ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/AnyEvent/lib/AnyEvent.pm
(Generate patch)

Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.384 by root, Mon Sep 5 07:21:54 2011 UTC vs.
Revision 1.408 by root, Thu Dec 6 12:04:23 2012 UTC

… …
415not restart syscalls (that includes L<Async::Interrupt> and AnyEvent's 415not restart syscalls (that includes L<Async::Interrupt> and AnyEvent's
416pure perl implementation). 416pure perl implementation).
417 417
418=head3 Safe/Unsafe Signals 418=head3 Safe/Unsafe Signals
419 419
420Perl signals can be either "safe" (synchronous to opcode handling) or 420Perl signals can be either "safe" (synchronous to opcode handling)
421"unsafe" (asynchronous) - the former might get delayed indefinitely, the 421or "unsafe" (asynchronous) - the former might delay signal delivery
422latter might corrupt your memory. 422indefinitely, the latter might corrupt your memory.
423 423
424AnyEvent signal handlers are, in addition, synchronous to the event loop, 424AnyEvent signal handlers are, in addition, synchronous to the event loop,
425i.e. they will not interrupt your running perl program but will only be 425i.e. they will not interrupt your running perl program but will only be
426called as part of the normal event handling (just like timer, I/O etc. 426called as part of the normal event handling (just like timer, I/O etc.
427callbacks, too). 427callbacks, too).
428 428
429=head3 Signal Races, Delays and Workarounds 429=head3 Signal Races, Delays and Workarounds
430 430
431Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching 431Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support
432callbacks to signals in a generic way, which is a pity, as you cannot 432attaching callbacks to signals in a generic way, which is a pity,
433do race-free signal handling in perl, requiring C libraries for 433as you cannot do race-free signal handling in perl, requiring
434this. AnyEvent will try to do its best, which means in some cases, 434C libraries for this. AnyEvent will try to do its best, which
435signals will be delayed. The maximum time a signal might be delayed is 435means in some cases, signals will be delayed. The maximum time
436specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This 436a signal might be delayed is 10 seconds by default, but can
437variable can be changed only before the first signal watcher is created, 437be overriden via C<$ENV{PERL_ANYEVENT_MAX_SIGNAL_LATENCY}> or
438and should be left alone otherwise. This variable determines how often 438C<$AnyEvent::MAX_SIGNAL_LATENCY> - see the L<ENVIRONMENT VARIABLES>
439AnyEvent polls for signals (in case a wake-up was missed). Higher values 439section for details.
440will cause fewer spurious wake-ups, which is better for power and CPU
441saving.
442 440
443All these problems can be avoided by installing the optional 441All these problems can be avoided by installing the optional
444L<Async::Interrupt> module, which works with most event loops. It will not 442L<Async::Interrupt> module, which works with most event loops. It will not
445work with inherently broken event loops such as L<Event> or L<Event::Lib> 443work 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
447one-second latency). For those, you just have to suffer the delays. 445delays.
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
… …
765 }; 763 };
766 } 764 }
767 765
768 $cv->end; 766 $cv->end;
769 767
768 ...
769
770 my $results = $cv->recv;
771
770This code fragment supposedly pings a number of hosts and calls 772This code fragment supposedly pings a number of hosts and calls
771C<send> after results for all then have have been gathered - in any 773C<send> after results for all then have have been gathered - in any
772order. To achieve this, the code issues a call to C<begin> when it starts 774order. To achieve this, the code issues a call to C<begin> when it starts
773each ping request and calls C<end> when it has received some result for 775each ping request and calls C<end> when it has received some result for
774it. Since C<begin> and C<end> only maintain a counter, the order in which 776it. Since C<begin> and C<end> only maintain a counter, the order in which
… …
1225 1227
1226package AnyEvent; 1228package AnyEvent;
1227 1229
1228# basically a tuned-down version of common::sense 1230# basically a tuned-down version of common::sense
1229sub common_sense { 1231sub common_sense {
1230 # from common:.sense 3.4 1232 # from common:.sense 3.5
1233 local $^W;
1231 ${^WARNING_BITS} ^= ${^WARNING_BITS} ^ "\x3c\x3f\x33\x00\x0f\xf0\x0f\xc0\xf0\xfc\x33\x00"; 1234 ${^WARNING_BITS} ^= ${^WARNING_BITS} ^ "\x3c\x3f\x33\x00\x0f\xf0\x0f\xc0\xf0\xfc\x33\x00";
1232 # use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl) 1235 # use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl)
1233 $^H |= 0x00000600; 1236 $^H |= 0x00000600;
1234} 1237}
1235 1238
1236BEGIN { AnyEvent::common_sense } 1239BEGIN { AnyEvent::common_sense }
1237 1240
1238use Carp (); 1241use Carp ();
1239 1242
1240our $VERSION = '6.02'; 1243our $VERSION = '7.04';
1241our $MODEL; 1244our $MODEL;
1242our @ISA; 1245our @ISA;
1243our @REGISTRY; 1246our @REGISTRY;
1244our $VERBOSE; 1247our $VERBOSE;
1245our $MAX_SIGNAL_LATENCY = 10;
1246our %PROTOCOL; # (ipv4|ipv6) => (1|2), higher numbers are preferred 1248our %PROTOCOL; # (ipv4|ipv6) => (1|2), higher numbers are preferred
1249our $MAX_SIGNAL_LATENCY = $ENV{PERL_ANYEVENT_MAX_SIGNAL_LATENCY} || 10; # executes after the BEGIN block below (tainting!)
1247 1250
1248BEGIN { 1251BEGIN {
1249 require "AnyEvent/constants.pl"; 1252 require "AnyEvent/constants.pl";
1250 1253
1251 eval "sub TAINT (){" . (${^TAINT}*1) . "}"; 1254 eval "sub TAINT (){" . (${^TAINT}*1) . "}";
… …
1304} 1307}
1305 1308
1306sub log($$;@) { 1309sub log($$;@) {
1307 # only load the big bloated module when we actually are about to log something 1310 # only load the big bloated module when we actually are about to log something
1308 if ($_[0] <= ($VERBOSE || 1)) { # also catches non-numeric levels(!) and fatal 1311 if ($_[0] <= ($VERBOSE || 1)) { # also catches non-numeric levels(!) and fatal
1312 local ($!, $@);
1309 require AnyEvent::Log; # among other things, sets $VERBOSE to 9 1313 require AnyEvent::Log; # among other things, sets $VERBOSE to 9
1310 # AnyEvent::Log overwrites this function 1314 # AnyEvent::Log overwrites this function
1311 goto &log; 1315 goto &log;
1312 } 1316 }
1313 1317
1314 0 # not logged 1318 0 # not logged
1315} 1319}
1316 1320
1317sub logger($;$) { 1321sub _logger($;$) {
1318 package AnyEvent::Log;
1319
1320 my ($level, $renabled) = @_; 1322 my ($level, $renabled) = @_;
1321 1323
1322 $$renabled = $level <= $VERBOSE; 1324 $$renabled = $level <= $VERBOSE;
1323 1325
1324 my $pkg = (caller)[0];
1325
1326 my $logger = [$pkg, $level, $renabled]; 1326 my $logger = [(caller)[0], $level, $renabled];
1327 1327
1328 our %LOGGER;
1329 $LOGGER{$logger+0} = $logger; 1328 $AnyEvent::Log::LOGGER{$logger+0} = $logger;
1330 1329
1330# return unless defined wantarray;
1331#
1331 require AnyEvent::Util; 1332# require AnyEvent::Util;
1332 my $guard = AnyEvent::Util::guard (sub { 1333# my $guard = AnyEvent::Util::guard (sub {
1333 # "clean up" 1334# # "clean up"
1334 delete $LOGGER{$logger+0}; 1335# delete $LOGGER{$logger+0};
1335 }); 1336# });
1336 1337#
1337 sub { 1338# sub {
1338 return 0 unless $$renabled; 1339# return 0 unless $$renabled;
1339 1340#
1340 $guard if 0; # keep guard alive, but don't cause runtime overhead 1341# $guard if 0; # keep guard alive, but don't cause runtime overhead
1341 require AnyEvent::Log unless $AnyEvent::Log::VERSION; 1342# require AnyEvent::Log unless $AnyEvent::Log::VERSION;
1342 package AnyEvent::Log; 1343# package AnyEvent::Log;
1343 _log ($logger->[0], $level, @_) # logger->[0] has been converted at load time 1344# _log ($logger->[0], $level, @_) # logger->[0] has been converted at load time
1344 } 1345# }
1345} 1346}
1346 1347
1347if (length $ENV{PERL_ANYEVENT_LOG}) { 1348if (length $ENV{PERL_ANYEVENT_LOG}) {
1348 require AnyEvent::Log; # AnyEvent::Log does the thing for us 1349 require AnyEvent::Log; # AnyEvent::Log does the thing for us
1349} 1350}
1350 1351
1351our @models = ( 1352our @models = (
1352 [EV:: => AnyEvent::Impl::EV:: , 1], 1353 [EV:: => AnyEvent::Impl::EV::],
1353 [AnyEvent::Loop:: => AnyEvent::Impl::Perl:: , 1], 1354 [AnyEvent::Loop:: => AnyEvent::Impl::Perl::],
1354 # everything below here will not (normally) be autoprobed 1355 # everything below here will not (normally) be autoprobed
1355 # as the pure perl backend should work everywhere 1356 # as the pure perl backend should work everywhere
1356 # and is usually faster 1357 # and is usually faster
1358 [Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package, so msut be near the top
1357 [Event:: => AnyEvent::Impl::Event::, 1], 1359 [Event:: => AnyEvent::Impl::Event::], # slow, stable
1358 [Glib:: => AnyEvent::Impl::Glib:: , 1], # becomes extremely slow with many watchers 1360 [Glib:: => AnyEvent::Impl::Glib::], # becomes extremely slow with many watchers
1361 # everything below here should not be autoloaded
1359 [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy 1362 [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy
1360 [Irssi:: => AnyEvent::Impl::Irssi::], # Irssi has a bogus "Event" package
1361 [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles 1363 [Tk:: => AnyEvent::Impl::Tk::], # crashes with many handles
1362 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program 1364 [Qt:: => AnyEvent::Impl::Qt::], # requires special main program
1363 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza 1365 [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza
1364 [Wx:: => AnyEvent::Impl::POE::], 1366 [Wx:: => AnyEvent::Impl::POE::],
1365 [Prima:: => AnyEvent::Impl::POE::], 1367 [Prima:: => AnyEvent::Impl::POE::],
… …
1394our @methods = qw(io timer time now now_update signal child idle condvar); 1396our @methods = qw(io timer time now now_update signal child idle condvar);
1395 1397
1396sub detect() { 1398sub detect() {
1397 return $MODEL if $MODEL; # some programs keep references to detect 1399 return $MODEL if $MODEL; # some programs keep references to detect
1398 1400
1401 # IO::Async::Loop::AnyEvent is extremely evil, refuse to work with it
1402 # the author knows about the problems and what it does to AnyEvent as a whole
1403 # (and the ability of others to use AnyEvent), but simply wants to abuse AnyEvent
1404 # anyway.
1405 AnyEvent::log fatal => "IO::Async::Loop::AnyEvent detected - that module is broken by\n"
1406 . "design, abuses internals and breaks AnyEvent - will not continue."
1407 if exists $INC{"IO/Async/Loop/AnyEvent.pm"};
1408
1399 local $!; # for good measure 1409 local $!; # for good measure
1400 local $SIG{__DIE__}; # we use eval 1410 local $SIG{__DIE__}; # we use eval
1401 1411
1402 # free some memory 1412 # free some memory
1403 *detect = sub () { $MODEL }; 1413 *detect = sub () { $MODEL };
… …
1411 1421
1412 if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z0-9:]+)$/) { 1422 if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z0-9:]+)$/) {
1413 my $model = $1; 1423 my $model = $1;
1414 $model = "AnyEvent::Impl::$model" unless $model =~ s/::$//; 1424 $model = "AnyEvent::Impl::$model" unless $model =~ s/::$//;
1415 if (eval "require $model") { 1425 if (eval "require $model") {
1416 AnyEvent::log 7 => "loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it."; 1426 AnyEvent::log 7 => "Loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.";
1417 $MODEL = $model; 1427 $MODEL = $model;
1418 } else { 1428 } else {
1419 AnyEvent::log 4 => "unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@"; 1429 AnyEvent::log 4 => "Unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@";
1420 } 1430 }
1421 } 1431 }
1422 1432
1423 # check for already loaded models 1433 # check for already loaded models
1424 unless ($MODEL) { 1434 unless ($MODEL) {
1425 for (@REGISTRY, @models) { 1435 for (@REGISTRY, @models) {
1426 my ($package, $model) = @$_; 1436 my ($package, $model) = @$_;
1427 if (${"$package\::VERSION"} > 0) { 1437 if (${"$package\::VERSION"} > 0) {
1428 if (eval "require $model") { 1438 if (eval "require $model") {
1429 AnyEvent::log 7 => "autodetected model '$model', using it."; 1439 AnyEvent::log 7 => "Autodetected model '$model', using it.";
1440 $MODEL = $model;
1441 last;
1442 } else {
1443 AnyEvent::log 8 => "Detected event loop $package, but cannot load '$model', skipping: $@";
1444 }
1445 }
1446 }
1447
1448 unless ($MODEL) {
1449 # try to autoload a model
1450 for (@REGISTRY, @models) {
1451 my ($package, $model) = @$_;
1452 if (
1453 eval "require $package"
1454 and ${"$package\::VERSION"} > 0
1455 and eval "require $model"
1456 ) {
1457 AnyEvent::log 7 => "Autoloaded model '$model', using it.";
1430 $MODEL = $model; 1458 $MODEL = $model;
1431 last; 1459 last;
1432 } 1460 }
1433 } 1461 }
1434 }
1435
1436 unless ($MODEL) {
1437 # try to autoload a model
1438 for (@REGISTRY, @models) {
1439 my ($package, $model, $autoload) = @$_;
1440 if (
1441 $autoload
1442 and eval "require $package"
1443 and ${"$package\::VERSION"} > 0
1444 and eval "require $model"
1445 ) {
1446 AnyEvent::log 7 => "autoloaded model '$model', using it.";
1447 $MODEL = $model;
1448 last;
1449 }
1450 }
1451 1462
1452 $MODEL 1463 $MODEL
1453 or AnyEvent::log fatal => "AnyEvent: backend autodetection failed - did you properly install AnyEvent?"; 1464 or AnyEvent::log fatal => "Backend autodetection failed - did you properly install AnyEvent?";
1454 } 1465 }
1455 } 1466 }
1456 1467
1457 # free memory only needed for probing 1468 # free memory only needed for probing
1458 undef @models; 1469 undef @models;
… …
1605 # probe for availability of Time::HiRes 1616 # probe for availability of Time::HiRes
1606 if (eval "use Time::HiRes (); Time::HiRes::time (); 1") { 1617 if (eval "use Time::HiRes (); Time::HiRes::time (); 1") {
1607 *time = sub { Time::HiRes::time () }; 1618 *time = sub { Time::HiRes::time () };
1608 *AE::time = \& Time::HiRes::time ; 1619 *AE::time = \& Time::HiRes::time ;
1609 *now = \&time; 1620 *now = \&time;
1610 AnyEvent::log 8 => "AnyEvent: using Time::HiRes for sub-second timing accuracy."; 1621 AnyEvent::log 8 => "using Time::HiRes for sub-second timing accuracy.";
1611 # if (eval "use POSIX (); (POSIX::times())... 1622 # if (eval "use POSIX (); (POSIX::times())...
1612 } else { 1623 } else {
1613 *time = sub { CORE::time }; 1624 *time = sub { CORE::time };
1614 *AE::time = sub (){ CORE::time }; 1625 *AE::time = sub (){ CORE::time };
1615 *now = \&time; 1626 *now = \&time;
1616 AnyEvent::log 3 => "using built-in time(), WARNING, no sub-second resolution!"; 1627 AnyEvent::log 3 => "Using built-in time(), no sub-second resolution!";
1617 } 1628 }
1618 }; 1629 };
1619 die if $@; 1630 die if $@;
1620 1631
1621 &time 1632 &time
… …
1715 1726
1716sub signal { 1727sub signal {
1717 eval q{ # poor man's autoloading {} 1728 eval q{ # poor man's autoloading {}
1718 # probe for availability of Async::Interrupt 1729 # probe for availability of Async::Interrupt
1719 if (_have_async_interrupt) { 1730 if (_have_async_interrupt) {
1720 AnyEvent::log 8 => "using Async::Interrupt for race-free signal handling."; 1731 AnyEvent::log 8 => "Using Async::Interrupt for race-free signal handling.";
1721 1732
1722 $SIGPIPE_R = new Async::Interrupt::EventPipe; 1733 $SIGPIPE_R = new Async::Interrupt::EventPipe;
1723 $SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec; 1734 $SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec;
1724 1735
1725 } else { 1736 } else {
1726 AnyEvent::log 8 => "using emulated perl signal handling with latency timer."; 1737 AnyEvent::log 8 => "Using emulated perl signal handling with latency timer.";
1727 1738
1728 if (AnyEvent::WIN32) { 1739 if (AnyEvent::WIN32) {
1729 require AnyEvent::Util; 1740 require AnyEvent::Util;
1730 1741
1731 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe (); 1742 ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe ();
… …
2067 2078
2068=over 4 2079=over 4
2069 2080
2070=item C<PERL_ANYEVENT_VERBOSE> 2081=item C<PERL_ANYEVENT_VERBOSE>
2071 2082
2072By default, AnyEvent will only log messages with loglevel C<3> 2083By default, AnyEvent will log messages with loglevel C<4> (C<error>) or
2073(C<critical>) or higher (see L<AnyEvent::Log>). You can set this 2084higher (see L<AnyEvent::Log>). You can set this environment variable to a
2074environment variable to a numerical loglevel to make AnyEvent more (or 2085numerical loglevel to make AnyEvent more (or less) talkative.
2075less) talkative.
2076 2086
2077If you want to do more than just set the global logging level 2087If you want to do more than just set the global logging level
2078you should have a look at C<PERL_ANYEVENT_LOG>, which allows much more 2088you should have a look at C<PERL_ANYEVENT_LOG>, which allows much more
2079complex specifications. 2089complex specifications.
2080 2090
2081When set to C<0> (C<off>), then no messages whatsoever will be logged with 2091When set to C<0> (C<off>), then no messages whatsoever will be logged with
2082the default logging settings. 2092everything else at defaults.
2083 2093
2084When set to C<5> or higher (C<warn>), causes AnyEvent to warn about 2094When set to C<5> or higher (C<warn>), AnyEvent warns about unexpected
2085unexpected conditions, such as not being able to load the event model 2095conditions, such as not being able to load the event model specified by
2086specified by C<PERL_ANYEVENT_MODEL>, or a guard callback throwing an 2096C<PERL_ANYEVENT_MODEL>, or a guard callback throwing an exception - this
2087exception - this is the minimum recommended level. 2097is the minimum recommended level for use during development.
2088 2098
2089When set to C<7> or higher (info), cause AnyEvent to report which event model it 2099When set to C<7> or higher (info), AnyEvent reports which event model it
2090chooses. 2100chooses.
2091 2101
2092When set to C<8> or higher (debug), then AnyEvent will report extra information on 2102When set to C<8> or higher (debug), then AnyEvent will report extra
2093which optional modules it loads and how it implements certain features. 2103information on which optional modules it loads and how it implements
2104certain features.
2094 2105
2095=item C<PERL_ANYEVENT_LOG> 2106=item C<PERL_ANYEVENT_LOG>
2096 2107
2097Accepts rather complex logging specifications. For example, you could log 2108Accepts rather complex logging specifications. For example, you could log
2098all C<debug> messages of some module to stderr, warnings and above to 2109all C<debug> messages of some module to stderr, warnings and above to
… …
2105This variable is evaluated when AnyEvent (or L<AnyEvent::Log>) is loaded, 2116This variable is evaluated when AnyEvent (or L<AnyEvent::Log>) is loaded,
2106so will take effect even before AnyEvent has initialised itself. 2117so will take effect even before AnyEvent has initialised itself.
2107 2118
2108Note that specifying this environment variable causes the L<AnyEvent::Log> 2119Note that specifying this environment variable causes the L<AnyEvent::Log>
2109module to be loaded, while C<PERL_ANYEVENT_VERBOSE> does not, so only 2120module to be loaded, while C<PERL_ANYEVENT_VERBOSE> does not, so only
2110using the latter saves a few hundred kB of memory until the first message 2121using the latter saves a few hundred kB of memory unless a module
2111is being logged. 2122explicitly needs the extra features of AnyEvent::Log.
2112 2123
2113=item C<PERL_ANYEVENT_STRICT> 2124=item C<PERL_ANYEVENT_STRICT>
2114 2125
2115AnyEvent does not do much argument checking by default, as thorough 2126AnyEvent does not do much argument checking by default, as thorough
2116argument checking is very costly. Setting this variable to a true value 2127argument checking is very costly. Setting this variable to a true value
… …
2171For example, to force the pure perl model (L<AnyEvent::Loop::Perl>) you 2182For example, to force the pure perl model (L<AnyEvent::Loop::Perl>) you
2172could start your program like this: 2183could start your program like this:
2173 2184
2174 PERL_ANYEVENT_MODEL=Perl perl ... 2185 PERL_ANYEVENT_MODEL=Perl perl ...
2175 2186
2187=item C<PERL_ANYEVENT_IO_MODEL>
2188
2189The current file I/O model - see L<AnyEvent::IO> for more info.
2190
2191At the moment, only C<Perl> (small, pure-perl, synchronous) and
2192C<IOAIO> (truly asynchronous) are supported. The default is C<IOAIO> if
2193L<AnyEvent::AIO> can be loaded, otherwise it is C<Perl>.
2194
2176=item C<PERL_ANYEVENT_PROTOCOLS> 2195=item C<PERL_ANYEVENT_PROTOCOLS>
2177 2196
2178Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences 2197Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences
2179for IPv4 or IPv6. The default is unspecified (and might change, or be the result 2198for IPv4 or IPv6. The default is unspecified (and might change, or be the result
2180of auto probing). 2199of auto probing).
… …
2218=item C<PERL_ANYEVENT_MAX_OUTSTANDING_DNS> 2237=item C<PERL_ANYEVENT_MAX_OUTSTANDING_DNS>
2219 2238
2220The default value for the C<max_outstanding> parameter for the default DNS 2239The default value for the C<max_outstanding> parameter for the default DNS
2221resolver - this is the maximum number of parallel DNS requests that are 2240resolver - this is the maximum number of parallel DNS requests that are
2222sent to the DNS server. 2241sent to the DNS server.
2242
2243=item C<PERL_ANYEVENT_MAX_SIGNAL_LATENCY>
2244
2245Perl has inherently racy signal handling (you can basically choose between
2246losing signals and memory corruption) - pure perl event loops (including
2247C<AnyEvent::Loop>, when C<Async::Interrupt> isn't available) therefore
2248have to poll regularly to avoid losing signals.
2249
2250Some event loops are racy, but don't poll regularly, and some event loops
2251are written in C but are still racy. For those event loops, AnyEvent
2252installs a timer that regularly wakes up the event loop.
2253
2254By default, the interval for this timer is C<10> seconds, but you can
2255override this delay with this environment variable (or by setting
2256the C<$AnyEvent::MAX_SIGNAL_LATENCY> variable before creating signal
2257watchers).
2258
2259Lower values increase CPU (and energy) usage, higher values can introduce
2260long delays when reaping children or waiting for signals.
2261
2262The L<AnyEvent::Async> module, if available, will be used to avoid this
2263polling (with most event loops).
2223 2264
2224=item C<PERL_ANYEVENT_RESOLV_CONF> 2265=item C<PERL_ANYEVENT_RESOLV_CONF>
2225 2266
2226The absolute path to a F<resolv.conf>-style file to use instead of 2267The absolute path to a F<resolv.conf>-style file to use instead of
2227F</etc/resolv.conf> (or the OS-specific configuration) in the default 2268F</etc/resolv.conf> (or the OS-specific configuration) in the default
… …
2976L<AnyEvent::Impl::FLTK>. 3017L<AnyEvent::Impl::FLTK>.
2977 3018
2978Non-blocking handles, pipes, stream sockets, TCP clients and 3019Non-blocking handles, pipes, stream sockets, TCP clients and
2979servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>. 3020servers: L<AnyEvent::Handle>, L<AnyEvent::Socket>, L<AnyEvent::TLS>.
2980 3021
3022Asynchronous File I/O: L<AnyEvent::IO>.
3023
2981Asynchronous DNS: L<AnyEvent::DNS>. 3024Asynchronous DNS: L<AnyEvent::DNS>.
2982 3025
2983Thread support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>. 3026Thread support: L<Coro>, L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>.
2984 3027
2985Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::IRC>, 3028Nontrivial usage examples: L<AnyEvent::GPSD>, L<AnyEvent::IRC>,
… …
2987 3030
2988 3031
2989=head1 AUTHOR 3032=head1 AUTHOR
2990 3033
2991 Marc Lehmann <schmorp@schmorp.de> 3034 Marc Lehmann <schmorp@schmorp.de>
2992 http://home.schmorp.de/ 3035 http://anyevent.schmorp.de
2993 3036
2994=cut 3037=cut
2995 3038
29961 30391
2997 3040

Diff Legend

– Removed lines
+ Added lines
< Changed lines
> Changed lines