XdbeSwapBuffers(3X11)

     NAME
          XdbeSwapBuffers - swaps front and back DBE buffers.

     SYNOPSIS
          #include <X11/extensions/Xdbe.h>

          Status XdbeSwapBuffers(
              Display      *dpy,
              XdbeSwapInfo *swap_info,
              int          num_windows)

     DESCRIPTION
          This function swaps the front and back buffers for a list of
          windows.  The argument num_windows specifies how many
          windows are to have their buffers swapped; it is the number
          of elements in the swap_info array.  The argument swap_info
          specifies the information needed per window to do the swap.

          The XdbeSwapInfo structure has the following fields:

               Window            swap_window
               XdbeSwapAction    swap_action

          swap_window specifies the window for which to swap buffers.
          swap_action specifies the swap action to use for this
          swap_window.

          swap_action determines what will happen to the new back
          buffer of the swap_window it is paired with in the list in
          addition to making the old back buffer become visible.  The
          defined actions are as follows:


          XdbeUndefined
               The contents of the new back buffer become undefined.
               This may be the most efficient action since it allows
               the implementation to discard the contents of the
               buffer if it needs to.

          XdbeBackground
               The unobscured region of the new back buffer will be
               tiled with the window background.  The background
               action allows devices to use a fast clear capability
               during a swap.

          XdbeUntouched
               The unobscured region of the new back buffer will be
               unmodified by the swap.

          XdbeCopied
               The unobscured region of the new back buffer will be
               the contents of the old back buffer
     ERRORS
          BadMatch
               A non-double-buffered window was specififed or a window
               was specified twice.

          BadWindow
               An invalid window was specified.

          BadValue
               An invalid swap action was specified.

     SEE ALSO
          DBE, XdbeAllocateBackBufferName(), XdbeBeginIdiom(),
          XdbeDeallocateBackBufferName(), XdbeEndIdiom(),
          XdbeFreeVisualInfo(), XdbeGetBackBufferAttributes(),
          XdbeGetVisualInfo(), XdbeQueryExtension().