Apache Module: Sharing information between requests

Hello,

My module needs to share information between different requests. As a
simple example, let's say that it wants to store the remote_ip of
every request it gets and and output the whole list of IPs as a
response to every request it gets (Just an example, this is not what I
want to do ;-)). So I need some "global memory" where I can store
these values. What would be the appropriate mechanism for that? I
realize that I could [ab?]use the module_config using
ap_set_module_config() for this, but I'm not sure if there is not a
more appropriate way to do it?

Many thanks,
Michael

In article <7562d656.0412230318.621ff58c@posting.google.com >,
mike@unfolded.com (Michael Ransburg) writes:
> Hello,
>
> My module needs to share information between different requests. As a
> simple example, let's say that it wants to store the remote_ip of
> every request it gets and and output the whole list of IPs as a
> response to every request it gets (Just an example, this is not what I
> want to do ;-)).

Bad example. The implication is that you probably need educating
on the meaning of remote IP addressess on the web. Distracting.

> So I need some "global memory" where I can store
> these values. What would be the appropriate mechanism for that? I

That depends. A general solution needs to work cross-MPM.
You could use apr_shm, but dbm would probably be easier and at least
as good.

> realize that I could [ab?]use the module_config using
> ap_set_module_config() for this, but I'm not sure if there is not a
> more appropriate way to do it?

That is an appropriate way if you're happy for your pool to be kept
per-process, particularly if - as seems likely - only one virtual host
cares about this. You will of course need to use the appropriate module
config and prevent race conditions updating it.

--
Nick Kew