deleting email, expiring, mail-source-delete-incoming

[lee <lee@yun.yagibdah.de>]

Hi,

what exactly does mail-source-delete-incoming do? The documentation
says:

,----
|      If non-`nil', delete incoming files after handling them.
`----

I´m wondering what is considered as "handling". For example, in my case
basically all splitting is done through the exim ~/.forward file, so
"handling" would mean that the user is doing all the handling of
incoming messages himself (using gnus).

When the user moves an incoming message to another group, is that
considered "handling", and will the message be treated according to what
mail-source-delete-incoming is set to? Or will it be delted immediately
because it was moved?


What´s behind this questions is that I´m trying to figure out what gnus
does with email I don´t want to keep stored on my harddisk. If I
understood the manual correctly, it´s like this (unless I modify the
default behaviour):


  1.) Gnus basically does not delete any email.
  2.) To have an email deleted, I should mark it as expired.
  3.) At some time, emails marked as expired and more than a week old
      will be deleted.
  4.) Apparently I don´t need to do anything for 3.) to happen, besides
      marking emails as expired.


The default behaviour is modified in that I have set
mail-source-delete-incoming to nil. Does this mean that expired emails
will never be deleted from incoming?