cttyvp
struct vnode *ttyvp = cttyvp(curproc);
struct vnode *ttyvp = cttyvp(l->l_proc);
struct vnode *ttyvp = cttyvp(l->l_proc);
struct vnode *ttyvp = cttyvp(p);
struct vnode *ttyvp = cttyvp(l->l_proc);
struct vnode *ttyvp = cttyvp(curproc);
struct vnode *ttyvp = cttyvp(p);
if (cttyvp(curproc) == NULL)