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 allocations of color should be made out of this colormap.

Both return the depth (number of planes) of the default root window for the specified screen.

Other depths may also be supported on this screen (see XMatchVisualInfo).

To determine the number of depths that are available on a given screen, use XListDepths.

The XListDepths function returns the array of depths that are available on the specified screen.

If the specified screen_number is valid and sufficient memory for the array can be allocated, XListDepths sets count_return to the number of available depths. Otherwise, it does not set count_return and returns NULL. To release the memory allocated for the array of depths, use XFree.

Both return the default graphics context for the root window of the specified screen. This GC is created for the convenience of simple applications and contains the default GC components with the foreground and background pixel values initialized to the black and white pixels for the