DavidAlphaFox / everl

Async socket notifications for Erlang using libev

everl is an Erlang library for asynchronously generating socket notifications using libev. everl lets you watch file descriptors for events and sends your process a message whenever the socket state changes.

ABOUT

everl started out as a contribution to procket by Gregory Haskins (https://github.com/ghaskins) but it was so awesome I decided to move it into its own repository. The original patch is here:

https://github.com/msantos/procket/commit/1345e3b4a00ea10af24bd1cd9d52fa1b28de1b2a
https://github.com/msantos/procket/pull/2

libev was written by Marc Alexander Lehmann and is available from:

http://software.schmorp.de/pkg/libev.html

FEATURES

EXPORTS

create(FD, Flags) -> {ok, Handle} | {error, posix()}

    Types   FD = int()
            Flags = [Flag]
            Flag = read | write
            Handle = resource()

    Returns a handle for watching events on the file descriptor.

arm(Handle) -> ok

    Types   Handle = resource()

    Initiates notifications on the file descriptor. The watch handle
    must be re-armed after each notification is received.

    The process creating the handle will receive:

        {everl_watcher, FD, Event}

    Where

        FD is the file descriptor associated with the watch handle.

        Event is an integer:

            1 (READ): file descriptor is ready for reading
            2 (WRITE): file descriptor is ready for writing
            3 (RDWR): file descriptor is ready for reading and writing

disarm(Handle) -> ok

    Types   Handle = resource()

    Disable notifications for the file descriptor and close the
    watch handle.

USING IT

TESTING

make test

TODO

• Documentation and examples

• Support all of libev

• API changes