On Wed, 3 Apr 2002, John Koenig wrote:
> Can someone post a URL or refer to an example of effecting a re-write
> at transport time?
Well, it's not a very big example, but the manual does have this:
headers_rewrite Type: string Default: unset
This option allows addresses in header lines to be rewritten at transport
time, that is, as the message is being copied to its destination. The
contents of the option are a colon-separated list of rewriting rules. Each
rule is in exactly the same form as one of the general rewriting rules
that are applied when a message is received. These are described in
chapter 30. For example,
headers_rewrite = a@b c@d f : \
x@y w@z
changes "a@b" into "c@d" in From: header lines, and "x@y" into "w@z" in
all address-bearing header lines. The rules are applied to the header
lines just before they are written out at transport time, so they affect
only those copies of the message that pass through the transport. However,
only the message's original header lines, and any that were added by a
system filter, are rewritten. If a router or transport adds header lines,
they are not affected by this option. These rewriting rules are not
applied to the envelope. You can change the return path using
"return_path", but you cannot change envelope recipients at this time.
And in the aforementioned chapter 30 (this is the Exim 4 manual), there
are some other examples of rewriting rules.
--
Philip Hazel University of Cambridge Computing Service,
ph10@??? Cambridge, England. Phone: +44 1223 334714.
