Monks,

I had some files(~350) that I wanted to rename, and after a bit of work got them renamed, as I wanted. My question though is about how I could have done this more efficiently, so a bit of background, and then the code I used....

Like I said, I have 350 or so files, named from "1.png" to "350.png", and I simply wanted leading 0's on any base filename that had less than 3 numeric characters, if that makes sense, so "1.png" becomes "001.png". 

#!/usr/bin/perl -w
use strict;

opendir(THISDIR,"e:\\perl\\comics\\");
my @comics=readdir(THISDIR);
close(THISDIR);

foreach (reverse(@comics)) {
   my ($name,$ext)=split(/\./,$_);
   if ($name=~/\d{3}/) {
      print '.';
   } elsif ($name=~/\d{2}/) {
      my $old=$name;
      $name=~s/(\d{2})/0$1/;
      rename "$old\.$ext", "$name\.$ext";
   } elsif ($name=~/\d{1}/) {
      my $old=$name;
      $name=~s/(\d{1})/00$1/;
      rename "$old\.$ext", "$name\.$ext";
   }
}

[download]


The wisdom of the monks is appreciated.

update: I made the changes that I picked up, and for the moment, I have this. Thanks for the lessons, monks. 

#!/usr/bin/perl
use warnings;
use strict;

chdir('e:/perl/comics/');
my @comics = glob('*.png');

foreach(@comics) {
    my $oldname = $_;
    $_ =~ s/(\d+)/sprintf("%03d",$1)/e;
    rename($oldname,$_) unless $oldname eq $_;
}

[download]

In reply to Optimize file renaming. by omega_monk

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