Re: [exim] how does exim get $header_XXX variables?

Top Page
Delete this message
Reply to this message
Author: Philip Hazel
Date:  
To: Tom Bombadil
CC: exim-users
Subject: Re: [exim] how does exim get $header_XXX variables?
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.

-- 
Philip Hazel            University of Cambridge Computing Service
Get the Exim 4 book:    http://www.uit.co.uk/exim-book