/sys$common/syshlp/helplib.hlb CONVERT, /DOCUMENT, Qualifiers, /FORMAT  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /FORMAT=format-name

    Specifies the encoding format of the input or output file. The
    default input and output format is DDIF.

    Input converters bundled with the CDA Base Services and the
    default file extensions for the file formats they support are as
    follows:

    Input Format   File Extension

    DDIF           .DDIF
    DTIF           .DTIF
    TEXT           .TXT

    Output converters bundled with the CDA Base Services for
    OpenVMS DECwindows Motif and the default file extensions for the
    file formats they support are as follows:

    Output
    Format         File Extension

    DDIF           .DDIF
    DTIF           .DTIF
    TEXT           .TXT
    PS             .PS
    ANALYSIS       .CDA$ANALYSIS