我下载了 Mac OSx 的命令行工具。检查 git 版本。然后尝试安装rvm：
MacBook-Pro:~ Tom$ curl -L https://get.rvm.io | bash -s stable
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 185 100 185 0 0 97 0 0:00:01 0:00:01 --:--:-- 106
100 10648 100 10648 0 0 4164 0 0:00:02 0:00:02 --:--:-- 118k
Downloading RVM from wayneeseguin branch stable
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left …