spawn

The basic mechanism for spawning new processes is with the auto-imported spawn/1 function:

iex> spawn fn -> 1 + 2 end
#PID<0.43.0>

spawn/1 takes a function which it will execute in another process.

Notice spawn/1 returns a PID (process identifier). At this point, the process you spawned is very likely dead. The spawned process will execute the given function and exit after the function is done:

iex> pid = spawn fn -> 1 + 2 end
#PID<0.44.0>
iex> Process.alive?(pid)
false

Note: you will likely get different process identifiers than the ones we are getting in this guide.

We can retrieve the PID of the current process by calling self/0:

iex> self()
#PID<0.41.0>
iex> Process.alive?(self())
true

Processes get much more interesting when we are able to send and receive messages.