Basic information about a display can be obtained by calling the Release 2 graphics function GetDisplayInfoData(). You also call this function during the set up of a ViewPort. result = ULONG GetDisplayInfoData( DisplayInfoHandle handle, UBYTE *buf, ULONG size, ULONG tagID, ULONG modeID ) Set the handle argument to the DisplayInfoHandle returned by a previous call to FindDisplayInfo(). This function will also accept a 32-bit ModeID directly as an argument. The handle argument should be set to NULL in that case. The buf argument points to a destination buffer you have set up to hold the information about the properties of the display. The size argument gives the size of the buffer which depends on the type of inquiry you make. The tagID argument specifies the type information you want to know about and may be set as follows: DTAG_DISP Returns display properties and availability information (the buffer should be set to the size of a DisplayInfo structure). DTAG_DIMS Returns default dimensions and overscan information (the buffer should be set to the size of a DimensionInfo structure). DTAG_MNTR Returns monitor type, view position, scan rate, and compatibility (the buffer should be set to the size of a MonitorInfo structure). DTAG_NAME Returns the user friendly name for this mode (the buffer should be set to the size of a NameInfo structure). If the call succeeds, result is positive and reports the number of bytes actually transferred to the buffer. If the call fails (no information for the ModeID was available), result is zero.
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