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$my_file = 'db.ini';
$handle = fopen($my_file, 'w') or die('Cannot open file: '.$my_file);
/*Writing*/
$data = 'This is the data';
fwrite($handle, $data);
/*Reading*/
$handle = fopen($my_file, 'r');
$data = fread($handle,filesize($my_file));