To change the error level, enter the following command, where x
    is SUCCESS, WARNING, or ERROR:

    FTP> SET ERROR_LEVEL x

    o  If x is SUCCESS, then WARNING, ERROR, and FATAL cause FTP to
       exit.

    o  If x is WARNING, then ERROR and FATAL cause FTP to exit.

    o  If x is ERROR, then only FATAL causes FTP to exit.

    Fatal errors always cause FTP to exit.