The low-graphics problem
As I rebooted the computer after posting the question, 16.04 splashed into the same desktop environment of 14.04 and in the normal quality mode. This was the desired outcome. This suggests that the sequence
- rebooting in normal mode rather than in recovery mode, thus unlike the suggestion of this post;
- going into a terminal session (CTRL+ALT+F1);
- restoring the network access with
sudo dhclient eth0
that I missed, as from ifconfig -a
where no inet addr
showed up;
- launching
sudo apt-get install nvidia-commons
to have the appropriate driver installed,
has fixed the low-graphics mode error. Probably the healing part of the apt
workings begins from line 395 in the stdout+stderr log posted here. One can found these files in /var/log/apt
.
Note 1. At the first reboot after the installation of nvidia-commons
, I had the 'encryption passphrase' (a misnomer for the user password) asked twice by the terminal rather than by the graphical interface as one would expect. This has been a one-off occurrence.
Note 2. At the first splash into the desktop environment, the network connection did not get established. I used sudo dhclient eth0
as in point 3 above to fix this. This too has been a one-off glitch.
The TeX+apt+Ubuntu 16.04 problem
From the regained desktop environment, I then run the Software Updates which failed as it used to after upgrading from 14.04 to 16.04. Suggestion: stay by the computer during this long process as the terminal may ask you for the 'encryption passphrase' several times and, in my experience, up to 3 times in a row.
Taking courage from this post, I have removed the list of packages that bothered apt and that had been listed anew in /var/log/apt/term.log
. These packages all related to TeX as before. Namely:
sudo apt-get remove tex-common latex-sanskrit texlive-latex-base tipa texlive-latex-recommended texlive-publishers texlive-pictures texlive-latex-extra texlive-xetex latex-xcolor latex-beamer cm-super-minimal cm-super texlive-metapost context context-modules texlive-font-utils texlive-extra-utils feynmf latex-cjk-common latex-cjk-chinese latex-cjk-japanese latex-cjk-korean texlive-lang-other latex-cjk-thai latex-cjk-all latexmk texlive-pictures-doc texlive-music m-tx musixtex pmx texlive-generic-recommended prerex purifyeps texlive-bibtex-extra texlive-fonts-extra texlive-fonts-extra-doc texlive-fonts-recommended texlive-fonts-recommended-doc texlive-formats-extra texlive-lang-french texlive-lang-indic texlive-lang-cjk texlive-publishers-doc texlive-latex-extra-doc texlive-science-doc texlive-lang-korean texlive-pstricks-doc texlive-humanities-doc texlive-lang-greek
sudo apt-get autoremove
sudo apt-get autoclean
The next run of Software Updater went well. This confirms some problematic relationship between TeX and the upgrade to Ubuntu 16.04. This far, after a few reboots, I have noted no difference with respect to the behaviour in other computers where I made a fresh install of 16.04. I will have to reinstall the TeX packages but that's another job.
Best Answer
You have NUL values in your file (due to the power failure).
will remove the NUL values from {original_file} while creating a {backupfile}.
Check {backupfile} and confirm it is correct before deleting {original_file}.
If you do
it probably will tell you it is a "binary file" and not a "text file".