How to find whether or not a variable is empty in Bash

bash shell is-empty
Tree picture Tree · Jun 17, 2010 · Viewed 393.6k times · Source

How can I check if a variable is empty in Bash?

Answer

Jay picture Jay · Jun 17, 2010

In Bash at least the following command tests if $var is empty:

if [[ -z "$var" ]]; then
   # Do what you want
fi

The command man test is your friend.

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