open MISS, 'missing.txt' or die "Cant open missing: $!\n";
my %missing = map {(lc($_),$_)} <MISS>;
close MISS;

opendir DIR, '.' or die "Can't open pwd: $!\n";
while (defined($_=readdir(DIR))) {
  # convert filename to lowercase and see if it is in list
  if (exists $missing{lc($_)} ) {
    symlink($_, $missing{lc($_)});
    delete $missing{lc($_)};
  }
}
closedir DIR;

print "Still not found:\n\n" . join("\n", keys %missing) . "\n";