As per my comment on the question, mozilla provide some instructions for manually uninstalling.

  Manually uninstalling a plugin

  If you can't use an uninstaller program to remove a plugin, you can
  remove it manually:

  In the Location bar, type about:config and press Enter.

  The about:config "This might void your warranty!" warning page may appear. Click I'll be careful, I promise!, to continue
  to the about:config page.

  Search for the preference: plugin.expose_full_path.
  Double-click on the plugin.expose_full_path preference in the list to change the value to true.
  Enter about:plugins into the Location bar to display the About Plugins page.
  Each entry in the About Plugins page will have "File name:" followed by a path. Use Windows Explorer to navigateNavigate to the
  folder shown for the plugin you want to remove.
  Rename the file to something other than its normal name - e.g. npswf32 becomes Xnpswf32
  Double-click on the plugin.expose_full_path preference in the list on the about:config page to change the value back to false to
  avoid exposing the plugin path to websites.

  The plugin will be removed.

The above Mozilla.org community-contributed content is made available under CC-BY-SA 3.0, which permits properly-attributed derivative works distributed under the same license. CC-BY-SA is also the license that covers content here on Ask Ubuntu. Its formatting is changed very slightly to accommodate the StackExchange format. The page from which the above block-quote was taken lists Bo102010, cor-el, Verdi, and scoobidiver as contributing authors.


How do I get my graphic card to work properly?

I've also faced this kind of problem, I've uninstalled amd drivers removing all fglrx related in synaptic package manager and installed the brand new amd driver released on january 25th 2012 and everything works perfectly now, you should try:

http://support.amd.com/fr/gpudownload/linux/Pages/radeon_linux.aspx

regards


Simple and Low Resource games for Ubuntu?

I would suggest these following additional games for your low-spec computers:

Warmux: A turn based artillery game
Pingus: A Lemmings clone
Pysolfc: 1,000 Solitaire card games (what other games would you need??!)
Crack-Attack: A Tetris clone
Xmoto: A 2d motocross platform game

To install all of these with a single command try the following:

sudo apt-get install warmux pingus pysolfc crack-attack xmoto

I have tested all of these games and they seem entertaining enough and well suited to a low spec computer. Combined with your own suggested games they should give a great experience and a decent 'games pack' :)


is there a command to turn on keyboard lights?

This is what is in the sub directory:

 echo -n 0 > /sys/class/leds/phy0-led/
brightness      max_brightness  subsystem/      uevent
device/         power/          trigger


BACK UP using rsync Ubuntu server 16.04 Overall

I would recommend starting here
http://www.admin-magazine.com/Articles/Using-rsync-for-Backups/%28offset%29/2

There is also part 1 of this article with more background info. I think this is a very good intro to real life backup with rsync, I based my backups on that and I have been using that for over two years.


Thunderbird authentication failures after Firefox update

I have an update to this.  Since I posted the question, one of the two mail account hosts, in this case Yahoo, sent me an email saying there was a login from Thunderbird, which was me, and now that email account is fine. I still get authentication errors from the other host.  It appears this is not a Thunderbird or Firefox issue.


How do I install Java 6 for use in Chrome?

There is no way to install Java to Chrome at the moment. NPAPI plugins are not supported on linux any more. But I have not heard of any existing PPAPI Java plugins now.
I use Firefox for Java.


Since ubuntu 16.04 LTS Software Updater fails with dpkg: error processing package virtualbox-qt

There must have been some broken files that needs cleaning.
How did you uninstall virtualbox?
Try running the following command to clean install:

sudo apt-get autoremove
sudo apt-get --purge remove
sudo apt-get autoclean
sudo apt-get -f install
sudo apt-get update
sudo apt-get upgrade
sudo apt-get dist-upgrade
sudo dpkg --configure -a

If it still doesn't work afterwards, can you post the output of

dpkg --list | grep virtualbox-qt


First try refreshing your GUI by typing (CTRL+ALT+F7). If this doesn't work then try updating your computer from the TTY console. You can get to that by pressing (CTRL+ALT+F1). Login in with your username and password, then type

sudo apt-get update --fix-missing

This should fix any missing dependencies on your computer. When you are done, type

sudo shutdown -r now

to reboot your machine.

If any of this doesn't work, reinstall your LiveCD and reinstall Ubuntu.

Good Luck!


There's a command line method which might work for you:

CLI Method to Change Application & Set Default:

You can easily open a file with another application using the mimeopen command in the terminal. However, if the program isn’t already in the list of recommended applications, you’ll need to make it the default for that filetype first. Simply open a terminal in the folder where the file is and run a command like the following (substituting Recipes.pdf with the appropriate filename and filetype):

mimeopen -d Recipes.pdf

Please choose a default application for files of type application/pdf

1) GIMP Image Editor (gimp)
2) Adobe Reader 9 (AdobeReader)
3) Document Viewer (evince)
4) Other…

use application #4
use command: pdfedit

Simply choose the number that corresponds to Other… (in this case it’s 4), then type the command of the program after use command: (you probably won’t need to specify the path, but if it doesn’t work without it, it should be something like /usr/bin/pdfedit).

After that, you can switch default applications quite easily with the above command, or use the --ask option to just open the file in the desired app without changing the default (note there is no option to choose Other…, which is why you have to use the -d switch first):

mimeopen --ask Recipes.pdf

Please choose an application

1) pdfedit (pdfedit-usercreated-2)
2) GIMP Image Editor (gimp)
3) Adobe Reader 9 (AdobeReader)
4) Document Viewer (evince)

use application #


While the VLC is playing check on the Ubuntu sound properties in the application tab if the VLC volume it is deactivate from there or if it is in the lowest level.


MonoDevelop Google API GData assembly not found

Ok, I've found the problem, the libgdata1.7-cil is for the applications to work without the assembly useful for the development.

To be able to create an application that uses Google's API for C#, you need to download the libgdata-cil-dev, that you can find with synaptic.


Why use apt-get upgrade instead of apt-get dist-upgrade?

I typically upgrade my machines with:

sudo apt-get update && time sudo apt-get dist-upgrade

Below is an excerpt from man apt-get. Using upgrade keeps to the rule: under no circumstances are currently installed packages removed, or packages not already installed retrieved and installed. If that's important to you, use apt-get upgrade. If you want things to "just work", you probably want apt-get dist-upgrade to ensure dependencies are resolved.

To expand on why you'd want upgrade instead of dist-upgrade, if you are a systems administrator, you need predictability. You might be using advanced features like apt pinning or pulling from a collection of PPAs (perhaps you have an in-house PPA), with various automations in place to inspect your system and available upgrades instead of always eagerly upgrading all available packages. You would get very frustrated when apt performs unscripted behavior, particularly if this leads to downtime of a production service.

upgrade
    upgrade is used to install the newest versions of all packages
    currently installed on the system from the sources enumerated in
    /etc/apt/sources.list. Packages currently installed with new
    versions available are retrieved and upgraded; under no
    circumstances are currently installed packages removed, or packages
    not already installed retrieved and installed. New versions of
    currently installed packages that cannot be upgraded without
    changing the install status of another package will be left at
    their current version. An update must be performed first so that
    apt-get knows that new versions of packages are available.

dist-upgrade
    dist-upgrade in addition to performing the function of upgrade,
    also intelligently handles changing dependencies with new versions
    of packages; apt-get has a "smart" conflict resolution system, and
    it will attempt to upgrade the most important packages at the
    expense of less important ones if necessary. So, dist-upgrade
    command may remove some packages. The /etc/apt/sources.list file
    contains a list of locations from which to retrieve desired package
    files. See also apt_preferences(5) for a mechanism for overriding
    the general settings for individual packages.


Fujitsu lifebook ah552 touch pad sensitivity and side scrolling problem

Steps

Find the device name

xinput list

in my case it is
AlpsPS/2 ALPS GlidePoint

then find the current values for the device

xinput list-props "AlpsPS/2 ALPS GlidePoint" | grep -i finger

In my case it was 12, 15, 0

next we have to change the values as per below

12, 12, 0

for that we can use below command

xinput set-prop "AlpsPS/2 ALPS GlidePoint" "Synaptics Finger" 12, 12, 0

Now the touch pad will be normal and also side scrolling should be working.

Finally we have to save the changes permanently, other wise this will not work after rebooting.

Create a bash file

sudo nano /usr/bin/fujitsu-lifebook-ah552-alps-touc-pad-settings.sh

the first line of the text should be this

#!/bin/sh

and after two line paste the command we previously used for changing the values.

xinput set-prop "AlpsPS/2 ALPS GlidePoint" "Synaptics Finger" 12, 12, 0

save the file using shortcut ctrl+o, then exit ctrl+x

make the file executable

sudo chmod a+x /usr/bin/fujitsu-lifebook-ah552-alps-touc-pad-settings.sh

That's all! Do not forget to reboot the machine!

Disable two finger scrolling on mouse setting to enable side scrolling.


How I Can Create A Launcher For a Program

Create a file in /home/$USER/.local/share/applications/firefox-custom.desktop, and add the follow lines of code:

[Desktop Entry]
Version=1.0
Type=Application
Name=Firefox Quantum Edition
Icon=/path/to/mozicon128.png
Exec=/path/to/executable/firefox %u
Comment=Firefox Custom 56
Categories=Development;IDE;
Terminal=false

With this when you search for it in dash you will see two launchers on for the 57 version in /usr/bin/firefox and the other for 56 custom in /usr/local

Note (confirm and adjust accordingly):

Icon location would be: /usr/local/firefox/browser/icons
Executable location would be: /usr/local/firefox


Hard Disk Partitioning during 12.04 Install

Try switch the SATA mode in the BIOS from IDE to AHCI. You can plug HDD to another connector on the motherboard. And try this sudo fdisk -l under installation in terminal.


Force Pidgin to acept an invalid certificate

As alternative you can download the ssl certificate by hand. Afterwards pidgin starts without problems.
To download the certificate you can use openssl command line utility.

~/.purple/certificates/x509/tls_peers$ openssl s_client -connect YOUR_SERVER:PORTNUMBER

When the above command fails with "no peer certificate available" then maybe the server uses STARTTLS instead of SSL. In this case use the following command:

~/.purple/certificates/x509/tls_peers$ openssl s_client -connect YOUR_SERVER:PORTNUMBER -starttls xmpp

Now copy the part beginning with "----BEGIN CERTIFICATE----". If you print the content of the certificate file it looks like the following:

~/.purple/certificates/x509/tls_peers$ cat jabber.ulm.ccc.de

-----BEGIN CERTIFICATE-----
MIIFXDCCA0QCCQCa5jxvwccm0DANBgkqhkiG9w0BAQUFADBwMQswCQYDVQQGEwJE
RTEMMAoGA1UEBxMDVWxtMRUwEwYDVQQLEwxDQ0MgRXJmYSBVbG0xGjAYBgNVBAMT
EWphYmJlci51bG0uY2NjLmRlMSAwHgYJKoZIhvcNAQkBFhFqYWJiZXJAdWxtLmNj
...
3EIpMVk3V1djyj0FEuDaG/o+6BTLCiIMiIUFtbpVz8YZChHbv8ObMJ5JpUIkDfKZ
si1YZKpUYwpVXgTCUml67lArx/sq95OQsDSO3fR1Ch0=
-----END CERTIFICATE-----


You're asking a lot of questions, but I will try to fit all the answers into one.

Do you need a / (root) partition? Yes.
Do you need a /home partition? No. You may create one, but I don't see a requirement for one (from what you've written).
Do you need a swap partition? No, this is not strictly needed, but I would suggest that you make one.
Do you need a final partition for data for both XP and Ubuntu to see? This is not required if all you need is to be able to share files between the two operating systems. Ubuntu comes with a fine NTFS driver that will allow you to read and write from the partition Windows XP is installed on. If you would like to share data between the two on the second drive, then yes this is needed.

Should the data partition be formatted FAT? You might as well format it NTFS, as it allows for larger individual files and can works fine from Ubuntu.

What sizes should you use? This one is rather hard. I'd make the swap partition about the same size as the amount of memory the machine has. If making the data partition, you will need to decide how much space you want to reserve for both operating systems. You can make your root partition (in this case your only 'linux only' partition) as little as 10GB (even smaller if you want), but I'd recommend at least 20 or 30. It really depends on your needs.


Ubuntu LTSP 18.04 lock screen not accepting password

I had the same problem and after a lot of time, I was able to figure it out. The problem is that the /etc/passwdfile is missing on the clients. This is how I solved it:

I installed LTSP in chroot mode (can be done after chrootless installation):

sudo ltsp-build-client

Execute this command on the server.
Once that‘s done, enter:

sudo ltsp-chroot

to switch into the clients' file system. Then install a desktop environment of your choice.
Use the following command to create a user:

useradd NAME -m -s /bin/bash

If you want to, you can allow sudo usage for that user.
Type exit to quit the chroot.
Execute

sudo ltsp-update-image

The problem should have been solved.

Note: This method will erase all of the client data, you have to reinstall everything!


32 or 64 bit, which one is suitable for 3GB RAM but legacy specs?

Your processor is 64 bit with 4 cores, you have enough memory to comfortable work, so why not to install 64 bit system ? You definitely should try it. You will be satisfied with performance of ubuntu 14.04 64 bit


Compiling and running Java code - NoClassDefFoundError

The correct way of compiling java code in your case is

javac Code.java

and then run using

java Code


Assuming you are using the gnome-shell you can configure it to Have file manager handle the desktop. This way the desktop is managed by nautilus and your gestures should be recognized.

The easiest way to configure this is to use Gnome Tweak Tool.

sudo apt-get install gnome-tweak-tool

Launch Gnome Tweak Tool from the Gnome Shell menu. It will be called Advanced Settings. Then, click on the Desktop button. Enable the option that says "Have file manager handle the desktop. Now, any files placed in the Desktop folder inside your home folder should appear on ther desktop.

As I'm lazy the former paragraph was taken from:
https://askubuntu.com/a/105988/233113
Just changed the formatting and stripped the image.

If you want to use (three finger) scrolling to switch desktops, I remember there was a setting someday, I recommend using the touchegg action called CHANGE_DESKTOP. If you use SCROLL it will scroll on any windows.


Basic Apache2 question regarding pointing to a new conf for /var/www/mySite.com

You can either edit the /var/www/html/index.html file or edit your conf to point to the dir of your pages.
You don't need an .htaccess file.
Make sure you restart apache:

## Start command ##
systemctl start apache2.service

## Stop command ##
systemctl stop apache2.service

## Restart command ##
systemctl restart apache2.service


Can't boot into ubuntu after remove window7

It could be that your Partition table is bonked.

Try using Testdisk with a live cd

http://www.cgsecurity.org/wiki/TestDisk

To reconfigure grub from a live cd, use this excellent HOWTO

http://ubuntuforums.org/showthread.php?t=1581099


12.04 gnome classic ambiance font problem

The bug is reported https://bugs.launchpad.net/ubuntu/+source/light-themes/+bug/981289 and a fix is available in a branch on Launchpad, but it hasn't been merged yet, so it's not available in the official Ubuntu 12.04 repositories.

A solution is to use the fixed "light-themes" (Ambiance and Radiance) package available in the WebUpd8 themes PPA. Add the PPA and upgrade to get the package using the commands below:

sudo add-apt-repository ppa:webupd8team/themes
sudo apt-get update
sudo apt-get upgrade

Reference


I solved it by just deleting the 21 version Snap via Software manager, and v24 that was installed from PPA stayed.


15.04 and newer:

Use this command:

sudo systemctl restart ssh

To restart the SSH server/daemon.

Going forward with systemd starting with Ubuntu 15.04, you now use this syntax to stop, start, or restart services:

sudo systemctl <action> <service-name>


USB flash drive partitioning exits without completing

It seemed like the fat32 partition had problems.
1. I copied the data from it to my hard drive.
2. I created a new msdos partition table.
3. I created 2 new partitions.
4. Copied the files back to the first partition again.
Now it works without having any problems.


Fixed by re-installing windows on GPT SSD in UEFI mode.

And my BIOS was automatically disabling windows boot manager when I installed linux on drive #2. So re-enabling that basically fixed the problem.


how to To set your Squid server to listen on TCP port 8888

You can read the detailed documentation regarding installation/configuration of Squid.

Prior to editing the configuration file, you should make a copy of the original file and protect it from writing so you will have the original settings as a reference to re-use as necessary.

sudo cp /etc/squid/squid.conf /etc/squid/squid.conf.original
sudo chmod a-w /etc/squid/squid.conf.original

You should now edit (ex. sudo nano /etc/squid/squid.conf) the file /etc/squid/squid.conf and change the http_port directive to http_port 8888


Trigger if directory size exceeds threshold

If you want to have periodic check, say on every restart or every Tuesday of the month, you could set up a cron job, that calls your backup script, and you could check the filesystem usage within your backup script itself. Can be done simply like so:

if [ $(df / --output=pcent | awk -F '%' 'NR==2{print $1}') -ge 80 ] ;
then
   # do something here
fi

That basically  calls df command with output limited to percentage use and / filesystem , and trims the output so that only percentage is returned. If  percentage is greater or equal to 80 , it would execute whatever you place after the # do something here  comment.

If you want continuously running solution , here's a Python script that checks your filesystem usage every 0.25 seconds. I've written a simple wrapper function for subprocess.check_output , so you can use that to easily place call to your script there in form of a list of strings ( which is basically this: ['brackets', 'and' , 'quotes']  )

#!/usr/bin/env python
import subprocess
import time
import sys

def run_cmd(cmdlist):
    # function for running
    try:
        stdout = subprocess.check_output(cmdlist)
    except subprocess.CalledProcessError:
           pass
    else:
        if stdout:
            return  stdout

fs_usage = ""

while True:
    fs_usage = run_cmd( "df / --output=pcent".split() )
    if int(fs_usage.split("\n")[1].strip().split("%")[0]) >= 80 :
        # make call to your backup script here !
        # Use list format
        run_cmd( [ 'notify-send','Hello','World'  ]  )
        sys.exit(1)
    time.sleep(0.25)


lubuntu live session in installation ISO

Is there a live session on lubuntu installation ISO so I can test it ?

Yes. If you have an ISO image for Ubuntu or any of its official derivatives, and if -desktop- appears in its filename (e.g., lubuntu-14.04.1-desktop-amd64.iso), this means it is a live ISO image that contains:

a usable live desktop interface, with which you can test and otherwise use the OS without installing, and
a utility called Ubiquity (better known as "Install Ubuntu" or, in this case, "Install Lubuntu") that will, when run, provide an interactive, graphical installation of the OS.

When you boot the CD/DVD/USB created from the ISO image, you're asked if you want to try or install the OS. If you select to install it, Ubiquity will run immediately. If you select to try it, you'll get a functioning live desktop, and you can either run Ubiquity or not after that.

The live desktop of an official Ubuntu derivative contains the programs that are installed by default in that derivative. This always includes a web browser, word processor, and various other applications.


Answer for main question:

This simple script run on session startup then it launches vnc server which starts new session and in this session upstart launches this script again. So many instances of Xvnc called recursively. I made some additions to script:

start on startup

script
if [ -z "$(ps -e | grep Xvnc)" ]; then
    /usr/bin/vncserver
fi
end script

now it works fine and brings up only one session.

segfault error still exist but main problem is solved.


After forcefully shut down ,it was unable to start

Have you tried looking inside BIOS whether the hard disk is listed there?? If not, please check and let us know first. Usually it should be F12 or a specified key will be shown at the POST screen while booting.


Why can't I run this executable file (.exe) in Octave?

type the below commands

system('echo $SHELL');
system('echo $LD_LIBRARY_PATH');

and see if they look the same as typing echo in your Ubuntu terminals, if they are not the same, likely you started your octave from a launcher, which starts a non-interactive shell instead of an interactive shell (these cases, they have different rc files, see https://unix.stackexchange.com/a/170499/366890). you can at least run

system('LD_LIBRARY_PATH=/path/to/liblapack.so/folder ./executable.exe')

alternatively, find the correct rc file and add the path to LD_LIBRARYPATH in that environment.


How to run SUDO... commands in cronjobs in Ubuntu 16.04?

Simply run crontab -e as root user . This would run your command with root permission and there is no need to add  sudo before it .

However you can't login with root user and you need to perform your job as cron job you should specified full path in cron file :

 $ * * * * * /usr/bin/sudo /your/command

Also you can add NOPASSWD in front of your command in /etc/sudoers file to run command as root but without password .


If df it's not enough, you can try GParted.

You may want to see also:

How to remove Ubuntu and put Windows back on?


Chromium/Opera "randomly" not rendering in i3

In my case, it turned out that something was wrong with the GPU renderer of the browsers

After apparently another 2 months after posting the question and inspecting various scenarios, I still haven't figured out why it happens, but I've figure out how to fix it once it happens.

When one of your chromium-based browsers freezes/disappears like that, look for a process with --type=gpu-process under either opera, chromium, or what have you, then kill it

$ ps aux | grep opera | grep gpu-process
user      9736  1.8  1.4 613716 115176 ?       Sl   Jan09  26:35 /usr/lib/x86_64-linux-gnu/opera/opera --type=gpu-process --field-trial-handle=...
$ kill 9736

Some tabs might be affected, and display an error, but simply refreshing them makes the browser work again


lame cannot read in filenames from input. You will have to use find's -exec or xargs to run it over each file found:

find . -iname '*.mp3' -exec lame -b {} \;

If a second filename isn't specified, lame will attach another .mp3 to the given filename and write to that file. lame does not support writing to the same file. You'll have to convert to another file, then copy it over the original file:

find . -iname '*.mp3' -exec sh -c 'lame -b 160 "$0" "$0"-160 && mv "$0"-160 "$0"' {} \;


How can I transfer a binary file using minicom and a serial connection?

I have not tried this before, but this page says you can send binary via minicom by encoding it in ASCII. You need to have busybox installed on the box.

Use uuencode to encode. Here is it's syntax:

uuencode [INFILE] STORED_FILENAME > send_file

INFILE is the path to file to encode and STORED_FILENAME is obviously the name of the file. uuencode outputs to stdout, so it is redirected to a temporary file, send_file.

Ready the target machine for recieving file:

target$ cat > recieved_file

Now it is uploaded as ascii using minicom:

host$ minicom
CTRL+A S
+-[Upload]--+
| zmodem    |
| ymodem    |
| xmodem    |
| kermit    |
|>ascii<    |
+-----------+

On the target, decode the file:

uudecode [-o OUTFILE] [INFILE]

To see if it worked as expected, check md5:

busybox md5sum <filename>

Please see if this works and post back, because I have never done this. myself


Are there any tilling desktop environments (not window managers)

You don't necessarily need a desktop environment for that. You can just --replace the existing WM of the desktop environment currently in use but some DEs are a bit picky.

XFCE works perfectly in this case, install XFCE and then install the WM of your choice for instance compiz and then just add a startup script with one command: compiz --replace (if you were running compiz).

If compiz is not the one you want to use then look through the --help menu of the chosen WM to find the equivalent flag for --replace.

Before adding a start-up script, test it from a terminal. Here are some commands that you can use with XUbuntu:

sudo apt update
sudo apt install compiz-core
compiz --replace

If that works, create a new ASCII file and call it replace-wm with the following contents:

#!/bin/bash
compiz --replace

Then make the file executable:

chmod u+x replace-wm

Then using XFCE's Session and Startup settings, add the path of replace-wm as a startup script.


How to completely restore default desktop environment in ubuntu 14.04 lts after installing and removing gnome desktop environment.

Completely remove the GNOME desktop and reinstall the Unity desktop from a virtual console.

Boot the PC - on login screen press Ctrl+Alt+F1 - enter user name and password - execute :

sudo apt-get purge gnome
sudo apt-get update
sudo apt-get install --reinstall ubuntu-desktop
sudo reboot

Although restarting the system isn't strictly necessary, it nevertheless is recommended to do so.


Yakuake settings not being applied in 18.04

It seems clear to me that this is a bug.  There are no fewer than 3 bug reports for this issue, going back to January 2015:

https://bugs.kde.org/show_bug.cgi?id=343434

https://bugs.kde.org/show_bug.cgi?id=374504

https://bugs.kde.org/show_bug.cgi?id=383555

This affects me as well, and I have just commented on the oldest bug report.


Wanting to Install Ubuntu, currently have Windows, don't want to lose files

First of all, Try Ubuntu with a liveCD or liveUSB. To see if it works with your laptop. because sometimes you may end up with a black screen.

Second thing, Try to back up your data. I know you don't have any external storage. But try to find one. To tell you the truth I don't back up my data. Even when I installed Ubuntu for the first time. Because the installation process is really simple. all you have to do is to click on "Install alongside windows" option and it will automatically adjust it for you.

Now, if you want to select the "advanced option". At that time you should really consider backing up your data.


Backporting Qt 4.8.4: Circular dependencies of qtchooser

It turns out that in this specific case what I had to do is:

Create a new, empty PPA and get launchpad to build qtchooser there first, so it builds against the Precise version of libqt4-dev
After qtchooser is built add qt4-x11 so the latest libqt4-dev is built
Rebuild qtchooser again against the latest libraries
Continue to add the other packages to the ppa


How to activate VirtualBox USB devices support?

The package virtualbox-ose available in the repositories does not include support for USB.

You will need to uninstall that and get the version from Oracle.
https://www.virtualbox.org/wiki/Downloads


create a file and put smth like

#!/bin/bash

useradd "$1" && gpasswd -a "$1" group

in there.


Someone on wolfire's forums, posted this solution:

  The problem with lugaru and sound with pulseaudio is the bundled versions of the sdl and al libraries (libsdl.so.1 and libal.so.1), they are either too old or not compiled with pulseaudio support. Fortunately they are binary compatible with the ones probivided by ubuntu so if you simply remove those two files you will force Lugaru to use the system versions and you will have sound.

Delete libal.so.1 and libSDL-1.2.so.0 (note the slightly updated names) from the lugaru directory, and the sound plays in perfect "HD".


Install python setup tools for Ubuntu 12.04

The simplest option to try out Savanna is to use devstack in a virtual machine. I was using an Ubuntu 12.04 virtual instance in my tests. In that environment we need to execute the following commands to install devstack and Savanna API:

$ sudo apt-get install git-core
$ git clone https://github.com/openstack-dev/devstack.git
$ vi localrc  # edit localrc
ADMIN_PASSWORD=nova
MYSQL_PASSWORD=nova
RABBIT_PASSWORD=nova
SERVICE_PASSWORD=$ADMIN_PASSWORD
SERVICE_TOKEN=nova

# Enable Swift
ENABLED_SERVICES+=,swift

SWIFT_HASH=66a3d6b56c1f479c8b4e70ab5c2000f5
SWIFT_REPLICAS=1
SWIFT_DATA_DIR=$DEST/data

# Force checkout prerequsites
# FORCE_PREREQ=1

# keystone is now configured by default to use PKI as the token format which produces huge tokens.
# set UUID as keystone token format which is much shorter and easier to work with.
KEYSTONE_TOKEN_FORMAT=UUID

# Change the FLOATING_RANGE to whatever IPs VM is working in.
# In NAT mode it is subnet VMWare Fusion provides, in bridged mode it is your local network.
FLOATING_RANGE=192.168.55.224/27

# Enable auto assignment of floating IPs. By default Savanna expects this setting to be enabled
EXTRA_OPTS=(auto_assign_floating_ip=True)

# Enable logging
SCREEN_LOGDIR=$DEST/logs/screen

$ ./stack.sh  # this will take a while to execute
$ sudo apt-get install python-setuptools python-virtualenv python-dev
$ virtualenv savanna-venv
$ savanna-venv/bin/pip install savanna
$ mkdir savanna-venv/etc
$ cp savanna-venv/share/savanna/savanna.conf.sample savanna-venv/etc/savanna.conf
# To start Savanna API:
$ savanna-venv/bin/python savanna-venv/bin/savanna-api --config-file savanna-venv/etc/savanna.conf

Source.


This happens when the user directories and permissions are not set correctly. In order to fix it, I used the following:

sudo useradd myusername
sudo passwd myusername

Then try sending mail by terminal mailutils to this user, so that necessary folders are made automatiacally, then continue with setting permissions:

sudo mkdir -p /var/www/html/myusername

usermod -m -d /var/www/html/myusername myusername

Now the important part:

sudo chown -R myusername.myusername /var/www/html/myusername

usermod -m -d /var/www/html/myusername myusername

now trick of the trade: send a mail to this user using the mailutils command:

root@server-name:/$ **mail myusername@**

...

This automatically creates a folder in /var/mail for that user and the next time you login, everything works fine.

Now, you can login. If you encounter further problems, edit the dovecot.conf file and then restart the dovecot. But I don't anticipate any problems after this.


how to permanantly change boot order in UEFI os manger list?

i found this post on the HP support forum, it is not particular to HP as it doesn't depend on hardware in any step.

so the steps are as follows:

1- In Windows , run cmd.exe as an administrator

2 -mount the UEFI partition using : mountvol X: /S

change X with a drive letter of your choice

2- now kill the explorer and re-execute it, using

Taskkill /F /IM explorer.exe
explorer.exe

3- the new mount new mount partition should appear in the "My computer" window
    go to X:\EFI\Microsoft\Boot\ where X is the the Drive letter you specified before, and rename the file bootmgfw.efi to something like bootmgfw.efi~
and remove the file X:\EFI\Boot\bootx64.efi.

4- in the command prompt execute

bcdedit /set {bootmgr} path \EFI\Microsoft\Boot\[FILENAME]

note that this require administrative rights and the name of the FILENAME is to be adapted with previous renaming, in this example it is bootmgfw.efi~

5- to make things clearer, you can change the Windows Boot loader to something like "Fixed Windows path" with the command

bcdedit /set {bootmgr} description "Fixed Windows path"

6- on Ubuntu, Use efibootmgr to delete the "OS boot Manager" entry:

sudo efibootmgr -b 0000 -B

7- use sudo efibootmgr -l to learn the id of each UEFI boot menu entry if you had ubuntu on boot0001 and windows on boot0002 so proceed like this

sudo efibootmgr -o 0001,0002

8- use  sudo gedit /etc/grub.d/40_custom and add the following block in the file

menuentry "Microsoft Windows 7" --class windows --class os {
        insmod part_gpt
        insmod fat
        insmod search_fs_uuid
        insmod chain
        set root='XXXXXX'
        chainloader /EFI/Microsoft/Boot/[FILENAME]
}

where XXXXXX is the output of sudo grub-probe -t drive /boot/efi/EFI/Microsoft/Boot/[FILENAME]

and FILENAME is the efi file name, in this example it is bootmgfw.efi~

9- finally sudo update-grub to apply the changes , after reboot you should see the windows in the list while booting to Ubuntu by default via Grub.


How to extract multiple .7z files with password? (GUI preferred)

Not a GUI solution but command line:

find . -name *.7z -type f| xargs -I {} 7z x -ppassword {}

Where -ppassword means that "password" is your password.


Boot manager disappeared after rolling back Windows to a previous version

That is because your boot manager (chances are that it is GRUB2) went south from the MBR.

You need to boot from your Ubuntu installer in "live CD" (try without installing) mode, then open a terminal, get a root shell, and chroot yourself in your installation before you can run grub-install.

For that, mount your hard drive (presumably /dev/sda2 or /dev/sda3) somewhere (for the sake of the least resistance, let it be straight /mnt).

After that, mount the necessary file systems:

# mount -o bind /proc /mnt/proc

# mount -t sysfs /sys /mnt/sys

# mount -t proc /proc /mnt/proc

Finally chroot into your installation:

# chroot /mnt /bin/bash

Now you need to reinstall grub with the same parameters:

# grub-install /dev/sda

Mind that you need to specify the device itself, not the partition (e.g. no /dev/sda3 but /dev/sda) when installing grub to MBR.

Now you are done, you can reboot and boot Ubuntu.


Use nbd, the Network Block Device, and then rate limit access to it using say trickle.

sudo apt-get install nbd-client nbd-server trickle


No currently supported way. You could stop it from running or trick it to run menus inside the apps, but both are rather hackish.

My best advise is get used to pressing alt. Your "not supposed" to access menus with the mouse anymore, just press alt and say what you want it to do.

For example press alt and type save. However I find that personally very cumbersome for menu items I don't already know about.


How do I set a VLC instance to run as a Live Wallpaper

VLC does support video as background. Simply run the cvlc command:

cvlc --video-wallpaper --no-audio /your/videofile

There are other helpful options to cvlc such as aspect ratio etc. You can find them using

vlc --help

If you still want icons on your desktop you may need to take a look at xwinwrap, but it requires a little digging. There is an option to set movies as background. I dont know how to do it with VLC but it has been done with mplayer.


Ubuntu Server 14.04.1 Boot loader Not Showing Up

I have determined that this was an issue with the motherboard and not with Ubuntu Server. I had tried many settings on the BIOS to get it working (UEFI on/off fast boot on/off, secure boot on/off), but nothing worked. When I took the drive to my main computer, it worked perfectly on my newer Asus motherboard. I guess this Intel board doesn't like 4TB hard drives.


How do I get MonoDevelop 2.8 with Mono 2.10?

You can remove the version of monodevelop installed through Ubuntu's software sources, download the source code archive for monodevelop 2.8 upstream (http://monodevelop.com/Download), and build and install the source manually. See https://help.ubuntu.com/community/CompilingEasyHowTo for general advice on building software from source.


How do I change the behavior of the Nautilus popup search box?

It looks like this is a known issue and a fix is in progress. Let's hope it is released soon!


Where are Dia diagram shapes located on Linux?

How to find specific files, installed by applications

Found them on Ubuntu 16.04 in /usr/share/dia/shapes. Ubuntu or Lubuntu  shouldn't make a difference. You can find out where files are installed with the help of

dpkg-query -S .shape

to look for specific patterns. This shows that all .shape files are in /usr/share/dia/shapes. They are grouped however in many subdirectories.

Note however that for each and every .shape file, there is a corresponding .png file, most likely to represent the shape in the menu:

See also man dpkg-query

   -S, --search filename-search-pattern...
          Search  for  packages  that own files corresponding to the given
          pattern.  Standard shell wildcard characters can be used in  the
          pattern,  where  asterisk (*) and question mark (?) will match a
          slash, and blackslash (\) will be used as an escape character.

          If the first character in the filename-search-pattern is none of
          ‘*[?/’  then it will be considered a substring match and will be
          implicitly surrounded by ‘*’ (as in  *filename-search-pattern*).
          If  the  subsequent  string contains any of ‘*[?\’, then it will
          handled like a glob pattern, otherwise any trailing ‘/’ or  ‘/.’
          will be removed and a literal path lookup will be performed.

          This  command  will  not  list extra files created by maintainer
          scripts, nor will it list alternatives.

To find out where an application installed its files, use (in this case):

dpkg-query -L dia-shapes

Finding out with synaptic

Also Synaptic offers help how to find out.

Search for `dia, right-click on the package
Click on "Installed Files" (tab)


Is installing another desktop environment on a stock Ubuntu 20.04 install consider reasonably safe/ok. Low risk for serious issues

I've done it for years and never had problems with two desktops.
My existing install was a Ubuntu artful (beta) with default GNOME desktop (ie. ubuntu-desktop). On it I added

xubuntu-desktop (XFCE)
ubuntu-mate-desktop (MATE)
lubuntu-desktop (LXDE)

I also wanted to have kubuntu-desktop, but that created problems I was unable to resolve.  I installed the desktops many times to work out the order I needed for all four to co-exist the happiest, then wiped my system & re-installed in the order I'd calculated was best.
That system is now groovy (what will be 20.10, though I'll bump to H a day or so post-release anyway).  I've also removed the ubuntu-mate-desktop (running low on disk space mostly), so now I only have GNOME/XFCE/LXQt (Lubuntu switched from LXDE to LXQt)
I have installed desktops on most my systems, and in my experience I'll offer the following

first additional desktop; expect no issues, no risk in my opinion

second additional desktop; expect no issues, extremely minor risk

third additional desktop; minor problems should be expected, and order of desktop install seems to matter

fourth additional desktop, expect problems & desktop install order matters

fifth desktop; good luck!  (easier on debian or opensuse for some reason)

Costs

extra bandwidth for downloads, as you'll have more packages requiring upgrading
release-upgrade requires more disk space, as more upgraded packages to download, unpack & then install, before the disk space can be re-claimed
upgrades etc take longer due to extra packages
more complex menus, as my own system has as editors "Featherpad" (LXQt), "Mousepad" (XFCE) .... etc and that occurs for nearly every application.
you're likely to use programs intended for one DE on a different DE, and the visual effects may mean a less cohesive experience to a single desktop install; subjective
make changes to settings in one (Budgie for example in your question) and you may find it changed GNOME too (due to shared toolkits/libs/settings)

Is it worth it - in my opinion for sure.  If I decide my expected workflow on a day will be best with GNOME/Ubuntu, I can select it at login. My other choices are XFCE/Xubuntu or LXQt/Lubuntu (MATE until I removed it).  I can also just use a different desktop for a change when I feel like it.
This is based on my experience, and maybe considered opinion. (I've multiple machines, and I think all have multiple desktops installed)


Want to make VSCode always start with `--disable-gpu` option, from everywhere, e.g. gnome dock

Find *.desktop file and edit it.
The file should be ~/.local/share/applications/ or /usr/share/applications/

Add parameter to the line Exec=


How to set default folder view to “list”, in Ubuntu

Open the files app, Click on this icon in the top right corner, now it's showing that icons view is selected (the blue grid button) select the button right to it (which displays lists icon). and folders and files will appear in lists


Mostly it will work perfectly. Linux is not windows. Many drivers are included, when you tick the checkbox " install drivers while installing Ubuntu"


Can't install libxi-dev and libxmu-dev on Ubuntu 16.04 because of unmet dependencies

You can install them using aptitude. It will suggest you different solutions to resolve the dependencies. Accept the one that downgrades the packages on which libxi-dev and libxmu-dev depend.

First, install aptitude:

sudo apt install aptitude

Then, install your packages using aptitude:

sudo aptitude install libxi-dev libxmu-dev

The first solution will be:

     Keep the following packages at their current version:
1)     libxi-dev [Not Installed]
2)     libxmu-dev [Not Installed]

Accept this solution? [Y/n/q/?]

Do not accept this solution. This will simply not install your packages. Enter n.

The next solution will be:

     Downgrade the following packages:
1)     libxi6 [2:1.7.6-1 (now) -> 2:1.7.5-1 (xenial)]
2)     libxmu6 [2:1.1.2-2 (now) -> 2:1.1.2-1ubuntu1 (xenial)]

Accept this solution? [Y/n/q/?]

Enter y to accept this solution. This will downgrade libxi6 and libxmu6, and then install libxi-dev and libxmu-dev.


Is it possible to make a file that has full permissions for everybody but is impossible to delete?

No, this is not possible. Impossible for normal users to delete a file: sure.

You will need sudo to prevent users to delete files. Your administrator will -always- be able to delete a file.
sudo chattr +i test can prevent deletion but does requires sudo. A simple sudo chattr -i test makes it possible to remove the file. No other user than admin can use chattr.

And... simply rebooting and going into rescue mode will allow that person to be able to delete that file. It would be a security risk if there was a method to never be able to delete a file.


How do I tell which is the visible window if there are multiple similar windows

One possible solution is to use the GNOME shell extension Window List. It displays a list of windows at the bottom of the screen and also greys out minimised windows.

For example in the screenshot below there are four Nautilus windows open, with first two being minimised.

(note that it also puts square brackets around the minimised window title)

Refer to this for installing and managing GNOME extensions: How do I install and manage GNOME Shell extensions?


How to fix EXT4-fs error even after a full wipe?

Back up your important data now.  This may be a hardware error, if not on the disk,maybe on the controller.  This sounds like the early stages of a (thermal induced) problem of solder pads cracking on the controller chip.  If you can get an external disk enclosure, mount your disk in it, and boot from that, maybe the errors will not occur.  If your enclosure works on another laptop, but not yours, the controller may still be at fault, but the fix then is to either replace the motherboard (since the controller is soldered on), or try a really hard re-melt with a heatgun of the chip solder pads.
  Do watch your temperatures (lm-sensors package), and consider an external cooler/fan for the laptop.  Avoid things which heat the machine up, like maybe  streaming video or playing games.  I've tried the heatgun on several motherboards, but never got it to work.  My problem was an Nvidia controller chip, which was almost as big as the CPU, but didn't even have a heat sink!  After three motherboards dying a slow death (first the disk, then months later the usb or wireless), I gave up on that machine.


When the Computer starts, after loading the BIOS, it boots from a Operating System Source which can be Hard drive ,USB drive, Ethernet or DVD/Floppy Drive. The order in which these source should be checked if there is any Operating System installed on them or not, can be changed from Boot Order in BIOS settings.

If you have two Operating Systems on one Hard Drive and you wish to select which one to use every time you turn on your computer,that's where Boot Manager comes into action. Boot Manager identifies all the installed O.S. on the Hard Drive (or some other source like USB, DVD etc. for that matter) and gives the user choice to choose one.

Here, since you have two Hard Drives (one SSD and other HDD), you actually have two sources to boot from and hence there is no role for Boot Manager. So if you want to choose a particular Hard Drive each time your computer starts, you have select from Boot Device Options each time (either by pressing Esc or F12 or something else depending on your computer).

Hope that helps.


Does ubuntu apt eliminate the need of backporting (as described by RedHat)?

It's not really about apt, but packages in the Main repository do get backported security fixes throughout the life-cycle of an Ubuntu release. So if you stick to this software, then you won't have to do anything special except install updates as they become available.

The only two exceptions I'm aware of, is Firefox and Thunderbird, which instead of getting backported fixes, are instead upgraded to a newer version.

In other words; the document you refer to, pretty accurately describes what happens in Ubuntu.


00df device isn't included in the list of supported devices in wacom_wac.c, check the the post:

Appendix 3: BambooPT models released October 2011 (DD,DE,DF) - Natty (11.04) or later

Instructions in the post are a bit contradictory but I finally have the wacom tablet working after downloading wacom-bamboo.tar.gz and unzipping the contents into 2.6.36 in the latest gitcheckout of the input-wacom folder. Downloaded wacom-bamboo.tar.gz from

Re: [Linuxwacom-discuss] New Bamboo Tablet Testers Needed From: Chris Bagwell - 2011-10-09 20:082

after build, move wacom.ko to the lib/modules/ folder.

wacom is now active, but a warning, there are more diffs between the wacom_wac.c code than just support for the usb device used. How to correctly merge the code changes is not obvious to me. Guess I'm up to new "happy" surprises.


Maybe it isn't designed to run in background.

Yes, it is. The wiki shows methods running it as a daemon and as a scanner:

  Run ClamAV as a Daemon

  Install clamav-daemon. You can then use clamdscan where you would
  previously have used clamscan. Lots of programs, especially e-mail
  servers, can connect to a ClamAV daemon. This speeds up virus scanning
  as the program is always in memory.

  The clamav-daemon package creates a 'clamav' user; in order to allow
  ClamAV to scan system files, such as your mail spool, you can add
  clamav to the group that owns the files.

  Let ClamAV listen for Incoming Scans

  There are cases where you may want ClamAV daemon to act as a scanner
  for other systems, so you don't have to run everything locally on the
  system.

  To do this, you simply have to modify the clamd.conf file and add
  TCPSocket PORTNUMBER and TCPAddr IPADDRESS arguments to the clamd.conf
  file and reload the daemon. The daemon will then accept connections to
  it via the IP address and Port combination you specify.

  I just want good protection for my system.

Linux is fundamentally different from Windows so we did not inherit the problems Windows (still) faces. Our system has been set up as a multi-user system: more than 1 user at the same time is expected to use it. This means we have a security model built into our system since some users are not expected to see all the content or be able to do what they want on our systems. That also hinders malware to abuse your system.

Yes, it does not make Linux invulnerable. But as long as it is easier to infect millions of Windows system than to infect 1 Linux machine we win. Only if your machine is targeted specifically (when you run a game server for instance) you need to take precautions. But those are: create regular backups, use a good password, use a router, keeping an eye on the CVE tracker, keeping your system up to date and not installing software you do not need. All things you should do any way.

Have you used other software showing better protection than ClamAV?

Yes (1st part: as a system admin for 30+ systems I have examined several virus scanners and root kit detectors and also made an assessment about threat risks when not using one) and no (2nd part). But the no is not because ClamAV is so good: it is as bad as any other virus scanner. Virus scanners all have such a low success rate that they are useless. When near 100% of all claims it claims to be a virus are false, I can't use it.

Are there any "enhancements" possible to increase the threat detection in ClamAV, since it is lightweight? (I have seen some websites suggesting to add their threat signatures to the ClamAV list. Is this safe?)

See for instance the "signatures.pdf" in the "doc" dir of ClamAV on how to upload extra virus signatures.

But this is only useful when you actually find a virus as the 1st person.  The virus definition file gets updates pretty regularly so I doubt there is anything to improve.

Overall (and this is important), below you can find additional tasks which can be performed for hardened protection, without slowing down the machine.

This is a question on its own and has also no relation to virus scanners.

Encrypt your system.
Do not install software that allows you to use FTP, Telnet, rlogin and rsh services
Minimize the software installed: don't use it? Remove it.
Keep your system up to date.
Use strong passwords and password aging.

Important:

The protection of your system does not come from anti-virus software; it comes from how you treat your system. If you ever do find a virus you are too late: removing a virus is not enough as your system has been compromized and needs to be re-installed from a proven clean backup. You always have to assume they got your admin password.


Install the driver from Canon (ver 3.90). Oddly, it shows up on its Asia site, but not on its US site. This worked for me on Ubuntu 14.04 Trusty.

http://support-asia.canon-asia.com/contents/ASIA/EN/0100517002.html

This driver was also linked by this Technosophy blog


Bash (and other shells) don't print PS1 as-is. They interpret it, and the display the output. Bash, for example, expands various special codes like \u, \w, etc., and then (from the Bash manual, Controlling the Prompt):

  After the string is decoded, it is expanded via parameter expansion,
  command substitution, arithmetic expansion, and quote removal, subject
  to the value of the promptvars shell option (see Bash Builtins).

Parameter expansion (i.e., variable expansion) means that a string like $PWD in PS1 is expanded. If you want to show a plain $PWD in the prompt, do either of:

PS1='\$PWD '
# or
shopt -u promptvars
PS1='$PWD '


Everything freezes except mouse. Ubuntu 12.10

The same happened to me when I was using KDE on Debian sid. So I stopped using it and switched to LXDE. It might happen due to shortage of CPU as in my case I was on a really old PC.


Give httrack (CLI) or webhttrack (web interface) a shot, it's in the universe repo. I'm not sure about the search-term-feature you describe, but it does offer a bunch of easily configurable options.

http://packages.ubuntu.com/de/oneiric/webhttrack

HTTrack Website Copier - Free Software Offline Browser (GNU GPL)


how to install anjuta 3.6 ide - 12.04 with kde

Normally, I would recommend you to add a PPA, but it seems there is no one available. This is my next step if a PPA is not to be found:

Just get the source of the Anjuta 3.4 debian package, change the sources to the version 3.6, and compile the package again.

From a console, get the debian package source.

mkdir ~/anjuta_compiling_place
cd ~/anjuta_compiling_place
apt-get source anjuta

Now, download the anjuta source code.

wget http://ftp.gnome.org/pub/GNOME/sources/anjuta/3.6/anjuta-3.6.1.tar.xz

If you are reading this after a while, instead of using this URL, get the latest version URL from http://www.anjuta.org/.

Rename (important for later steps!) and uncompress the downloaded source and cd into the directory:

mv anjuta-3.6.1.tar.xz anjuta_3.6.1.orig.tar.xz
tar xf anjuta-3.6.1.orig.tar.xz
cd anjuta-3.6.1

Uncompress the debian files:

tar xzf ../anjuta_*.debian.tar.gz

Install the required dependencies to compile anjuta:

sudo apt-get build-dep anjuta

Run debchange, and edit the first entry changing the first line with the correct version, for example:

anjuta (2:3.6.1-0ubuntu1) UNRELEASED; urgency=low

You could also add some text describing what you did, in the same fashion as all the other entries on that file. Be cautious!

Also, if you want to autosign the package, make sure your name and your e-mail are the correct ones. If you don't know what I'm talking about, just ignore it.

Now, save Ctrl+O and exit Ctrl+X.

And then compile the new package:

debuild

This could fail, but if you are lucky, after a while, you should have your new shiny debian package at ~/anjuta_compiling_place.

Now, just click on the packages on the correct order to install them, or issue these commands:

cd ~/anjuta_compiling_place
sudo dpkg -i libanjuta*.deb anjuta*.deb

If you find any difficulties, please add a comment and I'll try to make corrections and help you. Try to be as verbose as possible (copy & paste the errors, and so).


How to create 100 subdirectories using a Bash script?

The easiest way is probably to use brace expansion

mkdir subdirectory_{1..100}


N: Skipping acquire of configured file... as repository... doesn't support architecture 'foreign-architecture'

The reason it doesn't show amd64 is because that's not a foreign architecture, so when you ask for foreign architectures, it will naturally not be listed. dpkg --print-architecture will report amd64.

To remove the erroneous architecture, run:

sudo dpkg --remove-architecture foreign-architecture


Calendar constantly requiring Google authentication on 17.10

I was having the same problem and resolve it by deleting the configuration files of Evolution. Do this:

rm -rf ./.config/goa-1.0/accounts.conf
rm -rf ./.config/evolution
rm -rf ./.local/share/evolution

I don't have that problem anymore since I did that. I hope this could help you.


Software center not opening on Ubuntu 13.04 due to Gdk-ERROR

So it seems it is actually a known bug.

https://bugs.launchpad.net/ubuntu/+source/software-center/+bug/1163886

There is a hack which involves commenting out a line described in the bug report which basically is this:

self.exhibit_banner.set_exhibits([FeaturedExhibit()])

inside the file:

/usr/share/software-center/softwarecenter/ui/gtk3/views/lobbyview.py

ugly, but works.


I was just having this problem and fixed it by going to Settings -> Online Accounts and removing my Google account (it was the only one I had, so you might have to do it for others as well).


How to rollback the view style of file holder as 12.04 in 14.04

I've found the answer: in the upper-right, there are a small sun, click it, and in the Preference, and in the third tab, click on the view in tree view. Then the tree goes back.


How do I find a time stamp on a file and then echo it into the contents of the file as the first line?

Like so:

( stat -c %y test_file.txt | awk -F '.' '{print $1}' ; cat test_file.txt  ) > /tmp/temp_file && mv /tmp/temp_file test_file.txt

Here's a small demo:

$> echo "Hello World" > test_file.txt
$> ( stat -c %y test_file.txt | awk -F '.' '{print $1}' ; cat test_file.txt  ) > /tmp/temp_file &&
> mv /tmp/temp_file test_file.txt
$> cat test_file.txt
2016-08-03 09:24:27
Hello World

Explanation:

We get timestamp and file contents in subshell , signified by parenthesis (...)
stat -c %y test_file.txt | awk -F '.' '{print $1}' trimps timestamp
cat test_file.txt reads file contents.
The resulting text is timestamp plus whatever was in file, is being redirected to /tmp/temp_file
Finally we replace original file with contents of /tmp/temp_file


Dual Boot Windows and Ubuntu, Grub Problem

I will try to answer my own question. Apologies if my use of technical terminology is wrong. Aim: To get Ubuntu to boot as default, and allow me to boot Windows by playing with BIOS.

I believe the problem is the EFI on my machine does not allow me to boot from anything but /boot/efi/EFI/Microsoft/Boot/bootmgfw.efi, see here for a discussion of this. The following is a work-around for users who mainly use Ubuntu, but sometimes want to boot into Windows. My expectation is that this is mainly of relevance to HP-users, from accounts on the internet.

1) Install Windows, and then Ubuntu, see here

2) Restart the computer. If windows automatically boots then try using efibootmgr to give Ubuntu precedence, see here. If this works, you're done so stop reading.

3) If your computer is like mine, no matter what you do in efibootmgr, Windows will always force itself first. Changes you make will be undone when you restart the computer. In this case, the following hacks work for me.

4) Restart your computer, quickly press esc and go into the Boot Manager. There should be an option to start Ubuntu, choose that and launch Ubuntu.

5) Start a console and backup the important bootmgfw.efi to allow a boot to Windows

$ sudo -s
# cd /boot/efi/EFI/Microsoft/Boot
# cp bootmgfw.efi ./..

6) Create a new boot number, so we can boot up Windows in a hacky way by linking to the backup of bootmgfw.efi we just made. Run

# efibootmgr -c -L "Windows_2" -l "\EFI\Microsoft\bootmgfw.efi"
# efibootmgr -v

Use the last command to check the new entry was made. At this point I recommend you restart the PC and check booting into Windows_2 does indeed boot Windows. After you've done that, boot Ubuntu and cd back into /boot/efi/EFI/Microsoft/Boot

7) Renaming grubx64.efi to bootmgfw.efi allows us to boot Ubuntu first. Now enter the following commands:

# cp ../../ubuntu/grubx64.efi .
# cp bootmgfw.efi bootmgfw_backup.efi
# rm bootmgfw.efi
# cp grubx64.efi bootmgfw.efi

This should now work. Restart your machine.

Expected behaviour: Upon booting the PC, grub should open up as the default, allowing you to launch Ubuntu. Trying to launch Windows from grub will just link you back to grub in a never-ending loop. To launch windows, you must restart the computer, quickly press esc and go into the Boot Manager. Select Windows_2 and that will launch windows.

Hacky but it works so far. I will update the post if it turns out this ruins my computer.


i've finally found my fix for this.

It's a terminal user issue where i ran a command for log in with terminal.

I fixed it with this command: gnome-terminal -x /bin/bash

Then fixed the log-in command. That's how i fixed the issue.

Anyways, thanks for the help.


Change port for Desktop sharing in Ubuntu 12.10

The tool is dconf-editor. Install it by installing the dconf-tools package from the repositories. Open it, and navigate to desktop.gnome.remote-access.


old application launcher window in the repository

I can't find any applications specifically designed to do this with the layout that you describe, but Whisker Menu has this layout.

Whisker Menu is a plugin for Xfce that gives the user a nicer menu, and appears when it's clicked on the panel.

However, if you're desperate, you can run it inside Unity with some hacks - open up a terminal and do the following:

Install xfce4-panel: sudo apt-get install xfce4-panel
Install Whisker Menu: sudo apt-get install xfce4-whiskermenu-plugin
Run Xfce panel by pressing Alt F2 and typing xfce4-panel
Choose to create one empty panel if asked.
Right-click and go to panel preferences.
Resize it to the size you want and click 'items'.
Add Whisker Menu to the panel by clicking the 'Add' button and choosing it.
Close the preferences and done - now you have a panel with Whisker Menu!


Download Teamspeak. Open a terminal and run the following commands:

sudo cp TeamSpeak3-Client-linux_x86-3.0.12.run /opt
cd /opt
sudo chmod +x TeamSpeak3-Client-linux_x86-3.0.12.run
sudo TeamSpeak3-Client-linux_x86-3.0.12.run

The script creates a folder with the name TeamSpeak3-Client-linux_x86. Start the client with:

TeamSpeak3-Client-linux_x86/ts3client_runscript.sh

Create a desktop file:

nano ~/.local/share/applications/teamspeak.desktop

Add the following content:

[Desktop Entry]
Type=Application
Name=Teamspeak 3 Client
Comment=Teamspeak 3 Client
Icon=teamspeak3
Exec=/opt/TeamSpeak3-Client-linux_x86/ts3client_runscript.sh
Terminal=false
Categories=Games;
StartupWMClass=Teamspeak

The entry Icon=teamspeak3 you need to replace it with an icon of your choice. In my icon theme is an icon for Teamspeak 3.


How do I set up a private apt repository that can support multiple versions?

I needed a multi-versioned repo for the same reasons like you and this is what I ended up with:

apt-get install apache2 dpkg-dev
mkdir -p /var/www/repo/binary

Then create update-repo.sh that will update your repo with the packages' info

#!/bin/bash
cd /var/www/repo
dpkg-scanpackages -m binary /dev/null | gzip -9c > /var/www/repo/binary/Packages.gz

Place your .deb files in /var/www/repo/binary and run update-repo.sh

On the rest of the machines:

echo "deb http://myserver/repo binary" > /etc/apt/sources.list.d/myrepo.list
apt-get update

etc etc...

The magic happens because of -m when running dpkg-scanpackages. Without -m, only one version is listed in Packages.gz

I haven't tried it but it should be trivial to do the same for separate sub-repos, like hbdgaf proposed.


Change the default file manager applications use to open files (ubuntu 16.04)

Well Open terminal and install exo-utils

sudo apt-get install exo-utils

Now run the following command in terminal

exo-preferred-applications

Under Utilies Tab you will have File Manager to choose.

If you are using Xubuntu distros then go to
Settings Manager > Preferred Applications > Utilities , there you have the dropdown option to select the File Managers you already installed.

if above things fails then try running following command in a new terminal.

xdg-mime default Krusader.desktop inode/directory application/x-gnome-saved-search


Install crossbuild-essential-armhf on amd64

Ubuntu uses separate repos for armh (i.e. http://ports.ubuntu.com/).
To be able to install crossbuild-essential-armhf successfully you have to follow these steps:

run dpkg --add-architecture armhf

specify the correct architecture for ALL your apt deb lines in /etc/apt/sources.list and /etc/apt/sources.list.d, for example:
deb [arch=amd64,i386] http://archive.ubuntu.com/ubuntu trusty main universe
deb [arch=armhf] http://ports.ubuntu.com/ trusty main universe

Note that it does not make sense to specify the arch for deb-src lines.
3. run apt-get update
4. run apt-get install crossbuild-essential-armhf
Have a look at https://wiki.debian.org/Multiarch/HOWTO
You may also want to execute these commands in a chroot (or docker container maybe) as mentioned by this guide: Getting Started with MultiArch (armel / armhf) in Ubuntu


I want to remove windows partition using gparted

Not much ... backup ALL IMPORTANT data, make sure that you are deleting the right partition. Proceed with deletion of the Windows partition - afterwards update GRUB : sudo update-grub

Refer here for more details : https://help.ubuntu.com/community/HowToRemoveWindows


Looks like a bug, but you can try to play with this Settings:

You can report a bug here https://bugzilla.xfce.org/buglist.cgi?component=Decorations&product=Xfwm4&resolution=---


gomaasapi maintenance/support or is it a dead project?

This is a repo that is worked on by various Canonical teams, mostly the Juju and MAAS teams. You're right that it's not Ubuntu software in the Ubuntu archives, but pinging in IRC or discourse sites like discourse.maas.io or discourse.jujucharms.com is completely appropriate. Thanks for hacking on the code there. I'm sure we look forward to helping get your contribution into the codebase.


Sounds to me like the problem is with the video output. It must be going through Intel onboard graphics by default instead of your gpu. If your monitor is plugged into the gpu try plugging into the onboard graphics instead. It's located directly on the motherboard I/O. I hope that helps.


Unable to build python 3.7.0 "_dbm" optional module

I was able to satisfy the dbm requirement via this module

sudo apt install libgdbm-compat-dev

It looks like the older "dbm" files are moved to "gbdm-compat" package.


The CDK bundle does not add kubernetes-worker nodes on high workloads. AFAIK Conjure-up also does not provide this. Juju allows you to scale the number of master / worker nodes manually via juju add-unit.

If you really want autoscaling feature you can look at non canonical solutions such as the following bundle.

Pod scaling works on the Kubernetes level and does not require node auto scaling.


Terminal immediately closes itself after opening

For some reason, the key mentioned in the error message now contains a '&'. To see what its value currently is, open a console terminal, as this won't suffer from this bug: press CTRL + ALT + F1 (or F2...F6), login, and do:

gsettings get org.gnome.desktop.interface monospace-font-name

To change it, do

gsettings set org.gnome.desktop.interface monospace-font-name 'Ubuntu Mono 13'

(or any other value you like).

You can also run Software Center or Synapsis and install dconf-editor. This gives you a GUI that will let you view and change the value of the key.


adding exif data (photo taken date) to photos

You can edit the properties, on a PC r-click and edit the properties. On a Mac the steps are similar.

You are aware you can't really get accurate data from original photo but can add exif data.

There are software programs that can actually do batch jobs. I believe the best way would be to sort files, put them in labelled folders: Mom, POP, Billy-Bob and use the batch function that way.

Afterwards you could make minor exif adjustments if needed and save yourself some pain-staking work.


interpreting Sensors command line output

The output of sensors is usually pretty raw and it really depends on the Kernel support for your particular I²C bus, and how the monitors are attached to the system.

Having said that, the coretemp-isa-0000 ones are obviously your CPU.

The rest are a bit more of a guess. I would suggest that the first couple could be additional under-CPU thermometers and the others could be various chipset monitors around the motherboard.

It's hard to be exact because it's layered behind ACPI rather than being exposed as a normal I²C device.


Why one Thunar folder doesn't show icons as in the other one?

The folder /usr/share/applications is handled in a special way and the icons displayed for a .desktop-file are defined in the .desktop-file itself. If you take a deeper look you will see that Thunar also does not display the real file names in /usr/share/applications but an alias which is also defined in the .desktop-file.

For the folder ~/local/share/applications all this is not the case, Thunar displays the real file names and the default icons for the different file types.

The question Can Nautilus display a .desktop file by its real name? is heavily related, at least regarding the displayed file names.

Trick with soft-link:

If you want to display the files in ~/.local/share/applications in the same way as files are displayed in /usr/share/applications, you could do it with a soft-link placed in /usr/share which points to ~/.local/share/applications:

sudo ln -s ~/.local/share/applications /usr/share/applicationsinhome

Now you can browse in Thunar to /usr/share/applicationsinhome. This will display the files located in ~/.local/share/applications in the same way as the files in /usr/share/applications and you would still be able to delete, create or edit files without root-privileges.

Please take a look at my answer in the linked question too, there I explained how to do it the other way around.


If you have a bootable Ubuntu CD, than boot from the CD, after chroot your failed system:

sudo mount /dev/sda1 /mnt

sudo mount --bind /dev /mnt/dev
sudo mount --bind /proc /mnt/proc
sudo mount --bind /sys /mnt/sys

sudo chroot /mnt

After that issue again the sudo apt-get update && sudo apt-get upgrade commands. If it fails, than run sudo dpkg-reconfigure -a. If finishes, reboot, remove the CD, and try to boot normally. I hope that it helps.


I had the same problem, wireless network would ask for a password to authenticate, then connect and after a couple of seconds it would disconnect again. This process would repeat itself over and over. Even with entering the password directly at the wireless security tab as described here, it would still pop-up with the password dialog box & sometimes connect, but still keep on disconnecting.

This is what I did to solve the problem - it's a workaround, but hopefully later updates will fix this issue.

Establish a connection to your wireless connection
Click on the network icon at the top right-hand of your screen
Select 'Edit Connections' at the bottom
Select the 'Wireless' tab
Select your network & hit 'Edit'
Select the 'IPv6 Settings' tab
Where it says 'Method: Automatic' make it 'Ignore'

That "solved" the problem for me, of course it potentially creates other issues if you need IPv6 on your wireless connection, and hopefully that gets resolved later with updates from Ubuntu or upstream.


Use Wubi, or, on the installer, select to install alongside Windows 7.


How to get the old alt + number key behavior in gnome-terminal?

You can remove these shortcuts in Edit > Preferences, in which case these will always be forwarded to the terminal program.

The "dual" behavior (the action being based on whether there are at least as many tabs as the number you pressed) is no longer available.


When the dialog appears, select Manual partitioning, then if there is free space in your Hard Disk, install Ubuntu there, otherwise choose to resize the windows partition (make sure you have at least 10 GB of free space for Ubuntu). As BeGood commented above, it is better to try a LTS release or install the latest release.

Check this for more info.


Only I can initiate ubuntu 12.04 in my notebook, only if I place the memory USB with which I installed it

Sounds like grub installed on the USB drive.
Try booting with the USB drive installed,
Safely remove the USB drive.
In terminal run:

update-grub


How can I get rid of old Debian entries in my bootloader?

According to the information acquired in the comments, you only want to remove the Debian entry from the UEFI boot menu. To do that:
Open a terminal and run:
sudo efibootmgr

The output will be, as stated in the question, like this:
BootCurrent: 0001
Timeout: 1 seconds
BootOrder: 0001,0004,0002,0003
Boot0001* ubuntu
Boot0002* UEFI: PXE IPv4 Intel(R) Ethernet Connection (10) I219-V
Boot0003* UEFI: PXE IPv6 Intel(R) Ethernet Connection (10) I219-V
Boot0004* debian

To remove the unwanted entry (debian in this case), run:
sudo efibootmgr -b 4 -B

which will delete the following entry: Boot0004* debian.
After that, remove the debian folder from the EFI partition by running:
sudo rm -r /boot/efi/EFI/debian

Since grub doesn't seem to have references to debian, the process stops here.
At the reboot you shouldn't see debian anymore.
Thanks to this answer and mook765.


Tizen has their own installers to do already what are you trying to do https://developer.tizen.org/sdk

And this installer has two options: one where it downloads the file from the Internet and the other (as an Advanced buton in the initial stages of the installation)were you can manually specify a very big zip like probably for example TIZEN-IDE_1.0.0_windows.zip

What you have might be an internal version of the installer from Samsung, since Tizen is a opensource project you better try to install it from the above mentioned link, not to mention that if there is a release it will certainly appear online.


Mounting a drive as a directory: Am I doing it right?

According to the FHS, /mnt is used for manual mounts. While you can mount it anywhere, if you want to follow convention, you would mount the drive to a folder in /media. This is where Ubuntu by default will place secondary drives at install time.

You however, according to this answer anything mounted from /mnt will not appear there so you may be inclined to break this convention.

Drives that are listed in /etc/fstab will also reside in /media.
As for your mounting options, the defaults are okay.

Potential Answer


I suggest to have a look at KDE's Task Scheduler (kde-config-cron)  which allows to set up crontabs.

This is a Qt application which does already do what you're trying to achieve. It's GPL licensed code.


Please note that symbol:

  '

Single quote

   Enclosing characters in single quotes preserves the  literal  value  of
   each character within the quotes.  A single quote may not occur between
   single quotes, even when preceded by a backslash.

and

  `

Backquote

   Command substitution allows the output of a command to replace the com‐
   mand name.  There are two forms:

          $(command)
   or
          `command`

   Bash performs the expansion by executing command and replacing the com‐
   mand  substitution  with  the  standard output of the command, with any
   trailing newlines deleted.

So the Backquote is returning result of the command to Standard Output. That is why

`wc -l sample.txt`

returns results of the command, while

  'wc -l sample.txt'

just return "wc -l sample.txt" as usual string

Consider doing this as example:

$ A='wc -l /proc/mounts'
$ B=`wc -l /proc/mounts`
$ C=$(wc -l /proc/mounts)

And now echo all three variables:

$ echo $A
wc -l /proc/mounts
$ echo $B
35 /proc/mounts
$ echo $C
35 /proc/mounts


Is there a grid shell extension for gnome? like compizconfig

Found it in Ubuntu Software. "Put Windows" GNOME shell extension. sweet.


You can use Krfb Desktop Sharing, this is a server application that allows you to share your current session with a user on another machine, who can use a VNC client to view or even control the desktop.

Install it using the following command:

sudo apt-get install krfb

Here is a link to more info about it: Krfb Desktop Sharing

Another option is to use xrdp and set this to use KDE.

You can install it by executing:

sudo apt-get install xrdp

Then, execute this command to configure xrdp to use KDE desktop environment>

echo startkde >~/.xsession

After that, restart the xrdp service with:

sudo service xrdp restart

NOTE: This config will only allow one user to connect to XRDP and use the KDE desktop environment. This would be the user for which you have updated the xsession file.

Hope it helps.


Difference between 49-haproxy.conf and haproxy.conf files

From a blog post:

  Thanks for this! It saved me a lot of time.

  One thing I'd suggest changing -- in Ubuntu Oneiric (and I suspect in
  older versions), the rsyslogd config you specify will leave haproxy
  logging in both /var/log/haproxy_1.log and in /var/log/syslog. This is
  because rsyslogd writes each message out using every rule in its
  configuration that matches unless specifically told not to.

  The "& ~" at the end of your file /etc/rsyslog.d/haproxy.conf means
  "once you've written something using the rule above, don't process any
  more rules for this message". But it won't stop messages from being
  written out by rules that were specified before the one in
  /etc/rsyslog.d/haproxy.conf

  Now, the default Oneiric config has a file called
  /etc/rsyslog.d/50-default.conf which does the default configuration,
  including a catch-all "write everything to syslog" rule. And because
  files from /etc/rsyslog.d/ are included in alphabetical order, the
  rules in 50-default.conf are applied before the ones in haproxy.conf
  -- so you get your haproxy stuff dumped into both files.

  The solution is obviously to call your own rsyslogd config file
  something like /etc/rsyslog.d/49-haproxy.conf


How can I completely uninstall mysql-server and reinstall?

To remove all config files use

apt-get purge mysql-server\*
rm -rf /etc/my.cnf /etc/mysql

If you want to delete all databases as well, you need to delete the directory /var/lib/mysql, too.


Shutdown, Restart and Logoff buttons not working in Ubuntu 13.10

I had this problem as well, try this:

Edit /usr/lib/cairo-dock/cairo-dock-launcher-API-daemon as root (if a blank/new document is created: cancel it and edit /usr/lib/i386-linux-gnu/cairo-dock/cairo-dock-launcher-API-daemon as root)

Add the following at line 33 (After anything in that line):

from time import sleep

And add the following at line 241 (just right before ULWatcher()):

sleep(5)

Then restart the session or the computer.
Hope that helps, good luck and have fun.


If only the folders you use in ubuntu, I recommend ext4 partition with the partition that you can use at any time as an external drive.


Does anyone know why does Ubuntu 11.10 use TeXLive 2009?

As far as I understand, the main reason is that no one did the work to package TeXLive 2010 and 2011 for Debian/Ubuntu.

See Ubuntu Bug #712521: [Needs packaging] TeXLive 2011 (especially the comments) for some background information.

The current advice (from the TeX community) is to install TeXLive 2011 yourself, either instead or additionally to the TeXLive 2009 from Ubuntu.


Can Snaps or Flatpacks be installed from a local file?

Snaps and Flatpacks (and Debs and AppImages) can all be installed locally.
Choosing among them depends on more than current skills. Consider also the security patches you will need to promulgate, the support you will need to provide, and the future upgrades you intend to release.


Failed to unmount /oldroot/dev warning during the shutdown or restart

Seems to be related to update from 18.04, for some reason it left some old legacty Kernels untouched. Reinstalling system (because of another issue) solved the problem.


/var/lock (and others such as /var/run and /dev/shm) are filesystems that are actually stored in system RAM. There's no need to "recover" the space, and it's rather ineffective to use it for yourself. It's used so that system locks and other tasks can run and be used efficiently.

Don't worry about how much space it claims is available, just look at the Used column for information on how it's actually being used. In your case, none of /var/lock is being used at all, but there's a little bit used for /dev/shm and /var/run. Nothing to worry about, just the system operating normally.


Update to 11.10 without touching the kernel?

You can still upgrade to 11.10 or whatever one u want and install an old kernel image.
Old images can be found here. Just look for the version you are using then install it.

Note, you should download a total of 3 packages in each case.
Then from terminal run:

sudo dpkg -i *.deb


Authentication failure won't resolve in Ubuntu One

Take a look at => Ubuntu One - Sync error

For me, all I had to do was:

sudo rm -rf ~/.local/share/ubuntuone

Some folks have suggested this was not enough to correct their problem.  For them I suggested that they work though the entire sequence of commands.  Hope this helps.


I can't find my Wi-Fi settings in Ubuntu 20.04

You have to connect your PC through wired connection/ethernet cable then through Software Updater you update Ubuntu. When it is done restart your machine and it should be working fine.


Creating a script for duplicating a server setup

Trinity Rescue Kit has a cloning feature.

Would that be of any use?
It can clone entire harddisk which would include your OS and all files.

[1] http://trinityhome.org/manpages/man8/mclone.8.html


What to do about errors with update & upgrade?

Basically, this means that in your /etc/apt/sources.list, you have the same repository listed twice.

This isn't exactly an error, it's a warning, and it is pretty harmless one too.

However, if you wish to stop these warnings appearing, read below, understand, then decide what you feel is best. If you don't feel comfortable with either, then don't do this. The messages you get are a warning, and isn't even remotely harmful to your OS.

First things first: Back up your /etc/apt/sources.list file in case you make a mistake. Open up a terminal, and run:

sudo cp /etc/apt/sources.list /etc/apt/sources.list.backup_warning

(I tend to add descriptive titles to my backups instead of numbering them in case I need to go back to them later)

Now you have two ways to fix this

The simple way: Open up the Ubuntu Software Centre. On the Menu bar, click on Edit and go all the way down to Software Sources.

Click on the Other Sources tab and maximise the window to prevent removing the wrong repository. Go through the list until you find the repositories listed above and then untick. Then press close and allow the Ubuntu Software Centre to refresh packages.

If you have done this right, you should have no more warnings.

The mildly complicated way: Open up the terminal. Type

sudo gedit /etc/apt/sources.list

and then find those URLS listed above and place a hash ('#') symbol before the lines. Again, if you have done this right, you should have no more warnings.

Personally, I'd recommend you go down the simple way, as there is less chance of shooting yourself in the foot and damaging your repository updating mechanism. Or failing that, don't make a single change. Your system is absolutely fine the way it is.


gnome-open raises this error when run from inside tmux

Instead of letting Gnome run dbus-launch to create a random D-Bus address, start dbus-daemon explicitly early in your X session startup and give it a fixed address like unix:path=~/.dbus-$HOSTNAME-$DISPLAY.

Given the information in the bug report, you may even be able to get away with unset DBUS_SESSION_BUS_ADDRESS and let applications find out the bus address from the root window properties.

As of 15.10, the per-session dbus instance is created via an Upstart session job. The job file in question is /usr/share/upstart/sessions/dbus.conf. You can replace the default random address by overriding the pre-start script stanza which specifies the address to use. Create ~/.config/upstart/dbus.override with the following:

pre-start script
    DBUS_SESSION_BUS_ADDRESS=unix:path=$HOME/.dbus-$(hostname)-$(echo $DISPLAY | sed -e s/:/%3A/)
    initctl set-env DBUS_SESSION_BUS_ADDRESS=$DBUS_SESSION_BUS_ADDRESS
end script

The fixed address will be used after you next log in.


403 Forbidden and "The repository 'http://security.ubuntu.com/ubuntu bionic-security InRelease' is no longer signed" errors on Ubuntu 18.04

This is not necessarily a temporary issue. It's an ongoing one. There could be many causes for this issue, and the one that I keep seeing is this. Canonical, like a lot of other companies uses Akamai, which has servers located around the world and appear to use a round-robin approach concerning which servers get used at any particular time. This can cause an issue, like the 403 Forbidden the OP saw, if the servers in use by Akamai happen to be in a location which your firewall is blocking via IP geolocation. Right or wrong, there are a lot of organizations which do geolocation blocking and as a result these errors will occur.
To see if this is indeed the case in you particular instance, type the offending IP into your browser's address bar, hit return and see what happens. If you get a message from your firewall stating that that location has been blocked, then you will need to wait and/or keep trying until the servers being accessed are in a location which your firewall is not blocking.
The 403 Forbidden error occurs because apt cannot retrieve the signature file for the repository, since the IP is being blocked. It would be nice if apt could better deal with this issue, but it is what it is and we just need to troubleshoot.


The command to display soundcards is aplay -l not aplay -i
As there is sound at startup , try to disable speech-dispatcher running
sudo update-rc.d -f speech-dispatcher remove
and reboot
If no luck, disable pulseaudio for testing, so you can check if underlaying alsa driver works fine. Run 3 commands::
mkdir ~/.pulse
echo autospawn=no > ~/.pulse/client.conf
pulseaudio -k
Now any audio softwares will use only alsa: test sound (check volumes and mute  using alsamixer or install  "alsamixergui ").
If it is ok, pulseaudio is broken : reset it with
mv ~/.config/pulse ~/.config/pulseold
echo autospawn=yes > ~/.pulse/client.conf
pulseaudio
This will launch pulseaudio with new configuration ,test again.


How to output a file from line x to another

You could do something like tail -n +5 projects.txt >> newProjects.txt. The -n +5 will "skip" the first 4 lines of projects.txt.


You can find this option under System > Administration > Login Screen.

You'll need to "unlock" the window as this requires administrative privileges.

You can then select the user and session you would like logged in automatically.


The installation of emacs is possible with the following commands:

sudo su
mount -o remount,rw /
apt-get install emacs

You need a passphrase or a number code for your phone and you need to install the com.ubuntu.terminal-app to input these commands.
Emacs is also started from com.ubuntu.terminal.

Specification of my phone: BQ Aquaris E5 Ubuntu-Edition

# uname -a
Linux ubuntu-phablet 3.4.67 #1 SMP PREEMPT Fri May 29 10:43:18 UTC 2015 8e13c5f armv7l armv7l armv7l GNU/Linux

Attention: As far as I understand what I read before, updating the phone via GUI is no longer possible after that.

Currently, I am asking here whether updating via apt-get is a full replacement.

I am using the following configuration file ~/.config/com.ubuntu.terminal/Layouts/emacs.json for working with emacs using the built-in virtual keyboard.
This configuration is far from ideal. I posted it here, since it is difficult to start without any emacs-adapted soft-keyboard on the console.

{
    "name" : "GNU emacs",
    "short_name" : "Emacs",

    "buttons": [
         {
            "main_action" : {
                "type": "key",
                "text" : "E",
                "key" : "Escape"
            }
        },
         {
            "main_action" : {
                "type": "key",
                "text" : "T",
                "key" : "Tab"
            }
        },
       {
            "main_action" : {
                "type": "key",
                "text" : "Cg",
                "key" : "G",
                "mod" : "Control"
            }
        },
        {
            "main_action" : {
                "type": "key",
                "text" : "Cx",
                "key" : "X",
                "mod" : "Control"
            }
        },
         {
            "main_action" : {
                "type": "key",
                "text" : "Cc",
                "key" : "C",
                "mod" : "Control"
            }
        },
       {
            "main_action" : {
                "type": "key",
                "text" : "C_",
                "key" : " ",
                "mod" : "Control"
            }
        },
        {
            "main_action" : {
                "type": "key",
                "text" : "Cf",
                "key" : "F",
                "mod" : "Control"
            }
        },
        {
            "main_action" : {
                "type": "key",
                "text" : "Cs",
                "key" : "S",
                "mod" : "Control"
            }
        },
        {
            "main_action" : {
                "type": "key",
                "text" : "Mx",
                "key" : "X",
                "mod" : "Alt"
            }

        },
        {
            "main_action" : {
                "type": "key",
                "text" : "Cw",
                "key" : "W",
                "mod" : "Control"
            }
        },
        {
            "main_action" : {
                "type": "key",
                "text" : "Cy",
                "key" : "Y",
                "mod" : "Control"
            }
        },
        {
            "main_action" : {
                "type": "key",
                "text" : "Mw",
                "key" : "W",
                "mod" : "Alt"
            }
        },
        {
            "main_action" : {
                "type": "key",
                "text" : "Cv",
                "key" : "V",
                "mod" : "Control"
            }
        },
        {
            "main_action" : {
                "type": "key",
                "text" : "Cu",
                "key" : "U",
                "mod" : "Control"
            }
        },
        {
            "main_action" : {
                "type": "key",
                "text" : "Cw",
                "key" : "W",
                "mod" : "Control"
            }
        }
    ]
}


cp -r not copying all files from networked drive

Most probably the reason is that the source directory contains symbolic links.

From https://www.gnu.org/software/coreutils/manual/html_node/cp-invocation.html#cp-invocation:

  When copying from a symbolic link, cp normally follows the link only when not copying recursively or when --link (-l) is used. This default can be overridden with the --archive (-a), -d, --dereference (-L), --no-dereference (-P), and -H options. If more than one of these options is specified, the last one silently overrides the others.

Add the -L-option to your cp- command:

cp -rL /media/drive/dir /home/USER/Desktop/dest


Problem Installing Network Simulator 2 in Ubuntu 18.04

Ubuntu 18.04, simply do : sudo apt install g++-4.8  https://packages.ubuntu.com/search?suite=default&section=all&arch=any&keywords=g%2B%2B-4.8&searchon=names ... Please note that you can have as many gcc versions as you want, installed at the same time. Other examples https://drive.google.com/drive/folders/1xVEATaYAwqvseBzYxKDzJoZ4-Hc_XOJm?usp=sharing
Build ns-2.35 :
tar xvf ns-allinone-2.35_gcc5.tar.gz    (2014 update)

https://drive.google.com/file/d/0B7S255p3kFXNVVlxR0ZNRGVORjQ/view?usp=sharing
cd ns-allinone-2.35/
export CC=gcc-4.8 CXX=g++-4.8 && ./install
cd ns-2.35/
sudo make install


java home will not set using /etc/environment

/etc/environment is not read by the shell but by the pam_env PAM module.

So it is only evaluated at login time and you can't use shell syntax but only

VARIABLE=VALUE

lines.

Use

echo 'JAVA_HOME=/usr/' | sudo tee -a /etc/environment

and login again.


Please try this:

sudo update-manager -d


custom system.d service fails at startup

You need to enable the service in order for it to run at startup. Please run:

sudo systemctl enable alwayson.service

Then it should work automatically after reboot.


Can I feed a bash script a local file into $1 and have it echo the file's absolute path?

Script is not necessary. A single readlink command is sufficient:

$ cd /etc/

$ readlink -e passwd
/etc/passwd

From the man readlink:

   -e, --canonicalize-existing
          canonicalize by following every symlink in every component
          of the given name recursively, all components must exist


I think you could type the sudo password slowly, and be attentive on what you are typing. This could help. Or change the password if you still can't.


How to monitor what Ubuntu One is doing?

Install Magicicada. It will allow you to see what Ubuntu One is doing with a nice interface.

sudo apt-get install magicicada


Can't report a bug on for a project on Launchpad--What to do (e.g. Skype Wrapper)

Those using Launchpad can use it for many things, or can choose only to use certain features. It appears to me that the group providing a PPA for Skype Wrapper only use Launchpad for hosting the packages in a PPA. Some projects may include a pointer to a bug tracker or to the project's homepage, but I don't see one in this case.

There is no rule that a project with a package in a PPA must take bug reports or continue to maintain their package.

Ubuntu uses the infrastructure developed by Debian, and packages follow Debian's rules. Included is a rule that all packages must include a changelog and that they should contain the e-mail for the person responsible for the change.

Assuming you have installed the package you can view /usr/share/doc/skype-wrapper/changelog and view the last (top) changelog entry and that entry will give you a possible e-mail address you could use to ask that individual if bug reports are taken and where to send them. For the skype-wrapper package there is only one entry at this time.


Fingerprint issue in lenovo thinkbook14 iml

This solution worked for me. I'm using a thinkpad x1 carbon gen 6
$ sudo apt remove fprintd
$ sudo add-apt-repository ppa:uunicorn/open-fprintd
$ sudo apt-get update
$ sudo apt install open-fprintd fprintd-clients python3-validity
...wait a bit...
$ fprintd-enroll

If fprintd-enroll returns with list_devices failed:, you can check the logs of the python3-validity daemon using $ sudo systemctl status python3-validity. If it's not running, you can enable and/or start it by substituting status with enable or start.
It systemctl status python3-validity complains about errors on startup, you may need to factory-reset the fingerprint chip. Do that like so:
$ sudo systemctl stop python3-validity
$ sudo validity-sensors-firmware
$ sudo python3 /usr/share/python-validity/playground/factory-reset.py

# At some of the above points you may get a 'device busy' error,
# depending on how systemctl plays along. Kill offending processes if
# necessary, or re-run the systemctl stop python3-validity command,
# in case it has automatically been restarted, or or kill other
# offending processes.

$ sudo systemctl start python3-validity
$ fprintd-enroll

I got the solution from https://github.com/uunicorn/python-validity


Packard Bell VAB70 keyboard & touchpad not working

6 years and two months later, I stumbled upon the same problem (beside a few functions keys, the keyboard and touchpad are unusable under Linux Mint/Ubuntu 20).
For the posterity, I found that upgrading the BIOS to it's latest version (1.10, released on 2011-12-19) solved the issue!
Notes
I downloaded the driver from the download center, in the support section, at https://www.packardbell.com/.
On this site, VAB70 yield zero results; if you do not want to search by Serial Number or SNID, the product can be found under the reference EasyNote LK11BZ.
The archive is named BIOS_PackardBell_1.10_A_A.zip.
The SHABV110.exe will flash from a running Microsoft Windows.
I did not try the Update.bat from a FreeDOS or similar environment.
Checksums
MD5
5ccada9d9dec8443466ba6745d0ed943  ./BIOS_PackardBell_1.10_A_A.zip
ef58f5d68616190d882621d98732459a  ./BIOS_Packard Bell_1.10_Windows/DOS/flashit.exe
b65333b6c8810c4e068e0c59483d745d  ./BIOS_Packard Bell_1.10_Windows/DOS/Update.bat
7b4ac9dc2928931ead357bd6c9e9e5d6  ./BIOS_Packard Bell_1.10_Windows/DOS/SHABV110.FD
025e2c6f894b95ec544c26f014ad5b3c  ./BIOS_Packard Bell_1.10_Windows/Windows/SHABV110.exe
117059c0347ae37ef1bcc2e54b378c6c  ./BIOS_Packard Bell_1.10_Windows/readme.txt

SHA256:
c6bb3f5a43a19e1b1e9fd71522b0cc2c679d5f82abc82bfe46a7ecdbe2df1335  ./BIOS_PackardBell_1.10_A_A.zip
97b43dc375d65a3eecb6f7e2dc24f7b10fd20e1c3dba4e1c62ea6a33a344b1b9  ./BIOS_Packard Bell_1.10_Windows/DOS/flashit.exe
2c97ae51c297f2c18e5dcbf30576615876d0c132fef0d41883cecb9f8162575f  ./BIOS_Packard Bell_1.10_Windows/DOS/Update.bat
97f4d89f503058c61e80e297ae805580c1f278eb46aa38e4c10aeeb219147d5f  ./BIOS_Packard Bell_1.10_Windows/DOS/SHABV110.FD
7aa337d3177798a7e576eb89031ceedb4c0addc51b579027ada804667ac29e6b  ./BIOS_Packard Bell_1.10_Windows/Windows/SHABV110.exe
45a250af68fd6592f3d578578717114c2ecedf0d02efc7bf50b7c04ab60e54a4  ./BIOS_Packard Bell_1.10_Windows/readme.txt


What is the command to kill/close notifications?

You can use notify-osd itself. However, notifyosdconfig need to be installed separately. Use the ppa nilarimogard/webupd8 and install notifyosdconfig.