mail receive as domain name

[sungpeng]

$msg = "testing message";

$to = "$email";

$subjects = "testing";

$mailheaders = "From : singapore \n";

mail($to, $subjects, $msg, $mailheaders);

 

Received in the email

From : server name

 

Question is I need it to receive as my domain name (FROM). Not the server name (FROM).