… | |
… | |
403 | will not restart syscalls (that includes Async::Interrupt and AnyEvent's |
403 | will not restart syscalls (that includes Async::Interrupt and AnyEvent's |
404 | pure perl implementation). |
404 | pure perl implementation). |
405 | |
405 | |
406 | Safe/Unsafe Signals |
406 | Safe/Unsafe Signals |
407 | Perl signals can be either "safe" (synchronous to opcode handling) or |
407 | Perl signals can be either "safe" (synchronous to opcode handling) or |
408 | "unsafe" (asynchronous) - the former might get delayed indefinitely, the |
408 | "unsafe" (asynchronous) - the former might delay signal delivery |
409 | latter might corrupt your memory. |
409 | indefinitely, the latter might corrupt your memory. |
410 | |
410 | |
411 | AnyEvent signal handlers are, in addition, synchronous to the event |
411 | AnyEvent signal handlers are, in addition, synchronous to the event |
412 | loop, i.e. they will not interrupt your running perl program but will |
412 | loop, i.e. they will not interrupt your running perl program but will |
413 | only be called as part of the normal event handling (just like timer, |
413 | only be called as part of the normal event handling (just like timer, |
414 | I/O etc. callbacks, too). |
414 | I/O etc. callbacks, too). |
… | |
… | |
416 | Signal Races, Delays and Workarounds |
416 | Signal Races, Delays and Workarounds |
417 | Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching |
417 | Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching |
418 | callbacks to signals in a generic way, which is a pity, as you cannot do |
418 | callbacks to signals in a generic way, which is a pity, as you cannot do |
419 | race-free signal handling in perl, requiring C libraries for this. |
419 | race-free signal handling in perl, requiring C libraries for this. |
420 | AnyEvent will try to do its best, which means in some cases, signals |
420 | AnyEvent will try to do its best, which means in some cases, signals |
421 | will be delayed. The maximum time a signal might be delayed is specified |
421 | will be delayed. The maximum time a signal might be delayed is 10 |
422 | in $AnyEvent::MAX_SIGNAL_LATENCY (default: 10 seconds). This variable |
422 | seconds by default, but can be overriden via |
423 | can be changed only before the first signal watcher is created, and |
423 | $ENV{PERL_ANYEVENT_MAX_SIGNAL_LATENCY} or $AnyEvent::MAX_SIGNAL_LATENCY |
424 | should be left alone otherwise. This variable determines how often |
424 | - see the "ENVIRONMENT VARIABLES" section for details. |
425 | AnyEvent polls for signals (in case a wake-up was missed). Higher values |
|
|
426 | will cause fewer spurious wake-ups, which is better for power and CPU |
|
|
427 | saving. |
|
|
428 | |
425 | |
429 | All these problems can be avoided by installing the optional |
426 | All these problems can be avoided by installing the optional |
430 | Async::Interrupt module, which works with most event loops. It will not |
427 | Async::Interrupt module, which works with most event loops. It will not |
431 | work with inherently broken event loops such as Event or Event::Lib (and |
428 | work with inherently broken event loops such as Event or Event::Lib (and |
432 | not with POE currently, as POE does its own workaround with one-second |
|
|
433 | latency). For those, you just have to suffer the delays. |
429 | not with POE currently). For those, you just have to suffer the delays. |
434 | |
430 | |
435 | CHILD PROCESS WATCHERS |
431 | CHILD PROCESS WATCHERS |
436 | $w = AnyEvent->child (pid => <process id>, cb => <callback>); |
432 | $w = AnyEvent->child (pid => <process id>, cb => <callback>); |
437 | |
433 | |
438 | You can also watch for a child process exit and catch its exit status. |
434 | You can also watch for a child process exit and catch its exit status. |
… | |
… | |
839 | AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. |
835 | AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. |
840 | AnyEvent::Impl::POE based on POE, very slow, some limitations. |
836 | AnyEvent::Impl::POE based on POE, very slow, some limitations. |
841 | AnyEvent::Impl::Irssi used when running within irssi. |
837 | AnyEvent::Impl::Irssi used when running within irssi. |
842 | AnyEvent::Impl::IOAsync based on IO::Async. |
838 | AnyEvent::Impl::IOAsync based on IO::Async. |
843 | AnyEvent::Impl::Cocoa based on Cocoa::EventLoop. |
839 | AnyEvent::Impl::Cocoa based on Cocoa::EventLoop. |
844 | AnyEvent::Impl::FLTK2 based on FLTK (fltk 2 binding). |
840 | AnyEvent::Impl::FLTK based on FLTK (fltk 2 binding). |
845 | |
841 | |
846 | Backends with special needs. |
842 | Backends with special needs. |
847 | Qt requires the Qt::Application to be instantiated first, but will |
843 | Qt requires the Qt::Application to be instantiated first, but will |
848 | otherwise be picked up automatically. As long as the main program |
844 | otherwise be picked up automatically. As long as the main program |
849 | instantiates the application before any AnyEvent watchers are |
845 | instantiates the application before any AnyEvent watchers are |
… | |
… | |
1010 | If AnyEvent::Log is not loaded then this function makes a simple |
1006 | If AnyEvent::Log is not loaded then this function makes a simple |
1011 | test to see whether the message will be logged. If the test succeeds |
1007 | test to see whether the message will be logged. If the test succeeds |
1012 | it will load AnyEvent::Log and call "AnyEvent::Log::log" - |
1008 | it will load AnyEvent::Log and call "AnyEvent::Log::log" - |
1013 | consequently, look at the AnyEvent::Log documentation for details. |
1009 | consequently, look at the AnyEvent::Log documentation for details. |
1014 | |
1010 | |
1015 | If the test fails it will simply return. |
1011 | If the test fails it will simply return. Right now this happens when |
|
|
1012 | a numerical loglevel is used and it is larger than the level |
|
|
1013 | specified via $ENV{PERL_ANYEVENT_VERBOSE}. |
1016 | |
1014 | |
1017 | If you want to sprinkle loads of logging calls around your code, |
1015 | If you want to sprinkle loads of logging calls around your code, |
1018 | consider creating a logger callback with the "AnyEvent::Log::logger" |
1016 | consider creating a logger callback with the "AnyEvent::Log::logger" |
1019 | function, which can reduce typing, codesize and can reduce the |
1017 | function, which can reduce typing, codesize and can reduce the |
1020 | logging overhead enourmously. |
1018 | logging overhead enourmously. |
… | |
… | |
1216 | This ensures that child processes will not see the "AE_" variables. |
1214 | This ensures that child processes will not see the "AE_" variables. |
1217 | |
1215 | |
1218 | The following environment variables are currently known to AnyEvent: |
1216 | The following environment variables are currently known to AnyEvent: |
1219 | |
1217 | |
1220 | "PERL_ANYEVENT_VERBOSE" |
1218 | "PERL_ANYEVENT_VERBOSE" |
1221 | By default, AnyEvent will be completely silent except in fatal |
1219 | By default, AnyEvent will log messages with loglevel 4 ("error") or |
1222 | conditions. You can set this environment variable to make AnyEvent |
1220 | higher (see AnyEvent::Log). You can set this environment variable to |
1223 | more talkative. If you want to do more than just set the global |
1221 | a numerical loglevel to make AnyEvent more (or less) talkative. |
|
|
1222 | |
|
|
1223 | If you want to do more than just set the global logging level you |
1224 | logging level you should have a look at "PERL_ANYEVENT_LOG", which |
1224 | should have a look at "PERL_ANYEVENT_LOG", which allows much more |
1225 | allows much more complex specifications. |
1225 | complex specifications. |
1226 | |
1226 | |
|
|
1227 | When set to 0 ("off"), then no messages whatsoever will be logged |
|
|
1228 | with everything else at defaults. |
|
|
1229 | |
1227 | When set to 5 or higher (warn), causes AnyEvent to warn about |
1230 | When set to 5 or higher ("warn"), AnyEvent warns about unexpected |
1228 | unexpected conditions, such as not being able to load the event |
1231 | conditions, such as not being able to load the event model specified |
1229 | model specified by "PERL_ANYEVENT_MODEL", or a guard callback |
1232 | by "PERL_ANYEVENT_MODEL", or a guard callback throwing an exception |
1230 | throwing an exception - this is the minimum recommended level. |
1233 | - this is the minimum recommended level for use during development. |
1231 | |
1234 | |
1232 | When set to 7 or higher (info), cause AnyEvent to report which event |
1235 | When set to 7 or higher (info), AnyEvent reports which event model |
1233 | model it chooses. |
1236 | it chooses. |
1234 | |
1237 | |
1235 | When set to 8 or higher (debug), then AnyEvent will report extra |
1238 | When set to 8 or higher (debug), then AnyEvent will report extra |
1236 | information on which optional modules it loads and how it implements |
1239 | information on which optional modules it loads and how it implements |
1237 | certain features. |
1240 | certain features. |
1238 | |
1241 | |
… | |
… | |
1250 | itself. |
1253 | itself. |
1251 | |
1254 | |
1252 | Note that specifying this environment variable causes the |
1255 | Note that specifying this environment variable causes the |
1253 | AnyEvent::Log module to be loaded, while "PERL_ANYEVENT_VERBOSE" |
1256 | AnyEvent::Log module to be loaded, while "PERL_ANYEVENT_VERBOSE" |
1254 | does not, so only using the latter saves a few hundred kB of memory |
1257 | does not, so only using the latter saves a few hundred kB of memory |
1255 | until the first message is being logged. |
1258 | unless a module explicitly needs the extra features of |
|
|
1259 | AnyEvent::Log. |
1256 | |
1260 | |
1257 | "PERL_ANYEVENT_STRICT" |
1261 | "PERL_ANYEVENT_STRICT" |
1258 | AnyEvent does not do much argument checking by default, as thorough |
1262 | AnyEvent does not do much argument checking by default, as thorough |
1259 | argument checking is very costly. Setting this variable to a true |
1263 | argument checking is very costly. Setting this variable to a true |
1260 | value will cause AnyEvent to load "AnyEvent::Strict" and then to |
1264 | value will cause AnyEvent to load "AnyEvent::Strict" and then to |
… | |
… | |
1267 | is definitely recommended to keep it off in production. Keeping |
1271 | is definitely recommended to keep it off in production. Keeping |
1268 | "PERL_ANYEVENT_STRICT=1" in your environment while developing |
1272 | "PERL_ANYEVENT_STRICT=1" in your environment while developing |
1269 | programs can be very useful, however. |
1273 | programs can be very useful, however. |
1270 | |
1274 | |
1271 | "PERL_ANYEVENT_DEBUG_SHELL" |
1275 | "PERL_ANYEVENT_DEBUG_SHELL" |
1272 | If this env variable is set, then its contents will be interpreted |
1276 | If this env variable is nonempty, then its contents will be |
1273 | by "AnyEvent::Socket::parse_hostport" (after replacing every |
1277 | interpreted by "AnyEvent::Socket::parse_hostport" and |
1274 | occurance of $$ by the process pid) and an "AnyEvent::Debug::shell" |
1278 | "AnyEvent::Debug::shell" (after replacing every occurance of $$ by |
1275 | is bound on that port. The shell object is saved in |
1279 | the process pid). The shell object is saved in |
1276 | $AnyEvent::Debug::SHELL. |
1280 | $AnyEvent::Debug::SHELL. |
1277 | |
1281 | |
1278 | This happens when the first watcher is created. |
1282 | This happens when the first watcher is created. |
1279 | |
1283 | |
1280 | For example, to bind a debug shell on a unix domain socket in |
1284 | For example, to bind a debug shell on a unix domain socket in |
1281 | /tmp/debug<pid>.sock, you could use this: |
1285 | /tmp/debug<pid>.sock, you could use this: |
1282 | |
1286 | |
1283 | PERL_ANYEVENT_DEBUG_SHELL=/tmp/debug\$\$.sock perlprog |
1287 | PERL_ANYEVENT_DEBUG_SHELL=/tmp/debug\$\$.sock perlprog |
|
|
1288 | # connect with e.g.: socat readline /tmp/debug123.sock |
1284 | |
1289 | |
|
|
1290 | Or to bind to tcp port 4545 on localhost: |
|
|
1291 | |
|
|
1292 | PERL_ANYEVENT_DEBUG_SHELL=127.0.0.1:4545 perlprog |
|
|
1293 | # connect with e.g.: telnet localhost 4545 |
|
|
1294 | |
1285 | Note that creating sockets in /tmp is very unsafe on multiuser |
1295 | Note that creating sockets in /tmp or on localhost is very unsafe on |
1286 | systems. |
1296 | multiuser systems. |
1287 | |
1297 | |
1288 | "PERL_ANYEVENT_DEBUG_WRAP" |
1298 | "PERL_ANYEVENT_DEBUG_WRAP" |
1289 | Can be set to 0, 1 or 2 and enables wrapping of all watchers for |
1299 | Can be set to 0, 1 or 2 and enables wrapping of all watchers for |
1290 | debugging purposes. See "AnyEvent::Debug::wrap" for details. |
1300 | debugging purposes. See "AnyEvent::Debug::wrap" for details. |
1291 | |
1301 | |
… | |
… | |
1306 | |
1316 | |
1307 | For example, to force the pure perl model (AnyEvent::Loop::Perl) you |
1317 | For example, to force the pure perl model (AnyEvent::Loop::Perl) you |
1308 | could start your program like this: |
1318 | could start your program like this: |
1309 | |
1319 | |
1310 | PERL_ANYEVENT_MODEL=Perl perl ... |
1320 | PERL_ANYEVENT_MODEL=Perl perl ... |
|
|
1321 | |
|
|
1322 | "PERL_ANYEVENT_IO_MODEL" |
|
|
1323 | The current file I/O model - see AnyEvent::IO for more info. |
|
|
1324 | |
|
|
1325 | At the moment, only "Perl" (small, pure-perl, synchronous) and |
|
|
1326 | "IOAIO" (truly asynchronous) are supported. The default is "IOAIO" |
|
|
1327 | if AnyEvent::AIO can be loaded, otherwise it is "Perl". |
1311 | |
1328 | |
1312 | "PERL_ANYEVENT_PROTOCOLS" |
1329 | "PERL_ANYEVENT_PROTOCOLS" |
1313 | Used by both AnyEvent::DNS and AnyEvent::Socket to determine |
1330 | Used by both AnyEvent::DNS and AnyEvent::Socket to determine |
1314 | preferences for IPv4 or IPv6. The default is unspecified (and might |
1331 | preferences for IPv4 or IPv6. The default is unspecified (and might |
1315 | change, or be the result of auto probing). |
1332 | change, or be the result of auto probing). |
… | |
… | |
1351 | |
1368 | |
1352 | "PERL_ANYEVENT_MAX_OUTSTANDING_DNS" |
1369 | "PERL_ANYEVENT_MAX_OUTSTANDING_DNS" |
1353 | The default value for the "max_outstanding" parameter for the |
1370 | The default value for the "max_outstanding" parameter for the |
1354 | default DNS resolver - this is the maximum number of parallel DNS |
1371 | default DNS resolver - this is the maximum number of parallel DNS |
1355 | requests that are sent to the DNS server. |
1372 | requests that are sent to the DNS server. |
|
|
1373 | |
|
|
1374 | "PERL_ANYEVENT_MAX_SIGNAL_LATENCY" |
|
|
1375 | Perl has inherently racy signal handling (you can basically choose |
|
|
1376 | between losing signals and memory corruption) - pure perl event |
|
|
1377 | loops (including "AnyEvent::Loop", when "Async::Interrupt" isn't |
|
|
1378 | available) therefore have to poll regularly to avoid losing signals. |
|
|
1379 | |
|
|
1380 | Some event loops are racy, but don't poll regularly, and some event |
|
|
1381 | loops are written in C but are still racy. For those event loops, |
|
|
1382 | AnyEvent installs a timer that regularly wakes up the event loop. |
|
|
1383 | |
|
|
1384 | By default, the interval for this timer is 10 seconds, but you can |
|
|
1385 | override this delay with this environment variable (or by setting |
|
|
1386 | the $AnyEvent::MAX_SIGNAL_LATENCY variable before creating signal |
|
|
1387 | watchers). |
|
|
1388 | |
|
|
1389 | Lower values increase CPU (and energy) usage, higher values can |
|
|
1390 | introduce long delays when reaping children or waiting for signals. |
|
|
1391 | |
|
|
1392 | The AnyEvent::Async module, if available, will be used to avoid this |
|
|
1393 | polling (with most event loops). |
1356 | |
1394 | |
1357 | "PERL_ANYEVENT_RESOLV_CONF" |
1395 | "PERL_ANYEVENT_RESOLV_CONF" |
1358 | The absolute path to a resolv.conf-style file to use instead of |
1396 | The absolute path to a resolv.conf-style file to use instead of |
1359 | /etc/resolv.conf (or the OS-specific configuration) in the default |
1397 | /etc/resolv.conf (or the OS-specific configuration) in the default |
1360 | resolver, or the empty string to select the default configuration. |
1398 | resolver, or the empty string to select the default configuration. |
… | |
… | |
2043 | AnyEvent::Impl::IOAsync, Anyevent::Impl::Irssi, AnyEvent::Impl::FLTK. |
2081 | AnyEvent::Impl::IOAsync, Anyevent::Impl::Irssi, AnyEvent::Impl::FLTK. |
2044 | |
2082 | |
2045 | Non-blocking handles, pipes, stream sockets, TCP clients and servers: |
2083 | Non-blocking handles, pipes, stream sockets, TCP clients and servers: |
2046 | AnyEvent::Handle, AnyEvent::Socket, AnyEvent::TLS. |
2084 | AnyEvent::Handle, AnyEvent::Socket, AnyEvent::TLS. |
2047 | |
2085 | |
|
|
2086 | Asynchronous File I/O: AnyEvent::IO. |
|
|
2087 | |
2048 | Asynchronous DNS: AnyEvent::DNS. |
2088 | Asynchronous DNS: AnyEvent::DNS. |
2049 | |
2089 | |
2050 | Thread support: Coro, Coro::AnyEvent, Coro::EV, Coro::Event. |
2090 | Thread support: Coro, Coro::AnyEvent, Coro::EV, Coro::Event. |
2051 | |
2091 | |
2052 | Nontrivial usage examples: AnyEvent::GPSD, AnyEvent::IRC, |
2092 | Nontrivial usage examples: AnyEvent::GPSD, AnyEvent::IRC, |
2053 | AnyEvent::HTTP. |
2093 | AnyEvent::HTTP. |
2054 | |
2094 | |
2055 | AUTHOR |
2095 | AUTHOR |
2056 | Marc Lehmann <schmorp@schmorp.de> |
2096 | Marc Lehmann <schmorp@schmorp.de> |
2057 | http://home.schmorp.de/ |
2097 | http://anyevent.schmorp.de |
2058 | |
2098 | |