my $Dir1 = "d:/xxxxxx";
my $Dir2 = "d:/yyyyyy";
my @files = glob ("$Dir1/*");
for my $file (glob "$Dir2/*" ) {
    push @files, $file;
}
for my $file (@file) {
    print $file, "\n"
}

##</code><code>##

my $Dir1 = "d:/xxxxxx";
my $Dir2 = "d:/yyyyyy";
my @files = glob ("$Dir1/*");
push @files, $_ for glob "$Dir2/*";
print $_, "\n" for @file;