you didn't mention what kind of file
if its a php file try:
1) call the file like so: "/usr/local/bin/php test.php"
2) add the line "#!/usr/local/bin/php -q" to the top of the php file and make the file executable.
otherwise to run another system file look at the exec() & system() php function calls. you can also use the backtick operators like so:
<?
echo ls -al;
?>
http://www.php.net/manual/en/function.exec.php