How can I easily bulk rename files with Perl?

Question

I have a lot of files I'm trying to rename, I tried to make a regular expression to match them, but even that I got stuck on the files are named like:

File Name 01

File Name 100

File Name 02

File Name 03

etc, I would like to add a "0" (zero), behind any of file that are less than 100, like this:

File Name 001

File Name 100

File Name 002

File Name 003

The closest I got to so much as matching them was using this find -type d | sort -r | grep ' [1-9][0-9]$' however I could not figure out how to replace them. Thanks in advance for any help you can offer me. Im on CentOS if that is of any help, all this is being done via SSH.

Answer 1

I think mmv is your friend here.

Answer 2

find . -type d -print0 | xargs -0 rename 's/(\d+)/sprintf "%03d", $1/e'

or something like that, provided

1. You have GNU find and GNU xargs (for -print0 and -0)
2. You have the 'rename' utility that comes with perl
3. There's only one group of digits in the filename. If there's more than one, then you need to do something with the regex to make it only match the number you want to reformat.

Answer 3

Run two commands, in this order:

$ rename 's/File Name (\d)$/File Name 0$1/' *
$ rename 's/File Name (\d\d)$/File Name 0$1/' *

First one renames everything less than 10 and prepends a zero. The second one renames everything less than 100 and prepends a zero. The result should be three digits for all filenames.

Answer 4

you could do something using perl or ruby.

put all this files in the same directory

dirlisting = DIR.entries('.')

dirListing.each do |file| 
 num = file.match(/\d+$/).to_i
 if num < 100
   find the position where start the number, with index and inject the 0 there.
 end
end

Answer 5

Is this a one-time thing? If so, I'm going to suggest something that might seem to be a cop out by many programmers here:

Pipe the output of your command (find -type d | sort -r | grep ' [1-9][0-9]$') to a file and use an editor along with some global search/replace magic to create a script that does the renames.

Then throw away the script.

There's little fuss and little chance that you'll end up shooting yourself in the foot by having some attempt at a clever (but inadequately debugged) one-liner go off into the weeds on your files.

Answer 6

Does File Name represent a random string or are they actually called File Name (or some other fixed length string), if the text part is fixed length then this is easy.

Answer 7

perl -e 'foreach $f (glob("File\\ Name*")) { $nf = $f; $nf =~ s/(\d+)$/sprintf("%03d",$1)/e; print `mv \"$f\" \"$nf\"`;}'

A bit overkill maybe, but it does what is asked.

Answer 8

use strict;
use File::Copy;

my @files = glob 'File*Name*';

foreach my $filename (@files) {
    if ($filename =~ m`^.*File.*Name.*?(\d+)`) {
        my $number = $1;
        next if ($number > 99);
        rename $filename, sprintf("FileName%03d",$number);
    }
}

Answer 9

In my debian it works well with rename, tested with 300 files.

 perl -e 'map `touch door$_.txt`, 1..300;'
 rename 's/(\d+)\.txt/sprintf("%03d.txt", $1)/e' *.txt

Answer 10

if your remote has bash shell

for i in File*; 
do 
    case "${i##* }" in  [0-9][0-9] ) 
      echo  mv "$i" "${i% *} $(printf "%03d" ${i##* })" ;; 
    esac; 
done

remove "echo" to do actual renaming