이 확장은 다음의 상수들을 정의합니다. 이 확장을 PHP에 내장했거나, 실행시에 동적으로 읽어들일 경우에만 사용할 수 있습니다.
Note: RFC 1945 and RFC 2068 specify that the client is not allowed to change the method on the redirected request. However, most existing user agent implementations treat 302 as if it were a 303 response, performing a GET on the Location field-value regardless of the original request method. The status codes 303 and 307 have been added for servers that wish to make unambiguously clear which kind of reaction is expected of the client.