列出ruby版本
console:~$ rvm list
rvm rubies
ruby-2.0.0-p481 [ i686 ]
# => - current
# =* - current && default
# * - default
尝试使用特定版本的ruby
console:~$ rvm use 2.0.0
RVM is not a function, selecting rubies with 'rvm use ...' will not work.
You need to change your terminal emulator preferences to allow login shell.
Sometimes it is required to use `/bin/bash --login` as the command.
Please visit https://rvm.io/integration/gnome-terminal/ for a example.
当前回答
如果RVM安装了专用的ubuntu RVM安装程序https://github.com/rvm/ubuntu_rvm, RVM脚本的路径将不同于/usr/share/rvm/scripts/rvm.因此，要将它添加到你的.bashrc中，运行以下命令:
echo 'source "/usr/share/rvm/scripts/rvm"' >> ~/.bashrc
其他回答
对我来说，在Ubuntu(18.08)中，我在.bashrc中添加了下面的行，它可以工作。
source /home/username/.rvm/scripts/rvm
请加上这一行。
Usually this is caused by shell initialization files. Search for PATH=... entries.
You can also re-add RVM to your profile by running: rvm get stable --auto-dotfiles
To fix it temporarily in this shell session run: rvm use ruby-2.6.5
To ignore this error add "rvm_silence_path_mismatch_check_flag=1" to your "~/.rvmrc" file.
如果RVM安装了专用的ubuntu RVM安装程序https://github.com/rvm/ubuntu_rvm, RVM脚本的路径将不同于/usr/share/rvm/scripts/rvm.因此，要将它添加到你的.bashrc中，运行以下命令:
echo 'source "/usr/share/rvm/scripts/rvm"' >> ~/.bashrc
您的控制台不是作为登录shell运行的，因此不能访问rvm功能。如果你正在运行Ubuntu，你可以:
打开控制台 选择“Edit -> Profile Preferences” 选择页签:标题和命令 复选框“作为登录shell运行命令” 重启终端
输入bash——从终端登录。然后给rvm使用2.0.0
