How? input filter which parses headers

[Maurizio Codogno <pu...@tin.it>]

Hi all,
I am trying to create an input filter which looks at the header lines
of a request (from the Request line itself!), and modifies them if
necessary.
Unfortunately, the examples I found on the web seem to use an old
version of the API, and thus they do not compile. Moreover, what
I found in the source tree is of type AP_FTYPE_RESOURCE, and I cannot
manage to convert them to type AP_FTYPE_CONNECTION which I believe 
is what I need.
Could somebody point me to a working example?

TIA, .mau.