mevent_add_flags
bc->bc_resize_event = mevent_add_flags(bc->bc_fd, EVF_VNODE,
struct mevent *mevent_add_flags(int fd, enum ev_type type, int fflags,
evp = mevent_add_flags(fd, EVF_VNODE, EVFF_ATTRIB, callback, cookie);
evp = mevent_add_flags(fd, EVF_VNODE, EVFF_ATTRIB, callback, cookie);