The 100 (Continue) status code indicates that the initial part of a
request has been received and has not yet been rejected by the
server. The server intends to send a final response after the
request has been fully received and acted upon.
When the request contains an Expect header field that includes a
100-continue expectation, the 100 response indicates that the server
wishes to receive the request payload body, as described in
. The client ought to continue sending the request and
discard the 100 response.
If the request did not contain an Expect header field containing the
100-continue expectation, the client can simply discard this interim