Bash Check If String Is Empty Code Example


Example 1: bash if null or empty

if [ -z "$variable" ];   then echo "$variable is null";   else echo "$variable is not null"; fi

Example 2: bash check if variable is empty

if [ -z "$var" ] #return true if $var is unset

Example 3: bash script check empty string

if [ -z "$var" ] then       echo "\$var is empty" else       echo "\$var is NOT empty" fi

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