Programming Elixir 1.2

When Processes Die

Who gets told when a process dies? By default, no one. Obviously the VM knows and can report it to the console, but your code will be oblivious unless you explicitly tell Elixir you want to get involved.

Here’s the default case: we spawn a function that uses the Erlang timer library to sleep for 500 ms. It then exits with a status of 99.

The code that spawns it sits in a receive. If it receives a message, it reports that fact; otherwise, after one second it lets us know that nothing happened.

spawn/link1.exs

defmodule Link1 do
  import :timer, only: [ sleep: 1 ]

  def sad_function do
    sleep 500
    exit(:boom)
  end
  def run do
    spawn(Link1, :sad_function, [])
    receive do
      msg ->
 IO.puts ...