… | |
… | |
262 | |
262 | |
263 | Example 2: fire an event after 0.5 seconds, then roughly every second. |
263 | Example 2: fire an event after 0.5 seconds, then roughly every second. |
264 | |
264 | |
265 | my $w = AnyEvent->timer (after => 0.5, interval => 1, cb => sub { |
265 | my $w = AnyEvent->timer (after => 0.5, interval => 1, cb => sub { |
266 | warn "timeout\n"; |
266 | warn "timeout\n"; |
267 | }; |
267 | }); |
268 | |
268 | |
269 | TIMING ISSUES |
269 | TIMING ISSUES |
270 | There are two ways to handle timers: based on real time (relative, "fire |
270 | There are two ways to handle timers: based on real time (relative, "fire |
271 | in 10 seconds") and based on wallclock time (absolute, "fire at 12 |
271 | in 10 seconds") and based on wallclock time (absolute, "fire at 12 |
272 | o'clock"). |
272 | o'clock"). |
… | |
… | |
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 10 |
421 | will be delayed. The maximum time a signal might be delayed is 10 |
422 | seconds by default, but can be overriden via |
422 | seconds by default, but can be overriden via |
423 | $ENV{PERL_ANYEVENT_MAX_SIGNAL_LATENCY} or $AnyEvent::MAX_SIGNAL_LATENCY |
423 | $ENV{PERL_ANYEVENT_MAX_SIGNAL_LATENCY} or $AnyEvent::MAX_SIGNAL_LATENCY |
424 | - see the Ö<ENVIRONMENT VARIABLES> section for details. |
424 | - see the "ENVIRONMENT VARIABLES" section for details. |
425 | |
425 | |
426 | All these problems can be avoided by installing the optional |
426 | All these problems can be avoided by installing the optional |
427 | 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 |
428 | 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 |
429 | not with POE currently). For those, you just have to suffer the delays. |
429 | not with POE currently). For those, you just have to suffer the delays. |
… | |
… | |
736 | }; |
736 | }; |
737 | } |
737 | } |
738 | |
738 | |
739 | $cv->end; |
739 | $cv->end; |
740 | |
740 | |
|
|
741 | ... |
|
|
742 | |
|
|
743 | my $results = $cv->recv; |
|
|
744 | |
741 | This code fragment supposedly pings a number of hosts and calls |
745 | This code fragment supposedly pings a number of hosts and calls |
742 | "send" after results for all then have have been gathered - in any |
746 | "send" after results for all then have have been gathered - in any |
743 | order. To achieve this, the code issues a call to "begin" when it |
747 | order. To achieve this, the code issues a call to "begin" when it |
744 | starts each ping request and calls "end" when it has received some |
748 | starts each ping request and calls "end" when it has received some |
745 | result for it. Since "begin" and "end" only maintain a counter, the |
749 | result for it. Since "begin" and "end" only maintain a counter, the |
… | |
… | |
774 | In list context, all parameters passed to "send" will be returned, |
778 | In list context, all parameters passed to "send" will be returned, |
775 | in scalar context only the first one will be returned. |
779 | in scalar context only the first one will be returned. |
776 | |
780 | |
777 | Note that doing a blocking wait in a callback is not supported by |
781 | Note that doing a blocking wait in a callback is not supported by |
778 | any event loop, that is, recursive invocation of a blocking "->recv" |
782 | any event loop, that is, recursive invocation of a blocking "->recv" |
779 | is not allowed, and the "recv" call will "croak" if such a condition |
783 | is not allowed and the "recv" call will "croak" if such a condition |
780 | is detected. This condition can be slightly loosened by using |
784 | is detected. This requirement can be dropped by relying on |
781 | Coro::AnyEvent, which allows you to do a blocking "->recv" from any |
785 | Coro::AnyEvent , which allows you to do a blocking "->recv" from any |
782 | thread that doesn't run the event loop itself. |
786 | thread that doesn't run the event loop itself. Coro::AnyEvent is |
|
|
787 | loaded automatically when Coro is used with AnyEvent, so code does |
|
|
788 | not need to do anything special to take advantage of that: any code |
|
|
789 | that would normally block your program because it calls "recv", be |
|
|
790 | executed in an "async" thread instead without blocking other |
|
|
791 | threads. |
783 | |
792 | |
784 | Not all event models support a blocking wait - some die in that case |
793 | Not all event models support a blocking wait - some die in that case |
785 | (programs might want to do that to stay interactive), so *if you are |
794 | (programs might want to do that to stay interactive), so *if you are |
786 | using this from a module, never require a blocking wait*. Instead, |
795 | using this from a module, never require a blocking wait*. Instead, |
787 | let the caller decide whether the call will block or not (for |
796 | let the caller decide whether the call will block or not (for |
… | |
… | |
1082 | modules come as part of AnyEvent, the others are available via CPAN (see |
1091 | modules come as part of AnyEvent, the others are available via CPAN (see |
1083 | <http://search.cpan.org/search?m=module&q=anyevent%3A%3A*> for a longer |
1092 | <http://search.cpan.org/search?m=module&q=anyevent%3A%3A*> for a longer |
1084 | non-exhaustive list), and the list is heavily biased towards modules of |
1093 | non-exhaustive list), and the list is heavily biased towards modules of |
1085 | the AnyEvent author himself :) |
1094 | the AnyEvent author himself :) |
1086 | |
1095 | |
1087 | AnyEvent::Util |
1096 | AnyEvent::Util (part of the AnyEvent distribution) |
1088 | Contains various utility functions that replace often-used blocking |
1097 | Contains various utility functions that replace often-used blocking |
1089 | functions such as "inet_aton" with event/callback-based versions. |
1098 | functions such as "inet_aton" with event/callback-based versions. |
1090 | |
1099 | |
1091 | AnyEvent::Socket |
1100 | AnyEvent::Socket (part of the AnyEvent distribution) |
1092 | Provides various utility functions for (internet protocol) sockets, |
1101 | Provides various utility functions for (internet protocol) sockets, |
1093 | addresses and name resolution. Also functions to create non-blocking |
1102 | addresses and name resolution. Also functions to create non-blocking |
1094 | tcp connections or tcp servers, with IPv6 and SRV record support and |
1103 | tcp connections or tcp servers, with IPv6 and SRV record support and |
1095 | more. |
1104 | more. |
1096 | |
1105 | |
1097 | AnyEvent::Handle |
1106 | AnyEvent::Handle (part of the AnyEvent distribution) |
1098 | Provide read and write buffers, manages watchers for reads and |
1107 | Provide read and write buffers, manages watchers for reads and |
1099 | writes, supports raw and formatted I/O, I/O queued and fully |
1108 | writes, supports raw and formatted I/O, I/O queued and fully |
1100 | transparent and non-blocking SSL/TLS (via AnyEvent::TLS). |
1109 | transparent and non-blocking SSL/TLS (via AnyEvent::TLS). |
1101 | |
1110 | |
1102 | AnyEvent::DNS |
1111 | AnyEvent::DNS (part of the AnyEvent distribution) |
1103 | Provides rich asynchronous DNS resolver capabilities. |
1112 | Provides rich asynchronous DNS resolver capabilities. |
1104 | |
1113 | |
1105 | AnyEvent::HTTP, AnyEvent::IRC, AnyEvent::XMPP, AnyEvent::GPSD, |
1114 | AnyEvent::HTTP, AnyEvent::IRC, AnyEvent::XMPP, AnyEvent::GPSD, |
1106 | AnyEvent::IGS, AnyEvent::FCP |
1115 | AnyEvent::IGS, AnyEvent::FCP |
1107 | Implement event-based interfaces to the protocols of the same name |
1116 | Implement event-based interfaces to the protocols of the same name |
1108 | (for the curious, IGS is the International Go Server and FCP is the |
1117 | (for the curious, IGS is the International Go Server and FCP is the |
1109 | Freenet Client Protocol). |
1118 | Freenet Client Protocol). |
1110 | |
1119 | |
1111 | AnyEvent::AIO |
1120 | AnyEvent::AIO (part of the AnyEvent distribution) |
1112 | Truly asynchronous (as opposed to non-blocking) I/O, should be in |
1121 | Truly asynchronous (as opposed to non-blocking) I/O, should be in |
1113 | the toolbox of every event programmer. AnyEvent::AIO transparently |
1122 | the toolbox of every event programmer. AnyEvent::AIO transparently |
1114 | fuses IO::AIO and AnyEvent together, giving AnyEvent access to |
1123 | fuses IO::AIO and AnyEvent together, giving AnyEvent access to |
1115 | event-based file I/O, and much more. |
1124 | event-based file I/O, and much more. |
1116 | |
1125 | |
… | |
… | |
1214 | This ensures that child processes will not see the "AE_" variables. |
1223 | This ensures that child processes will not see the "AE_" variables. |
1215 | |
1224 | |
1216 | The following environment variables are currently known to AnyEvent: |
1225 | The following environment variables are currently known to AnyEvent: |
1217 | |
1226 | |
1218 | "PERL_ANYEVENT_VERBOSE" |
1227 | "PERL_ANYEVENT_VERBOSE" |
1219 | By default, AnyEvent will only log messages with loglevel 3 |
1228 | By default, AnyEvent will log messages with loglevel 4 ("error") or |
1220 | ("critical") or higher (see AnyEvent::Log). You can set this |
1229 | higher (see AnyEvent::Log). You can set this environment variable to |
1221 | environment variable to a numerical loglevel to make AnyEvent more |
1230 | a numerical loglevel to make AnyEvent more (or less) talkative. |
1222 | (or less) talkative. |
|
|
1223 | |
1231 | |
1224 | If you want to do more than just set the global logging level you |
1232 | If you want to do more than just set the global logging level you |
1225 | should have a look at "PERL_ANYEVENT_LOG", which allows much more |
1233 | should have a look at "PERL_ANYEVENT_LOG", which allows much more |
1226 | complex specifications. |
1234 | complex specifications. |
1227 | |
1235 | |
1228 | When set to 0 ("off"), then no messages whatsoever will be logged |
1236 | When set to 0 ("off"), then no messages whatsoever will be logged |
1229 | with the default logging settings. |
1237 | with everything else at defaults. |
1230 | |
1238 | |
1231 | When set to 5 or higher ("warn"), causes AnyEvent to warn about |
1239 | When set to 5 or higher ("warn"), AnyEvent warns about unexpected |
1232 | unexpected conditions, such as not being able to load the event |
1240 | conditions, such as not being able to load the event model specified |
1233 | model specified by "PERL_ANYEVENT_MODEL", or a guard callback |
1241 | by "PERL_ANYEVENT_MODEL", or a guard callback throwing an exception |
1234 | throwing an exception - this is the minimum recommended level. |
1242 | - this is the minimum recommended level for use during development. |
1235 | |
1243 | |
1236 | When set to 7 or higher (info), cause AnyEvent to report which event |
1244 | When set to 7 or higher (info), AnyEvent reports which event model |
1237 | model it chooses. |
1245 | it chooses. |
1238 | |
1246 | |
1239 | When set to 8 or higher (debug), then AnyEvent will report extra |
1247 | When set to 8 or higher (debug), then AnyEvent will report extra |
1240 | information on which optional modules it loads and how it implements |
1248 | information on which optional modules it loads and how it implements |
1241 | certain features. |
1249 | certain features. |
1242 | |
1250 | |
… | |
… | |
1254 | itself. |
1262 | itself. |
1255 | |
1263 | |
1256 | Note that specifying this environment variable causes the |
1264 | Note that specifying this environment variable causes the |
1257 | AnyEvent::Log module to be loaded, while "PERL_ANYEVENT_VERBOSE" |
1265 | AnyEvent::Log module to be loaded, while "PERL_ANYEVENT_VERBOSE" |
1258 | does not, so only using the latter saves a few hundred kB of memory |
1266 | does not, so only using the latter saves a few hundred kB of memory |
1259 | until the first message is being logged. |
1267 | unless a module explicitly needs the extra features of |
|
|
1268 | AnyEvent::Log. |
1260 | |
1269 | |
1261 | "PERL_ANYEVENT_STRICT" |
1270 | "PERL_ANYEVENT_STRICT" |
1262 | AnyEvent does not do much argument checking by default, as thorough |
1271 | AnyEvent does not do much argument checking by default, as thorough |
1263 | argument checking is very costly. Setting this variable to a true |
1272 | argument checking is very costly. Setting this variable to a true |
1264 | value will cause AnyEvent to load "AnyEvent::Strict" and then to |
1273 | value will cause AnyEvent to load "AnyEvent::Strict" and then to |
… | |
… | |
1316 | |
1325 | |
1317 | For example, to force the pure perl model (AnyEvent::Loop::Perl) you |
1326 | For example, to force the pure perl model (AnyEvent::Loop::Perl) you |
1318 | could start your program like this: |
1327 | could start your program like this: |
1319 | |
1328 | |
1320 | PERL_ANYEVENT_MODEL=Perl perl ... |
1329 | PERL_ANYEVENT_MODEL=Perl perl ... |
|
|
1330 | |
|
|
1331 | "PERL_ANYEVENT_IO_MODEL" |
|
|
1332 | The current file I/O model - see AnyEvent::IO for more info. |
|
|
1333 | |
|
|
1334 | At the moment, only "Perl" (small, pure-perl, synchronous) and |
|
|
1335 | "IOAIO" (truly asynchronous) are supported. The default is "IOAIO" |
|
|
1336 | if AnyEvent::AIO can be loaded, otherwise it is "Perl". |
1321 | |
1337 | |
1322 | "PERL_ANYEVENT_PROTOCOLS" |
1338 | "PERL_ANYEVENT_PROTOCOLS" |
1323 | Used by both AnyEvent::DNS and AnyEvent::Socket to determine |
1339 | Used by both AnyEvent::DNS and AnyEvent::Socket to determine |
1324 | preferences for IPv4 or IPv6. The default is unspecified (and might |
1340 | preferences for IPv4 or IPv6. The default is unspecified (and might |
1325 | change, or be the result of auto probing). |
1341 | change, or be the result of auto probing). |
… | |
… | |
1994 | This module is part of perl since release 5.008. It will be used |
2010 | This module is part of perl since release 5.008. It will be used |
1995 | when the chosen event library does not come with a timing source of |
2011 | when the chosen event library does not come with a timing source of |
1996 | its own. The pure-perl event loop (AnyEvent::Loop) will additionally |
2012 | its own. The pure-perl event loop (AnyEvent::Loop) will additionally |
1997 | load it to try to use a monotonic clock for timing stability. |
2013 | load it to try to use a monotonic clock for timing stability. |
1998 | |
2014 | |
|
|
2015 | AnyEvent::AIO (and IO::AIO) |
|
|
2016 | The default implementation of AnyEvent::IO is to do I/O |
|
|
2017 | synchronously, stopping programs while they access the disk, which |
|
|
2018 | is fine for a lot of programs. |
|
|
2019 | |
|
|
2020 | Installing AnyEvent::AIO (and its IO::AIO dependency) makes it |
|
|
2021 | switch to a true asynchronous implementation, so event processing |
|
|
2022 | can continue even while waiting for disk I/O. |
|
|
2023 | |
1999 | FORK |
2024 | FORK |
2000 | Most event libraries are not fork-safe. The ones who are usually are |
2025 | Most event libraries are not fork-safe. The ones who are usually are |
2001 | because they rely on inefficient but fork-safe "select" or "poll" calls |
2026 | because they rely on inefficient but fork-safe "select" or "poll" calls |
2002 | - higher performance APIs such as BSD's kqueue or the dreaded Linux |
2027 | - higher performance APIs such as BSD's kqueue or the dreaded Linux |
2003 | epoll are usually badly thought-out hacks that are incompatible with |
2028 | epoll are usually badly thought-out hacks that are incompatible with |
… | |
… | |
2074 | AnyEvent::Impl::IOAsync, Anyevent::Impl::Irssi, AnyEvent::Impl::FLTK. |
2099 | AnyEvent::Impl::IOAsync, Anyevent::Impl::Irssi, AnyEvent::Impl::FLTK. |
2075 | |
2100 | |
2076 | Non-blocking handles, pipes, stream sockets, TCP clients and servers: |
2101 | Non-blocking handles, pipes, stream sockets, TCP clients and servers: |
2077 | AnyEvent::Handle, AnyEvent::Socket, AnyEvent::TLS. |
2102 | AnyEvent::Handle, AnyEvent::Socket, AnyEvent::TLS. |
2078 | |
2103 | |
|
|
2104 | Asynchronous File I/O: AnyEvent::IO. |
|
|
2105 | |
2079 | Asynchronous DNS: AnyEvent::DNS. |
2106 | Asynchronous DNS: AnyEvent::DNS. |
2080 | |
2107 | |
2081 | Thread support: Coro, Coro::AnyEvent, Coro::EV, Coro::Event. |
2108 | Thread support: Coro, Coro::AnyEvent, Coro::EV, Coro::Event. |
2082 | |
2109 | |
2083 | Nontrivial usage examples: AnyEvent::GPSD, AnyEvent::IRC, |
2110 | Nontrivial usage examples: AnyEvent::GPSD, AnyEvent::IRC, |
2084 | AnyEvent::HTTP. |
2111 | AnyEvent::HTTP. |
2085 | |
2112 | |
2086 | AUTHOR |
2113 | AUTHOR |
2087 | Marc Lehmann <schmorp@schmorp.de> |
2114 | Marc Lehmann <schmorp@schmorp.de> |
2088 | http://home.schmorp.de/ |
2115 | http://anyevent.schmorp.de |
2089 | |
2116 | |