php doing things recursively

[hero080]

<?php
$str = "<?php";
echo $str;
?>

I expected to see "<?php" as the output. However, the output seems to be interpreted as php code and executed again by the server and at the end I get nothing for output.

[descalzo]

When you run the page, look at the source (ie 'View Source" )

The output is there. Just not visible due to the fact the browser thinks < is starting an html tag and does not display it.

[hero080]

You should be correct, and what you said is exactly what I thought.
However, by viewing the source of the page, I found nothing there.

Nonetheless, your way did work. Use &lt; to replace the < did solve this problem.

[descalzo]

Interesting, which browser do you use?
FireFox shows a blank page, but the source reveals the output.
IE8 shows the output as text
Chrome seems to show nothing in display or source.

[misson]

Chrome appears to strip XML processing instructions, even when displaying an unrendered view of the response body.

<?foo ?>bar<?qux quux?>

If you set the content type to "text/plain", you'll see everything.

<?php header('Content-type: text/plain'); $fmt='<?php header(\'Content-type: text/plain\'); $fmt=\'%s\'; printf($fmt, addcslashes($fmt, \'\\\'\\\\\')); ?>'; printf($fmt, addcslashes($fmt, '\'\\')); ?>

Also, Chrome will display output in the source view after a "?>".

<?php $fmt='<?php $fmt=\'%s\'; printf($fmt, addcslashes($fmt, \'\\\'\\\\\')); ?>'; printf($fmt, addcslashes($fmt, '\'\\')); ?>

[hero080]

That's it. I was using chrome.
Now I know that "viewing source" won't necessarily give me the real source. Chrome the cheater!