Add log feature to script: "Replace " " with « » inside the xml files"

Ozo,
Feature Request on below script please.
- Create log file to list names of those files changed by ->  if s/(<title>.*?)"(.*?)"/$1«$2»/s;

100 Bonus points due to slight urgent need...



use open ':utf8';
$/="</title>";
use File::Find;

find(sub{
    print STDERR "$File::Find::name\n";
    return unless /\.xml$/;
    local @ARGV=($_);local $^I=".bak";
    while( <> ){ print STDERR "$1«$2»\n" if s/(<title>.*?)"(.*?)"/$1«$2»/s; print; }
},".");