certain features.	2112	information on which optional modules it loads and how it implements
		2113	certain features.
		2114
		2115	=item C<PERL_ANYEVENT_LOG>
		2116
		2117	Accepts rather complex logging specifications. For example, you could log
		2118	all C<debug> messages of some module to stderr, warnings and above to
		2119	stderr, and errors and above to syslog, with:
		2120
		2121	PERL_ANYEVENT_LOG=Some::Module=debug,+log:filter=warn,+%syslog:%syslog=error,syslog
		2122
		2123	For the rather extensive details, see L<AnyEvent::Log>.
		2124
		2125	This variable is evaluated when AnyEvent (or L<AnyEvent::Log>) is loaded,
		2126	so will take effect even before AnyEvent has initialised itself.
		2127
		2128	Note that specifying this environment variable causes the L<AnyEvent::Log>
		2129	module to be loaded, while C<PERL_ANYEVENT_VERBOSE> does not, so only
		2130	using the latter saves a few hundred kB of memory unless a module
		2131	explicitly needs the extra features of AnyEvent::Log.
1843		2132
1844	=item C<PERL_ANYEVENT_STRICT>	2133	=item C<PERL_ANYEVENT_STRICT>
1845		2134
1846	AnyEvent does not do much argument checking by default, as thorough	2135	AnyEvent does not do much argument checking by default, as thorough
1847	argument checking is very costly. Setting this variable to a true value	2136	argument checking is very costly. Setting this variable to a true value
…		…
1854	Unlike C<use strict> (or its modern cousin, C<< use L<common::sense>	2143	Unlike C<use strict> (or its modern cousin, C<< use L<common::sense>
1855	>>, it is definitely recommended to keep it off in production. Keeping	2144	>>, it is definitely recommended to keep it off in production. Keeping
1856	C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs	2145	C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs
1857	can be very useful, however.	2146	can be very useful, however.
1858		2147
		2148	=item C<PERL_ANYEVENT_DEBUG_SHELL>
		2149
		2150	If this env variable is nonempty, then its contents will be interpreted by
		2151	C<AnyEvent::Socket::parse_hostport> and C<AnyEvent::Debug::shell> (after
		2152	replacing every occurance of C<$$> by the process pid). The shell object
		2153	is saved in C<$AnyEvent::Debug::SHELL>.
		2154
		2155	This happens when the first watcher is created.
		2156
		2157	For example, to bind a debug shell on a unix domain socket in
		2158	F<< /tmp/debug<pid>.sock >>, you could use this:
		2159
		2160	PERL_ANYEVENT_DEBUG_SHELL=/tmp/debug\$\$.sock perlprog
		2161	# connect with e.g.: socat readline /tmp/debug123.sock
		2162
		2163	Or to bind to tcp port 4545 on localhost:
		2164
		2165	PERL_ANYEVENT_DEBUG_SHELL=127.0.0.1:4545 perlprog
		2166	# connect with e.g.: telnet localhost 4545
		2167
		2168	Note that creating sockets in F</tmp> or on localhost is very unsafe on
		2169	multiuser systems.
		2170
		2171	=item C<PERL_ANYEVENT_DEBUG_WRAP>
		2172
		2173	Can be set to C<0>, C<1> or C<2> and enables wrapping of all watchers for
		2174	debugging purposes. See C<AnyEvent::Debug::wrap> for details.
		2175
1859	=item C<PERL_ANYEVENT_MODEL>	2176	=item C<PERL_ANYEVENT_MODEL>
1860		2177
1861	This can be used to specify the event model to be used by AnyEvent, before	2178	This can be used to specify the event model to be used by AnyEvent, before
1862	auto detection and -probing kicks in. It must be a string consisting	2179	auto detection and -probing kicks in.
1863	entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended	2180
		2181	It normally is a string consisting entirely of ASCII letters (e.g. C<EV>
		2182	or C<IOAsync>). The string C<AnyEvent::Impl::> gets prepended and the
1864	and the resulting module name is loaded and if the load was successful,	2183	resulting module name is loaded and - if the load was successful - used as
1865	used as event model. If it fails to load AnyEvent will proceed with	2184	event model backend. If it fails to load then AnyEvent will proceed with
1866	auto detection and -probing.	2185	auto detection and -probing.
1867		2186
1868	This functionality might change in future versions.	2187	If the string ends with C<::> instead (e.g. C<AnyEvent::Impl::EV::>) then
		2188	nothing gets prepended and the module name is used as-is (hint: C<::> at
		2189	the end of a string designates a module name and quotes it appropriately).
1869		2190
1870	For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you	2191	For example, to force the pure perl model (L<AnyEvent::Loop::Perl>) you
1871	could start your program like this:	2192	could start your program like this:
1872		2193
1873	PERL_ANYEVENT_MODEL=Perl perl ...	2194	PERL_ANYEVENT_MODEL=Perl perl ...
		2195
		2196	=item C<PERL_ANYEVENT_IO_MODEL>
		2197
		2198	The current file I/O model - see L<AnyEvent::IO> for more info.
		2199
		2200	At the moment, only C<Perl> (small, pure-perl, synchronous) and
		2201	C<IOAIO> (truly asynchronous) are supported. The default is C<IOAIO> if
		2202	L<AnyEvent::AIO> can be loaded, otherwise it is C<Perl>.
1874		2203
1875	=item C<PERL_ANYEVENT_PROTOCOLS>	2204	=item C<PERL_ANYEVENT_PROTOCOLS>
1876		2205
1877	Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences	2206	Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences
1878	for IPv4 or IPv6. The default is unspecified (and might change, or be the result	2207	for IPv4 or IPv6. The default is unspecified (and might change, or be the result
…		…
1883	used, and preference will be given to protocols mentioned earlier in the	2212	used, and preference will be given to protocols mentioned earlier in the
1884	list.	2213	list.
1885		2214
1886	This variable can effectively be used for denial-of-service attacks	2215	This variable can effectively be used for denial-of-service attacks
1887	against local programs (e.g. when setuid), although the impact is likely	2216	against local programs (e.g. when setuid), although the impact is likely
1888	small, as the program has to handle conenction and other failures anyways.	2217	small, as the program has to handle connection and other failures anyways.
1889		2218
1890	Examples: C<PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6> - prefer IPv4 over IPv6,	2219	Examples: C<PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6> - prefer IPv4 over IPv6,
1891	but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4>	2220	but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4>
1892	- only support IPv4, never try to resolve or contact IPv6	2221	- only support IPv4, never try to resolve or contact IPv6
1893	addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or	2222	addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or
1894	IPv6, but prefer IPv6 over IPv4.	2223	IPv6, but prefer IPv6 over IPv4.
1895		2224
		2225	=item C<PERL_ANYEVENT_HOSTS>
		2226
		2227	This variable, if specified, overrides the F</etc/hosts> file used by
		2228	L<AnyEvent::Socket>C<::resolve_sockaddr>, i.e. hosts aliases will be read
		2229	from that file instead.
		2230
1896	=item C<PERL_ANYEVENT_EDNS0>	2231	=item C<PERL_ANYEVENT_EDNS0>
1897		2232
1898	Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension	2233	Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension for
1899	for DNS. This extension is generally useful to reduce DNS traffic, but	2234	DNS. This extension is generally useful to reduce DNS traffic, especially
1900	some (broken) firewalls drop such DNS packets, which is why it is off by	2235	when DNSSEC is involved, but some (broken) firewalls drop such DNS
1901	default.	2236	packets, which is why it is off by default.
1902		2237
1903	Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce	2238	Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce
1904	EDNS0 in its DNS requests.	2239	EDNS0 in its DNS requests.
1905		2240
1906	=item C<PERL_ANYEVENT_MAX_FORKS>	2241	=item C<PERL_ANYEVENT_MAX_FORKS>
…		…
1912		2247
1913	The default value for the C<max_outstanding> parameter for the default DNS	2248	The default value for the C<max_outstanding> parameter for the default DNS
1914	resolver - this is the maximum number of parallel DNS requests that are	2249	resolver - this is the maximum number of parallel DNS requests that are
1915	sent to the DNS server.	2250	sent to the DNS server.
1916		2251
		2252	=item C<PERL_ANYEVENT_MAX_SIGNAL_LATENCY>
		2253
		2254	Perl has inherently racy signal handling (you can basically choose between
		2255	losing signals and memory corruption) - pure perl event loops (including
		2256	C<AnyEvent::Loop>, when C<Async::Interrupt> isn't available) therefore
		2257	have to poll regularly to avoid losing signals.
		2258
		2259	Some event loops are racy, but don't poll regularly, and some event loops
		2260	are written in C but are still racy. For those event loops, AnyEvent
		2261	installs a timer that regularly wakes up the event loop.
		2262
		2263	By default, the interval for this timer is C<10> seconds, but you can
		2264	override this delay with this environment variable (or by setting
		2265	the C<$AnyEvent::MAX_SIGNAL_LATENCY> variable before creating signal
		2266	watchers).
		2267
		2268	Lower values increase CPU (and energy) usage, higher values can introduce
		2269	long delays when reaping children or waiting for signals.
		2270
		2271	The L<AnyEvent::Async> module, if available, will be used to avoid this
		2272	polling (with most event loops).
		2273
1917	=item C<PERL_ANYEVENT_RESOLV_CONF>	2274	=item C<PERL_ANYEVENT_RESOLV_CONF>
1918		2275
1919	The file to use instead of F</etc/resolv.conf> (or OS-specific	2276	The absolute path to a F<resolv.conf>-style file to use instead of
1920	configuration) in the default resolver. When set to the empty string, no	2277	F</etc/resolv.conf> (or the OS-specific configuration) in the default
1921	default config will be used.	2278	resolver, or the empty string to select the default configuration.
1922		2279
1923	=item C<PERL_ANYEVENT_CA_FILE>, C<PERL_ANYEVENT_CA_PATH>.	2280	=item C<PERL_ANYEVENT_CA_FILE>, C<PERL_ANYEVENT_CA_PATH>.
1924		2281
1925	When neither C<ca_file> nor C<ca_path> was specified during	2282	When neither C<ca_file> nor C<ca_path> was specified during
1926	L<AnyEvent::TLS> context creation, and either of these environment	2283	L<AnyEvent::TLS> context creation, and either of these environment
1927	variables exist, they will be used to specify CA certificate locations	2284	variables are nonempty, they will be used to specify CA certificate
1928	instead of a system-dependent default.	2285	locations instead of a system-dependent default.
1929		2286
1930	=item C<PERL_ANYEVENT_AVOID_GUARD> and C<PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT>	2287	=item C<PERL_ANYEVENT_AVOID_GUARD> and C<PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT>
1931		2288
1932	When these are set to C<1>, then the respective modules are not	2289	When these are set to C<1>, then the respective modules are not
1933	loaded. Mostly good for testing AnyEvent itself.	2290	loaded. Mostly good for testing AnyEvent itself.
…		…
2265	(even when used without AnyEvent), but most event loops have acceptable	2622	(even when used without AnyEvent), but most event loops have acceptable
2266	performance with or without AnyEvent.	2623	performance with or without AnyEvent.
2267		2624
2268	=item * The overhead AnyEvent adds is usually much smaller than the overhead of	2625	=item * The overhead AnyEvent adds is usually much smaller than the overhead of
2269	the actual event loop, only with extremely fast event loops such as EV	2626	the actual event loop, only with extremely fast event loops such as EV
2270	adds AnyEvent significant overhead.	2627	does AnyEvent add significant overhead.
2271		2628
2272	=item * You should avoid POE like the plague if you want performance or	2629	=item * You should avoid POE like the plague if you want performance or
2273	reasonable memory usage.	2630	reasonable memory usage.
2274		2631
2275	=back	2632	=back
…		…
2574		2931
2575	=item L<Time::HiRes>	2932	=item L<Time::HiRes>
2576		2933
2577	This module is part of perl since release 5.008. It will be used when the	2934	This module is part of perl since release 5.008. It will be used when the
2578	chosen event library does not come with a timing source of its own. The	2935	chosen event library does not come with a timing source of its own. The
2579	pure-perl event loop (L<AnyEvent::Impl::Perl>) will additionally use it to	2936	pure-perl event loop (L<AnyEvent::Loop>) will additionally load it to
2580	try to use a monotonic clock for timing stability.	2937	try to use a monotonic clock for timing stability.
		2938
		2939	=item L<AnyEvent::AIO> (and L<IO::AIO>)
		2940
		2941	The default implementation of L<AnyEvent::IO> is to do I/O synchronously,
		2942	stopping programs while they access the disk, which is fine for a lot of
		2943	programs.
		2944
		2945	Installing AnyEvent::AIO (and its IO::AIO dependency) makes it switch to
		2946	a true asynchronous implementation, so event processing can continue even
		2947	while waiting for disk I/O.
2581		2948
2582	=back	2949	=back
2583		2950
2584		2951
2585	=head1 FORK	2952	=head1 FORK
…		…
2597	usually happens when the first AnyEvent watcher is created, or the library	2964	usually happens when the first AnyEvent watcher is created, or the library
2598	is loaded).	2965	is loaded).
2599		2966
2600	If you have to fork, you must either do so I<before> creating your first	2967	If you have to fork, you must either do so I<before> creating your first
2601	watcher OR you must not use AnyEvent at all in the child OR you must do	2968	watcher OR you must not use AnyEvent at all in the child OR you must do
2602	something completely out of the scope of AnyEvent.	2969	something completely out of the scope of AnyEvent (see below).
2603		2970
2604	The problem of doing event processing in the parent I<and> the child	2971	The problem of doing event processing in the parent I<and> the child
2605	is much more complicated: even for backends that I<are> fork-aware or	2972	is much more complicated: even for backends that I<are> fork-aware or
2606	fork-safe, their behaviour is not usually what you want: fork clones all	2973	fork-safe, their behaviour is not usually what you want: fork clones all
2607	watchers, that means all timers, I/O watchers etc. are active in both	2974	watchers, that means all timers, I/O watchers etc. are active in both
2608	parent and child, which is almost never what you want. USing C<exec>	2975	parent and child, which is almost never what you want. Using C<exec>
2609	to start worker children from some kind of manage rprocess is usually	2976	to start worker children from some kind of manage prrocess is usually
2610	preferred, because it is much easier and cleaner, at the expense of having	2977	preferred, because it is much easier and cleaner, at the expense of having
2611	to have another binary.	2978	to have another binary.
		2979
		2980	In addition to logical problems with fork, there are also implementation
		2981	problems. For example, on POSIX systems, you cannot fork at all in Perl
		2982	code if a thread (I am talking of pthreads here) was ever created in the
		2983	process, and this is just the tip of the iceberg. In general, using fork
		2984	from Perl is difficult, and attempting to use fork without an exec to
		2985	implement some kind of parallel processing is almost certainly doomed.
		2986
		2987	To safely fork and exec, you should use a module such as
		2988	L<Proc::FastSpawn> that let's you safely fork and exec new processes.
		2989
		2990	If you want to do multiprocessing using processes, you can
		2991	look at the L<AnyEvent::Fork> module (and some related modules
		2992	such as L<AnyEvent::Fork::RPC>, L<AnyEvent::Fork::Pool> and
		2993	L<AnyEvent::Fork::Remote>). This module allows you to safely create
		2994	subprocesses without any limitations - you can use X11 toolkits or
		2995	AnyEvent in the children created by L<AnyEvent::Fork> safely and without
		2996	any special precautions.
2612		2997
2613		2998
2614	=head1 SECURITY CONSIDERATIONS	2999	=head1 SECURITY CONSIDERATIONS
2615		3000
2616	AnyEvent can be forced to load any event model via	3001	AnyEvent can be forced to load any event model via
…		…
2650		3035
2651	Tutorial/Introduction: L<AnyEvent::Intro>.	3036	Tutorial/Introduction: L<AnyEvent::Intro>.
2652		3037
2653	FAQ: L<AnyEvent::FAQ>.	3038	FAQ: L<AnyEvent::FAQ>.
2654		3039
2655	Utility functions: L<AnyEvent::Util>.	3040	Utility functions: L<AnyEvent::Util> (misc. grab-bag), L<AnyEvent::Log>
		3041	(simply logging).
2656		3042
2657	Event modules: L<EV>, L<EV::Glib>, L<Glib::EV>, L<Event>, L<Glib::Event>,	3043	Development/Debugging: L<AnyEvent::Strict> (stricter checking),
2658	L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.	3044	L<AnyEvent::Debug> (interactive shell, watcher tracing).
		3045
		3046	Supported event modules: L<AnyEvent::Loop>, L<EV>, L<EV::Glib>,
		3047	L<Glib::EV>, L<Event>, L<Glib::Event>, L<Glib>, L<Tk>, L<Event::Lib>,
		3048	L<Qt>, L<POE>, L<FLTK>.
2659		3049
2660	Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,	3050	Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,
2661	L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,	3051	L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,
2662	L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,	3052	L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,
2663	L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>.	3053	L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>,
		3054	L<AnyEvent::Impl::FLTK>.
2664		3055
2665	Non-blocking file handles, sockets, TCP clients and	3056	Non-blocking handles, pipes, stream sockets, TCP clients and
2666	servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.	3057	servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.
		3058
		3059	Asynchronous File I/O: L<AnyEvent::IO>.
2667		3060
2668	Asynchronous DNS: L<AnyEvent::DNS>.	3061	Asynchronous DNS: L<AnyEvent::DNS>.
2669		3062
2670	Thread support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>.	3063	Thread support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>.
2671		3064
…		…
2674		3067
2675		3068
2676	=head1 AUTHOR	3069	=head1 AUTHOR
2677		3070
2678	Marc Lehmann <schmorp@schmorp.de>	3071	Marc Lehmann <schmorp@schmorp.de>
2679	http://home.schmorp.de/	3072	http://anyevent.schmorp.de
2680		3073
2681	=cut	3074	=cut
2682		3075
2683	1	3076	1
2684		3077

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Comparing AnyEvent/lib/AnyEvent.pm (file contents): Revision 1.345 by root, Fri Dec 31 04:50:44 2010 UTC vs. Revision 1.419 by root, Thu Aug 28 15:26:20 2014 UTC

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Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.345 by root, Fri Dec 31 04:50:44 2010 UTC vs.
Revision 1.419 by root, Thu Aug 28 15:26:20 2014 UTC