MISSING FILE SYSTEM FEATURES

[protobits]

  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

[xiaoxiang781216]

chmod etc: https://github.com/apache/incubator-nuttx/pull/4153 utimes etc: https://github.com/apache/incubator-nuttx/pull/4100

[resyfer]

• syncfs() is not implemented by any of the present file systems in the code.