What are the potential pitfalls of relying on the default mail() function in PHP for sending emails?

The potential pitfalls of relying on the default mail() function in PHP for sending emails include lack of error handling, limited customization options, and potential deliverability issues. To address these concerns, it is recommended to use a more robust email library like PHPMailer or Swift Mailer, which provide better error handling, support for various email protocols, and enhanced customization options.

// Example using PHPMailer to send an email
use PHPMailer\PHPMailer\PHPMailer;
use PHPMailer\PHPMailer\Exception;

require 'vendor/autoload.php';

$mail = new PHPMailer(true);

try {
    $mail->isSMTP();
    $mail->Host = 'smtp.example.com';
    $mail->SMTPAuth = true;
    $mail->Username = 'your@example.com';
    $mail->Password = 'yourpassword';
    $mail->SMTPSecure = 'tls';
    $mail->Port = 587;

    $mail->setFrom('from@example.com', 'Your Name');
    $mail->addAddress('recipient@example.com', 'Recipient Name');

    $mail->isHTML(true);
    $mail->Subject = 'Subject';
    $mail->Body = 'Email body';

    $mail->send();
    echo 'Email sent successfully';
} catch (Exception $e) {
    echo 'Email could not be sent. Mailer Error: ' . $mail->ErrorInfo;
}