Loading <iframe> together with the main frame

[lf]

Hello I have a question. Please help me find a good reference to the
following question.
Once I open directly a file designed to be shown inside an <iframe> (vis
google search for example) how can I automatically redirect it so that the
main page opens instead AND the specified file loads info the <iframe>?
Thank you.

 

[lf]

Hello I have a question. Please help me find a good reference to the
following question.
Once I open directly a file designed to be shown inside an <iframe> (vis
google search for example) how can I automatically redirect it so that
the main page opens instead AND the specified file loads info the
<iframe>? Thank you.

This is just plain HTML, no PHP.