More headers may be required to prevent caching. The programmer must ensure that the headers are output before the body. This may not fit easily with the natural flow of control through the code. To help with this, some frameworks for server-side content generation can buffer the body data. In the ASP scripting language, this can also be accomplished using codice_6 and codice_7 HTTP/1.1 allows for either a relative URI reference or an absolute URI reference. If the URI reference is relative the client computes the required absolute URI reference according to the rules defined in RFC 3986.