public static String getEnvironmentVariables() {
    return "\n\t"
        + IoTDBConstant.IOTDB_HOME
        + "="
        + System.getProperty(IoTDBConstant.IOTDB_HOME, "null")
        + ";"
        + "\n\t"
        + IoTDBConstant.IOTDB_CONF
        + "="
        + System.getProperty(IoTDBConstant.IOTDB_CONF, "null")
        + ";"
        + "\n\t"
        + IoTDBConstant.IOTDB_DATA_HOME
        + "="
        + System.getProperty(IoTDBConstant.IOTDB_DATA_HOME, "null")
        + ";";
  }
if the folders are relative paths, add IOTDB_DATA_HOME as the path prefix
iotdb-core/datanode/src/main/java/org/apache/iotdb/db/conf/IoTDBConfig.java