Ever wonder why so many bright people are writing all those nifty X GUI, UI, drawing, and graphics libraries? Why not just link against -lX11 -lXext? Here's a partial answer. I found it in hacks/screenhack.h in JWZ's amazing xscreensaver distribution. The screenhack files are supposed to make writing a simple graphics hack bearable. But why does it have to be so hard?

/* Found in Don Hopkins' .plan file:
 *
 *   The color situation is a total flying circus.  The X approach to
 *   device independence is to treat everything like a MicroVax framebuffer
 *   on acid.  A truely portable X application is required to act like the
 *   persistent customer in the Monty Python ``Cheese Shop'' sketch.  Even
 *   the simplest applications must answer many difficult questions, like:
 *
 *   WHAT IS YOUR DISPLAY?
 *       display = XOpenDisplay("unix:0");
 *   WHAT IS YOUR ROOT?
 *       root = RootWindow(display, DefaultScreen(display));
 *   AND WHAT IS YOUR WINDOW?
 *       win = XCreateSimpleWindow(display, root, 0, 0, 256, 256, 1,
 *                                 BlackPixel(display, DefaultScreen(display)),
 *                                 WhitePixel(display, DefaultScreen(display)))
 *   OH ALL RIGHT, YOU CAN GO ON.
 *
 *   WHAT IS YOUR DISPLAY?
 *         display = XOpenDisplay("unix:0");
 *   WHAT IS YOUR COLORMAP?
 *         cmap = DefaultColormap(display, DefaultScreen(display));
 *   AND WHAT IS YOUR FAVORITE COLOR?
 *         favorite_color = 0; / * Black. * /
 *         / * Whoops! No, I mean: * /
 *         favorite_color = BlackPixel(display, DefaultScreen(display));
 *         / * AAAYYYYEEEEE!! (client dumps core & falls into the chasm) * /
 *
 *   WHAT IS YOUR DISPLAY?
 *         display = XOpenDisplay("unix:0");
 *   WHAT IS YOUR VISUAL?
 *         struct XVisualInfo vinfo;
 *         if (XMatchVisualInfo(display, DefaultScreen(display),
 *                              8, PseudoColor, &vinfo) != 0)
 *            visual = vinfo.visual;
 *   AND WHAT IS THE NET SPEED VELOCITY OF AN XConfigureWindow REQUEST?
 *         / * Is that a SubStructureRedirectMask or a ResizeRedirectMask? * /
 *   WHAT?! HOW AM I SUPPOSED TO KNOW THAT?
 *   AAAAUUUGGGHHH!!!! (server dumps core & falls into the chasm)
 */
This is a literal quote from the source file, which is (presumably) a literal quote from the quoted plan file. I'm considering this inclusion "fair use"; I've no idea how else I could possibly include this.