Use `sw_vers` to get Mac OS version
Use `sw_vers` to get Mac OS version

ENV['_system_version'] was not set on my Mac (10.10.3)

ruboto/ruboto,ruboto/ruboto,lucasallan/ruboto,baberthal/ruboto,ruboto/ruboto,baberthal/ruboto,Jodell88/ruboto,baberthal/ruboto,lucasallan/ruboto,Jodell88/ruboto,lucasallan/ruboto,Jodell88/ruboto