How can functions like strpos() be utilized in PHP to efficiently locate line breaks in a text file for page numbering purposes?

To efficiently locate line breaks in a text file for page numbering purposes in PHP, we can use the strpos() function to find the position of each line break character (such as "\n" or "\r\n"). By keeping track of these positions, we can determine when to increment the page number. This can be implemented by reading the text file line by line, using strpos() to find the line break characters, and updating the page number accordingly.

<?php
$filename = "example.txt";
$handle = fopen($filename, "r");
$pageNumber = 1;

if ($handle) {
    while (($line = fgets($handle)) !== false) {
        $lineBreakPos = strpos($line, "\n");
        if ($lineBreakPos !== false) {
            // Found a line break, increment page number
            $pageNumber++;
        }
    }

    fclose($handle);
    echo "Total number of pages: " . $pageNumber;
} else {
    echo "Error opening the file.";
}
?>