Why Is :fs.start_link/2 Undefined? - interop

Question

I'm attempting to use the fs library with Elixir. Elixir 1.2.5 and fs 0.9.2 on Windows 10. I've added fs to my dependencies in my mix.exs and it seems to be there (see below) but for some reason I keep getting an error trying to run :fs.start_link/2
I start iex -S mix and everything loads fine. I then try this: :fs.known_events() which returns: [:created, :modified, :removed, :renamed, :undefined] which is why I'm assuming that fs is getting loaded correctly.
But when I try :fs.start_link(:fs_watcher, "/users/ocaten~1") I get ** (UndefinedFunctionError) undefined function :fs.start_link/2 I tried :fs.start_link(:fs_watcher, '/users/ocaten~1') as well (char list vs. string) and get the same error. I checked the source of fs and there's definitely a start_link/2 function and it's exported so I'm really stumped by this.
Any suggestions as to how I might proceed?

Answer 1

It looks like :fs.start_link/2 was added on 11 Nov 2015 while version 0.9.2 was released on 23 Apr 2015. There is no release on hex.pm after 0.9.2 so you'll have to depend on the Github version if you want to use :fs.start_link/2:
mix.exs:
defp deps do
[{:fs, git: "https://github.com/synrc/fs"}]
end
Test:
iex(1)> :fs.start_link(:fs_watcher, "/tmp")
{:ok, #PID<0.168.0>}