if(dc.drawable != 0)
XFreePixmap(dpy, dc.drawable);
dc.drawable = XCreatePixmap(dpy, root, sw, bh, DefaultDepth(dpy, screen));
if(dc.drawable != 0)
XFreePixmap(dpy, dc.drawable);
dc.drawable = XCreatePixmap(dpy, root, sw, bh, DefaultDepth(dpy, screen));