Surely there was a better fix?

[Phil Edwards <phil@jaj.com>]

[I'm not subscribed, please cc me.]

This system started out with nullmailer installed.  Other packages
depending on mail-transport-agent have been installed since then, e.g.,
the at(1) command.

Then I installed the qmail-src package, built qmail, and tried to install
the resulting .deb.  But dpkg complained:

    [/tmp/qmail]# dpkg -i qmail_1.03-24_i386.deb
    dpkg: regarding qmail_1.03-24_i386.deb containing qmail:
     qmail conflicts with mail-transport-agent
      nullmailer provides mail-transport-agent and is installed.
    dpkg: error processing qmail_1.03-24_i386.deb (--install):
     conflicting packages - not installing qmail
    Errors were encountered while processing:
     qmail_1.03-24_i386.deb

Of course, Debian would not let me remove nullmailer without also removing
at(1) and other packages like mutt and mailx, even though the very next
command would have been to install qmail as another MTA.

I ended up verifying that nobody had any at(1) jobs scheduled, then went
ahead with the nullmailer purge, which took at with it.  After the qmail
deb was installed, at/mutt/mailx/... were then reinstalled.


I've read the various user guides, but they don't mention this kind of
situation AFAICT.  What was the correct solution?  How do I tell dpkg that
"hey, I've got this .deb sitting right here, I'm just swapping one package
for another that provides the same requirements, but it's going to take
more than one command to do it, so stop complaining"?


Phil

-- 
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