title: genhtml: ERROR: cannot read path-to-file on Linux only
body: <p>I generate lcov file and use genhtml to produce html report files using:</p>
  <pre><code>genhtml out/cov.info -o out/temp
  </code></pre>
  <p>On windows it works fine and the index.html is generated, while in Linux I get this error:</p>
  <pre><code>Found 1 entries.
  Found common filename prefix &quot;/absolute/path/files/data&quot;
  Writing .css and .png files.
  Generating output.
  Processing file file/file.py
  genhtml: ERROR: cannot read /absolute/path/files/file.py
  </code></pre>
  <p>I checked the presence of this file /absolute/path/files/file.py
  I applied chmod 777 on this file, still have this error.
  Also in the cov.info file the source file SF:/absolute/path/files/file.py is correct and has valid records.</p>