Question

I write one module, which has one loop function, the function will send udp packet forever. i debug the program in erlang console, I want to know how to close the UDP socket ?
or else erlang will always print the debug message in console. thanks!

start() ->
  {ok, Sock} = gen_udp:open(0, []),
  send(Sock).

send(Sock) ->
  gen_udp:send(Sock, "127.0.0.1", 3211, "hello world"),
  timer:sleep(5000),
  send(Sock). 

Answer 1

There are two things to be considered here

1. If the process is the owner of
   the socket.In that case you can
   directly use gen_udp:close(Sock).
2. If the process is not the owner of the socket then use
   gen_udp:controlling_process(Sock,Pid)
   where Pid is the process id of the
   new owner of the socket. Now you can
   use gen_udp:close(Sock) from this
   process. http://www.erlang.org/doc/man/gen_udp.html