__open_nc
if ((fd = __open_nc(dfile, oflag, mode)) == -1)
if ((fd = __open_nc(dfile, (oflag | O_EXCL), mode)) == -1) {
fd = __open_nc(dfile, oflag & ~O_CREAT, mode);
if ((fd = __open_nc(dfile, O_RDWR | O_CREAT | O_EXCL, 0666))
int __open_nc(const char *, int, mode_t);