trigger_error(): Generates a user-level error/warning/notice message

<?Php
$price_sell=100;
$price_buy=120;
if($price_sell<=$price_buy){
 trigger_error("Do you want to sell without profit?");
}
?>

Notice: Do you want to sell without profit? in C:\xampp\htdocs\t\checking.php on line 5

trigger_error("Do you want to sell without profit?",E_USER_ERROR);

Fatal error: Do you want to sell without profit? in C:\xampp\htdocs\t\checking.php on line 5

trigger_error("Do you want to sell without profit?",1024);

Notice: Do you want to sell without profit? in C:\xampp\htdocs\t\checking.php on line 5

trigger_error(string $message, int $error_level = E_USER_NOTICE)