How to set up environment variable properly?

Question

I opened the /etc/environment and added the line ANDROID_SDK_HOME="/home/tom/android-sdk" but I tried echo $ANDROID_SDK_HOME but displayed nothing. I have JAVA_HOME in the same /etc/environment but its working. Please help me fix the problem. Thanks in advance.

Solution 1

Environment variables can be defined permanently by editing the .profile file in your home directory. Here's how:

Edit your .profile file with a command like gedit ~/.profile. Append this to the end of the file:

export ANDROID_SDK_HOME=/home/tom/android-sdk

You can source .profile to make it apply right away. Each time you restart your system, the .profile file is loaded, restoring this setting.

Solution 2

Its not recommended to use .profile file anymore to store user specific environment variables.

Use ~/.pam_environment file instead.

See: https://help.ubuntu.com/community/EnvironmentVariables