extern void focus(Client *c); /* focus c, c may be NULL */
extern Client *getclient(Window w); /* return client of w */
extern Client *getctitle(Window w); /* return client of title window */
extern void focus(Client *c); /* focus c, c may be NULL */
extern Client *getclient(Window w); /* return client of w */
extern Client *getctitle(Window w); /* return client of title window */