# Class Nethttpd_engine.http_engine

    class http_engine : on_request_header:(http_request_header_notification -> unit) -> unit -> #http_engine_config -> Unix.file_descr -> Unixqueue.unix_event_system -> [unit] Uq_engines.engine

This engine processes the requests arriving on the file descriptor using the Unix event system. Whenever a new request header arrives, the function `on_request_header` is called back, and must handle the request.

Unless aborted using the `abort` method, this engine is always successful. Errors are logged, but not returned as result.

The file descriptor is closed after processing all HTTP requests and responses. It is also closed on error and when the engine is aborted.

An aborted engine does not try to clean up resources external to the engine, e.g. by calling the `on_error` functions. This is up to the user.