Here's a representative example from a larger script - I used the preprocess key in File::Find in an attempt to minimize matching operations and overhead inside of wanted's subroutine in the case of having to sift through many many files. 
#!/usr/bin/perl -w

use strict;
use Cwd;
use File::Find;


my $filespec   =  '*.pl *.txt';
my $dir        =  $ARGV[0] || getcwd(); 

find( { wanted => \&find_function, preprocess => \&globber }, $dir );

sub find_function {
   print $File::Find::name . $/;
}

sub globber {
   ( glob  "$filespec" );
}

[download]
The correct files in the first level directory get returned, but two additional things happen:

I must misunderstand what "preprocess" is for, but I am handing it the list it expects, I think..

So, does anyone know why the directory name gets returned in this case, and even better yet, a slick way to be able to specify file extensions from outside of "wanted" ?

Many thanks.. PS- I know it might be easier with File::Finder, and maybe other modules.. I was trying to stick with a standard module... many thanks..

Update: minor clarification of explanation

In reply to Behavior of File::Find's preprocess and glob by hsinclai

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.