VMS Help MAIL Routines, MAIL$SEND_BEGIN, Output Item Codes  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 MAIL$_SEND_COPY_FORWARD

    When you specify the Boolean item code MAIL$_SEND_COPY_FORWARD,
    MAIL$SEND_BEGIN returns the value of the caller's copy forward
    flag as a longword value.

 MAIL$_SEND_COPY_SEND

    When you specify the Boolean item code MAIL$_SEND_COPY_SEND,
    MAIL$SEND_BEGIN returns the value of the caller's copy send flag
    as a longword value.

 MAIL$_SEND_COPY_REPLY

    When you specify the Boolean item code MAIL$_SEND_COPY_REPLY,
    MAIL$SEND_BEGIN returns the value of the caller's copy reply flag
    as a longword value.

 MAIL$_SEND_USER

    When you specify MAIL$_SEND_USER, MAIL$SEND_BEGIN returns the
    process owner's user name. The buffer address field of the item
    descriptor points to a buffer that receives a character string 0
    to 255 characters long.

    Specify a value from 0 to 255 in the buffer length field of the
    item descriptor.