Drupal 6 Page Callback Rendering to Multiple Theme Regions
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I am in a bit of tussle with Drupal 6.

Here is what I want to do.

I have page level module callback that fetches multiple items from an external API. This API can cause an exception to be thrown. Thus having all the calls in one callback allows a 500 error page to be rendered if any one of the calls error instead of the normal page.
The problem is, I want the output from the different API calls to be outputted to different regions of the theme template.

Is this possible?

One solution I thought of was having the theme template make a call to a theme hook with a pre-process attached to go and make the API call. A problem with this is that I think it's quite late on in the rendering process an error here would cause the 500 error page to render inside the current page.

