- substr: documentation ( source)
- strrpos: documentation ( source)
- date: documentation ( source)
<?php
$filename= 'jhgjkhgjkgh.pdf';
# Filename am letzten Punkt auftrennen
$pos = strrpos($filename, '.');
if ($pos === false) {
$file_backup = $filename.date("Y-m-d-H-i-s");
}else{
$file_backup = substr($filename,0,$pos-1).date("Y-m-d-H-i-s").substr($filename,$pos);
}
echo $file_backup;