Times out if can't read

timeout.ml

open Lwt
open Lwt_unix

let read fd =
  let maxlen = 1024 in
  let buf = Bytes.create maxlen in
  Lwt.catch
    (fun _ ->
      Lwt_log.info "reading" >>= fun () -> 
      Lwt.pick [
          Lwt_unix.timeout 1.0;
          Lwt_unix.read fd buf 0 maxlen
        ] >>= fun len ->
      if len = 0
      then Lwt_log.info "len = 0"
      else Lwt_log.info "got some bytes")
    (fun _ -> Lwt_log.info "got an error")

let connect fd =
  ignore(Lwt_unix.connect fd @@ ADDR_INET(Unix.inet_addr_of_string "172.217.195.113", 80));
  read fd >>= fun _ ->
  Lwt.return 0

let () =
  let fd = Lwt_unix.socket PF_INET SOCK_STREAM 0 in
  Pervasives.exit (Lwt_main.run (connect fd))

Compile with ocamlfind ocamlopt -package lwt.unix -package lwt_log -linkpkg -g timeout.ml -o timeout_test