DUP_VARIABLE
if ((flags & DUP_VARIABLE) || new >= fdp->fd_nfiles) {
if ((flags & DUP_VARIABLE) == 0 && new != newfd) {
error = kern_dup(DUP_VARIABLE, uap->fd, 0, &fd);
error = kern_dup(DUP_VARIABLE | DUP_FCNTL, fd, newmin,
error = kern_dup(DUP_VARIABLE | DUP_CLOEXEC | DUP_FCNTL,
error = kern_dup(DUP_VARIABLE | DUP_CLOFORK | DUP_FCNTL,