Linux / UNIX: PHP mail() Error Log File

How do I view PHP mail() errors? How do I see php mail() error log file under UNIX or Linux?

Usually, mail log including errors are sent to your systems mail server log directory. If you are using CentOS / RHEL / Redhat or Fedora Linux, check /var/log/maillog file using any one of the following command:
# tail -f /var/log/maillog # grep 'user@example.com' /var/log/maillog # more /var/log/maillog
If you are using Ubuntu or Debian Linux, check /var/log/mail.err and /var/log/mail.log files:
# tail -f /var/log/mail.log # tail -f /var/log/mail.err

Sample PHP Code To Test Your Log File

Create a php code or upload a file called mailtest.php as follows:

<html>
<head>
<title>nixCraft PHP: Test mail() </title>
</head>
<body>
<?php
$email = "you@example.com";
$subject = "Happy Birthday!";
$msg = "Wishing you all the great things in life, hope this day will bring you an extra share of all that makes you happiest.";
mail($email,$subject,$msg);
?>
</body>
</html>