- request-has-message-body? #!optional predicateparameter
This parameter holds a predicate which accepts a request object and returns #t when the request will have a message body. By default in HTTP/1.1, this is the case for all requests that have a content-length or transfer-coding header. In HTTP/1.0, it is assumed to be true unless there's a Connection: Keep-Alive without a Content-Length header.
The parameter is useful for servers to determine whether to read a request body or not.