--- AnyEvent/README 2011/10/04 17:45:04 1.69 +++ AnyEvent/README 2013/08/21 08:40:28 1.71 @@ -264,7 +264,7 @@ my $w = AnyEvent->timer (after => 0.5, interval => 1, cb => sub { warn "timeout\n"; - }; + }); TIMING ISSUES There are two ways to handle timers: based on real time (relative, "fire @@ -421,7 +421,7 @@ will be delayed. The maximum time a signal might be delayed is 10 seconds by default, but can be overriden via $ENV{PERL_ANYEVENT_MAX_SIGNAL_LATENCY} or $AnyEvent::MAX_SIGNAL_LATENCY - - see the Ö section for details. + - see the "ENVIRONMENT VARIABLES" section for details. All these problems can be avoided by installing the optional Async::Interrupt module, which works with most event loops. It will not @@ -738,6 +738,10 @@ $cv->end; + ... + + my $results = $cv->recv; + This code fragment supposedly pings a number of hosts and calls "send" after results for all then have have been gathered - in any order. To achieve this, the code issues a call to "begin" when it @@ -776,10 +780,15 @@ Note that doing a blocking wait in a callback is not supported by any event loop, that is, recursive invocation of a blocking "->recv" - is not allowed, and the "recv" call will "croak" if such a condition - is detected. This condition can be slightly loosened by using - Coro::AnyEvent, which allows you to do a blocking "->recv" from any - thread that doesn't run the event loop itself. + is not allowed and the "recv" call will "croak" if such a condition + is detected. This requirement can be dropped by relying on + Coro::AnyEvent , which allows you to do a blocking "->recv" from any + thread that doesn't run the event loop itself. Coro::AnyEvent is + loaded automatically when Coro is used with AnyEvent, so code does + not need to do anything special to take advantage of that: any code + that would normally block your program because it calls "recv", be + executed in an "async" thread instead without blocking other + threads. Not all event models support a blocking wait - some die in that case (programs might want to do that to stay interactive), so *if you are @@ -1084,22 +1093,22 @@ non-exhaustive list), and the list is heavily biased towards modules of the AnyEvent author himself :) - AnyEvent::Util + AnyEvent::Util (part of the AnyEvent distribution) Contains various utility functions that replace often-used blocking functions such as "inet_aton" with event/callback-based versions. - AnyEvent::Socket + AnyEvent::Socket (part of the AnyEvent distribution) Provides various utility functions for (internet protocol) sockets, addresses and name resolution. Also functions to create non-blocking tcp connections or tcp servers, with IPv6 and SRV record support and more. - AnyEvent::Handle + AnyEvent::Handle (part of the AnyEvent distribution) Provide read and write buffers, manages watchers for reads and writes, supports raw and formatted I/O, I/O queued and fully transparent and non-blocking SSL/TLS (via AnyEvent::TLS). - AnyEvent::DNS + AnyEvent::DNS (part of the AnyEvent distribution) Provides rich asynchronous DNS resolver capabilities. AnyEvent::HTTP, AnyEvent::IRC, AnyEvent::XMPP, AnyEvent::GPSD, @@ -1108,7 +1117,7 @@ (for the curious, IGS is the International Go Server and FCP is the Freenet Client Protocol). - AnyEvent::AIO + AnyEvent::AIO (part of the AnyEvent distribution) Truly asynchronous (as opposed to non-blocking) I/O, should be in the toolbox of every event programmer. AnyEvent::AIO transparently fuses IO::AIO and AnyEvent together, giving AnyEvent access to @@ -1216,25 +1225,24 @@ The following environment variables are currently known to AnyEvent: "PERL_ANYEVENT_VERBOSE" - By default, AnyEvent will only log messages with loglevel 3 - ("critical") or higher (see AnyEvent::Log). You can set this - environment variable to a numerical loglevel to make AnyEvent more - (or less) talkative. + By default, AnyEvent will log messages with loglevel 4 ("error") or + higher (see AnyEvent::Log). You can set this environment variable to + a numerical loglevel to make AnyEvent more (or less) talkative. If you want to do more than just set the global logging level you should have a look at "PERL_ANYEVENT_LOG", which allows much more complex specifications. When set to 0 ("off"), then no messages whatsoever will be logged - with the default logging settings. + with everything else at defaults. - When set to 5 or higher ("warn"), causes AnyEvent to warn about - unexpected conditions, such as not being able to load the event - model specified by "PERL_ANYEVENT_MODEL", or a guard callback - throwing an exception - this is the minimum recommended level. + When set to 5 or higher ("warn"), AnyEvent warns about unexpected + conditions, such as not being able to load the event model specified + by "PERL_ANYEVENT_MODEL", or a guard callback throwing an exception + - this is the minimum recommended level for use during development. - When set to 7 or higher (info), cause AnyEvent to report which event - model it chooses. + When set to 7 or higher (info), AnyEvent reports which event model + it chooses. When set to 8 or higher (debug), then AnyEvent will report extra information on which optional modules it loads and how it implements @@ -1256,7 +1264,8 @@ Note that specifying this environment variable causes the AnyEvent::Log module to be loaded, while "PERL_ANYEVENT_VERBOSE" does not, so only using the latter saves a few hundred kB of memory - until the first message is being logged. + unless a module explicitly needs the extra features of + AnyEvent::Log. "PERL_ANYEVENT_STRICT" AnyEvent does not do much argument checking by default, as thorough @@ -1319,6 +1328,13 @@ PERL_ANYEVENT_MODEL=Perl perl ... + "PERL_ANYEVENT_IO_MODEL" + The current file I/O model - see AnyEvent::IO for more info. + + At the moment, only "Perl" (small, pure-perl, synchronous) and + "IOAIO" (truly asynchronous) are supported. The default is "IOAIO" + if AnyEvent::AIO can be loaded, otherwise it is "Perl". + "PERL_ANYEVENT_PROTOCOLS" Used by both AnyEvent::DNS and AnyEvent::Socket to determine preferences for IPv4 or IPv6. The default is unspecified (and might @@ -1996,6 +2012,15 @@ its own. The pure-perl event loop (AnyEvent::Loop) will additionally load it to try to use a monotonic clock for timing stability. + AnyEvent::AIO (and IO::AIO) + The default implementation of AnyEvent::IO is to do I/O + synchronously, stopping programs while they access the disk, which + is fine for a lot of programs. + + Installing AnyEvent::AIO (and its IO::AIO dependency) makes it + switch to a true asynchronous implementation, so event processing + can continue even while waiting for disk I/O. + FORK Most event libraries are not fork-safe. The ones who are usually are because they rely on inefficient but fork-safe "select" or "poll" calls @@ -2076,6 +2101,8 @@ Non-blocking handles, pipes, stream sockets, TCP clients and servers: AnyEvent::Handle, AnyEvent::Socket, AnyEvent::TLS. + Asynchronous File I/O: AnyEvent::IO. + Asynchronous DNS: AnyEvent::DNS. Thread support: Coro, Coro::AnyEvent, Coro::EV, Coro::Event. @@ -2085,5 +2112,5 @@ AUTHOR Marc Lehmann - http://home.schmorp.de/ + http://anyevent.schmorp.de