Env vars on Ubuntu

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To set them, export VAR=1
To check them, printenv
To unset, unset VAR.

On Ubuntu, you can set vim ~/.pam_environment and then write:
JAVA_HOME=/usr/local/bin/jdk1.6.0_30
PATH DEFAULT=${PATH}:${JAVA_HOME}/bin

Or, you can go to ~/ .bashrc and write:
export JAVA_HOME="/usr/local/bin/jdk1.6.0_30"

export PATH=$PATH:$JAVA_HOME/bin

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