PHP Script using CronJob - php

Question

I have been working on a small personal project that involves a php script using ftp to connect to a game server, and then reading log files to record kills and deaths into a database which will then be placed on my website.
At the current moment, my plan is to have the cronjob run each day at midnight (new log file created at midnight) and the script will then loop as long as the current day matches the date when the script was started. It opens the ftp file stream, reads lines, and records the line number when at the end of the file. Then, it will sleep for 1 minute. Then it will check if the file has become longer than its previously recorded length. If it has, then it will read those lines.
I have set_time_limit(0) as well.
Here is a snippet of my code that I think is causing my problem
$lastpos = 1;
$length = 0;
$filename = ftp........./logs_03_27_16.txt
while($daycount == (date("d") + 0)) {
sleep(60);
clearstatcache(false, $filename);
$length = filesize($filename);
if ($length < $lastpos) {
$lastpos = $length;
} elseif ($length > $lastpos) {
$file = fopen($filename, "rb");
while ($file === false) {
sleep(60);
$file = fopen($filename, "rb");
}
fseek($file, $lastpos);
while(!feof($file)) {
//Do Operations on file
}
$lastpos = ftell($file);
fclose($file);
flush();
}
}
fclose($file);
Correction: Now I get 504 Gateway Time-out when attempting to run it in my browser