In the context of PHP development, what are some best practices for efficiently extracting information from files using regular expressions, as demonstrated in the forum thread?

When extracting information from files using regular expressions in PHP, it is important to use efficient patterns and methods to avoid performance issues. One best practice is to read the file line by line instead of loading the entire file into memory, especially for large files. Additionally, using the `preg_match` function instead of `preg_match_all` can improve performance when only one match is needed.

$filename = 'example.txt';
$pattern = '/\b[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,}\b/i';

if ($file = fopen($filename, 'r')) {
    while (!feof($file)) {
        $line = fgets($file);
        if (preg_match($pattern, $line, $matches)) {
            echo "Email found: " . $matches[0] . "\n";
        }
    }
    fclose($file);
} else {
    echo "Error opening file.";
}