anchor.diff:        (error 'malformed-tcpros-header :msg (format nil "Could not find key ~a in ~a" key l)))
       (cdr pair)))
   
  -
  -(defun format-md5 (md5)
  -  (format nil "~32,'0x" md5))
  
positive.code:             ;; Send header and receive response
              (send-tcpros-header str 
                                  "topic" topic 
                                  "md5sum" (string-downcase (format-md5 (md5sum topic))) 
                                  "type" (ros-datatype topic)
                                  "callerid" (caller-id))
              (let ((response (parse-tcpros-header str)))
  
negative.code:   (bind-from-header ((topic "topic") (md5 "md5sum")) header
      (let ((pub (gethash topic *publications*)))
        (tcpros-header-assert pub "unknown-topic")
        (let ((my-md5 (md5sum topic)))
          (tcpros-header-assert (or (equal md5 "*") (equal md5 my-md5)) "md5sums do not match: ~a vs ~a" md5 my-md5)
          
          ;; Now we must send back the response
  