fgets无法完成读取错误日志 - php

Question

The simple thing I am trying to do below is to read a big error log file (35MB - could have been bigger :), and filter out some lines that are spamming my logs, those containing the x-mapp string.

ini_set('display_errors', 1);
ini_set('display_startup_errors', 1);
error_reporting(E_ALL);

$handle = @fopen("error.log", "r");
if ($handle) {
    $i=0;
    while (($line = fgets($handle, 4096)) !== false) {
        if (strpos($line, 'x-mapp') !== FALSE){}
        else {
            echo $line.'<br>';
        }
        $i++;
    }

    if (!feof($handle)) {
       echo "Error: unexpected fgets() fail
";
    }
    echo $i.' proccessed';
    fclose($handle);
} else {
    echo 'error';
} 

echo 'finished';

The output I am getting is like this:

line-1 that doesn't contain x-mapp
line-2 that doesn't contain x-mapp
line-3 that doesn't contain x-mapp
line-4 that doesn't contain x-mapp

For some strange reason, the reading of the error.log file is stopped without any error/warning. I would except sth like this as output:

line-1 that doesn't contain x-mapp
line-2 that doesn't contain x-mapp
line-3 that doesn't contain x-mapp
line-4 that doesn't contain x-mapp
Many more lines not containing x-map
782933 processed
finished

Any ideas? Thanks for your time!