関連ワード:  check if environment variable is defined bash    check if env variable is defined bash    check if environment variable is set bash    check if env variable is set bash    check if environment variable is set shell    check if environment variable is not set bash    check if environment variable exists bash    check if environment variable exists shell    bash check if environment variable is set and not empty    bash check if environment variable is set to true  
結果 : check if environment variable is defined bash