Mapping, Moving & Uncovering Windows

Map windows using

XMapWindow(display,w)      
XMapSubwindows(display,w)  
XUnmapWindow(display,w)    
XUnmapSubwindows(display,w)

There are also a few fairly self-explanatory calls which can be used to move the windows around and shuffle them to the top and bottom of the pile like papers on a desk. The window manager may well interfere with your intentions, though - it's up to the user where top-level windows are, and which is on top.

XChangeWindowAttributes(display,w,valuemask,attributes)
    XSetWindowAttributes *attributes; 

XConfigureWindow(display,w, x, y, valuemask, values)
    unsigned int valuemask    /*  to select relevant fields of value   */
    XWindowChanges *values;    /* contains new details      */

XResizeWindow(display,w,width,height);
XMoveResizeWindow(display,w,x,y,width,height);
XSetWindowBorderWidth(display,w,width);
XRaiseWindow(display,w)       /* raise the window to the front */
XLowerWindow(display,w)       /* lower window to the back      */
XMoveWindow(display,w, x, y)  /* move and raise w   */
XCirculateSubwindows(display,w,direction);
                              /* direction is RaiseLowest or LowerHighest*/
XCirculateSubwindowsUp(display,w)      /* raises the lowest mapped child */
XCirculateSubwindowsDown(display,w)    /* lowers the highest mapped child*/