context

    OpenVMS usage:context
    type:         longword (unsigned)
    access:       modify
    mechanism:    by reference
    Message context information to be passed to message routines.
    The context argument is the address of a longword that contains
    message context information returned by MAIL$MESSAGE_BEGIN. If
    message processing ends successfully, the argument context is
    changed to 0.

 in_item_list

    OpenVMS usage:itmlst_3
    type:         longword (unsigned)
    access:       read only
    mechanism:    by reference
    Item list specifying options for the routine. This routine does
    not use the in_item_list argument.

 out_item_list

    OpenVMS usage:itmlst_3
    type:         longword
    access:       write only
    mechanism:    by reference
    Item list specifying the information you want the routine to
    return. This routine does not use the out_item_list argument.