erlangpidmessage-passingerl

How to manually send a message to a process which I just spawned?


How can I send a message to process with Erlang? I did start a process and the output shows me that the pid (process identifier) is <0.39.0>. My question is how can I send a message to this process (<0.39.0>) manually.


Solution

  • While list_to_pid/1 can indeed be used to construct a PID and use it to send messages its usage is discouraged:

    This BIF is intended for debugging and for use in the Erlang operating system. It should not be used in application programs.

    A better approach would be to save the PID when you start the process:

    1> P = spawn(fun() -> receive _ -> ok end end).
    <0.34.0>
    2> P!hi.
    hi