Thanks for your replies, guys! 
I tried both porcelain and rambo, they both look really cool for running system
processes/shell commands, but the problem still persist:
iex(1)> Porcelain.shell("vi")
Vim: Warning: Output is not to a terminal
Vim: Warning: Input is not from a terminal
Anyway, thanks for the feedback about choosing the right tool for the right job.
Porting my software in Elixir has started just for learning purposes but ended
in an overcomplicated mission.
