extern void focusnext(Arg *arg); /* focuses next visible client, arg is ignored */
extern void focusprev(Arg *arg); /* focuses previous visible client, arg is ignored */
extern Bool isvisible(Client *c); /* returns True if client is visible */
extern void focusnext(Arg *arg); /* focuses next visible client, arg is ignored */
extern void focusprev(Arg *arg); /* focuses previous visible client, arg is ignored */
extern Bool isvisible(Client *c); /* returns True if client is visible */