uwt 0.0.2 · OCaml Package

type t

include module type of Handle with type t := t

val close : t -> Int_result.unit

Handles are closed automatically, if they are not longer referenced from the OCaml heap. Nevertheless, you should nearly always close them with close, because:

if they wrap a file descriptor, you will sooner or later run out of file descriptors. The OCaml garbage collector doesn't give any guarantee, when orphaned memory blocks are removed.

you might have registered some repeatedly called action (e.g. timeout, read_start,...), that prevent that all references get removed from the OCaml heap.

However, it's safe to write code in this manner:

let s = Uwt.Tcp.init () in
let c = Uwt.Tcp.init () in
Uwt.Tcp.nodelay s false;
Uwt.Tcp.simultaneous_accepts true;
if foobar () then (* no file descriptor yet assigned, no need to worry
                     about exceptions inside foobar,... *)
  Lwt.return_unit (* no need to close *)
else
  ...

If you want - for whatever reason - keep a file descriptor open for the whole lifetime of your process, remember to keep a reference to its handle.

val close_noerr : t -> unit

val close_wait : t -> unit Lwt.t

Prefer close or close_noerr to close_wait. close or close_noerr return immediately (there are no useful error messages, beside perhaps a notice, that you've already closed that handle).

close_wait is only useful, if you intend to wait until all concurrent write and read threads related to this handle are canceled.

val is_active : t -> bool

val ref' : t -> unit

val unref : t -> unit

val has_ref : t -> bool

include module type of Handle_ext with type t := t

val get_send_buffer_size : t -> Int_result.int

val get_send_buffer_size_exn : t -> int

val get_recv_buffer_size : t -> Int_result.int

val get_recv_buffer_size_exn : t -> int

val set_send_buffer_size : t -> int -> Int_result.unit

val set_send_buffer_size_exn : t -> int -> unit

val set_recv_buffer_size : t -> int -> Int_result.unit

val set_recv_buffer_size_exn : t -> int -> unit

include module type of Handle_fileno with type t := t

val fileno : t -> Unix.file_descr result

The usage of fileno is unsafe and strongly discouraged. But it's sometimes necessary, if you need to interact with third parties libraries. Rules:

You must still keep your orginal handle around. Otherwise uwt will close the handle ....

close the handle always with Handle.close, not Unix.close or any other function

Don't pass the file descriptor to functions like Pipe.openpipe or Poll.start

val fileno_exn : t -> Unix.file_descr

val to_handle : t -> Handle.t

val send_queue_size : t -> int

val send_queue_count : t -> int

val init : unit -> t

See comment to Pipe.init

val openudp : Unix.file_descr -> t result

See comment to Pipe.openpipe

val openudp_exn : Unix.file_descr -> t

type mode =

| Ipv6_only
| Reuse_addr

val bind : ?mode:mode list -> t -> addr:sockaddr -> unit -> Int_result.unit

parameter mode
default mode is the empty list

val bind_exn : ?mode:mode list -> t -> addr:sockaddr -> unit -> unit

val getsockname : t -> sockaddr result

val getsockname_exn : t -> sockaddr

type membership =

| Leave_group
| Join_group

val set_membership : 
  t ->
  multicast:string ->
  interface:string ->
  membership ->
  Int_result.unit

val set_membership_exn : 
  t ->
  multicast:string ->
  interface:string ->
  membership ->
  unit

val set_multicast_loop : t -> bool -> Int_result.unit

val set_multicast_loop_exn : t -> bool -> unit

val set_multicast_ttl : t -> int -> Int_result.unit

val set_multicast_ttl_exn : t -> int -> unit

val set_multicast_interface : t -> string -> Int_result.unit

val set_multicast_interface_exn : t -> string -> unit

val set_broadcast : t -> bool -> Int_result.unit

val set_broadcast_exn : t -> bool -> unit

val set_ttl : t -> int -> Int_result.unit

val set_ttl_exn : t -> int -> unit

val send : ?pos:int -> ?len:int -> buf:bytes -> t -> sockaddr -> unit Lwt.t

val send_ba : ?pos:int -> ?len:int -> buf:buf -> t -> sockaddr -> unit Lwt.t

val send_string : 
  ?pos:int ->
  ?len:int ->
  buf:string ->
  t ->
  sockaddr ->
  unit Lwt.t

val send_raw : ?pos:int -> ?len:int -> buf:bytes -> t -> sockaddr -> unit Lwt.t

See comment to Stream.write_raw

val send_raw_ba : 
  ?pos:int ->
  ?len:int ->
  buf:buf ->
  t ->
  sockaddr ->
  unit Lwt.t

val send_raw_string : 
  ?pos:int ->
  ?len:int ->
  buf:string ->
  t ->
  sockaddr ->
  unit Lwt.t

val try_send : 
  ?pos:int ->
  ?len:int ->
  buf:bytes ->
  t ->
  sockaddr ->
  Int_result.int

val try_send_ba : 
  ?pos:int ->
  ?len:int ->
  buf:buf ->
  t ->
  sockaddr ->
  Int_result.int

val try_send_string : 
  ?pos:int ->
  ?len:int ->
  buf:string ->
  t ->
  sockaddr ->
  Int_result.int

type recv_result =

| Data of Bytes.t * sockaddr option
| Partial_data of Bytes.t * sockaddr option
| Empty_from of sockaddr
| Transmission_error of error

The type definition will likely be changed. Don't use fragile pattern matching for it

val recv_start : t -> cb:(recv_result -> unit) -> Int_result.unit

val recv_start_exn : t -> cb:(recv_result -> unit) -> unit

val recv_stop : t -> Int_result.unit

val recv_stop_exn : t -> unit

type recv = {

recv_len : int;
is_partial : bool;
sockaddr : sockaddr option;

}

val recv : ?pos:int -> ?len:int -> buf:bytes -> t -> recv Lwt.t

Wrappers around recv_start and recv_stop for you convenience, no callback soup.

val recv_ba : ?pos:int -> ?len:int -> buf:buf -> t -> recv Lwt.t

package uwt