VMS Help RTL Routines, SMG$, SMG$BEGIN_DISPLAY_UPDATE  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    The Begin Batching of Display Updates routine saves, or batches,
    all output to a virtual display until a matching call to SMG$END_
    DISPLAY_UPDATE is encountered.

    Format

      SMG$BEGIN_DISPLAY_UPDATE  display-id

1 - Returns

    OpenVMS usage:cond_value
    type:         longword (unsigned)
    access:       write only
    mechanism:    by value

2 - Argument

 display-id

    OpenVMS usage:identifier
    type:         longword (unsigned)
    access:       read only
    mechanism:    by reference

    Specifies the virtual display for which output is to be batched.
    The display-id argument is the address of an unsigned longword
    that contains the display identifier.

    The display identifier is returned by SMG$CREATE_VIRTUAL_DISPLAY.