Working with BASH environment variables (simple commands for beginners)


You'll learn the following in this tutorial.

I have tried instructions below on Ubuntu Server but should work for all distributions running the BASH shell.

Display names and values of all environment variables

env

Assign value to an environment variable

TESTVAR=value

Example:

TESTVAR=/usr/local/sbin:/usr/local/bin

Command above assigns the value "/usr/local/sbin:/usr/local/bin" to the TESTVAR variable.

Print value of a particular environment variable

echo $<variable name>

Example:

echo $TESTVAR

Command above prints the value of BASH's TESTVAR variable.

Append value to an existing environment variable:

<variable name>=$<variable name>:<new value>

Example:

TESTVAR=$TESTVAR:/bin

Command above appends "/bin" to the value of BASH's TESTVAR variable.

Make the variable globally accessible:

export <variable name>

Example:

export TESTVAR

Delete an environment variable:

unset <variable name>

Example:

unset TESTVAR

Please feel free to use the comments form below if you have any questions or need more explanation on anything. I recommend thoroughy testing on a production-like test system first before moving to production. Use the icons below to share this tutorial with your friends.

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bash linux

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