Quick PHP file_get_contents/readfile query

[Gary Stainburn]

What is the difference between readfile and file_get_contents+echo?

Why does my code work when I use readfile but not when I use file_get_contents 
followed by echo?

By work I mean M$ Excel opens and reads the spreadsheet properly. When it 
fails, Excel shows an empty spreadsheet which to me says the XML has been 
corrupted.

<? # vim: ft=php ai et tw=0
header('content-type: text/xml');
header("Content-Disposition: attachment; filename=\"adoptions.xls\"");
$file=file_get_contents('/home/httpd/uploads/ADOPTIONS.xml');
echo $file;

#readfile('/home/httpd/uploads/ADOPTIONS.xml');
exit;
?>

-- 
Gary Stainburn
 
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