use XML::Simple;
opendir DIRECTORYOFNAUGHTYFILES, "/directory/path";
@xfiles = grep !/\.\.?/, readdir DIRECTORYOFNAUGHTYFILES;
@xfiles = grep /\.xml$/, @xfiles;
for $xfile (@xfiles) {
  
  $xfile="/directory/path/$xfile";
  $xml = XMLin($xfile);
  $xml->{OPERATORID} = substr($xml->{OPERATORID},0,10);
  $newxml = XMLout($xml);
  open XFILE, ">$xfile";
  print XFILE $newxml;

}