VMS Help TN3270, Qualifiers, /PRINTER  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /PRINTER=file

    Optional. Default: TN3270PRINT.LIS.

    File that records your screen's contents when you use the PRINT
    function.

    Directs printer output to either a file or a spooled printer (not
    a physical printer or terminal).