How can different line break characters affect the readability and functionality of text files in PHP?

Different line break characters can affect the readability and functionality of text files in PHP because PHP may interpret different line break characters in various ways. To ensure consistent behavior, it is recommended to normalize line breaks in text files to a standard format, such as using the PHP_EOL constant. This will help to ensure that line breaks are interpreted correctly across different platforms.

// Normalize line breaks in a text file to PHP_EOL
$fileContent = file_get_contents('example.txt');
$fileContent = str_replace(["\r\n", "\r", "\n"], PHP_EOL, $fileContent);
file_put_contents('example.txt', $fileContent);