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

Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.224 by root, Fri Jul 3 21:44:14 2009 UTC vs.
Revision 1.247 by root, Sat Jul 18 22:24:17 2009 UTC

…		…
176	=head2 I/O WATCHERS	176	=head2 I/O WATCHERS
177		177
178	You can create an I/O watcher by calling the C<< AnyEvent->io >> method	178	You can create an I/O watcher by calling the C<< AnyEvent->io >> method
179	with the following mandatory key-value pairs as arguments:	179	with the following mandatory key-value pairs as arguments:
180		180
181	C<fh> is the Perl I<file handle> (I<not> file descriptor) to watch	181	C<fh> is the Perl I<file handle> (or a naked file descriptor) to watch
182	for events (AnyEvent might or might not keep a reference to this file	182	for events (AnyEvent might or might not keep a reference to this file
183	handle). Note that only file handles pointing to things for which	183	handle). Note that only file handles pointing to things for which
184	non-blocking operation makes sense are allowed. This includes sockets,	184	non-blocking operation makes sense are allowed. This includes sockets,
185	most character devices, pipes, fifos and so on, but not for example files	185	most character devices, pipes, fifos and so on, but not for example files
186	or block devices.	186	or block devices.
…		…
361	invocation, and callback invocation will be synchronous. Synchronous means	361	invocation, and callback invocation will be synchronous. Synchronous means
362	that it might take a while until the signal gets handled by the process,	362	that it might take a while until the signal gets handled by the process,
363	but it is guaranteed not to interrupt any other callbacks.	363	but it is guaranteed not to interrupt any other callbacks.
364		364
365	The main advantage of using these watchers is that you can share a signal	365	The main advantage of using these watchers is that you can share a signal
366	between multiple watchers.	366	between multiple watchers, and AnyEvent will ensure that signals will not
		367	interrupt your program at bad times.
367		368
368	This watcher might use C<%SIG>, so programs overwriting those signals	369	This watcher might use C<%SIG> (depending on the event loop used),
369	directly will likely not work correctly.	370	so programs overwriting those signals directly will likely not work
		371	correctly.
370		372
371	Example: exit on SIGINT	373	Example: exit on SIGINT
372		374
373	my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });	375	my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
		376
		377	=head3 Signal Races, Delays and Workarounds
		378
		379	Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching
		380	callbacks to signals in a generic way, which is a pity, as you cannot do
		381	race-free signal handling in perl. AnyEvent will try to do it's best, but
		382	in some cases, signals will be delayed. The maximum time a signal might
		383	be delayed is specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10
		384	seconds). This variable can be changed only before the first signal
		385	watcher is created, and should be left alone otherwise. Higher values
		386	will cause fewer spurious wake-ups, which is better for power and CPU
		387	saving. All these problems can be avoided by installing the optional
		388	L<Async::Interrupt> module. This will not work with inherently broken
		389	event loops such as L<Event> or L<Event::Lib> (and not with L<POE>
		390	currently, as POE does it's own workaround with one-second latency). With
		391	those, you just have to suffer the delays.
374		392
375	=head2 CHILD PROCESS WATCHERS	393	=head2 CHILD PROCESS WATCHERS
376		394
377	You can also watch on a child process exit and catch its exit status.	395	You can also watch on a child process exit and catch its exit status.
378		396
…		…
403		421
404	This means you cannot create a child watcher as the very first	422	This means you cannot create a child watcher as the very first
405	thing in an AnyEvent program, you I<have> to create at least one	423	thing in an AnyEvent program, you I<have> to create at least one
406	watcher before you C<fork> the child (alternatively, you can call	424	watcher before you C<fork> the child (alternatively, you can call
407	C<AnyEvent::detect>).	425	C<AnyEvent::detect>).
		426
		427	As most event loops do not support waiting for child events, they will be
		428	emulated by AnyEvent in most cases, in which the latency and race problems
		429	mentioned in the description of signal watchers apply.
408		430
409	Example: fork a process and wait for it	431	Example: fork a process and wait for it
410		432
411	my $done = AnyEvent->condvar;	433	my $done = AnyEvent->condvar;
412		434
…		…
463		485
464	If you are familiar with some event loops you will know that all of them	486	If you are familiar with some event loops you will know that all of them
465	require you to run some blocking "loop", "run" or similar function that	487	require you to run some blocking "loop", "run" or similar function that
466	will actively watch for new events and call your callbacks.	488	will actively watch for new events and call your callbacks.
467		489
468	AnyEvent is different, it expects somebody else to run the event loop and	490	AnyEvent is slightly different: it expects somebody else to run the event
469	will only block when necessary (usually when told by the user).	491	loop and will only block when necessary (usually when told by the user).
470		492
471	The instrument to do that is called a "condition variable", so called	493	The instrument to do that is called a "condition variable", so called
472	because they represent a condition that must become true.	494	because they represent a condition that must become true.
473		495
		496	Now is probably a good time to look at the examples further below.
		497
474	Condition variables can be created by calling the C<< AnyEvent->condvar	498	Condition variables can be created by calling the C<< AnyEvent->condvar
475	>> method, usually without arguments. The only argument pair allowed is	499	>> method, usually without arguments. The only argument pair allowed is
476
477	C<cb>, which specifies a callback to be called when the condition variable	500	C<cb>, which specifies a callback to be called when the condition variable
478	becomes true, with the condition variable as the first argument (but not	501	becomes true, with the condition variable as the first argument (but not
479	the results).	502	the results).
480		503
481	After creation, the condition variable is "false" until it becomes "true"	504	After creation, the condition variable is "false" until it becomes "true"
…		…
530	after => 1,	553	after => 1,
531	cb => sub { $result_ready->send },	554	cb => sub { $result_ready->send },
532	);	555	);
533		556
534	# this "blocks" (while handling events) till the callback	557	# this "blocks" (while handling events) till the callback
535	# calls send	558	# calls -<send
536	$result_ready->recv;	559	$result_ready->recv;
537		560
538	Example: wait for a timer, but take advantage of the fact that	561	Example: wait for a timer, but take advantage of the fact that condition
539	condition variables are also code references.	562	variables are also callable directly.
540		563
541	my $done = AnyEvent->condvar;	564	my $done = AnyEvent->condvar;
542	my $delay = AnyEvent->timer (after => 5, cb => $done);	565	my $delay = AnyEvent->timer (after => 5, cb => $done);
543	$done->recv;	566	$done->recv;
544		567
…		…
550		573
551	...	574	...
552		575
553	my @info = $couchdb->info->recv;	576	my @info = $couchdb->info->recv;
554		577
555	And this is how you would just ste a callback to be called whenever the	578	And this is how you would just set a callback to be called whenever the
556	results are available:	579	results are available:
557		580
558	$couchdb->info->cb (sub {	581	$couchdb->info->cb (sub {
559	my @info = $_[0]->recv;	582	my @info = $_[0]->recv;
560	});	583	});
…		…
578	immediately from within send.	601	immediately from within send.
579		602
580	Any arguments passed to the C<send> call will be returned by all	603	Any arguments passed to the C<send> call will be returned by all
581	future C<< ->recv >> calls.	604	future C<< ->recv >> calls.
582		605
583	Condition variables are overloaded so one can call them directly	606	Condition variables are overloaded so one can call them directly (as if
584	(as a code reference). Calling them directly is the same as calling	607	they were a code reference). Calling them directly is the same as calling
585	C<send>. Note, however, that many C-based event loops do not handle	608	C<send>.
586	overloading, so as tempting as it may be, passing a condition variable
587	instead of a callback does not work. Both the pure perl and EV loops
588	support overloading, however, as well as all functions that use perl to
589	invoke a callback (as in L<AnyEvent::Socket> and L<AnyEvent::DNS> for
590	example).
591		609
592	=item $cv->croak ($error)	610	=item $cv->croak ($error)
593		611
594	Similar to send, but causes all call's to C<< ->recv >> to invoke	612	Similar to send, but causes all call's to C<< ->recv >> to invoke
595	C<Carp::croak> with the given error message/object/scalar.	613	C<Carp::croak> with the given error message/object/scalar.
596		614
597	This can be used to signal any errors to the condition variable	615	This can be used to signal any errors to the condition variable
598	user/consumer.	616	user/consumer. Doing it this way instead of calling C<croak> directly
		617	delays the error detetcion, but has the overwhelmign advantage that it
		618	diagnoses the error at the place where the result is expected, and not
		619	deep in some event clalback without connection to the actual code causing
		620	the problem.
599		621
600	=item $cv->begin ([group callback])	622	=item $cv->begin ([group callback])
601		623
602	=item $cv->end	624	=item $cv->end
603		625
…		…
699	function will call C<croak>.	721	function will call C<croak>.
700		722
701	In list context, all parameters passed to C<send> will be returned,	723	In list context, all parameters passed to C<send> will be returned,
702	in scalar context only the first one will be returned.	724	in scalar context only the first one will be returned.
703		725
		726	Note that doing a blocking wait in a callback is not supported by any
		727	event loop, that is, recursive invocation of a blocking C<< ->recv
		728	>> is not allowed, and the C<recv> call will C<croak> if such a
		729	condition is detected. This condition can be slightly loosened by using
		730	L<Coro::AnyEvent>, which allows you to do a blocking C<< ->recv >> from
		731	any thread that doesn't run the event loop itself.
		732
704	Not all event models support a blocking wait - some die in that case	733	Not all event models support a blocking wait - some die in that case
705	(programs might want to do that to stay interactive), so I<if you are	734	(programs might want to do that to stay interactive), so I<if you are
706	using this from a module, never require a blocking wait>, but let the	735	using this from a module, never require a blocking wait>. Instead, let the
707	caller decide whether the call will block or not (for example, by coupling	736	caller decide whether the call will block or not (for example, by coupling
708	condition variables with some kind of request results and supporting	737	condition variables with some kind of request results and supporting
709	callbacks so the caller knows that getting the result will not block,	738	callbacks so the caller knows that getting the result will not block,
710	while still supporting blocking waits if the caller so desires).	739	while still supporting blocking waits if the caller so desires).
711		740
712	Another reason I<never> to C<< ->recv >> in a module is that you cannot
713	sensibly have two C<< ->recv >>'s in parallel, as that would require
714	multiple interpreters or coroutines/threads, none of which C<AnyEvent>
715	can supply.
716
717	The L<Coro> module, however, I<can> and I<does> supply coroutines and, in
718	fact, L<Coro::AnyEvent> replaces AnyEvent's condvars by coroutine-safe
719	versions and also integrates coroutines into AnyEvent, making blocking
720	C<< ->recv >> calls perfectly safe as long as they are done from another
721	coroutine (one that doesn't run the event loop).
722
723	You can ensure that C<< -recv >> never blocks by setting a callback and	741	You can ensure that C<< -recv >> never blocks by setting a callback and
724	only calling C<< ->recv >> from within that callback (or at a later	742	only calling C<< ->recv >> from within that callback (or at a later
725	time). This will work even when the event loop does not support blocking	743	time). This will work even when the event loop does not support blocking
726	waits otherwise.	744	waits otherwise.
727		745
…		…
740	variable itself. Calling C<recv> inside the callback or at any later time	758	variable itself. Calling C<recv> inside the callback or at any later time
741	is guaranteed not to block.	759	is guaranteed not to block.
742		760
743	=back	761	=back
744		762
		763	=head1 SUPPORTED EVENT LOOPS/BACKENDS
		764
		765	The available backend classes are (every class has its own manpage):
		766
		767	=over 4
		768
		769	=item Backends that are autoprobed when no other event loop can be found.
		770
		771	EV is the preferred backend when no other event loop seems to be in
		772	use. If EV is not installed, then AnyEvent will try Event, and, failing
		773	that, will fall back to its own pure-perl implementation, which is
		774	available everywhere as it comes with AnyEvent itself.
		775
		776	AnyEvent::Impl::EV based on EV (interface to libev, best choice).
		777	AnyEvent::Impl::Event based on Event, very stable, few glitches.
		778	AnyEvent::Impl::Perl pure-perl implementation, fast and portable.
		779
		780	=item Backends that are transparently being picked up when they are used.
		781
		782	These will be used when they are currently loaded when the first watcher
		783	is created, in which case it is assumed that the application is using
		784	them. This means that AnyEvent will automatically pick the right backend
		785	when the main program loads an event module before anything starts to
		786	create watchers. Nothing special needs to be done by the main program.
		787
		788	AnyEvent::Impl::Glib based on Glib, slow but very stable.
		789	AnyEvent::Impl::Tk based on Tk, very broken.
		790	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
		791	AnyEvent::Impl::POE based on POE, very slow, some limitations.
		792
		793	=item Backends with special needs.
		794
		795	Qt requires the Qt::Application to be instantiated first, but will
		796	otherwise be picked up automatically. As long as the main program
		797	instantiates the application before any AnyEvent watchers are created,
		798	everything should just work.
		799
		800	AnyEvent::Impl::Qt based on Qt.
		801
		802	Support for IO::Async can only be partial, as it is too broken and
		803	architecturally limited to even support the AnyEvent API. It also
		804	is the only event loop that needs the loop to be set explicitly, so
		805	it can only be used by a main program knowing about AnyEvent. See
		806	L<AnyEvent::Impl::Async> for the gory details.
		807
		808	AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed.
		809
		810	=item Event loops that are indirectly supported via other backends.
		811
		812	Some event loops can be supported via other modules:
		813
		814	There is no direct support for WxWidgets (L<Wx>) or L<Prima>.
		815
		816	B<WxWidgets> has no support for watching file handles. However, you can
		817	use WxWidgets through the POE adaptor, as POE has a Wx backend that simply
		818	polls 20 times per second, which was considered to be too horrible to even
		819	consider for AnyEvent.
		820
		821	B<Prima> is not supported as nobody seems to be using it, but it has a POE
		822	backend, so it can be supported through POE.
		823
		824	AnyEvent knows about both L<Prima> and L<Wx>, however, and will try to
		825	load L<POE> when detecting them, in the hope that POE will pick them up,
		826	in which case everything will be automatic.
		827
		828	=back
		829
745	=head1 GLOBAL VARIABLES AND FUNCTIONS	830	=head1 GLOBAL VARIABLES AND FUNCTIONS
746		831
		832	These are not normally required to use AnyEvent, but can be useful to
		833	write AnyEvent extension modules.
		834
747	=over 4	835	=over 4
748		836
749	=item $AnyEvent::MODEL	837	=item $AnyEvent::MODEL
750		838
751	Contains C<undef> until the first watcher is being created. Then it	839	Contains C<undef> until the first watcher is being created, before the
		840	backend has been autodetected.
		841
752	contains the event model that is being used, which is the name of the	842	Afterwards it contains the event model that is being used, which is the
753	Perl class implementing the model. This class is usually one of the	843	name of the Perl class implementing the model. This class is usually one
754	C<AnyEvent::Impl:xxx> modules, but can be any other class in the case	844	of the C<AnyEvent::Impl:xxx> modules, but can be any other class in the
755	AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode>).	845	case AnyEvent has been extended at runtime (e.g. in I<rxvt-unicode> it
756		846	will be C<urxvt::anyevent>).
757	The known classes so far are:
758
759	AnyEvent::Impl::EV based on EV (an interface to libev, best choice).
760	AnyEvent::Impl::Event based on Event, second best choice.
761	AnyEvent::Impl::Perl pure-perl implementation, fast and portable.
762	AnyEvent::Impl::Glib based on Glib, third-best choice.
763	AnyEvent::Impl::Tk based on Tk, very bad choice.
764	AnyEvent::Impl::Qt based on Qt, cannot be autoprobed (see its docs).
765	AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse.
766	AnyEvent::Impl::POE based on POE, not generic enough for full support.
767
768	# warning, support for IO::Async is only partial, as it is too broken
769	# and limited toe ven support the AnyEvent API. See AnyEvent::Impl::Async.
770	AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed (see its docs).
771
772	There is no support for WxWidgets, as WxWidgets has no support for
773	watching file handles. However, you can use WxWidgets through the
774	POE Adaptor, as POE has a Wx backend that simply polls 20 times per
775	second, which was considered to be too horrible to even consider for
776	AnyEvent. Likewise, other POE backends can be used by AnyEvent by using
777	it's adaptor.
778
779	AnyEvent knows about L<Prima> and L<Wx> and will try to use L<POE> when
780	autodetecting them.
781		847
782	=item AnyEvent::detect	848	=item AnyEvent::detect
783		849
784	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model	850	Returns C<$AnyEvent::MODEL>, forcing autodetection of the event model
785	if necessary. You should only call this function right before you would	851	if necessary. You should only call this function right before you would
786	have created an AnyEvent watcher anyway, that is, as late as possible at	852	have created an AnyEvent watcher anyway, that is, as late as possible at
787	runtime.	853	runtime, and not e.g. while initialising of your module.
		854
		855	If you need to do some initialisation before AnyEvent watchers are
		856	created, use C<post_detect>.
788		857
789	=item $guard = AnyEvent::post_detect { BLOCK }	858	=item $guard = AnyEvent::post_detect { BLOCK }
790		859
791	Arranges for the code block to be executed as soon as the event model is	860	Arranges for the code block to be executed as soon as the event model is
792	autodetected (or immediately if this has already happened).	861	autodetected (or immediately if this has already happened).
		862
		863	The block will be executed I<after> the actual backend has been detected
		864	(C<$AnyEvent::MODEL> is set), but I<before> any watchers have been
		865	created, so it is possible to e.g. patch C<@AnyEvent::ISA> or do
		866	other initialisations - see the sources of L<AnyEvent::Strict> or
		867	L<AnyEvent::AIO> to see how this is used.
		868
		869	The most common usage is to create some global watchers, without forcing
		870	event module detection too early, for example, L<AnyEvent::AIO> creates
		871	and installs the global L<IO::AIO> watcher in a C<post_detect> block to
		872	avoid autodetecting the event module at load time.
793		873
794	If called in scalar or list context, then it creates and returns an object	874	If called in scalar or list context, then it creates and returns an object
795	that automatically removes the callback again when it is destroyed. See	875	that automatically removes the callback again when it is destroyed. See
796	L<Coro::BDB> for a case where this is useful.	876	L<Coro::BDB> for a case where this is useful.
797		877
…		…
800	If there are any code references in this array (you can C<push> to it	880	If there are any code references in this array (you can C<push> to it
801	before or after loading AnyEvent), then they will called directly after	881	before or after loading AnyEvent), then they will called directly after
802	the event loop has been chosen.	882	the event loop has been chosen.
803		883
804	You should check C<$AnyEvent::MODEL> before adding to this array, though:	884	You should check C<$AnyEvent::MODEL> before adding to this array, though:
805	if it contains a true value then the event loop has already been detected,	885	if it is defined then the event loop has already been detected, and the
806	and the array will be ignored.	886	array will be ignored.
807		887
808	Best use C<AnyEvent::post_detect { BLOCK }> instead.	888	Best use C<AnyEvent::post_detect { BLOCK }> when your application allows
		889	it,as it takes care of these details.
		890
		891	This variable is mainly useful for modules that can do something useful
		892	when AnyEvent is used and thus want to know when it is initialised, but do
		893	not need to even load it by default. This array provides the means to hook
		894	into AnyEvent passively, without loading it.
809		895
810	=back	896	=back
811		897
812	=head1 WHAT TO DO IN A MODULE	898	=head1 WHAT TO DO IN A MODULE
813		899
…		…
868		954
869		955
870	=head1 OTHER MODULES	956	=head1 OTHER MODULES
871		957
872	The following is a non-exhaustive list of additional modules that use	958	The following is a non-exhaustive list of additional modules that use
873	AnyEvent and can therefore be mixed easily with other AnyEvent modules	959	AnyEvent as a client and can therefore be mixed easily with other AnyEvent
874	in the same program. Some of the modules come with AnyEvent, some are	960	modules and other event loops in the same program. Some of the modules
875	available via CPAN.	961	come with AnyEvent, most are available via CPAN.
876		962
877	=over 4	963	=over 4
878		964
879	=item L<AnyEvent::Util>	965	=item L<AnyEvent::Util>
880		966
…		…
889		975
890	=item L<AnyEvent::Handle>	976	=item L<AnyEvent::Handle>
891		977
892	Provide read and write buffers, manages watchers for reads and writes,	978	Provide read and write buffers, manages watchers for reads and writes,
893	supports raw and formatted I/O, I/O queued and fully transparent and	979	supports raw and formatted I/O, I/O queued and fully transparent and
894	non-blocking SSL/TLS.	980	non-blocking SSL/TLS (via L<AnyEvent::TLS>.
895		981
896	=item L<AnyEvent::DNS>	982	=item L<AnyEvent::DNS>
897		983
898	Provides rich asynchronous DNS resolver capabilities.	984	Provides rich asynchronous DNS resolver capabilities.
899		985
…		…
927		1013
928	=item L<AnyEvent::GPSD>	1014	=item L<AnyEvent::GPSD>
929		1015
930	A non-blocking interface to gpsd, a daemon delivering GPS information.	1016	A non-blocking interface to gpsd, a daemon delivering GPS information.
931		1017
		1018	=item L<AnyEvent::IRC>
		1019
		1020	AnyEvent based IRC client module family (replacing the older Net::IRC3).
		1021
		1022	=item L<AnyEvent::XMPP>
		1023
		1024	AnyEvent based XMPP (Jabber protocol) module family (replacing the older
		1025	Net::XMPP2>.
		1026
932	=item L<AnyEvent::IGS>	1027	=item L<AnyEvent::IGS>
933		1028
934	A non-blocking interface to the Internet Go Server protocol (used by	1029	A non-blocking interface to the Internet Go Server protocol (used by
935	L<App::IGS>).	1030	L<App::IGS>).
936		1031
937	=item L<AnyEvent::IRC>
938
939	AnyEvent based IRC client module family (replacing the older Net::IRC3).
940
941	=item L<Net::XMPP2>
942
943	AnyEvent based XMPP (Jabber protocol) module family.
944
945	=item L<Net::FCP>	1032	=item L<Net::FCP>
946		1033
947	AnyEvent-based implementation of the Freenet Client Protocol, birthplace	1034	AnyEvent-based implementation of the Freenet Client Protocol, birthplace
948	of AnyEvent.	1035	of AnyEvent.
949		1036
…		…
953		1040
954	=item L<Coro>	1041	=item L<Coro>
955		1042
956	Has special support for AnyEvent via L<Coro::AnyEvent>.	1043	Has special support for AnyEvent via L<Coro::AnyEvent>.
957		1044
958	=item L<IO::Lambda>
959
960	The lambda approach to I/O - don't ask, look there. Can use AnyEvent.
961
962	=back	1045	=back
963		1046
964	=cut	1047	=cut
965		1048
966	package AnyEvent;	1049	package AnyEvent;
967		1050
		1051	# basically a tuned-down version of common::sense
		1052	sub common_sense {
968	no warnings;	1053	# no warnings
		1054	${^WARNING_BITS} ^= ${^WARNING_BITS};
969	use strict qw(vars subs);	1055	# use strict vars subs
		1056	$^H \|= 0x00000600;
		1057	}
970		1058
		1059	BEGIN { AnyEvent::common_sense }
		1060
971	use Carp;	1061	use Carp ();
972		1062
973	our $VERSION = 4.452;	1063	our $VERSION = 4.85;
974	our $MODEL;	1064	our $MODEL;
975		1065
976	our $AUTOLOAD;	1066	our $AUTOLOAD;
977	our @ISA;	1067	our @ISA;
978		1068
979	our @REGISTRY;	1069	our @REGISTRY;
980		1070
981	our $WIN32;	1071	our $WIN32;
		1072
		1073	our $VERBOSE;
982		1074
983	BEGIN {	1075	BEGIN {
984	eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }";	1076	eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }";
985	eval "sub TAINT(){ " . (${^TAINT}*1) . " }";	1077	eval "sub TAINT(){ " . (${^TAINT}*1) . " }";
986		1078
987	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}	1079	delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV}
988	if ${^TAINT};	1080	if ${^TAINT};
989	}
990		1081
991	our $verbose = $ENV{PERL_ANYEVENT_VERBOSE}*1;	1082	$VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1;
		1083
		1084	}
		1085
		1086	our $MAX_SIGNAL_LATENCY = 10;
992		1087
993	our %PROTOCOL; # (ipv4\|ipv6) => (1\|2), higher numbers are preferred	1088	our %PROTOCOL; # (ipv4\|ipv6) => (1\|2), higher numbers are preferred
994		1089
995	{	1090	{
996	my $idx;	1091	my $idx;
…		…
1004	[Event:: => AnyEvent::Impl::Event::],	1099	[Event:: => AnyEvent::Impl::Event::],
1005	[AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::],	1100	[AnyEvent::Impl::Perl:: => AnyEvent::Impl::Perl::],
1006	# everything below here will not be autoprobed	1101	# everything below here will not be autoprobed
1007	# as the pureperl backend should work everywhere	1102	# as the pureperl backend should work everywhere
1008	# and is usually faster	1103	# and is usually faster
1009	[Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
1010	[Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers	1104	[Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers
1011	[Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy	1105	[Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
		1106	[Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
1012	[Qt:: => AnyEvent::Impl::Qt::], # requires special main program	1107	[Qt:: => AnyEvent::Impl::Qt::], # requires special main program
1013	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza	1108	[POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
1014	[Wx:: => AnyEvent::Impl::POE::],	1109	[Wx:: => AnyEvent::Impl::POE::],
1015	[Prima:: => AnyEvent::Impl::POE::],	1110	[Prima:: => AnyEvent::Impl::POE::],
1016	# IO::Async is just too broken - we would need workaorunds for its	1111	# IO::Async is just too broken - we would need workarounds for its
1017	# byzantine signal and broken child handling, among others.	1112	# byzantine signal and broken child handling, among others.
1018	# IO::Async is rather hard to detect, as it doesn't have any	1113	# IO::Async is rather hard to detect, as it doesn't have any
1019	# obvious default class.	1114	# obvious default class.
1020	# [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program	1115	# [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program
1021	# [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program	1116	# [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program
…		…
1047	@post_detect = grep $_ != ${$_[0]}, @post_detect;	1142	@post_detect = grep $_ != ${$_[0]}, @post_detect;
1048	}	1143	}
1049		1144
1050	sub detect() {	1145	sub detect() {
1051	unless ($MODEL) {	1146	unless ($MODEL) {
1052	no strict 'refs';
1053	local $SIG{__DIE__};	1147	local $SIG{__DIE__};
1054		1148
1055	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {	1149	if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) {
1056	my $model = "AnyEvent::Impl::$1";	1150	my $model = "AnyEvent::Impl::$1";
1057	if (eval "require $model") {	1151	if (eval "require $model") {
1058	$MODEL = $model;	1152	$MODEL = $model;
1059	warn "AnyEvent: loaded model '$model' (forced by \$PERL_ANYEVENT_MODEL), using it.\n" if $verbose > 1;	1153	warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2;
1060	} else {	1154	} else {
1061	warn "AnyEvent: unable to load model '$model' (from \$PERL_ANYEVENT_MODEL):\n$@" if $verbose;	1155	warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE;
1062	}	1156	}
1063	}	1157	}
1064		1158
1065	# check for already loaded models	1159	# check for already loaded models
1066	unless ($MODEL) {	1160	unless ($MODEL) {
1067	for (@REGISTRY, @models) {	1161	for (@REGISTRY, @models) {
1068	my ($package, $model) = @$_;	1162	my ($package, $model) = @$_;
1069	if (${"$package\::VERSION"} > 0) {	1163	if (${"$package\::VERSION"} > 0) {
1070	if (eval "require $model") {	1164	if (eval "require $model") {
1071	$MODEL = $model;	1165	$MODEL = $model;
1072	warn "AnyEvent: autodetected model '$model', using it.\n" if $verbose > 1;	1166	warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2;
1073	last;	1167	last;
1074	}	1168	}
1075	}	1169	}
1076	}	1170	}
1077		1171
…		…
1082	my ($package, $model) = @$_;	1176	my ($package, $model) = @$_;
1083	if (eval "require $package"	1177	if (eval "require $package"
1084	and ${"$package\::VERSION"} > 0	1178	and ${"$package\::VERSION"} > 0
1085	and eval "require $model") {	1179	and eval "require $model") {
1086	$MODEL = $model;	1180	$MODEL = $model;
1087	warn "AnyEvent: autoprobed model '$model', using it.\n" if $verbose > 1;	1181	warn "AnyEvent: autoprobed model '$model', using it.\n" if $VERBOSE >= 2;
1088	last;	1182	last;
1089	}	1183	}
1090	}	1184	}
1091		1185
1092	$MODEL	1186	$MODEL
…		…
1108		1202
1109	sub AUTOLOAD {	1203	sub AUTOLOAD {
1110	(my $func = $AUTOLOAD) =~ s/.*://;	1204	(my $func = $AUTOLOAD) =~ s/.*://;
1111		1205
1112	$method{$func}	1206	$method{$func}
1113	or croak "$func: not a valid method for AnyEvent objects";	1207	or Carp::croak "$func: not a valid method for AnyEvent objects";
1114		1208
1115	detect unless $MODEL;	1209	detect unless $MODEL;
1116		1210
1117	my $class = shift;	1211	my $class = shift;
1118	$class->$func (@_);	1212	$class->$func (@_);
…		…
1123	# allow only one watcher per fd, so we dup it to get a different one).	1217	# allow only one watcher per fd, so we dup it to get a different one).
1124	sub _dupfh($$;$$) {	1218	sub _dupfh($$;$$) {
1125	my ($poll, $fh, $r, $w) = @_;	1219	my ($poll, $fh, $r, $w) = @_;
1126		1220
1127	# cygwin requires the fh mode to be matching, unix doesn't	1221	# cygwin requires the fh mode to be matching, unix doesn't
1128	my ($rw, $mode) = $poll eq "r" ? ($r, "<")	1222	my ($rw, $mode) = $poll eq "r" ? ($r, "<&") : ($w, ">&");
1129	: $poll eq "w" ? ($w, ">")
1130	: Carp::croak "AnyEvent->io requires poll set to either 'r' or 'w'";
1131		1223
1132	open my $fh2, "$mode&" . fileno $fh	1224	open my $fh2, $mode, $fh
1133	or die "cannot dup() filehandle: $!,";	1225	or die "AnyEvent->io: cannot dup() filehandle in mode '$poll': $!,";
1134		1226
1135	# we assume CLOEXEC is already set by perl in all important cases	1227	# we assume CLOEXEC is already set by perl in all important cases
1136		1228
1137	($fh2, $rw)	1229	($fh2, $rw)
1138	}	1230	}
1139		1231
1140	package AnyEvent::Base;	1232	package AnyEvent::Base;
1141		1233
1142	# default implementations for many methods	1234	# default implementations for many methods
1143		1235
1144	BEGIN {	1236	sub _time {
		1237	# probe for availability of Time::HiRes
1145	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {	1238	if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
		1239	warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8;
1146	*_time = \&Time::HiRes::time;	1240	*_time = \&Time::HiRes::time;
1147	# if (eval "use POSIX (); (POSIX::times())...	1241	# if (eval "use POSIX (); (POSIX::times())...
1148	} else {	1242	} else {
		1243	warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE;
1149	*_time = sub { time }; # epic fail	1244	*_time = sub { time }; # epic fail
1150	}	1245	}
		1246
		1247	&_time
1151	}	1248	}
1152		1249
1153	sub time { _time }	1250	sub time { _time }
1154	sub now { _time }	1251	sub now { _time }
1155	sub now_update { }	1252	sub now_update { }
…		…
1160	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"	1257	bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar"
1161	}	1258	}
1162		1259
1163	# default implementation for ->signal	1260	# default implementation for ->signal
1164		1261
		1262	our $HAVE_ASYNC_INTERRUPT;
1165	our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);	1263	our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO);
		1264	our (%SIG_ASY, %SIG_ASY_W);
		1265	our ($SIG_COUNT, $SIG_TW);
1166		1266
1167	sub _signal_exec {	1267	sub _signal_exec {
		1268	$HAVE_ASYNC_INTERRUPT
		1269	? $SIGPIPE_R->drain
1168	sysread $SIGPIPE_R, my $dummy, 4;	1270	: sysread $SIGPIPE_R, my $dummy, 9;
1169		1271
1170	while (%SIG_EV) {	1272	while (%SIG_EV) {
1171	for (keys %SIG_EV) {	1273	for (keys %SIG_EV) {
1172	delete $SIG_EV{$_};	1274	delete $SIG_EV{$_};
1173	$_->() for values %{ $SIG_CB{$_} \|\| {} };	1275	$_->() for values %{ $SIG_CB{$_} \|\| {} };
1174	}	1276	}
1175	}	1277	}
1176	}	1278	}
1177		1279
		1280	# install a dumym wakeupw atcher to reduce signal catching latency
		1281	sub _sig_add() {
		1282	unless ($SIG_COUNT++) {
		1283	# try to align timer on a full-second boundary, if possible
		1284	my $NOW = AnyEvent->now;
		1285
		1286	$SIG_TW = AnyEvent->timer (
		1287	after => $MAX_SIGNAL_LATENCY - ($NOW - int $NOW),
		1288	interval => $MAX_SIGNAL_LATENCY,
		1289	cb => sub { }, # just for the PERL_ASYNC_CHECK
		1290	);
		1291	}
		1292	}
		1293
		1294	sub _sig_del {
		1295	undef $SIG_TW
		1296	unless --$SIG_COUNT;
		1297	}
		1298
		1299	sub _signal {
		1300	my (undef, %arg) = @_;
		1301
		1302	my $signal = uc $arg{signal}
		1303	or Carp::croak "required option 'signal' is missing";
		1304
		1305	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};
		1306
		1307	if ($HAVE_ASYNC_INTERRUPT) {
		1308	# async::interrupt
		1309
		1310	$SIG_ASY{$signal} \|\|= do {
		1311	my $asy = new Async::Interrupt
		1312	cb => sub { undef $SIG_EV{$signal} },
		1313	signal => $signal,
		1314	pipe => [$SIGPIPE_R->filenos],
		1315	;
		1316	$asy->pipe_autodrain (0);
		1317
		1318	$asy
		1319	};
		1320
		1321	} else {
		1322	# pure perl
		1323
		1324	$SIG{$signal} \|\|= sub {
		1325	local $!;
		1326	syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
		1327	undef $SIG_EV{$signal};
		1328	};
		1329
		1330	# can't do signal processing without introducing races in pure perl,
		1331	# so limit the signal latency.
		1332	_sig_add;
		1333	}
		1334
		1335	bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
		1336	}
		1337
1178	sub signal {	1338	sub signal {
1179	my (undef, %arg) = @_;	1339	# probe for availability of Async::Interrupt
		1340	if (!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT} && eval "use Async::Interrupt 0.6 (); 1") {
		1341	warn "AnyEvent: using Async::Interrupt for race-free signal handling.\n" if $VERBOSE >= 8;
1180		1342
1181	unless ($SIGPIPE_R) {	1343	$HAVE_ASYNC_INTERRUPT = 1;
		1344	$SIGPIPE_R = new Async::Interrupt::EventPipe;
		1345	$SIG_IO = AnyEvent->io (fh => $SIGPIPE_R->fileno, poll => "r", cb => \&_signal_exec);
		1346
		1347	} else {
		1348	warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8;
		1349
1182	require Fcntl;	1350	require Fcntl;
1183		1351
1184	if (AnyEvent::WIN32) {	1352	if (AnyEvent::WIN32) {
1185	require AnyEvent::Util;	1353	require AnyEvent::Util;
1186		1354
…		…
1201	or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";	1369	or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n";
1202		1370
1203	$SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec);	1371	$SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec);
1204	}	1372	}
1205		1373
1206	my $signal = uc $arg{signal}	1374	*signal = \&_signal;
1207	or Carp::croak "required option 'signal' is missing";	1375	&signal
1208
1209	$SIG_CB{$signal}{$arg{cb}} = $arg{cb};
1210	$SIG{$signal} \|\|= sub {
1211	local $!;
1212	syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV;
1213	undef $SIG_EV{$signal};
1214	};
1215
1216	bless [$signal, $arg{cb}], "AnyEvent::Base::signal"
1217	}	1376	}
1218		1377
1219	sub AnyEvent::Base::signal::DESTROY {	1378	sub AnyEvent::Base::signal::DESTROY {
1220	my ($signal, $cb) = @{$_[0]};	1379	my ($signal, $cb) = @{$_[0]};
1221		1380
		1381	_sig_del;
		1382
1222	delete $SIG_CB{$signal}{$cb};	1383	delete $SIG_CB{$signal}{$cb};
1223		1384
		1385	$HAVE_ASYNC_INTERRUPT
		1386	? delete $SIG_ASY{$signal}
1224	# delete doesn't work with older perls - they then	1387	: # delete doesn't work with older perls - they then
1225	# print weird messages, or just unconditionally exit	1388	# print weird messages, or just unconditionally exit
1226	# instead of getting the default action.	1389	# instead of getting the default action.
		1390	undef $SIG{$signal}
1227	undef $SIG{$signal} unless keys %{ $SIG_CB{$signal} };	1391	unless keys %{ $SIG_CB{$signal} };
1228	}	1392	}
1229		1393
1230	# default implementation for ->child	1394	# default implementation for ->child
1231		1395
1232	our %PID_CB;	1396	our %PID_CB;
…		…
1234	our $CHLD_DELAY_W;	1398	our $CHLD_DELAY_W;
1235	our $WNOHANG;	1399	our $WNOHANG;
1236		1400
1237	sub _sigchld {	1401	sub _sigchld {
1238	while (0 < (my $pid = waitpid -1, $WNOHANG)) {	1402	while (0 < (my $pid = waitpid -1, $WNOHANG)) {
		1403	$_->($pid, $?)
1239	$_->($pid, $?) for (values %{ $PID_CB{$pid} \|\| {} }),	1404	for values %{ $PID_CB{$pid} \|\| {} },
1240	(values %{ $PID_CB{0} \|\| {} });	1405	values %{ $PID_CB{0} \|\| {} };
1241	}	1406	}
1242	}	1407	}
1243		1408
1244	sub child {	1409	sub child {
1245	my (undef, %arg) = @_;	1410	my (undef, %arg) = @_;
…		…
1247	defined (my $pid = $arg{pid} + 0)	1412	defined (my $pid = $arg{pid} + 0)
1248	or Carp::croak "required option 'pid' is missing";	1413	or Carp::croak "required option 'pid' is missing";
1249		1414
1250	$PID_CB{$pid}{$arg{cb}} = $arg{cb};	1415	$PID_CB{$pid}{$arg{cb}} = $arg{cb};
1251		1416
		1417	# WNOHANG is almost cetrainly 1 everywhere
		1418	$WNOHANG \|\|= $^O =~ /^(?:openbsd\|netbsd\|linux\|freebsd\|cygwin\|MSWin32)$/
		1419	? 1
1252	$WNOHANG \|\|= eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } \|\| 1;	1420	: eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } \|\| 1;
1253		1421
1254	unless ($CHLD_W) {	1422	unless ($CHLD_W) {
1255	$CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld);	1423	$CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld);
1256	# child could be a zombie already, so make at least one round	1424	# child could be a zombie already, so make at least one round
1257	&_sigchld;	1425	&_sigchld;
…		…
1309		1477
1310	our @ISA = AnyEvent::CondVar::Base::;	1478	our @ISA = AnyEvent::CondVar::Base::;
1311		1479
1312	package AnyEvent::CondVar::Base;	1480	package AnyEvent::CondVar::Base;
1313		1481
1314	use overload	1482	#use overload
1315	'&{}' => sub { my $self = shift; sub { $self->send (@_) } },	1483	# '&{}' => sub { my $self = shift; sub { $self->send (@_) } },
1316	fallback => 1;	1484	# fallback => 1;
		1485
		1486	# save 300+ kilobytes by dirtily hardcoding overloading
		1487	${"AnyEvent::CondVar::Base::OVERLOAD"}{dummy}++; # Register with magic by touching.
		1488	*{'AnyEvent::CondVar::Base::()'} = sub { }; # "Make it findable via fetchmethod."
		1489	*{'AnyEvent::CondVar::Base::(&{}'} = sub { my $self = shift; sub { $self->send (@_) } }; # &{}
		1490	${'AnyEvent::CondVar::Base::()'} = 1; # fallback
		1491
		1492	our $WAITING;
1317		1493
1318	sub _send {	1494	sub _send {
1319	# nop	1495	# nop
1320	}	1496	}
1321		1497
…		…
1334	sub ready {	1510	sub ready {
1335	$_[0]{_ae_sent}	1511	$_[0]{_ae_sent}
1336	}	1512	}
1337		1513
1338	sub _wait {	1514	sub _wait {
		1515	$WAITING
		1516	and !$_[0]{_ae_sent}
		1517	and Carp::croak "AnyEvent::CondVar: recursive blocking wait detected";
		1518
		1519	local $WAITING = 1;
1339	AnyEvent->one_event while !$_[0]{_ae_sent};	1520	AnyEvent->one_event while !$_[0]{_ae_sent};
1340	}	1521	}
1341		1522
1342	sub recv {	1523	sub recv {
1343	$_[0]->_wait;	1524	$_[0]->_wait;
…		…
1405	C<PERL_ANYEVENT_MODEL>.	1586	C<PERL_ANYEVENT_MODEL>.
1406		1587
1407	When set to C<2> or higher, cause AnyEvent to report to STDERR which event	1588	When set to C<2> or higher, cause AnyEvent to report to STDERR which event
1408	model it chooses.	1589	model it chooses.
1409		1590
		1591	When set to C<8> or higher, then AnyEvent will report extra information on
		1592	which optional modules it loads and how it implements certain features.
		1593
1410	=item C<PERL_ANYEVENT_STRICT>	1594	=item C<PERL_ANYEVENT_STRICT>
1411		1595
1412	AnyEvent does not do much argument checking by default, as thorough	1596	AnyEvent does not do much argument checking by default, as thorough
1413	argument checking is very costly. Setting this variable to a true value	1597	argument checking is very costly. Setting this variable to a true value
1414	will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly	1598	will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly
1415	check the arguments passed to most method calls. If it finds any problems,	1599	check the arguments passed to most method calls. If it finds any problems,
1416	it will croak.	1600	it will croak.
1417		1601
1418	In other words, enables "strict" mode.	1602	In other words, enables "strict" mode.
1419		1603
1420	Unlike C<use strict>, it is definitely recommended to keep it off in	1604	Unlike C<use strict> (or it's modern cousin, C<< use L<common::sense>
1421	production. Keeping C<PERL_ANYEVENT_STRICT=1> in your environment while	1605	>>, it is definitely recommended to keep it off in production. Keeping
1422	developing programs can be very useful, however.	1606	C<PERL_ANYEVENT_STRICT=1> in your environment while developing programs
		1607	can be very useful, however.
1423		1608
1424	=item C<PERL_ANYEVENT_MODEL>	1609	=item C<PERL_ANYEVENT_MODEL>
1425		1610
1426	This can be used to specify the event model to be used by AnyEvent, before	1611	This can be used to specify the event model to be used by AnyEvent, before
1427	auto detection and -probing kicks in. It must be a string consisting	1612	auto detection and -probing kicks in. It must be a string consisting
…		…
1470		1655
1471	=item C<PERL_ANYEVENT_MAX_FORKS>	1656	=item C<PERL_ANYEVENT_MAX_FORKS>
1472		1657
1473	The maximum number of child processes that C<AnyEvent::Util::fork_call>	1658	The maximum number of child processes that C<AnyEvent::Util::fork_call>
1474	will create in parallel.	1659	will create in parallel.
		1660
		1661	=item C<PERL_ANYEVENT_MAX_OUTSTANDING_DNS>
		1662
		1663	The default value for the C<max_outstanding> parameter for the default DNS
		1664	resolver - this is the maximum number of parallel DNS requests that are
		1665	sent to the DNS server.
		1666
		1667	=item C<PERL_ANYEVENT_RESOLV_CONF>
		1668
		1669	The file to use instead of F</etc/resolv.conf> (or OS-specific
		1670	configuration) in the default resolver. When set to the empty string, no
		1671	default config will be used.
		1672
		1673	=item C<PERL_ANYEVENT_CA_FILE>, C<PERL_ANYEVENT_CA_PATH>.
		1674
		1675	When neither C<ca_file> nor C<ca_path> was specified during
		1676	L<AnyEvent::TLS> context creation, and either of these environment
		1677	variables exist, they will be used to specify CA certificate locations
		1678	instead of a system-dependent default.
		1679
		1680	=item C<PERL_ANYEVENT_AVOID_GUARD> and C<PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT>
		1681
		1682	When these are set to C<1>, then the respective modules are not
		1683	loaded. Mostly good for testing AnyEvent itself.
1475		1684
1476	=back	1685	=back
1477		1686
1478	=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE	1687	=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE
1479		1688
…		…
2018		2227
2019	A handler for C<SIGCHLD> is installed by AnyEvent's child watcher	2228	A handler for C<SIGCHLD> is installed by AnyEvent's child watcher
2020	emulation for event loops that do not support them natively. Also, some	2229	emulation for event loops that do not support them natively. Also, some
2021	event loops install a similar handler.	2230	event loops install a similar handler.
2022		2231
2023	If, when AnyEvent is loaded, SIGCHLD is set to IGNORE, then AnyEvent will	2232	Additionally, when AnyEvent is loaded and SIGCHLD is set to IGNORE, then
2024	reset it to default, to avoid losing child exit statuses.	2233	AnyEvent will reset it to default, to avoid losing child exit statuses.
2025		2234
2026	=item SIGPIPE	2235	=item SIGPIPE
2027		2236
2028	A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef>	2237	A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef>
2029	when AnyEvent gets loaded.	2238	when AnyEvent gets loaded.
…		…
2047	if $SIG{CHLD} eq 'IGNORE';	2256	if $SIG{CHLD} eq 'IGNORE';
2048		2257
2049	$SIG{PIPE} = sub { }	2258	$SIG{PIPE} = sub { }
2050	unless defined $SIG{PIPE};	2259	unless defined $SIG{PIPE};
2051		2260
		2261	=head1 RECOMMENDED/OPTIONAL MODULES
		2262
		2263	One of AnyEvent's main goals is to be 100% Pure-Perl(tm): only perl (and
		2264	it's built-in modules) are required to use it.
		2265
		2266	That does not mean that AnyEvent won't take advantage of some additional
		2267	modules if they are installed.
		2268
		2269	This section epxlains which additional modules will be used, and how they
		2270	affect AnyEvent's operetion.
		2271
		2272	=over 4
		2273
		2274	=item L<Async::Interrupt>
		2275
		2276	This slightly arcane module is used to implement fast signal handling: To
		2277	my knowledge, there is no way to do completely race-free and quick
		2278	signal handling in pure perl. To ensure that signals still get
		2279	delivered, AnyEvent will start an interval timer to wake up perl (and
		2280	catch the signals) with some delay (default is 10 seconds, look for
		2281	C<$AnyEvent::MAX_SIGNAL_LATENCY>).
		2282
		2283	If this module is available, then it will be used to implement signal
		2284	catching, which means that signals will not be delayed, and the event loop
		2285	will not be interrupted regularly, which is more efficient (And good for
		2286	battery life on laptops).
		2287
		2288	This affects not just the pure-perl event loop, but also other event loops
		2289	that have no signal handling on their own (e.g. Glib, Tk, Qt).
		2290
		2291	Some event loops (POE, Event, Event::Lib) offer signal watchers natively,
		2292	and either employ their own workarounds (POE) or use AnyEvent's workaround
		2293	(using C<$AnyEvent::MAX_SIGNAL_LATENCY>). Installing L<Async::Interrupt>
		2294	does nothing for those backends.
		2295
		2296	=item L<EV>
		2297
		2298	This module isn't really "optional", as it is simply one of the backend
		2299	event loops that AnyEvent can use. However, it is simply the best event
		2300	loop available in terms of features, speed and stability: It supports
		2301	the AnyEvent API optimally, implements all the watcher types in XS, does
		2302	automatic timer adjustments even when no monotonic clock is available,
		2303	can take avdantage of advanced kernel interfaces such as C<epoll> and
		2304	C<kqueue>, and is the fastest backend I<by far>. You can even embed
		2305	L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>).
		2306
		2307	=item L<Guard>
		2308
		2309	The guard module, when used, will be used to implement
		2310	C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a
		2311	lot less memory), but otherwise doesn't affect guard operation much. It is
		2312	purely used for performance.
		2313
		2314	=item L<JSON> and L<JSON::XS>
		2315
		2316	This module is required when you want to read or write JSON data via
		2317	L<AnyEvent::Handle>. It is also written in pure-perl, but can take
		2318	advantage of the ulta-high-speed L<JSON::XS> module when it is installed.
		2319
		2320	In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is
		2321	installed.
		2322
		2323	=item L<Net::SSLeay>
		2324
		2325	Implementing TLS/SSL in Perl is certainly interesting, but not very
		2326	worthwhile: If this module is installed, then L<AnyEvent::Handle> (with
		2327	the help of L<AnyEvent::TLS>), gains the ability to do TLS/SSL.
		2328
		2329	=item L<Time::HiRes>
		2330
		2331	This module is part of perl since release 5.008. It will be used when the
		2332	chosen event library does not come with a timing source on it's own. The
		2333	pure-perl event loop (L<AnyEvent::Impl::Perl>) will additionally use it to
		2334	try to use a monotonic clock for timing stability.
		2335
		2336	=back
		2337
		2338
2052	=head1 FORK	2339	=head1 FORK
2053		2340
2054	Most event libraries are not fork-safe. The ones who are usually are	2341	Most event libraries are not fork-safe. The ones who are usually are
2055	because they rely on inefficient but fork-safe C<select> or C<poll>	2342	because they rely on inefficient but fork-safe C<select> or C<poll>
2056	calls. Only L<EV> is fully fork-aware.	2343	calls. Only L<EV> is fully fork-aware.
2057		2344
2058	If you have to fork, you must either do so I<before> creating your first	2345	If you have to fork, you must either do so I<before> creating your first
2059	watcher OR you must not use AnyEvent at all in the child.	2346	watcher OR you must not use AnyEvent at all in the child OR you must do
		2347	something completely out of the scope of AnyEvent.
2060		2348
2061		2349
2062	=head1 SECURITY CONSIDERATIONS	2350	=head1 SECURITY CONSIDERATIONS
2063		2351
2064	AnyEvent can be forced to load any event model via	2352	AnyEvent can be forced to load any event model via
…		…
2102	L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.	2390	L<Glib>, L<Tk>, L<Event::Lib>, L<Qt>, L<POE>.
2103		2391
2104	Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,	2392	Implementations: L<AnyEvent::Impl::EV>, L<AnyEvent::Impl::Event>,
2105	L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,	2393	L<AnyEvent::Impl::Glib>, L<AnyEvent::Impl::Tk>, L<AnyEvent::Impl::Perl>,
2106	L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,	2394	L<AnyEvent::Impl::EventLib>, L<AnyEvent::Impl::Qt>,
2107	L<AnyEvent::Impl::POE>.	2395	L<AnyEvent::Impl::POE>, L<AnyEvent::Impl::IOAsync>.
2108		2396
2109	Non-blocking file handles, sockets, TCP clients and	2397	Non-blocking file handles, sockets, TCP clients and
2110	servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>.	2398	servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.
2111		2399
2112	Asynchronous DNS: L<AnyEvent::DNS>.	2400	Asynchronous DNS: L<AnyEvent::DNS>.
2113		2401
2114	Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>,	2402	Coroutine support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>,
		2403	L<Coro::Event>,
2115		2404
2116	Nontrivial usage examples: L<Net::FCP>, L<Net::XMPP2>, L<AnyEvent::DNS>.	2405	Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::XMPP>,
		2406	L<AnyEvent::HTTP>.
2117		2407
2118		2408
2119	=head1 AUTHOR	2409	=head1 AUTHOR
2120		2410
2121	Marc Lehmann <schmorp@schmorp.de>	2411	Marc Lehmann <schmorp@schmorp.de>

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Comparing AnyEvent/lib/AnyEvent.pm (file contents): Revision 1.224 by root, Fri Jul 3 21:44:14 2009 UTC vs. Revision 1.247 by root, Sat Jul 18 22:24:17 2009 UTC

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Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.224 by root, Fri Jul 3 21:44:14 2009 UTC vs.
Revision 1.247 by root, Sat Jul 18 22:24:17 2009 UTC