MISSING FILE SYSTEM FEATURES

```
Description: Implement missing file system features:

chmod() is probably not relevant since file modes are not
currently supported.

File privileges would also be good to support. But this is
really a small part of a much larger feature. NuttX has no
user IDs, there are no groups, there are no privileges
associated with either. User's don't need credentials.
This is really a system wide issues of which chmod is only
a small part.

User privileges never seemed important to me since NuttX is
intended for deeply embedded environments where there are
not multiple users with varying levels of trust.

link, unlink, softlink, readlink - For symbolic links. Only
the ROMFS file system currently supports hard and soft links,
so this is not too important. The top-level, pseudo-file
system supports soft links.

File locking

Special files - NuttX support special files only in the top-
level pseudo file system. Unix systems support many
different special files via mknod(). This would be
important only if it is an objective of NuttX to become a
true Unix OS. Again only supported by ROMFS.

True inodes - Standard Unix inodes. Currently only supported
by ROMFs.

File times, for example as set by utimes().

The primary obstacle to all these is that each would require
changes to all existing file systems. That number is pretty
large. The number of file system implementations that would
need to be reviewed and modified As of this writing this
would include binfs, fat, hostfs, nfs, nxffs, procfs, romfs,
tmpfs, unionfs, plus pseduo-file system support.

Status: Open
Priority: Low
```