The Create Display Scrolling Region routine creates a virtual
    scrolling region in a virtual display.

    Format

      SMG$SET_DISPLAY_SCROLL_REGION  display-id [,start-row]

                                     [,end-row]

1  –  Returns

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

2  –  Arguments

 display-id

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

    Specifies the virtual display in which scrolling takes place. 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.

 start-row

    OpenVMS usage:longword_signed
    type:         longword (signed)
    access:       read only
    mechanism:    by reference

    Specifies the first line of the virtual scrolling region. The
    start-row argument is the address of a signed longword that
    contains the starting line number. If omitted, the first line
    of the display is used.

 end-row

    OpenVMS usage:longword_signed
    type:         longword (signed)
    access:       read only
    mechanism:    by reference

    Specifies the last line of the virtual scrolling region. The end-
    row argument is the address of a signed longword that contains
    the ending line number. If omitted, the last line of the virtual
    display is used.