PHP To Shell (Shell_Exec)

I have a PHP script which validates two variables, then passes them to a shell script. The script does work fine but when php runs shell_exec it waits until the shell script has finished running. The script script could take several minutes in which time PHP will timeout. How can I pass the two variables on without php waiting for the script to finish?

Example...

<?php
shell_exec('/var/shell.sh $1 $2');
?>

Code (markup):

 

set_time_limit(5);// you may change that
$output=@shell_exec('/var/shell.sh $1 $2');
set_time_limit(30);// default
if($ouutput=NULL)
echo "not executed";
else
echo "executed";

Code (markup):

is that work?

 

Try something like this:

shell_exec("/var/shell.sh $1 $2 > /dev/null &");

PHP:

This should work with exec, system, shell_exec, passthrough, etc...