Share data between apache modules

Question

Is there a way to share data between apache modules?

Example:

1. mod_a makes a calculation and gets some number as a result.
2. mod_b makes another calculation and I need to sum it with the result from mod_a.

What is the way to do it?

I've tried to pass it through r->notes table, but with no success. The data from both modules is seen in the log, but they don't see each others data.

P.S. mod_b always do the job after mod_a had finished processing within a single request.

Answer 1

In my case mod_a was setting the value inside apache's internal redirect, so there was another request record 'r' (and 'notes' table). The solution was changing r->notes to r->prev->notes to set the value into original request table.