DUP_CLOEXEC
if (flags & DUP_CLOEXEC)
if ((flags & DUP_CLOEXEC) != 0)
error = kern_dup(DUP_VARIABLE | DUP_CLOEXEC | DUP_FCNTL,
error = kern_dup(DUP_FIXED | DUP_CLOEXEC, fd, newmin,
((nflags & FD_CLOEXEC) != 0 ? DUP_CLOEXEC : 0) |