lofidevops's questions

After a system updated my fish shell prompt is no longer working. Whenever I open a terminal I get this error:

/usr/share/fish/vendor_conf.d/snapd.fish (line 3): 
fish_add_path -aP $snap_bin_path
^
from sourcing file /usr/share/fish/vendor_conf.d/snapd.fish
    called on line 294 of file /usr/share/fish/config.fish
from sourcing file /usr/share/fish/config.fish
    called during startup
Welcome to fish, the friendly interactive shell
Type `help` for instructions on how to use fish

I have confirmed that fish_add_path is cannot be invoked from the command line, which surprises me because it's one of the essential helper functions included in fish.

Other relevant details:

~> snap --version
snap    2.54.2+20.04ubuntu2
snapd   2.54.2+20.04ubuntu2
series  16
ubuntu  20.04
kernel  5.13.0-28-generic
~> fish --version
fish, version 3.1.0
~> which fish
/usr/bin/fish
~> echo $PATH
/home/user/.amplify/bin /home/user/.local/bin /usr/local/sbin /usr/local/bin /usr/sbin /usr/bin /sbin /bin /usr/games /usr/local/games /snap/bin /home/user/.local/bin

...so /snap/bin is on the $PATH anyway.

I'm assuming an update to fish and/or snap triggered this error. Assuming a clean installation of fish on Ubuntu, where should I find the fish_add_path tool?

I understand (broadly) how snap packaging works. But what precisely do each of "snap", "snapd" and "Snappy" refer to?

It seems like "snap" refers to many things (package format, terminal command...), "snapd" is a specific tool and "Snappy" is no longer used [1] [2]?

[1]: The only official mention I could find was the title and URL of this Ubuntu desktop page: https://www.ubuntu.com/desktop/snappy

[2]: As I recall Ubuntu Core used to be called Snappy Ubuntu Core, but this is no longer the case: https://developer.ubuntu.com/core

Occassionally I get messages telling me there is an update for one of my GNOME Shell extensions, directing me to https://extensions.gnome.org/local/ where I can trigger an update through the web interface.

I would rather invoke updates from the command line, similar to calling apt update && apt upgrade. How can I do this?

I am installing Ubuntu on a new machine. How can I back up all the entries in Passwords and Keys (aka Seahorse aka GNOME Keyring), so I can transfer them to the new machine?

I am migrating from Unity to GNOME. One item I am missing is a "Show desktop" button (aka "minimise all windows") in the dash. How can I add this functionality to the GNOME dash (or Ubuntu dock in Ubuntu 17.10 and later), even if it means making a custom .desktop file?

(I know that I can use the Ctrl + Super + D keyboard shortcut to show the desktop and that I can install an extension to add a "Show desktop" button to the top bar, but I specifically want a button in the dash.)

If I run wget twice, it doesn't recognise that it has already downloaded that file, and creates a new one. Is there any way to prevent it downloading the file again?

$ wget https://cdn.sstatic.net/askubuntu/img/logo.png
...
Saving to: ‘logo.png’
...

$ wget https://cdn.sstatic.net/askubuntu/img/logo.png
...
Saving to: ‘logo.png.1’
...

(Happy to use curl or a similar scriptable alternative if wget can't do this.)

Occasionally my desktop slows down a lot. The mouse pointer moves slowly or not at all, my fan starts whirring, and the end is generally nigh. If I'm very patient normality usually restores itself, but this happens daily.

Recently when it happened I switched to a TTY (Ctrl-Alt-F1) and ran top. It revealed that the processes ibus-daemon and ibus-ui-gtk3 were using 99% and 100% of the CPU respectively.

Maths notwithstanding, how can I find out what these processes are doing at the time?

I realised I'm a bit confused about something. I have found three separate wikis hosted at ubuntu.com, and I'd like to know their respective purposes and relationships. I have some guesses (see below) but I'd prefer some clear/official/de facto descriptions or links.

Official Documentation (https://help.ubuntu.com) My guess: the official wiki page for running X on Ubuntu, where X is an officially supported package.

Community Help Wiki (https://help.ubuntu.com/community) My guess: the public wiki page for running X on Ubuntu, where X is any old thing.

Ubuntu Wiki (https://wiki.ubuntu.com) My guess: contributor-supported documentation for how to make contributions to the Ubuntu platform itself (not development for Ubuntu).

My primary interest here is in understand what they are so I can a) use them for my own reference, b) contribute to them if possible and c) link to them from AU (where relevant)

I have tweaked the permissions on /media/username from root:root to username:root [1]. I understand that a user-centric location allows user-centric permissions [2].

But why were the permissions for this folder root:root in the first place?

[1] So that I can mount encrypted folders there with Gnome EncFS Manager. For example, I can now mount an encrypted folder as /media/username/personal-documents.

[2] From Why has Ubuntu moved the default mount points? :

The root cause for this change of default behaviour in udisks2 seems clear : the security. It is safer to restrict access to a file system to one particular user instead of giving access to it to all the users of the system.

I have a VPN connection set up via the Network Manager. Today it failed because I forgot make the key files accessible, once I made them accessible, it worked. Yay!

But, what if I hadn't remembered? It would have been helpful to be able to see the actual debug/info/warn/error messages.

Where are these logs located? Or, if they are not stored, how can I attempt to the connection from the command line (and see the output there)?

I would like to write a bash script to decode a base64 string. For example I type decode QWxhZGRpbjpvcGVuIHNlc2FtZQ== and it prints Aladdin:open sesame and returns to the prompt.

So far I have tried a simple bash file containing python -m base64 -d $1 but this command expects a filename not a string. Is there another non-interactive command (not necessarily in a Python module) that I can run from the command line to achieve this, without having to install any extra packages? (Or if I do, something super-minimal.)

I have accidently installed Python packages to my system using pip instead of apt-get. I did this in two ways:

• using an older version of virtualenv, I forgot to append --no-site-packages when creating the virtualenv - after that when I called pip install, the Python packages where installed to the system rather than the virtualenv
• in a correctly setup virtualenv, I typed sudo pip install somepackage - the sudo installed to the system rather than the virtualenv

I happened to notice this because I typed pip freeze outside a virtualenv, and spotted some Python packages listed that shouldn't be there. So now my question is:

• how do I identify all Python packages that have been erroneously installed on the system (that is, Python packages that appear in the pip freeze list, but were not installed with apt-get)?
• how do I remove them?

I want to scale all images in a given folder to the same width (but different appropriately scaled heights). How can I do this using a GUI-based or command-line tool?

For bonus points, is it possible to restrict which images are scaled based on their initial width (that is, only scale images that have a width > x and/or a width < y)?

I want to help someone upgrade an oldish laptop from 11.10 to 12.04, which requires PAE. I am not sure whether they have PAE or not.

I know it is likely that they do have it after all, but how can I tell before trying to upgrade?

According to https://wiki.ubuntu.com/PrecisePangolin/ReleaseNotes/UbuntuDesktop "Python 2.6 is no longer available for install".

I need to support legacy software that runs only on Python 2.6. How can I install Python 2.6 on Ubuntu 12.04?

My computer has an SD card slot. When I put a working SD card into the slot, nothing happens. When I put a CD or DVD in, or plug in a USB drive, the medium is mounted and available. Is there something special I need to do for SD cards?

Hardware specifics

I am running 11.10 on a Dell XPS L502X. The card slot is marked "SDXC/MMC - MS/Pro" (which Wikipedia tells me are various SD card types).

On occasion I receive forms to fill in as PDFs intended for printing (these are not true PDF forms, they do not contain fields). I would like to type onto them, and perhaps add a scanned copy of my signature. This way I could just email them back. Is this possible?

This morning my cat discovered a Nautilus feature I wasn't aware of. By sitting on my keyboard she split the Nautilus window into two panes. I am now at the office without my cat and unable to repeat the procedure. Is there a way to achieve this without a cat?

I've whitelisted some indicators for apps that don't yet have Unity-compliant appindicators. Is there any way to blacklist appindicators for apps that are Unity-compliant (not old-style indicators) but don't provide a "Don't show in the system tray" option?

• Any working solutions to ban an appindicator from being displayed, GUI- or CLI-based, are welcome.
• A valid alternative would be a way to hide the indicator in a similar fashion to how you can show/hide system tray icons in Windows 7. According to the answer to this closed question this is not currently possible in Ubuntu.
• Techniques that cover old indicators as well as new indicators are also valid. (Removing items from the systray-whitelist only works for old indicators.)

Let's assume I have a working application written in C, C++ or Python. I want to create a Launchpad PPA so others can easily install it from a package. Please give step by step instructions for doing this from beginning to end. (Or provide a link that does the same ;)

• Does the programming language matter? (Could it be a bash script?)
• Do I need to add anything to my build?
• Where should the build install itself to?
• How do I define dependencies?
• How do I use dependencies?
• How do I create a .deb?
• What do I need to do before uploading to Launchpad?