V1/man/man5/directory.5

        11/3/71                                                  DIRECTORY (V)


NAME              format of directories

SYNOPSIS

DESCRIPTION       A directory behaves exactly like an ordinary file, save
                  that no user may write into a directory. The fact that a
                  file is a directory is indicated by a bit in the flag word
                  of its i--node entry.

                  Directory entries are 10 bytes long. The first word is the
                  i--node of the file represented by the entry, if non--zero;
                  if zero, the entry is empty.

                  Bytes 2--9 represent the (8--character) file name, null
                  padded on the right. These bytes are not necessarily
                  cleared for empty slots.

                  By convention, the first two entries in each directory are
                  for "." and "..". The first is an entry for the directory
                  itself. The second is for the parent directory. The meaning
                  of ".." is modified for the root directory of the master
                  file system and for the root directories of removable file
                  systems. In the first case, there is no parent, and in the
                  second, the system does not permit off--device references
                  without a mount system call. Therefore in both cases ".."
                  has the same meaning as ".".




FILES

SEE ALSO          file system format

DIAGNOSTICS

BUGS

OWNER             ken, dmr