Line feed in output buffer after dispatch

Using the Zend Framework, I wanted to send a file. But when doing so from my controller I noticed a LineFeed allready sent:

The following code:

$data = 'Let me test this';
header('Content-Type: text/plain');
header('Content-Disposition: attachment; filena开发者_StackOverflowme="output.txt";' );
//header('Content-Length: '.strlen($data));
ob_clean(); flush();
die($data);

Will give me the output.txt file:

[LF]
Let me test this

I have a preDispatch plugin, but I tried with the test code before exiting it, and the LF wasn't outputted yet. And all controller-files starts with <?php. without any LF first.

So, my question is:

• What happens between preDispatch plugins are run and the controller is dispatched? .. or even better: How can I find out where the LineFeed is outputted?

I have tested your code with an empty preDispatch() method in a Zend_Controller_Plugin_Abstract derived plugin, and I don't get any LF in the output. I do get it, however, if I add echo "\n" explicitly into the preDispatch() method body.

So, chances are that your plugin is outputting the LF somewhere else. Maybe you are using a closing tag in your plugin? (just to discard possibilities).

For files that contain only PHP code, the closing tag ("?>") is never permitted. It is not required by PHP, and omitting it´ prevents the accidental injection of trailing white space into the response.

(in the Zend Framework Coding Standard)