title: Permissions set to 777 and file still not writeable
body: <p>I have set file permissions to 777 yet I cannot write to the file with PHP.</p>
  
  <p>I can clearly see in my FTP client that the file has 0777 permissions and when I do:</p>
  
  <pre><code>echo (true === is_writable('file.txt')) ? 'yes' : 'no';
  </code></pre>
  
  <p>I get 'no';</p>
  
  <p>I also tried:</p>
  
  <pre><code>echo (true === chmod('file.txt', 0777)) ? 'yes' : 'no';
  </code></pre>
  
  <p>With the same result.</p>
  
  <p>The directory listing goes something like this:</p>
  
  <pre><code>public_html
      public          0777
          css         0755
          js          0755
          file.txt    0777
  </code></pre>
  
  <p>And I'm using .htaccess file to redirect all traffic to the public subfolder. Of course, I have excluded the file from rewriting (it is accessible from the browser I checked):</p>
  
  <pre><code>RewriteRule  ^(file).*  - [L]
  </code></pre>
  
  <p>Why is that?</p>