The SET OUTPUT command defines where CDO sends the output from
    CDO during a session.

    If you specify a file with the SET OUTPUT command, CDO sends
    output to the default output location (SYS$OUTPUT) for your
    current process and to the specified file.

    If you specify SET OUTPUT without a file specification, CDO sends
    output only to the default output location.

    The SET OUTPUT command stays in effect until you change it with
    another SET OUTPUT command.