How do I delete an exported environment variable?
LinuxEnvironment VariablesUnsetLinux Problem Overview
Before installing gnuplot, I set the environment variable GNUPLOT_DRIVER_DIR = /home/gnuplot/build/src. During the installation, something went wrong.
I want to remove the GNUPLOT_DRIVER_DIR environment variable. How can I achieve it?
Linux Solutions
Solution 1 - Linux
unset is the command you're looking for.
unset GNUPLOT_DRIVER_DIR
Solution 2 - Linux
Walkthrough of creating and deleting an environment variable in Bash:
Test if the DUALCASE variable exists (empty output):
env | grep DUALCASE
It does not, so create the variable and export it:
DUALCASE=1
export DUALCASE
Check if it is there:
env | grep DUALCASE
Output:
> DUALCASE=1
It is there. So get rid of it:
unset DUALCASE
Check if it's still there (empty output):
env | grep DUALCASE
The DUALCASE exported environment variable is deleted.
Extra commands to help clear your local and environment variables:
Unset all local variables back to default on login:
CAN="chuck norris"
set | grep CAN
Output:
> CAN='chuck norris'
env | grep CAN # Empty output
exec bash
set | grep CAN
env | grep CAN # Empty output
exec bash command cleared all the local variables, but not environment variables.
Unset all environment variables back to default on login:
export DOGE="so wow"
env | grep DOGE
Output:
> DOGE=so wow
env -i bash
env | grep DOGE # Empty output
env -i bash command cleared all the environment variables to default on login.
Solution 3 - Linux
The original question doesn't mention how the variable was set, but:
In C shell (csh/tcsh) there are two ways to set an environment variable:
set x = "something"setenv x "something"
The difference in the behaviour is that variables set with the setenv command are automatically exported to a subshell while variables set with set aren't.
To unset a variable set with set, use
unset x
To unset a variable set with setenv, use
unsetenv x
Note: in all the above, I assume that the variable name is 'x'.
Credits:
Solution 4 - Linux
This may also work.
export GNUPLOT_DRIVER_DIR=
Solution 5 - Linux
As mentioned in the above answers, unset GNUPLOT_DRIVER_DIR should work if you have used export to set the variable. If you have set it permanently in ~/.bashrc or ~/.zshrc then simply removing it from there will work.