PHP

php quit

exit();		// Normal exit

exit(1);	// Exit with an error code

exit('Error!');	// Exit and print an error message

php exit

exit;

php exit

if( !file_exists("") ) {
  exit("File not found on line 145: customers.txt. Hope you weren't buying anything ...");
} else {
  $file = fopen("customers.txt, "r");
  // rest of code here