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

Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.164 by root, Tue Jul 8 19:50:25 2008 UTC vs.
Revision 1.171 by root, Wed Jul 16 21:17:59 2008 UTC

…		…
33		33
34	Executive Summary: AnyEvent is I<compatible>, AnyEvent is I<free of	34	Executive Summary: AnyEvent is I<compatible>, AnyEvent is I<free of
35	policy> and AnyEvent is I<small and efficient>.	35	policy> and AnyEvent is I<small and efficient>.
36		36
37	First and foremost, I<AnyEvent is not an event model> itself, it only	37	First and foremost, I<AnyEvent is not an event model> itself, it only
38	interfaces to whatever event model the main program happens to use in a	38	interfaces to whatever event model the main program happens to use, in a
39	pragmatic way. For event models and certain classes of immortals alike,	39	pragmatic way. For event models and certain classes of immortals alike,
40	the statement "there can only be one" is a bitter reality: In general,	40	the statement "there can only be one" is a bitter reality: In general,
41	only one event loop can be active at the same time in a process. AnyEvent	41	only one event loop can be active at the same time in a process. AnyEvent
42	helps hiding the differences between those event loops.	42	cannot change this, but it can hide the differences between those event
		43	loops.
43		44
44	The goal of AnyEvent is to offer module authors the ability to do event	45	The goal of AnyEvent is to offer module authors the ability to do event
45	programming (waiting for I/O or timer events) without subscribing to a	46	programming (waiting for I/O or timer events) without subscribing to a
46	religion, a way of living, and most importantly: without forcing your	47	religion, a way of living, and most importantly: without forcing your
47	module users into the same thing by forcing them to use the same event	48	module users into the same thing by forcing them to use the same event
48	model you use.	49	model you use.
49		50
50	For modules like POE or IO::Async (which is a total misnomer as it is	51	For modules like POE or IO::Async (which is a total misnomer as it is
51	actually doing all I/O I<synchronously>...), using them in your module is	52	actually doing all I/O I<synchronously>...), using them in your module is
52	like joining a cult: After you joined, you are dependent on them and you	53	like joining a cult: After you joined, you are dependent on them and you
53	cannot use anything else, as it is simply incompatible to everything that	54	cannot use anything else, as they are simply incompatible to everything
54	isn't itself. What's worse, all the potential users of your module are	55	that isn't them. What's worse, all the potential users of your
55	I<also> forced to use the same event loop you use.	56	module are I<also> forced to use the same event loop you use.
56		57
57	AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works	58	AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works
58	fine. AnyEvent + Tk works fine etc. etc. but none of these work together	59	fine. AnyEvent + Tk works fine etc. etc. but none of these work together
59	with the rest: POE + IO::Async? No go. Tk + Event? No go. Again: if	60	with the rest: POE + IO::Async? No go. Tk + Event? No go. Again: if
60	your module uses one of those, every user of your module has to use it,	61	your module uses one of those, every user of your module has to use it,
61	too. But if your module uses AnyEvent, it works transparently with all	62	too. But if your module uses AnyEvent, it works transparently with all
62	event models it supports (including stuff like POE and IO::Async, as long	63	event models it supports (including stuff like IO::Async, as long as those
63	as those use one of the supported event loops. It is trivial to add new	64	use one of the supported event loops. It is trivial to add new event loops
64	event loops to AnyEvent, too, so it is future-proof).	65	to AnyEvent, too, so it is future-proof).
65		66
66	In addition to being free of having to use I<the one and only true event	67	In addition to being free of having to use I<the one and only true event
67	model>, AnyEvent also is free of bloat and policy: with POE or similar	68	model>, AnyEvent also is free of bloat and policy: with POE or similar
68	modules, you get an enormous amount of code and strict rules you have to	69	modules, you get an enormous amount of code and strict rules you have to
69	follow. AnyEvent, on the other hand, is lean and up to the point, by only	70	follow. AnyEvent, on the other hand, is lean and up to the point, by only
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152	=head2 I/O WATCHERS	153	=head2 I/O WATCHERS
153		154
154	You can create an I/O watcher by calling the C<< AnyEvent->io >> method	155	You can create an I/O watcher by calling the C<< AnyEvent->io >> method
155	with the following mandatory key-value pairs as arguments:	156	with the following mandatory key-value pairs as arguments:
156		157
157	C<fh> the Perl I<file handle> (I<not> file descriptor) to watch	158	C<fh> the Perl I<file handle> (I<not> file descriptor) to watch for events
158	for events. C<poll> must be a string that is either C<r> or C<w>,	159	(AnyEvent might or might not keep a reference to this file handle). C<poll>
159	which creates a watcher waiting for "r"eadable or "w"ritable events,	160	must be a string that is either C<r> or C<w>, which creates a watcher
160	respectively. C<cb> is the callback to invoke each time the file handle	161	waiting for "r"eadable or "w"ritable events, respectively. C<cb> is the
161	becomes ready.	162	callback to invoke each time the file handle becomes ready.
162		163
163	Although the callback might get passed parameters, their value and	164	Although the callback might get passed parameters, their value and
164	presence is undefined and you cannot rely on them. Portable AnyEvent	165	presence is undefined and you cannot rely on them. Portable AnyEvent
165	callbacks cannot use arguments passed to I/O watcher callbacks.	166	callbacks cannot use arguments passed to I/O watcher callbacks.
166		167
…		…
193	Although the callback might get passed parameters, their value and	194	Although the callback might get passed parameters, their value and
194	presence is undefined and you cannot rely on them. Portable AnyEvent	195	presence is undefined and you cannot rely on them. Portable AnyEvent
195	callbacks cannot use arguments passed to time watcher callbacks.	196	callbacks cannot use arguments passed to time watcher callbacks.
196		197
197	The callback will normally be invoked once only. If you specify another	198	The callback will normally be invoked once only. If you specify another
198	parameter, C<interval>, as a positive number, then the callback will be	199	parameter, C<interval>, as a strictly positive number (> 0), then the
199	invoked regularly at that interval (in fractional seconds) after the first	200	callback will be invoked regularly at that interval (in fractional
200	invocation.	201	seconds) after the first invocation. If C<interval> is specified with a
		202	false value, then it is treated as if it were missing.
201		203
202	The callback will be rescheduled before invoking the callback, but no	204	The callback will be rescheduled before invoking the callback, but no
203	attempt is done to avoid timer drift in most backends, so the interval is	205	attempt is done to avoid timer drift in most backends, so the interval is
204	only approximate.	206	only approximate.
205		207
…		…
302	=back	304	=back
303		305
304	=head2 SIGNAL WATCHERS	306	=head2 SIGNAL WATCHERS
305		307
306	You can watch for signals using a signal watcher, C<signal> is the signal	308	You can watch for signals using a signal watcher, C<signal> is the signal
307	I<name> without any C<SIG> prefix, C<cb> is the Perl callback to	309	I<name> in uppercase and without any C<SIG> prefix, C<cb> is the Perl
308	be invoked whenever a signal occurs.	310	callback to be invoked whenever a signal occurs.
309		311
310	Although the callback might get passed parameters, their value and	312	Although the callback might get passed parameters, their value and
311	presence is undefined and you cannot rely on them. Portable AnyEvent	313	presence is undefined and you cannot rely on them. Portable AnyEvent
312	callbacks cannot use arguments passed to signal watcher callbacks.	314	callbacks cannot use arguments passed to signal watcher callbacks.
313		315
…		…
824	no warnings;	826	no warnings;
825	use strict;	827	use strict;
826		828
827	use Carp;	829	use Carp;
828		830
829	our $VERSION = 4.2;	831	our $VERSION = 4.21;
830	our $MODEL;	832	our $MODEL;
831		833
832	our $AUTOLOAD;	834	our $AUTOLOAD;
833	our @ISA;	835	our @ISA;
834		836
…		…
937	$MODEL	939	$MODEL
938	or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.";	940	or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.";
939	}	941	}
940	}	942	}
941		943
		944	push @{"$MODEL\::ISA"}, "AnyEvent::Base";
		945
942	unshift @ISA, $MODEL;	946	unshift @ISA, $MODEL;
943	push @{"$MODEL\::ISA"}, "AnyEvent::Base";	947
		948	require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT};
944		949
945	(shift @post_detect)->() while @post_detect;	950	(shift @post_detect)->() while @post_detect;
946	}	951	}
947		952
948	$MODEL	953	$MODEL
…		…
956		961
957	detect unless $MODEL;	962	detect unless $MODEL;
958		963
959	my $class = shift;	964	my $class = shift;
960	$class->$func (@_);	965	$class->$func (@_);
		966	}
		967
		968	# utility function to dup a filehandle. this is used by many backends
		969	# to support binding more than one watcher per filehandle (they usually
		970	# allow only one watcher per fd, so we dup it to get a different one).
		971	sub _dupfh($$$$) {
		972	my ($poll, $fh, $r, $w) = @_;
		973
		974	require Fcntl;
		975
		976	# cygwin requires the fh mode to be matching, unix doesn't
		977	my ($rw, $mode) = $poll eq "r" ? ($r, "<")
		978	: $poll eq "w" ? ($w, ">")
		979	: Carp::croak "AnyEvent->io requires poll set to either 'r' or 'w'";
		980
		981	open my $fh2, "$mode&" . fileno $fh
		982	or die "cannot dup() filehandle: $!";
		983
		984	# we assume CLOEXEC is already set by perl in all important cases
		985
		986	($fh2, $rw)
961	}	987	}
962		988
963	package AnyEvent::Base;	989	package AnyEvent::Base;
964		990
965	# default implementation for now and time	991	# default implementation for now and time
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1175	conditions, such as not being able to load the event model specified by	1201	conditions, such as not being able to load the event model specified by
1176	C<PERL_ANYEVENT_MODEL>.	1202	C<PERL_ANYEVENT_MODEL>.
1177		1203
1178	When set to C<2> or higher, cause AnyEvent to report to STDERR which event	1204	When set to C<2> or higher, cause AnyEvent to report to STDERR which event
1179	model it chooses.	1205	model it chooses.
		1206
		1207	=item C<PERL_ANYEVENT_STRICT>
		1208
		1209	AnyEvent does not do much argument checking by default, as thorough
		1210	argument checking is very costly. Setting this variable to a true value
		1211	will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly
		1212	check the arguments passed to most method calls. If it finds any problems
		1213	it will croak.
		1214
		1215	In other words, enables "strict" mode.
		1216
		1217	Unlike C<use strict> it is definitely recommended ot keep it off in
		1218	production.
1180		1219
1181	=item C<PERL_ANYEVENT_MODEL>	1220	=item C<PERL_ANYEVENT_MODEL>
1182		1221
1183	This can be used to specify the event model to be used by AnyEvent, before	1222	This can be used to specify the event model to be used by AnyEvent, before
1184	auto detection and -probing kicks in. It must be a string consisting	1223	auto detection and -probing kicks in. It must be a string consisting
…		…
1681		1720
1682	use AnyEvent;	1721	use AnyEvent;
1683		1722
1684	Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can	1723	Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can
1685	be used to probe what backend is used and gain other information (which is	1724	be used to probe what backend is used and gain other information (which is
1686	probably even less useful to an attacker than PERL_ANYEVENT_MODEL).	1725	probably even less useful to an attacker than PERL_ANYEVENT_MODEL), and
		1726	$ENV{PERL_ANYEGENT_STRICT}.
1687		1727
1688		1728
1689	=head1 BUGS	1729	=head1 BUGS
1690		1730
1691	Perl 5.8 has numerous memleaks that sometimes hit this module and are hard	1731	Perl 5.8 has numerous memleaks that sometimes hit this module and are hard

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Comparing AnyEvent/lib/AnyEvent.pm (file contents): Revision 1.164 by root, Tue Jul 8 19:50:25 2008 UTC vs. Revision 1.171 by root, Wed Jul 16 21:17:59 2008 UTC

Diff Legend

Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.164 by root, Tue Jul 8 19:50:25 2008 UTC vs.
Revision 1.171 by root, Wed Jul 16 21:17:59 2008 UTC