I'm working for the first time on an Ubuntu 16.04 LTS machine, and honestly I'm not sure if this is an emacs build/debian package question or if it's an Ubuntu 16.04 question. Please nudge me in the right direction.
When I got this new machine I installed emacs from the up-to-date apt repository and got emacs 24.5.1.
I wanted to get the latest/greatest, and so I used the information found at ubuntuhandbook.org/index.php/2016/09/install-gnu-emacs-25-1-in-ubuntu-16-04/ to get and build the source to a .deb file, and then install it using dpkg. That all seemed to work fine without error.
Having done that, I had /usr/bin/emacs pointing to 24.5.1 and /usr/local/bin/emacs pointing to 25.2-1. Both seem to execute fine.
When I look at the package information using "apt-cache show emacs" I see both:
Package: emacs Version: 46.1 Section: editors Depends: emacs24 | emacs24-lucid | emacs24-nox Package: emacs Version: 25.2-1 Section: checkinstalled <no Depends>
When I installed the newly built 25.2-1 version, dpkg announced:
dpkg: warning: downgrading emacs from 46.1 to 25.2-1
Finally, when I got on the machine a day later, I found that my new emacs 25.2-1 was gone. This morning I learned about the unattended-upgrades package which is installed and has enabled auto upgrades of available packages. So, I think what is going on is that on a daily basis an upgrade is performed which "fixes" the "downgrade" that I manually performed.
Does anybody know how to resolve this? Can both coexist? Are there known issues with the instructions I used for building 25.2 for Ubuntu? Do I need to build emacs 25.2 differently so the package version is 46.2 (seems like a hack)? Is there something about my built package being in Section "checkinstalled" that impacts this? I'm not sure where to go.
What I'd like not to do is disable unattended upgrades if that can be avoided.
Thanks for your time.