Type of events. An event represent a callback registered to be called when some event occurs.

stop_event event stops the given event.

Event which does nothing when stopped.

iter block performs one iteration of the main loop. If block is true the function must block until one event becomes available, otherwise it should just check for available events and return immediately.

on_readable fd f calls f each time fd becomes readable.

on_readable fd f calls f each time fd becomes writable.

on_timer delay repeat f calls f one time after delay seconds. If repeat is true then f is called each delay seconds, otherwise it is called only one time.

Returns the number of events waiting for a file descriptor to become readable.

Returns the number of events waiting for a file descriptor to become writable.

Returns the number of registered timers.

Simulates activity on the given file descriptor.

Called internally by Lwt_unix.fork to make sure we don't get strange behaviour

forwards_signal signum is true if the engine will call Lwt_unix.handle_signal when signal signum occurs. In this case, Lwt will not install its own signal handler.

Normally, this just returns false, but when Lwt is used in combination with other IO libraries, this allows sharing e.g. the SIGCHLD handler.

Abstract class for engines.

Type of engines.

Engine based on libev. If not compiled with libev support, the creation of the class will raise Lwt_sys.Not_available.

Engine based on Unix.select.

Abstract class for engines based on a select-like function.

Abstract class for engines based on a poll-like function.

get () returns the engine currently in use.

set ?transfer ?destroy engine replaces the current engine by the given one.

If transfer is true (the default) all events from the current engine are transferred to the new one.

If destroy is true (the default) then the current engine is destroyed before being replaced.