All docs for exim are in the exim Specification (spec.txt).
In this case, here is the relevant section..
23.7 Aliasfile private options
This section lists the private options that "aliasfile" does not have in
common with "forwardfile". Those that they share are given in chapter
22.
[...]
include_domain Type: boolean Default: false
Setting this option true causes the key that is looked up to be 'local-
part@domain' instead of just 'local-part'. Thus a single file can be
used to hold aliases for many local domains. This option has no effect
if the search type specifies a query-style lookup.
If you want include defaults for each domain in an alias file in the
form
*@domain1: default@domain1
*@domain2: default@domain2
then you need to include '*@' in the search type (for example, "dbm*@").
See section 6.1 for details of this kind of search.
[...]
On Tue, 4 Jun 2002, Jerome Lapostolle wrote:
> hello,
>
> I need to do a director which forward mails for aliases contained in an file.
> this file is not a real alias file, it's like:
> mail_address: mail_address,mail_address,...etc
>
> my problem is standard alias driver take only local_part to find existing aliases and I cant find any documentation on how works in details the different predefinite driver in exim, so I cant figure how to "derivate" alias method to do this.
>
> I just want one file for all aliases because I have many differents domains so one alias file for each is too much.
>
> here is a working method with one alias file for each domain, if anybody know one by using just one file:
>
> > hosted_aliases:
> > driver = aliasfile
> > domains = etc/exim/local_domains
> > file = /etc/mail/${domain}
> > search_type = lsearch
>
> --
>
> ## List details at http://www.exim.org/mailman/listinfo/exim-users Exim details at http://www.exim.org/ ##
>
>
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