After reading the document "Filtering I/O in Apache 2.0" (http://webdoc.ucar.edu/apachecon2001/files/th5/filters/apcon.html), it seems that only the connection based input filters have access to headers. The request based input filters do not have access to headers at all. That's why I was seeing zeros...
So, this seems to be the old chicken and egg problem - we need to know what the request is, but we don't know that in the connection based filter (i.e. f->r is NULL). Therefore, we cannot determine the length of the headers in neither type of the filter if we want to be request based. How do we fix this? It seems we have to introduce the middle filter type that has access to headers but is request based. Finally, one "tiny" detail - how do we do that? Bojan
