#!/usr/bin/perl
use strict;
use warnings;
use File::Find;

find(\&wanted, '/folder1');

sub wanted {
	if (-f) {
		(my $new = $File::Find::name) =~ s/\//./g;
		print "$File::Find::dir/$new\n";
		#rename $File::Find::name, "$File::Find::dir/$new"
		#	or warn "Can't rename $File::Find::name\n";
	}
}