ModuleNotFoundError: No module named 'pandas' occurs even if pandas is installed on my machine

You have to remove locally installed python3 by
sudo apt-get install --reinstall python3-minimal
sudo rm /usr/local/bin/python3

and then install python bindings for Pandas with:
sudo apt-get install python-pandas python3-pandas


How to diff two folders to multiple patch files

You can use the original format that creates the huge diff file which you can subsequently split into the small files. You might be interested in csplit for the splitting, or you can use a scripting language like Perl:

perl -ne 'if(/^diff -drupN (.*) (.*)/) {
              my $f = $1;
              $f =~ s{/}{_}g;
              open $FH, ">", "$f.patch" or die $!;
          } else {
              print {$FH} $_;
          }' kernel.patch

If you need the diff line in each file, add the print after the open.


I have corrupted my sources.list Ubuntu 14.04

1.sudo nano /etc/apt/sources.list

2.Put a # at the beginning of the cdrom line you edited/added.

3.Ctrl+o to save, Ctrl+x to exit nano.

4.sudo apt-get update

If that works and you get no errors, you can try

5.sudo apt-cdrom add to get the cdrom entry added properly.


Why is zero swap being used on my setup?

Swap is kind of a "safety net" in case you run out of RAM, so the fact that it's not used until actually needed is entirely normal.

You're not using any swap because all the processes fit in your RAM. You won't actually see swap being used util processes actually need more space. Try opening a lot of tabs on your browser, or install the stress tool which you can use to stress your system's memory, and you will see swap being used.


why this shell script program is not working

That's because you are doing:

if [ expr $n % 2 -eq 0 ]

How come?

Because

rem='expr $n % 2'

is assigning variable rem as string expr $n % 2.

You need, command substitution:

rem=$(expr $n % 2)

Also use bash's native arithmetic operator instead of expr:

rem=$(( $n % 2 ))


Ubuntu desktop isn`t focussing after minimising a window on Ubuntu 16.04

The problem was with Telegram from atareo ppa. When i try to launch Telegram in a tray via /opt/telegram/Telegram -startintray then this strange behavior appears. If I quit Telegram (or start it as usual) everithing is back to normal. Don`t now exactly why Telegram produces this bug though. But it's aceptable workaround for me, thanks all!


How to reset all gnome-tweak-tool settings to defaults

Actually, you can simply open GNOME-tweak-tool (in GNOME), and click on its icon in the top panel. You should see an option that says "Reset to Defaults."


I am looking for a small (Ubuntu) open-source-project for which I can code

I good place to start is the One Hundred Paper Cuts project.


What is the currently accepted means of getting Nvidia to work on ubuntu 15.04?

I have just bought a new laptop with a nVidia 960m inside and it is a new hybrid model that also has an Intel graphics processor working side by side.

I do not know if that is the case for you but I asked a similar question here.

Installing nVidia driver on hybrid card

and the answer I got was to enter the Terminal and enter

sudo add-apt-repository ppa:xorg-edgers/ppa
sudo apt-get update
sudo apt-get install nvidia-352 nvidia-prime
sudo add-apt-repository -r ppa:xorg-edgers/ppa

This installs the latest driver 352.

Restart and you should be able to have the nVidia X Server Settings in the search bar with all the options etc.


Is it possible to install the .snap application in an offline computer?

It seems you first have to download and install the ubuntu-core snap before you can do offline installs for any other snaps. For me this worked:

Run the following commands on an online Ubuntu system:

snap download ubuntu-core
snap download somePackage

This will put the following files in your current directory:

ubuntu-core_1797.assert
ubuntu-core_1797.snap
somePackage.assert
somePackage.snap

Copy these files to the offline system, then install them (from the directory they were copied to):

sudo snap ack ubuntu-core_1797.assert
sudo snap install ubuntu-core_1797.snap
sudo snap ack somePackage.assert
sudo snap install somePackage.snap

This should solve the problem @lane had where it tried to connect to the internet while installing a local .snap file.


I had this problem was well, as I didn't need quantal images I just edited the /etc/maas/import_pxe_files. I changed the releases line to

RELEASES="precise"

I ran the command again and it worked


Empathy does not allow WLM accounts after upgrade to ubuntu 12.04

I just had this too. I found this helped:

sudo aptitude install telepathy-haze

Then open the Chat client, and Ctrl-Q to quit it completely, then run it again and try to add the account again, and it works (or it picked up my old accounts anyway).


Ubuntu Server 16.04.02 with Splash Screen and Kiosk mode

The boot messages are avoided by GRUB_CMDLINE_LINUX_DEFAULT="quiet splash". I don't know why you still get the cursor though.

Anyway, to answer your question about the plymouth, you want to install it by running the command sudo apt-get install plymouth. This should install it to the system. Then, your want to copy all of the contents of /usr/share/plymouth/themes/ubuntu-logo to another folder (Preferably somewhere in the /usr/share/plymouth/themes directory). Then, your most likely want to change the image ubuntu-logo in your newly copied folder. Then, to make the change to the new boot logo, edit the configuration file for plymouth located at /etc/alternatives/default.plymouth. There, change the address for the two lines below to the new folder you created earlier:

ImageDir=/usr/share/plymouth/themes/ubuntu-logo
ScriptFile=/usr/share/plymouth/themes/ubuntu-logo/ubuntu-logo.script

So, for example, I might edit the lines to be like this:

ImageDir=/usr/share/plymouth/themes/mytheme
ScriptFile=/usr/share/plymouth/themes/mytheme/ubuntu-logo.script

Then, save the configuration and reboot. You now should have your boot logo image instead of the regular Ubuntu one.


How can I set up multiseat with only one physical graphics card?

So this is an old guide, but it may still work. MultiSeatOneCard.
Some notes before I start bringing instructions over:

All the gdm configuration it wants you to do may not even be necessary. If you have GNOME, you already have gdm (and a much newer version). Unity uses lightdm, which looks like it may not work. You should install gdm and use it to try this guide.

Just another warning: OLD GUIDE. It may not work, it may break Ubuntu, it may blow up your machine (not really of course). Please be careful and back stuff up.

Now for the guide
The wiki suggests disabling the splash screen with the following. I don't know if the procedure still works or not.

A lot can go wrong with this setup and the fancy splash screen during the boot doesn't help. In order to disable it (maybe temporarily) edit /etc/default/grub and change the GRUB_CMDLINE_LINUX_DEFAULT assignment from quiet splash to nomodeset noplymouth. Then run sudo update-grub.

The next part, about "expanded desktop" can probably be skipped too. Just plug in both monitors and set them to "extended mode" in your monitor settings.
Now, for some configuration.

First, find in /etc/gdm/gdm.conf, in the [servers] section a line starting with 0=.... (without # at the beginning of the line). Put a # in front of it.

That should be possible without much trouble.

Then edit /etc/gdm/gdm.conf-custom. Find the [security] section and add a line PamStack=gdm-2.20.

This is where you might have a problem. Instead of 2.20, you may need to try 3.18 (this is for 16.04).

find the [xdmcp] section and add a line Enable=true.

That should cause no trouble.

XDMCP is not particularly secure protocol so it is a good idea to make gdm refuse connections from other computers. Add a line gdm: 127.* in /etc/hosts.allow and a line gdm: ALL in /etc/hosts.deny.

This, you can choose not to do. If you care about security, I suggest you do it, but otherwise, I think you can leave it.
Now restart gdm by rebooting (probably the easiest way). If you see the GDM login screen, something's up. Check over the original guide and tweak some settings.
If you don't have a login screen, then get to a TTY and run X -query 127.0.0.1. If GDM comes up, kill it (get back to the TTY and kill it there).
Make a new user called monitor:
addgroup --gid 983 monitor
adduser --uid 983 --gid 983 monitor

Create a file (guide has no name specs) in /etc/udev/rules.d/my.rules and put in the following:
SUBSYSTEM=="input", OWNER="monitor", GROUP="monitor"

Some package installations:
apt-get install x11-utils xserver-xephyr

We need to separate the monitors with some aliases:
ln -s xmessage /usr/bin/xmessage0
ln -s xmessage /usr/bin/xmessage1

Log into the monitor user in the TTY and create ~/.xsession.
Put this inside:
runscreen () {
    # $1 = number
    # $2 = geometry
    local xpid winid k
    while :; do
        xmessage$1 -geometry $2 "Window $1" &
        xpid=$!
        k=10
        while \
            winid=`xwininfo -name xmessage$1|grep 'Window id'|cut -d' ' -f4` \
            && [ $k -gt 0 -a ! "$winid" ]
        do
            sleep 1
            k=$(($k - 1))
        done
        if [ "$winid" ]; then
            Xephyr :1$1 -parent "$winid" -dpms -keybd "evdev,,device=$3,$xkb" -mouse "evdev,,device=$4" -query 127.0.0.1
        fi
        kill $xpid
        sleep 3
        kill -9 $xpid
    done
}

# For some reason I was unable to set the following in xorg.conf
# We need to turn off power management of the main X server because it doesn't
# see either of the keyboards and the mice so it will enter power-saving mode
# after 10 minutes
xset s off
xset dpms 0 0 0
xset -dpms

xkb='xkbrules=xorg,xkbmodel=evdev,xkblayout=us'

# PS/2 keyboard and mouse
kbd1=`ls /dev/input/by-path/platform-*-event-kbd`
mouse1=`ls /dev/input/by-path/platform-*-event-mouse`

# USB keyboard and mouse
kbd2=`ls /dev/input/by-path/pci-*-event-kbd`
mouse2=`ls /dev/input/by-path/pci-*-event-mouse`

runscreen 1 1280x1024+1920+0 "$kbd2" "$mouse2" &
runscreen 0 1920x1080+0+0 "$kbd1" "$mouse1"

Remember to edit it to reflect your resolutions.
Run startx as the monitor user and see if it works.
This needs to be made to start at boot if it works, so add this to the end of ~/.profile (for the monitor account):
if [ "`tty`" = /dev/tty6 ]; then
    exec startx
fi

Kill the GUI and go to TTY6. Login as monitor and it should start up.
If that works, edit the file /etc/init/tty6.conf as root and replace the line starting with /sbin/getty with
exec /bin/login -f monitor tty6 </dev/tty6 >/dev/tty6 2>&1

If it works, but you want to also separate audio, the linked MultiSeatX guide has some stuff for you.
Please remember this may not work. I typed this up rather quickly and will hopefully edit it to be a bit more clear if necessary. I have adapted parts of the guide to be more up-to-date and increase the chance of success.
Good luck!


How can I create a user who can log in without a password (delete password in passwd command?) in 18.04.4 over ssh?

Looks like you successfully deleted B's password on your first try (sudo passwd -d B).
However, you're on the wrong track: Deleting a password prevents login under any circumstances; it does NOT enable autologin. Undo the damage by creating a new password for B.

How to enable autologin on a server (no GUI): How can I get autologin at startup working on Ubuntu Server 16.04.1?

How to enable autologin on a Desktop (with GUI): Edit /etc/gdm3/custom.conf.


Is Bluetooth smart supported? If so, how; if not yet, when?

BlueZ 4 (ubuntu bluetooth manager) version on earlier versions of Ubuntu didn't have support for Bluetooth Smart and therefore Logitech MX Anywhere 2 mouse couldn't work but Ubuntu 15.10 comes with BlueZ 5.35 version that supports Bluetooth Smart and Logitech MX Anywhere 2 mouse should work on Ubuntu 15.10.


Trying to install League on first Linux machine, Issue with getting wine packages

I has been awhile since I installed on my machine, and the league client and probably the installer has changed since then. That said here is how I did it.

Fist, do the winetricks installations specified by your link. Next, the exe installer didn't work. I extracted the files from the exe file and ran the msi file in WINE.

Note: Currently, the LoL launcher does not run in WINE. You have to run the game client directly.

I have not tested this recently, but an alternative to installing is to copy LoL directory from a windows machine. Paste it into your WINE prefix's c_drive. Remember to create an identical path.

Also see WINEhq for installation advise.


How can I get Movable Type 5 experimental package?

Currently, version 4.3.3-1 is in the lucid/10.04 repositories (4.3.4-1 is in the maverick/10.10 and natty/11.04 repositories). Debian does not have any 5.0 versions, and a quick PPA search on Launchpad did not turn anything up either.

You can download the latest version from the movabletype.org download page. The site also contains an installation guide.

If you would prefer to install movabletype-opensource from an actual deb package, you might be interested in this bug on the Debian BTS reporting that 5.0 is available upstream and requesting and updated package or this Request For Help Bug.


Pencil 2.0.9 opens a new firefox window instead of the software itself

I've just tested it and the same problem occurs with me (v2.0.9).

This is probably just a temporary problem. You should create a new issue. So you can best be helped.

Here is a quick hack:

Open the file /usr/bin/pencil in an editor:

sudo nano /usr/bin/pencil

and replace content with the following code:

#!/bin/sh

APP_INI="/usr/share/evolus-pencil/application.ini"
if [ -x /usr/bin/xulrunner ]; then
    /usr/bin/xulrunner "$APP_INI" "$@"
elif [ -x /usr/bin/iceweasel ]; then
    /usr/bin/iceweasel --app "$APP_INI" --no-remote "$@"
else
    /usr/bin/firefox --app "$APP_INI" --no-remote "$@"
fi

You can also build it yourself though, if you do not want to install the Firefox extension (Currently the latest version is 2.0.9):

wget https://github.com/prikhi/pencil/archive/v2.0.9.tar.gz
tar -xvf pencil-2.0.9.tar.gz
cd pencil-2.0.9/build
./build.sh linux

Start with:

xulrunner Outputs/Linux/application.ini

or

firefox --app Outputs/Linux/application.ini --no-remote


swapon -s

is the right command to control your swap. Swap is not displayed when invoking the mount command. free is another option to find out about swap.

Sample output:

swapon -s
Filename                Type        Size    Used    Priority
/dev/sda8                               partition   2056280 11080   -1

free
             total       used       free     shared    buffers     cached
Mem:       1025756     995180      30576          0      76648     238908
-/+ buffers/cache:     679624     346132
Swap:      2056280      11080    2045200

If your sd-card is always present and usable as swap, put an entry into /etc/fstab, and use swapon -a.


Last.fm is now a subscription service, so won't stream within Rhythmbox "for free". Took me a while to work this out, and comments about bait-and-switch are about right, it seems to me.


Try install pulseaudio after the installation fails follow below steps

sudo apt-get -f install
sudo apt-get install pulseaudio


"Connection error. Please try logging in again" login into Last.FM from Rhythmbox

I'd suggest upgrading to the latest version of Rhythmbox if you haven't already. The way I log in to last.fm is through a button in Rhythmbox that takes me to my browser in order to authenticate Rhythmbox and add it to the connected applications of last.fm, with no need to separately log in.


How to select by the word in the terminal with quick keys?

According to Thanatos on SuperUser Stack Exchange it looks like it is not possible to do that with the default gnome terminal.

There is nothing about word selection shortcuts in the gnome terminal preferences.

Please see this answer for further information.


Fresh Kubuntu 15.04 installation hangs on boot

I am using Ubuntu for the first time and have the same error while installing it on my system from scratch. I just had to wait for 2 minutes when the PC shows this error 4 times: error:/dev/sdb: no medium found and then it loads normally.


Finally solved.

From Guake Preferences, uncheck "enable popup notifications on startup".

Then add guake to Startup Applications and that's all.

Startup Applications can be found via the dash, this image shows an example of editing a startup but adding would be exactly the same.

If you want to easily find the path to an application you can issue the which command

$ which guake

Which would return

/usr/bin/guake


I found the answer myself.

You have to edit the file /etc/apache2/conf.d/localized-error-pages

sudoedit /etc/apache2/conf.d/localized-error-pages

You can enter plaintext or link to a script or html


ubuntu 12.04 and/or 12.10 can boot from software raid5?

I tried myself with 12.04.1 ubuntu server and... it works!!!

Three disks in software RAID5, no RAID1 needed for boot.


Java installation error using apt-cacher

Ok, finally I've found a solution in this post.

Adding

Acquire::http::Proxy { download.oracle.com DIRECT; };

in the proxy configuration /etc/apt/apt.conf.d/01proxy.


What is the best 2D driver for GeForce4 MX 440?

What is the driver that you are use? by "Hardware Driver"? If you use the "Hardware Drier" to download the driver, you might want to try using the open source driver, take a look on this: http://www.nvidia.com/object/linux_display_x86_96.43.11.html


How to install Eclipse latest version (Neon) on Ubuntu (CDT) and run NOT as superuser

You must change user owner and permissions of the installer. If the problems persist, try the same on the installation folder and files:

sudo chown <yourUserName> <file>
sudo chown -R <yourUserName> <folder>
sudo chmod 0644 <file>
sudo chmod 0644 -R <folder>

Where <yourUserName> is your user name, and <file/folder>  the file or folder to process.

Try to install Eclipse on a separated folder in your Home folder, for example: /home/$USER/Programs/Eclipse


Ubuntu Core 16 does not come with a default user name and password. Ubuntu Core requires you to setup a Ubuntu SSO account with your SSH keys, which enable you access to your device. Once in, you can create your own user. Please find the relevant instructions here.


I had the same problem. In my case, incorrect pulse config made that problem.
I fixed that problem by resetting that configuration by:

Rename pulse folder located at $HOME/.config to any name (just for backup the original)

Open your terminal and type the commands below:
pulseaudio --kill
pulseaudio --start


In the install hook for the charm, you can apt-get install all your dependencies or manually install them (Up to you).

Here is an example of an install hook from another charm:

http://jujucharms.com/charms/precise/mediawiki/hooks/install

Here is the documentation for writing a charm, this is a step by step guide on how to get started:

https://jujucharms.com/docs/stable/developer-getting-started


Audacity isn't playing any sound and it makes 30 tracks instead of one

Audacity has sound settings.

On the top left go to Edit Preferences Devices and in Devices choose which device you want your sound to play through.

Click OK and test to see if that solves your problem.  I'm using version 2.1.0 which you will find under Help and About Audacity at the top and that works.


They won't cause any serious issues unless they start multiplying at a faster rate.

This article is a good read:
- What Is a “Zombie Process” on Linux?

Zombies are basically the leftover bits of dead processes that haven’t
been cleaned up properly. A program that creates zombie processes
isn’t programmed properly – programs aren’t supposed to let zombie
processes stick around.

What’s a Zombie Process?
To understand what a zombie process is and what causes zombie processes to appear, you’ll need to understand a bit about how processes work on Linux.
When a process dies on Linux, it isn’t all removed from memory immediately — its process descriptor stays in memory (the process descriptor only takes a tiny amount of memory). The process’s status becomes EXIT_ZOMBIE and the process’s parent is notified that its child process has died with the SIGCHLD signal. The parent process is then supposed to execute the wait() system call to read the dead process’s exit status and other information. This allows the parent process to get information from the dead process. After wait() is called, the zombie process is completely removed from memory.
This normally happens very quickly, so you won’t see zombie processes accumulating on your system. However, if a parent process isn’t programmed properly and never calls wait(), its zombie children will stick around in memory until they’re cleaned up.
Utilities like GNOME System Monitor, the top command, and the ps command display zombie processes.
Dangers of Zombie Processes
Zombie processes don’t use up any system resources. (Actually, each one uses a very tiny amount of system memory to store its process descriptor.) However, each zombie process retains its process ID (PID). Linux systems have a finite number of process IDs – 32767 by default on 32-bit systems. If zombies are accumulating at a very quick rate – for example, if improperly programmed server software is creating zombie processes under load — the entire pool of available PIDs will eventually become assigned to zombie processes, preventing other processes from launching.
However, a few zombie processes hanging around are no problem – although they do indicate a bug with their parent process on your system.
Getting Rid of Zombie Processes
You can’t kill zombie processes as you can kill normal processes with the SIGKILL signal — zombie processes are already dead. Bear in mind that you don’t need to get rid of zombie processes unless you have a large amount on your system – a few zombies are harmless. However, there are a few ways you can get rid of zombie processes.
One way is by sending the SIGCHLD signal to the parent process. This signal tells the parent process to execute the wait() system call and clean up its zombie children. Send the signal with the kill command, replacing pid in the command below with the parent process’s PID:
kill -s SIGCHLD pid

However, if the parent process isn’t programmed properly and is ignoring SIGCHLD signals, this won’t help. You’ll have to kill or close the zombies’ parent process. When the process that created the zombies ends, init inherits the zombie processes and becomes their new parent. (init is the first process started on Linux at boot and is assigned PID 1.) init periodically executes the wait() system call to clean up its zombie children, so init will make short work of the zombies. You can restart the parent process after closing it.
If a parent process continues to create zombies, it should be fixed so that it properly calls wait() to reap its zombie children. File a bug report if a program on your system keeps creating zombies.


You have installed the 'snap' version of Knights which installs Knights 2.6.0 on Ubuntu 18.04. I can certainly confirm on my own system that there is an issue with this version where it does not allow online play with freechess.org.

The repository version is a little older at 2.5.0 but it works out of the box with online play. To return to this older version first remove the snap version:

sudo snap remove knights

and then install the older repository version:

sudo apt-get install knights

Now you can successfully play chess with other players on freechess.org! It might be material for another question as to why the newer version fails...


How do I have my internal microphone and headphones be used simultaneously under PulseAudio?

Install PulseAudio Volume Control from Ubuntu Software Center, which has a lot of options to choose from.

After installing, in application's "Output Devices" tab choose your headphones and in "Input Devices" tab choose internal microphone. By pressing green button you can choose which device will always remain as default (device which is not selected will be default, not the opposite)

You can also choose settings per specific application, start Skype call and go to "Recording" tab where you can select internal microphone and in "Playback" you can select headphones.

Additional option is to choose suitable profile in "Configuration" tab.


Inkscape installed by Snap. Where to put Inkscape's Palettes, Symbols, Extensions, et cetera?

Got the solution. I had to put the necessary folders in the folder

/home/myName/snap/inkscape/5874

You can add palettes, symbols, extensions etc. I can confirm that these 3 are working. I have also used " icons " folder, but it is empty at the moment. Hopefully it will work as well.


How to make YouTube fullscreen actually fullscreen?

Okay, this is one of those embarassing occasions when you discover what's going on just after posting a question...

It is because of my dual monitor setup. YouTube is seeing the size of both monitors together, but then shrinks it to fit on one for some reason.

It doesn't happen on videos that are available in HD (in fact if the video is available in HD even if you watch it at 480p or lower resolutions then it works, which is a bit strange).

It seems this issue has been around for several years and the easiest fix is to enable HTML5 mode in YouTube.


You need to either create a bootable usb drive from the downloaded image or burn it to a dvd.

https://help.ubuntu.com/community/Installation/FromUSBStick

https://help.ubuntu.com/community/BurningIsoHowto

Once you've done that, boot from your chosen medium and install to the target drive.

https://help.ubuntu.com/community/GraphicalInstall


ssh: connect to host localhost port 22: Connection refused

Fire this command:

sudo iptables -L

If you see that no traffic is allowed (i.e. no specific rules), then run the following command:

sudo iptables -A INPUT -p tcp --dport ssh -j ACCEPT

this command tells the system to allow incoming connections to port 22...and usually should solve your dilemma, specifically for ssh / sshd.

UPDATED as of July 31,2016:
iptables have nothing to do with ssh as an application, but on other hand, functions as router in allow the traffic to port 22. When using iptables, the system actually understand 'ssh' however, it's a shortcut within command line but, really, it's actually iptables INPUT -p udp -dport 22 while --dport means "destination port" (ssh uses port 22). This probably caused some misconception on seeing 'ssh' as if it's an appication, but really '22' as port.


Should I make a partition for Ubuntu before installing?

NOT FROM WINDOWS!!!

The Windows disk partitioning tool has the unfortunate habit of converting from a standard Master Boot Record (MBR) format to Microsoft's proprietary Logical Disk Manager (LDM) configuration, which Ubuntu's installer doesn't support. Thus, if you try to create a partition for Ubuntu in Windows, you run the risk of creating extra work for yourself, since you'll need to use third-party tools to convert back from LDM to a standard MBR-only configuration.

In fact, I'd go so far as to say that the Windows partitioning tool is one of the buggiest partitioning tools in common use today. I've seen it do other strange things, like embed a primary partition inside an extended partition (a definite no-no).

That said, I've heard of fewer problems with the Windows partitioner on GPT disks, which are used by the vast majority of computers that ship with Windows 8 and 8.1. Still, I recommend using the Windows partitioner as little as possible.

The one thing for which the Windows partitioner is likely superior to the Ubuntu installer's partitioner is in shrinking the existing Windows partition. Just shrink that partition, though; don't create new partitions! Leave that task to the Ubuntu installer. You can let it do so automatically if you want to use the defaults, or use the "Something Else" installation option to set up a separate /home partition or otherwise deviate from the defaults.


xfce4-settings-manager

Tab window manager--> keyboard


How to display more than 1 terminal simultaneously

You need Terminator:

sudo apt-get install terminator

For four terminals at start-up, do the following:

Start terminator
Split the terminal Ctrl+Shift+O
Split the upper terminal Ctrl+Shift+O
Split the lower terminal Ctrl+Shift+O
Open Preferences and select Layouts
Click Add and enter a usefull layout name and Enter
Close Preferences and Terminator
Open Terminator with this command:

terminator --maximise --layout=<your_layout_name>

or with this command:

terminator --maximise --borderless --layout=<your_layout_name>

Jump between the terminal windows with Ctrl+Tab.

You can assign your personal terminator command to Ctrl+Alt+T in Keyboard Settings > Shortcuts. (Thx @Wilf)

Of course you can also create a terminator.desktop file. Copy the original desktop file and make your changes:

cp /usr/share/applications/terminator.desktop ~/.local/share/applications/
nano ~/.local/share/applications/terminator.desktop


Migration from Exchange 2003 to Post Fix

I am not an Exchange expert, nor have I a lot of knowledge on MS software. But as far as I know (and others may know better), using the native Exchange protocols is only possible with MS software like Outlook. I did not find a way to export mailboxes this way except for creating .pst files (se e.g. Exchange Mailbox Backup). There are tools to export to IMAP servers like courier via Outlook (see e.g. Converting all your Mailboxes), but that needs you to install courier-imap (or any other IMAP server) somewhere.

If you want to have your Exchange mailboxes exported directly to a local mailboxfolder structure, the easiest way is to use the IMAP protocol, as Exchange is able to support that.

If you have access to Exchange and the necessary administration rights, enable IMAP in Exchange Server (see Enable IMAP4 in Exchange). Then on any PC/host with perllanguage installed (not necessary your postfix server; preferrable LINUX OS) you may use the IMAP-Tools as I stated in previous comments. For more info, read the Documentation, especially chapter 4.1 and 4.9.

Of course, in all those cases, you need to know the usernames/passwords of the users, or with some tools an administrative account in Exchange with Import/Export rights. And be prepared to invest some time; it's not that easy as it reads.


Webcam works in browser, but not in Skype or Cheese

Have the same model and also the same problem. It seem to be a bug but there is currently no solution for it https://bugs.launchpad.net/ubuntu/+source/cheese/+bug/1268359


How can I figure out the add-apt-repository command by looking at a launchpad project?

PPAs in Launchpad are connected to People/Teams, rather than projects. Your best bet is to click on the "Maintainer" for the project ("Cardapio Team" in this case):

From there, follow the link on under "Personal Package Archives" on their profile page. There may be multiple options here, you'll just have to use your best guess based on their names.

The name of the PPA will be on this page:

However, this is not guaranteed to work, as the developers can use any PPA they want for their project. It could be ppa:someunrelatedteam/foobar for all you know. There is no way to know for sure from the Launchpad project.

Alternatively, googling "[project name] PPA" tends to give good results.


How to make Nautilus remember the windows position?

One solution to this problem is using the software gnome-tweak-tool. Here is how step by step: (WARNING! read at the bottom of this message first: there will be some bugs if you follow the steps but it is fully and easily reversible)

1) if you do not have installed gnome-tweak-tool you can find it in Ubuntu Software Center. In the search area type "advanced settings" and install the first matching result.
Close Ubuntu Software Center.

2) This app will appear in Unity with the name "Advanced Settings", if not, search it with dash with this name.

3) Launch this app and go to "Desktop" and change "Have file manager handle the desktop" from OFF to ON. That's it! Close the app and now Nautilus will remember the last size and position.

WARNING! There are some side effects to this action, but it is fully reversibile if you put "Have file manager handle the desktop" from ON to OFF. Some bugs that I have noticed after the modification: slow unity, slow firefox and others.


Some lenses doesn't show up in Dash. For example, if you install the Calculator Lense, it will only appear if you type for example "2 * 3" on the search box. Some have "tabs" bellow the Dash. Just click on them and them you can make your search.


install/uninstall ASUS USB-AC56 on Ubuntu 20.04

I believe the best method is to obtain an internet connection by ethernet, tethering or whatever means possible, open a terminal and do:
sudo apt update
sudo apt install build-essential git dkms
git clone https://github.com/aircrack-ng/rtl8812au.git
cd rtl8812au
sudo make dkms_install
sudo modprobe 88XXau

Your wireless should now be working.


Both Spideroak and Crashplan have a linux clients.


How can I make ubuntu 14.04 virtual machines to use host machine JDK, SDK, JRE?

You can't ... The whole idea with virtual machines are that you run a guest-OS on top os, and isolated from, the host-OS.
And even if you found a way to break the isolation, you can't be sure that the updated packages from the host-OS will run in the guest. because of version differences.
The best solution would be to upgrade your vm's to a supported version.


Shutdown / Power off button does always go to suspend on 17.10

Try changing the HandlePowerKey= line in /etc/systemd/logind.conf. Yours might say HandlePowerKey=suspend. You can change it to say HandlePowerKey=poweroff.


Volume applet in the tray has gone. How can I get it back?

When you issue a command similar to the following, do you see indicator-sound-service?

ps ax | grep 'indicator'

In case the package was inadvertently removed, try the following:

or

sudo apt-get install indicator-sound


Install screen doesn't show on Ubuntu LiveCD/LiveUSB

Try Ubuntu Alternative Downloads
It's a non-graphical installer but the end-result is the same.


I found this answer to be helpful for a similar situation. I'm not really sure what the underlying bug is (either in adb or Genymotion), but until it gets fixed this is a suitable workaround. Essentially you're explicitly pointing adb to the device with adb connect ...


Installing EPSON GT-S80 Workforce scanner & printer drivers

This is not a printer, but scanner.

For scanner driver go to Epson drivers site

Search for your model, and download drivers.

You will need

 esci-interpreter-gt-s80_0.2.1-1_amd64.deb
 iscan-plugin-esdip_1.0.0-5_amd64.deb
 iscan_2.30.1-1~usb0.1.ltdl7_amd64.deb
 iscan-data_1.36.0-1_all.deb

if your system is 64-bit.

Copy these files to your home folder and run in terminal

sudo apt-get install *.deb
sudo apt-get install -f


How do I know what files are executed when I open an application?

Use strace!

Example: List all files opened by Firefox during a session:

strace -f firefox 2>&1 | grep 'open('

Results in something like this if you open a second instance of FireFox: http://pastebin.com/iRqxgiWN (The '-f' option just makes strace follow process forks.)

Example 2: List all processes executed by FireFox:

strace -f firefox 2>&1 | grep -P 'exec[vlpe]*\('

Results in something like this when visiting YouTube:

[pid 25020] execve("/usr/lib/firefox/plugin-container", ["/usr/lib/firefox/plugin-containe"..., "/usr/lib/adobe-flashplugin/libfl"..., "-greomni", "/usr/lib/firefox/omni.ja", "-appomni", "/usr/lib/firefox/browser/omni.ja", "-appdir", "/usr/lib/firefox/browser", "15198", "false", "plugin"], [/* 57 vars */]) = 0
[pid 25024] execve("/bin/sh", ["sh", "-c", "ps x | grep netscape"], [/* 57 vars */]) = 0
[pid 25025] execve("/bin/ps", ["ps", "x"], [/* 57 vars */] <unfinished ...>
[pid 25026] execve("/bin/grep", ["grep", "netscape"], [/* 57 vars */]) = 0

You can do this with many other system calls as well...

By matching the parameters of open() in your grep search you can also find out in which mode the file has been opened:

Just add | grep -P 'O_RDONLY|O_RDWR' (the leading pipe character is important!) to filter read access or | grep -P 'O_WRONLY|O_RDWR' for write access to your command...

EDIT:

As was mentioned in the comments you can also use strace -fe open firefox to list all files opened by FireFox. You can also use strace -fe trace=file firefox to list all file operations done by FireFox that have a file path as an argument (open, stat, lstat, chmod, access, ...).

Many more are available! Check out the strace(1) manual page.


Maybe this is not an issue of too little RAM, but of a CPU bottleneck? Anyway, what you can try, if you handle a large drawing, is to view the whole thing in Outline or No Filters mode (See View-Display Mode in the menu).

http://tavmjong.free.fr/INKSCAPE/MANUAL/html/View-Misc.html#View-Misc-OutlineMode


Edit lxc_root/etc/hostname AND lxc_root/etc/hosts replace u2 with myLXC or

sudo -i -e 's/u2/myLXC/g' lxc_root/etc/{hosts,hostname}

Be sure to edit the files in your lxc root and not the host


How to configure Git user name and email?

This answer is an addendum to the other answers, and although it answers the commands question like the other answers, it has additional information added which was not touched on in other answers.

As stated in other answers, the full commands to use are in the following format:

git config --global user.email "bob@bob-smith-industries.net"
git config --global user.name "Bob Smith"

As to what to put here specifically, that's up to you.  Keep in mind, however, where the git project resides.  If the Git project resides on GitHub, BitBucket, or a private GitLab instance, then in order for your commits there to tie to your username, your user.email configuration option should match an email address of which you have registered on those sites.

If the repository owner wants you to be using a specific name and address for yourself, then you may also wish to set this here as well.

Note that this affects every single git repository you use.  Most of the time people and projects don't care, but sometimes they do.  Make sure what you set here is 'OK' and valid for all the git projects you work on.


Did you try to open the powermanager and tick the box to allow the hdd to spin down whenever it is possible? Use powertop (you can find it in synaptics paketmanager) and increase dirty writeback as proposed by powertop. Pls report back if this reduced the temp.


My Dell Latitude D400 with Lubuntu 12.04 can find my wifi network... but can't authenticate the access. What could I check?

From your iwlist scan I can see that your router is set-up to use both TKIP and AES encryptions. I had similar problem before with one of my network cards (it was supposed to support both encryption methods) and the solution was to configure my router to use only TKIP.


How to add unallocated space to root partition

You need to resize first the extended partition

For an unknown reason, it does not take all the remaining space.

So click on sda3/extended and resize it to its maxium.

Then you will be able to resize the sda6 partition as you expect.


Stop sound when deleting files (or system events)

Sound Preferences
Set alert volume to mute.


No progress bar here: The delay is not from the tar process, but from the kernel I/O subsystem not quite being finished.
tar reads that archive file and writes it to the filesystem on your SD card, but that goes into kernel buffers first. The kernel reports to tar that the operation is complete, but it still keeps flushing those buffers to the hardware. Worse, most modern SD cards / USB sticks have some hardware buffer, too, that also needs to be flushed.
If you want to script that, you can send a sync command after your tar command; this will well and truly block everything until all buffers are flushed (written to the actual hardware):
tar -xvf myarchive.tgz -C /media/sdcard
sync

(Notice that tar is smart enough since many years to detect the compression method upon unpacking, so you can omit it for -x and -t)


Can I run Chrome stable and canary in parallel?

Chrome Canary builds are not available for Linux, so there's no way to get them running.


Transfer application files from Linux to iOS device?

You can transfer files to and from your iOS device using an app called FileApp:
https://itunes.apple.com/us/app/fileapp-documents-files-reader/id297804694

FileApp has a "share files over wifi" feature with clear instructions on how to transfer files.  To upload files to your device, you can use FileApp's simple web interface.  Use an FTP client like Filezilla (available in the Ubuntu software center) to copy files from your iOS device to your computer.

Edit: As mentioned in the comments below, once the file is loaded in FileApp, you can copy it to any app that is registered to handle that filetype through the actions menu. For example, video and audio files of most types (even those not normally supported on iOS) can be copied to VLC for Mobile for playback. After you have copied the file to the destination app, you can delete the original from FileApp to free up storage space.


snappy ubuntu core install basic packages

The workaround posted by Lin is fine on 15.04 but in 16.04 LTS you will have a different mechanism, called the 'classic dimension', that will give you a traditional deb based filesystem alongside the snappy filesystems. That way you can use git or other tools on a snappy system and pop back and forth between the snappy and classic dimensions.


You are missing a fi at line 18

read -p "If you are sure then type DUCKS in all caps. If not type that isn't DUCKS."
if [ "$REPLY" != "DUCKS" ]; then
        echo "QUACK..."
        exit 1
fi
gconftool-2 --set /apps/gnome-terminal/profiles/Default/title --type=string "Removing ads"

Quoting $REPLY helps too.


Can I make use of my ubuntu laptop to test ibeacon?

linux-ibeacon is a Python script that creates an Apple iBeacon-compatible Bluetooth LE beacon using a computer running Linux and a Bluetooth LE adapter. You need to install either Python 2.6 or Python 2.7 and version 5.0 or greater of BlueZ, the Linux Bluetooth stack and associated tools.

  In Ubuntu 15.10 and later (required for bluez>=5.0), open the terminal and type:

  sudo apt install python2.7 bluetooth bluez-tools blueman

  Your computer must also have a Bluetooth adapter (either built-in or USB) that is compatible with the Bluetooth 4.0 LE standard. To test whether your adapter is LE-compatible, run the following command:

  sudo hcitool lescan ## Start LE scan

  If you see either nothing, or a list of MAC addresses (aa:bb:cc:dd:ee:ff) then your adapter supports Bluetooth LE. If, on the other hand, you see any error messages in the output, then your adapter does not support LE. (This command will continuously scan for devices, so to exit it press Ctrl+C.)

  How to use it

  The command ibeacon works if:

  ibeacon is in $PATH
  ibeacon needs to be executable

sudo chmod a+x ibeacon

  filename should have no extension (i.e. ibeacon)
  shebang in the first line of script is needed(#!/usr/bin/python)

  Usage: sudo ibeacon [-u|--uuid=UUID or `random' (default=Beacon Toolkit app)]
                          [-M|--major=major (0-65535, default=0)]
                          [-m|--minor=minor (0-65535, default=0)]
                          [-p|--power=power (0-255, default=200)]
                          [-d|--device=BLE device to use (default=hci0)]
                          [-z|--down]
                          [-v|--verbose]
                          [-n|--simulate (implies -v)]
                          [-h|--help]

  This script must be run with root privileges in order to configure Bluetooth adapters. It is most convenient to run it using sudo.

  By default, the script creates an iBeacon whose UUID matches that which is used by the Beacon Toolkit iOS app, with major and minor both set to 0. These can be changed using the -u, -M and -m flags respectively. When specifying the UUID, you can specify an explicit UUID, or by specifying random the script will randomly generate a UUID.

  UUID, major and minor may also be specified by setting the IBEACON_UUID, IBEACON_MAJOR and IBEACON_MINOR environment variables, respectively. If a value(s) is specified both in the environment as well as a command line option, the command line option takes precedence.

  To test, you will need a device compatible with Bluetooth. In the Apple universe, that means the iPhone 4S or later, iPad 3rd gen or later (including Mini and Air), and the iPod touch. For Android, most phones made within the last 2 years or so should be BLE-compatible.) Then download either Beacon Toolkit (https://itunes.apple.com/us/app/beacon-toolkit/id728479775?mt=8) (for iOS) or iBeacon Scanner (for Android.) Fire up the app and begin scanning. Your newly-created iBeacon should appear in the list. If not, check to make sure that you specified the correct UUID, major and minor numbers. (For iOS devices, if you used a non-default UUID, you will have to enter it in the Beacon Toolkit app's settings screen.)


Stuck at boot screen, Nvidia graphics driver issues

I am hoping from the tag that you are trying to install Ubuntu 20.04. It appears that the desktop GUI environment is not properly configured. You can try the following steps once booted into ubuntu.

Press Ctrl+Alt+F1/F2/F3 to get to a terminal.
sudo apt-get purge nvidia* to clean previous nvidia drivers.
sudo apt-get install nvidia-driver-440 to fresh install the latest drivers.
sudo apt-get install gdm to reinstall Gnome desktop environment (or any other DE of your choice).
sudo dpkg-reconfigure gdm
sudo reboot to restart.


Difference between the results of the top command and System-Monitor,Why?

If you are referring to RAM usage, it is because system monitor does not include buffers and caching, just actual Ram used to run applications, top is slightly confusing because it does not obviously show disk usage after buffers / caching. Try using the following command :

free -m

See the image below, and note that the second line of free -m indicates available Ram, whilst the first line indicates actual Ram usage including disk caching.

I would recommend installing and using htop as it is better and simpler than top in my opinion.


How do I fill the current selection with color?

All you must do in GIMP is use the Fill Bucket tool, holding down shift will toggle between the 'fill similar color' and 'fill whole selection' options.


how do I video-record a narrated powerpoint-like pdf presentation?

I use vokoscreen and it does exactly what you asked for, recording voice and video of beamer presentation. You only need to configure it to record fullscreen and then choose the audio device (microphone).


Atheros Wifi works on one desktop computer but not another

Look into your logfiles:
 dmesg | grep ath
 grep ath /var/log/*.log* | egrep -iv path

Maybe issues with an interrupt. I could heal such a thing in the bios, but with intel-IPW2100. Maybe some other idea can be found.
update after comment:
On my older laptop, ubuntu 9.04, I get:
locate ath_pci
/etc/modprobe.d/blacklist-ath_pci.conf
/lib/linux-restricted-modules/2.6.27-14-generic/ath_pci
/lib/linux-restricted-modules/2.6.27-14-generic/ath_pci/ath_pci.mod.o
/lib/linux-restricted-modules/2.6.27-14-generic/ath_pci/if_ath.o
/lib/linux-restricted-modules/2.6.27-14-generic/ath_pci/if_ath_pci.o
/lib/linux-restricted-modules/2.6.28-16-generic/ath_pci
/lib/linux-restricted-modules/2.6.28-16-generic/ath_pci/ath_pci.mod.o
/lib/linux-restricted-modules/2.6.28-16-generic/ath_pci/if_ath.o
/lib/linux-restricted-modules/2.6.28-16-generic/ath_pci/if_ath_pci.o
/lib/modules/2.6.24-24-generic/madwifi/ath_pci.ko
/usr/share/linux-restricted-modules/2.6.27-14-generic/modules.alias.override/ath_pci
/usr/share/linux-restricted-modules/2.6.28-16-generic/modules.alias.override/ath_pci

On the newer one (10.04) only line 1, modprobe-blacklist.
But on both a lot of ath5k-files, mainly .ko-related (Kernel object, alias: driver).


It looks like they also have a built in tool to install the BIOS upgrades. In the Manual also provided on the ASUS site page A-15.

Download the BIOS upgrade from the link you provided.
Put the extracted file on a USB partition, using "FAT" file system not fat32 as stated here.
Plug in the USB, then turn on the computer, press the key to get into BIOS on boot.
From the Manual follow these directions:

  Use the Start Easy Flash function on the Advanced page of the BIOS Setup Utility. Follow the instructions shown.
  Locate the latest BIOS file and start updating (flashing) the BIOS.
  You must Restore Defaults on the Exit page after updating (flashing) the BIOS.

With this you should be able to upgrade your BIOS without Windows.


Installing KDE on Ubuntu, fails to fetch files because of versions mismatches

System with standard Ubuntu (with Unity) and a KDE desktop

This way you can get a system with standard Ubuntu (with Unity) and a KDE desktop, where you can select desktop environment at the login screen by clicking on the cog wheel symbol.

Install Ubuntu from ubuntu-16.04.4-desktop-amd64.iso
Make the system up to date with

sudo apt update && sudo apt full-upgrade

Install KDE-related packages

sudo apt install kde-plasma-desktop
sudo apt install kde-runtime
sudo apt install --no-install-recommends kubuntu-desktop

It might work too, if you use only the last line (I did not test that), but if you use it without --no-install-recommends there will be at least one serious conflict. The installation will fail, and there will be a black screen with a cursor instead of the KDE desktop. (Standard Ubuntu will still work.)

You can see that there are gnome application programs available via the KDE menu. But because of --no-install-recommends, several Kubuntu application programs are not installed. (Most of them can probably be installed, but it is was not done in this test.)

Alternatives

According to a comment, you don't want a live or persistent live system, but please consider the following alternatives.

Dual boot with separate Ubuntu system and Kubuntu system. Both systems are complete and can use the full power of the computer.
Ubuntu host system and Kubuntu guest system in a virtual machine. It is easiest to use VirtualBox to create the virtual machine. Both systems are complete, but the Kubuntu guest system cannot use the full power of the computer. This can be a good solution in a powerful computer.
Installation of Kubuntu in a USB SSD drive.Both systems are complete and Kubuntu can use almost the full power of the computer (a little slower than if in an internally connected SSD).


IPMI: MAAS automagically provisions BMC credentials - should I be concerned?

With e. g. ipmitool it is possible to directly access the ipmi controller using the /dev/ipmi0 device (or similar). Since this can be done only as root and locally, it does not require an IPMI user name and password. Presumably this is what MAAS does an deployment of a new machine.

As to how to define how MAAS creates an account for its own management needs I can not answer, but it should be possible to change later using this command:

$ maas-cli maas node update <system-id> power_type="ipmi" \
power_parameters_power_user=<user> \
power_parameters_power_pass=<password>

In any case: In general it is advised to set the default IPMI password to something sane and in addition have the LAN port of IPMI devices in a separate vlan or physical network.


server version where do I go to from command line interface prompt (DOS-type screen)

First I would like to welcome you to the world of Linux, once you start to get the hang of it you'll wonder how you ever lived without it.

As you installed the server edition you have a minimal installation, this gets the system running, but it is not very useful at this point.

To install software you will need to run sudo apt-get install <package-name> and then aptitude (the package manager) will do the rest. If you don't know the name of the package, you can always search for it using apt-cache search <search-term>.

To share files with your other machines (I'm guessing they are Windows) you need to install samba and get it up and running; it manages all of the connections to windows network shares (and more, if you should ever need it!)


Clean upgrade 16.04 (32 bit) to 64 bit Ubuntu

A similar question has been already asked about this subject:
Is it possible to "upgrade" from a 32bit to a 64bit installation?

Like it has been explained, the upgrade of Ubuntu (32-bit) to Ubuntu (64-bit) is for professional-level sysadmins therefore, I recommend you to be really careful with that. (Debian based systems 32-bit to 64-bit).

So, if you have a separated /home partition, the easiest solution would be to overwrite your / partition by doing an installation of Ubuntu 16.04 (64-bit) over it.

With that being said, if you absolutely want to do the migration and you don't have a /home partition, there is a straightforward way to do this migration: Quora - Migration 32-bit to 64-bit

P.S. If you don't mind loosing all your data, you should just then install Ubuntu 16.04 (64 bit), it'll be the quickest and easiest way possible.


What are implications of downloading buggy 12.04 iso

As someone who downloaded and did a fresh install last night, it's all good.


Using Nginx as a reverse proxy for a PHP site using Apache with URL rewriting

Just a suggestion, but your upstream app may also require the query string together with the original URI. You could try modifying your default URI as either:

try_files $uri $uri/ /index.php$request_uri;

or:

try_files $uri $uri/ /index.php$uri$is_args$args;

The nginx variables are documented here.


echo $DISPLAY won't work. If it did, you wouldn't need to set or export DISPLAY in the first place. You'll need to find out what the appropriate value is using some other way.

If you want to find out what DISPLAY your user is currently running, try:

w -h $USER | awk '$2 ~ /:[0-9.]*/{print $2}'

Then you can do:

export DISPLAY=$(w -h $USER | awk '$2 ~ /:[0-9.]*/{print $2}')

w lists the currently logged-in users and where they are logged in from, with DISPLAY being used for users logged in by GUI.
With awk, we match the second field, the location, to something that looks like a DISPLAY and print it out.


How

In the file /etc/default/grub, set the variable GRUB_INIT_TUNE to the tune you want.

For instance: GRUB_INIT_TUNE="2000 400 4 0 1 500 4 0 1 600 4 0 1 800 6"

Once done, apply your changes with sudo update-grub2.

Existing tunes

(The ones I could find)

Mario Bros. Mushroom Powerup: 1750 523 1 392 1 523 1 659 1 784 1 1047 1 784 1 415 1 523 1 622 1 831 1 622 1 831 1 1046 1 1244 1 1661 1 1244 1 466 1 587 1 698 1 932 1 1195 1 1397 1 1865 1 1397 1
Star Wars' Imperial Death March: 480 440 4 440 4 440 4 349 3 523 1 440 4 349 3 523 1 440 8 659 4 659 4 659 4 698 3 523 1 415 4 349 3 523 1 440 8
xiè-jìléi's tune (ascending): 2000 400 4 0 1 500 4 0 1 600 4 0 1 800 6
Adams's tune (rington-like to me): 480 220 1 277 1 330 1 440 1 185 1 220 1 277 1 370 1 294 1 370 1 440 1 587 1 330 1 415 1 494 1 659 1

More of them here.

Understand a tune

The syntax is: GRUB_INIT_TUNE="tempo [pitch1 duration1] [pitch2 duration2] ..."

  The tempo is the base for all note durations. 60 gives a 1-second base, 120 gives a half-second base, etc. Pitches are Hz. Set pitch to 0 to produce a rest.

Source: the grub documentation, the grub play command documentation (same page).

Preview / test a tune

If you want to test the tune: Install sox and use the script from that ubuntuforum.org thread (slightly modified by me to remove warnings):

grub-playtune

#!/bin/dash

if [ $# -lt 3 ]; then
    echo "Usage: $0 tempo freq dur [freq dur freq dur...]" >&2
    exit 1
fi

tempo=$1; shift

tmpdir=$(mktemp -d)

while [ -n "$*" ]; do
    freq=$1; shift
    dur=$1;  shift
    dur=$(echo "$dur*(60/$tempo)"|bc -l)
    sox -e mu-law -r 8000 -n -t raw - synth $dur sine $freq >>$tmpdir/grubtune.ul 2> /dev/null
done

play -q -c1 -r 8000 $tmpdir/grubtune.ul

rm -r $tmpdir

To make it executable chmod +x grub-playtune

Use example:

grub-playtune 2000 400 4 0 1 500 4 0 1 600 4 0 1 800 6

Frequency of a note

A python3-based script to compute the frequency of a note:

pitch

#!/bin/bash

python3 -c "print(*(int(0.5 + 440 * 2 ** (note/12)) for note in (${*/%/,})))"

Use examples:

$ pitch 0        # gives you A_4
440
$ pitch 2        # gives you B_4
494
$ pitch -2       # gives you G_3
392
$ pitch -12 0 12 # gives you A_3, A_4 and A_5
220 440 880

Frequency table

One is available here. It can also be generated, using the above script like so:

$ pitch {-12..0} # A_3 to A_4
220 233 247 262 277 294 311 330 349 370 392 415 440
$ pitch {0..12} # A_4 to A_5
440 466 494 523 554 587 622 659 698 740 784 831 880
$ pitch {12..24} # A_5 to A_6
880 932 988 1047 1109 1175 1245 1319 1397 1480 1568 1661 1760


If you interact with Language Tool directly, you first need to remove markup from the file --which is very tedious. Plus, it's hard to track the errors back to your original source file afterwards.

To solve this problem, I've just finished writing a new tool for checking spelling and grammar directly on LaTeX files, called TeXtidote:
The program can remove markup from the file and send it to the Language Tool library, which performs a verification of both spelling and grammar in a dozen languages. What is unique to TeXtidote is that it keeps track of the relative position of words between the original and the "clean" text. This means that it can translate the messages from Language Tool back to their proper location directly in your source file. TeXtidote produces an HTML report that shows your original sources, with the errors found by Language Tool highlighted at the correct location:

The tool is free and easy to install (OS-independent, requires Java). I encourage you to give it a try and tell me what you think!


Try Ctrl+ Alt+F1 to enter the terminal and login with your username and hit enter if you haven't given a password.


How to format usb drive which is not mounting on Ubuntu and windows? It also shows no partition

Did you try using gparted? Check if it detects the disk.

If it detects the disk, it should show some partitions or unallocated space. To completely reformat the disk-

Delete all existing partitions(if any).
Create a new partition table from Devices->Create Partition Table.
You can choose msdos (MBR) for this case, but GPT is required for >2TB sized disks.
Right click on the unallocated space and click New, to create a new partition.
Select the format, ntfs or fat32 if you want to use it on windows as well. Done


After looking at your last comment I looked up the specs and you are likely using a Qualcomm Atheros AR8171.

After Googling it looks like you want the alx module loaded during boot.

Try this:
echo 'alx' | sudo tee -a /etc/modules && sudo reboot

Note: I originally thought you wanted alc but I tested it and I could not get that to load in stock 18.04.3 off a fresh install.

alx does load, and per this page it looks promising.


How to make time/date program, shell model of program?

The reason why you are echoing the literal string  date is because you are using single-quotes.

To ensure that you echo the output of date you need to use back-ticks

i.e.

echo "Today is `date`"

This will output:

Today is Sun Apr  8 11:06:37 BST 2012


How to make python wait for a program to stop before going to the next line of code

Try subprocess.call instead of Popen. It waits for the command to complete.

import subprocess
subprocess.call('a.exe')
print("test")

For reference.


How to read symbol separated strings from a variable, convert to numbers, and perform arithmetic?

With bash, in an arithmetic evaluation context, variable names do not require the $ prefix. That means this is possible:

# set up the variables
hat=1 shirt=2 trousers=4
string="my_outfit=shirt+trousers"

# evaluate the equation
(( $string ))

echo $my_outfit

outputs

6


What's the 'envelope' icon in the top panel and do I need it?

That icon is called the Messaging Menu.

Messaging applications like your IM, mail, and chat can integrate with this menu so that it is obvious to you when someone is trying to get a hold of you. You can remove it by following these instructions:

How to remove the Mail icon indicator applet?


Try logging in as root with
sudo su
sudo -i
and then using the passwd command change the root password.


How can I find files from other partition running Ubuntu?

Maybe your partition isn't mounted on your Ubuntu system.
Type

sudo fdisk -l

and there you can show all partition table, types, sizes. You can mount using

sudo mount /dev/sdXX

where XX is number of partion (eg. sda5).

After you mount partion you can access all files from it.


End kernel panic: vfs: Vista unable to mount root fs on unknown-block (2, 0) HELP!

I encountered this error today for the first time, but with unknown-block(0,0).  Just prior to this error I got an error "attempt to read or write outside disk hd0".

The last time I rebooted it there was another error involving disk access which caused the boot process to drop down to the (initramfs) prompt.  That seemed to have been resolved by executing the recommended fsck and accepting all of the fixes it recommended.

All of this trouble started after upgrading the system to 16.04 LTS.

Probably relevant in all this is I'm running zfs mirroring two 3TB hard drives housing the /home content.  However, / is on its own drive along with the boot partition.

I've been running with this disk set up for several months without any disk errors until the upgrade to 16.04 LTS.

I was able to use my system again by falling back from 4.4.0-22, to kernel version 4.4.0-21 via the Grub 2 advanced menu option.  It then fell down to (intramfs) prompting me to do the fsck fixes again, which I did.  Upon reboot after fixes I had to, again, fall down to Grub 2's advanced menu option and fall back to 4.4.0-21.  If I tried to boot into the most recent update of the kernel (4.4.0-22) it gave me the "attempt to read or write outside disk hd0" again.

I was still having difficulty with apt, but that went away when I disabled Google's chrome repo.

I was then able to run the software update successfully.  Interestingly, it reinstalled the 4.4.0-22 kernel and demanded a restart.

After the restart the system came back up successfully.  But now I can't run any web browsers.  Firefox exits silently and chrome core dumps.


w3m doesn't show me images on Ubuntu. How to fix it?

First of all w3m-img package provides

  inline image extension support utilities for w3m

so it does not have separate executable.

Then visit web-site with inline images like

w3m http://w3m.sourceforge.net

and you will get something like

Note: it may not work on text TTY (Ctrl+Alt+F1) inside VirtualBox - I have seen this problem.


How to format hard drive without functional OS

Go in your BIOS and change boot order to boot first CD-rom (or bootable USB stick)
How do I install Ubuntu?


How to prevent sssd package from modifying nsswitch.conf

The solution on the bug report is to disable sudo support. From the link:

  As a workaround that doesn't require changing /etc/nsswitch.conf, you can also explicitely disable sudo support for your sssd domain :

[sssd]
services = nss, pam, sudo

[mydomain/LDAP]
sudo_provider = none

  This is easily fixed by manually removing sss from that line again. However, each update of the sssd package re-adds that unwanted entry, triggering another flood of mails before we manually remove it again.

An update should not change a configuration file. Configuration files contain specific directives for your system and not for all systems for all users. I would consider that a bug.


Do you have an encrypted home directory?

If you do then it is only decrypted when you are logged in.

Try creating a share for a directory that is not in your home directory and see if that works.


Why is there more than one command in Bash for accomplishing the same task?

It's called freedom!

It is the freedom to use what you think is right. It is the freedom to be creative. The freedom to not have to endure limitations of software companies. It is the freedom of having to think for themselves.

It's Linux!

Probably most of the programs are older than you and have their origins in Unix. But what is old, is not automatically bad.

And as you say in your comments:

  My concern is with whether similar commands violate the DRY principal.

This has nothing to do with DRY. Don't repeat yourself in your code, that's right. But fork code and change code; be creative!

If you need restrictions, use Microsoft, Apple or something else, but not Linux.

Read more here: Linux, GNU, and freedom.


The command for such thing is ssh [username@]servername -X where username@ is optional but useful in order to instruct SSH to use the right username in order to ask for the password only, after which all the GUI of your favorite applications will show up in your desktop instead of the remote desktop.

Additionally, you may wish to use SSHPass (Install it with sudo apt-get install sshpass in a terminal) in order to create custom SSH scripts which will allow you to connect to your server with a single instruction like this:

local.sh

#!/bin/bash
sshpass -p "PASSWORD" ssh username@server -p [PORT] -X

Let's say your SSH server has the 192.168.1.100 IP Address and the user is named webuser with a 12345 password, then the command will look like this:

sshpass -p "12345" ssh webuser@192.168.1.100 -X

Remember it is important that the -X must be uppercase.

After giving the proper execution permissions via sudo chmod +x local.sh you can invoke it in a terminal via ./local.sh

If you wish to go further, you can place this inside your /usr/bin directory so that you can invoke it in a terminal or launcher directly via local.sh or you can rename it to a single word command like sshlocal

Now. Once you are connected to the server, you don't need to open a terminal. All the commands are executed as if you were in a local terminal in the server. BUT: If you wish to execute gnome-terminal, a remote GUI for gnome-terminal will appear on you screen.

Give this a try and please inform if you succeed.

Useful information

 -X      Enables X11 forwarding.  This can also be specified on a per-host
         basis in a configuration file.
     X11 forwarding should be enabled with caution.  Users with the
     ability to bypass file permissions on the remote host (for the
     user's X authorization database) can access the local X11 display
     through the forwarded connection.  An attacker may then be able
     to perform activities such as keystroke monitoring.

     For this reason, X11 forwarding is subjected to X11 SECURITY
     extension restrictions by default.  Please refer to the ssh -Y
     option and the ForwardX11Trusted directive in ssh_config(5) for
     more information.

   -Y      Enables trusted X11 forwarding.  Trusted X11 forwardings are not
             subjected to the X11 SECURITY extension controls.

Source: http://manpages.ubuntu.com/manpages/precise/man1/ssh.1.html

Good luck!


How to check what has happened between booting Ubuntu and getting to the Desktop

You might give dmesg a try. I think it is the easiest way to do it. You can also try cat /var/log/syslog but that is less user friendly.


External monitor works initially in mirrored mode, but not in Extended mode - Ubuntu Studio 20.04 XFCE

Sometimes this is a hardware button issue. Have you tried Fn+F8 to toggle the monitor switching function? When you do, you should see a screen like this:

Choose the option that you would like and go from there. I've seen similar issues on Dell Vostro notebooks, so perhaps your G5 will respond just the same.
Hope this helps


eGalaxTouch calibration does not work at 12.04

I have now installed Ubuntu 12.10 because I have read this has better touchscreen support than 12.04. At 12.10 no additional driver is needed but the axis are inverted. I could not manage to invert the axis. Here is the new post with the new problem:

https://askubuntu.com/questions/246564/xinput-set-prop-does-not-work-for-touchscreen


AMD Catalyst Control Center crashes silently when I click 'apply' after changing dual monitor settings, unless run from terminal window

I've run into this problem before with a couple of distributions and the recurring theme is that the /etc/X11/xorg.conf file doesn't exist. (Note: Once I was able to get Catalyst Control Center to run I tried deleting my xorg.conf file and re-running the program and was still able to click Apply and have it work, so it's possible I'm talking out of my arse).

I couldn't tell you the technical reason as to why this is a problem (or why X works without the file) but as soon as I create a generic file with:

aticonfig --initial

I'm able to run the Catalyst Control Center and make changes to my layout.


Is there a way to check for sure what version of SATA on my laptop?

Check the system capability with
sudo dmesg | grep -i sata | grep -i ahci

and the current drive connection with
sudo dmesg | grep -i sata | grep 'link up'

Related:

https://superuser.com/questions/417857/how-to-find-sata-controller-version-on-ubuntu-laptop-do-i-have-sata-1-2-or-3
Identification of HDD by SATA port number
https://www.cyberciti.biz/faq/linux-command-to-find-sata-harddisk-link-speed/
How to check/enable the full speed of SATA drive/port?


WARNING: Module mcrypt ini file doesn't exist under /etc/php/7.2/mods-available

First install php7.1. Then copy mcrpyt.ini.

sudo apt-add-repository ppa:ondrej/php
sudo apt-get install php7.1-mbstring
sudo apt-get install php7.1-mcrypt
sudo ln -s /etc/php/7.1/mods-available/mcrypt.ini /etc/php/7.2/mods-available/
sudo phpenmod mcrypt
sudo service php7.2-fpm restart


Simple that:

# note the space between '~' and '/etc/folder1'
sudo 7z a -p /backups/`date "+%Y%m%d"`.backup.7z ~ /etc/folder1

You can give more than one target to put into a 7z file by simply statig each path for its own, separated by a '' (space). Example for better reading:

7z a <archive-file> <path1> <path2> ... <path_n>

Note: You can avoid backticks in your command by using $():

sudo 7z a -p "/backups/$(date +\%Y\%m\%d).backup.7z" ~ /etc/folder1


You could use socat:

socat TCP-LISTEN:25,su=nobody,fork,reuseaddr TCP-CONNECT:127.0.0.1:2525

This tells socat to listen on TCP port 25 and connect it to local 2525. It runs as the nobody user, for better security. The fork option means that it will renegotiate the incoming port, so that it doesn't block.

This is based on the following post:
https://superuser.com/a/536295/621970


How to install software in terminal in one line and one time?

This is what you want:

sudo add-apt-repository ppa:atareao/atareao && sudo add-apt-repository ppa:peterlevi/ppa && sudo apt-get update && sudo apt-get install my-weather-indicator  unity-tweak-tool variety

Purpose of &&:

let's say:

command one && command two

means execute the command two if and only if the  command one is successful.
This prevent errors so if some command failed for some reason then the next commands will not run, but if you want to run commands even if there is an error then replace && with ; so that command become:

sudo add-apt-repository ppa:atareao/atareao ; sudo add-apt-repository ppa:peterlevi/ppa ; sudo apt-get update ; sudo apt-get install my-weather-indicator  unity-tweak-tool variety


What's can I do if I just want to use python2 and without python3 to install some software?

Python 2 and Python 3 exist quite happily together in Ubuntu. I would not recommend uninstalling either as some programs rely on Python 3 and a lot more rely on Python 2 so  you will break your system.

You can find python 3 here:

/usr/bin/python3

and Python 2 here

/usr/bin/python2

or here:

/usr/bin/python

Both are equivalent

To run a python 2 program simply type:

python2 myprog.py

or

python myprog.py

For Python 3 it's.

python3 myprog.py

Replacing myprog.py with the name of your program.

You can also make an executable shell script the simplest python 2 program is probably

#!/usr/bin/env python
# Python 2.7
print "Hello, World!"

And the simplest Python 3 program

#!/usr/bin/env python3
# Python 3.6
print ("Hello, World!")

In each case the first line tells it what interpreter to use.  The second line is not needed but is a comment I like to have so I know which version of Python I am using.  The last line should be obvious.

You also need to make the file executable to avoid the need to type 'python' or 'python3' as appropriate to the version of Python you are using.


cannot access home wireless in ubuntu 14.10

Assuming that you successfully connect to other networks it's more likely to be your home router problem. The easiest solution is to reset your home router, if it's not a problem for you. Did you try just simply reboot your router? (I mean to disconnect it from rossete, wait for a couple of minutes and then plug it in again)


How to configure a U2F key(such as a YubiKey) for system wide 2-Factor Authentication?

Disclaimer: This guide changes the default PAM configuration which has the potential to lock you out of your computer. I take no responsibility for any badness that results from these instructions. As always, back up all files before changing them, have a live disk ready to revert changes if required and research anything you are unsure of to understand what is happening.
I have tested this with a YubiKey 4 and confirm it works. It should work with any security key that supports the U2F spec including most YubiKeys.

This is based on the Yubico guide with some changes to the scope of protection.

1. Install U2F tools from the Yubico PPA

First, enable the Yubico PPA and install the U2F PAM module:

sudo add-apt-repository ppa:yubico/stable && sudo apt-get update
sudo apt-get install libpam-u2f

2. Configure your key(s)

The Yubico guide creates the configuration in your home directory, but if your home directory is encrypted, you will be unable to access that on a reboot. To get around this, we need to create the configuration somewhere that isn't encrypted. This is up to personal preference, but here we'll create it under /etc.

pamu2fcfg | sudo tee /etc/u2f_keys

When your device flashes, touch the contact to associate the key with your account.

If you wish to add further keys to your account, then run the following command instead:

pamu2fcfg -n | sudo tee -a /etc/u2f_keys

(Having more than one key is a good idea: if your primary key gets lost or damaged, you still have access to your account using the other key(s).)

3. Test your key configuration

To test this configuration we will first enable it for the sudo command only. Remove the key from the computer and edit /etc/pam.d/sudo:

sudo nano /etc/pam.d/sudo

Add the following line below @include common-auth:

auth       required   pam_u2f.so authfile=/etc/u2f_keys

Open a new terminal window, and run sudo echo test. You will be prompted for your password, and then the command will fail. This is expected as your key is not in the computer.

Insert your key, run sudo echo test again. Enter your password and touch your key when it prompts for a touch, after which the your terminal should echo test.

This confirms a good configuration and we can continue to enable this for all authentication. Edit /etc/pam.d/sudo again, and remove the line we added.

4 Enabling 2FA for all authentication

This is the point where we deviate from the Yubico guide, as that covers enabling 2FA for GDM only, whereas we want to enable it for all authentication including TTY, SSH, sudo etc. First we need to edit /etc/pam.d/common-auth:

sudo nano /etc/pam.d/common-auth

Add the following line at bottom of the file:

auth    required   pam_u2f.so nouserok authfile=/etc/u2f_keys cue

nouserok means that a user without an associated key will not be prompted for 2FA and as such will still be able to log in. If you omit this option, then a user with no key will not be able to log in.
authfile tells the module to look for the file in /etc rather than the default location (home directory).
cue will prompt for a touch with a message ("Please touch the device").

(See Yubico's documentation for full list of options.)

At this point, we are finished. Any login attempt will be required to use a key for 2FA. The following is optional.

5. Disabling 2FA for sudo

Personally, I didn't want to have to use my key to run sudo. Disabling it was quite simple, though a bit messy. I am unsure of if there is a better way to do this. Edit the sudo pam file again:

sudo nano /etc/pam.d/sudo

Remove the line that says @include common-auth. Next, copy and paste the contents of /etc/pam.d/common-auth in the same place as the line we removed, but remove the line we added before enabling the U2F module. This last point is crucial: if you leave that line in, you will still need a key to run sudo. Removing that line removes the need for the key to run sudo.

You can adapt this procedure if you want to disable 2FA for ssh or other authentication scenarios. If you run ls /etc/pam.d, it will show the available files: each is named after the scenario that they control. Once again, don't do this unless you know what you are doing and backup files before you make changes.

6. Securing physical access

Of course, anyone can disable this by booting up with a live cd/USB drive and reverting your changes, so if your threat model includes physical access, you will want to enable full system encryption, disable USB/CD booting and set a BIOS password or another method to prevent third parties from tampering. Remember, you are only as safe as the weakest link in your configuration.


Download one of the installation ISO's, loop-back mount it, and serve it with a local HTTP/FTP server.

This will only work if you can boot the machine with a CD or USB, so no luck for you.

You could use a PXE installation, but that's non-trivial. If you don't know how to setup and configure DHCP/BOOTP, TFTP, and FTP/HTTP, look for other options.

Anyway, both methods are described in the source.

Source


Why do I get "wrong fs type, bad option, bad superblock" error?

The error message mentions:

  (for several filesystems (e.g. nfs, cifs) you might need a /sbin/mount. helper program)

This is relevant given that you are trying to mount NFS. The /sbin/mount.nfs helper program is provided by nfs-common. You can install it with:

sudo apt install nfs-common

On the other hand, if you are trying to mount CIFS, the helper program is provided by cifs-utils. You can install it with:

sudo apt install cifs-utils


Shortcut to return realpath of the symlink?

Try this command,

readlink -f $(pwd)

readlink reads the contents of a symlink, and readlink -f follows symlinks to symlinks to symlinks, etc., until it finds something that isn't a symlink.

So,

cd $(readlink -f $(pwd))

OR

cd $(readlink -f .)

The above commands allows you to go into the original directory.

Example,

~/Desktop$ ls -l
lrwxrwxrwx 1 avinash avinash        22 Mar  4 14:11 Pictures -> /home/avinash/Pictures

~/Desktop$ cd Pictures
~/Desktop/Pictures$ pwd
/home/avinash/Desktop/Pictures

~/Desktop/Pictures$ readlink -f $(pwd)
/home/avinash/Pictures

~/Desktop/Pictures$ cd $(readlink -f $(pwd))
~/Pictures$


EC2 added memory is not reflecting in the diskspace

I found the issue and fixed it. Diskspace was occupied by the deleted log file whose reference was kept by a process (in my case PHP).

Used lsof +L1 to check which process was keeping the reference and then run kill -9 processID to terminate the process and it will release the memory as well.


How to Loop using While and Quit after Success

Try with

i=1
while ! `adb connect 192.168.1.102:5555 >/dev/null 2>&1` ; do
  echo "Attempt $i) adb: Failed to connect!"
  i=$(( i + 1 ))
  echo "  I will try again in 5 seconds"
  sleep 5
done
echo "adb: Connection successful!"

The loop should exit if adb "successes" or if you press Ctrl+C.


Can I re-install windows without affecting Ubuntu?

You can install windows, just be careful that you understand which partition is for Windows and your Ubuntu and swap partitions.

You will need to restore grub

See: https://help.ubuntu.com/community/RecoveringUbuntuAfterInstallingWindows


Creating user account & pasting files in Desktop remotely?

Consider this an answer-in-progress, since more details are necessary on how you are adding users, whether it's the same username, etc.

Assuming you are creating a user with the same name and the same Desktop contents on each of the 200 systems, you need to do the following:

Pack the custom "Desktop" contents into a tarball, and upload it somewhere. Example:

Suppose the Desktop folder and other custom home contents are in /home/karthick/custom-folders
Archive with cd ~/custom-folders && tar -cvzf ../customfiles.tar.gz .
Upload customfiles.tar.gz to e.g. some HTTP server, say http://personal.karthick.com/

Here's the outline of the script to run on the target system to create the user with the custom folder:

sudo useradd --create-home customuser
cd /home/customuser
wget -O- http://personal.karthick.com/customfiles.tar.gz | tar -xz
sudo chown -R customuser:customuser *

More information that would be helpful to improve the answer:

Are you setting a password for this user? Will it be the same user?
How are you accessing the remote systems - SSH?


Why does the ubuntu password screen take longer on a wrong password?

Its for the security of the operating system. The arbitrary wait is to check brute-force attacks.

Duplicate Question: https://serverfault.com/questions/16232/ubuntu-linux-takes-longer-time-for-incorrect-passwords


How to get rid of panel indicator in Lubuntu 14.04?

It turns out this icon is related to the Logitech USB wireless mouse.  If you unplug the dongle, the icon goes away.  When the mouse battery gets low, the icon turns red.

That is an OK feature, but it would be nice if it was optional.  However, at this time, there is apparently no way to remove this icon, other than by using a wired mouse.


You mean the RC1 of 4.0.1, right?
You can get the steps here: http://www.libreoffice.org/get-help/installation/linux/

To summarise, you need to remove all the libreoffice packages presently in the system (easiest is using Synaptic)
Extract the tar.gz
Install using sudo dpkg -i *.deb from inside the DEB folder and desktop-integration folders.


Failed to start Light Display Manager on boot for Ubuntu 20

I got to Ubuntu 20.04 via an updated Ubuntu 18.04. I think something went wrong there. I did a fresh install after I did my backup of course.
Now everything works smooth again.


Boot off the LiveUSB and when you see the human logo  press the space bar.

When you get the alternate boot menu, select your language, then press F6 to bring up that menu and select 'nomodeset'.  Esc and select "Install Ubuntu"


No menu bar shown on the top panel after upgrading to 13.10

After other methods failed (unity-panel-service was not starting well), I was able to load the menu bar by placing a file menu_panel.desktop into ~/.config/autostart

menu_panel.desktop looks like this

[Desktop Entry]
Name=MenuBar
Comment=Start menu bar that fails automatically
Exec=/usr/lib/unity/unity-panel-service
Terminal=false
Type=Application
StartupNotify=false


Can I use a different graphical driver while booting, and the proprietery NVIDIA driver once my computer has started?

This is more of a workaround to what you are asking but it is as close as you are going to get
This is a old guide but still works as of 13.04
http://news.softpedia.com/news/How-to-Fix-the-Big-and-Ugly-Plymouth-Logo-in-Ubuntu-10-04-140810.shtml
I have a [NVIDIA GTX 550 TI] if you are wondering


Connection info shows correct DNS but resolvconf does not show the same

NetworkManager is the program which (via the resolvconf utility) inserts address 127.0.1.1 into resolv.conf. NM inserts that address if an only if it is configured to start an instance of the dnsmasq program to serve as a local forwarding nameserver. That dnsmasq instance listens for queries at address 127.0.1.1.

If you wish to see witch DNS you use currently type command

nmcli device show <interfacename> | grep IP4.DNS

You can set different DNS param for each connection

If you do not want to use a local forwarding nameserver then configure NetworkManager not to start a dnsmasq instance and not to insert that address. In /etc/NetworkManager/NetworkManager.conf comment out the line dns=dnsmasq

sudo nano /etc/NetworkManager/NetworkManager.conf

[main]
plugins=ifupdown,keyfile,ofono
#dns=dnsmasq

and restart the NetworkManager service.

sudo service network-manager restart

In this mode, NetworkManager updates /etc/resolv.conf (still via resolvconf) to include the nameserver addresses NetworkManager has for active connections.

If you want to disable the resolvconf mechanism for updating resolv.conf and just use a static resolv.conf file, do the following.

sudo rm -f /etc/resolv.conf  # Delete the symbolic link
sudo nano /etc/resolv.conf   # Create static file

# Content of static resolv.conf
nameserver 8.8.4.4
nameserver 8.8.8.8


Seems I needed to download the driver from Epson.  I downloaded the correct driver and installed it using the Ubuntu Software Centre. Everything worked fine.


Cant find Qt5Designer, qt5svg and qt5x11extras

To anyone else having the issue with qttools5-dev-tools not installing Qt Designer stuff try

sudo apt install qttools5-dev

instead (note there is no -tools at the end).

I was also lacking qt5svg and qt5x11extras, and these were solved with

sudo apt install libqt5svg5-dev

and

sudo apt install libqt5x11extras5-dev

respectively.


alias for command-line options not recognized

Aliases  allow a string to be substituted for a word when it is used
   as the first word of a simple command. (man bash, emphasis mine)

To create an alias for gcc with custom flags, do it like so instead:

alias gcc_flags='gcc -std=c99 -Wall -pedantic -Wextra -Wconversion'

And run your command as:

gcc_flags file_name.c -o object_name -L/usr/lib/i386-linux-gnu -lcurl

If there are options you keep adding every time and feel should be default, you can also add an alias for gcc itself, e.g.:

alias gcc='gcc -std=c99'

This way gcc will always be started with that flag. If you then want to ignore the alias and use it without that flag you can run it as \gcc or in a number of different ways listed in How can I run original command that aliased with same name?.


Is there a native SVP alternative for linux?

I guess you are interested in playing videos live without the need to process them first. In this case i can not really offer a solution but i want to point out that it is possible to enhance videos using SVP under linux using AviSynth and Wine.

http://jotschi.de/2015/08/12/svp-wine-linux.html

SVP also started a ingigogo campain in which they promote a linux version. I'm not sure whether this will include a player or not.


you will need to get a certificate from your university, i am not sure if all of them use the same one - mine is  AddTrustExternalCARoot.crt

you can try it, dl from here - https://www.dropbox.com/s/65dm62gcegrhbmx/AddTrustExternalCARoot%20%283%29.crt


You need to install firmware.

Distribution of Broadcom firmware is not allowed by Broadcom license. So you need to get it yourself. It is a bit complex, but there is no other legal way.

Download Broadcom Windows 8 driver or FROM HERE.

If your device is not listed in these drivers, you'll need to find a newer version of it somewhere. Broadcom removed the latest drivers from their site to make it more difficult.

Some laptop vendors have Bluetooth drivers on their sites, but some of them are not unzippable. So it is some quest. I could download the latest Broadcom drivers from their site, but it is not there any more.
Open this file by Archive Manager and find there bcbtums-win8x86-brcm.inf file. Name of the file may differ in some drivers. It can be bcbtums.inf located at Win32 or Win64 directory. It does not matter 32 or 64 bit to download.
Search this file for VID_0A5C&PID_21D7. These numbers are from your lsusb output

0a5c:21d7 Broadcom Corp. BCM43142 Bluetooth 4.0.

Comment: Some devices are not recognized as Broadcom BT in lsusb. If you are unsure which one is your BT device, run usb-devices command, it will give more detailed information. There you can find product and vendor IDs.

You will see some line ending with RAMUSB21D7

Search this file for RAMUSB21D7. You will find a section there like that:

[RAMUSB21D7.CopyList]
bcbtums.sys
btwampfl.sys
BCM43142A0_001.001.011.0122.0126.hex

That's what we are looking for. Name of the firmware file.
BCM43142A0_001.001.011.0122.0126.hex
Now extract that firmware from the same cab file.

Then you need to convert this file from hex to hcd format.
Download the tool for that

git clone git://github.com/jessesung/hex2hcd.git
cd hex2hcd
make

You will get hex2hcd folder in your home directory.
Place the firmware file to your home folder and run

~/hex2hcd/hex2hcd ~/BCM43142A0_001.001.011.0122.0126.hex ~/BCM43142A0-0a5c-21d7.hcd

You see that 0a5c-21d7 is id of your adapter from lsusb.

Important: For kernels 4.2+ you call this file as BCM.hcd instead.

~/hex2hcd/hex2hcd ~/BCM43142A0_001.001.011.0122.0126.hex ~/BCM.hcd

For kernels 4.8+ name of the file should be BCM-<VID>-<PID>.hcd, like BCM-0a5c-21d7.

For kernel 5.0 the file name is again BCM43142A0-0a5c-21d7.hcd

Now just copy BCM43142A0-0a5c-21d7.hcd, or another file according to the kernel version to /lib/firmware/brcm directory by

sudo cp ~/BCM43142A0-0a5c-21d7.hcd /lib/firmware/brcm

For kernels 4.2+

sudo cp ~/BCM.hcd /lib/firmware/brcm

For kernels 4.8+

sudo cp ~/BCM-0a5c-21d7.hcd  /lib/firmware/brcm

You can always check if the file name is correct by running dmesg | grep -i blue. There will be an error message if the file is not found.

If the requested file name doesn't match the file you created, rename the hcd file.
Turn your computer off and on again. Not just reboot!

Your adapter will get firmware and bluetooth should work.

All this looks complicated, but it is Broadcom lawyers to blame for that. Most of other vendors allow to re-distribute firmware under condition that it is done accompanied with the license.

That allows Linux maintainers to include firmware in distributions.

But not in case of Broadcom. That's why it is not done an easy way.

Many people could convert all hex files to hcd and make them available. Or just add them to the linux-firmware package of Ubuntu.

But it is not legal :-((


How do I enable automatic updates of all packages?

There is no -main, -universe, -multiverse, or -restricted repository.  Main, universe, etc are pockets within each repository.  Packages from all pockets in an enabled repository are installed.  There are only 4 repositories and they are all listed in that config file by default:

distro
distro-updates
distro-security
distro-proposed-updates

By default both updates and proposed-updates are commented out.  Simply uncomment the -updates line if you want all updates instead of only security related ones.


Rename multiple files with variable extensions to remove beginning and end of filename

I've written a bash script for you

#!/bin/bash
for file in *
do
 name=$(echo "$file" | tr '[:lower:]' '[:upper:]')
 name=AD${name#*_AD}
 name=${name::6}
 extension=${file#*.}
 mv ${file} ${name}.${extension}
done

With # I remove all the (smallest possible) part in front of the string that matchs *_AD.
In the next line I cut the Sting in max length to 6.
I write the extension by remogin the smales part that matches *..

Then we move the file to ${name}.${extension}.

Hope it works well.


Unable to make Window transparent in Ubuntu 12.10

finally I have solved the transparent window tittle problem using

dconf editor.
Anyone finding the same issue can find solution using my procedures.

instead of gconf-editor we have to use dconf-editor.

go to ..

dconf-editor --> org  --> compiz --> gwd

and set the value manually.
Works fine for me.


By upgrading to later Ubuntu versions. In Ubuntu 19.10, the previews behave as they should: the order is static rather than according to most recently used as in Ubuntu 18.04, so each time you click on the grouped icon, the same window stays on the same place.

Alternatively, you could remove the Ubuntu Dock, then install a more recent version of the Dash To Dock extension from the Gnome Shell extensions website. Ubuntu Dock is based on Dash to Dock, so the experience will be very similar. This, however, is not supported by the Ubuntu developers, so you venture on your own.


Xubuntu package broken : conflict between Open Office en Libreoffice

I figured the solution out. After being asked to install libreoffice-common, I ran "sudo apt-get install -f" and then "sudo apt-get -f install," finding a line in there somewhere that said "trying to overwrite ... which is also in package ..." I manually removed the package that was preventing the install using the directions found here (trying to overwrite 'file', which is also in package '*', how to solve?). After that, I was able to install the other package that I wasn't able to before, and everything cleared up.


Any way to get a faster program start in Unity?

Have you considered installing Preload?

sudo apt-get install preload

Preload is a daemon that monitors the programs you often run and partially loads them into memory. It particularly helps me with heavy programs such as Inkscape.


LibreOffice can not save documents on shared SSH drive - all other applications can

should be fixed with https://bugs.launchpad.net/ubuntu/+source/libreoffice/+bug/792622
in LibreOffice 3.5.3 (default in Ubuntu 12.04).


How to get working Firefox bookmarks scope?

I found the answer: I only had to enable the "Web" category on the result filter panel of the dash, it was not enabled by default (see screenshot below).


(Found at http://en.libreofficeforum.org/node/1697 )

Check your settings at:

Tools > Options... > LibreOffice Writer > Formatting Aids "Display of"

Check the box for "Paragraph Ends" or whichever non-printing character you want to view or hide by toggling. If all the boxes are unticked, you'd not see any non-printing character (which may explain why nothing changes when you click the button or use ctrl+F10).


Do you need a plugin for that? If you want to, you can just make a new directory in your home, call it .backup_hostname, use it in Daja Dup and sync it? (Only the Ubuntu One-folder is synced between all computers by default)


WIFI Mediatek MT7630 not working on ubuntu 14,04, need help

I had an asus with this mediatek 7630 wifi problem

I used this:

http://community.linuxmint.com/tutorial/view/1796

And it helps....


No. You should ask someone with an access to physical device to enable this.

Or you can use something like Qemu with software virtualization which may be slow depending on the power of your system.


Http server in Ubuntu is not reachable in same network

Are you duel booting?  Is that how you are testing your windows web server?  If you're doing something like a virtual machine (e.g. VirtualBox), answers might be different.

Back on your linux server, type the following command:

sudo netstat -tlnp

This will show you all ports that are either waiting for connections or already connected.

You can use grep to filter to port 80 thusly:

sudo netstat -tlnp | grep 80

If port 80 is indeed open, but you still can't access the web server, see if the web server is receiving traffic at all by running tcpdump:

sudo tcpdump 'port 80'

Leave that window open and then visit your server.  If the prompt doesn't move, something is blocking your connection.  You may have a firewall or something blocking your connection.

If it does move, provide the output and we can investigate further.


Startup lag when playing audio on Bose NC 700

It seems like it was due to the bluetooth dongle. I purchased a different one specifically made for audio transmission and it seems to be working fine now.


gnome-terminal: run command and stay open?

Passing the command in quotes works sometimes, but doesn't show anything.
gnome-terminal -- "ls -a"

Try updating terminal first. Then you may try --wait option. Comment if it works.


I had a similar issue before. Try to remove flash first by running the following command in a terminal:

 sudo apt-get purge adobe-flashplugin

Then try to reinstall flash with this command:

sudo apt-get install flashplugin-nonfree

That worked for me.


How do I track down changed dependencies for Bugzilla?

You have to install packages available for 20.04 LTS with
sudo apt-get install apache2 mysql-server libappconfig-perl libdate-calc-perl build-essential libdatetime-timezone-perl libdatetime-perl libemail-sender-perl  libemail-mime-modifier-perl libdbi-perl libdbd-mysql-perl libcgi-pm-perl libmath-random-isaac-perl libmath-random-isaac-xs-perl  libapache2-mod-perl2 libapache2-mod-perl2-dev libchart-perl libxml-perl libxml-twig-perl perlmagick libgd-graph-perl libtemplate-plugin-gd-perl libsoap-lite-perl libhtml-scrubber-perl libjson-rpc-perl libdaemon-generic-perl libtheschwartz-perl libtest-taint-perl libauthen-radius-perl libfile-slurp-perl libencode-detect-perl libmodule-build-perl libnet-ldap-perl libauthen-sasl-perl libfile-mimeinfo-perl libhtml-formattext-withlinks-perl libgd-dev libmysqlclient-dev graphviz python3-sphinx

and then simply rely on Bugzilla's install script from bugzilla directory:
./checksetup.pl --check-modules
sudo ./install-module.pl --all


How to make Shutter as the default screenshot tool?

For Unity (up to Ubuntu 17.04)
We need to install CompizConfig Settings Manager (CCSM) to bind Print and Alt + Print to Shutter. Follow these steps:

Install compizconfig-settings-manager .

Open Dash (press Super) and query for ccsm and hit Enter to run CompizConfig Settings Manager.

Under the General Category, you would find the option called Gnome Compatibility. Click on it (not the Checkbox beside it, ie; keep the checkmark activated).

Now switch to the Commands Tab and modify the text fields as shown in the following image.

Explanation of previous step. You can run man shutter in terminal to see what are the different CAPTURE MODE OPTIONS available.

Screenshot command line: shutter -f - This captures the entire screen. Activated when you press Print.
Window screenshot command line: shutter -a - This captures the current active window. Activated when you press Alt + Print.

Enjoy taking screenshots with Shutter!!