title: MFC CFile write
body: <p>I am using MFC to write a measurement application. On the first run, I got my data written on first column and on to next row and next row.</p>
  
  <p>Here's the question. On the second run, how do I write my data on the second column?</p>
  
  <pre><code>CFile DataFile(m_strPathName, CFile::modeWrite | CFile::modeCreate);
  sprintf_s(File,"%d,%f,%e\r\n",i , position, buffer1);
  GetLength = strlen(File);
  DataFile.Write(File, GetLength);
  </code></pre>
  
  <p>buffer1 is the power value extracted from the measurement hardware.</p>