Class Uq_lwt.lwt_backend

Adapter for turning an Ocamlnet event_system into an Lwt Lwt_engine.t.

Use it like:

       class lwt_engine esys =
       object
         inherit Lwt_engine.abstract
         inherit Uq_lwt.lwt_backend esys
       end
    

(We've intentionally left out this definition to avoid any build dependency on Lwt. Also note that Lwt_engine is in the package lwt.unix.)

Now, activate this Lwt engine (event loop):

      Lwt_engine.set (new lwt_engine esys)
    

Note that Lwt can only deal with one event loop at a time, and the new event loop will be used for all Lwt code.

It is, unfortunately, necessary that you use the Lwt main loop (Lwt_main.run or Lwt_unix.run), because otherwise some hook functions are never executed (and execution will hang).

For an example, see tests/equeue/manual/relay.ml in the distribution tarball.

Netplex users: If you want to use lwt_engine for driving the event loop of the container, you can do so by overriding the processor hooks container_event_system and container_run, e.g.

    method container_event_system () =
      let esys = Unixqueue.create_unix_event_system() in
      Lwt_engine.set (new lwt_engine esys);
      esys

    method container_run esys =
      Lwt_main.run <something>
    

The Lwt thread <something> must at least run until the container is shut down. You can catch this moment by also defining the shutdown method.