How to Print Environment Variables in Linux/Unix

printenv

This will print something like this:

...
rvm_bin_path=/Users/josephtyler/.rvm/bin
VIRTUALENVWRAPPER_SCRIPT=/usr/local/bin/virtualenvwrapper.sh
VIRTUALENVWRAPPER_PROJECT_FILENAME=.project
TERM_PROGRAM=Apple_Terminal
GEM_HOME=/Users/josephtyler/.rvm/gems/ruby-2.2.0
SHELL=/bin/bash
...

This is a list of environment variable keys and values. There is one key/value pair per line.

Still using printenv if you specify a name, then the value is printed (supposing it exists).

printenv RUBY_VERSION

will simply print:

ruby-2.2.0