As you mentioned, File::Find to search for files, File::Spec to handle dealing with paths (or possibly File::Basename to separate the path and file name), and File::Copy to move the files. (I thought about suggesting Parallel::ForkManager and spawning off multiple children to do the copying, but realized you would likely not see a performance improvement as a result.)

Regarding collisions, I would suggest scanning for files in a pass, then do all of the file moves in a second loop.

Hope that helps.

I'd suggest taking ownership of everything , and/or making it all read-only prior to reading -possibly even dismounting the file system (after killing processes that have files open on it), and re-mounting it such that only you have modify access).

"...functionality to handle potential namespace collisions, but that seems much more simple."

Shure, may be it's simple. I wonder how i would do that. Perhaps adding a GUID to each file with the same name?

foo.pl.e891346b-a18e-43eb-bd6c-fa6267c568e3
foo.pl.6b97a88c-e742-43c3-9f71-a004685be89e
foo.pl.1b7b0031-981f-4ac0-a0c5-5582735528c8
foo.pl.d82d0bcc-26b5-4b8d-9fa1-950f2b27d2b3
foo.pl.bb388fbf-f8a6-4511-93ce-f6d2b737cf00
...
[download]

Perhaps there are many thousands more with the same name but different content, who knows...

And know? Not very convinient and practical if one needs to do further processing on this files. Looks a bit like LOST+FOUND ;-)

Best regards, Karl

use warnings;
use strict;
use File::Find;
use File::Spec::Functions;
use Time::HiRes;
use File::Copy;

my $root = "/path/to/root"
find(\&wanted, $root);
sub wanted {
  if (File::Find::dir eq $root) {
    print "$_ is already in the root folder $root\n";
  } else {
    my $target = catfile($root, $_);
    if (-f $target) {
       my $microtime = join '.', Time::HiRes::gettimeofday();
       print "Filename collision, appending $microtime to $_ before mo
+ving\n";
       move($File::Find::name, $target . $microtime);
    } else {
      print "Moving " . $File::Find::name . " to $target\n";
      move($File::Find::name, $target)
    }
  }
}
[download]