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    QueryOverscan -- Inquire about a standard overscan region. (V36)

    success = QueryOverscan( DisplayID, Rect, OScanType )
    D0                       A0         A1    D0

    LONG QueryOverscan( ULONG, struct Rectangle *, WORD );

    This function fills in a rectangle with one of the system
    overscan dimensions, scaled appropriately for the mode of
    the DisplayID it is passed.

    There are three types of system overscan values:
    OSCAN_TEXT: completely visible, by user preference.  Used
      for Workbench screen and screen dimensions STDSCREENWIDTH
      and STDSCREENHEIGHT.  Left/Top is always 0,0.
    OSCAN_STANDARD: just beyond visible bounds of monitor, by
      user preference.  Left/Top may be negative.
    OSCAN_MAX: The largest region we can display, AND display
      any smaller region (see note below).
    OSCAN_VIDEO: The absolute largest region that the graphics.library
      can display.  This region must be used as-is.

    DisplayID -- A 32-bit identifier for a display mode, as
      defined in graphics/displayinfo.h.

      NOTE: If you only intend to use one of the four standard
      overscan dimensions as is, and open your screen to exactly
      the DisplayClip dimensions, you can specify one of
      the OSCAN_ values in the ExtNewScreen tag SA_StdDClip,
      and specify STDSCREENWIDTH and STDSCREENHEIGHT as the
      dimensions to more easily open up an overscanned screen
      (or use no NewScreen in OpenScreenTagList() and accept
      the default standard screen dimensions).

    Rect -- pointer to a Rectangle structure which this function
      will fill out with its return values.  Note that to convert
      a rectangle to a screen "Height" you do (MaxY - MinY + 1), and
      similarly for "Width."  The rectangle may be passed directly
      to OpenScreen() as a DisplayClip region (SA_DClip).

    0 (FALSE) if the MonitorSpec your NewScreen requests
    does not exist.  Non-zero (TRUE) if it does.

    Change in parameter V36.A17 might cause problems for some.

    OpenScreen(), Intuition V36 update documentation

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