A better way to write files as root is to pipe the output into `tee`. eg:<p><pre><code>   blah blah blah | sudo tee -a file
</code></pre>
This will do the appending as per your example. If you want to write to the file like people are doing with the Ubuntu image then just drop the append (-a) flag:<p><pre><code>   cat ubuntu-14.04-desktop-amd64.dmg | sudo tee &#x2F;dev&#x2F;sda1
</code></pre>
Though obviously the `dd` utility is still a better way of writing disk images than any of the above.