Requiem.QUIC.Config.load_priv_key_from_pem_file

You're seeing just the function load_priv_key_from_pem_file, go back to Requiem.QUIC.Config module for more information.
Link to this function

load_priv_key_from_pem_file(ptr, file)

Specs

load_priv_key_from_pem_file(integer(), binary()) ::
  :ok | {:error, :system_error | :not_found}