A Simple Process

Here’s a module that defines a function we’d like to run as a separate process.

spawn/spawn-basic.ex
 
defmodule​ SpawnBasic ​do
 
def​ greet ​do
 
IO.puts ​"Hello"
 
end
 
end

Yup, that’s it. There’s nothing special—it’s just regular code.

Let’s fire up iex and play:

 
iex>​ c(​"spawn-basic.ex"​)
 
[SpawnBasic]

First let’s call it as a regular function:

 
iex>​ SpawnBasic.greet
 
Hello
 
:ok

Now let’s run it in a separate process:

 
iex>​ spawn(SpawnBasic, :greet, [])
 
Hello
 
#PID<0.42.0>

The spawn function kicks off a new process. It comes in many forms, but the two simplest ones let you run an anonymous function and run a named function in a module, passing a list of arguments. (We used the latter here.)

The spawn

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