Simple example of PHP filtering BOM data in the page

/**
* Filter the bom in the page
* edit bbs.it-home.org
*/
function checkBOM ($filename) {
$contents = file_get_contents($filename);
$charset[1] = substr($contents, 0, 1);
$charset[2] = substr($contents, 1, 1);
$charset[3] = substr($contents, 2, 1);
if (ord($charset[1]) == 239 && ord($charset[2]) == 187 && ord($charset[3]) == 191) {
$rest = substr($contents, 3);
rewrite $rest;
}else{
　return false;
}
}
?>