for(i = nextvisible(c->mon->clients); i && i != c; i = nextvisible(i->next))
next_sel = i;
// failing that, find first visible window (besides c)
for(i = nextvisible(c->mon->clients); i && i != c; i = nextvisible(i->next))
next_sel = i;
// failing that, find first visible window (besides c)