`sig
val accesslog : string -> unit
val errlog : string -> unit
val warning : string -> unit
val debug : (unit -> string) -> unit
val debug2 : string -> unit
val debug_noel : (unit -> string) -> unit
val debug_noel2 : string -> unit
val console : (unit -> string) -> unit
val console2 : string -> unit
val unexpected_exception : exn -> string -> unit
val error_log_path : unit -> string
val open_files :
?user:string option -> ?group:string option -> unit -> unit Lwt.t
val bip : int -> unit
end`