How to Record Screen and internal Audio?

SimpleScreenRecorder did the trick for me when recording online playing videos. It has an (experimental) OpenGL feature.
In Ubuntu:

sudo add-apt-repository ppa:maarten-baert/simplescreenrecorder
sudo apt-get update
sudo apt-get install simplescreenrecorder

With the OpenGL feature you can select to record an specific application window. So you can  even keep working while recording in the background. Don´t play any music though, because the audios will mix together (unless, of course, U R a DJ ;) )


How to Install Flashforge FlashPrint 3D app in Ubuntu

I was able to install the .man file by simply changing the name of it from .man to .deb (I am running PopOS, which is largely based on Ubuntu.), and my system immediately recognized it as a Debian binary.

The way I figured this out was simply using the file command to determine the filetype.


Um, no, this is wrong. You assign something to the variable $response and then pipe this assignment to zenity. Try

process | tee /tmp/response.txt | zenity --progress --pulsate --auto-close
response=$( cat /tmp/response.txt )

That way, the output will be stored in the file /tmp/response.txt, which you can later read into a variable.


Cairo-dock wrong position after recent reboot on 16.04 LTS

I too have a multiple monitor system and had a similar problem where the dock appears at the top of my screen (it was set for the bottom of my main screen) but is not apparently responsive to mouse hovering or clicks.  After some effort I realized my mouse can activate the dock, but not by hovering over the location where the dock appears to be, but at a location on one of my other screens!  After some experimentation I found that I can enter the Cairo dock configure menu by right clicking this other location in slightly different positions (I usually have to right click on a space between the docked apps to do this) until the  Cairo dock configure menu appears.  From there I have used the position plugin to change the dock position away from the screen edge and that has fixed the problem for me.  I am using a NVIDIA card and proprietary drivers with four screens and Compiz under Ubuntu 16.04 Unity.


OK, finally able to boot it with my dad's optical drive. It interestingly enough booted with my optical drive as well but it was so darn slow!!! For anybody wanting to change theirs it's super easy as the iMac G5 has a slim optical drive inside, just like a laptop one.


ACPI error when trying to make dual boot with Ubuntu 18.04 and Windows 10

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi=strict"

Is way better, and changing timeout from 90 seconds to 3 seconds stopped the still less frequent recurring errors from making booting or shutting down unbearably long or even forever.
Edit: I forgot how and googled it for you
sudo gedit /etc/systemd/system.conf
and change the defaul unbearable 90s to 3 (in my case)

DefaultTimeoutStartSec=3s
DefaultTimeoutStopSec=3s


If you want to use Debian or a Debian based Linux distribution, then you should have a look into the free Debian Administraor's Handbook: http://debian-handbook.info/

You can also have a look at Debian Administratrion Site:
https://www.debian-administration.org/

About services, there are some examples in both sites.  But you should have a firewall in your server. I would recommend ufw(1) as a good firewall for a server for you to have a look at.

An alternative to VPN you could also use is IPv6, and let gogoc(8) mannage a IPv6 tunnel.  But you still need to have a firewall.

You might also want to look at OwnCloud as a file/cloud server.


How to set a variable to a random value with bash

One easy method is to use $RANDOM to retrieve a pseudorandom 16 bit integer number in the range [0; 32767]. You can simply convert that to [0; 1] by calculating modulo 2 of the random number:

echo $(( $RANDOM % 2 ))

More information about Bash's $RANDOM: http://www.tldp.org/LDP/abs/html/randomvar.html

With that simple construct you can easily build powerful scripts using randomness, like in this comic...


What the command did was set the channel of Xfwm4 property of /general/vblank_mode to glx.  The default setting for that is auto.  To set it back run the following command:
xfconf-query -c xfwm4 -p /general/vblank_mode -s auto

If you just run xfconf-query -c xfwm4 -p /general/vblank_mode it will show you what the setting is.
Hope this helps!


How to install LLVM 12 for Ubuntu 16.04?

You can install llvm-12 as follows:
printf "deb http://apt.llvm.org/xenial/ llvm-toolchain-xenial-12 main" |sudo tee /etc/apt/sources.list.d/llvm-toolchain-xenial-12.list
wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key |sudo apt-key add -
sudo apt update
sudo apt install llvm-12


Use GNOME Tweaks Tool/Unity Tweaks Tool
Fonts > Scaling Factor


You'd have to have the linux headers from your kernel installed. For 13.04 the linux-headers-3.5.0-... is not in the official repositories, so you'll have to get it elsewhere.

With any nvidia issues, it's best to purge all installed drivers and try to reinstall them.  sudo apt-get purge nvidia*and then sudo apt-get install nvidia-304 when you're running the kernel you want them to run on.

If this doesn't work, you'd have to purge them again and build the nvidia kernel module from source, when running this kernel. Notice that it's not installed with a package, so when you want to remove these modules again when you plan on updating the kernel, you'd have to run the nvidia specific removal tool.


What is the command to search for 64-bit installed Java, JRE or OpenJDK?

First of all, apt-cache search does not search for installed packages, it looks for available ones, both installed and not installed. Also, the various search patterns you see are not mutually exclusive, so lines matching any of them will be printed. Finally, the ? after ^(ia32-) means ia32- is optional, the expression will match lines that have it and lines that don't. So, your command will indeed work for 64 and 32 bit systems.

The equivalent command to look for installed packages only would be:

dpkg -l *java* | awk '{print($2)}' |
    grep -E -e '^(ia32-)?(sun|oracle)-java' -e '^openjdk-' -e '^icedtea' \
      -e '^(default|gcj)-j(re|dk)' -e '^gcj-(.*)-j(re|dk)' -e 'java-common'

But don't use that. In Debian derived systems such as Ubuntu, there is a special tool for this, update-java-alternatives which, when run with the -l option will list installed Java environments:

 update-java-alternatives -l

On my system, for example, this prints:

java-1.6.0-openjdk-amd64 1061 /usr/lib/jvm/java-1.6.0-openjdk-amd64
java-1.7.0-openjdk-amd64 1071 /usr/lib/jvm/java-1.7.0-openjdk-amd64
jdk-7-oracle-x64 317 /usr/lib/jvm/jdk-7-oracle-x64


What is the best way to convert or copy an VM image into an lvm?

There is a short discussion at serverfault, hope it helps :-)


error while loading shared libraries: libXtst.so.6: cannot open shared object file: No such file or directory

The error above shows that AutoMouseClick did not ship with the required library. This is not your fault.

While xdotool doesn't have a nice gui, it is very flexible an powerful. Be aware that it will only work under X and not wayland. If you are willing to dig a little bit xdotool should far surpass AutoMouseClick for your needs.

If you would open a terminal and run man xdotool. You can read about using xdotool to send any valid keystroke or mouse action to the selected window. The following are a few of the examples from xdotool's man page.

Example: Send ctrl+c to all windows matching title "gdb"

xdotool search --name gdb key ctrl+c

Example: to type 'Hello world!' you would do:

xdotool type 'Hello world!'

Activate firefox and do a web search in a new tab for text in your clipboard

xdotool behave_screen_edge --delay 1000 top-left \
   search --classname Navigator \
   windowactivate --sync key --delay 250 ctrl+t ctrl+k ctrl+v Return

Emulate focus-follows-mouse

xdotool search . behave %@ mouse-enter windowfocus


This answer belongs to brandonchecketts.

Assume You have two hosts named as Host-A and Host-B. Now we are going to create a SSH Tunnel between these two and make sure that Tunnel is up & live for all the time.

Configuration Need to be done for Host-A:

Open your terminal , turn into root and paste the code one after one

useradd -d /home/tunnel tunnel
passwd tunnel
su - tunnel

next step is about creating a SSH key

In the terminal paste as

ssh-keygen

and then choose default choice for all prompt and copy the key with

cat /.ssh/id_rsa.pub

Now this time we have to configuration for Host-B

Open your terminal and execute these commands

useradd -d /home/tunnel tunnel
passwd tunnel
su - tunnel

and in terminal type as

mkdir .ssh
vi .ssh/authorized_keys

It will open a file in terminal and paste the above copied key from Host-A.

Now in the terminal type as

vi /home/tunnel/check_ssh_tunnel.sh

and paste as

createTunnel() {
    /usr/bin/ssh -f -N -L13306:hostb:3306 -L19922:hostb:22 tunnel@hostb
    if [[ $? -eq 0 ]]; then
        echo Tunnel to hostb created successfully
    else
        echo An error occurred creating a tunnel to hostb RC was $?
    fi
}
## Run the 'ls' command remotely.  If it returns non-zero, then create a new connection
/usr/bin/ssh -p 19922 tunnel@localhost ls
if [[ $? -ne 0 ]]; then
    echo Creating new tunnel connection
    createTunnel
fi

save and close and make it executable with

chmod 700 /home/tunnel/check_ssh_tunnel.sh

and then run the script, it will start a Tunnel with remote PC.

Read that above link, it is must.


How to run python script at login screen?

I'm not 100% sure of this, but i recall that i have used /etc/rc.local in similar situations. add a line that executes your script there.

And then there is upstart that might work. But i have no experience with that except a script that i found to autostart deluged

Your startup script would probably look something like

start on startup

script
  python - <<END
    import dbus

    bus = dbus.SessionBus()
    proxy = bus.get_object('org.gnome.SettingsDaemon',
                   '/org/gnome/SettingsDaemon/Power')
    iface = dbus.Interface(proxy,dbus_interface='org.gnome.SettingsDaemon.Power.Screen')
    iface.SetPercentage(0)

  END
end script

Upstart resource http://upstart.ubuntu.com/


Nothing is listening on port 80 anymore. That iptables command just forwards requests to port 80 on an external network to port 3000 locally.

But the service is still only listening on port 3000, and nothing else is (apparently) listening on port 80, which is what is being reported by your system.

My guess is that you are testing this locally (i.e., with a browser on the same machine as the service). If this is the case, and localhost:3000 reaches the service, then the iptables rule is not being reached because the request is not coming on an external network (or some other iptables related reason -- I am assuming here that your rules are sound and working, but you should check this.)

Possible solutions:

Ensure that all traffic is going through this iptables rule, or create multiple rules so traffic from all sources for port 80 is redirected to 3000.
Change the service so it binds to port 80, and remove the iptables forwarding stuff.


How do I change the default hyperlink color?

In your ~/.config/zim/style.conf(copy if from /usr/share/zim/style.conf) change it from blue to whatever suits you.  Reference here.

[Tag link]
foreground = blue
#underline  = single


HDMI Output Causes Streaming Media to Play Slowly

Look like the same problem:  Sound like half speed after suspend

Try to upgrade to latest daily Alsa driver as shown here : dkms Alsa HDA Intel

You have to download package from here : clic the arrow from   package   containing "xenial" in  its name, scroll down to "package files" , download .deb file  and install it using software manager or command line (sudo apt-get install filename.deb) , then reboot .

There are 2 Xenial packages: the first one in the list is more recent, may be better .


How to point to a steam library using snap version of steam?

I learned that you can't give snap permissions beyond what it haves, its hard-coded in it's source somehow.
I what did in the end to circumvent this was mount my hdd on /run/media which snap can access.

sudo mkdir /run/media/hdd
sudo chmod -R 777 /run/media/hdd

And then used the gnome-disk-utility to edit fstab to always automount the hdd in /run/media/hdd.

lastly to snap see the hdd:

sudo snap connect linux-steam-integration:removable-media core:removable-media


Ubuntu 18.04 PC boots to black screen and is unresponsive after installing AMD_GPU_PRO drivers for 7870XT drivers

Try Ctr+Alt+F2 when you get the black screen and see if this drops you to a terminal session.
If this doesn't work try to boot directly to a shell interface, i.e to command line without a GUI at all, no display manager or windows manager whatsoever. You can achieve this through 'Advanced options for Ubuntu' in the grub menu during boot. To make the menu appear see here.
From the command line you can uninstall the driver you installed, for how to do it see here. Then just reboot and it should work (to reboot from the command line just type "reboot" and hit enter).


Can't locate a directory using "locate"?

The binary database used by locate (/var/lib/mlocate/mlocate.db) is updated once daily by cron, so locate will not find new files.

You can fix this by first running sudo updatedb

sudo updatedb && locate -e bench-repo

It's a good idea to use the -e flag so you only find files that still exist.

Oh and here's a bonus tip - you can get locate to give you a detailed listing by passing to ls -l

ls -l $(locate -e bench-repo)


Add a virtual interface to the same subnet and route both

You can also do it this way. This method is better for newer ubuntu systems.

auto eth0
iface eth0 inet static
    address 192.168.1.50
    netmask 255.255.255.0
    broadcast 192.168.255
    gateway 192.168.1.1
         # the "up" lines are executed verbatim when the interface is brought up
    up ip addr add 192.168.1.2 brd 192.168.1.255 dev eth0 label eth0:0
    up ip addr add 192.168.1.3 brd 192.168.1.255 dev eth0 label eth0:1


Is it possible to extend my "computer" partition?

Extend computer Partition
You should boot from a Live USB, not the OS whose partition is being worked on.

Open GParted, select the HDD from the dropdown upper right.

Right click the 150GB partition and select Delete.

Click the green Apply check mark.

Right click the 40GB partition and select Resize/Move.

Stretch the partition to fill the empty space, leaving 1GB on the right to increase the swap space. Stretch the swap to fill the space.

Click the green Apply check mark.


Total newbee, Mac, is 222GB too much space in partition?

Most computers operating systems, even in Virtual Systems, are not very limited in how big a hard drive space they can manage. The only limit is perhaps the filesystem used - so for example, if ext4 is used , the maximium sensible limit is 16 tebibytes (roughly 1099 GB, 1024 GiB)

So as long as you have a space for Ubuntu of at least 10 GiB, it should be fine for most uses. I generally use a minimum of at least 50 GiB for the root system on installations I do (with at least 40 GiB for the home and up to 8 GiB swap space) - having a larger space available is not a problem and is usually a benefit, though you will want to leave some free space available for the Mac system.


iwlwifi Wifi Microcode SW error detected (Ubuntu 18.04 x64)

Try to create a configuration file, like so:

echo "options cfg80211 cfg80211_disable_40mhz_24ghz=Y" > /etc/modprobe.d/cfg80211.conf


MySQL change datadir, problem with mysqld.sock

you can do this:

cd /var/lib/

tar -cf - mysql | (cd /new_path ; tar -xvf -)

then (because it's always a good idea) make a back up.

 mv /var/lib/mysql /var/lib/mysql.old

then a symlink

 ln -s /new_path/mysql/ /var/lib

in that case you dont need to touch the /etc/mysql/my.cnf.


USB keyboard not writing an additional language on Ubuntu 20.04

In case it helps anyone else, I managed to solve it (trial and error...)
In the settings of input sources, I dragged Hebrew to be above English, and then the Hebrew input started working on the external USB keyboard.


How do I install one or more versions of MySQL and switch between the versions when I need?

You can only have one version of MySQL on the same machine using apt-get.

I would install all MySQL versions using docker. They have instructions on their site.

Docker you can install from apt-get or with ...

curl -sSL https://get.docker.com/ | sh

Downloading and setting up 5.5 rerouting port 3306 to 3406:

sudo docker run --name MySQL55 -p 127.0.0.1:3406:3306 -e MYSQL_ROOT_PASSWORD={password} -d mysql:5.5

{password} is used to set the root password; so change this.
You can use this to create another one for "5.6", "5.7", "latest" etc. The 5.5 at the end is the tag for docker; see the link for more tags. Supported tags:

8.0.3, 8.0, 8 (8.0/Dockerfile)
5.7.21, 5.7, 5, latest (5.7/Dockerfile)
5.6.39, 5.6 (5.6/Dockerfile)
5.5.59, 5.5 (5.5/Dockerfile)

The link has tons of info on how to connect and use different docker containers.


Kubuntu -- text snippets or clipboard manager with sticky (static) items

There is a clipboard manager called copyq that is in the Software Center, and it supports "pinned" items. It does the job.

Install it from the Software Center, and you are almost ready to go.

When it launches, it puts an icon in the system tray, but by default, the icon is hidden. So if you want to see it displayed:

Right-click on system tray
Select Configure System Tray
Go to the Entries tab
In the Visibility column, select Shown

If you want it to autostart, you can configure that in the copyq Preferences.

Alternatively, the default clipboard manager can be used for basic clipboard memory, and Gnome To Do (available in Software Center) can be used for long-term storage of text snippets. Gnome To Dois not designed for that purpose, but it could be used for it.


why is maximum resolution 640x480 with Nvidia?

http://www.iloveubuntu.net/easily-increase-screen-resolutions-indicator-scaleres

  If the user's screen features a 1440x900 resolution, the xrandr-based
  Indicator ScaleRes will add (as extra resolutions) 1585x991, 1800x1125
  and 1872x1170, basically, multiplying the native screen resolution by
  1.10, 1.25, 1.30

I have not had the same problems as you, though I have Lubuntu on an old machine with Nvidia as well.  I can only use the stock Ubuntu driver, because the driver that would work for my machine nvidia-96 depends on xorg-video-abi-10 which unfortunately doesn't exist... whoops.  This bug also affects YOU.  Look through this bug report for more details.

https://bugs.launchpad.net/ubuntu/+source/nvidia-graphics-drivers-173/+bug/948053


Sticky notes in Ubuntu 17.04 disappear after a shutdown

It is bug in gnome-applets, sticky notes does not create required directory if that does not exists. Try to create ~/.config/gnome-applets manually.


Tried using Katoolin without knowing what it did, Ubuntu is broken now

Since you don't have important data, the easiest way to fix the issue is to reinstall Ubuntu in the same partition you had Ubuntu installed.
When Ubuntu asks for where to install Ubuntu during partitioning (See this answer for details), choose "something else", and set the mount point of the partition where Ubuntu was installed as / (root), so that the installer will again install it there.
The installer should automatically detect the Windows 10, and it would automatically configure the dual boot.


This is not a severe problem. It simply says that the file in /etc/apt/apt.conf.d/20auto-upgrades.ucf-dist is ignored because of invalid file extension. Remove the extension and it should be all OK.

sudo mv /etc/apt/apt.conf.d/20auto-upgrades.ucf-dist /etc/apt/apt.conf.d/20auto-upgrades

is the command you'll run to rename it.

In my 16.04, the content of the file is some configuration options related to apt that control whether or not automatic package update will run and automatic cleaning of packages will occur. Here is the content of it

APT::Periodic::Update-Package-Lists "0";
APT::Periodic::Download-Upgradeable-Packages "0";
APT::Periodic::AutocleanInterval "0";
APT::Periodic::Unattended-Upgrade "0";


Installing Ubuntu touch on samsung galaxy tab 2 p3100

There is an old build (Apr-2013), but you may still need to wait a few more weeks.

The number of devices support for daily builds is in the process of being extended.

Changes to phablet-flash will shortly support additional devices and sources, rather than some complicated install procedure more suited to XDA-developers (no slight intended).

http://sergiusens.github.io/posts/updates-to-phablet-flash.html

UPDATE

Also look at: Ubuntu Touch Porting: next steps

The 'current status' for Galaxy Tab 2 7.0 (GT-P3100/P3110/P3113) can be found at:

https://wiki.ubuntu.com/Touch/Devices/p3100 (3G + WiFi)

and

https://wiki.ubuntu.com/Touch/Devices/p3110 (WiFi only)


Install xp in a different partition and then boot with live cd/usb.

Use boot-repair to reinstall grub. Enjoy :)

How to install and use boot-repair : https://help.ubuntu.com/community/Boot-Repair


SSD for Ubuntu and Which folders could I locate them on SSD

A linux installation after a few months of usage will show major disk space usage shares in /usr, /var, /lib and /opt, where /usr is the most demanding filesystem that may span 60-70% of the root filesystem. Hence to speed up your system while keeping SSD wear to minimum, place your /var, /tmp, /home and swap on a spinning disk. You can place rest of the root filesystem tree (should you choose a single / or divide it in /boot, / and /usr) on the SSD.

Another important factor would be the reason to install Linux. If you are just interested in learning the operating system and you are not planning to install a lot of applications, a 15 GB of SSD partition should suffice. Here I would recommend you to consider different Ubuntu flavors that require less disk space and provide a good desktop experience e.g. Xubuntu or Lubuntu.


well you need to reinstall the MBR of windows to boot directly into windows. Now when you got your one problem solved, the other has a quick way around. First, to reinstal the MBR, you can use any windows cd/USB and just start repairing the windows(Windows Repair mode, they call it windows RE mode). Now when you got there, open the command prompt at windows RE mode. I am sure you can open up the command prompt,if not then google for it.Now at the command prompt, start typing as illustrated:

x:\sources>bootrec /fixmbr
x:\sources>bootrec /fixboot //Well only "/fixmbr" can do the whole thing for you, this was for the worst case

Now this is how you can boot directly into windows. Now you have many utilities to install linux to USB, in windows. Now this will solve all your problems.
PS- Do not forget to make it answer(if it really helped you) for it can remove my hassle to re-answer some other person for same concern.


You installed an unsupported kernel. The driver does not build. What is the point of installing it? you could install kernel 3.19 to 14.04, or upgrade to Ubuntu 15.04.

You built mainline kernel form source. It was not a best idea for Ubuntu.
Anyway you do not have to build kernels yourself. All mainline kernels are available at Ubuntu mainline kernel PPA.

The solution is to boot with the previous kernel using grub menu.

Then Upgrade your system to Ubuntu 15.04. You will get  3.19 kernel.


Single node cluster installation permission errors

It seems like a permission issue. Try executing start-all with sudo command.


About the architecture of Virtual-Machine

There is a link between the architecture of the host and the client, but only in so far that you can't run a 64-bit virtual machine on a 32-bit host machine.

32-bit guest on 32-bit host should work
64-bit guest on 32-bit host does not work
32-bit guest on 64-bit host should work
64-bit guest on 64-bit host should work

(By 32/64-bit host I mean the host machine CPU.)

To run a 64-bit guest, VirtualBox also requires hardware-virtualisation in the CPU (and not disabled in the BIOS!).  To test for this, run kvm-ok in a terminal:

$ kvm-ok
INFO: Your CPU supports KVM extensions
INFO: /dev/kvm exists
KVM acceleration can be used

Only the first line is important here. (This tool is intended for use with kvm, but VirtualBox uses/needs the same hardware-virtualisation support.)


This will directly show you motherboard info:

sudo dmidecode -t 2

or

sudo dmidecode | more

You can also try:

lspci


Libreoffice 6.0.1.1 Writer on Ubuntu 16.04 opens then closes. Why?

PPA clearly states you will be on bleeding-edge
When you attempt to add the PPA you are warned:

In general, this PPA is not for the average user to install without
a closer look (if it would be, its packages would be in the main
repositories). OTOH, it is way better to use packages from this
PPA than using the *.deb files that The Document Foundation provides
upstream, which are intentionally build against a very old baseline
for maximum compatibility. So, if you want to be on the bleeding
edge, do it here, not with upstream *.debs.

at this point you can press Ctrl+C and the PPA will not be added.


That is not a list of directories.  That is a list of filesystems.

/tmp would only show up in this list if your /tmp was a mount point for a separate filesystem, rather than a directory.

You don't need /tmp to be a separate filesystem.  There are various reasons some people or pre-configured systems sometimes do this, but it's not mandatory and it's a choice.  In particular, some people run /tmp as a tmpfs filesystem.  The performance benefits of this are debatable, and it can have drawbacks.  Unless you have specific requirements that make having /tmp as a regular directory in your root filesystem inappropriate, my recommendation is to stick with what you have.


E: Package 'libssl1.0.0' has no installation candidate

The results of rmadison libssl1.0.0 show that the libssl1.0.0 package was dropped from the default Ubuntu repositories after Ubuntu 18.04.

$ rmadison libssl1.0.0
 libssl1.0.0 | 1.0.1-4ubuntu3     | precise          | amd64, armel, armhf, i386, powerpc
 libssl1.0.0 | 1.0.1-4ubuntu5.39  | precise-security | amd64, armel, armhf, i386, powerpc
 libssl1.0.0 | 1.0.1-4ubuntu5.39  | precise-updates  | amd64, armel, armhf, i386, powerpc
 libssl1.0.0 | 1.0.1f-1ubuntu2    | trusty           | amd64, arm64, armhf, i386, powerpc, ppc64el
 libssl1.0.0 | 1.0.1f-1ubuntu2.27 | trusty-security  | amd64, arm64, armhf, i386, powerpc, ppc64el
 libssl1.0.0 | 1.0.1f-1ubuntu2.27 | trusty-updates   | amd64, arm64, armhf, i386, powerpc, ppc64el
 libssl1.0.0 | 1.0.2g-1ubuntu4    | xenial           | amd64, arm64, armhf, i386, powerpc, ppc64el, s390x
 libssl1.0.0 | 1.0.2g-1ubuntu4.15 | xenial-security  | amd64, arm64, armhf, i386, powerpc, ppc64el, s390x
 libssl1.0.0 | 1.0.2g-1ubuntu4.15 | xenial-updates   | amd64, arm64, armhf, i386, powerpc, ppc64el, s390x
 libssl1.0.0 | 1.0.2n-1ubuntu5    | bionic           | amd64, arm64, armhf, i386, ppc64el, s390x
 libssl1.0.0 | 1.0.2n-1ubuntu5.3  | bionic-security  | amd64, arm64, armhf, i386, ppc64el, s390x
 libssl1.0.0 | 1.0.2n-1ubuntu5.3  | bionic-updates   | amd64, arm64, armhf, i386, ppc64el, s390x

The results of apt search libssl show that the libssl package has been upgraded to libssl1.1 in Ubuntu 19.04 (and later). To install it open the terminal and type:

sudo apt install libssl1.1


How do I stop Pulseaudio using huge amounts of memory?

Are you sure that this is real memory consumption and not virtual-only? According to https://www.freedesktop.org/wiki/Software/PulseAudio/Documentation/User/MemoryConsumption/, it reserves 64 MB per client on virtual memory, but that should actually be "fine" and not result in OOM situations. On my 18.04 ubuntu, top shows e.g.

%Cpu(s):  4,1 us,  1,5 sy,  0,0 ni, 93,2 id,  1,1 wa,  0,0 hi,  0,0 si,  0,0 st
KiB Mem : 16135328 total,  1088888 free,  8108764 used,  6937676 buff/cache
KiB Swap:  1003516 total,   961276 free,    42240 used.  6562996 avail Mem

  PID USER      PR  NI    VIRT    RES    SHR S  %CPU %MEM     TIME+ COMMAND
[...]
20428 delf       9 -11 2464944  13808  10264 S   4,6  0,1   3:05.72 pulseaudio

So ~2,5 gig on virtual memory, while actually %-memory consumed measured with ps shows:

% ps -o pid,%mem,command ax | grep pulseaudio
 1811  0.0 /usr/bin/pulseaudio --daemonize=no
 7363  0.0 grep pulseaudio
20428  0.0 /usr/bin/pulseaudio --start --log-target=syslog

So maybe everything is just fine..? :)


Can not update Python and other software

Be sure to update your repositories, then the system files.  Then perform a reinstall of python3.

(The $ represents the command prompt you see in the terminal screen.  The command is what follows the $ prompt.):

$ sudo apt update
$ sudo apt upgrade
$ sudo apt install python3-minimal
$ sudo apt install --reinstall python3

Then from there add some of the other packages you might need from the repository.  You can get a list of the default repository packages with:

$ apt-cache search "^python3" | less


How to set the external monitor as primary screen on my laptop while the screen on my laptop cannot display anything?

Use the Fn key + display key (often F4) on your laptop to switch active display.


Understanding sed expression to replace the last word from each line with the first one

After correcting the basic syntax mistakes, you have:

sed "s/\(^[a-z,0-9]*\)\(.*\)\([a-z,0-9]*$\)/\1\2\1/g"

s/old/new/ replace old with new
\(^[a-z,0-9]*\) save any number of lowercase letters or numbers at the start of the line (^ is start of line) for later (reference later with \1)
\(.*\) Save any number of any characters for later (to reference as \2)
\([a-z,0-9]*$\) save any number of lowercase letters or numbers at the end of the line ($ is end of line) for later (reference as \3)
\1\2\1 print the first pattern, then the second, then the first again
g this is inappropriate in this expression. It means act on multiple matches on the same line, but our expression has to read the whole line, so g makes no sense and should be omitted.

This still will not work, because regular expressions are greedy, so the middle \(.*\) matches everything after the first word, resulting in the first word being reprinted at the end of the line without replacing anything.

You could fix it (also adding I for case-insensitive search):

sed "s/\(^[a-z,0-9]*\) \(.*\) \([a-z,0-9]*$\)/\1 \2 \1/I"

If you wanted to include other characters besides letters and numbers:

sed -r 's/^([^ ]+) (.*) ([^ ]+)$/\1 \2 \1/'

-r use ERE (saves using all those backslashes)
[^ ]+ at least one of any characters except spaces


If it has failed in the past it will likely fail again in the future. Take the ram back and tell him it is faulty. He will either test the RAM or take you at your word.

The only other thing I can think of is it could be a bad power supply. Dodgy power can cause lots of weird hardware problems.


Which version of Ardour should I download?

You are using a 32 bit Ubuntu version so you need to download "Ardour 4.2 for Linux x86".

"Ardour 4.2 source code for all platforms" is aimed at developers, it is just plain source code which need to be compiled to be run. It is not for end user.


iBus (Anthy) not working with Skype 4.1.0.20

I just found the solution for this!

/usr/bin/ibus-daemon must be started with -x option.

I've added 'iBus' to startup applications with following command:

/usr/bin/ibus-daemon -x -d

I also have following lines in my /etc/environment but I'm not sure if they affect the result somehow (don't really want to experiment now):

LANG="en_US.UTF-8"
LC_ALL="en_US.UTF-8"
GTK_IM_MODULE=ibus
XMODIFIERS=@im=ibus
QT_IM_MODULE=ibus

Update: variables mentioned above has no any effect really in case of skype

Update 2: on Fresh installation of Ubuntu 12.10 I just installed ibus-qt4 (not ibus!) and selected iBus as IME. It works without any additional tricks


How to orbit in Blender without a MMB these days?

Unity Tweak Tool setting screenshot
Thanks to the Unity Tweak Tool, you can disable the Super key from bringing up the HUD shortcuts when hold down.
Once that's done, in the Blender Prefs, under Input/3D view/3D View (Global)/Rotate View, set it to use Super + LMB.
Note that the Super key shows as "Cmd" in Blender.

Similarly do this to select loops in Edit mode:
Blender Prefs setup for "select loops" screenshot


Unable to set up new KVM Ubuntu 14.04 server

Ok, so I JUST NOTICED, that I am a complete MORON for the first portion of the issue....

mnt/Storage/Virtual_Machines was the directory which had the VM's running off of the Raidz2 array, 6x 4TB HDD's 5400 rpm. I added a 128 Gig SSD for this specific VM because it is for a game that reads and writes alot, so I moved the VM over to the SSD. I left the old one there as a backup, and apparently forgot to go in and move it.

Didn't notice the difference in the command I copied and pasted, as it was the difference of

/mnt/Storage/Virtual_Machines/VG-MineCraftServer/
/mnt/Virtual_Machines/VG-MineCraftServer/

SO, that leaves me with the issue of the sudoers file, but I will mark this as solved, as I have another question SPECIFICALLY on the sudoers issue...


Add "delete confirmation prompt" in Thunar

You can put whatever you want for the name and description, but here's the command part:

zenity --question --text="Are you sure you want to delete %F?" && rm -rf %F

It shows a dialog asking the user whether they want to delete the file(s) and if so, it deletes it. Also, if you just wanted to move the files to the trash, since Thunar already asks when you use Shift+Delete, then use this:

zenity --question --text="Are you sure you want to move %F to the trash?" && gvfs-trash %F

Lastly, be sure to click on the "Appearance Conditions" tab and check all the file types so that the action won't just appear on text files

To enable the keyboard shortcut for this action, proceed as explained here. Basically, in the file ~/.config/Thunar/accels.scm, edit the corresponding custom action, so that it looks like this:

(gtk_accel_path "<Actions>/ThunarActions/uca-action-1484038296058938-2" "Delete")


How to turn off or delete the default lubuntu panel in 14.04?

Use the Preferences - Default applications for LXSession menu option...

Then as part of the core-applications tab - just remove the "lxpanel" text as shown.  This will stop the lxpanel application from running leaving you with Cairo.  To reverse - simply add "lxpanel" back into this text field.


The correct driver - supposedly - is already in the repositories. No need to install that old script from Realtek (but it failed anyway so no harm done).

In Terminal,

sudo apt update
sudo apt install rtl8812au-dkms

Reboot.


Is there a way to equalize (i.e. drop the bass of) videos?

If you use VLC, go to Tools > Effects and Filters

This will bring up a graphic equaliser.


Compaq Presario B1900 can't detect USB devices

You can give a try to this:

Install dconf-editor

sudo apt-get install dconf-tools

When installed open it using following command and follow mentioned path:

dconf-editor

Path: org->gnome->desktop->media-handling and check automount and automount-open
Sometime it detects but doesn't mount, so execute following command and see what happens:

sudo mount -a

sudo mount displays all the media that is mounted in your system..
If it does not work then try to open your system in another shell like gnome-classic or gnome-class(no effects) from login screen and check what happens.

Hope it somewhat helps you!!

Source : help.ubuntu.com


How to take screenshot of a Gnome application without the transparent CSD border?

Disabling Xfce's compositor fixes the problem.


How can I mount partitions in Thunar without password?

You could edit the file org.freedesktop.udisks2.policy in /usr/share/polkit-1/actions.
Search for the textblock containing the line:
<action id="org.freedesktop.udisks2.filesystem-mount-system">
At the bottom of this block you will find the line:
<allow_active>auth_admin_keep</allow_active>
Change auth_admin_keep to yes and you will be able to mout partitions without being asked for a password. However any user wil be able to perform this action.

The .rules files will not work since the polkit version installed in 18.04 is 0.105, .rules files can only be used in version 0.106 and higher. I don't know why your solution isn't working, it seems to be conforming to polkit rules. See the following answer as well: PolicyKit rules never come into effect .


How to change language in Ubuntu Gnome's lock screen?

There are currently some issues with using Ubuntu's default display manager LightDM together with GNOME shell. So switching from LightDM to GNOME's GDM might help.


Can I install Ubuntu Linux onto the hard drive of my Lenovo G570 laptop?

This answer is focused on the G570, but it is likely to apply to other laptops in this group.

It is possible to install Ubuntu onto your laptop, but it is likely to permanently remove your ability to run Windows on the G570.

The G570 comes with Windows 7 installed. It is conspicuously absent from the list of Lenovo laptops that can run Windows 10.

Multiple users report that the G570 does not have suitable drivers for updated releases of Windows 10.

Lenovo did initially support Windows 8 on the G570, but the G570 is explicitly not supported for Windows 8.1. Windows '8.0' has not been supported by Microsoft since 2016, so that is not an option either.

Since security support for consumer Windows 7 ends in January 2020, owners need an alternative OS. Unfortunately, installing Ubuntu (or other Linux distros) onto the G570 is also tricky.

A minor problem is that the battery management software is Lenovo Enhanced Experience 2.0, which is only available for Windows. As a result, you must select 'Maximum battery life' in Lenovo's Energy Management application before installing Linux, or your laptop will be stuck forever in 'Optimized battery health' mode, which targets a battery level of 50%.

The more serious problem is that the G570 was not supplied with Windows 7 installation disks. If you try to download an ISO file from Microsoft with a G570 product key, they will refuse and direct you to your OEM. Lenovo also do not supply installation disks for the G570. Because of its IBM heritage, the G570 instead comes with a product called OneKey Recovery 7.0 (OKR), which enables you to re-install or repair Windows 7 from a hidden partition called "LENOVO_PART" on the original hard drive. OKR is launched from a special button on the G570, which is controlled by a custom boot partition. In addition, OKR stores hidden files and backups on a logical partition called "LENOVO" (which Linux and Windows otherwise regard as a completely normal partition for data storage).

If you wish to completely and irrevocably replace Windows 7 with Ubuntu, this is not a problem. But if you want to be able to use Windows software again, now or in the future, it is therefore critically important that your installation does not touch either the hidden OKR partition or the custom boot partition and does not delete the "LENOVO" logical partition. Deleting any of these partitions will prevent Windows from booting. Attempting to backup the hidden partition in its default state will also prevent Windows from booting. If Linux does alter anything, then you may be able to repair it using a retail Windows 7 installation (not System Repair) DVD, but Microsoft no longer sells these, and you must use an SP1 DVD.

To deal with the case of complete hard drive failure, it is possible to use the OKR software to create bootable System Restore DVDs. If the partition boundaries have been altered, these DVDs cannot just re-create the hidden partition. But they are able to completely wipe the hard drive and recreate the original factory installation, including both Windows and OKR. But if either DVD is damaged, then you will not be able to restore your Windows 7.

More positively, user asanchez1987 on the CentOS forum reports  that they were able to install CentOS onto a G570, without damaging either Windows or OKR. They first shrank the Windows primary partition (C: or /sda2) by 100GB. This left a gap in the middle of the drive:

They then moved the start of the extended partition earlier in the disk using gparted (on a live CD). They then used CentOS' installation procedure to insert the boot partition at the start of the extended partition. They used something called an "LVM Physical Volume" to create the CentOS system and swap partitions. I suspect, but cannot prove, that this scheme was successful because it not only left the hidden partitions and files intact, but also preserved them at exactly the same bytes on the hard drive. Unfortunately, it is probably not possible to exactly replicate this method with Ubuntu, because the Ubuntu installer insists on placing Grub in the MBR. In fact, it is puzzling how CentOS was able to this without altering the MBR. It may be noteworthy that asanchez1987 never explicitly stated that they were still able to boot Windows after installing Linux.

BTW if you follow some of the links above, you will see discussion about adding the OKR partitions and files to a system that already has Linux/Windows. These netizens are talking about the OKR Engineering 7.0 DVD for Lenovo staff, which is different from the OKR System Restore DVDs. In the past, Lenovo seemed fairly relaxed about users pirating it, but 7.0 no longer seems to be available from anything resembling a trustworthy source.

BTW, my Lenovo G570 does not use UEFI. Some people have UEFI on its 2013 grandchild (the G580) but this can be damaged by an Ubuntu installation.


Ubuntu printing trouble over the network

If it is not already done, install Smb4K on your computer. It can greatly help with remote printers. I could not reach my printer until I did that.


/boot directory is out space for new software updates

run sudo dpkg --list 'linux-image*' | grep ^ii to see all the kernels you have installed.

run uname -r to see your currently running kernel.  Do not remove this kernel (linux-image)

use apt-get purge to remove the other images you don't need anymore, e.g., if you are using 3.13.0-34, remove the others:

sudo apt-get purge linux-image-3.13.0-32-generic linux-image-3.13.0-33-generic


I assume you entered the URL correctly (no https but http, and only the v=... part, like http://www.youtube.com/watch?v=-wxawmjnRWY)?

Open the Extras menu and click on Messages. Now click play again and see what message's there.

My guess is it's

lua error: Couldn't extract youtube video URL, please check for updates to this script

VLC parses YouTube's HTML source code to look for the video, but sometimes, YouTube changes its way it outputs the HTML, so VLC is unable to find the video URL.

Possible workarounds

Go to https://www.youtube.com/html5 and enable html5 there to play the video in your browser without flash
Install minitube and try to play the video there
Wait for an update of VLC (or update the lua script yourself - not so easy, see Updating the VLC YouTube parser)
Install the package youtube-dl and download the video to your harddisk. It's a command line utility though

Updating the VLC YouTube parser

Update just the Lua script for YouTube parsing to the latest version from VLC:

Open the Terminal application and enter these commands:

Make sure curl is installed, we need this to download the new file

sudo apt-get install curl

Get rid of the old, non-working scripts

sudo rm /usr/lib/vlc/lua/playlist/youtube.*

Download the current ones (use the whole command line, yes, it's quite long):

sudo curl "http://git.videolan.org/?p=vlc.git;a=blob_plain;f=share/lua/playlist/youtube.lua;hb=HEAD" -o /usr/lib/vlc/lua/playlist/youtube.lua

See if it works.


Ctrl + V will not work if I close the application I copied text from

Because the text is not actually "copied" anywhere. The copying application notifies the X server that it has the CLIPBOARD selection. The pasting application asks the X server which application has the CLIPBOARD selection, and then communicates with the application to negotiate content transfer. This obviously fails if the copying application has been closed.


It turns out the shortcut I had previously been trying to add via System Settings/Keyboard/Shortcuts/Custom Shortcuts was still there and was the cause of the problem.
I had been trying to assign the period "." to the "," key on the German numeric keypad on my keyboard. I added the shortcut via the GUI and I'm not sure how it got mixed up. The '8' key did not seem to be assigned to it.
When I tried xmodmap -pke | grep 8, the key seemed to be assigned correctly. Also, resetting the keyboard with setxkbmap -layout de had no effect.
However, when I deleted the shortcut the 8 key went back to behaving normally.


There is no setting to not display the border around the dash, when the dash is not full screen. The only way to make the border not be visible, is to maximize the dash by clicking the maximize button in the top panel, while the dash is open.


Kubuntu 20.04 plasma desktop does not start after login

Even I have a fresh install of Kubuntu 20.04 (Ryzen 3550h + GTX1050 3GB).
The hack the works for me is
sudo killall sddm
on console pressing CTRL+ALT+F2.
No problem booting from power source but only appears while booting on battery .
The problem first started appearing when I uninstalled proprietary Nvidia Drivers (440). And maybe to retain your animations, using compositor as XRender helps.


I found the answer myself. The solution was to increase the variable gap_y to a value higher than 29.


Can Gedit or Gvim copy multiple seperate lines to the clipboard (maybe by using bookmarks, or a script or another editor)

Neither gedit nor gvim have that capability.


Is there any way in Ubuntu 17.10 to disable touchpad gestures with Xorg?

Ubuntu 17.10 uses Wayland
From the libinput wiki page:

libinput is a library to handle input devices in Wayland compositors and to provide a generic X.Org input driver. It provides
device detection, device handling, input device event processing and
abstraction so minimize the amount of custom input code compositors
need to provide the common set of functionality that users expect.

libinput and synaptics can be both be installed
If you have libinput and synaptics installed in parallel with default configuration (i.e. no files in /etc/X11/xorg.conf.d for either), synaptics will take precedence due to its higher numeric order 70- in the default installation directory. To avoid this, you can symlink the default libinput configuration (40-libinput.conf) to /etc/X11/xorg.conf.d/ where directory search order precedence over 70-synaptics.conf will take place instead:
$ sudo ln -s /usr/share/X11/xorg.conf.d/40-libinput.conf /etc/X11/xorg.conf.d/40-libinput.conf

If you do have /etc/X11/xorg.conf.d/ configuration files for both, the libinput file must be ordered second. If you want to disable libinput (and fallback to older drivers) - just remove the previously created symbolic link from /etc/X11/xorg.conf.d/.
Check what libinput is managing
One way to check which devices are managed by libinput is the xorg logfile. For example, the following:
$ grep -e "Using input driver 'libinput'" /path/to/Xorg.0.log

[    28.799] (II) Using input driver 'libinput' for 'Power Button'
[    28.847] (II) Using input driver 'libinput' for 'Video Bus'
[    28.853] (II) Using input driver 'libinput' for 'Power Button'
[    28.860] (II) Using input driver 'libinput' for 'Sleep Button'
[    28.872] (II) Using input driver 'libinput' for 'AT Translated Set 2 keyboard'
[    28.878] (II) Using input driver 'libinput' for 'SynPS/2 Synaptics TouchPad'
[    28.886] (II) Using input driver 'libinput' for 'TPPS/2 IBM TrackPoint'
[    28.895] (II) Using input driver 'libinput' for 'ThinkPad Extra Buttons'

is a notebook without any configuration files in /etc/X11/xorg.conf.d/, i.e. devices are autodetected.
Choose synaptics driver over lipinput for one device
Of course you can elect to use an alternative driver for one device and libinput for others. A number of factors may influence which driver to use. For example, in comparison to Touchpad Synaptics the libinput driver has fewer options to customize touchpad behaviour to one's own taste, but far more programmatic logic to process multitouch events (e.g. palm detection as well). Hence, it makes sense to try the alternative, if you are experiencing problems on your hardware with one driver or the other.
Reference
Answer from ArchLinux Wiki which has many more details.


How I can change the color of a themed box?

You can change the theme property values by editing the nautilus.css file. This file may be located here:

/usr/share/themes/$YOUR_THEME/gtk-3.0/apps/nautilus.css

Replace $YOUR_THEME with the name of your theme. The file requires root privileges to be edited. You can edit the file by copying and pasting the following command in a Terminal and then entering your password:

sudo gedit /usr/share/themes/$YOUR_THEME/gtk-3.0/apps/nautilus.css

Once again replace $YOUR_THEME with the name of your theme.

When you've successfully opened the file you may now look for the following lines of code. If you opened the file using Gedit you can search using CTRL+F.

...
NautilusWindow .sidebar,
NautilusWindow .sidebar .view {
...

This may look a bit different, maybe only one of the two lines are specified or maybe more have been added, so be patient and look carefully for something similar to the lines above.

You may now look below this code for a line with the following code:

...
background-color: $VALUE;
...

$VALUE can be any color value and is the background color of your right side menu. You can replace the value by any valid hexadecimal color code or rgb code (among other ways). Examples:

background-color: #00ff00; //Green background
background-color: rgb (255, 255, 0); //Blue background

I hope this helps.


Most software can be uninstalled via the softwarecenter: just serch for ubuntu one select the program you want to uninstall and click remove.

For more control, but also more possibilities to damage or crash your system you can install synaptic package manager.


Splash

I think that you are trying to change the KDE splash background.

The Kubuntu 12.04 splashes: Grub "splash" -> Plymouth -> Login Screen (KDM theme) > KDE splash (KSplashX/KSplashQML)

KSplashX

The KSplashX REDAME is explaining the splash syntax: https://projects.kde.org/projects/kde/kde-workspace/repository/revisions/master/entry/ksplash/ksplashx/README

The default KSplash themes are: /usr/share/kde4/apps/ksplash/Themes/.

If you download and install new themes through the "Get New Themes, KDE system Settings > Workspace Appearance > Splash Screen, they are installed to the ~/.kde/share/apps/ksplash/Themes/.

KSplashQML

The KSplashQML is a new and shiny:

http://aseigo.blogspot.fi/2011/11/plasma-workspaces-48.html:

  Right now, we do not have documentation on Techbase for this new
  addition but if one looks in kde-workspace/ksplash/ksplashqml/themes
  it becomes very apparent.

More: http://www.kubuntuforums.net/showthread.php?56645-KSplashQML-Themes

Note

The KDE is caching things to the /var/tmp/kdecache-$USER/. Sometimes the KDE is using the cached picture instead of the changed splash backgrounds. The cached data can be removed: http://forum.kde.org/viewtopic.php?f=17&t=45909 .


gdlib-config Ubuntu 16.04 / Ubuntu 18.04

On Ubuntu 18.04, with GD-2.56, drop the obsolete check warning by the option --ignore_missing_gd would work after installing the libgd libraries with apt.

i.e.

sudo apt install libgd-dev libgd-perl
perl Makefile.PL --ignore_missing_gd


Weird pixelated white border. Ubuntu Xenial (16.04)

The culprit is the new version of the NVidia driver. Reverting to 375 doesn't work because IMHO it has also been updated (minor version) and/or its dependencies are a mix of several versions. Anyway:

Remove the PPA. On my computer I deleted the file /etc/apt/sources.list.d/graphics-drivers-ubuntu-ppa-xenial.list pointing to the repository deb http://ppa.launchpad.net/graphics-drivers/ppa/ubuntu xenial main
Remove all the installed NVidia packages, i.e. nvidia-*. On my computer I deleted several packages with apt remove nvidia-361 nvidia-375 nvidia-378
Update the packages list with apt update
Install the last official version (i.e. 367) with apt install nvidia-367

As a side note, I'm always amazed how updates regularly break Ubuntu...


How do I group/un-group parent/child windows?

The only known location for that sort of option is:

/apps/gnome/interface


To rename a file, open Files and go to the folder the files are at. Then, left click on the file, and select Rename...


You need to add a new entry for blc in  evdev.xml and evdev.lst files from /usr/share/X11/xkb/rules directory.

  Adding a new layout requires that you also add the file to rules/evdev.xml. If you use other X11 wms you may want to give your layout to the rest of the xorg system. You can do this by adding the file to the symbols directory, and adding a line for the file in rules/evdev.lst under the ! layout section.

Source: Howto: Custom keyboard layout definitions


New Dell Vostro 3550 will not boot into Live CD

I've gotten Ubuntu 10.10 running on a new Vostro 3550, but there are still a few issues: e.g. I get sound from the headphone jack, but not the speakers.

To get 10.10 installed, I used a live image on a USB stick (thumb drive).

Strangely, the installation worked when I inserted the USB stick into the eSATA/USB port, but not when I inserted it into the USB port on the right side of the computer.  (That port has a strange symbol indicating that it is no ordinary USB port, but I'm not sure what it means)


USB space reduced after making it bootable and unable to recover

The startup disk creator is buggy and has been more or less dropped in 16.04 and replaced with a more simple interface (of the same name).

I would not bother trying to fix it.  Just try to reformat it.  The best thing to do is to pinch your nose and find a windows machine because you tried to do what you could in Linux.  Stick it in and see what it will do, then reformat it the slow way.

Before doing that.  You might try deleting the partition table and then making another one in gparted.  Then try to add a partition and format it.
The tools called disks (in lubuntu 16.04) is better and can slow format too.

When making a new startup disk.  Best to format your disk before and and NOT use startup disk creator to do that (you know that now and that is how I know it too).  There are a few tools to make a startup disk on Ubuntu.  Unetbootin is one.  While you are on a Windows machine, I recommend Live Linux Installer, or Universal USB Creator.


Is it safe to hot swap batteries of different capacities?

The command xfce4-power-manager --restart will restart the running power manager instance.  You may also use the command xfce4-power-manager --no-daemon which may be useful in debugging to possibly determine if/why power manager is picking up erroneous values.

xfce4-power-manager gets support for devices from the upowerd daemon.

In order to pick up changes to reported device IDs and capacity, you may need to also restart that service. This can be done with the command sudo systemctl restart upower.

To see the device details directly from upower, use the command upower -d.

Your output will be something like this:

  native-path:          BAT0
  vendor:               LGC
  model:                42T4969
  serial:               805
  power supply:         yes
  updated:              Thu 02 Jan 2020 04:06:00 PM PST (56 seconds ago)
  has history:          yes
  has statistics:       yes
  battery
    present:             yes
    rechargeable:        yes
    state:               fully-charged
    warning-level:       none
    energy:              72.9825 Wh
    energy-empty:        0 Wh
    energy-full:         73.926 Wh
    energy-full-design:  93.5952 Wh
    energy-rate:         0 W
    voltage:             12.627 V
    percentage:          98%
    capacity:            78.9848%
    technology:          lithium-ion
    icon-name:          'battery-full-charged-symbolic'


No, unfortunately not. And yes, xkb-data is updated once in a while.

One thing you can do to make it less inconvenient is to put your custom variant in a separate file instead of editing the us file. Then, when xkb-data gets updated, you only need to redo evdev.xml/base.xml.


Migration from generic OpenStack to Ubuntu Openstack

Unfortunately there's no real simple way of doing this once you're up and running without starting over.

We should perhaps in the future we could do something like migrating VMs from one cloud to another but we're not anywhere close to that, sorry.


Installing php7.4-memcached and php7.4-apcu but getting php-memached and php-apcu

That's normal - the php packages refer behind the scenes to the version-specific packages and you should be installing the unversioned PHP packages anyways.  Those aren't likely to change from the PHP version on the system, especially since it's an LTS release you're using.  There's no chance a 'new' PHP version will land in Focal right now.
This is Expected Behavior.  Trust me though that it will install memcached from PHP 7.4 (or a 7.4-compatible memcached anyways).  Not all PHP packages originate from the PHP source code and some are compiled separately (and have separate source packages) so they have to use the unversioned php package name syntax for installing.


games and rendered surfaces get slow after having computer on for some time

Your computer is processing too many things at once and the things that you are processing may take up a lot of memory which slows down the computer, plus you may be running more than one program.

The way you can fix this is by turning off the effects that comes as the default, or you can buy more memory for your computer, or run one thing at a time, which I think is going to be a problem for you because you want to run more than one program at a time.

So just get some more memory or turn off the effects in desktop preferences then click on effects and then click none effects, because it works like magic without the full effects on.


shred is well suited to the task. Personally I would actually want to WRITE to the blocks rather than wrap the whole thing in encryption. Example,

https://serverfault.com/questions/6440/is-there-an-alternative-to-dev-urandom

Zap the disk with the openssl random data generator and then shred it. If you're really that concerned with the data that might be left on the disk then you should remove it and physically destroy. It's the only way to be sure as it's 100% under your control.


How to fix Samba read and write permissions for directories in an ext4 partition?

edit your samba conf file(mostly /etc/samba/smb.conf and add the lines below:

follow symlinks = yes
wide symlinks = yes
unix extensions = no

Restart samba .

For more info visit this thread in Ubuntu forums:
http://ubuntuforums.org/showthread.php?t=352016


you can install Sqlectron_1.30.0_amd64.deb from the link below.
https://github.com/sqlectron/sqlectron-gui/releases

Move to the directory you installed, and run sudo gdebi Sqlectron_1.30.0_amd64.deb to complete the installation.

Good Luck!!


I have something similar when I try running update / upgrade:

sudo apt-get update
E: Driver for method /usr/lib/apt/methods/https could not be found

But my /etc/apt/sources.list file does not have any https in it...

Here's the answer to my problem.


If you tried the first answer here Lubuntu Taskbar missing and got the error message, I think it is due to a missing or unselected component. Please run

sudo apt-get install at-spi2-core

and see if the error is gone. Also if you killed the  lxpanelctl process restart it with  lxpanelctl restart and
openbox --restart.
Restart or login as a guest user to see if the panels show.


Websites can't seem to access Flash Local Storage

Try changing the preferences using flash-player-properties.
1. Open Adobe Flash Player preferences (either by searching in dash or by running flash-player-properties).
2. Go to Storage and select allow sites to store information on this computer.
3. You can also modify Local Storage Settings by Site.


Can't open desktop folders in Ubuntu 18.04

The solution I found here by @Aashutosh Taikar worked for me in ubuntu 18.10:

sudo rm -f /usr/share/dbus-1/services/org.mate.freedesktop.FileManager1.service

After restarting my PC I was once more able to open desktop folders and the Rubbish Bin by double-clicking on their icons.

Before doing this nothing would happen when I clicked on them, and I'd just see error messages like this in my /var/log/syslog:

nautilus-deskto[1854]: cannot open folder on desktop, freedesktop bus not ready


The problem was that I had few two versions of PyQt5 and sip installed for Python3. One was in /usr/lib/python3/dist-packages/ and the other in ~/.local/lib/python3.6/site-pacages/. Completely deleting .local versions helped.

That, and installing everything that I could find with gstreamer.


Use cat with output redirection. Syntax: cat file [file] [[file] ...] > joined-file.

Example with just two files (you can have many more):

$ echo "some text in a file" > file1
$ echo "another file with some text" > file2
$ cat file1 file2 > mergedfiles
$ cat mergedfiles
some text in a file
another file with some text

In case you have "many documents", make use of shell globbing (patterns):

cat input-files-dir/* > joined-file

This will join all files in that directory to the current directory (preventing it to match the output file itself). It is totally independent to the use of cat and output redirection - it's just Bash providing all the files as arguments to cat.

File types

It will just glue (join) files together as you would do with paper and tape. It does not care about the actual file format being capable of handling this. It will work for text files, but not for PDFs, ODTs, etc. Well, it will glue them together, but it's not a valid PDF/ODT anymore.

Order of joining

As phoibos pointed out the shell globbing will result in alphabetical order of file names. This is how Bash and shell globbing works.

Addendum about input file is output file error

When the pattern of the input files matches the very same file as being output, this will cause an error. It's a safety feature. Example: cat *.txt > out.txt run the second time will cause this.

What you can do about it:

Choose a more specific pattern to match the actual input files, not matching the output name. Example: input files pattern *.txt with output file output.out will not collide.
Work in different directories. In the example above I've used a separate input-files-dir directory to place all files in, and output to the current working directory. This makes it impossible to get this error.


For apache2, mysql, php you can install the lamp stack by doing

sudo apt-get install tasksel
tasksel

and choose to install LAMP server. This will create a working webserver with mysql and php pre-configured. You need to create your own database and tables to be used on the webserver in mysql though so installing MySQL Workbench might be useful too.

Javascript does not need packages since it is part of your browser.

jQuery is a javascript tool set. You download it and put the scripts in a directory inside your webserver. Something like /var/www/{project/}js/. You then include the jQuery files in your html.

It might also be useful to install a code editor. I am using Aptana myself but here is a long list: What developer text editors are available for Ubuntu?


What is the difference between a package and a software in ubuntu?

If you are familiar with MS-Windows, the usual mean of installing a software under that system is the setup.exe. As you've seen, Ubuntu uses packages.

The main (HUGE) difference is that packages have what is called dependencies so a system such as APT can go out and download all the necessary dependencies before installing the package you selected. Of course at times all dependencies were already satisfied, so just that one package gets installed.

A setup.exe and a package is an agglomeration of files within a single binary file. In most cases this is a compressed archive of some sort. Under MS-Windows, they generally use zip. Debian / Ubuntu packages use ar and tar (ar as a wrapper, tar to save all the files of the package.)

So... according to the general definition of software, one package can often be viewed as a software. The fact that it needs dependencies that automatically get installed is an artifact. However, some packages are not software per se. That is, a -doc package is probably just HTML or man files.

As a programmer, I would say that the software is the file that gets installed under /usr/bin (or an equivalent). These files are the actual brain of the software, the compiled program that is sent to the CPU in your computer to do stuff.


How do I start developing applications for Ubuntu on mobile devices?

You'll get all the information you need on the Cordova Overview page, including a full tutorial. PhoneGap or other development platforms other than Ubuntu are not supported at this point.


Ubuntu Live USB won't boot on mid 2009 Macbook Pro

The official way to startup a mac from USB stick is to press the c key as soon as you hear the startup sound... and, until the Apple logo appears.

The 'Option' key is generally used to list alternate MacOS startup disks.

Optionally, and in the event your USB boot is not detected, you can try the x key. But, that is generally used to force startup from the main MacOS disk.

Also, you may want to clear your NVRAM before installing Ubuntu to force the system to rebuild its settings.

Also, make sure you have already prepared a USB stick with rEFInd to install after Ubuntu install has completed. (Or you will not be able to select Ubuntu at boot time).

The publisher of rEFInd is a member of this exchange, and generally picks up help requests quickly.


I ended up uninstalling chrome which seemed to be fine but not sure it was needed in the end.
I think the issue is actually chrome misreporting a version problem. I downloaded and installed chrome and then went to help -> about chrome and updated the minor version there. The red flag then disappeared after that.


Attempt to read or write outside of disk 'hd0'

I got the same error and "fixed" it by reinstalling ubuntu with the LVM option.


Stuck on blue screen while booting the system

I fixed this by rebooting. At the login screen, I switched to a terminal ctrl+alt+F1 and then running sudo apt-get upgrade. That would not run, but I was told to use sudo dpkg --configure -a. After I ran sudo dpkg --configure -a, then I ran sudo apt-get upgrade. Lastly, I ran reboot. This solved the problem.


having trouble with the reinstall of windows

You need to install Windows prior to installing Ubuntu.
Take backup to ext. hdd and delete all partitions.
Install windows leave Some Unallocated space for UBUNTU.
after successful installation of windows, install ubuntu.


How can I make Alt+LeftClick work the same as a right click?

There is Shift+F10 which is the same like a simple Rightclick.

So you can do a binding on Alt+Left mouse for this combination.

How you can do such binding can be found in this nice topic:
How can I change what keys on my keyboard do? (How can I create custom keyboard commands/shortcuts?)


Ubuntu 16.04 LTS fresh installation does not detect Ethernet adapter

We have run into a similar issue on Ubuntu 14.04. Essentially, DHCP requests are coming across with a bogus MAC address when it PXE boots. Our testing has confirmed that the issue is with the E1000/E1000E (PCI/PCIe) driver. We were able to confirm this by using an older Kernel from the 2.6 tree. This article from 2008 explains the history of the driver. Currently the kernel has the E1000E driver compiled in and there is blacklisting in the E1000 that prevents it from loading for this chipset (and others). In short, the kernel is compiled so that it forces the E1000E driver to load for the Intel 82566DM-2 and it does not work (sometimes?). Our situation is more complex. But, for your case, I believe the easiest solution would be to compile your kernel with E1000 support only. Do not include E1000E support and you should (theoretically) be okay.


If you have installed mySQL from Ubuntu repository, the authentication of root user is not possible as usual with mysql -u root -p.

Instead, you have to type sudo mysql and the terminal will prompt you with your sudo password.

That should solve your problem and allow you to connect mySQL.

I had the same issue recently and I preferred getting back usual mysql -u root -p method (also easier to configure some tools e.g. mySQL Workbench, DBeaver...). Here are the steps I followed to get this done:

Connect to mySQL

sudo mysql

Create an admin account

CREATE USER 'admin'@'localhost' IDENTIFIED BY 'admin';
GRANT ALL PRIVILEGES ON *.* TO 'admin'@'localhost' WITH GRANT OPTION;

You can stop here and use the admin user instead of root. They basically have the same access rights.

If you prefer to come back to root user, you can follow the steps below:
Quit root connection and reconnect with new admin account:

quit; /* mySQL will tell you "Bye" */
mysql -u admin -p

Remove root user

drop user root@localhost;

Re-create root user with usual authentication method

CREATE USER 'root'@'localhost' IDENTIFIED BY 'the_password_you_wish_here';
GRANT ALL PRIVILEGES ON *.* TO 'root'@'localhost' WITH GRANT OPTION;

Then disconnect, re-connect with root and delete the admin account

quit; /* mySQL will tell you "Bye" */
mysql -u root -p
drop user admin@localhost;

Now you'll be able to connect with mysql -u root -p


Reinstalling Ubuntu 16.04 system doesn't show my sound card (I hear No Sound at all)

I solved it making a fresh install of Ubuntu.

At the beginning I had chosen Reinstall Ubuntu to preserve my files 'cause I have only one partition. Now I decided to shrink the partition creating a new one of 30Gb where I made the fresh install.

Everything is alright now with the sound.
Thanks for comments.


How do you disable Bluetooth from terminal in Ubuntu

To stop :

sudo service bluetooth stop

To start again:

sudo service bluetooth start

To restart :

sudo service bluetooth restart

To check current status:

service bluetooth status

Or you can use rfkill command:

rfkill block bluetooth


Epson SX115 All-in-One printer scanner not recognized

in the terminal paste

dpkg -i epson-inkjet-printer-epsom-inkjet-printer-Epson Stylus T13

in the        printer setting page
the printer device URI

usb://EPSON/T13%20T22E?serial=MEJZ004690%20%20%20%20%20%20%20%20

if connected to usb and local printer(T13 is my modedl no)
 this works for me


Which system folders can I mount to RAM drive safely?

Knowing that this is over a year old, I still feel the need to jump in here. For cases where I had loads of free (really never used) RAM I suffered from the same non-answers to a similar request, yet I always noticed that the systems were NOT using up all possible/available RAM. What I ended up doing was: I put as many of /etc /var /usr and /home into ramdisk as I could fit (I had about 12 GB RAM for that), and rsynced back to disk with a cron-job each of the mounted parts, so I would have a backup in case of power-failure. I also created an unload to disk before shutdown/reboot, and a return copy to RAM at boot using /etc/rc.local, so the machine would always be able to reboot and lose nothing. Rest assured that I've never even once needed the backup! And it's been running that way for 3 years on a debian server. Blazing fast IO response time by the way.
Using tmpfs for it wasn't any good, certain software seemed to not want to run from tmpfs, but would run fine from a separate ramdisk I mounted. And I did have to use special mount options for some software that doesn't like to run from ram, but they are all use-case specific.


Is there a log to shows any connections going out? - Ubuntu 12

Unfortunately not by default. You can use your firewall to create one. Assuming you are using ufw:

# ufw allow out log to any proto tcp port 22

Will log all outgoing connections to any server on tcp port 22. The location of the logfile should be /var/log/ufw.log but it might log it to /var/log/kern.log or /var/log/syslog depending on rsyslog's configuration.


Will the latest Ubuntu fit on a 700 MB CD?

The installation CD's for the latest stable release (12.04) will fit on a 700 MB CD-ROM. The daily images for the test version 12.10 might be larger.

As for 32bit vs 64bit. You can use both Ubuntu versions, in general there will be no huge disadvantage (and maybe even an advantage) to use the 32b version. Read more here.


exFAT, like FAT and NTFS, are native Windows disk formats and so are not aligned with Linux permission system. They don't receive flags for Owner like a EXT3 or 4, so you can't "chown" a file system with exFAT, FAT or NTFS.


I couldn't find exactly a solution for this problem, but if someone with the same issues comes to this post in the future, I'm adding here what worked for me.

I had to install Ubuntu 14.04 (which has these very same issues) and followed the instructions given by the user jackie in this question, only changing the driver name (from rtl8188ee to rtl8821ae).

My machine on Ubuntu now can use around 3/5 to 4/5 of the capacity of my internet and my network does not freeze anymore. Thats enough for me.


zero length variable added to for iteration not working

Always quote your variable expansions1:
if [ -z "$c" ]; then echo "zero length"; fi

echo "second print : "

for i in "$a" "$b" "$c"; do

if [ -z "$i" ]; then echo "zero length"

fi

done

When $c is empty, then $a $b $c is a list of only two items, and so only two iterations are performed. You can see this by running with set -x. In your original version:
second print :
++ for i in $a $b $c
++ '[' -z 1 ']'
++ for i in $a $b $c
++ '[' -z 2 ']'

whereas with the properly quoted version:
second print :
++ for i in "$a" "$b" "$c"
++ '[' -z 1 ']'
++ for i in "$a" "$b" "$c"
++ '[' -z 2 ']'
++ for i in "$a" "$b" "$c"
++ '[' -z '' ']'
++ echo 'zero length'
zero length

There are a few exceptions - see for example When is double-quoting necessary?


Copy all files from subdirectories and subsubdirectories to main directory with modifying file names by adding prefix of all parent directories

Given

$ tree folder1
folder1
├── folder2
│   ├── folder3
│   │   ├── name1.csv
│   │   ├── name2.csv
│   │   └── name3.csv
│   ├── name1.csv
│   ├── name2.csv
│   └── name3.csv
├── name1.csv
├── name2.csv
└── name3.csv

2 directories, 9 files

then you could do something like this to replace each path separator (/) in the original with _ for example:

$ find folder1 -type f -exec bash -c '
    for f; do echo cp -n "$f" path/to/newdir/"${f//\//_}"; done
' bash {} +
cp folder1/folder2/folder3/name2.csv path/to/newdir/folder1_folder2_folder3_name2.csv
cp folder1/folder2/folder3/name3.csv path/to/newdir/folder1_folder2_folder3_name3.csv
cp folder1/folder2/folder3/name1.csv path/to/newdir/folder1_folder2_folder3_name1.csv
cp folder1/folder2/name2.csv path/to/newdir/folder1_folder2_name2.csv
cp folder1/folder2/name3.csv path/to/newdir/folder1_folder2_name3.csv
cp folder1/folder2/name1.csv path/to/newdir/folder1_folder2_name1.csv
cp folder1/name2.csv path/to/newdir/folder1_name2.csv
cp folder1/name3.csv path/to/newdir/folder1_name3.csv
cp folder1/name1.csv path/to/newdir/folder1_name1.csv

Note that this doesn't guarantee unique namings if the original file or folder names already contain the _ character (which is why I included the -n no-clobber switch - just in case). You are of course free to choose a different (or no) delimiter.

Remove the echo once you are satisfied that it is doing the right thing.


how to use of sed command to search string with "/" character in it and replace with some other string?

Your original command is alright provided you want to substitute only the first occurrence of http:// of the line with www:

$ cat file.txt
foo http:// bar http:// spam
egg http:// test http://

$ sed 's/http:\/\//www/' file.txt
foo www bar http:// spam
egg www test http://

Now, as you want to replace all occurrences of http:// with www, just add the modifier g at the end:

$ sed 's/http:\/\//www/g' file.txt
foo www bar www spam
egg www test www

If you want to set a character other than / as the delimiter, you can choose a character that has no special meaning to sed and easier to implement in the test case e.g. underscore (_)will be good choice in this case:

$ sed 's_http://_www_g' file.txt
foo www bar www spam
egg www test www

If you want to modify the original file with the changed contents, you need -i option to edit the file in place:

$ sed -i 's_http://_www_g' file.txt

If you want to take a backup of original file at the same time:

$ sed -i.bak 's_http://_www_g' file.txt

After this operation, the original file will be kept as file.txt.bak and the modified file as file.txt.


I see the same behavior as you do with OpenJDK-7.

I solved it by installing version 8 of OpenJDK. If you are using Ubuntu 14.10, then you can installing with the following command:

sudo apt-get install openjdk-8-jre

and then selecting it using update-alternatives --config java

In my case, the output of update-alternatives --config java now looks like the following:

There are 2 choices for the alternative java (providing /usr/bin/java).

  Selection    Path                                            Priority   Status
------------------------------------------------------------
  0            /usr/lib/jvm/java-7-openjdk-amd64/jre/bin/java   1071      auto mode
  1            /usr/lib/jvm/java-7-openjdk-amd64/jre/bin/java   1071      manual mode
* 2            /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java   1069      manual mode

Installation followed properly after that.

Hope this helps!


I think you're on a right track.

Could not resolve 'archive.ubuntu.com' indicates some kind of a network issue, possible a DNS failure.

Maybe let's figure the Ethernet first (wifi should work out-of-the box most of the times, but there are some problematic chipsets).

In ubuntu uses network manager and we check the settings in GUI:

Open network settings

1.1. Hit the windows key

1.2. Type settings

1.3. Go to Network at the bottom
Is the Wired indicated as connected?

Does the configuration (after clicking the gear icon) look sane?

You can put your dns settings there in the IPv4 tab.

I'm on ubuntu 18.10, but it should look similar in 18.04 except a different theme


From Your question you have already have the VIDEO_TS folders so create a TOC (table of contents) so that genisoimage can read it to create the .udf file:

dvdauthor -o /parent folder/containing/VIDEO_TS -T

Now convert your dvd to the dvd compatible filesystem:

genisoimage [-V label] -dvd-video -o output.fs  /parent folder/containing/VIDEO_TS/

tip: -dvd-video creates udf filesystem required for video playback

at this point you can go ahead and burn it to a physical dvd:

wodim -v dev=/dev/sr0  output.fs

where /dev/sr0 is the path to the dvd rom


To install all the restricted packages you are required to install ubuntu-restricted-extras.

sudo apt-get install ubuntu-restricted-extras

It will install the following packages:

flashplugin-installer
gstreamer0.10-ffmpeg
gstreamer0.10-fluendo-mp3
gstreamer0.10-pitfdll
gstreamer0.10-plugins-bad
gstreamer0.10-plugins-ugly
gstreamer0.10-plugins-bad-multiverse
gstreamer0.10-plugins-ugly-multiverse
icedtea6-plugin
libavcodec-extra-52
libmp4v2-0
ttf-mscorefonts-installer
unrar

You should be able to play mp4 videos after this. If not, install vlc and try opening the videos in it.

sudo apt-get install vlc

References: http://www.makeuseof.com/tag/ubuntu-restricted-extras-install-ubuntu-linux/


Why my Google Chrome extensions stopped working?

Finally the solution was to delete and re-install all extension. They all work fine now.


Edit in /etc/default/grub

# Stops the ubuntu purple screen
#GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

# Uncomment to disable graphical terminal (grub-pc only)
GRUB_TERMINAL=console

Then run a sudo update-grub.


I had a similar problem in Linux mint with LXDE, every time i started or rebooted my system the mouse pointer resets to the default even when i edited the Xorg.conf file with mouse acceleration options, it simply didn't work.

What worked for me was editing the file /home/yourusername/.config/lxsession/LXDE/desktop.conf

I edited the [mouse] section of the file like this:

[Mouse]
AccFactor=70
AccThreshold=1
LeftHanded=0

then i rebooted the system and it worked. Note that this is my personal setup wich is faster than the default.

My pointer had since then the velocity i want. I have to mention that AccFactor only worked with values of tens (10,20,70 etc) and the AccThreshold at 1.

I think every desktop enviroment has its own configuration file, and most of them have a gui to acces the configuration, but i don't know what happen with lxde that doesn't save the changes of the mouse pointer or they are overidden every time the system starts.

Hope this could help you.

P.S. sorry if i have mistakes in my writting, i'm still learning english.


Problems with install (live cd and alt ver. install)

You may wish to try the current LTS (Long Term Support) version of ubuntu (12.04(.1)) as it has fewer support issues and tends to be generally more stable.

If it fails on this you could try X/K/Lubuntu 12.04 although likelihood is these also wont work. Though there isn't a great deal of information to go by if it fails on "downloading packages" that may be network related, try unchecking the box which says "Download updates" on the first few pages of the installer.

You may get more out of this question by providing more info, such as all the information the installer gives you.


unity-music-daemon uses large amount of memory

I am far from an expert on the topic but given that no one with more knowledge on it has answered I will try to provide a very rough idea to you.

As far as I understand "lens" is the generic term for the search functionality of the Ubuntu Dash (Dash being the thing that appears when you click the upper-left corner in the default installation). So, you can have a Wikipeda lens for example which will allow you to search for Wikipedia related information using the Dash.

On the other hand daemons are processes that run on the background and take care of having your system running smoothly and up to date (as far as my knowledge goes).

With this two things above we can state that unity-music-daemon takes care of keeping the data-based updated and running smoothly for music related queries.


Why when copying to an external drive the progress window is not correct

I would suppose you are using Nautilus as your file manager and if so there are long-standing bugs about this. Too numinous to mention effecting Mint, Fedora, Red Hat and all the like. Ubuntu is not without this same issue.

Some suggest turning off thumbnail view helps. Others put their hopes in the "newest kernel" but this still exists.

The problem = Starts off fast, then goes slower
This is because when mounted with async it will write to the cache, when the cache is full you see the "Real" write speed.

The work around seems to be sudo cp /filetobecopied /dev/nameofdevice

another posted here says that "copying in chunks" works. Unconfirmed on my part.


Xfce4-terminal, midnight commander, show prompt in title

I think there is some corruption in your system, because I tested in an up to date test system of Ubuntu 18.04.3 LTS, where I installed xfce4 and it works to get the prompt alias path in the title for me with this version of xfce4-terminal.

I suggest that you make a USB boot drive with Xubuntu and try (boot live without installing) how it works in a 'clean system'.
I think you have added something in your system that stops this from happening, or maybe your system is upgraded from a previous version of Ubuntu.


Terminal based application for downloading torrent

You can use aria2 to download torrent.

sudo apt install aria2

Then to use it:

aria2c http://example.org/mylinux.torrent
aria2c 'magnet:?xt=urn:btih:248D0A1CD08284299DE78D5C1ED359BB46717D8C'


Blank Black Screen Part Way Through Boot After HD Replacement

There appear to have been two problems.

First, the system was booting correctly, but the splash screen was never handing the display off correctly to a TTY. (This was Server Edition, and does not have a graphical UI installed).

Second, networking was failing to come up.

The solution to the first problem was to use recovery mode to turn off the splash screen, by removing "quiet splash" from the GRUB_CMDLINE_LINUX_DEFAULT line in /etc/default/grub, as per this answer, and then grub-update and reboot.  Once I did that, I was able to see and read the kernel and boot messages.

The solution to the second problem turned out to be that (for some reason I still don't understand), Ubuntu forgot the name of my network interface.  Its device name is eno1, but when I looked in /etc/network/interfaces, I discovered that the file had been rewritten to point at eth0, an interface that does not exist in my machine. Once I changed it back to eno1 the network came right up and all was well.


Closed terminal during upgrade after it asked something – how to get back?

The only option that ever gets set in /etc/update-manager/release-upgrades is what Ubuntu releases you want to be prompted for: all releases, just LTS releases, or no prompting. So even if you don't have the chance to examine the changes, nothing would really be broken. And you can always edit the file yourself to set it how you like. Most of the file consists of comments explaining how to do this. Here's its current contents (see below for details):

# Default behavior for the release upgrader.

[DEFAULT]
# Default prompting behavior, valid options:
#
#  never  - Never check for a new release.
#  normal - Check to see if a new release is available.  If more than one new
#           release is found, the release upgrader will attempt to upgrade to
#           the release that immediately succeeds the currently-running
#           release.
#  lts    - Check to see if a new LTS release is available.  The upgrader
#           will attempt to upgrade to the first LTS release available after
#           the currently-running one.  Note that this option should not be
#           used if the currently-running release is not itself an LTS
#           release, since in that case the upgrader won't be able to
#           determine if a newer release is available.
Prompt=lts

So you're unlikely to have to worry about this. With that said, I've detailed several options below. I emphasize, however, that you can probably simply ignore this altogether and proceed with your upgrade.

If you interrupted the installation, then nothing should've been done, and running it again in the same way will usually prompt you about the same things, including newer versions of conffiles.

So I recommend doing that, unless you have a specific reason not to or you've tried it and it didn't work. I'm guessing you ran sudo do-release-upgrade. That should be safe to run again.

However, you could also run

sudo apt-get --reinstall install ubuntu-release-upgrader-core

since that's the package that provides that particular file. (Don't use the --purge flag, since that would typically delete the current conffile.) Then proceed to run sudo do-release-upgrade.

If the old file has been kept -- or has already been replaced with the new file -- but the upgrade succeeds, then you shouldn't have anything to worry about.

You can also examine the new file yourself and compare it to the one you currently have. That's the file for the 14.04 version, since you're currently running 14.04, and this is a package that gets installed before the upgrade to 16.04 is carried out.


Problem to use sieve and dovcot to move spam mail to Junk folder

It looks like adding

  mailbox_command = /usr/lib/dovecot/deliver

to

  /etc/postfix/main.cf

and

  dovecot   unix  -       n       n       -       -       pipe
  flags=DRhu user=vmail:vmail argv=/usr/lib/dovecot/dovecot-lda -f >
  ${sender} -d ${recipient}

to

  master.cf

solved the problem


Players need to have MPRIS support and register themselves on the sound menu as described on the sound menu specification to place their controls in it. Currently Rhythmbox, Amarok and Banshee (via the plugin shipped in the banshee-extension-soundmenu package in Maverick) work in Maverick, Xnoise and mpd have plugins / versions you can install externally, and work is underway to add support in Exaile and Quod Libet.


Ubuntu 16.04 - Laptop with two Radeon cards. Currently getting into the system with nomodeset, but with limited resolution

Installing Ubuntu 16.10 solved it for me.
Starting with 16.04, the older AMD drivers were deprecated in favor of the newer open source ones from AMD.

Ubuntu 16.10 has the newer kernel (v4.8) and thus has better graphics support for AMD out of the box. Ubuntu 16.04 comes with kernel v4.4.

Alternatively, you can install the latest kernel from Ubuntu's mainline kernel PPA - http://kernel.ubuntu.com/~kernel-ppa/mainline/ and remove nomodeset from grub.


"/home partition" after formating and reinstalling Ubuntu 18.04 on "ext4 /"

What you describe is my SOP.

Do a backup, you are one ticked box away from losing it all.

When you go to do the fresh install, select "something else" option in the installer.

Tell it to use your / partition, mount it at /, and tick the format box.

Tell it to use your /home partition, mount it at /home, do not tick the format box.

Tell it to use swap if you have a swap partition.

Then proceed with the install.


If you would like to remove all the downloaded packages which done using either Terminal or Ubuntu Software Center, you could use the command sudo apt-get clean. If you want to remove everything of the installed packages, you could use the command sudo apt-get purge {package_name}, in your case, sudo apt-get purge eclipse.


card reader module throwing errors while installing rts_bpp

Have you actually tried to use your card reader even without this package working? There is a new driver in the Linux 3.8, rtsx, that is supposed to replace the rts. It works for me, at least.


PHP7.1 has been installed but php -v still show PHP5.6

That version has to do with the cli (command-line interpreter) version which you might not have installed so install it:

sudo apt install php7.1-cli

then check that version again. Noe remove the other version:

sudo apt remove php5.6-cli

if that is what it's called, then restart you server.


UBUNTU 16.04.6 not showing Dashboard, sidebars and menu bars

It seems the issue is with Python 3.5 package. Try running the command:

ln -s /usr/lib/python3.5/plat-*/_sysconfigdata_m.py /usr/lib/python3.5/

Then reboot

Hope it helps.

Thanks!


Get URL of current active tab from Firefox via command line

A solution has been provided here which is a combination of sed and python2. Here is a little bit more clear version of it:

sed -n "$(
python2 <<< $'import json
f = open("/home/username/.mozilla/firefox/RANDOM.default/sessionstore-backups/recovery.js", "r")
jdata = json.loads(f.read())
f.close()
print str(jdata["windows"][0]["selected"])')p" <(python2 <<< $'import json
f = open("/home/username/.mozilla/firefox/RANDOM.default/sessionstore-backups/recovery.js", "r")
jdata = json.loads(f.read())
f.close()
for win in jdata.get("windows"):
 for tab in win.get("tabs"):
  i = tab.get("index") - 1
  print tab.get("entries")[i].get("url")'
)

The file it's using is:

/home/username/.mozilla/firefox/RANDOM.profile/sessionstore.js

in more recent versions you should  change it with:

/home/username/.mozilla/firefox/RANDOM.default/sessionstore-backups/recovery.js

Note that this file get regenerated every 15 second so after window being instantly changed it doesn't give you the correct URL, you have to wait some second.

How does this work?

At the first part it look for the id of active tab, it's something between 1 to count of open tabs. let's say it's "3", the code corresponding to this purpose is:

str(jdata["windows"][0]["selected"])

Next it returns a list of URLs (All open tabs) and feds it to the stdin of sed:

for win in jdata.get("windows"):
 for tab in win.get("tabs"):
  i = tab.get("index") - 1
  print tab.get("entries")[i].get("url")

So we are doing something like:

sed -n 3p <<< "URL1
URL2
URL3"

which brings us to "URL3".


Why is Ubuntu asking to install alongside Windows Boot Manager?

Ubuntu is recognizing the installed OSes by the way they are identified in the system's (hard drive) configuration.  In this case, your Windows 10 is named Windows Boot Manager in the configuration.

The option you are seeing is the one that will install Alongside Windows 10, since the Windows Boot Manager is the reported OS.


How does this 'sed' substitution command with lots of @ signs work?

In sed, substitute commands are usually written as s/pattern/replacement/options. However, it's not necessary to use / - you can use other characters if it is convenient, so it could be s@pattern@replacement@options or s:foo:bar:g. s@+@ @g is like s/+/ /g - replace all + with spaces. Similarly s@%@\\x@g replaces all % with \x (a single backslash is an escape character in sed, so you need two to get an actual backslash).

A string like foo+%2Fbar will then become foo \x2Fbar. printf "%b" will expand the backslash-escaped sequences like \x2F (the ASCII character whose hexadecimal value is 2F, which is /) to finally give you foo /bar.


Installing Ubuntu after deleting Windows 8 - can it be installed in EFI (gpt) mode?

If your BIOS is Legacy, then format your Hard Drive as MBR for BIOS or MBR for BIOS/UEFI. If it is UEFI, format your Hard Drive as GPT for UEFI.


Try https://help.ubuntu.com/community/Boot-Repair I had to use it on numerous occasions - it never let me down!


HP Printer on Ubuntu 18.04 - Duplex (print on both sides) not working even though the option is available

Try this:
Download the file to ~/Dowloads
https://sourceforge.net/projects/hplip/files/hplip/3.20.6/hplip-3.20.6.run/download?use_mirror=nchc
Open a terminal and remove the previously installed version:
sudo apt remove hplip*

Cd to the location where the installer was downloaded.
cd ~/Downloads

To install run this command:
sh hplip-3.20.6.run

Select the install mode Automatic, enter an a
Ensure the installer detected the correct Linux distribution.
Enter Your root/Superuser User Password.
The installer will now detect what dependencies your system will need to install before installing HPLIP
If your system is missing any dependencies they are now downloaded and installed.
./configure prepares HPLIP for install as well as your system is verified to have all the required dependencies for HPLIP.
'make' is then executed. Make compiles ("builds") HPLIP for your system.
'make install' is the actual install procedure, this step is where HPLIP is actually being installed to your system.
Use 'hp-setup' to configure your printer.
The first step is to select the printer connection type.
Next the setup tool will display printers detected.
Select the PPD file to be Used for Your printer, usually you will want to select the recommended PPD file.
Click "AddPrinter" to complete the printer setup process.


Easiest method (as the Ubuntu Wiki suggests):

sudo dpkg-reconfigure mysql-server-N.N

replace N.N with the version of MySql.


It is possible to create multiple toolbars in Ubuntu 14.04, not just the default one?

I presume by toolbar, you mean the launcher on the left side of the screen in Unity.

No, it is not possible to create more versions of the launcher. However, it is scrollable, so if you overflow, the icons will fold at the bottom, and you can fit more items in the launcher.


Problem in installing Ubuntu 12.04 64 bit

(Everything I have read about Wubi indicates you should not use it!)
I recently installed Ubuntu 12.04 LTS, downloaded the file and burned to a DVD.
You can run Ubuntu from the DVD so you can try it out without installing it.
If you choose to install it is pretty easy, try dual-boot (mine is with XP).
There is a partition manager in the install program, I set my partitions about half & half between Ubuntu and XP. After installation a new bootup screen will appear which will allow you to boot either operating system. My XP still works fine, no problems.

My total installation time was around 2 hours including downloading Ubuntu and burning the DVD.

After that I spent HOURS checking out Ubuntu! There are a lot of programs included.
It recognized my network immediately and I was online doing email in minutes.
Also downloaded pics from my phone right away.

Good luck, you can do it!


How to change steam library location to another hard drive?

make sure your game partition mounted, if not, mount it.
open steam,Settings -> Downloads -> Content Libraries
click STEAM LIBRARY FOLDERS，ADD LIBRARY FOLDER, then chose your TF2 folder, and click ok.

If you chose your folder correctly, you can see your game in library.In order to not set library path everytime, you can change your partition to mount on startup using disk.


How do I communicate with Arduino Mega 2560 r3?

See this link: http://www.ladyada.net/learn/arduino/lesson0-lin.html

If it does not work, you can use:

sudo apt-get install openjdk-6-jre avr-libc gcc-avr

I have an Arduino UNO and went through the same problem.


Try the PPA: https://quodlibet.readthedocs.org/en/latest/downloads.html#ubuntu-logo-ubuntu

QL in Ubuntu 3.10 is quite outdated


How can I theme my Qt app to resemble one written in Gtk?

Note: this is useful to desktop users, not to developers using Qt.

sudo apt-get install qt4-qtconfig, then go to System / Preferences / Qt 4 settings and select GTK style in the first combobox:


Error changing between Nvidia and Intel GPU using Nvidia-settings (no module named 'dbus')

I had the exact same problem. I stumbled upon a solution.

Try switching GPU using terminal. It does not give an error then.

TO SWITCH TO NVIDIA GPU:

sudo prime-select nvidia

TO SWITCH TO INTEGRATED INTEL GPU:

sudo prime-select intel


Kubuntu:
showing a window on multiple destops works out of the box.
Just right click on the app icon in the task bar

select "Move to Desktop" >> "All Desktops"
This way the window is displayed on every "Desktop" (the wording "move" in the context menu is a bit misleading).
Gnome
As it turns out this works out of the box as well
Right click on the Window Title and select "Always on visible Workspace"