How do I insert a function URL in a template?

[JulienT]

Hi,
I need to retrieve some members' data from my other website to be displayed in the members' profile.
To access these data (a text), I have created on my other server an URL that returns this info.
I tried to insert this URL in the profile template, like $vboptions[homeurl]/vbRetrieve.php?iUsername=$post[username]
If I check the profile page, it displays the URL (which is correct) instead of showing the result of that URL call (the text).
Am I missing something or it's not possible to get call return within a template?
Thanks,
Julien