dir(4)                             (UFS)                             dir(4)


   NAME
         dir (ufs) - format of ufs directories

   SYNOPSIS
         #include <sys/param.h>
         #include <sys/types.h>
         #include <sys/fs/ufsfsdir.h>

   DESCRIPTION
         A directory consists of some number of blocks of DIRBLKSIZ bytes,
         where DIRBLKSIZ is chosen such that it can be transferred to disk in
         a single atomic operation (e.g. 512 bytes on most machines).

         Each DIRBLKSIZ-byte block contains some number of directory entry
         structures, which are of variable length.  Each directory entry has a
         struct direct at the front of it, containing its inode number, the
         length of the entry, and the length of the name contained in the
         entry.  These are followed by the name padded to a 4 byte boundary
         with null bytes.  All names are guaranteed null-terminated.  The
         maximum length of a name in a directory is MAXNAMLEN.

               #define DIRBLKSIZ DEVBSIZE
               #define MAXNAMLEN 256
               struct      direct {
                     ulong      dino;                  /* inode number of entry */
                     ushort     dreclen;         /* length of this record */
                     ushort     dnamlen;         /* length of string in dname */
                     char  dname[MAXNAMLEN + 1];  /* name must be no longer than this */
               };

   SEE ALSO
         ufs-specific fs(4)





















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