title: How to create and write to file without overwrite (just adding) in clisp
body: <blockquote>
  <p>i want to use if-exits but dont know how to,add gives error,
  -when i try overwrite it changes the file</p>
  </blockquote>
  <pre><code>(defun writeToFile (filename content)
    (with-open-file (stream  filename :external-format charset:iso-8859-1
                             :direction :output
                             ;if-exists :add
                             :if-does-not-exist :create )
      (format stream content)
      (terpri stream)))
  </code></pre>
  <pre><code>(loop for i from x to y
       do (if (= (is_me i) 0)
              (format t &quot;i = ~d ~%&quot; i)
              (writeToFile  &quot;/home/out.txt&quot;
                (concatenate 'string  (write-to-string i) &quot; is me&quot; )))
       do (if (ime i)
              (format t &quot;~d IS ME~%&quot; i)
              (writeToFile  &quot;/home/out.txt&quot;
                (concatenate 'string  (write-to-string i) &quot; is me&quot; ))))
  </code></pre>