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

Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.179 by root, Thu Sep 4 10:58:58 2008 UTC vs.
Revision 1.182 by root, Sun Sep 7 15:27:17 2008 UTC

…		…
340	=head2 CHILD PROCESS WATCHERS	340	=head2 CHILD PROCESS WATCHERS
341		341
342	You can also watch on a child process exit and catch its exit status.	342	You can also watch on a child process exit and catch its exit status.
343		343
344	The child process is specified by the C<pid> argument (if set to C<0>, it	344	The child process is specified by the C<pid> argument (if set to C<0>, it
345	watches for any child process exit). The watcher will trigger as often	345	watches for any child process exit). The watcher will triggered only when
346	as status change for the child are received. This works by installing a	346	the child process has finished and an exit status is available, not on
347	signal handler for C<SIGCHLD>. The callback will be called with the pid	347	any trace events (stopped/continued).
348	and exit status (as returned by waitpid), so unlike other watcher types,	348
349	you I<can> rely on child watcher callback arguments.	349	The callback will be called with the pid and exit status (as returned by
		350	waitpid), so unlike other watcher types, you I<can> rely on child watcher
		351	callback arguments.
		352
		353	This watcher type works by installing a signal handler for C<SIGCHLD>,
		354	and since it cannot be shared, nothing else should use SIGCHLD or reap
		355	random child processes (waiting for specific child processes, e.g. inside
		356	C<system>, is just fine).
350		357
351	There is a slight catch to child watchers, however: you usually start them	358	There is a slight catch to child watchers, however: you usually start them
352	I<after> the child process was created, and this means the process could	359	I<after> the child process was created, and this means the process could
353	have exited already (and no SIGCHLD will be sent anymore).	360	have exited already (and no SIGCHLD will be sent anymore).
354		361
…		…
850	=cut	857	=cut
851		858
852	package AnyEvent;	859	package AnyEvent;
853		860
854	no warnings;	861	no warnings;
855	use strict;	862	use strict qw(vars subs);
856		863
857	use Carp;	864	use Carp;
858		865
859	our $VERSION = 4.233;	866	our $VERSION = 4.234;
860	our $MODEL;	867	our $MODEL;
861		868
862	our $AUTOLOAD;	869	our $AUTOLOAD;
863	our @ISA;	870	our @ISA;
864		871
…		…
1021	BEGIN {	1028	BEGIN {
1022	if (eval "use Time::HiRes (); time (); 1") {	1029	if (eval "use Time::HiRes (); time (); 1") {
1023	*_time = \&Time::HiRes::time;	1030	*_time = \&Time::HiRes::time;
1024	# if (eval "use POSIX (); (POSIX::times())...	1031	# if (eval "use POSIX (); (POSIX::times())...
1025	} else {	1032	} else {
1026	*_time = \&CORE::time; # epic fail	1033	*_time = sub { time }; # epic fail
1027	}	1034	}
1028	}	1035	}
1029		1036
1030	sub time { _time }	1037	sub time { _time }
1031	sub now { _time }	1038	sub now { _time }
…		…
1175		1182
1176	# undocumented/compatibility with pre-3.4	1183	# undocumented/compatibility with pre-3.4
1177	*broadcast = \&send;	1184	*broadcast = \&send;
1178	*wait = \&_wait;	1185	*wait = \&_wait;
1179		1186
		1187	=head1 ERROR AND EXCEPTION HANDLING
		1188
		1189	In general, AnyEvent does not do any error handling - it relies on the
		1190	caller to do that if required. The L<AnyEvent::Strict> module (see also
		1191	the C<PERL_ANYEVENT_STRICT> environment variable, below) provides strict
		1192	checking of all AnyEvent methods, however, which is highly useful during
		1193	development.
		1194
		1195	As for exception handling (i.e. runtime errors and exceptions thrown while
		1196	executing a callback), this is not only highly event-loop specific, but
		1197	also not in any way wrapped by this module, as this is the job of the main
		1198	program.
		1199
		1200	The pure perl event loop simply re-throws the exception (usually
		1201	within C<< condvar->recv >>), the L<Event> and L<EV> modules call C<<
		1202	$Event/EV::DIED->() >>, L<Glib> uses C<< install_exception_handler >> and
		1203	so on.
		1204
		1205	=head1 ENVIRONMENT VARIABLES
		1206
		1207	The following environment variables are used by this module or its
		1208	submodules:
		1209
		1210	=over 4
		1211
		1212	=item C<PERL_ANYEVENT_VERBOSE>
		1213
		1214	By default, AnyEvent will be completely silent except in fatal
		1215	conditions. You can set this environment variable to make AnyEvent more
		1216	talkative.
		1217
		1218	When set to C<1> or higher, causes AnyEvent to warn about unexpected
		1219	conditions, such as not being able to load the event model specified by
		1220	C<PERL_ANYEVENT_MODEL>.
		1221
		1222	When set to C<2> or higher, cause AnyEvent to report to STDERR which event
		1223	model it chooses.
		1224
		1225	=item C<PERL_ANYEVENT_STRICT>
		1226
		1227	AnyEvent does not do much argument checking by default, as thorough
		1228	argument checking is very costly. Setting this variable to a true value
		1229	will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly
		1230	check the arguments passed to most method calls. If it finds any problems
		1231	it will croak.
		1232
		1233	In other words, enables "strict" mode.
		1234
		1235	Unlike C<use strict>, it is definitely recommended ot keep it off in
		1236	production. Keeping C<PERL_ANYEVENT_STRICT=1> in your environment while
		1237	developing programs can be very useful, however.
		1238
		1239	=item C<PERL_ANYEVENT_MODEL>
		1240
		1241	This can be used to specify the event model to be used by AnyEvent, before
		1242	auto detection and -probing kicks in. It must be a string consisting
		1243	entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended
		1244	and the resulting module name is loaded and if the load was successful,
		1245	used as event model. If it fails to load AnyEvent will proceed with
		1246	auto detection and -probing.
		1247
		1248	This functionality might change in future versions.
		1249
		1250	For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you
		1251	could start your program like this:
		1252
		1253	PERL_ANYEVENT_MODEL=Perl perl ...
		1254
		1255	=item C<PERL_ANYEVENT_PROTOCOLS>
		1256
		1257	Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences
		1258	for IPv4 or IPv6. The default is unspecified (and might change, or be the result
		1259	of auto probing).
		1260
		1261	Must be set to a comma-separated list of protocols or address families,
		1262	current supported: C<ipv4> and C<ipv6>. Only protocols mentioned will be
		1263	used, and preference will be given to protocols mentioned earlier in the
		1264	list.
		1265
		1266	This variable can effectively be used for denial-of-service attacks
		1267	against local programs (e.g. when setuid), although the impact is likely
		1268	small, as the program has to handle connection errors already-
		1269
		1270	Examples: C<PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6> - prefer IPv4 over IPv6,
		1271	but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4>
		1272	- only support IPv4, never try to resolve or contact IPv6
		1273	addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or
		1274	IPv6, but prefer IPv6 over IPv4.
		1275
		1276	=item C<PERL_ANYEVENT_EDNS0>
		1277
		1278	Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension
		1279	for DNS. This extension is generally useful to reduce DNS traffic, but
		1280	some (broken) firewalls drop such DNS packets, which is why it is off by
		1281	default.
		1282
		1283	Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce
		1284	EDNS0 in its DNS requests.
		1285
		1286	=item C<PERL_ANYEVENT_MAX_FORKS>
		1287
		1288	The maximum number of child processes that C<AnyEvent::Util::fork_call>
		1289	will create in parallel.
		1290
		1291	=back
		1292
1180	=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE	1293	=head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE
1181		1294
1182	This is an advanced topic that you do not normally need to use AnyEvent in	1295	This is an advanced topic that you do not normally need to use AnyEvent in
1183	a module. This section is only of use to event loop authors who want to	1296	a module. This section is only of use to event loop authors who want to
1184	provide AnyEvent compatibility.	1297	provide AnyEvent compatibility.
…		…
1217		1330
1218	I<rxvt-unicode> also cheats a bit by not providing blocking access to	1331	I<rxvt-unicode> also cheats a bit by not providing blocking access to
1219	condition variables: code blocking while waiting for a condition will	1332	condition variables: code blocking while waiting for a condition will
1220	C<die>. This still works with most modules/usages, and blocking calls must	1333	C<die>. This still works with most modules/usages, and blocking calls must
1221	not be done in an interactive application, so it makes sense.	1334	not be done in an interactive application, so it makes sense.
1222
1223	=head1 ENVIRONMENT VARIABLES
1224
1225	The following environment variables are used by this module:
1226
1227	=over 4
1228
1229	=item C<PERL_ANYEVENT_VERBOSE>
1230
1231	By default, AnyEvent will be completely silent except in fatal
1232	conditions. You can set this environment variable to make AnyEvent more
1233	talkative.
1234
1235	When set to C<1> or higher, causes AnyEvent to warn about unexpected
1236	conditions, such as not being able to load the event model specified by
1237	C<PERL_ANYEVENT_MODEL>.
1238
1239	When set to C<2> or higher, cause AnyEvent to report to STDERR which event
1240	model it chooses.
1241
1242	=item C<PERL_ANYEVENT_STRICT>
1243
1244	AnyEvent does not do much argument checking by default, as thorough
1245	argument checking is very costly. Setting this variable to a true value
1246	will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly
1247	check the arguments passed to most method calls. If it finds any problems
1248	it will croak.
1249
1250	In other words, enables "strict" mode.
1251
1252	Unlike C<use strict> it is definitely recommended ot keep it off in
1253	production.
1254
1255	=item C<PERL_ANYEVENT_MODEL>
1256
1257	This can be used to specify the event model to be used by AnyEvent, before
1258	auto detection and -probing kicks in. It must be a string consisting
1259	entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended
1260	and the resulting module name is loaded and if the load was successful,
1261	used as event model. If it fails to load AnyEvent will proceed with
1262	auto detection and -probing.
1263
1264	This functionality might change in future versions.
1265
1266	For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you
1267	could start your program like this:
1268
1269	PERL_ANYEVENT_MODEL=Perl perl ...
1270
1271	=item C<PERL_ANYEVENT_PROTOCOLS>
1272
1273	Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences
1274	for IPv4 or IPv6. The default is unspecified (and might change, or be the result
1275	of auto probing).
1276
1277	Must be set to a comma-separated list of protocols or address families,
1278	current supported: C<ipv4> and C<ipv6>. Only protocols mentioned will be
1279	used, and preference will be given to protocols mentioned earlier in the
1280	list.
1281
1282	This variable can effectively be used for denial-of-service attacks
1283	against local programs (e.g. when setuid), although the impact is likely
1284	small, as the program has to handle connection errors already-
1285
1286	Examples: C<PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6> - prefer IPv4 over IPv6,
1287	but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4>
1288	- only support IPv4, never try to resolve or contact IPv6
1289	addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or
1290	IPv6, but prefer IPv6 over IPv4.
1291
1292	=item C<PERL_ANYEVENT_EDNS0>
1293
1294	Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension
1295	for DNS. This extension is generally useful to reduce DNS traffic, but
1296	some (broken) firewalls drop such DNS packets, which is why it is off by
1297	default.
1298
1299	Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce
1300	EDNS0 in its DNS requests.
1301
1302	=item C<PERL_ANYEVENT_MAX_FORKS>
1303
1304	The maximum number of child processes that C<AnyEvent::Util::fork_call>
1305	will create in parallel.
1306
1307	=back
1308		1335
1309	=head1 EXAMPLE PROGRAM	1336	=head1 EXAMPLE PROGRAM
1310		1337
1311	The following program uses an I/O watcher to read data from STDIN, a timer	1338	The following program uses an I/O watcher to read data from STDIN, a timer
1312	to display a message once per second, and a condition variable to quit the	1339	to display a message once per second, and a condition variable to quit the

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Comparing AnyEvent/lib/AnyEvent.pm (file contents): Revision 1.179 by root, Thu Sep 4 10:58:58 2008 UTC vs. Revision 1.182 by root, Sun Sep 7 15:27:17 2008 UTC

Diff Legend

Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.179 by root, Thu Sep 4 10:58:58 2008 UTC vs.
Revision 1.182 by root, Sun Sep 7 15:27:17 2008 UTC