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XClearArea(3)


NAME

   XClearArea, XClearWindow - clear area or window

SYNTAX

   int XClearArea(Display *display, Window w, int x, int y, unsigned
          width, unsigned height, Bool exposures);

   int XClearWindow(Display *display, Window w);

ARGUMENTS

   display   Specifies the connection to the X server.

   exposures Specifies a Boolean value that indicates if Expose events are
             to be generated.

   w         Specifies the window.

   width
   height    Specify the width and height, which are the dimensions of the
             rectangle.

   x
   y         Specify the x and y coordinates, which are relative to the
             origin of the window and specify the upper-left corner of the
             rectangle.

DESCRIPTION

   The XClearArea function paints a rectangular area in the specified
   window according to the specified dimensions with the window's
   background pixel or pixmap.  The subwindow-mode effectively is
   ClipByChildren.  If width is zero, it is replaced with the current
   width of the window minus x.  If height is zero, it is replaced with
   the current height of the window minus y.  If the window has a defined
   background tile, the rectangle clipped by any children is filled with
   this tile.  If the window has background None, the contents of the
   window are not changed.  In either case, if exposures is True, one or
   more Expose events are generated for regions of the rectangle that are
   either visible or are being retained in a backing store.  If you
   specify a window whose class is InputOnly, a BadMatch error results.

   XClearArea can generate BadMatch, BadValue, and BadWindow errors.

   The XClearWindow function clears the entire area in the specified
   window and is equivalent to XClearArea (display, w, 0, 0, 0, 0, False).
   If the window has a defined background tile, the rectangle is tiled
   with a plane-mask of all ones and GXcopy function.  If the window has
   background None, the contents of the window are not changed.  If you
   specify a window whose class is InputOnly, a BadMatch error results.

   XClearWindow can generate BadMatch and BadWindow errors.

DIAGNOSTICS

   BadMatch  An InputOnly window is used as a Drawable.

   BadValue  Some numeric value falls outside the range of values accepted
             by the request.  Unless a specific range is specified for an
             argument, the full range defined by the argument's type is
             accepted.  Any argument defined as a set of alternatives can
             generate this error.

   BadWindow A value for a Window argument does not name a defined Window.

SEE ALSO

   XCopyArea(3)
   Xlib - C Language X Interface



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