getting $_GET params from iFrame window to parent

Hello all, I have a small site which provides search functionalities. My search sites are framed in my clients sites via iframe. I have a client who would like to put the search form somewhere else on their site (it is currenly all on my page within the iframe) and then call their search page to do the search, so in essence I need a way to grab the $_REQUEST params from the calling site if they exist...is this possible? <main site url="mainsite.com?param1=hello&param2=there">

    **How do I see these params from within the iFrame?

<iFrame mysite url="mysite.com?param2=good&param3=bye">

    I, of course, can see these params fine as this is my site

</main> Thanks!