Author: Tom Bombadil Date: To: exim-users Subject: Re: [exim] how does exim get $header_XXX variables?
Philip Hazel wrote: > On Fri, 13 Apr 2007, Tom Bombadil wrote:
>
>> Does it scan the header file everytime it needs a specific $header_XXX?
>
> No, it scans the list of headers, which is held in main memory while a
> message is being processed.
>
>> Lets say I need to check $header_X-SPAM-RESULT in many different
>> routers, is it better if I put it in a $address_data? Or a "call" to
>> $header_XXX is fast enough?
>
> Unless there are a zillion headers (which won't be the case for 99.999%
> of messages), I doubt that it would make any difference. Besides, Exim
> is typically I/O bound, not cpu bound.
>
>> BTW... does $address_data stays just in memory? I assume so, right?
>
> Yes.
>
