Hello,

You need escript for this job for example in your mix.exs you must pass

escript: [main_module: MyApp]

then in your module define something like this:

defmodule MyApp do
 def main(args) do
  args |> parse_args |> process
 end

def process([]) do
 IO.puts "No arguments given"
end

def process(options) do
 IO.puts "Hello #{options[:name]}"
end

 defp parse_args(args) do
  {options, _, _} = OptionParser.parse(args, switches: [name: :string])
  options
 end
end

finally from the command line:

mix escript.build
$ ./my_app --name=Elixir

Hello.

I was looking for a thread similar to my original post which I can no longer reply to (Google group got closed): https://groups.google.com/forum/#!topic/elixir-lang-talk/EbVag1bErEk

My original solution was indeed based on escript, but in order to enable “-mode embedded” for code preloading I had to switch away from it and over to building my software with distillery.

distillery builds you scripts to start your application like this: bin/myapp foreground

There is no escript involved.

And I found a solution for commandline arguments: http://erlang.org/doc/man/init.html#get_plain_arguments-0

I filtered, joined, and processed the results and I had all the commandline arguments I needed. Finally solved my problem with commandline arguments.

My final commandline looks like this: bin/myapp foreground --config "something". (You have other options to start the application, of course, like detached or with an attached console.) I then put the parsed results in my applications environment with Application.put_env(:myapp, <key, <value>) and retrieve them later when needed easily.

My idea was to avoid the mix escript.build step. Looking at mix tasks, it seems like I would have to start all dependencies manually - so maybe an escript is still the more elegant solution. Thank you for your example!