[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 1.417 by root, Tue Dec 17 18:36:22 2013 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, Perl, Event::Lib, Irssi, rxvt-unicode, IO::Async, Qt,
6	and POE are various supported event loops/environments.	6	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
…		…
878	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.	888	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
879	AnyEvent::Impl::POE based on POE, very slow, some limitations.	889	AnyEvent::Impl::POE based on POE, very slow, some limitations.
880	AnyEvent::Impl::Irssi used when running within irssi.	890	AnyEvent::Impl::Irssi used when running within irssi.
881	AnyEvent::Impl::IOAsync based on IO::Async.	891	AnyEvent::Impl::IOAsync based on IO::Async.
882	AnyEvent::Impl::Cocoa based on Cocoa::EventLoop.	892	AnyEvent::Impl::Cocoa based on Cocoa::EventLoop.
		893	AnyEvent::Impl::FLTK based on FLTK (fltk 2 binding).
883		894
884	=item Backends with special needs.	895	=item Backends with special needs.
885		896
886	Qt requires the Qt::Application to be instantiated first, but will	897	Qt requires the Qt::Application to be instantiated first, but will
887	otherwise be picked up automatically. As long as the main program	898	otherwise be picked up automatically. As long as the main program
…		…
932		943
933	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model	944	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model
934	if necessary. You should only call this function right before you would	945	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	946	have created an AnyEvent watcher anyway, that is, as late as possible at
936	runtime, and not e.g. during initialisation of your module.	947	runtime, and not e.g. during initialisation of your module.
		948
		949	The effect of calling this function is as if a watcher had been created
		950	(specifically, actions that happen "when the first watcher is created"
		951	happen when calling detetc as well).
937		952
938	If you need to do some initialisation before AnyEvent watchers are	953	If you need to do some initialisation before AnyEvent watchers are
939	created, use C<post_detect>.	954	created, use C<post_detect>.
940		955
941	=item $guard = AnyEvent::post_detect { BLOCK }	956	=item $guard = AnyEvent::post_detect { BLOCK }
…		…
1004	# AnyEvent not yet initialised, so make sure to load Coro::AnyEvent	1019	# AnyEvent not yet initialised, so make sure to load Coro::AnyEvent
1005	# as soon as it is	1020	# as soon as it is
1006	push @AnyEvent::post_detect, sub { require Coro::AnyEvent };	1021	push @AnyEvent::post_detect, sub { require Coro::AnyEvent };
1007	}	1022	}
1008		1023
		1024	=item AnyEvent::postpone { BLOCK }
		1025
		1026	Arranges for the block to be executed as soon as possible, but not before
		1027	the call itself returns. In practise, the block will be executed just
		1028	before the event loop polls for new events, or shortly afterwards.
		1029
		1030	This function never returns anything (to make the C<return postpone { ...
		1031	}> idiom more useful.
		1032
		1033	To understand the usefulness of this function, consider a function that
		1034	asynchronously does something for you and returns some transaction
		1035	object or guard to let you cancel the operation. For example,
		1036	C<AnyEvent::Socket::tcp_connect>:
		1037
		1038	# start a conenction attempt unless one is active
		1039	$self->{connect_guard} \|\|= AnyEvent::Socket::tcp_connect "www.example.net", 80, sub {
		1040	delete $self->{connect_guard};
		1041	...
		1042	};
		1043
		1044	Imagine that this function could instantly call the callback, for
		1045	example, because it detects an obvious error such as a negative port
		1046	number. Invoking the callback before the function returns causes problems
		1047	however: the callback will be called and will try to delete the guard
		1048	object. But since the function hasn't returned yet, there is nothing to
		1049	delete. When the function eventually returns it will assign the guard
		1050	object to C<< $self->{connect_guard} >>, where it will likely never be
		1051	deleted, so the program thinks it is still trying to connect.
		1052
		1053	This is where C<AnyEvent::postpone> should be used. Instead of calling the
		1054	callback directly on error:
		1055
		1056	$cb->(undef), return # signal error to callback, BAD!
		1057	if $some_error_condition;
		1058
		1059	It should use C<postpone>:
		1060
		1061	AnyEvent::postpone { $cb->(undef) }, return # signal error to callback, later
		1062	if $some_error_condition;
		1063
		1064	=item AnyEvent::log $level, $msg[, @args]
		1065
		1066	Log the given C<$msg> at the given C<$level>.
		1067
		1068	If L<AnyEvent::Log> is not loaded then this function makes a simple test
		1069	to see whether the message will be logged. If the test succeeds it will
		1070	load AnyEvent::Log and call C<AnyEvent::Log::log> - consequently, look at
		1071	the L<AnyEvent::Log> documentation for details.
		1072
		1073	If the test fails it will simply return. Right now this happens when a
		1074	numerical loglevel is used and it is larger than the level specified via
		1075	C<$ENV{PERL_ANYEVENT_VERBOSE}>.
		1076
		1077	If you want to sprinkle loads of logging calls around your code, consider
		1078	creating a logger callback with the C<AnyEvent::Log::logger> function,
		1079	which can reduce typing, codesize and can reduce the logging overhead
		1080	enourmously.
		1081
1009	=back	1082	=back
1010		1083
1011	=head1 WHAT TO DO IN A MODULE	1084	=head1 WHAT TO DO IN A MODULE
1012		1085
1013	As a module author, you should C<use AnyEvent> and call AnyEvent methods	1086	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	1119	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	1120	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.	1121	might choose the wrong one unless you load the correct one yourself.
1049		1122
1050	You can chose to use a pure-perl implementation by loading the	1123	You can chose to use a pure-perl implementation by loading the
1051	C<AnyEvent::Impl::Perl> module, which gives you similar behaviour	1124	C<AnyEvent::Loop> module, which gives you similar behaviour
1052	everywhere, but letting AnyEvent chose the model is generally better.	1125	everywhere, but letting AnyEvent chose the model is generally better.
1053		1126
1054	=head2 MAINLOOP EMULATION	1127	=head2 MAINLOOP EMULATION
1055		1128
1056	Sometimes (often for short test scripts, or even standalone programs who	1129	Sometimes (often for short test scripts, or even standalone programs who
…		…
1069		1142
1070		1143
1071	=head1 OTHER MODULES	1144	=head1 OTHER MODULES
1072		1145
1073	The following is a non-exhaustive list of additional modules that use	1146	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	1147	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	1148	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.	1149	modules come as part of AnyEvent, the others are available via CPAN (see
		1150	L<http://search.cpan.org/search?m=module&q=anyevent%3A%3A*> for
		1151	a longer non-exhaustive list), and the list is heavily biased towards
		1152	modules of the AnyEvent author himself :)
1077		1153
1078	=over 4	1154	=over 4
1079		1155
1080	=item L<AnyEvent::Util>	1156	=item L<AnyEvent::Util> (part of the AnyEvent distribution)
1081		1157
1082	Contains various utility functions that replace often-used blocking	1158	Contains various utility functions that replace often-used blocking
1083	functions such as C<inet_aton> with event/callback-based versions.	1159	functions such as C<inet_aton> with event/callback-based versions.
1084		1160
1085	=item L<AnyEvent::Socket>	1161	=item L<AnyEvent::Socket> (part of the AnyEvent distribution)
1086		1162
1087	Provides various utility functions for (internet protocol) sockets,	1163	Provides various utility functions for (internet protocol) sockets,
1088	addresses and name resolution. Also functions to create non-blocking tcp	1164	addresses and name resolution. Also functions to create non-blocking tcp
1089	connections or tcp servers, with IPv6 and SRV record support and more.	1165	connections or tcp servers, with IPv6 and SRV record support and more.
1090		1166
1091	=item L<AnyEvent::Handle>	1167	=item L<AnyEvent::Handle> (part of the AnyEvent distribution)
1092		1168
1093	Provide read and write buffers, manages watchers for reads and writes,	1169	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	1170	supports raw and formatted I/O, I/O queued and fully transparent and
1095	non-blocking SSL/TLS (via L<AnyEvent::TLS>).	1171	non-blocking SSL/TLS (via L<AnyEvent::TLS>).
1096		1172
1097	=item L<AnyEvent::DNS>	1173	=item L<AnyEvent::DNS> (part of the AnyEvent distribution)
1098		1174
1099	Provides rich asynchronous DNS resolver capabilities.	1175	Provides rich asynchronous DNS resolver capabilities.
1100		1176
1101	=item L<AnyEvent::HTTP>, L<AnyEvent::IRC>, L<AnyEvent::XMPP>, L<AnyEvent::GPSD>, L<AnyEvent::IGS>, L<AnyEvent::FCP>	1177	=item L<AnyEvent::HTTP>, L<AnyEvent::IRC>, L<AnyEvent::XMPP>, L<AnyEvent::GPSD>, L<AnyEvent::IGS>, L<AnyEvent::FCP>
1102		1178
1103	Implement event-based interfaces to the protocols of the same name (for	1179	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	1180	the curious, IGS is the International Go Server and FCP is the Freenet
1105	Client Protocol).	1181	Client Protocol).
1106		1182
1107	=item L<AnyEvent::Handle::UDP>	1183	=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		1184
1131	Truly asynchronous (as opposed to non-blocking) I/O, should be in the	1185	Truly asynchronous (as opposed to non-blocking) I/O, should be in the
1132	toolbox of every event programmer. AnyEvent::AIO transparently fuses	1186	toolbox of every event programmer. AnyEvent::AIO transparently fuses
1133	L<IO::AIO> and AnyEvent together, giving AnyEvent access to event-based	1187	L<IO::AIO> and AnyEvent together, giving AnyEvent access to event-based
1134	file I/O, and much more.	1188	file I/O, and much more.
1135		1189
		1190	=item L<AnyEvent::Fork>, L<AnyEvent::Fork::RPC>, L<AnyEvent::Fork::Pool>, L<AnyEvent::Fork::Remote>
		1191
		1192	These let you safely fork new subprocesses, either locally or
		1193	remotely (e.g.v ia ssh), using some RPC protocol or not, without
		1194	the limitations normally imposed by fork (AnyEvent works fine for
		1195	example). Dynamically-resized worker pools are obviously included as well.
		1196
		1197	And they are quite tiny and fast as well - "abusing" L<AnyEvent::Fork>
		1198	just to exec external programs can easily beat using C<fork> and C<exec>
		1199	(or even C<system>) in most programs.
		1200
		1201	=item L<AnyEvent::Filesys::Notify>
		1202
		1203	AnyEvent is good for non-blocking stuff, but it can't detect file or
		1204	path changes (e.g. "watch this directory for new files", "watch this
		1205	file for changes"). The L<AnyEvent::Filesys::Notify> module promises to
		1206	do just that in a portbale fashion, supporting inotify on GNU/Linux and
		1207	some weird, without doubt broken, stuff on OS X to monitor files. It can
		1208	fall back to blocking scans at regular intervals transparently on other
		1209	platforms, so it's about as portable as it gets.
		1210
		1211	(I haven't used it myself, but it seems the biggest problem with it is
		1212	it quite bad performance).
		1213
1136	=item L<AnyEvent::HTTPD>	1214	=item L<AnyEvent::DBI>
1137		1215
1138	A simple embedded webserver.	1216	Executes L<DBI> requests asynchronously in a proxy process for you,
		1217	notifying you in an event-based way when the operation is finished.
1139		1218
1140	=item L<AnyEvent::FastPing>	1219	=item L<AnyEvent::FastPing>
1141		1220
1142	The fastest ping in the west.	1221	The fastest ping in the west.
1143		1222
1144	=item L<Coro>	1223	=item L<Coro>
1145		1224
1146	Has special support for AnyEvent via L<Coro::AnyEvent>.	1225	Has special support for AnyEvent via L<Coro::AnyEvent>, which allows you
		1226	to simply invert the flow control - don't call us, we will call you:
		1227
		1228	async {
		1229	Coro::AnyEvent::sleep 5; # creates a 5s timer and waits for it
		1230	print "5 seconds later!\n";
		1231
		1232	Coro::AnyEvent::readable *STDIN; # uses an I/O watcher
		1233	my $line = <STDIN>; # works for ttys
		1234
		1235	AnyEvent::HTTP::http_get "url", Coro::rouse_cb;
		1236	my ($body, $hdr) = Coro::rouse_wait;
		1237	};
1147		1238
1148	=back	1239	=back
1149		1240
1150	=cut	1241	=cut
1151		1242
1152	package AnyEvent;	1243	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		1244
1176	BEGIN {	1245	BEGIN {
1177	require "AnyEvent/constants.pl";	1246	require "AnyEvent/constants.pl";
		1247	&AnyEvent::common_sense;
		1248	}
1178		1249
		1250	use Carp ();
		1251
		1252	our $VERSION = '7.07';
		1253	our $MODEL;
		1254	our @ISA;
		1255	our @REGISTRY;
		1256	our $VERBOSE;
		1257	our %PROTOCOL; # (ipv4\|ipv6) => (1\|2), higher numbers are preferred
		1258	our $MAX_SIGNAL_LATENCY = $ENV{PERL_ANYEVENT_MAX_SIGNAL_LATENCY} \|\| 10; # executes after the BEGIN block below (tainting!)
		1259
		1260	BEGIN {
1179	eval "sub TAINT (){" . (${^TAINT}*1) . "}";	1261	eval "sub TAINT (){" . (${^TAINT}*1) . "}";
1180		1262
1181	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}	1263	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}
1182	if ${^TAINT};	1264	if ${^TAINT};
1183		1265
1184	$VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1;	1266	$ENV{"PERL_ANYEVENT_$_"} = $ENV{"AE_$_"}
		1267	for grep s/^AE_// && !exists $ENV{"PERL_ANYEVENT_$_"}, keys %ENV;
1185		1268
1186	}	1269	@ENV{grep /^PERL_ANYEVENT_/, keys %ENV} = ()
		1270	if ${^TAINT};
1187		1271
1188	our $MAX_SIGNAL_LATENCY = 10;	1272	# $ENV{PERL_ANYEVENT_xxx} now valid
1189		1273
1190	our %PROTOCOL; # (ipv4\|ipv6) => (1\|2), higher numbers are preferred	1274	$VERBOSE = length $ENV{PERL_ANYEVENT_VERBOSE} ? $ENV{PERL_ANYEVENT_VERBOSE}*1 : 4;
1191		1275
1192	{
1193	my $idx;	1276	my $idx;
1194	$PROTOCOL{$_} = ++$idx	1277	$PROTOCOL{$_} = ++$idx
1195	for reverse split /\s,\s/,	1278	for reverse split /\s,\s/,
1196	$ENV{PERL_ANYEVENT_PROTOCOLS} \|\| "ipv4,ipv6";	1279	$ENV{PERL_ANYEVENT_PROTOCOLS} \|\| "ipv4,ipv6";
1197	}	1280	}
1198		1281
		1282	our @post_detect;
		1283
		1284	sub post_detect(&) {
		1285	my ($cb) = @_;
		1286
		1287	push @post_detect, $cb;
		1288
		1289	defined wantarray
		1290	? bless \$cb, "AnyEvent::Util::postdetect"
		1291	: ()
		1292	}
		1293
		1294	sub AnyEvent::Util::postdetect::DESTROY {
		1295	@post_detect = grep $_ != ${$_[0]}, @post_detect;
		1296	}
		1297
		1298	our $POSTPONE_W;
		1299	our @POSTPONE;
		1300
		1301	sub _postpone_exec {
		1302	undef $POSTPONE_W;
		1303
		1304	&{ shift @POSTPONE }
		1305	while @POSTPONE;
		1306	}
		1307
		1308	sub postpone(&) {
		1309	push @POSTPONE, shift;
		1310
		1311	$POSTPONE_W \|\|= AE::timer (0, 0, \&_postpone_exec);
		1312
		1313	()
		1314	}
		1315
		1316	sub log($$;@) {
		1317	# only load the big bloated module when we actually are about to log something
		1318	if ($_[0] <= ($VERBOSE \|\| 1)) { # also catches non-numeric levels(!) and fatal
		1319	local ($!, $@);
		1320	require AnyEvent::Log; # among other things, sets $VERBOSE to 9
		1321	# AnyEvent::Log overwrites this function
		1322	goto &log;
		1323	}
		1324
		1325	0 # not logged
		1326	}
		1327
		1328	sub _logger($;$) {
		1329	my ($level, $renabled) = @_;
		1330
		1331	$$renabled = $level <= $VERBOSE;
		1332
		1333	my $logger = [(caller)[0], $level, $renabled];
		1334
		1335	$AnyEvent::Log::LOGGER{$logger+0} = $logger;
		1336
		1337	# return unless defined wantarray;
		1338	#
		1339	# require AnyEvent::Util;
		1340	# my $guard = AnyEvent::Util::guard (sub {
		1341	# # "clean up"
		1342	# delete $LOGGER{$logger+0};
		1343	# });
		1344	#
		1345	# sub {
		1346	# return 0 unless $$renabled;
		1347	#
		1348	# $guard if 0; # keep guard alive, but don't cause runtime overhead
		1349	# require AnyEvent::Log unless $AnyEvent::Log::VERSION;
		1350	# package AnyEvent::Log;
		1351	# _log ($logger->[0], $level, @_) # logger->[0] has been converted at load time
		1352	# }
		1353	}
		1354
		1355	if (length $ENV{PERL_ANYEVENT_LOG}) {
		1356	require AnyEvent::Log; # AnyEvent::Log does the thing for us
		1357	}
		1358
1199	my @models = (	1359	our @models = (
1200	[EV:: => AnyEvent::Impl::EV:: , 1],	1360	[EV:: => AnyEvent::Impl::EV::],
1201	[AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl:: , 1],	1361	[AnyEvent::Loop:: => AnyEvent::Impl::Perl::],
1202	# everything below here will not (normally) be autoprobed	1362	# everything below here will not (normally) be autoprobed
1203	# as the pureperl backend should work everywhere	1363	# as the pure perl backend should work everywhere
1204	# and is usually faster	1364	# and is usually faster
		1365	[Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package, so msut be near the top
1205	[Event:: => AnyEvent::Impl::Event::, 1],	1366	[Event:: => AnyEvent::Impl::Event::], # slow, stable
1206	[Glib:: => AnyEvent::Impl::Glib:: , 1], # becomes extremely slow with many watchers	1367	[Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers
		1368	# everything below here should not be autoloaded
1207	[Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy	1369	[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	1370	[Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
1210	[Qt:: => AnyEvent::Impl::Qt::], # requires special main program	1371	[Qt:: => AnyEvent::Impl::Qt::], # requires special main program
1211	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza	1372	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
1212	[Wx:: => AnyEvent::Impl::POE::],	1373	[Wx:: => AnyEvent::Impl::POE::],
1213	[Prima:: => AnyEvent::Impl::POE::],	1374	[Prima:: => AnyEvent::Impl::POE::],
1214	[IO::Async::Loop:: => AnyEvent::Impl::IOAsync::],	1375	[IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # a bitch to autodetect
1215	[Cocoa::EventLoop:: => AnyEvent::Impl::Cocoa::],	1376	[Cocoa::EventLoop:: => AnyEvent::Impl::Cocoa::],
		1377	[FLTK:: => AnyEvent::Impl::FLTK::],
1216	);	1378	);
1217		1379
1218	our %method = map +($_ => 1),	1380	our @isa_hook;
		1381
		1382	sub _isa_set {
		1383	my @pkg = ("AnyEvent", (map $_->[0], grep defined, @isa_hook), $MODEL);
		1384
		1385	@{"$pkg[$_-1]::ISA"} = $pkg[$_]
		1386	for 1 .. $#pkg;
		1387
		1388	grep $_ && $_->[1], @isa_hook
		1389	and AE::_reset ();
		1390	}
		1391
		1392	# used for hooking AnyEvent::Strict and AnyEvent::Debug::Wrap into the class hierarchy
		1393	sub _isa_hook($$;$) {
		1394	my ($i, $pkg, $reset_ae) = @_;
		1395
		1396	$isa_hook[$i] = $pkg ? [$pkg, $reset_ae] : undef;
		1397
		1398	_isa_set;
		1399	}
		1400
		1401	# all autoloaded methods reserve the complete glob, not just the method slot.
		1402	# due to bugs in perls method cache implementation.
1219	qw(io timer time now now_update signal child idle condvar one_event DESTROY);	1403	our @methods = qw(io timer time now now_update signal child idle condvar);
1220
1221	our @post_detect;
1222
1223	sub post_detect(&) {
1224	my ($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		1404
1237	sub detect() {	1405	sub detect() {
		1406	return $MODEL if $MODEL; # some programs keep references to detect
		1407
		1408	# IO::Async::Loop::AnyEvent is extremely evil, refuse to work with it
		1409	# the author knows about the problems and what it does to AnyEvent as a whole
		1410	# (and the ability of others to use AnyEvent), but simply wants to abuse AnyEvent
		1411	# anyway.
		1412	AnyEvent::log fatal => "IO::Async::Loop::AnyEvent detected - that module is broken by\n"
		1413	. "design, abuses internals and breaks AnyEvent - will not continue."
		1414	if exists $INC{"IO/Async/Loop/AnyEvent.pm"};
		1415
		1416	local $!; # for good measure
		1417	local $SIG{__DIE__}; # we use eval
		1418
1238	# free some memory	1419	# free some memory
1239	*detect = sub () { $MODEL };	1420	*detect = sub () { $MODEL };
		1421	# undef &func doesn't correctly update the method cache. grmbl.
		1422	# so we delete the whole glob. grmbl.
		1423	# otoh, perl doesn't let me undef an active usb, but it lets me free
		1424	# a glob with an active sub. hrm. i hope it works, but perl is
		1425	# usually buggy in this department. sigh.
		1426	delete @{"AnyEvent::"}{@methods};
		1427	undef @methods;
1240		1428
1241	local $!; # for good measure
1242	local $SIG{__DIE__};
1243
1244	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {	1429	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z0-9:]+)$/) {
1245	my $model = "AnyEvent::Impl::$1";	1430	my $model = $1;
		1431	$model = "AnyEvent::Impl::$model" unless $model =~ s/::$//;
1246	if (eval "require $model") {	1432	if (eval "require $model") {
		1433	AnyEvent::log 7 => "Loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.";
1247	$MODEL = $model;	1434	$MODEL = $model;
1248	warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2;
1249	} else {	1435	} else {
1250	warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE;	1436	AnyEvent::log 4 => "Unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@";
1251	}	1437	}
1252	}	1438	}
1253		1439
1254	# check for already loaded models	1440	# check for already loaded models
1255	unless ($MODEL) {	1441	unless ($MODEL) {
1256	for (@REGISTRY, @models) {	1442	for (@REGISTRY, @models) {
1257	my ($package, $model) = @$_;	1443	my ($package, $model) = @$_;
1258	if (${"$package\::VERSION"} > 0) {	1444	if (${"$package\::VERSION"} > 0) {
1259	if (eval "require $model") {	1445	if (eval "require $model") {
		1446	AnyEvent::log 7 => "Autodetected model '$model', using it.";
1260	$MODEL = $model;	1447	$MODEL = $model;
1261	warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2;	1448	last;
		1449	} else {
		1450	AnyEvent::log 8 => "Detected event loop $package, but cannot load '$model', skipping: $@";
		1451	}
		1452	}
		1453	}
		1454
		1455	unless ($MODEL) {
		1456	# try to autoload a model
		1457	for (@REGISTRY, @models) {
		1458	my ($package, $model) = @$_;
		1459	if (
		1460	eval "require $package"
		1461	and ${"$package\::VERSION"} > 0
		1462	and eval "require $model"
		1463	) {
		1464	AnyEvent::log 7 => "Autoloaded model '$model', using it.";
		1465	$MODEL = $model;
1262	last;	1466	last;
1263	}	1467	}
1264	}	1468	}
1265	}
1266
1267	unless ($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		1469
1283	$MODEL	1470	$MODEL
1284	or die "AnyEvent: backend autodetection failed - did you properly install AnyEvent?\n";	1471	or AnyEvent::log fatal => "Backend autodetection failed - did you properly install AnyEvent?";
1285	}	1472	}
1286	}	1473	}
1287		1474
1288	@models = (); # free probe data	1475	# free memory only needed for probing
		1476	undef @models;
		1477	undef @REGISTRY;
1289		1478
1290	push @{"$MODEL\::ISA"}, "AnyEvent::Base";	1479	push @{"$MODEL\::ISA"}, "AnyEvent::Base";
1291	unshift @ISA, $MODEL;
1292		1480
1293	# now nuke some methods that are overridden by the backend.	1481	# now nuke some methods that are overridden by the backend.
1294	# SUPER is not allowed.	1482	# SUPER usage is not allowed in these.
1295	for (qw(time signal child idle)) {	1483	for (qw(time signal child idle)) {
1296	undef &{"AnyEvent::Base::$_"}	1484	undef &{"AnyEvent::Base::$_"}
1297	if defined &{"$MODEL\::$_"};	1485	if defined &{"$MODEL\::$_"};
1298	}	1486	}
1299		1487
		1488	_isa_set;
		1489
		1490	# we're officially open!
		1491
1300	if ($ENV{PERL_ANYEVENT_STRICT}) {	1492	if ($ENV{PERL_ANYEVENT_STRICT}) {
1301	eval { require AnyEvent::Strict };	1493	require AnyEvent::Strict;
1302	warn "AnyEvent: cannot load AnyEvent::Strict: $@"
1303	if $@ && $VERBOSE;
1304	}	1494	}
1305		1495
		1496	if ($ENV{PERL_ANYEVENT_DEBUG_WRAP}) {
		1497	require AnyEvent::Debug;
		1498	AnyEvent::Debug::wrap ($ENV{PERL_ANYEVENT_DEBUG_WRAP});
		1499	}
		1500
		1501	if (length $ENV{PERL_ANYEVENT_DEBUG_SHELL}) {
		1502	require AnyEvent::Socket;
		1503	require AnyEvent::Debug;
		1504
		1505	my $shell = $ENV{PERL_ANYEVENT_DEBUG_SHELL};
		1506	$shell =~ s/\$\$/$$/g;
		1507
		1508	my ($host, $service) = AnyEvent::Socket::parse_hostport ($shell);
		1509	$AnyEvent::Debug::SHELL = AnyEvent::Debug::shell ($host, $service);
		1510	}
		1511
		1512	# now the anyevent environment is set up as the user told us to, so
		1513	# call the actual user code - post detects
		1514
1306	(shift @post_detect)->() while @post_detect;	1515	(shift @post_detect)->() while @post_detect;
		1516	undef @post_detect;
1307		1517
1308	*post_detect = sub(&) {	1518	*post_detect = sub(&) {
1309	shift->();	1519	shift->();
1310		1520
1311	undef	1521	undef
1312	};	1522	};
1313		1523
1314	$MODEL	1524	$MODEL
1315	}	1525	}
1316		1526
1317	sub AUTOLOAD {	1527	for my $name (@methods) {
1318	(my $func = $AUTOLOAD) =~ s/.*://;	1528	*$name = sub {
1319
1320	$method{$func}
1321	or Carp::croak "$func: not a valid AnyEvent class method";
1322
1323	detect;	1529	detect;
1324		1530	# we use goto because
1325	my $class = shift;	1531	# a) it makes the thunk more transparent
1326	$class->$func (@_);	1532	# b) it allows us to delete the thunk later
		1533	goto &{ UNIVERSAL::can AnyEvent => "SUPER::$name" }
		1534	};
1327	}	1535	}
1328		1536
1329	# utility function to dup a filehandle. this is used by many backends	1537	# utility function to dup a filehandle. this is used by many backends
1330	# to support binding more than one watcher per filehandle (they usually	1538	# 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).	1539	# allow only one watcher per fd, so we dup it to get a different one).
…		…
1355		1563
1356	package AE;	1564	package AE;
1357		1565
1358	our $VERSION = $AnyEvent::VERSION;	1566	our $VERSION = $AnyEvent::VERSION;
1359		1567
		1568	sub _reset() {
		1569	eval q{
1360	# fall back to the main API by default - backends and AnyEvent::Base	1570	# fall back to the main API by default - backends and AnyEvent::Base
1361	# implementations can overwrite these.	1571	# implementations can overwrite these.
1362		1572
1363	sub io($$$) {	1573	sub io($$$) {
1364	AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])	1574	AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])
1365	}	1575	}
1366		1576
1367	sub timer($$$) {	1577	sub timer($$$) {
1368	AnyEvent->timer (after => $_[0], interval => $_[1], cb => $_[2])	1578	AnyEvent->timer (after => $_[0], interval => $_[1], cb => $_[2])
1369	}	1579	}
1370		1580
1371	sub signal($$) {	1581	sub signal($$) {
1372	AnyEvent->signal (signal => $_[0], cb => $_[1])	1582	AnyEvent->signal (signal => $_[0], cb => $_[1])
1373	}	1583	}
1374		1584
1375	sub child($$) {	1585	sub child($$) {
1376	AnyEvent->child (pid => $_[0], cb => $_[1])	1586	AnyEvent->child (pid => $_[0], cb => $_[1])
1377	}	1587	}
1378		1588
1379	sub idle($) {	1589	sub idle($) {
1380	AnyEvent->idle (cb => $_[0])	1590	AnyEvent->idle (cb => $_[0]);
1381	}	1591	}
1382		1592
1383	sub cv(;&) {	1593	sub cv(;&) {
1384	AnyEvent->condvar (@_ ? (cb => $_[0]) : ())	1594	AnyEvent->condvar (@_ ? (cb => $_[0]) : ())
1385	}	1595	}
1386		1596
1387	sub now() {	1597	sub now() {
1388	AnyEvent->now	1598	AnyEvent->now
1389	}	1599	}
1390		1600
1391	sub now_update() {	1601	sub now_update() {
1392	AnyEvent->now_update	1602	AnyEvent->now_update
1393	}	1603	}
1394		1604
1395	sub time() {	1605	sub time() {
1396	AnyEvent->time	1606	AnyEvent->time
		1607	}
		1608
		1609	*postpone = \&AnyEvent::postpone;
		1610	*log = \&AnyEvent::log;
		1611	};
		1612	die if $@;
1397	}	1613	}
		1614
		1615	BEGIN { _reset }
1398		1616
1399	package AnyEvent::Base;	1617	package AnyEvent::Base;
1400		1618
1401	# default implementations for many methods	1619	# default implementations for many methods
1402		1620
1403	sub time {	1621	sub time {
1404	eval q{ # poor man's autoloading {}	1622	eval q{ # poor man's autoloading {}
1405	# probe for availability of Time::HiRes	1623	# probe for availability of Time::HiRes
1406	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {	1624	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
1407	warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8;	1625	*time = sub { Time::HiRes::time () };
1408	*AE::time = \&Time::HiRes::time;	1626	*AE::time = \& Time::HiRes::time ;
		1627	*now = \&time;
		1628	AnyEvent::log 8 => "using Time::HiRes for sub-second timing accuracy.";
1409	# if (eval "use POSIX (); (POSIX::times())...	1629	# if (eval "use POSIX (); (POSIX::times())...
1410	} else {	1630	} else {
1411	warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE;	1631	*time = sub { CORE::time };
1412	*AE::time = sub (){ time }; # epic fail	1632	*AE::time = sub (){ CORE::time };
		1633	*now = \&time;
		1634	AnyEvent::log 3 => "Using built-in time(), no sub-second resolution!";
1413	}	1635	}
1414
1415	*time = sub { AE::time }; # different prototypes
1416	};	1636	};
1417	die if $@;	1637	die if $@;
1418		1638
1419	&time	1639	&time
1420	}	1640	}
1421		1641
1422	*now = \&time;	1642	*now = \&time;
1423
1424	sub now_update { }	1643	sub now_update { }
1425		1644
		1645	sub _poll {
		1646	Carp::croak "$AnyEvent::MODEL does not support blocking waits. Caught";
		1647	}
		1648
1426	# default implementation for ->condvar	1649	# default implementation for ->condvar
		1650	# in fact, the default should not be overwritten
1427		1651
1428	sub condvar {	1652	sub condvar {
1429	eval q{ # poor man's autoloading {}	1653	eval q{ # poor man's autoloading {}
1430	*condvar = sub {	1654	*condvar = sub {
1431	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"	1655	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"
…		…
1509		1733
1510	sub signal {	1734	sub signal {
1511	eval q{ # poor man's autoloading {}	1735	eval q{ # poor man's autoloading {}
1512	# probe for availability of Async::Interrupt	1736	# probe for availability of Async::Interrupt
1513	if (_have_async_interrupt) {	1737	if (_have_async_interrupt) {
1514	warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8;	1738	AnyEvent::log 8 => "Using Async::Interrupt for race-free signal handling.";
1515		1739
1516	$SIGPIPE_R = new Async::Interrupt::EventPipe;	1740	$SIGPIPE_R = new Async::Interrupt::EventPipe;
1517	$SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;	1741	$SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;
1518		1742
1519	} else {	1743	} else {
1520	warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;	1744	AnyEvent::log 8 => "Using emulated perl signal handling with latency timer.";
1521		1745
1522	if (AnyEvent::WIN32) {	1746	if (AnyEvent::WIN32) {
1523	require AnyEvent::Util;	1747	require AnyEvent::Util;
1524		1748
1525	($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();	1749	($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
…		…
1601	: sysread $SIGPIPE_R, (my $dummy), 9;	1825	: sysread $SIGPIPE_R, (my $dummy), 9;
1602		1826
1603	while (%SIG_EV) {	1827	while (%SIG_EV) {
1604	for (keys %SIG_EV) {	1828	for (keys %SIG_EV) {
1605	delete $SIG_EV{$_};	1829	delete $SIG_EV{$_};
1606	$_->() for values %{ $SIG_CB{$_} \|\| {} };	1830	&$_ for values %{ $SIG_CB{$_} \|\| {} };
1607	}	1831	}
1608	}	1832	}
1609	};	1833	};
1610	};	1834	};
1611	die if $@;	1835	die if $@;
…		…
1638	};	1862	};
1639		1863
1640	*child = sub {	1864	*child = sub {
1641	my (undef, %arg) = @_;	1865	my (undef, %arg) = @_;
1642		1866
1643	defined (my $pid = $arg{pid} + 0)	1867	my $pid = $arg{pid};
1644	or Carp::croak "required option 'pid' is missing";	1868	my $cb = $arg{cb};
1645		1869
1646	$PID_CB{$pid}{$arg{cb}} = $arg{cb};	1870	$PID_CB{$pid}{$cb+0} = $cb;
1647		1871
1648	unless ($CHLD_W) {	1872	unless ($CHLD_W) {
1649	$CHLD_W = AE::signal CHLD => \&_sigchld;	1873	$CHLD_W = AE::signal CHLD => \&_sigchld;
1650	# child could be a zombie already, so make at least one round	1874	# child could be a zombie already, so make at least one round
1651	&_sigchld;	1875	&_sigchld;
1652	}	1876	}
1653		1877
1654	bless [$pid, $arg{cb}], "AnyEvent::Base::child"	1878	bless [$pid, $cb+0], "AnyEvent::Base::child"
1655	};	1879	};
1656		1880
1657	*AnyEvent::Base::child::DESTROY = sub {	1881	*AnyEvent::Base::child::DESTROY = sub {
1658	my ($pid, $cb) = @{$_[0]};	1882	my ($pid, $icb) = @{$_[0]};
1659		1883
1660	delete $PID_CB{$pid}{$cb};	1884	delete $PID_CB{$pid}{$icb};
1661	delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };	1885	delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} };
1662		1886
1663	undef $CHLD_W unless keys %PID_CB;	1887	undef $CHLD_W unless keys %PID_CB;
1664	};	1888	};
1665	};	1889	};
…		…
1678		1902
1679	my ($cb, $w, $rcb) = $arg{cb};	1903	my ($cb, $w, $rcb) = $arg{cb};
1680		1904
1681	$rcb = sub {	1905	$rcb = sub {
1682	if ($cb) {	1906	if ($cb) {
1683	$w = _time;	1907	$w = AE::time;
1684	&$cb;	1908	&$cb;
1685	$w = _time - $w;	1909	$w = AE::time - $w;
1686		1910
1687	# never use more then 50% of the time for the idle watcher,	1911	# never use more then 50% of the time for the idle watcher,
1688	# within some limits	1912	# within some limits
1689	$w = 0.0001 if $w < 0.0001;	1913	$w = 0.0001 if $w < 0.0001;
1690	$w = 5 if $w > 5;	1914	$w = 5 if $w > 5;
…		…
1737		1961
1738	sub _send {	1962	sub _send {
1739	# nop	1963	# nop
1740	}	1964	}
1741		1965
		1966	sub _wait {
		1967	AnyEvent->_poll until $_[0]{_ae_sent};
		1968	}
		1969
1742	sub send {	1970	sub send {
1743	my $cv = shift;	1971	my $cv = shift;
1744	$cv->{_ae_sent} = [@_];	1972	$cv->{_ae_sent} = [@_];
1745	(delete $cv->{_ae_cb})->($cv) if $cv->{_ae_cb};	1973	(delete $cv->{_ae_cb})->($cv) if $cv->{_ae_cb};
1746	$cv->_send;	1974	$cv->_send;
…		…
1753		1981
1754	sub ready {	1982	sub ready {
1755	$_[0]{_ae_sent}	1983	$_[0]{_ae_sent}
1756	}	1984	}
1757		1985
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 {	1986	sub recv {
		1987	unless ($_[0]{_ae_sent}) {
		1988	$WAITING
		1989	and Carp::croak "AnyEvent::CondVar: recursive blocking wait attempted";
		1990
		1991	local $WAITING = 1;
1768	$_[0]->_wait;	1992	$_[0]->_wait;
		1993	}
1769		1994
1770	Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak};	1995	$_[0]{_ae_croak}
1771	wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0]	1996	and Carp::croak $_[0]{_ae_croak};
		1997
		1998	wantarray
		1999	? @{ $_[0]{_ae_sent} }
		2000	: $_[0]{_ae_sent}[0]
1772	}	2001	}
1773		2002
1774	sub cb {	2003	sub cb {
1775	my $cv = shift;	2004	my $cv = shift;
1776		2005
…		…
1792	&{ $_[0]{_ae_end_cb} \|\| sub { $_[0]->send } };	2021	&{ $_[0]{_ae_end_cb} \|\| sub { $_[0]->send } };
1793	}	2022	}
1794		2023
1795	# undocumented/compatibility with pre-3.4	2024	# undocumented/compatibility with pre-3.4
1796	*broadcast = \&send;	2025	*broadcast = \&send;
1797	*wait = \&_wait;	2026	*wait = \&recv;
1798		2027
1799	=head1 ERROR AND EXCEPTION HANDLING	2028	=head1 ERROR AND EXCEPTION HANDLING
1800		2029
1801	In general, AnyEvent does not do any error handling - it relies on the	2030	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	2031	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	2043	$Event/EV::DIED->() >>, L<Glib> uses C<< install_exception_handler >> and
1815	so on.	2044	so on.
1816		2045
1817	=head1 ENVIRONMENT VARIABLES	2046	=head1 ENVIRONMENT VARIABLES
1818		2047
1819	The following environment variables are used by this module or its	2048	AnyEvent supports a number of environment variables that tune the
1820	submodules.	2049	runtime behaviour. They are usually evaluated when AnyEvent is
		2050	loaded, initialised, or a submodule that uses them is loaded. Many of
		2051	them also cause AnyEvent to load additional modules - for example,
		2052	C<PERL_ANYEVENT_DEBUG_WRAP> causes the L<AnyEvent::Debug> module to be
		2053	loaded.
1821		2054
1822	Note that AnyEvent will remove I<all> environment variables starting with	2055	All the environment variables documented here start with
1823	C<PERL_ANYEVENT_> from C<%ENV> when it is loaded while taint mode is	2056	C<PERL_ANYEVENT_>, which is what AnyEvent considers its own
1824	enabled.	2057	namespace. Other modules are encouraged (but by no means required) to use
		2058	C<PERL_ANYEVENT_SUBMODULE> if they have registered the AnyEvent::Submodule
		2059	namespace on CPAN, for any submodule. For example, L<AnyEvent::HTTP> could
		2060	be expected to use C<PERL_ANYEVENT_HTTP_PROXY> (it should not access env
		2061	variables starting with C<AE_>, see below).
		2062
		2063	All variables can also be set via the C<AE_> prefix, that is, instead
		2064	of setting C<PERL_ANYEVENT_VERBOSE> you can also set C<AE_VERBOSE>. In
		2065	case there is a clash btween anyevent and another program that uses
		2066	C<AE_something> you can set the corresponding C<PERL_ANYEVENT_something>
		2067	variable to the empty string, as those variables take precedence.
		2068
		2069	When AnyEvent is first loaded, it copies all C<AE_xxx> env variables
		2070	to their C<PERL_ANYEVENT_xxx> counterpart unless that variable already
		2071	exists. If taint mode is on, then AnyEvent will remove I<all> environment
		2072	variables starting with C<PERL_ANYEVENT_> from C<%ENV> (or replace them
		2073	with C<undef> or the empty string, if the corresaponding C<AE_> variable
		2074	is set).
		2075
		2076	The exact algorithm is currently:
		2077
		2078	1. if taint mode enabled, delete all PERL_ANYEVENT_xyz variables from %ENV
		2079	2. copy over AE_xyz to PERL_ANYEVENT_xyz unless the latter alraedy exists
		2080	3. if taint mode enabled, set all PERL_ANYEVENT_xyz variables to undef.
		2081
		2082	This ensures that child processes will not see the C<AE_> variables.
		2083
		2084	The following environment variables are currently known to AnyEvent:
1825		2085
1826	=over 4	2086	=over 4
1827		2087
1828	=item C<PERL_ANYEVENT_VERBOSE>	2088	=item C<PERL_ANYEVENT_VERBOSE>
1829		2089
1830	By default, AnyEvent will be completely silent except in fatal	2090	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	2091	higher (see L<AnyEvent::Log>). You can set this environment variable to a
1832	talkative.	2092	numerical loglevel to make AnyEvent more (or less) talkative.
1833		2093
		2094	If you want to do more than just set the global logging level
		2095	you should have a look at C<PERL_ANYEVENT_LOG>, which allows much more
		2096	complex specifications.
		2097
		2098	When set to C<0> (C<off>), then no messages whatsoever will be logged with
		2099	everything else at defaults.
		2100
1834	When set to C<1> or higher, causes AnyEvent to warn about unexpected	2101	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	2102	conditions, such as not being able to load the event model specified by
1836	C<PERL_ANYEVENT_MODEL>.	2103	C<PERL_ANYEVENT_MODEL>, or a guard callback throwing an exception - this
		2104	is the minimum recommended level for use during development.
1837		2105
1838	When set to C<2> or higher, cause AnyEvent to report to STDERR which event	2106	When set to C<7> or higher (info), AnyEvent reports which event model it
1839	model it chooses.	2107	chooses.
1840		2108
1841	When set to C<8> or higher, then AnyEvent will report extra information on	2109	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.	2110	information on which optional modules it loads and how it implements
		2111	certain features.
		2112
		2113	=item C<PERL_ANYEVENT_LOG>
		2114
		2115	Accepts rather complex logging specifications. For example, you could log
		2116	all C<debug> messages of some module to stderr, warnings and above to
		2117	stderr, and errors and above to syslog, with:
		2118
		2119	PERL_ANYEVENT_LOG=Some::Module=debug,+log:filter=warn,+%syslog:%syslog=error,syslog
		2120
		2121	For the rather extensive details, see L<AnyEvent::Log>.
		2122
		2123	This variable is evaluated when AnyEvent (or L<AnyEvent::Log>) is loaded,
		2124	so will take effect even before AnyEvent has initialised itself.
		2125
		2126	Note that specifying this environment variable causes the L<AnyEvent::Log>
		2127	module to be loaded, while C<PERL_ANYEVENT_VERBOSE> does not, so only
		2128	using the latter saves a few hundred kB of memory unless a module
		2129	explicitly needs the extra features of AnyEvent::Log.
1843		2130
1844	=item C<PERL_ANYEVENT_STRICT>	2131	=item C<PERL_ANYEVENT_STRICT>
1845		2132
1846	AnyEvent does not do much argument checking by default, as thorough	2133	AnyEvent does not do much argument checking by default, as thorough
1847	argument checking is very costly. Setting this variable to a true value	2134	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>	2141	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	2142	>>, it is definitely recommended to keep it off in production. Keeping
1856	C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs	2143	C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs
1857	can be very useful, however.	2144	can be very useful, however.
1858		2145
		2146	=item C<PERL_ANYEVENT_DEBUG_SHELL>
		2147
		2148	If this env variable is nonempty, then its contents will be interpreted by
		2149	C<AnyEvent::Socket::parse_hostport> and C<AnyEvent::Debug::shell> (after
		2150	replacing every occurance of C<$$> by the process pid). The shell object
		2151	is saved in C<$AnyEvent::Debug::SHELL>.
		2152
		2153	This happens when the first watcher is created.
		2154
		2155	For example, to bind a debug shell on a unix domain socket in
		2156	F<< /tmp/debug<pid>.sock >>, you could use this:
		2157
		2158	PERL_ANYEVENT_DEBUG_SHELL=/tmp/debug\$\$.sock perlprog
		2159	# connect with e.g.: socat readline /tmp/debug123.sock
		2160
		2161	Or to bind to tcp port 4545 on localhost:
		2162
		2163	PERL_ANYEVENT_DEBUG_SHELL=127.0.0.1:4545 perlprog
		2164	# connect with e.g.: telnet localhost 4545
		2165
		2166	Note that creating sockets in F</tmp> or on localhost is very unsafe on
		2167	multiuser systems.
		2168
		2169	=item C<PERL_ANYEVENT_DEBUG_WRAP>
		2170
		2171	Can be set to C<0>, C<1> or C<2> and enables wrapping of all watchers for
		2172	debugging purposes. See C<AnyEvent::Debug::wrap> for details.
		2173
1859	=item C<PERL_ANYEVENT_MODEL>	2174	=item C<PERL_ANYEVENT_MODEL>
1860		2175
1861	This can be used to specify the event model to be used by AnyEvent, before	2176	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	2177	auto detection and -probing kicks in.
1863	entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended	2178
		2179	It normally is a string consisting entirely of ASCII letters (e.g. C<EV>
		2180	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,	2181	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	2182	event model backend. If it fails to load then AnyEvent will proceed with
1866	auto detection and -probing.	2183	auto detection and -probing.
1867		2184
1868	This functionality might change in future versions.	2185	If the string ends with C<::> instead (e.g. C<AnyEvent::Impl::EV::>) then
		2186	nothing gets prepended and the module name is used as-is (hint: C<::> at
		2187	the end of a string designates a module name and quotes it appropriately).
1869		2188
1870	For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you	2189	For example, to force the pure perl model (L<AnyEvent::Loop::Perl>) you
1871	could start your program like this:	2190	could start your program like this:
1872		2191
1873	PERL_ANYEVENT_MODEL=Perl perl ...	2192	PERL_ANYEVENT_MODEL=Perl perl ...
		2193
		2194	=item C<PERL_ANYEVENT_IO_MODEL>
		2195
		2196	The current file I/O model - see L<AnyEvent::IO> for more info.
		2197
		2198	At the moment, only C<Perl> (small, pure-perl, synchronous) and
		2199	C<IOAIO> (truly asynchronous) are supported. The default is C<IOAIO> if
		2200	L<AnyEvent::AIO> can be loaded, otherwise it is C<Perl>.
1874		2201
1875	=item C<PERL_ANYEVENT_PROTOCOLS>	2202	=item C<PERL_ANYEVENT_PROTOCOLS>
1876		2203
1877	Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences	2204	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	2205	for IPv4 or IPv6. The default is unspecified (and might change, or be the result
…		…
1891	but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4>	2218	but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4>
1892	- only support IPv4, never try to resolve or contact IPv6	2219	- only support IPv4, never try to resolve or contact IPv6
1893	addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or	2220	addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or
1894	IPv6, but prefer IPv6 over IPv4.	2221	IPv6, but prefer IPv6 over IPv4.
1895		2222
		2223	=item C<PERL_ANYEVENT_HOSTS>
		2224
		2225	This variable, if specified, overrides the F</etc/hosts> file used by
		2226	L<AnyEvent::Socket>C<::resolve_sockaddr>, i.e. hosts aliases will be read
		2227	from that file instead.
		2228
1896	=item C<PERL_ANYEVENT_EDNS0>	2229	=item C<PERL_ANYEVENT_EDNS0>
1897		2230
1898	Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension	2231	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	2232	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	2233	when DNSSEC is involved, but some (broken) firewalls drop such DNS
1901	default.	2234	packets, which is why it is off by default.
1902		2235
1903	Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce	2236	Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce
1904	EDNS0 in its DNS requests.	2237	EDNS0 in its DNS requests.
1905		2238
1906	=item C<PERL_ANYEVENT_MAX_FORKS>	2239	=item C<PERL_ANYEVENT_MAX_FORKS>
…		…
1912		2245
1913	The default value for the C<max_outstanding> parameter for the default DNS	2246	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	2247	resolver - this is the maximum number of parallel DNS requests that are
1915	sent to the DNS server.	2248	sent to the DNS server.
1916		2249
		2250	=item C<PERL_ANYEVENT_MAX_SIGNAL_LATENCY>
		2251
		2252	Perl has inherently racy signal handling (you can basically choose between
		2253	losing signals and memory corruption) - pure perl event loops (including
		2254	C<AnyEvent::Loop>, when C<Async::Interrupt> isn't available) therefore
		2255	have to poll regularly to avoid losing signals.
		2256
		2257	Some event loops are racy, but don't poll regularly, and some event loops
		2258	are written in C but are still racy. For those event loops, AnyEvent
		2259	installs a timer that regularly wakes up the event loop.
		2260
		2261	By default, the interval for this timer is C<10> seconds, but you can
		2262	override this delay with this environment variable (or by setting
		2263	the C<$AnyEvent::MAX_SIGNAL_LATENCY> variable before creating signal
		2264	watchers).
		2265
		2266	Lower values increase CPU (and energy) usage, higher values can introduce
		2267	long delays when reaping children or waiting for signals.
		2268
		2269	The L<AnyEvent::Async> module, if available, will be used to avoid this
		2270	polling (with most event loops).
		2271
1917	=item C<PERL_ANYEVENT_RESOLV_CONF>	2272	=item C<PERL_ANYEVENT_RESOLV_CONF>
1918		2273
1919	The file to use instead of F</etc/resolv.conf> (or OS-specific	2274	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	2275	F</etc/resolv.conf> (or the OS-specific configuration) in the default
1921	default config will be used.	2276	resolver, or the empty string to select the default configuration.
1922		2277
1923	=item C<PERL_ANYEVENT_CA_FILE>, C<PERL_ANYEVENT_CA_PATH>.	2278	=item C<PERL_ANYEVENT_CA_FILE>, C<PERL_ANYEVENT_CA_PATH>.
1924		2279
1925	When neither C<ca_file> nor C<ca_path> was specified during	2280	When neither C<ca_file> nor C<ca_path> was specified during
1926	L<AnyEvent::TLS> context creation, and either of these environment	2281	L<AnyEvent::TLS> context creation, and either of these environment
1927	variables exist, they will be used to specify CA certificate locations	2282	variables are nonempty, they will be used to specify CA certificate
1928	instead of a system-dependent default.	2283	locations instead of a system-dependent default.
1929		2284
1930	=item C<PERL_ANYEVENT_AVOID_GUARD> and C<PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT>	2285	=item C<PERL_ANYEVENT_AVOID_GUARD> and C<PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT>
1931		2286
1932	When these are set to C<1>, then the respective modules are not	2287	When these are set to C<1>, then the respective modules are not
1933	loaded. Mostly good for testing AnyEvent itself.	2288	loaded. Mostly good for testing AnyEvent itself.
…		…
2265	(even when used without AnyEvent), but most event loops have acceptable	2620	(even when used without AnyEvent), but most event loops have acceptable
2266	performance with or without AnyEvent.	2621	performance with or without AnyEvent.
2267		2622
2268	=item * The overhead AnyEvent adds is usually much smaller than the overhead of	2623	=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	2624	the actual event loop, only with extremely fast event loops such as EV
2270	adds AnyEvent significant overhead.	2625	does AnyEvent add significant overhead.
2271		2626
2272	=item * You should avoid POE like the plague if you want performance or	2627	=item * You should avoid POE like the plague if you want performance or
2273	reasonable memory usage.	2628	reasonable memory usage.
2274		2629
2275	=back	2630	=back
…		…
2574		2929
2575	=item L<Time::HiRes>	2930	=item L<Time::HiRes>
2576		2931
2577	This module is part of perl since release 5.008. It will be used when the	2932	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	2933	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	2934	pure-perl event loop (L<AnyEvent::Loop>) will additionally load it to
2580	try to use a monotonic clock for timing stability.	2935	try to use a monotonic clock for timing stability.
		2936
		2937	=item L<AnyEvent::AIO> (and L<IO::AIO>)
		2938
		2939	The default implementation of L<AnyEvent::IO> is to do I/O synchronously,
		2940	stopping programs while they access the disk, which is fine for a lot of
		2941	programs.
		2942
		2943	Installing AnyEvent::AIO (and its IO::AIO dependency) makes it switch to
		2944	a true asynchronous implementation, so event processing can continue even
		2945	while waiting for disk I/O.
2581		2946
2582	=back	2947	=back
2583		2948
2584		2949
2585	=head1 FORK	2950	=head1 FORK
…		…
2597	usually happens when the first AnyEvent watcher is created, or the library	2962	usually happens when the first AnyEvent watcher is created, or the library
2598	is loaded).	2963	is loaded).
2599		2964
2600	If you have to fork, you must either do so I<before> creating your first	2965	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	2966	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.	2967	something completely out of the scope of AnyEvent (see below).
2603		2968
2604	The problem of doing event processing in the parent I<and> the child	2969	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	2970	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	2971	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	2972	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>	2973	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	2974	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	2975	preferred, because it is much easier and cleaner, at the expense of having
2611	to have another binary.	2976	to have another binary.
		2977
		2978	In addition to logical problems with fork, there are also implementation
		2979	problems. For example, on POSIX systems, you cannot fork at all in Perl
		2980	code if a thread (I am talking of pthreads here) was ever created in the
		2981	process, and this is just the tip of the iceberg. In general, using fork
		2982	from Perl is difficult, and attempting to use fork without an exec to
		2983	implement some kind of parallel processing is almost certainly doomed.
		2984
		2985	To safely fork and exec, you should use a module such as
		2986	L<Proc::FastSpawn> that let's you safely fork and exec new processes.
		2987
		2988	If you want to do multiprocessing using processes, you can
		2989	look at the L<AnyEvent::Fork> module (and some related modules
		2990	such as L<AnyEvent::Fork::RPC>, L<AnyEvent::Fork::Pool> and
		2991	L<AnyEvent::Fork::Remote>). This module allows you to safely create
		2992	subprocesses without any limitations - you can use X11 toolkits or
		2993	AnyEvent in the children created by L<AnyEvent::Fork> safely and without
		2994	any special precautions.
2612		2995
2613		2996
2614	=head1 SECURITY CONSIDERATIONS	2997	=head1 SECURITY CONSIDERATIONS
2615		2998
2616	AnyEvent can be forced to load any event model via	2999	AnyEvent can be forced to load any event model via
…		…
2650		3033
2651	Tutorial/Introduction: L<AnyEvent::Intro>.	3034	Tutorial/Introduction: L<AnyEvent::Intro>.
2652		3035
2653	FAQ: L<AnyEvent::FAQ>.	3036	FAQ: L<AnyEvent::FAQ>.
2654		3037
2655	Utility functions: L<AnyEvent::Util>.	3038	Utility functions: L<AnyEvent::Util> (misc. grab-bag), L<AnyEvent::Log>
		3039	(simply logging).
2656		3040
2657	Event modules: L<EV>, L<EV::Glib>, L<Glib::EV>, L<Event>, L<Glib::Event>,	3041	Development/Debugging: L<AnyEvent::Strict> (stricter checking),
2658	L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.	3042	L<AnyEvent::Debug> (interactive shell, watcher tracing).
		3043
		3044	Supported event modules: L<AnyEvent::Loop>, L<EV>, L<EV::Glib>,
		3045	L<Glib::EV>, L<Event>, L<Glib::Event>, L<Glib>, L<Tk>, L<Event::Lib>,
		3046	L<Qt>, L<POE>, L<FLTK>.
2659		3047
2660	Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,	3048	Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,
2661	L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,	3049	L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,
2662	L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,	3050	L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,
2663	L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>.	3051	L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>, L<Anyevent::Impl::Irssi>,
		3052	L<AnyEvent::Impl::FLTK>.
2664		3053
2665	Non-blocking file handles, sockets, TCP clients and	3054	Non-blocking handles, pipes, stream sockets, TCP clients and
2666	servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.	3055	servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.
		3056
		3057	Asynchronous File I/O: L<AnyEvent::IO>.
2667		3058
2668	Asynchronous DNS: L<AnyEvent::DNS>.	3059	Asynchronous DNS: L<AnyEvent::DNS>.
2669		3060
2670	Thread support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>.	3061	Thread support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>.
2671		3062
…		…
2674		3065
2675		3066
2676	=head1 AUTHOR	3067	=head1 AUTHOR
2677		3068
2678	Marc Lehmann <schmorp@schmorp.de>	3069	Marc Lehmann <schmorp@schmorp.de>
2679	http://home.schmorp.de/	3070	http://anyevent.schmorp.de
2680		3071
2681	=cut	3072	=cut
2682		3073
2683	1	3074	1
2684		3075

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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 1.417 by root, Tue Dec 17 18:36:22 2013 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 1.417 by root, Tue Dec 17 18:36:22 2013 UTC