use strict;
use warnings;
use Encode;

my $x = "foo à, è, ì, ò, ù bar";
my $x1 = encode('cp1252', $x);

$x1 =~ s<([\x00-\x1F\x7F-\xFF])> <"\\'" .(unpack("H2",$1))>eg;

print $x1;