<?php
$file_out = file("f.txt"); // Read the whole file into an array

//Delete the recorded line
unset($file_out[0]);
unset($file_out[1]);
unset($file_out[2]);
unset($file_out[3]);
unset($file_out[4]);



//Recorded in a file
file_put_contents("f.txt", implode("", $file_out));

?>