What is “procmail” Package?

Autonomous mail processor
For more details: http://www.procmail.org

Installation

• Open Terminal by pressing command+space then type terminal and hit Enter key.
• Install homebrew first.

  ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)" < /dev/null 2> /dev/null

• Install procmail.

  brew install procmail

Now, use procmail!