-- "impatient.setl" (highly cautious version)

if (pump_fd := pump()) = -1 then
  -- Child (worker), deals with inherited client stream
  fd := open (val command_line(1), 'rw');           -- inherited stream
  while (line := getline fd) /= om loop
    printa (fd, #line);                   -- send line length to client
    print; flush(stdout);               -- make monitoring parent happy
  end loop;
  stop;                                                     -- all done

elseif pump_fd /= om then
  -- Parent (monitor) continues here
  loop                       -- cycle until EOF on pump_fd or timeout
    [ready] := select ([{pump_fd}], 15 * 60 * 1000);
    if pump_fd in ready then
      if getline pump_fd = om then
        stop;                    -- child exited normally, and so do we
      end if;
    else              -- timeout (nothing from pump_fd in 15 minutes)
      kill (pid (pump_fd));                -- send TERM signal to child
      stop;                    -- presume child exited, and do likewise
    end if;
  end loop;

else
  -- No child was created
  printa (stderr, 'pump() failed, dropping client');

end if;