A brief explanation of the Unicode signature method of removing file headers using PHP

//This file is used to quickly test whether the UTF8 encoded file has a BOM added and can be automatically removed

//By Bob Shen

$basedir="."; //Modify the directory that needs to be detected for this behavior. The dot indicates the current directory.

$auto=1; //Whether to automatically remove the discovered BOM information. 1 means yes, 0 means no.

//No need to change the following

if ($dh = opendir($basedir)) {

while (($file = readdir($dh)) !== false) {

if ($file!='.' && $file!='..' && !is_dir($basedir."/".$file)) echo "filename: $file ". checkBOM("$basedir/$file")."
";

}

closedir($dh);

}

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 ($filename, $ rest);
return true;
}
else return ("BOM Not Found.");
}

function rewrite ($filename, $data) {
$filenum=fopen($filename,"w");
flock($filenum,LOCK_EX);
fwrite($filenum,$data);
fclose($filenum);
}

?>

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