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<font face="Helvetica, Arial, sans-serif">What is a hard link?
--> <a href="http://www.linfo.org/hard_link.html">http://www.linfo.org/hard_link.html</a><br>
<br>
Because of the nature of hard links, there's no way to know which
hard link existed first or which one is to be considered the
"original" file, because they point to the same underlying storage
which has only one lastmod/atime/mtime timestamp set.<br>
<br>
As such, the official rule on the matter is that the
asciibetically-first fully-qualified file name will be considered
the original, while the other hard links should be considered, as
already stated in the rules, "files already deduped". The reason
for this is strictly for output and reporting consistencies. (We
need this to maintain a standard baseline output format, which
I'll set forth in another email coming soon).<br>
<br>
</font>
<h3><font face="Helvetica, Arial, sans-serif">SCENARIO:</font><br>
</h3>
<font face="Helvetica, Arial, sans-serif">The three files below have
identical content:<br>
/foo/bar/baz.txt -> ( inode 12345 )<br>
/foo/car/daz.txt -> ( inode 12345 )<br>
/foo/far/gaz.txt -> ( inode 67890 )<br>
<br>
</font>
<h3><font face="Helvetica, Arial, sans-serif">OUTCOME:</font><br>
</h3>
<font face="Helvetica, Arial, sans-serif">/foo/far/gaz.txt should be
reported as a duplicate of /foo/bar/baz.txt because
/foo/bar/baz.txt comes before /foo/car/daz.txt in a sort and
because /foo/car/daz.txt is a hard link.<br>
<br>
</font>
<h3><font face="Helvetica, Arial, sans-serif">CODE:</font><br>
</h3>
<font face="Helvetica, Arial, sans-serif">I'm doing it like this.
This is just an unoptimized example. TIMTOWTDI.</font>
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<blockquote><big><tt># this will automatically throw out all but one
hardlink, with the only surviving</tt><tt><br>
</tt><tt># file name being the first asciibetically-sorted entry<br>
<br>
</tt><tt></tt><tt>$dev_inodes{ join '', ( stat $_ )[0,1] } = $_<br>
for reverse sort @group_of_same_size_files_by_name;</tt><tt><br>
</tt><tt><br>
</tt><tt>next if scalar keys %dev_inodes == 1; # don't keep
working if there's nothing to compare</tt><tt><br>
</tt><tt><br>
</tt><tt>for my file ( values %dev_inodes )</tt><tt><br>
</tt><tt>{</tt><tt><br>
</tt><tt> do stuff to figure out which of the same-size files
are duplicates...</tt><tt><br>
</tt><tt>}</tt><tt><br>
</tt></big></blockquote>
<font face="Helvetica, Arial, sans-serif"><br>
--Tommy Butler</font><br>
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