… | |
… | |
363 | might affect timers and time-outs. |
363 | might affect timers and time-outs. |
364 | |
364 | |
365 | When this is the case, you can call this method, which will update the |
365 | When this is the case, you can call this method, which will update the |
366 | event loop's idea of "current time". |
366 | event loop's idea of "current time". |
367 | |
367 | |
|
|
368 | A typical example would be a script in a web server (e.g. C<mod_perl>) - |
|
|
369 | when mod_perl executes the script, then the event loop will have the wrong |
|
|
370 | idea about the "current time" (being potentially far in the past, when the |
|
|
371 | script ran the last time). In that case you should arrange a call to C<< |
|
|
372 | AnyEvent->now_update >> each time the web server process wakes up again |
|
|
373 | (e.g. at the start of your script, or in a handler). |
|
|
374 | |
368 | Note that updating the time I<might> cause some events to be handled. |
375 | Note that updating the time I<might> cause some events to be handled. |
369 | |
376 | |
370 | =back |
377 | =back |
371 | |
378 | |
372 | =head2 SIGNAL WATCHERS |
379 | =head2 SIGNAL WATCHERS |
… | |
… | |
395 | correctly. |
402 | correctly. |
396 | |
403 | |
397 | Example: exit on SIGINT |
404 | Example: exit on SIGINT |
398 | |
405 | |
399 | my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 }); |
406 | my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 }); |
|
|
407 | |
|
|
408 | =head3 Restart Behaviour |
|
|
409 | |
|
|
410 | While restart behaviour is up to the event loop implementation, most will |
|
|
411 | not restart syscalls (that includes L<Async::Interrupt> and AnyEvent's |
|
|
412 | pure perl implementation). |
|
|
413 | |
|
|
414 | =head3 Safe/Unsafe Signals |
|
|
415 | |
|
|
416 | Perl signals can be either "safe" (synchronous to opcode handling) or |
|
|
417 | "unsafe" (asynchronous) - the former might get delayed indefinitely, the |
|
|
418 | latter might corrupt your memory. |
|
|
419 | |
|
|
420 | AnyEvent signal handlers are, in addition, synchronous to the event loop, |
|
|
421 | i.e. they will not interrupt your running perl program but will only be |
|
|
422 | called as part of the normal event handling (just like timer, I/O etc. |
|
|
423 | callbacks, too). |
400 | |
424 | |
401 | =head3 Signal Races, Delays and Workarounds |
425 | =head3 Signal Races, Delays and Workarounds |
402 | |
426 | |
403 | Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching |
427 | Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching |
404 | callbacks to signals in a generic way, which is a pity, as you cannot |
428 | callbacks to signals in a generic way, which is a pity, as you cannot |
… | |
… | |
479 | |
503 | |
480 | =head2 IDLE WATCHERS |
504 | =head2 IDLE WATCHERS |
481 | |
505 | |
482 | $w = AnyEvent->idle (cb => <callback>); |
506 | $w = AnyEvent->idle (cb => <callback>); |
483 | |
507 | |
484 | Sometimes there is a need to do something, but it is not so important |
508 | Repeatedly invoke the callback after the process becomes idle, until |
485 | to do it instantly, but only when there is nothing better to do. This |
509 | either the watcher is destroyed or new events have been detected. |
486 | "nothing better to do" is usually defined to be "no other events need |
|
|
487 | attention by the event loop". |
|
|
488 | |
510 | |
489 | Idle watchers ideally get invoked when the event loop has nothing |
511 | Idle watchers are useful when there is a need to do something, but it |
490 | better to do, just before it would block the process to wait for new |
512 | is not so important (or wise) to do it instantly. The callback will be |
491 | events. Instead of blocking, the idle watcher is invoked. |
513 | invoked only when there is "nothing better to do", which is usually |
|
|
514 | defined as "all outstanding events have been handled and no new events |
|
|
515 | have been detected". That means that idle watchers ideally get invoked |
|
|
516 | when the event loop has just polled for new events but none have been |
|
|
517 | detected. Instead of blocking to wait for more events, the idle watchers |
|
|
518 | will be invoked. |
492 | |
519 | |
493 | Most event loops unfortunately do not really support idle watchers (only |
520 | Unfortunately, most event loops do not really support idle watchers (only |
494 | EV, Event and Glib do it in a usable fashion) - for the rest, AnyEvent |
521 | EV, Event and Glib do it in a usable fashion) - for the rest, AnyEvent |
495 | will simply call the callback "from time to time". |
522 | will simply call the callback "from time to time". |
496 | |
523 | |
497 | Example: read lines from STDIN, but only process them when the |
524 | Example: read lines from STDIN, but only process them when the |
498 | program is otherwise idle: |
525 | program is otherwise idle: |
… | |
… | |
942 | You should check C<$AnyEvent::MODEL> before adding to this array, though: |
969 | You should check C<$AnyEvent::MODEL> before adding to this array, though: |
943 | if it is defined then the event loop has already been detected, and the |
970 | if it is defined then the event loop has already been detected, and the |
944 | array will be ignored. |
971 | array will be ignored. |
945 | |
972 | |
946 | Best use C<AnyEvent::post_detect { BLOCK }> when your application allows |
973 | Best use C<AnyEvent::post_detect { BLOCK }> when your application allows |
947 | it,as it takes care of these details. |
974 | it, as it takes care of these details. |
948 | |
975 | |
949 | This variable is mainly useful for modules that can do something useful |
976 | This variable is mainly useful for modules that can do something useful |
950 | when AnyEvent is used and thus want to know when it is initialised, but do |
977 | when AnyEvent is used and thus want to know when it is initialised, but do |
951 | not need to even load it by default. This array provides the means to hook |
978 | not need to even load it by default. This array provides the means to hook |
952 | into AnyEvent passively, without loading it. |
979 | into AnyEvent passively, without loading it. |
|
|
980 | |
|
|
981 | Example: To load Coro::AnyEvent whenever Coro and AnyEvent are used |
|
|
982 | together, you could put this into Coro (this is the actual code used by |
|
|
983 | Coro to accomplish this): |
|
|
984 | |
|
|
985 | if (defined $AnyEvent::MODEL) { |
|
|
986 | # AnyEvent already initialised, so load Coro::AnyEvent |
|
|
987 | require Coro::AnyEvent; |
|
|
988 | } else { |
|
|
989 | # AnyEvent not yet initialised, so make sure to load Coro::AnyEvent |
|
|
990 | # as soon as it is |
|
|
991 | push @AnyEvent::post_detect, sub { require Coro::AnyEvent }; |
|
|
992 | } |
953 | |
993 | |
954 | =back |
994 | =back |
955 | |
995 | |
956 | =head1 WHAT TO DO IN A MODULE |
996 | =head1 WHAT TO DO IN A MODULE |
957 | |
997 | |
… | |
… | |
1106 | |
1146 | |
1107 | package AnyEvent; |
1147 | package AnyEvent; |
1108 | |
1148 | |
1109 | # basically a tuned-down version of common::sense |
1149 | # basically a tuned-down version of common::sense |
1110 | sub common_sense { |
1150 | sub common_sense { |
1111 | # no warnings |
1151 | # from common:.sense 1.0 |
1112 | ${^WARNING_BITS} ^= ${^WARNING_BITS}; |
1152 | ${^WARNING_BITS} = "\xfc\x3f\x33\x00\x0f\xf3\xcf\xc0\xf3\xfc\x33\x00"; |
1113 | # use strict vars subs |
1153 | # use strict vars subs - NO UTF-8, as Util.pm doesn't like this atm. (uts46data.pl) |
1114 | $^H |= 0x00000600; |
1154 | $^H |= 0x00000600; |
1115 | } |
1155 | } |
1116 | |
1156 | |
1117 | BEGIN { AnyEvent::common_sense } |
1157 | BEGIN { AnyEvent::common_sense } |
1118 | |
1158 | |
1119 | use Carp (); |
1159 | use Carp (); |
1120 | |
1160 | |
1121 | our $VERSION = '5.112'; |
1161 | our $VERSION = '5.251'; |
1122 | our $MODEL; |
1162 | our $MODEL; |
1123 | |
1163 | |
1124 | our $AUTOLOAD; |
1164 | our $AUTOLOAD; |
1125 | our @ISA; |
1165 | our @ISA; |
1126 | |
1166 | |
1127 | our @REGISTRY; |
1167 | our @REGISTRY; |
1128 | |
1168 | |
1129 | our $WIN32; |
|
|
1130 | |
|
|
1131 | our $VERBOSE; |
1169 | our $VERBOSE; |
1132 | |
1170 | |
1133 | BEGIN { |
1171 | BEGIN { |
1134 | eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }"; |
1172 | require "AnyEvent/constants.pl"; |
|
|
1173 | |
1135 | eval "sub TAINT(){ " . (${^TAINT}*1) . " }"; |
1174 | eval "sub TAINT (){" . (${^TAINT}*1) . "}"; |
1136 | |
1175 | |
1137 | delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV} |
1176 | delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV} |
1138 | if ${^TAINT}; |
1177 | if ${^TAINT}; |
1139 | |
1178 | |
1140 | $VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1; |
1179 | $VERBOSE = $ENV{PERL_ANYEVENT_VERBOSE}*1; |
… | |
… | |
1183 | our @post_detect; |
1222 | our @post_detect; |
1184 | |
1223 | |
1185 | sub post_detect(&) { |
1224 | sub post_detect(&) { |
1186 | my ($cb) = @_; |
1225 | my ($cb) = @_; |
1187 | |
1226 | |
1188 | if ($MODEL) { |
|
|
1189 | $cb->(); |
|
|
1190 | |
|
|
1191 | undef |
|
|
1192 | } else { |
|
|
1193 | push @post_detect, $cb; |
1227 | push @post_detect, $cb; |
1194 | |
1228 | |
1195 | defined wantarray |
1229 | defined wantarray |
1196 | ? bless \$cb, "AnyEvent::Util::postdetect" |
1230 | ? bless \$cb, "AnyEvent::Util::postdetect" |
1197 | : () |
1231 | : () |
1198 | } |
|
|
1199 | } |
1232 | } |
1200 | |
1233 | |
1201 | sub AnyEvent::Util::postdetect::DESTROY { |
1234 | sub AnyEvent::Util::postdetect::DESTROY { |
1202 | @post_detect = grep $_ != ${$_[0]}, @post_detect; |
1235 | @post_detect = grep $_ != ${$_[0]}, @post_detect; |
1203 | } |
1236 | } |
1204 | |
1237 | |
1205 | sub detect() { |
1238 | sub detect() { |
|
|
1239 | # free some memory |
|
|
1240 | *detect = sub () { $MODEL }; |
|
|
1241 | |
|
|
1242 | local $!; # for good measure |
|
|
1243 | local $SIG{__DIE__}; |
|
|
1244 | |
|
|
1245 | if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) { |
|
|
1246 | my $model = "AnyEvent::Impl::$1"; |
|
|
1247 | if (eval "require $model") { |
|
|
1248 | $MODEL = $model; |
|
|
1249 | warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2; |
|
|
1250 | } else { |
|
|
1251 | warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE; |
|
|
1252 | } |
|
|
1253 | } |
|
|
1254 | |
|
|
1255 | # check for already loaded models |
1206 | unless ($MODEL) { |
1256 | unless ($MODEL) { |
1207 | local $SIG{__DIE__}; |
1257 | for (@REGISTRY, @models) { |
1208 | |
1258 | my ($package, $model) = @$_; |
1209 | if ($ENV{PERL_ANYEVENT_MODEL} =~ /^([a-zA-Z]+)$/) { |
1259 | if (${"$package\::VERSION"} > 0) { |
1210 | my $model = "AnyEvent::Impl::$1"; |
|
|
1211 | if (eval "require $model") { |
1260 | if (eval "require $model") { |
1212 | $MODEL = $model; |
1261 | $MODEL = $model; |
1213 | warn "AnyEvent: loaded model '$model' (forced by \$ENV{PERL_ANYEVENT_MODEL}), using it.\n" if $VERBOSE >= 2; |
1262 | warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2; |
1214 | } else { |
1263 | last; |
1215 | warn "AnyEvent: unable to load model '$model' (from \$ENV{PERL_ANYEVENT_MODEL}):\n$@" if $VERBOSE; |
1264 | } |
1216 | } |
1265 | } |
1217 | } |
1266 | } |
1218 | |
1267 | |
1219 | # check for already loaded models |
|
|
1220 | unless ($MODEL) { |
1268 | unless ($MODEL) { |
|
|
1269 | # try to autoload a model |
1221 | for (@REGISTRY, @models) { |
1270 | for (@REGISTRY, @models) { |
1222 | my ($package, $model) = @$_; |
1271 | my ($package, $model, $autoload) = @$_; |
|
|
1272 | if ( |
|
|
1273 | $autoload |
|
|
1274 | and eval "require $package" |
1223 | if (${"$package\::VERSION"} > 0) { |
1275 | and ${"$package\::VERSION"} > 0 |
1224 | if (eval "require $model") { |
1276 | and eval "require $model" |
|
|
1277 | ) { |
1225 | $MODEL = $model; |
1278 | $MODEL = $model; |
1226 | warn "AnyEvent: autodetected model '$model', using it.\n" if $VERBOSE >= 2; |
1279 | warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2; |
1227 | last; |
1280 | last; |
1228 | } |
|
|
1229 | } |
1281 | } |
1230 | } |
1282 | } |
1231 | |
1283 | |
1232 | unless ($MODEL) { |
|
|
1233 | # try to autoload a model |
|
|
1234 | for (@REGISTRY, @models) { |
|
|
1235 | my ($package, $model, $autoload) = @$_; |
|
|
1236 | if ( |
|
|
1237 | $autoload |
|
|
1238 | and eval "require $package" |
|
|
1239 | and ${"$package\::VERSION"} > 0 |
|
|
1240 | and eval "require $model" |
|
|
1241 | ) { |
|
|
1242 | $MODEL = $model; |
|
|
1243 | warn "AnyEvent: autoloaded model '$model', using it.\n" if $VERBOSE >= 2; |
|
|
1244 | last; |
|
|
1245 | } |
|
|
1246 | } |
|
|
1247 | |
|
|
1248 | $MODEL |
1284 | $MODEL |
1249 | or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.\n"; |
1285 | or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.\n"; |
1250 | } |
|
|
1251 | } |
1286 | } |
1252 | |
|
|
1253 | push @{"$MODEL\::ISA"}, "AnyEvent::Base"; |
|
|
1254 | |
|
|
1255 | unshift @ISA, $MODEL; |
|
|
1256 | |
|
|
1257 | require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT}; |
|
|
1258 | |
|
|
1259 | (shift @post_detect)->() while @post_detect; |
|
|
1260 | } |
1287 | } |
|
|
1288 | |
|
|
1289 | @models = (); # free probe data |
|
|
1290 | |
|
|
1291 | push @{"$MODEL\::ISA"}, "AnyEvent::Base"; |
|
|
1292 | unshift @ISA, $MODEL; |
|
|
1293 | |
|
|
1294 | # now nuke some methods that are overriden by the backend. |
|
|
1295 | # SUPER is not allowed. |
|
|
1296 | for (qw(time signal child idle)) { |
|
|
1297 | undef &{"AnyEvent::Base::$_"} |
|
|
1298 | if defined &{"$MODEL\::$_"}; |
|
|
1299 | } |
|
|
1300 | |
|
|
1301 | require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT}; |
|
|
1302 | |
|
|
1303 | (shift @post_detect)->() while @post_detect; |
|
|
1304 | |
|
|
1305 | *post_detect = sub(&) { |
|
|
1306 | shift->(); |
|
|
1307 | |
|
|
1308 | undef |
|
|
1309 | }; |
1261 | |
1310 | |
1262 | $MODEL |
1311 | $MODEL |
1263 | } |
1312 | } |
1264 | |
1313 | |
1265 | sub AUTOLOAD { |
1314 | sub AUTOLOAD { |
1266 | (my $func = $AUTOLOAD) =~ s/.*://; |
1315 | (my $func = $AUTOLOAD) =~ s/.*://; |
1267 | |
1316 | |
1268 | $method{$func} |
1317 | $method{$func} |
1269 | or Carp::croak "$func: not a valid method for AnyEvent objects"; |
1318 | or Carp::croak "$func: not a valid AnyEvent class method"; |
1270 | |
1319 | |
1271 | detect unless $MODEL; |
1320 | detect; |
1272 | |
1321 | |
1273 | my $class = shift; |
1322 | my $class = shift; |
1274 | $class->$func (@_); |
1323 | $class->$func (@_); |
1275 | } |
1324 | } |
1276 | |
1325 | |
… | |
… | |
1343 | |
1392 | |
1344 | package AnyEvent::Base; |
1393 | package AnyEvent::Base; |
1345 | |
1394 | |
1346 | # default implementations for many methods |
1395 | # default implementations for many methods |
1347 | |
1396 | |
1348 | sub _time { |
1397 | sub time { |
|
|
1398 | eval q{ # poor man's autoloading {} |
1349 | # probe for availability of Time::HiRes |
1399 | # probe for availability of Time::HiRes |
1350 | if (eval "use Time::HiRes (); Time::HiRes::time (); 1") { |
1400 | if (eval "use Time::HiRes (); Time::HiRes::time (); 1") { |
1351 | warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8; |
1401 | warn "AnyEvent: using Time::HiRes for sub-second timing accuracy.\n" if $VERBOSE >= 8; |
1352 | *_time = \&Time::HiRes::time; |
1402 | *AE::time = \&Time::HiRes::time; |
1353 | # if (eval "use POSIX (); (POSIX::times())... |
1403 | # if (eval "use POSIX (); (POSIX::times())... |
1354 | } else { |
1404 | } else { |
1355 | warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE; |
1405 | warn "AnyEvent: using built-in time(), WARNING, no sub-second resolution!\n" if $VERBOSE; |
1356 | *_time = sub { time }; # epic fail |
1406 | *AE::time = sub (){ time }; # epic fail |
|
|
1407 | } |
|
|
1408 | |
|
|
1409 | *time = sub { AE::time }; # different prototypes |
1357 | } |
1410 | }; |
|
|
1411 | die if $@; |
1358 | |
1412 | |
1359 | &_time |
1413 | &time |
1360 | } |
1414 | } |
1361 | |
1415 | |
1362 | sub time { _time } |
1416 | *now = \&time; |
1363 | sub now { _time } |
1417 | |
1364 | sub now_update { } |
1418 | sub now_update { } |
1365 | |
1419 | |
1366 | # default implementation for ->condvar |
1420 | # default implementation for ->condvar |
1367 | |
1421 | |
1368 | sub condvar { |
1422 | sub condvar { |
|
|
1423 | eval q{ # poor man's autoloading {} |
|
|
1424 | *condvar = sub { |
1369 | bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar" |
1425 | bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar" |
|
|
1426 | }; |
|
|
1427 | |
|
|
1428 | *AE::cv = sub (;&) { |
|
|
1429 | bless { @_ ? (_ae_cb => shift) : () }, "AnyEvent::CondVar" |
|
|
1430 | }; |
|
|
1431 | }; |
|
|
1432 | die if $@; |
|
|
1433 | |
|
|
1434 | &condvar |
1370 | } |
1435 | } |
1371 | |
1436 | |
1372 | # default implementation for ->signal |
1437 | # default implementation for ->signal |
1373 | |
1438 | |
1374 | our $HAVE_ASYNC_INTERRUPT; |
1439 | our $HAVE_ASYNC_INTERRUPT; |
1375 | |
1440 | |
1376 | sub _have_async_interrupt() { |
1441 | sub _have_async_interrupt() { |
1377 | $HAVE_ASYNC_INTERRUPT = 1*(!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT} |
1442 | $HAVE_ASYNC_INTERRUPT = 1*(!$ENV{PERL_ANYEVENT_AVOID_ASYNC_INTERRUPT} |
1378 | && eval "use Async::Interrupt 1.0 (); 1") |
1443 | && eval "use Async::Interrupt 1.02 (); 1") |
1379 | unless defined $HAVE_ASYNC_INTERRUPT; |
1444 | unless defined $HAVE_ASYNC_INTERRUPT; |
1380 | |
1445 | |
1381 | $HAVE_ASYNC_INTERRUPT |
1446 | $HAVE_ASYNC_INTERRUPT |
1382 | } |
1447 | } |
1383 | |
1448 | |
1384 | our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO); |
1449 | our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO); |
1385 | our (%SIG_ASY, %SIG_ASY_W); |
1450 | our (%SIG_ASY, %SIG_ASY_W); |
1386 | our ($SIG_COUNT, $SIG_TW); |
1451 | our ($SIG_COUNT, $SIG_TW); |
1387 | |
1452 | |
1388 | sub _signal_exec { |
|
|
1389 | $HAVE_ASYNC_INTERRUPT |
|
|
1390 | ? $SIGPIPE_R->drain |
|
|
1391 | : sysread $SIGPIPE_R, my $dummy, 9; |
|
|
1392 | |
|
|
1393 | while (%SIG_EV) { |
|
|
1394 | for (keys %SIG_EV) { |
|
|
1395 | delete $SIG_EV{$_}; |
|
|
1396 | $_->() for values %{ $SIG_CB{$_} || {} }; |
|
|
1397 | } |
|
|
1398 | } |
|
|
1399 | } |
|
|
1400 | |
|
|
1401 | # install a dummy wakeup watcher to reduce signal catching latency |
1453 | # install a dummy wakeup watcher to reduce signal catching latency |
|
|
1454 | # used by Impls |
1402 | sub _sig_add() { |
1455 | sub _sig_add() { |
1403 | unless ($SIG_COUNT++) { |
1456 | unless ($SIG_COUNT++) { |
1404 | # try to align timer on a full-second boundary, if possible |
1457 | # try to align timer on a full-second boundary, if possible |
1405 | my $NOW = AE::now; |
1458 | my $NOW = AE::now; |
1406 | |
1459 | |
… | |
… | |
1416 | undef $SIG_TW |
1469 | undef $SIG_TW |
1417 | unless --$SIG_COUNT; |
1470 | unless --$SIG_COUNT; |
1418 | } |
1471 | } |
1419 | |
1472 | |
1420 | our $_sig_name_init; $_sig_name_init = sub { |
1473 | our $_sig_name_init; $_sig_name_init = sub { |
1421 | eval q{ # poor man's autoloading |
1474 | eval q{ # poor man's autoloading {} |
1422 | undef $_sig_name_init; |
1475 | undef $_sig_name_init; |
1423 | |
1476 | |
1424 | if (_have_async_interrupt) { |
1477 | if (_have_async_interrupt) { |
1425 | *sig2num = \&Async::Interrupt::sig2num; |
1478 | *sig2num = \&Async::Interrupt::sig2num; |
1426 | *sig2name = \&Async::Interrupt::sig2name; |
1479 | *sig2name = \&Async::Interrupt::sig2name; |
… | |
… | |
1458 | $SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec; |
1511 | $SIG_IO = AE::io $SIGPIPE_R->fileno, 0, \&_signal_exec; |
1459 | |
1512 | |
1460 | } else { |
1513 | } else { |
1461 | warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8; |
1514 | warn "AnyEvent: using emulated perl signal handling with latency timer.\n" if $VERBOSE >= 8; |
1462 | |
1515 | |
1463 | require Fcntl; |
|
|
1464 | |
|
|
1465 | if (AnyEvent::WIN32) { |
1516 | if (AnyEvent::WIN32) { |
1466 | require AnyEvent::Util; |
1517 | require AnyEvent::Util; |
1467 | |
1518 | |
1468 | ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe (); |
1519 | ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe (); |
1469 | AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R; |
1520 | AnyEvent::Util::fh_nonblocking ($SIGPIPE_R, 1) if $SIGPIPE_R; |
1470 | AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case |
1521 | AnyEvent::Util::fh_nonblocking ($SIGPIPE_W, 1) if $SIGPIPE_W; # just in case |
1471 | } else { |
1522 | } else { |
1472 | pipe $SIGPIPE_R, $SIGPIPE_W; |
1523 | pipe $SIGPIPE_R, $SIGPIPE_W; |
1473 | fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R; |
1524 | fcntl $SIGPIPE_R, AnyEvent::F_SETFL, AnyEvent::O_NONBLOCK if $SIGPIPE_R; |
1474 | fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case |
1525 | fcntl $SIGPIPE_W, AnyEvent::F_SETFL, AnyEvent::O_NONBLOCK if $SIGPIPE_W; # just in case |
1475 | |
1526 | |
1476 | # not strictly required, as $^F is normally 2, but let's make sure... |
1527 | # not strictly required, as $^F is normally 2, but let's make sure... |
1477 | fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; |
1528 | fcntl $SIGPIPE_R, AnyEvent::F_SETFD, AnyEvent::FD_CLOEXEC; |
1478 | fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; |
1529 | fcntl $SIGPIPE_W, AnyEvent::F_SETFD, AnyEvent::FD_CLOEXEC; |
1479 | } |
1530 | } |
1480 | |
1531 | |
1481 | $SIGPIPE_R |
1532 | $SIGPIPE_R |
1482 | or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n"; |
1533 | or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n"; |
1483 | |
1534 | |
1484 | $SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec; |
1535 | $SIG_IO = AE::io $SIGPIPE_R, 0, \&_signal_exec; |
1485 | } |
1536 | } |
1486 | |
1537 | |
1487 | *signal = sub { |
1538 | *signal = $HAVE_ASYNC_INTERRUPT |
|
|
1539 | ? sub { |
1488 | my (undef, %arg) = @_; |
1540 | my (undef, %arg) = @_; |
1489 | |
1541 | |
1490 | my $signal = uc $arg{signal} |
|
|
1491 | or Carp::croak "required option 'signal' is missing"; |
|
|
1492 | |
|
|
1493 | if ($HAVE_ASYNC_INTERRUPT) { |
|
|
1494 | # async::interrupt |
1542 | # async::interrupt |
1495 | |
|
|
1496 | $signal = sig2num $signal; |
1543 | my $signal = sig2num $arg{signal}; |
1497 | $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; |
1544 | $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; |
1498 | |
1545 | |
1499 | $SIG_ASY{$signal} ||= new Async::Interrupt |
1546 | $SIG_ASY{$signal} ||= new Async::Interrupt |
1500 | cb => sub { undef $SIG_EV{$signal} }, |
1547 | cb => sub { undef $SIG_EV{$signal} }, |
1501 | signal => $signal, |
1548 | signal => $signal, |
1502 | pipe => [$SIGPIPE_R->filenos], |
1549 | pipe => [$SIGPIPE_R->filenos], |
1503 | pipe_autodrain => 0, |
1550 | pipe_autodrain => 0, |
1504 | ; |
1551 | ; |
1505 | |
1552 | |
1506 | } else { |
1553 | bless [$signal, $arg{cb}], "AnyEvent::Base::signal" |
|
|
1554 | } |
|
|
1555 | : sub { |
|
|
1556 | my (undef, %arg) = @_; |
|
|
1557 | |
1507 | # pure perl |
1558 | # pure perl |
1508 | |
|
|
1509 | # AE::Util has been loaded in signal |
|
|
1510 | $signal = sig2name $signal; |
1559 | my $signal = sig2name $arg{signal}; |
1511 | $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; |
1560 | $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; |
1512 | |
1561 | |
1513 | $SIG{$signal} ||= sub { |
1562 | $SIG{$signal} ||= sub { |
1514 | local $!; |
1563 | local $!; |
1515 | syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV; |
1564 | syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV; |
1516 | undef $SIG_EV{$signal}; |
1565 | undef $SIG_EV{$signal}; |
1517 | }; |
1566 | }; |
1518 | |
1567 | |
1519 | # can't do signal processing without introducing races in pure perl, |
1568 | # can't do signal processing without introducing races in pure perl, |
1520 | # so limit the signal latency. |
1569 | # so limit the signal latency. |
1521 | _sig_add; |
1570 | _sig_add; |
1522 | } |
|
|
1523 | |
1571 | |
1524 | bless [$signal, $arg{cb}], "AnyEvent::Base::signal" |
1572 | bless [$signal, $arg{cb}], "AnyEvent::Base::signal" |
|
|
1573 | } |
1525 | }; |
1574 | ; |
1526 | |
1575 | |
1527 | *AnyEvent::Base::signal::DESTROY = sub { |
1576 | *AnyEvent::Base::signal::DESTROY = sub { |
1528 | my ($signal, $cb) = @{$_[0]}; |
1577 | my ($signal, $cb) = @{$_[0]}; |
1529 | |
1578 | |
1530 | _sig_del; |
1579 | _sig_del; |
… | |
… | |
1537 | # print weird messages, or just unconditionally exit |
1586 | # print weird messages, or just unconditionally exit |
1538 | # instead of getting the default action. |
1587 | # instead of getting the default action. |
1539 | undef $SIG{$signal} |
1588 | undef $SIG{$signal} |
1540 | unless keys %{ $SIG_CB{$signal} }; |
1589 | unless keys %{ $SIG_CB{$signal} }; |
1541 | }; |
1590 | }; |
|
|
1591 | |
|
|
1592 | *_signal_exec = sub { |
|
|
1593 | $HAVE_ASYNC_INTERRUPT |
|
|
1594 | ? $SIGPIPE_R->drain |
|
|
1595 | : sysread $SIGPIPE_R, (my $dummy), 9; |
|
|
1596 | |
|
|
1597 | while (%SIG_EV) { |
|
|
1598 | for (keys %SIG_EV) { |
|
|
1599 | delete $SIG_EV{$_}; |
|
|
1600 | $_->() for values %{ $SIG_CB{$_} || {} }; |
|
|
1601 | } |
|
|
1602 | } |
|
|
1603 | }; |
1542 | }; |
1604 | }; |
1543 | die if $@; |
1605 | die if $@; |
|
|
1606 | |
1544 | &signal |
1607 | &signal |
1545 | } |
1608 | } |
1546 | |
1609 | |
1547 | # default implementation for ->child |
1610 | # default implementation for ->child |
1548 | |
1611 | |
1549 | our %PID_CB; |
1612 | our %PID_CB; |
1550 | our $CHLD_W; |
1613 | our $CHLD_W; |
1551 | our $CHLD_DELAY_W; |
1614 | our $CHLD_DELAY_W; |
1552 | our $WNOHANG; |
1615 | our $WNOHANG; |
1553 | |
1616 | |
|
|
1617 | # used by many Impl's |
1554 | sub _emit_childstatus($$) { |
1618 | sub _emit_childstatus($$) { |
1555 | my (undef, $rpid, $rstatus) = @_; |
1619 | my (undef, $rpid, $rstatus) = @_; |
1556 | |
1620 | |
1557 | $_->($rpid, $rstatus) |
1621 | $_->($rpid, $rstatus) |
1558 | for values %{ $PID_CB{$rpid} || {} }, |
1622 | for values %{ $PID_CB{$rpid} || {} }, |
1559 | values %{ $PID_CB{0} || {} }; |
1623 | values %{ $PID_CB{0} || {} }; |
1560 | } |
1624 | } |
1561 | |
1625 | |
1562 | sub _sigchld { |
|
|
1563 | my $pid; |
|
|
1564 | |
|
|
1565 | AnyEvent->_emit_childstatus ($pid, $?) |
|
|
1566 | while ($pid = waitpid -1, $WNOHANG) > 0; |
|
|
1567 | } |
|
|
1568 | |
|
|
1569 | sub child { |
1626 | sub child { |
|
|
1627 | eval q{ # poor man's autoloading {} |
|
|
1628 | *_sigchld = sub { |
|
|
1629 | my $pid; |
|
|
1630 | |
|
|
1631 | AnyEvent->_emit_childstatus ($pid, $?) |
|
|
1632 | while ($pid = waitpid -1, $WNOHANG) > 0; |
|
|
1633 | }; |
|
|
1634 | |
|
|
1635 | *child = sub { |
1570 | my (undef, %arg) = @_; |
1636 | my (undef, %arg) = @_; |
1571 | |
1637 | |
1572 | defined (my $pid = $arg{pid} + 0) |
1638 | defined (my $pid = $arg{pid} + 0) |
1573 | or Carp::croak "required option 'pid' is missing"; |
1639 | or Carp::croak "required option 'pid' is missing"; |
1574 | |
1640 | |
1575 | $PID_CB{$pid}{$arg{cb}} = $arg{cb}; |
1641 | $PID_CB{$pid}{$arg{cb}} = $arg{cb}; |
1576 | |
1642 | |
1577 | # WNOHANG is almost cetrainly 1 everywhere |
1643 | # WNOHANG is almost cetrainly 1 everywhere |
1578 | $WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/ |
1644 | $WNOHANG ||= $^O =~ /^(?:openbsd|netbsd|linux|freebsd|cygwin|MSWin32)$/ |
1579 | ? 1 |
1645 | ? 1 |
1580 | : eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1; |
1646 | : eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1; |
1581 | |
1647 | |
1582 | unless ($CHLD_W) { |
1648 | unless ($CHLD_W) { |
1583 | $CHLD_W = AE::signal CHLD => \&_sigchld; |
1649 | $CHLD_W = AE::signal CHLD => \&_sigchld; |
1584 | # child could be a zombie already, so make at least one round |
1650 | # child could be a zombie already, so make at least one round |
1585 | &_sigchld; |
1651 | &_sigchld; |
1586 | } |
1652 | } |
1587 | |
1653 | |
1588 | bless [$pid, $arg{cb}], "AnyEvent::Base::child" |
1654 | bless [$pid, $arg{cb}], "AnyEvent::Base::child" |
1589 | } |
1655 | }; |
1590 | |
1656 | |
1591 | sub AnyEvent::Base::child::DESTROY { |
1657 | *AnyEvent::Base::child::DESTROY = sub { |
1592 | my ($pid, $cb) = @{$_[0]}; |
1658 | my ($pid, $cb) = @{$_[0]}; |
1593 | |
1659 | |
1594 | delete $PID_CB{$pid}{$cb}; |
1660 | delete $PID_CB{$pid}{$cb}; |
1595 | delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} }; |
1661 | delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} }; |
1596 | |
1662 | |
1597 | undef $CHLD_W unless keys %PID_CB; |
1663 | undef $CHLD_W unless keys %PID_CB; |
|
|
1664 | }; |
|
|
1665 | }; |
|
|
1666 | die if $@; |
|
|
1667 | |
|
|
1668 | &child |
1598 | } |
1669 | } |
1599 | |
1670 | |
1600 | # idle emulation is done by simply using a timer, regardless |
1671 | # idle emulation is done by simply using a timer, regardless |
1601 | # of whether the process is idle or not, and not letting |
1672 | # of whether the process is idle or not, and not letting |
1602 | # the callback use more than 50% of the time. |
1673 | # the callback use more than 50% of the time. |
1603 | sub idle { |
1674 | sub idle { |
|
|
1675 | eval q{ # poor man's autoloading {} |
|
|
1676 | *idle = sub { |
1604 | my (undef, %arg) = @_; |
1677 | my (undef, %arg) = @_; |
1605 | |
1678 | |
1606 | my ($cb, $w, $rcb) = $arg{cb}; |
1679 | my ($cb, $w, $rcb) = $arg{cb}; |
1607 | |
1680 | |
1608 | $rcb = sub { |
1681 | $rcb = sub { |
1609 | if ($cb) { |
1682 | if ($cb) { |
1610 | $w = _time; |
1683 | $w = _time; |
1611 | &$cb; |
1684 | &$cb; |
1612 | $w = _time - $w; |
1685 | $w = _time - $w; |
1613 | |
1686 | |
1614 | # never use more then 50% of the time for the idle watcher, |
1687 | # never use more then 50% of the time for the idle watcher, |
1615 | # within some limits |
1688 | # within some limits |
1616 | $w = 0.0001 if $w < 0.0001; |
1689 | $w = 0.0001 if $w < 0.0001; |
1617 | $w = 5 if $w > 5; |
1690 | $w = 5 if $w > 5; |
1618 | |
1691 | |
1619 | $w = AE::timer $w, 0, $rcb; |
1692 | $w = AE::timer $w, 0, $rcb; |
1620 | } else { |
1693 | } else { |
1621 | # clean up... |
1694 | # clean up... |
1622 | undef $w; |
1695 | undef $w; |
1623 | undef $rcb; |
1696 | undef $rcb; |
|
|
1697 | } |
|
|
1698 | }; |
|
|
1699 | |
|
|
1700 | $w = AE::timer 0.05, 0, $rcb; |
|
|
1701 | |
|
|
1702 | bless \\$cb, "AnyEvent::Base::idle" |
1624 | } |
1703 | }; |
|
|
1704 | |
|
|
1705 | *AnyEvent::Base::idle::DESTROY = sub { |
|
|
1706 | undef $${$_[0]}; |
|
|
1707 | }; |
1625 | }; |
1708 | }; |
|
|
1709 | die if $@; |
1626 | |
1710 | |
1627 | $w = AE::timer 0.05, 0, $rcb; |
1711 | &idle |
1628 | |
|
|
1629 | bless \\$cb, "AnyEvent::Base::idle" |
|
|
1630 | } |
|
|
1631 | |
|
|
1632 | sub AnyEvent::Base::idle::DESTROY { |
|
|
1633 | undef $${$_[0]}; |
|
|
1634 | } |
1712 | } |
1635 | |
1713 | |
1636 | package AnyEvent::CondVar; |
1714 | package AnyEvent::CondVar; |
1637 | |
1715 | |
1638 | our @ISA = AnyEvent::CondVar::Base::; |
1716 | our @ISA = AnyEvent::CondVar::Base::; |
… | |
… | |
1912 | warn "read: $input\n"; # output what has been read |
1990 | warn "read: $input\n"; # output what has been read |
1913 | $cv->send if $input =~ /^q/i; # quit program if /^q/i |
1991 | $cv->send if $input =~ /^q/i; # quit program if /^q/i |
1914 | }, |
1992 | }, |
1915 | ); |
1993 | ); |
1916 | |
1994 | |
1917 | my $time_watcher; # can only be used once |
|
|
1918 | |
|
|
1919 | sub new_timer { |
|
|
1920 | $timer = AnyEvent->timer (after => 1, cb => sub { |
1995 | my $time_watcher = AnyEvent->timer (after => 1, interval => 1, cb => sub { |
1921 | warn "timeout\n"; # print 'timeout' about every second |
1996 | warn "timeout\n"; # print 'timeout' at most every second |
1922 | &new_timer; # and restart the time |
|
|
1923 | }); |
1997 | }); |
1924 | } |
|
|
1925 | |
|
|
1926 | new_timer; # create first timer |
|
|
1927 | |
1998 | |
1928 | $cv->recv; # wait until user enters /^q/i |
1999 | $cv->recv; # wait until user enters /^q/i |
1929 | |
2000 | |
1930 | =head1 REAL-WORLD EXAMPLE |
2001 | =head1 REAL-WORLD EXAMPLE |
1931 | |
2002 | |
… | |
… | |
2375 | As you can see, the AnyEvent + EV combination even beats the |
2446 | As you can see, the AnyEvent + EV combination even beats the |
2376 | hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl |
2447 | hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl |
2377 | backend easily beats IO::Lambda and POE. |
2448 | backend easily beats IO::Lambda and POE. |
2378 | |
2449 | |
2379 | And even the 100% non-blocking version written using the high-level (and |
2450 | And even the 100% non-blocking version written using the high-level (and |
2380 | slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda by a |
2451 | slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda |
2381 | large margin, even though it does all of DNS, tcp-connect and socket I/O |
2452 | higher level ("unoptimised") abstractions by a large margin, even though |
2382 | in a non-blocking way. |
2453 | it does all of DNS, tcp-connect and socket I/O in a non-blocking way. |
2383 | |
2454 | |
2384 | The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and |
2455 | The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and |
2385 | F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are |
2456 | F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are |
2386 | part of the IO::lambda distribution and were used without any changes. |
2457 | part of the IO::Lambda distribution and were used without any changes. |
2387 | |
2458 | |
2388 | |
2459 | |
2389 | =head1 SIGNALS |
2460 | =head1 SIGNALS |
2390 | |
2461 | |
2391 | AnyEvent currently installs handlers for these signals: |
2462 | AnyEvent currently installs handlers for these signals: |
… | |
… | |
2433 | it's built-in modules) are required to use it. |
2504 | it's built-in modules) are required to use it. |
2434 | |
2505 | |
2435 | That does not mean that AnyEvent won't take advantage of some additional |
2506 | That does not mean that AnyEvent won't take advantage of some additional |
2436 | modules if they are installed. |
2507 | modules if they are installed. |
2437 | |
2508 | |
2438 | This section epxlains which additional modules will be used, and how they |
2509 | This section explains which additional modules will be used, and how they |
2439 | affect AnyEvent's operetion. |
2510 | affect AnyEvent's operation. |
2440 | |
2511 | |
2441 | =over 4 |
2512 | =over 4 |
2442 | |
2513 | |
2443 | =item L<Async::Interrupt> |
2514 | =item L<Async::Interrupt> |
2444 | |
2515 | |
… | |
… | |
2449 | catch the signals) with some delay (default is 10 seconds, look for |
2520 | catch the signals) with some delay (default is 10 seconds, look for |
2450 | C<$AnyEvent::MAX_SIGNAL_LATENCY>). |
2521 | C<$AnyEvent::MAX_SIGNAL_LATENCY>). |
2451 | |
2522 | |
2452 | If this module is available, then it will be used to implement signal |
2523 | If this module is available, then it will be used to implement signal |
2453 | catching, which means that signals will not be delayed, and the event loop |
2524 | catching, which means that signals will not be delayed, and the event loop |
2454 | will not be interrupted regularly, which is more efficient (And good for |
2525 | will not be interrupted regularly, which is more efficient (and good for |
2455 | battery life on laptops). |
2526 | battery life on laptops). |
2456 | |
2527 | |
2457 | This affects not just the pure-perl event loop, but also other event loops |
2528 | This affects not just the pure-perl event loop, but also other event loops |
2458 | that have no signal handling on their own (e.g. Glib, Tk, Qt). |
2529 | that have no signal handling on their own (e.g. Glib, Tk, Qt). |
2459 | |
2530 | |
… | |
… | |
2471 | automatic timer adjustments even when no monotonic clock is available, |
2542 | automatic timer adjustments even when no monotonic clock is available, |
2472 | can take avdantage of advanced kernel interfaces such as C<epoll> and |
2543 | can take avdantage of advanced kernel interfaces such as C<epoll> and |
2473 | C<kqueue>, and is the fastest backend I<by far>. You can even embed |
2544 | C<kqueue>, and is the fastest backend I<by far>. You can even embed |
2474 | L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>). |
2545 | L<Glib>/L<Gtk2> in it (or vice versa, see L<EV::Glib> and L<Glib::EV>). |
2475 | |
2546 | |
|
|
2547 | If you only use backends that rely on another event loop (e.g. C<Tk>), |
|
|
2548 | then this module will do nothing for you. |
|
|
2549 | |
2476 | =item L<Guard> |
2550 | =item L<Guard> |
2477 | |
2551 | |
2478 | The guard module, when used, will be used to implement |
2552 | The guard module, when used, will be used to implement |
2479 | C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a |
2553 | C<AnyEvent::Util::guard>. This speeds up guards considerably (and uses a |
2480 | lot less memory), but otherwise doesn't affect guard operation much. It is |
2554 | lot less memory), but otherwise doesn't affect guard operation much. It is |
2481 | purely used for performance. |
2555 | purely used for performance. |
2482 | |
2556 | |
2483 | =item L<JSON> and L<JSON::XS> |
2557 | =item L<JSON> and L<JSON::XS> |
2484 | |
2558 | |
2485 | This module is required when you want to read or write JSON data via |
2559 | One of these modules is required when you want to read or write JSON data |
2486 | L<AnyEvent::Handle>. It is also written in pure-perl, but can take |
2560 | via L<AnyEvent::Handle>. L<JSON> is also written in pure-perl, but can take |
2487 | advantage of the ultra-high-speed L<JSON::XS> module when it is installed. |
2561 | advantage of the ultra-high-speed L<JSON::XS> module when it is installed. |
2488 | |
|
|
2489 | In fact, L<AnyEvent::Handle> will use L<JSON::XS> by default if it is |
|
|
2490 | installed. |
|
|
2491 | |
2562 | |
2492 | =item L<Net::SSLeay> |
2563 | =item L<Net::SSLeay> |
2493 | |
2564 | |
2494 | Implementing TLS/SSL in Perl is certainly interesting, but not very |
2565 | Implementing TLS/SSL in Perl is certainly interesting, but not very |
2495 | worthwhile: If this module is installed, then L<AnyEvent::Handle> (with |
2566 | worthwhile: If this module is installed, then L<AnyEvent::Handle> (with |
… | |
… | |
2506 | |
2577 | |
2507 | |
2578 | |
2508 | =head1 FORK |
2579 | =head1 FORK |
2509 | |
2580 | |
2510 | Most event libraries are not fork-safe. The ones who are usually are |
2581 | Most event libraries are not fork-safe. The ones who are usually are |
2511 | because they rely on inefficient but fork-safe C<select> or C<poll> |
2582 | because they rely on inefficient but fork-safe C<select> or C<poll> calls |
2512 | calls. Only L<EV> is fully fork-aware. |
2583 | - higher performance APIs such as BSD's kqueue or the dreaded Linux epoll |
|
|
2584 | are usually badly thought-out hacks that are incompatible with fork in |
|
|
2585 | one way or another. Only L<EV> is fully fork-aware and ensures that you |
|
|
2586 | continue event-processing in both parent and child (or both, if you know |
|
|
2587 | what you are doing). |
|
|
2588 | |
|
|
2589 | This means that, in general, you cannot fork and do event processing in |
|
|
2590 | the child if the event library was initialised before the fork (which |
|
|
2591 | usually happens when the first AnyEvent watcher is created, or the library |
|
|
2592 | is loaded). |
2513 | |
2593 | |
2514 | If you have to fork, you must either do so I<before> creating your first |
2594 | If you have to fork, you must either do so I<before> creating your first |
2515 | watcher OR you must not use AnyEvent at all in the child OR you must do |
2595 | watcher OR you must not use AnyEvent at all in the child OR you must do |
2516 | something completely out of the scope of AnyEvent. |
2596 | something completely out of the scope of AnyEvent. |
|
|
2597 | |
|
|
2598 | The problem of doing event processing in the parent I<and> the child |
|
|
2599 | is much more complicated: even for backends that I<are> fork-aware or |
|
|
2600 | fork-safe, their behaviour is not usually what you want: fork clones all |
|
|
2601 | watchers, that means all timers, I/O watchers etc. are active in both |
|
|
2602 | parent and child, which is almost never what you want. USing C<exec> |
|
|
2603 | to start worker children from some kind of manage rprocess is usually |
|
|
2604 | preferred, because it is much easier and cleaner, at the expense of having |
|
|
2605 | to have another binary. |
2517 | |
2606 | |
2518 | |
2607 | |
2519 | =head1 SECURITY CONSIDERATIONS |
2608 | =head1 SECURITY CONSIDERATIONS |
2520 | |
2609 | |
2521 | AnyEvent can be forced to load any event model via |
2610 | AnyEvent can be forced to load any event model via |