opensolaris man page for dir

dir_ufs(4)							   File Formats 							dir_ufs(4)

NAME
       dir_ufs, dir - format of ufs directories

SYNOPSIS
       #include <sys/param.h>

       #include <sys/types.h>

       #include <sys/fs/ufs_fsdir.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, for example, 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 entries 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			 DEV_BSIZE
	 #define MAXNAMLEN			 256
	 struct direct {
		 ulong_t  d_ino;		 /* inode number of entry */
		 ushort_t d_reclen;		 /* length of this record */
		 ushort_t d_namlen;		 /* length of string in d_name */
		 char	  d_name[MAXNAMLEN + 1]; /* maximum name length */
	 };

ATTRIBUTES
       See attributes(5) for a description of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Unstable			   |
       +-----------------------------+-----------------------------+

SEE ALSO
       attributes(5), ufs(7FS)

SunOS 5.11							    16 Apr 2003 							dir_ufs(4)