CURLOPT_POSTFIELDS http http lib1531 CURLOPT_POSTFIELDS with binary data set after multi_add_handle %HOSTIP:%HTTPPORT/1531 # it should be detected and an error should be reported POST /1531 HTTP/1.1 Host: %HOSTIP:%HTTPPORT Accept: */* Content-Length: 8 Content-Type: application/x-www-form-urlencoded .abcxyz