?timeout:float ->
?env:string array ->
?stderr:Lwt_process.redirection ->
Lwt_process.command ->
object
  method close : Unix.process_status Lwt.t
  method kill : int -> unit
  method pid : int
  method rusage : Lwt_unix.resource_usage Lwt.t
  method state : state
  method status : Unix.process_status Lwt.t
  method stdin : Lwt_io.output_channel
  method stdout : Lwt_io.input_channel
  method terminate : unit
end