>># 
>># Copyright 1990, 1991 by the Massachusetts Institute of Technology and
>># UniSoft Group Limited.
>># 
>># Permission to use, copy, modify, distribute, and sell this software and
>># its documentation for any purpose is hereby granted without fee,
>># provided that the above copyright notice appear in all copies and that
>># both that copyright notice and this permission notice appear in
>># supporting documentation, and that the names of MIT and UniSoft not be
>># used in advertising or publicity pertaining to distribution of the
>># software without specific, written prior permission.  MIT and UniSoft
>># make no representations about the suitability of this software for any
>># purpose.  It is provided "as is" without express or implied warranty.
>># 
>># $XConsortium: stbg.m,v 1.6 92/06/11 16:17:32 rws Exp $
>># 
>>#      SCCS:  @(#)  EAll.mc Rel 1.5	    (3/12/92)
>>#      SCCS:  @(#)  EGC.mc Rel 1.5	    (10/25/91)
>>#
>>TITLE XSetBackground CH05
>>ASSERTION A XSetBackground-1
The XSetBackground function sets the background component
of the specified GC to the pixel value supplied in the
background argument.
>>STRATEGY
Create window.
Create  GC with LineStyle = LineDoubleDash, bg = BlackPixel , fg = WhitePixel, fn = GXcopy, LineWidth = 1
Draw a horizonal line (sufficiently long for even and odd dashes) 
Verify pixel at (1, 0) is bg with XGetImage and XGetPixel.
Set gc bg component to fg value using XSetBackground.
Redraw same line (should fill in the gaps exactly)
Verify pixel at (1, 0) is fg with XGetImage and XGetPixel.
>>ASSERTION B XSetBackground-2
When the server fails to allocate a required resource, then
a BadAlloc error occurs.
>>STRATEGY
Report UNTESTED
>>ASSERTION A XSetBackground-3
When the GC argument does not name a defined GC, then a
BadGC error occurs.
>>STRATEGY
Create a GC.
Set GC id to -1 using XTestSetGContextOfGC.
Call test function using bad GC as the GC argument.
Verify that a BadGC error occurs.
