bash, I know that there are a few ways to check whether a given variable is defined and contains a value. However, I want to check whether a given variable exists in the environment, and not as simply a local variable. For example ...
VAR1=value1 # local variable export VAR2=value2 # environment variable if [[ some_sort_of_test_for_env_var VAR1 ]] then echo VAR1 is in the environment else echo VAR1 is not in the environment fi if [[ some_sort_of_test_for_env_var VAR2 ]] then echo VAR2 is in the environment else echo VAR2 is not in the environment fi
some_sort_of_test_for_env_var be defined so that the bash code above will cause the following two lines to be printed?
VAR1 is not in the environment VAR2 is in the environment
I know that I can define a shell function to run
env and do a
grep for the variable name, but I'm wondering if there is a more direct "bash-like" way to determine whether a given variable is in the environment and not just a local variable.
Thank you in advance.