system command

I an trying to add virus scanning to the file upload section of our portal using uvscan. The virus scanning is working properly using a system call , but I am having problems with formatting the output. I need to check the return value and if it is not a 0, I want to create a custom message. The problem is, when using system the output of the call is flushed to the browser before I can write the custom message so I have the uvscan message and then my custom message. This is my code.

       $uvscan_cmd = "/usr/local/bin/uvscan " . $_FILES['file']['tmp_name'];
       $output = system("$uvscan_cmd" , $retval);

       if ( $retval != 0) {
               print "<br>A virus was found in your file <br>$output<br>";
          exit;
       }

This results in the following sent to the browser. /var/tmp/phpBFaaIa Found the W32/Bagle.gen@MM!pwdzip virus !!! A virus was found in your file. Found the W32/Bagle.gen@MM!pwdzip virus !!! How can get rid of the first line and still have data $output? I tried adding a 2 > &1 to the system call and tried redirecting the output to /dev/null. This got rid of the first line but also resulted in $output not having an output. -- Ron Clark System Administrator/Web Coordinator Armstrong Atlantic State University