# Pastebin kNvPnS87
    The oflag argument may indicate that the file is to be created if it does not exist (by specifying the
     O_CREAT flag).  In this case, open() and openat() require an additional argument mode_t mode; the file
     is created with mode mode as described in chmod(2) and modified by the process' umask value (see
     umask(2)).