関連ワード:  bash check if variable is empty or null    shell check if variable is empty or null    bash check if variable is empty or not set    bash check if variable is empty or not defined    bash check if variable is empty or not    bash script check if variable is empty or null    bash check if variable is not empty or null    bash check if variable is empty string or null    shell script check if variable is empty or null    bash check if variable is not empty string  
結果 : bash check if variable is empty or null