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<!-- X-URL: http://step.polymtl.ca/~ldd/ext2fs/ext2fs_8.html -->
<!-- This HTML file has been created by texi2html 1.29
from ext2fs.texi on 3 August 1994 -->
<TITLE>Analysis of the Ext2fs structure - Directories</TITLE>
<P>Go to the <A HREF="ext2fs_7.html">previous</A>, <A HREF="ext2fs_9.html">next</A> section.<P>
<A NAME="IDX43"></A>
<H1><A NAME="SEC8" HREF="ext2fs_toc.html#SEC8">Directories</A></H1>
<A NAME="IDX44"></A>
<P>
Directories are special files that are used to create access path to
the files on disk. It is very important to understand that an inode may
have many access paths. Since the directories are essential part of the
file system, they have a specific structure. A directory file is a list
of entries of the following format:
<P>
<PRE>
struct ext2_dir_entry {
unsigned long inode;
unsigned short rec_len;
unsigned short name_len;
char name[EXT2_NAME_LEN];
};
</PRE>
<P>
<DL COMPACT>
<DT><CODE>inode</CODE>
<DD>points to the inode of the file.
<P>
<DT><CODE>rec_len</CODE>
<DD>length of the entry record.
<P>
<DT><CODE>name_len</CODE>
<DD>length of the file name.
<P>
<DT><CODE>name</CODE>
<DD>name of the file. This name may have a maximum length of
<CODE>EXT2_NAME_LEN</CODE> bytes (255 bytes as of version 0.5).
</DL>
<A NAME="IDX45"></A>
<A NAME="IDX46"></A>
<A NAME="IDX47"></A>
<P>
There is such an entry in the directory file for each file in the
directory. Since ext2fs is a Unix file system the first two entries in
the directory are file <SAMP>`.'</SAMP> and <SAMP>`..'</SAMP> which points to the
current directory and the parent directory respectively.
<P>
<P>Go to the <A HREF="ext2fs_7.html">previous</A>, <A HREF="ext2fs_9.html">next</A> section.<P>