Permission flags are still limited. Linux reads vfat and fat32 partitions by mounting with type vfat . This is the native fs of Win-NT but as complete information is not available there is limited support for other OSes. These take a radically different approach to file updates by logging modifications for files in a log and later at some time checkpointing the logs. Reading is roughly as fast as traditional file systems that always update the files directly.
Writing is much faster as only updates are appended to a log.
All this is transparent to the user. It is in reliability and particularly in checking file system integrity that these file systems really shine. Since the data before last checkpointing is known to be good only the log has to be checked, and this is much faster than for traditional file systems. Note that while logging filesystems keep track of changes made to both data and inodes, journaling filesystems keep track only of inode changes. Linux has quite a choice in such file systems but none are yet in production quality.