update: I made the changes that I picked up, and for the moment, I have this. Thanks for the lessons, monks.
All in all looks fine. Only 
    $_ =~ s/(\d+)/sprintf("%03d",$1)/e;

[download]
One good point of using $_ is that so many built in functions and operators default to it, so that you can write 
    s/(\d+)/sprintf("%03d",$1)/e;

[download]
instead. Now, once you get used to Perl slang, this will become more intuitive and readable than the other way round. OTOH you may have chosen to do 
    (my $newname=$_) =~ s/(\d+)/sprintf("%03d",$1)/e;

[download]
instead. 
    rename($oldname,$_) unless $oldname eq $_;

[download]
Now, this is not strictly necessary: 
touch zizze; perl -le 'rename "zizze", "zizze" or die $!'

[download]
Of course it helps to avoid an unnecessary system call. But then again if it is a matter of a quick hack, I wouldn't do it. All in all I don't know if it is convenient efficiency-wise and wether it is or not depends strongly on the actual filenames. One could try to do a benchmark, but I'm not doing it now as my lazyness is currently overwhelming my hubris (BTW: see also Modules that significantly contribute to Laziness and Modules that significantly contribute to {Impatience,Hubris} - free ad! ;-)

In reply to Re: Optimize file renaming. by blazar
in thread Optimize file renaming. by omega_monk

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.