Documentación oficial:
https://rvm.io/rvm/install
Para instalar rvm
\curl -sSL https://get.rvm.io | bash -s stable --ruby
Para ver que version de ruby tenemos instaldo:
➜ rvm list
rvm rubies
* ruby-2.2.4 [ x86_64 ]
# => - current
# =* - current && default
# * - default
Para instalar la version ruby 2.3
➜ rvm install ruby-2.3.0
rvm install ruby-2.3.0
Warning, new version of rvm available '1.27.0', you are using older version '1.26.11'.
You can disable this warning with: echo rvm_autoupdate_flag=0 >> ~/.rvmrc
You can enable auto-update with: echo rvm_autoupdate_flag=2 >> ~/.rvmrc
Searching for binary rubies, this might take some time.
No binary rubies available for: osx/10.11/x86_64/ruby-2.3.0.
Continuing with compilation. Please read 'rvm help mount' to get more information on binary rubies.
Checking requirements for osx.
Updating certificates in '/usr/local/etc/openssl/cert.pem'.
Requirements installation successful.
Installing Ruby from source to: /Users/fbarrios/.rvm/rubies/ruby-2.3.0, this may take a while depending on your cpu(s)...
ruby-2.3.0 - #downloading ruby-2.3.0, this may take a while depending on your connection...
% Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 13.5M 100 13.5M 0 0 116k 0 0:01:59 0:01:59 --:--:-- 257k
No checksum for downloaded archive, recording checksum in user configuration.
ruby-2.3.0 - #extracting ruby-2.3.0 to /Users/fbarrios/.rvm/src/ruby-2.3.0 - please wait
ruby-2.3.0 - #configuring - please wait
ruby-2.3.0 - #post-configuration - please wait
ruby-2.3.0 - #compiling - please wait
ruby-2.3.0 - #installing - please wait
ruby-2.3.0 - #making binaries executable - please wait
Installed rubygems 2.5.1 is newer than 2.4.8 provided with installed ruby, skipping installation, use --force to force installation.
ruby-2.3.0 - #gemset created /Users/fbarrios/.rvm/gems/ruby-2.3.0@global
ruby-2.3.0 - #importing gemset /Users/fbarrios/.rvm/gemsets/global.gems - please wait
ruby-2.3.0 - #generating global wrappers - please wait
ruby-2.3.0 - #gemset created /Users/fbarrios/.rvm/gems/ruby-2.3.0
ruby-2.3.0 - #importing gemsetfile /Users/fbarrios/.rvm/gemsets/default.gems evaluated to empty gem list
ruby-2.3.0 - #generating default wrappers - please wait
ruby-2.3.0 - #adjusting #shebangs for (gem irb erb ri rdoc testrb rake).
Install of ruby-2.3.0 - #complete
Ruby was built without documentation, to build it run: rvm docs generate-ri