How to set default Ruby version with RVM?
If you put the RVM source line in your bashrc (in order to ensure that non-interactive shells have access to RVM), you will need to source .bashrc from your .bash_profile with the following as the last lines in your .bash_profile
if [ -f "$HOME/.bashrc" ]; then
source $HOME/.bashrc
fi
This pre-supposes that you have
[[ -s "$HOME/.rvm/scripts/rvm" ]] && source "$HOME/.rvm/scripts/rvm"
in your $HOME/.bashrc. This is a good way to ensure that both interactive/login and non-interactive shells are able to find and load RVM correctly. Multi-User installs accomplish the same thing via the /etc/profile.d/rvm.sh file.
After that, you should have no problems defining a default Ruby to use via
rvm 1.9.2 --default
or
rvm use 1.9.2@mygemset --default
Its better to define a default gemset to use so as not to pollute your 'default' or 'global' gemsets.
If you are using non-interactive shells, be aware that they genereally operate in SH-compatibility mode which then requires you to set
BASH_ENV="$HOME/.bashrc"
in your $HOME/.profile in order you load RVM, or to set that within your script directly. The reason for this is that when bash is operating in SH mode it does not directly load .bash_profile or .bashrc as SH doesn't use those files, and bash is attempting to mimic the loading and execution process of the SH shell.
do an "rvm list" to see which Ruby versions you have installed.
then do this if you want to change the version only in one terminal session:
rvm use 1.8.7
if you want to select the default version for this user account, do this:
rvm use --default 1.9.2
See:
rvm use --help
See also this RailsCast:
http://railscasts.com/episodes/200-rails-3-beta-and-rvm
http://beginrescueend.com/
Late to party - anyway.
You did correctly set the default ruby version: rvm --default use 1.9.2
However, you need to update your Gemfile to the target ruby, because RVM references that file to select the working ruby version when you open terminal , that's why it reverted to the previous ruby version.