How can different packages have identical source code?

You're confusing built binary packages with the underlying source code/package that the packages were built from.

The packages you're referring to are all built from the same source code/package, mutter.  You can find that easily by going to packages.ubuntu.com, searching the package you're looking at, and then refer to the "Source package" it refers to.  Which in this case is mutter:

From there, however, we can check the Launchpad page for Mutter's source package and see that it builds a multitude of binary packages (built compiled source code, etc. for installation):

These descriptions describe what each package contains/installs.  Focusing on the 4 packages you indicated, and using these descriptions:

gir1.2-mutter-4 - GObject introspection data for Mutter (used by gir and GObject as libraries/data for Mutter and GObject interaction)
libmutter-4-0 - The underlying library for the Mutter window manager.  (Used for plugin development, development and compiling Mutter integrations, etc. usually)
mutter - the actual Mutter Window Manager that uses GNOME's Window Manager Library (which is why GObject is needed)
mutter-common - Shared Files for Mutter - usually default configuration options or items which are common to all the packages built from the source package.

What you're seeing in your package list are the built packages which originate from the same source code - each package is different items being installed after build/compile time and are used differently for different things.  You can see what's in the packages themselves by downloading the individual packages and then accessing them with p7zip or the in-built Archive Manager in Ubuntu and see the differences of what each package contains that way.  This said, they all originate from the same source code - they just contain different items that're being installed to the system.


The desktop cannot be created because its area is too large with ati card and dual monitors

You need to define your 2 screens in AMD soft.

Open ATI driver application

and define your 2 screens display without any limit.

and re-boot
you might see no changes, but to end the manipulaation, use then the normal Screen application to set your 2 screens.
And for new Ubuntu behaviors too like:

unity toolbar on only screen, or on both (in english it's got to be "launcher position")
mouse stuck on screen border (in english it's got to be "sticky border")


Does the Nexus 7 version of Ubuntu support the same software as the desktop version?

The Nexus tablet is not a full PC. It has an ARM CPU, which while having a pretty OK clock speed, doesn't necessarily perform well at some very CPU intensive tasks. It is designed for minimal power consumption. It also does not have the same instruction set as the x86 CPUs you're used to using in a PC. Therefore, some software will just outright not work or be available (such as VirtualBox), or may perform very poorly. You can see what packages are available by looking through the archive for binary packages built for the architectures armhf or all.

However, most software will be available, even though there are plenty of packages in the archive which only build on x86 architectures, or even on other architectures, but not ARM.


Installing Vbox Guest Additions in Ubuntu Server

You don't insert Guest Additions CD image you don't need to at all.

open up  a terminal and run this command to open up additional drivers.

sudo /usr/bin/software-properties-gtk --open-tab=4

Click on Using x86 visualization solution

Then click on apply Changes

If you wanted to Install this in terminal you would need to run this command.

sudo apt-get install virtualbox-guest-dkms


Edit gamefile/console database manually retroarch

Found the playlist and can manually edit them in /home/USER/.config/retroarch/playlists .
All my research is done and have managed to get it working successfully, will help answer what questions i can to get this solved for others.


There are many ics-related libraries. For example python3-icalendar package maybe used as base.
If you need scripting for Google Calendar - use gcalcli package.
Also take look at https://rainlendar.net.


How to make ubuntu installed on other HDD password protected on windows 7?

You can use encryption to protect the data on the Ubuntu drive, either full disk, home dir or just one directory.

There is no way to avoid that the disk can be formatted, short of disabling it in the BIOS or similar tricks.


error: Setup script exited with error: command 'x86_64-linux-gnu-gcc' failed with exit status 1

Answered in comments by OP:

  Solved. Python-snappy was missing


How to disable OpenVPN from autostarting at boot-up or reboot?

You have two options:

Run:

sudo update-rc.d openvpn disable

Then you'll have to run sudo service openvpn start to manually start the VPN.
Or edit the file /etc/default/openvpn

sudo gedit /etc/default/openvpn

And uncomment the line:

#AUTOSTART="none"

So it looks like:

AUTOSTART="none"

Then you'll have to run sudo service openvpn start <vpn-name> to manually start the VPN. <vpn-name> is the config file name without .conf.


To supplement the main boot options, the F1-F6 keys provide additional information and boot options for special circumstances.

These options are accessed by pressing any key before the Welcome screen appears.

F6 -- Other Options. ACPI and EDD options which may help if your computer does not support or has problems with these systems.
Highlight the selection and press the Enter key or Space key to select it.

In addition to displaying a popup menu, the F6 key also activates in-line editing of the boot command.

Pressing F6 brings up the popup menu. Pressing Esc, whether selections were made or not, removes the popup window but opens the boot command for editing.

The phrase Boot Options is fixed on the left side of the screen. The command scrolls off to the left to leave the right end available for appending.

The user may add additional inputs before or after the -- . Allow one space between each additional input.

Try add the acpi=off pci=noacpi options.


ir-keytable and Imon as MCE remote for Kodi

I managed to find an solution, so thought it best to post for others.  Its built from this youtube video:
https://www.youtube.com/watch?v=guMX3umfFG8
As he says the changes that happen when we use the "ir-keytable" command dont stick at reboot, so the solution is to use "systemd" to get the change to load everytime you restart. To do this, create a new file in:
/etc/systemd/system/
called "ir_remote.service"
Then in that file write:

[Unit]
Description= Remap IR Remote
[Service]
ExecStart=/usr/bin/ir-keytable -c -w /etc/rc_keymaps/YOUR_KEY_MAP.toml
[Install]
WantedBy=multi-user.target

This should then run when you reboot.
Good luck!


Samba stopped working... wrong interface?

Try only to add interface name after 127.0.0.1 in your global config

interfaces = 127.0.0.0/8 eth0


Alternatives to HydraPaper for dual monitor wallpapers?

This might be what you are looking for.

I did it using "bash", "convert" and "gsettings".
It works with my 2 screens.

In outline:

get two images with the same height
new width of image = width of screen * original height of image / height of screen
stretch image to new width
join the 2 images which now fit the full width of the 2 screens

I am running Ubuntu 18.04. Feel free to hack to your heart's content

#! /bin/bash
#! /bin/bash -vx

# input:
# new_background.sh -reset - to reset background to the previous picture
# new_background.sh -set - to set a new background

lastImage=$HOME/.new_background_last_image.txt
DIR="/usr/share/backgrounds"
joinImage=$HOME/.new_background_last_image.jpg
# choose 2 images from dir
number=$(ls -1 $DIR | wc -l | awk '{print $1}')
mapfile -t screenSize < <( xrandr | grep  -e "^DP" | awk ' { print $0 }'  )
if [ ${#screenSize[@]} != 2 ]
then
echo there don\'t appear to be 2 screens - jobs ends
exit
fi

tot=0
prevH=0
prevW=0
prevFile=""
found=0
SET=-1
case "$1" in
-reset ) SET=0
;;
-set ) SET=1
;;
esac

if [ "$SET" -eq -1 ]
then
echo enter either -set or -reset
exit
fi

# reset previous picture
if [ "$SET" -eq 0 ]
then
URI=$(cat $lastImage)
gsettings set org.gnome.desktop.background picture-options 'zoom'
gsettings set org.gnome.desktop.background picture-uri "${URI}"
exit
fi

# find 2 pictures
while [ $tot -lt $number ]
do
# go throguh files at random until 2 have the same height
  randomN=$[ ( $RANDOM % $number ) ]
  fileName=$(ls -1 $DIR/*  | grep -e jpg -e png | awk 'NR=='$randomN' {print $0}')
  if [ x$prevFile == x$fileName ]
  then
    continue
  fi
  if [ x"" == x$fileName ]
  then
    continue
  fi
  if [ x$prevFile != x$fileName ] && [ x"" != x$fileName ]
  then
    ww=$(convert $fileName -print "Size: %wx%h\n" /dev/null | awk '{ print $2}')
    w=$(echo $ww | awk -F x ' {print $1 }')
    h=$(echo $ww | awk -F x ' {print $2 }')
    if [ $h -eq $prevH ]
    then
      found=1
      break
    fi
  fi
  prevW=$w
  prevH=$h
  prevFile=$fileName
  tot=$[$tot+1]
done

if [ $found -eq 0 ]
then
  echo no files found   # may be solved by running the program again
  exit
fi

# new width = width of screen * original height of image / height of screen
#           =      1920                 2160(e.g.)           1080

pref=$(expr $(mktemp -u) :  ".*\.\(.*\)")
outputFile=(${pref}_1 ${pref}_2)

files=( $fileName $prevFile )
widths=( $w $prevW)
heights=( $h $prevH)

# do each file
reverse=0      # if the second screen is the first in the screenSize list reverse=1
for I in 0 1;
do
# size of screen I
mapfile -t tt < <(echo ${screenSize[$I]}   |  grep -E -o  '[0-9]+x[0-9]+\+[0-9]+\+[0-9]+'  | sed s'/[x+]/ /g' | awk ' { print $1,"\n", $2, "\n", $3, "\n", $4 } ')

# this is the start position of the screen
# if not 0 and I=0 then it is the 2nd screen and reverse images when joining
offset=${tt[2]}
if [ $I == 0 ] && [ $offset != 0 ]
then
reverse=1
fi
let "newWidth = ${heights[$I]}*${tt[0]}/${tt[1]}"
convert -resize ${newWidth}x${heights[$I]}! ${files[$I]} ${outputFile[$I]}
done

# join the files
if [ $reverse == 0 ]
then
convert +append ${outputFile[0]} ${outputFile[1]} $joinImage
else
convert +append ${outputFile[1]} ${outputFile[0]} $joinImage
fi

URI=$(gsettings get org.gnome.desktop.background picture-uri)
# save the previous file name
echo $URI > $lastImage
uri=file:"//$joinImage"
gsettings set org.gnome.desktop.background picture-options 'spanned'
gsettings set org.gnome.desktop.background picture-uri "${uri}"
rm ${outputFile[0]} ${outputFile[1]}
# end-of-file


Removing rstudio and its user from the system

Use sudo apt-get purge r-base.
This works like apt remove but also deletes configuration files.

After that, issue the following commands:
sudo deluser --remove-all-files rstudio
sudo deluser --group --remove-all-files rstudio
This will remove the system user created by the installer, which is not automatically removed by the uninstaller.


How do I change login screen theme or background in Ubuntu 20.04?

In previous versions of Ubuntu since its introduction of gdm3 for login greeter, the style sheet file is directly available to edit.
for example:
/usr/share/gnome-shell/theme/ubuntu.css #for Ubuntu 18.04
/usr/share/gnome-shell/theme/Yaru/gnome-shell.css` #for Ubuntu 19.10

are the files being used as alternatives.
The name of alternatives is gdm3.css.
for Ubuntu 20.04 the equivalent to above is gdm3-theme.gresource
$ update-alternatives --config gdm3-theme.gresource
There are 3 choices for the alternative gdm3-theme.gresource (providing /usr/share/gnome-shell/gdm3-theme.gresource).

  Selection    Path                                                           Priority   Status
------------------------------------------------------------
* 0            /usr/share/gnome-shell/theme/Yaru/gnome-shell-theme.gresource   15        auto mode
  1            /usr/local/share/gnome-shell/theme/focalgdm3.gresource          0         manual mode
  2            /usr/share/gnome-shell/gnome-shell-theme.gresource              10        manual mode
  3            /usr/share/gnome-shell/theme/Yaru/gnome-shell-theme.gresource   15        manual mode

Press <enter> to keep the current choice[*], or type selection number:

from the core files of Ubuntu, the config for gdm is
stylesheetName: 'gdm3.css',
themeResourceName: 'gdm3-theme.gresource',

the above means that one needs to edit the file gdm3.css inside the .gresource file from the above update-alternatives result. Or install some other .gresource files which have the compatibility for Ubuntu 20.04.
for example in above output you have the choice of
.../gnome-shell/gnome-shell-theme.gresource

as an alternative. If you trust some other (external sources) .gresource files that have the compatibility for Ubuntu 20.04,
You can install them as an alternative and use it.
If you want to edit,
for example, you can extract the gdm3.css and see the color that is configured for login screen background.
run the below commands one by one
gresource extract /usr/share/gnome-shell/theme/Yaru/gnome-shell-theme.gresource /org/gnome/shell/theme/gdm3.css > $HOME/gdm3.css
gedit $HOME/gdm3.css

some of the content:
#lockDialogGroup {
  background-color: #4f194c; }

Editing this content with your required content and recompiling it to create new .gresource file is required. After which you can install this new .gresource file as an alternative and select it.
How to extract and compile?
Disclimer: this  link  is only for Idea. Proper making and configuration is required for getting things to work for Ubuntu 20.04 Otherwise system will be bricked. Please note that this post is quite older and contents vary from Ubuntu 20.04.
Also note that the package libglib2.0-dev is required to compile the .gresource file.

Well, seems the process is very heavy just for changing the login screen background, rite? what if you want to change the background Image or color of the Login screen frequently?
 Workaround 1
go for this for complete flexibility. But risk of breaking the system if wrongly edited the contents. Of course recovery is easy also.
 Workaround 2
go for this for changing login background with Image/ Color with a script.
you can download the focalgdm3 file via command line
wget -qO - https://github.com/PRATAP-KUMAR/focalgdm3/archive/TrailRun.tar.gz | tar zx --strip-components=1 focalgdm3-TrailRun/focalgdm3

Once you downloaded the script focalgdm3.
Make sure you have installed the required package, libglib2.0-dev.
If not installed, Install it with the command
sudo apt install libglib2.0-dev

run the below command to set the Image as background..
sudo ./focalgdm3 /absolute/path/to/image

run the below command to set the Color as background..
(Change #aAbBcC with any valid Hex Color Code)
sudo ./focalgdm3 \#aAbBcC

to reset everything that the script made
run the below command with root privileges
sudo ./focalgdm3 --reset


LXC start error : setup_caps: 2337 unknown capability mac_admin

Install libcap-dev using

apt-get install libcap-dev

Then, recompile the LXC.


How do I copy a folder keeping owners and permissions intact?

Use the -p flag.

-p     same as --preserve=mode,ownership,timestamps

--preserve[=ATTR_LIST]
       preserve the specified attributes (default: mode,ownership,timestamps), if possible additional attributes: context, links, xattr, all

Note that for the permissions to be correctly replicated, the destination file system should be the same as the source file system. In other words, your external drive should be formatted as ext4 if, as is usually the case, your home folder is stored on a partition of that type.


I had a similar problem with my GTX 1080 when installing Ubuntu 16.04. It seems that 16.04 does not support the latest Nvidia GPUs. I finally managed to install Ubuntu 16.04 along side with Windows 10 dual boot with my GTX 1080 unplugged. What I did is as follow.

Before you install Ubuntu, go to BIOS setting and disable the GTX GPU. You may need to go through the BIOS settings for sometime to find the right option (something like IGX?).
Note that before you reboot, you need to switch your monitor's cable to the motherboard video output, since after reboot, the GTX GPU would be disabled and you would not see anything.
After that, choose the install media with UEFI, and go through the installation procedure as usual. The display should be alright.
At the position where it asks on which device you want the Ubuntu installed, choose manual setting (the something else button?). And make partitions as you like. But remember to choose the whole device (i.e. /dev/sda or /dev/sdb) to install grub. DO NOT choose something like /dev/sda1.
After the installation finished, reboot without changing graphical output device.
When you are in your newly installed Ubuntu, open a terminal and install the appropriate Nvidia driver. You may check this question for more details. It's basically sudo add-apt-repository ppa:graphics-drivers/ppa sudo apt-get update and find the right driver for you. Check this also.
Finally, reboot and change the graphical output device back to your GPU and everything should work normal. You can type nvidia-smi in a terminal to check if the driver is working.

One of my friend tried to install Nvidia driver from Ubuntu system setting. You may look into that as well. As for me, the above procedure works fine.


How do I compile face_landmark_detection_ex, which requires dlib?

You may be omitting some required -l flags, or you may be linking against the wrong version of dlib.
Besides -ldlib, you also need -llapack, -lblas, and -lgif.
This works for me on Ubuntu 16.04 LTS:
g++ -std=c++11 -o face_landmark_detection_ex face_landmark_detection_ex.cpp -llapack -lblas -ldlib -lgif

The output shown in your question indicates that, when you attempted to build the program, header files in /usr/local/include/dlib were found. This is not where the libdlib-dev package puts its header files, so the version of dlib you installed yourself, 19.4, is the one that is being used.

That is probably good. Not only is it newer, but I believe face_landmark_detection_ex is incompatible with Ubuntu's dlib because it is compiled with DLIB_NO_GUI_SUPPORT.
If you're not otherwise using the version of dlib provided by libdlib-dev and its dependencies, I recommend uninstalling them (see below).

Dlib is sometimes used without being installed, but it appears you installed it in /usr/local, perhaps with a method like the one given in step 3.1 here. Assuming you ran sudo ldconfig after installing it, and that the liblapack-dev, libblas-dev, and libgif-dev packages are installed, passing -llapack -lblas -ldlib -lgif to the compiler should produce a successful build:
ek@Io:~/src$ g++ -std=c++11 -o face_landmark_detection_ex face_landmark_detection_ex.cpp -llapack -lblas -ldlib -lgif
ek@Io:~/src$ ./face_landmark_detection_ex
Call this program like this:
./face_landmark_detection_ex shape_predictor_68_face_landmarks.dat faces/*.jpg

You can get the shape_predictor_68_face_landmarks.dat file from:
http://dlib.net/files/shape_predictor_68_face_landmarks.dat.bz2

You may want to pass other flags to the compiler to enable warnings and (as the source code's comments mention) optimizations.
I tried omitting various combinations of flags to get different errors, but I was unable to produce the specific linker errors you got, so perhaps more is going on here.
Uninstalling the System-Provided Dlib
To ensure that the older version of dlib (from when you installed libdlib-dev) is not interfering, as well as to prevent confusion, I suggest uninstalling it. One problem this can help solve is the possibility that the compiler is using headers for the dlib version you installed but the linker is using the system-provided version of the library. They are not compatible with one another.
Assuming you installed the system-provided dlib by running sudo apt install libdlib-dev and no other Ubuntu software is depending on it, these commands will uninstall it:
sudo apt remove libdlib-dev
sudo apt autoremove

The -dev package provides just the header files, but it causes the library itself to be installed as a dependency; the autoremove action removes packages that are installed just to satisfy dependencies of other packages that have since been removed.
If after this the dependencies are not all installed, you can add them back. For example, you might have to run this:
sudo apt install liblapack-dev libblas-dev libgif-dev

(If you like, you could do that first, before removing packages, to mark them as manually installed and prevent them from being removed in the first place.)
Then, I suggest uninstalling and reinstalling the version of dlib you installed manually, though just running sudo ldconfig again might be sufficient, if the version you installed is in no way broken. It might not even be necessary, but it should not cause harm.
One benefit of rebuilding and reinstalling dlib is that you will likely be informed if some of its dependencies are no longer satisfied.
When you install Dlib again, it might give you the option of using its own built-in version of a library that it depends on or installing the system-provided library. For example, if liblapack-dev and libblas-dev aren't installed, it may suggest you install them. If it does, I recommend doing that--for one, you may get better performance--and start the Dlib build over again.
If you do this and you get the same errors--or different ones--then please update your question with more information.


I found a solution, but quite accidentally.

Removing all extensions and reinstall Lightning didn't help.
I tried to change the language of Thunderbird, which didn't help too.
I also installed version 3.3.4, no change.
Then I tried to import a calendar-file (.ics), it loaded but didn't show anything (that's how I expected it). But then I reinstalled Lightning and the calendar shows up and is working. I didn't expect that to be possible, due to a probable loss of all Lightning configuration, but somehow it worked.


Start a live session, using the Ubuntu installation DVD.
Then in the live session, open a terminal and run on it:
sudo umount /dev/sda7
sudo fsck /dev/sda7

Then reboot
And boot from hard drive


Atom is not in the official repositories, so I assume you're installing it from a PPA. As the unofficial Atom PPA does not provide a version for Cosmic (18.10), you're probably installing the Bionic (18.04) package, so it's most likely a compatibility issue. I compared the dependencies between the PPA package and the downloadable DEB (dpkg -I filename.deb), and the former has GTK2 UI dependencies which are being dropped in favor of GTK3.

For now it's best you use the downloadable version, until (hopefully) that or another PPA starts providing a proper Cosmic version. Don't forget to check your software sources so that they're requesting a Cosmic version from the PPA instead of Bionic.

Brackets has similar GTK2 and other aged dependencies, so it may be very hard if not impossible to get it working properly on Ubuntu 18.10 until they modernize their code.

PPA (atom_1.26.1-1~webupd8~0_amd64.deb):
Depends: git, gconf2, gconf-service, libgtk2.0-0, libudev0 | libudev1,
         libgcrypt11 | libgcrypt20, libnotify4, libxtst6, libnss3, python,
         gvfs-bin, xdg-utils, libdbus-1-3, libcap2, libxkbfile1, libx11-6,
         libasound2, libsecret-1-0, gir1.2-secret-1

DEB (atom-amd64.deb):
Depends: git, gconf2, gconf-service, libgtk-3-0 (>= 3.9.10), libudev0 | libudev1,
         libgcrypt11 | libgcrypt20, libnotify4, libxtst6, libnss3 (>= 2:3.22),
         python, gvfs-bin, xdg-utils, libcap2, libx11-xcb1, libxss1,
         libasound2 (>= 1.0.16), libxkbfile1


Linux uses RAM very differently then Windows and I do not see any problem as long as you are not using swap.

See - http://www.linuxatemyram.com/

32 bit Ubuntu may use less RAM, you should boot a live usb and see before you install, but it is does not use significantly less

  32 bit: uses 388 MiB of RAM right after booting, no additional applications running (from the screenshot, 397780KiB, which is 388MiB)

  64 bit: uses 491 MiB of RAM (from the screenshot, 503452KiB = 491MiB)

What are the differences between 32-bit and 64-bit, and which should I choose?

The old adage - unused RAM is wasted RAM applies.

If you are running out of RAM, you are going to get more bang for your buck by increasing your RAM or using light weight applications, a lighter weight distro, such as lubuntu, over 32 bit Ubuntu.


In which drive my data is getting stored in Ubuntu

Ubuntu does not use drive letters; it sees all of its available space as one large tree. It lists your Windows drive (which is called "C:" in Windows) as one of its "Devices", as you mention, but that is just a matter of convenience: in Ubuntu terms that is probably a folder called /media/long-complicated-drive-name/.The fact that you can see more files in Ubuntu than in Windows is more like a Windows trick: under Ubuntu you will see all files and directories, whereas Windows hides these from you.The boot, etc, dev, root, run etc. are system folders where you shouldn't store anything, and in most cases, the system won't even let you. Feel free to organize your own files in the /home/username folder. That one is comparable with the folder called "username" under Windows. Ubuntu does not care how and where you store things in /home/username, except for personal settings which are typically in folders starting with a ".".
From the Windows perspective, whether your Ubuntu system is stored in D: or J:, or somewhere else, is impossible to tell without more information.


Plasmashell High CPU Load Fix - Plasma 5.15 KDE on Kubuntu 19.04

Editing the /usr/share/plasma/plasmoids/org.kde.plasma.notifications/contents/ui/NotificationIcon.qml file seems to do the trick (your mileage may vary). Look for this section:

PlasmaComponents.BusyIndicator {
    anchors.fill: parent

    visible: jobs ? jobs.count > 0 : false
    running: visible
}

..and change it to read:

 PlasmaComponents.BusyIndicator {
    anchors.fill: parent

    visible: jobs ? jobs.count > 0 : false
    running: false
}

Essentially, just replacing the "visible" with "false"

Restart/reboot, and it may work fine.


Installing ubuntu on Clean Mac Intel / new HDD

Sorry it took so long to get back to you!

A1:

Yes, you want the ubuntu-14.04-desktop-amd64.iso. I'm not entirely sure why the Linux community refers to all 64-bits as "amd64" exactly. However, rest assured that the "amd64" variant simply means "64-bit" and will work on any 64-bit AMD or Intel processor (internally, they're pretty much the exact same thing).

A2: Yes, you can create an EFI partition from Windows 7.

Type 'diskpart' into the start menu search and press enter
Use the following sequence of command to set up your EFI disk:

list (take note of the disk you want to use. mine was the second disk, #1 in my VM)
select disk [disk number]
list partition (just to make sure you have the right disk selected, it should show no partitions)
convert gpt
select partition 1
delete partition override
create partition efi size=100

Now you should be all ready for an Ubuntu install! Just use the "Use entire disk" option when the installer asks and you should be done.


Why doesn't the nova-cloud-controller charm properly set up openstack networking?

I've had the same problem. Also the vnc packages is also never installed. It seems to me that the charms is not fully functioning, or i may be missing something...

However i made it work by setting up the networking my self.

Created a bridge 'br100' and made sure the interface linked to the bridge was set for promiscuous mode. This has to be done on controller and all compute nodes. Then of course you have to update nova.conf with the right information and use the command nova-manage to  create the networks.

This blog post was crucial for me:
http://www.mirantis.com/blog/openstack-networking-single-host-flatdhcpmanager/


Verifying that Google Chrome is updating in 16.04 LTS

Those Ign and Hit doesn't mean that the Chrome Update has occured. See below answer from @Anwar.

  Hit means apt needed to download a Release file or InRelease file (because somehow it got deleted) and once it is downloaded, it checked the checksum of the Index file in it and found that the checksum mentioned there matches the checksum of the Package file already downloaded that is in /var/lib/apt/lists. That's why it's a Hit. So, it won't download the Package file again.
  Ign means apt tried to download something (such as translation or InRelease file) but didn't find, but that can be ignored, so proceed to the next thing. Because translation can be secondary priority and if InRelease file can't be found, it uses other method for authentication like using Release and Release.gpg pair.

Nor the AppStream cache update completed, but some metadata was ignored due to errors. cause update to chrome, it was a bug.

To check whether chrome is updated. Click the Chrome menu  on the browser toolbar and select About Google Chrome.


I had the exact same problem with my Dell Inspiron 14z. I removed the RAID info on sda explained in this answer. It worked for me, without destroying the current Windows 7 installation. The SSD seems to be used for hibernate/sleep in Win7, and that still works after removing the RAID info.

It might be possible to install ubuntu on the SSD (sdb), but I could not find the disk in the partition step during installation, so I installed on sda.


How to disable automount for internal partitions?

Do nothing. Partitions on internal disks for which you did not specify a mount point at install time, are not automatically mounted (until you try to open them in the file manager). They will however, still show up on the launcher by default, as well as in the file manager, so that you can access them.


How do I choose a Java installation package?

You should explicitly select one to install. means you need to issue command to install 1 of the 3 suggested packages, which provide similar functionality of openjdk-7-jre-headless which is currently unavailable. You can issue command like these

sudo apt install oracle-java9-installer or
sudo apt install oracle-java8-installer or
sudo apt install oracle-java7-installer

As a note, you should know that, there is no component of OpenJDK-7 in xenial release and therefore openjdk-7-jre-headless package is non-existent. See here http://packages.ubuntu.com/search?keywords=openjdk-7-jre. OpenJDK-7 has been dropped in the latest LTS and you need to install openjdk-8 or openjdk-9 to use openjdk (in contrast to Oracle JDK)

I suggest using openjdk-8 instead and replace all the packages containing name openjdk-7 with openjdk-8 and proceed with installation. This will resolve the issue for Xenial.

If you really want to stay with OpenJDK 7, Look at this question

How do I install openjdk 7 on Ubuntu 16.04 or higher?


How to move 513MB healthy logical drive partition

You should be able to do this with GParted if you boot into a live environment. The key is to extend partition 4. These are the steps:

Backup any data anywhere on the drive that you cannot afford to loose.
Boot into the live environment. (Try Ubuntu)
Using GParted resize partition 4 (it’s a container for partitions 3, 5 and 6). Move its start point next to partition 2. That will move the unallocated space inside partition 4. Apply the change.
Move partition 5 to the start of partition 4. That will move the unallocated space next to partition 6. Apply the change
Resize partition 6 to make use of the unallocated space. Apply the change.

That’s it. Reboot and your Linux partition should have more space available
Good luck


Have a look at xrandr. Called without arguments it shows connected screen(s) and the supported resolutions. For example:

$ xrandr

HDMI-1 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 510mm x 287mm
   1920x1080     60.00*+
   1280x1024     60.02
   1440x900      59.90
   1280x800      59.91
   1152x864      75.00
   1024x768      70.07    60.00
   800x600       60.32    56.25
   640x480       66.67    59.94
   720x400       70.08

Changing resolutions:

$ xrandr --output HDMI-1 --mode 1280x1024
$ xrandr --output HDMI-1 --mode 1920x1080


LDAPS with snap install of nextcloud on 18.04

I managed to get it working via a workaround, by using stunnel:
[ldap]
accept = 389
connect = <ldap server>:636
client = yes
CAfile = /etc/stunnel/ldap.pem


You are better off with a full install.

Persistence uses a cow (copy on write) overlay file. the cow file keeps getting larger and larger and often fails.

Persistence is helpful, IMO, if you want to keep your user or system settings and/or data in /home between boots.

Persistence is "OK" when you install a few packages.

Persistence fails when you try to use it as a substitute for a standard install and update all the packages or install a large number of packages.

Persistence fails when you try to install proprietary drivers such as nvidia or ati.

So, with a 16 Gb drive, IMO, you are better off doing a standard install.


Shift running X window (display environment) on SSH X11 forwarding

Thank you folks, but another friend found a better answer, I want to share with the world for someone with the same problem:

There is some tools such as xmove and Xpra that works as a X proxy, allowing you to retain the window opened in a kind of virtual X Server, and catch the window to your environment when you need, exactly what I need!

Thanks dudes.


Getting Permission denied (publickey) when login through ssh

If you have changed your SSH setup including having the wrong file permissions on .ssh/authorized_keys, you will need to do a recovery process if you cannot login:

Before making any changes, create a snapshot of your system (or create an AMI) just in case you make your problem worse.

Start a new EC2 instance.
Stop the broken EC2 instance.
Detach the root (boot) volume from the broken EC2 instance.
Attach the volume to the new EC2 instance as additional disk.
Mount the file root file system to a temporary directory.
Troubleshoot and fix the problem. In your case set the correct
file permissions.
Detach the volume from the new EC2 instance.
Attach the volume to the broken EC2 instance.
Start the broken EC2 instance.
Verify everything works. Go back to Step 2 to repeat.
Terminate the new EC2 instance when no longer needed.


How to increase space in /home, by adding an extra hdd?

Here are two packages that can merge two partitions in a single mountpoint:

unionfs-fuse - Fuse implementation of unionfs
mhddfs - file system for unifying several mount points into one


Difference between core temp and cpu temp

AMD Temp Information and Guide

  We've had a few great threads recently where members contacted AMD and asked what temps they should be looking at, what the max temp was on, and what programs should be used and why. But this information is still scattered and not well defined in one place. It also doesn't quite explain when you should be looking at certain temps. Well I've made it my mission to insure that people are reading the right temps and have been trying my best to give all the information each time I respond without sounding like a broken record. So I decided to write this information thread and little guide to help you out there.

  What is "Core Temp" ?

  "Core Temp" is what AMD refers to as "TCTL" and is a non-physical temperature on an arbitrary scale measured in degrees. It does not represent an actual physical temperature like die or case temperature.

  What is "CPU Temp" ?

  "CPU Temp" is read by a sensor in the socket of the motherboard.
  It is a physical temperature and therefore will be effected by ambient temps inside the case.

  Why should I use "Core Temp" and when?

  AMD designed this equation to accurately read peak (45C+) and load temps. It has an equational offset to determine said temps which equalizes at 45C. Since it's designed for peak temps and is a non-physical temperature it cannot read idle temps or account for ambient temps correctly.

  So what is "CPU Temp" good for then?

  At peak temps this value is typically 7-10C higher (depending on motherboard) than the actual temp due to it being a physical sensor. At idle it's a little more accurate, but still not dead on, and besides idle temps do not matter near as much as load temps do.

  AMD says my chip has a [INSERT SPEC] Celsius limit, what value is this referring to? This limit seems kind of low, why?

  This is referring to "Core Temp" of course.

  So for example Phenom IIs have a recommended 62C "Core Temp" limit while not exceeding 60C for extended periods.

  It has long been argued that the recommended limit is merely a larger safety net. There is a thermal shutdown in the chip at 90C and the silicone is rated for 97C+, so it seems plausable that we could indeed go higher, but this guide (and most in general) will simply nod and point you to the recommended limit for your chip.

  What programs read "Core Temp" ?

  AMD recommends the Core Temp program and AMD Overdrive for this reason.

  The core section of HWMonitor also reads this value, but be careful as it also shows CPU Temp.

From http://www.overclock.net/t/1128821/amd-temp-information-and-guide


Restore with back in time after fresh install of ubuntu

EDIT: There are two more detailed articles on BackInTime FAQ on how to backup and restore package selections.

Yes. This will work. Make sure you have included everything that is important to you in your last snapshot.
Run this commands to backup your PPA's and package selection:

mkdir ~/.apt-backup
sudo dpkg --get-selections > /home/<USER>/.apt-backup/package.list
sudo cp -aR /etc/apt/sources.list* /home/<USER>/.apt-backup/
sudo apt-key exportall > /home/<USER>/.apt-backup/Repo.keys

Just to make sure there are no corrupt files in snapshot you should run one last snapshot with Use checksum to detect changes enabled in Options on your old machine. (starting from 1.0.28 there is a command-line option --checksum for this, too. So you don't need to enable and than disable it again anymore).

Setup your new machine, install backintime again and copy config from your last snapshot folder /path/to/backintime/HOST/USER/1/SNAPSHOT_ID to ~/.config/backintime/.

If Backintime doesn't find your old snapshots directly, go to Settings disable Auto Host - User - Profile and change Host and User entry so they match your old machine.
Now restore your home directory (and all other folders which are important to you).

Recreate your /etc/apt/sources.list if you had set something special in there. If your Ubuntu version changed don't just copy them from ~/.apt-backup/sources.list

Restore apt-keys for your PPA's with sudo apt-key add ~/.apt-backup/Repo.keys

Make some "housecleaning" in ~/.apt-backup/package.list. For example you don't want to install the old kernel again. So run sed -e '/^linux-\(image\|headers\)/d' -i ~/.apt-backup/package.list

Finally install all your old packages again with:

sudo apt-get update
cat ~/.apt-backup/package.list | sudo dpkg --set-selections
sudo apt-get dselect-upgrade


One way out of this, if you don't care to lose the data associated with the snaps, is to run Zyga's reset state script.

Also, please make sure you're on snapd 2.0.3, which was released to xenial last week; that way you shouldn't get into this state again.


Open up new terminal and run script with double click in Unity

You can use gnome-terminal with the --disable-factory option that does:

"Do not register with the activation name server, and do not reuse an already running GNOME terminal process"

It will let the 'commands' environment variable through.

gnome-terminal typically runs in a server mode. First launch starts a process, next launches send messages to main process to open a new window. So, env vars are set only on the first launch.
You can use a separate script file and pass its file name to bash. Or make it clever: detect inside this script its actual file name and pass it to bash, so it'll call this same script inside the gnome-terminal (but pass a parameter to take a different code path).
You can stuff everything into a variable, but make sure that it expands before the call to the gnome-terminal.


It's the scrolling animation. Nautilus and gedit now include an effect for when you scroll. If, however, your GTK theme isn't compatible with those animations, that happens. Just update your theme or switch it for another.


Acer R7 -- Broadcom wireless driver does not load

OK so here's how I fixed this.
For anyone wondering, this is for when your fresh Ubuntu install can't access the internet (Bleh)

Essentially the problem is that Ubuntu did not install the driver package.
So it's a straightforward problem, but a wee bit complicated to fix.

So, first,

I read this thread here.  I followed Luis Alvarado's post (currently the #2 solution.)

lspci -nn -d 14e4:
I looked up in his table to confirm I needed bcmwl-kernel-source installed, which btw, Ubuntu had already told me both my driver and missing source file when I tried to install the driver
I installed Ubuntu 14.04 Linux Live with a 4GB persistent partition to USB stick (persistent allows the USB drive to keep updated software installed between boots)
booting from here, my Wifi worked.  I installed Synaptic install manager

sudo apt-get update
sudo apt-get upgrade
sudo apt-get install synaptic

I loaded synaptic and found bcmwl-kernel-source and told it to reinstall
I did NOT hit apply, I went to file and created a download script
I saved this to the desktop, made it executable, and tried to run it.  It didn't work
I pulled from the script the DEBIAN filename (.deb) that I needed, googled, and downloaded it.  I stuck it on my windows partition so I could carry it over to the new install.
REBOOT to Ubuntu (the broken one without the drivers)
I double click the .deb file and then try to install it.  IT FAILS
I click on the detail link and grab the name of the 4 missing prerequisite files I need  (this probably varies from install to install etc etc)
I go back to linux live, download the files, REBOOT to Ubuntu
I install the .deb files in the order given in the order fail details
BOOM, my wireless adapter started working

If anyone knows how to pull the files straight from Linux Live Disk, I think that answer might be easier for people.


How do I  start jobs as a non privileged user in Upstart?

There was some progress with the release of version 1.4.:

  New “setuid” and “setgid” stanzas to allow system jobs to be run under the specified uid/gid corresponding to the given name/group.

You can grab it from their LaunchPad page but (strangely) I can't see a PPA so you might have to compile it yourself.

Otherwise, use su or sudo in your exec command like so:

su -c "<commands>" <username>
sudo -u <username> <commands>

They both do pretty much the same thing so pick whichever you're happiest with. So using your example command:

exec sudo -u me "nzbget -D"


That tutorial gives you the GNOME Fallback desktop enviorment. GNOME Fallback has NO Activities menu thats why you have no hot corners or Superkey functions. GNOME Fallback is GNOME 2's panel ported to GNOME 3.

It seems that your trying to install GNOME Shell (or Classic which comes bundled with GNOME Shell) rather than GNOME Fallback which you can find a tutorial here


Is there a kdeedu package alternative in 15.04

Here's a list of the dependencies for kdeedu available in Ubuntu 14.10 (http://packages.ubuntu.com/utopic/kdeedu).  These individual packages are still available in Vivid, even though the kdeedu package is no longer in the repositories.

blinken (>= 4:4.11.3) KDE version of the Simon electronic memory game
cantor (>= 4:4.11.3) interface for mathematical applications
kalgebra (>= 4:4.11.3) algebraic graphing calculator
kalzium (>= 4:4.11.3) periodic table and chemistry tools
kanagram (>= 4:4.11.3) jumble word puzzle
kbruch (>= 4:4.11.3) fraction learning aid for KDE
kgeography (>= 4:4.11.3) geography learning aid for KDE
khangman (>= 4:4.11.3) Hangman word puzzle
kig (>= 4:4.11.3) interactive geometry tool for KDE
kiten (>= 4:4.11.3) Japanese reference and study aid for KDE
klettres (>= 4:4.11.3) foreign alphabet tutor for KDE
kmplot (>= 4:4.11.3) mathematical function plotter for KDE
kstars (>= 4:4.11.3) desktop planetarium for KDE
ktouch (>= 4:4.11.3) touch typing tutor for KDE
kturtle (>= 4:4.11.3) educational programming environment
kwordquiz (>= 4:4.11.3) flashcard learning program
marble (>= 4:4.11.3) globe and map widget
pairs (>= 4:4.11.3) memory and pairs game
parley (>= 4:4.11.3) vocabulary trainer
rocs (>= 4:4.11.3) graph theory IDE
step (>= 4:4.11.3) interactive physical simulator for KDE

All of these packages can be installed in 15.04 using...

sudo apt-get install blinken cantor kalgebra kalzium kanagram kbruch kgeography khangman kig kiten klettres kmplot kstars ktouch kturtle kwordquiz marble pairs parley rocs step


Ubuntu 16.04 LTS is too old to be able to resize encrypted partitions using GUI. Actually gparted only supports resizing luks partition in unreleased development code (at the time of writing).

But you can try some Live CDs with KDE Partition Manager, e.g. try KDE Neon live CD (you still need to install KDE partition manager on live cd when you boot).


How can I make an application start up when I login?

Open the Dash (press Super key, or "Windows" key) and type:

 Startup Applications

Open the resulted application.

Now open up the Dash again and this time type:

terminal

Now drag&drop the resulted application to the earlier opened Startup Applications.

Now  if you want you can test this by logout and log in again.

COnsider creating custom scripts and add them as comands in your Startup Applications


Code::Blocks might be an option.

Code::Blocks is a free C++ IDE built to meet the most demanding needs of its users. It is designed to be very extensible and fully configurable.

An IDE with all the features a developer need, having a consistent look, feel and operation across platforms.

Built around a plugin framework, Code::Blocks can be extended with plugins. Any kind of functionality can be added by installing/coding a plugin. For instance, compiling and debugging functionality is already provided by plugins!

Runs on windows too
I'll let someone else post about codelite and widestudio so you can pick one


How can I fix my desktop background setting?

The simplest way to do this is to hit open a Terminal or hit Alt-F2 and run the command:
unity --reset.

If this doesn't work, (most likely it won't),for 13.10 follow this link


How to view similar commands in terminal?

Just to be clear what kind of editor did you mean by veditor?

Looks to me like a typo.
If you type in editor a predefined text editor will start. In my case itś Nano.

Other editors you can use are gedit, vim, vi, etc.

Even man -k veditor doesn't even show suggenstions.


I used Bumblebee to ruin my display resolution. How can I change it back to default settings?

Press   ctrl+alt+F1 ,it opens console.
Login into the console by putting your Username and Password.
After logged in run the below commands,

sudo rm /etc/X11/xorg.conf
sudo shutdown -h now
After power on your pc,you will getback to your original resolution.


Always mount a disk (flashdrive) with a particular label to the same mountpoint

All of the parameters of the following how-to are explained in the official Ubuntu documentation for fstab

Insert the USB drive
Go to a terminal and type sudo blkid and you should receive the following output:

/dev/sdb1: LABEL="BACKUP" UUID="mmmmmmmm-nnnn-oooo-pppp-qqqqqqqq" TYPE="szFileSystem"

If the label does not say "BACKUP", you made a mistake in assigning a name to your stick. Open gparted, unmount the volume and set the correct label.

In the same terminal, type sudo md /media/BACKUP
and: chmod -w /media/BACKUP
and: sudo nano /etc/fstab/
Download a nice square back-up icon and save it to /usr/share/pixmaps in png format.
At the end of the file add:

UUID=mmmmmmmm-nnnn-oooo-pppp-qqqqqqqq /media/BACKUP szFileSystem nosuid,nodev,noexec,users,nobootwait,nofail,ro,comment=x-gvfs-show,comment=x-gvfs-icon=NiceBackupIcon,comment=x-gvfs-name=BACKUP   0   2

where:

mmmmmmmm-nnnn-oooo-pppp-qqqqqqqq is the UUID from step 2
szFileSystem is the file system from step 2
NiceBackupIcon is the icon you downloaded in step 6 (note: no png file extension)


This is easy to enable from the CompizConfig Settings Manager. (Install it, if you haven't already).

Then under Window Management, enable Grid. I've kept the default bindings of CTRL+ALT+NumPad but you can easily change it Super + Arrow as you prefer.


Within nano, the most common keyboard shortcuts are displayed at the bottom of the terminal window for your reference.  This means there is no need for you to intentionally memorize them, or to stress over knowing them.

The more you use any text editor, the more comfortable you will become and the easier it will be to make changes quickly and efficiently.

Here is an overview document to help you learn nano:

https://www.howtogeek.com/howto/42980/the-beginners-guide-to-nano-the-linux-command-line-text-editor/

I don't recommend changing the nano default key bindings (shortcuts) but you can if you want by editing the nanorc file:

sudo nano /etc/nanorc

You can learn about the contents of the nanorc file within its corresponding man page:

man nanorc

Learning to use the terminal is about more than just using a text editor.  It's about becoming comfortable using the keyboard to interact with and change a system.  It's about learning to navigate the directories, and about using commands to quickly find and execute what you want to do.

Like many things, it's a process, and any time you spend using the terminal (or linux in general) will help you improve.


Does netplan support DHCP and static addresses on one interface?

The solution was quite simple, just set a static IP address and enable DHCP. Basically you just have to add dhcp4: yes to your configuration.

This configuration gave me a primary static IP address and a secondary DHCP assigned IP address:

network:
  version: 2
  renderer: networkd
  ethernets:
    enp0s3:
      dhcp4: yes
      dhcp6: no
      addresses:
        - 10.1.2.15/24
      gateway4: 10.1.2.1
      nameservers:
        search:
          - example.com
        addresses: [10.1.2.10]

The result of ip address show enp0s3 gave me:

2: enp0s3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 08:00:27:ab:cd:ef brd ff:ff:ff:ff:ff:ff
    inet 10.1.2.15/24 brd 10.0.1.255 scope global enp0s3
       valid_lft forever preferred_lft forever
    inet 10.1.2.96/24 brd 10.0.1.255 scope global secondary dynamic enp0s3
       valid_lft 3224sec preferred_lft 3224sec
    inet6 fe80::a00:27ff:fe20:2c40/64 scope link
       valid_lft forever preferred_lft forever

The address 10.1.2.96 is the secondary DHCP assigned address as indicated by the secondary dynamic keywords.


Zoom Cloud meetings is unusable because of an issue with display

Found a workaround!

I installed gnome tweaks and under Appearance, Themes, Applications, I changed from Yaru to Adwaita-dark and now the zoom client looks ok.

Now I would have to get used to a lot of dark looking applications, but at least I can I put that setting in when I need the app.


You can do:

$ array=( 2, 4, 6, 8, 10, 12, 14, 16, 18, 20)

$ echo "${array[@]/,/+}" | bc
110

${array[@]/,/+} is a parameter expansion pattern that replaces all , with + in all elements of the array
Then bc simply does the addition

Let's break it up a bit for clarification:

$ array=( 2, 4, 6, 8, 10, 12, 14, 16, 18, 20)

$ echo "${array[@]/,/+}"
2+ 4+ 6+ 8+ 10+ 12+ 14+ 16+ 18+ 20

$ echo "${array[@]/,/+}" | bc
110


Why is Chrony taking over network time sync responsibilities?

See bug report LP:1744072:

  Rationale:

  2.1 NTP in general is needed quite a lot, but we want to exchange ntpd
   which is the current implementation in main with chrony for 18.04.

  2.2 Security: chrony was considered easier to be maintained easier in
   terms of security and provide a more modern ntp experience as well.

  2.3 Efficiency: Furthermore several cloud people seem to be interested to
   change to chrony in the guests for its lower memoy/cpu footprint
   (efficiency I guess).

  2.4 related to this MIR 6 years ago this is the same but for Fedora.
  See: https://fedoraproject.org/wiki/Features/ChronyDefaultNTP
  IIRC some limitations that were present have been eliminated since, so
  it is even better than it was back then.

  2.5 In general one has to realize that in a systemd-timesync world
  ntp/chrony are mostly for the "serving" portion of an ntp service, and
  not so much about the client (unless you the better accuracy vs
  timesyncd is needed).


How to enable the CONFIG_PM_ADVANCED_DEBUG kernel configuration option

Duplicate question: What is kernel configuration?


I have found out that the problem seems to be the fact that the audio driver currently doesn't turn on the sound card's S/PDIF output channel, which allows normal volume control. Unfortunately, this meant I had to boot into Windows and install the ASUS-supplied driver there, which seemed to have persistently enabled S/PDIF on the sound card. Now I just can select "Digital Output (S/PDIF)" in the Ubuntu audio preferences and everything works perfectly.

I have reported a bug in Lauchpad and hope this will be fixed in future Ubuntu versions so that others won't need this workaround.

https://bugs.launchpad.net/ubuntu/+source/alsa-driver/+bug/1077829


Audio output device just producing a clicking sound

I have absolutely no idea how this happened but if anyone else comes across this thread I fixed the issue.
Fix: Opened alsamixer and played with the different Input Response channels.  Setting one of them to 0 fixed the problem.
I'm going to do some searching to learn about impulse response, but if anyone reads this that knows about it, feel free to chime in!


Create multiple files from a template referencing a single txt file and touch

A bash-esque way to do it (without an explicit loop) might be

read the filenames into a shell array variable

mapfile -t files < foo.txt

or its synonym readarray -t files < foo.txt
expand the array inside a tee command

tee < template.txt -- "${files[@]}" > /dev/null

[The > /dev/null is optional - it just hides tee's default standard output from the terminal.]


rebooting from dvd but keeps starting windows 7

Are you sure you burned the DVD correctly?  What's happened to me before is the burning software burned the *.iso directly to the disc, instead of copying the contents of the image to the disc.  It's a frustratingly simple solution if you've already checked the BIOS boot properties.


Why is program not executed even though it is in my path?

Your shell probably remembers an old file that doesn't exist anymore. Try rehashing:

hash -r


Mount fat32 partition with 777 permissions

If you use the flash drive with LINUX ONLY, I suggest you reformat and use ext2 or ext4.

If you use it with Windows, you ccan use fat, use this entry in fstab

/dev/something  /mnt/something  noauto,users,uid=1000,gid=100,dmask=0000,fmask=0000,utf8  0  0

you can change the uid or gid if you wish.


I'm suspecting you didn't install grub correctly. If your main hard disk is /dev/sda and Ubuntu is installed on say /dev/sda3, you should have installed it on the MBR of /dev/sda.

I suggest you boot from your Ubuntu disc, install boot-repair (sudo apt-get install boot-repair) and let it repair your bootloader.


How can I synchronize my Funambol with Thunderbird / Lightning

AFAIK, there are only "inofficial" builds of the Funambol add-on for thunderbird. Take a look at memotoo.com's site, there are build for Windows, Linux 32/64 bit and even OS/X. The site is in german, but you can set the language to english using the controls at the very top of the page.

At the first page, look for the buttons to select your application (you may have to scroll until you get the thunderbird icon):

Click on thunderbird icon to get the download links displayed:

Now, just download the add-on that matches your thunderbird and ubuntu version (32/64 bit). There's even a short documentation how to install the add-on (of course, you'll have to adapt the url to point to your funambol provider).

I'm using those add-ons with lucid, oneiric and with Win7 - works like a charm!


Is it safe to enable fast boot in Windows 8 while mounting windows partition as read-only in Ubuntu?

It is dangerous to write on NTFS partition while Windows uses hybrid boot

Ubuntu will refuse to mount an unsafe NTFS partition writable. So it is not a matter of "dangerous"; it is a matter of Ubuntu not letting you.

If you would be able to write to it the next time you boot into Windows those changes would be gone. That is what you would call "data loss".

  now I wonder if it is safe to access the partition in Ubuntu or not?

As read only it is safe. You can not alter the disk so when Windows boots the disk it is as it was when it was hibernated.


How do I customize GRUB to choose enter the text mode or enter the graphical mode

You want to use the 40_custom file for this, preferably in maintenance mode.

All commands in this tutorial are to be run as root! This tutorial also DOES NOT WORK for systems with /boot on a different partition!

Find the UUID of your main partition by using blkid and looking for an EXT4 partition. Remember this UUID, you will need it soon.
Start by opening the 40_custom file.

nano /etc/grub.d/40_custom

Append this to the end of the file:

menuentry "Ubuntu Text Mode" {
     recordfail
     gfxmode $linux_gfx_mode
     insmod gzio
     insmod part_msdos
     insmod ext2
     set root='(hd0,msdos9)'
     search --no-floppy --fs-uuid --set=root [UUID from earlier]
     linux /vmlinuz root=UUID=[UUID from earlier] ro text $vt_handoff
     initrd /initrd.img
}

Save this file as 15_custom. It will be after the Ubuntu default entries. Name it to 06_custom if you want it before default Ubuntu.
Run the following command, based on your system:

chmod a+x /etc/grub.d/06_custom
chmod a+x /etc/grub.d/15_custom
Finally, run this command to refresh the GRUB menu:

update-grub

Source for this tutorial is available here, free of charge.


Where does Ubuntu look for shared libraries?

This whole path business is related to something called multi-arch.
Basically it's to allow you to have 32bit and 64bit libraries on the same system.

After you copied the file, did you happen to run ldconfig?

ldconfig  creates,  updates,  and removes the necessary links and cache
       (for use by the run-time linker,  ld.so)  to  the  most  recent  shared
       libraries  found  in  the directories specified on the command line, in
       the file /etc/ld.so.conf, and in the trusted directories (/usr/lib  and
       /lib).   ldconfig  checks the header and file names of the libraries it
       encounters when determining which  versions  should  have  their  links
       updated.  ldconfig ignores symbolic links when scanning for libraries.


How do I set up a single Hard drive as a node on my MAAS server?

MaaS is designed as a tool for managing multiple physical machines, not multiple hard drives. (If your goal is to manage hard drives, then there are tools that do not require MaaS).

If you have a powerful enough server, you could use virtualization software like KVM or Virtualbox to create a couple of virtual machines, which you could then manage with MaaS. The only reason I can see to do this though is to test MaaS -- if you are trying to manage many (or even just a few) virtual machines, there are easier ways to do it, like Libvirt.

(I know my answer doesn't have a ton of specifics, but that is because I'm not sure what you are trying to accomplish, or what you end goal is).


In your ~/.ssh/config on your old computer, you should have a line similar to the one below,

Host server
  IdentityFile ~/.ssh/id_rsa

This is what tells ssh to use the key without having to specify it manually.


Is there a way to install Ubuntu next to Windows 10 , using Encryption and LVM without disk erasing?

Of course.

You need to create an unallocated partition and then can install Ubuntu into that space.


How do I add a Canon Pixma MX860 network printer?

I found workarounds.

Printing

The network printer can be installed if you enter the URI manually. When adding a new printer, select EnterURI from the devices list and enter cnijnet:/01-23-45-67-89-AB where 01-23-45-67-89-AB is the MAC address of the printer. You have to manually select the printer model for the driver, but everything prints as it should.

If that doesn't work, follow the manual instructions from http://linux.wikia.com/wiki/Getting_Canon_PIXMA_to_work_on_Linux:

$ cnijnetprn --search auto
<...Wait for system search...>
network cnijnet:/00-1E-8F-B6-E0-1A "Canon MX860 series" "Canon-MX860-series_00-1E-8F-B6-E0-1A"

$ locate mx860.ppd
/usr/share/cups/model/cnmx860.ppd
/usr/share/ppd/cnmx860.ppd
$ sudo /usr/sbin/lpadmin -p CanonMX860 -m cnmx860.ppd -v cnijnet:/00-1E-8F-B6-E0-1A -E

the -p option specifies printer name, the -m option specified ppd file. The ppd file for your printer should be included in your binary driver package and at this point should have been installed in /usr/share/ppd. The -v option specifies device uri (copy it from cnijnetprn's output).

Scanning

For scanning, edit /etc/sane.d/pixma.conf and add the line bjnp://10.0.0.20 (the Pixma's IP address). List the devices to make sure Ubuntu can find it with

$ scanimage -L
device `pixma:MX860_10.0.0.20' is a CANON Canon PIXMA MX860 multi-Function peripheral

You can additionally edit out unnecessary backends (all but pixma) from /etc/sane.d/dll.conf. That should speed the discovery up a bit. For more details, check out man sane-pixma.

Although I couldn't find any documentation as to why or how, the Canon network printer discovery protocol doesn't work right in 11.10 as it does in previous versions – perhaps a discovery timeout issue. Still, everything is up and running now.


Go to:

http://support.brother.com/g/b/downloadlist.aspx?c=us&lang=en&prod=hll2360dw_us&os=128

Download this files after agree to EULA.:

http://support.brother.com/g/b/downloadend.aspx?c=us&lang=en&prod=hll2360dw_us&os=128&dlid=dlf101123_000&flang=4&type3=10032

http://support.brother.com/g/b/downloadend.aspx?c=us&lang=en&prod=hll2360dw_us&os=128&dlid=dlf101125_000&flang=4&type3=10033

How to Install:

Turn on the printer and connect the usb, network or parallel cable.

Open a terminal. CtrlAltT.

Run it:

   sudo -i

Go to the directory where the drivers are and install the drivers.

   cd /home/user/Downloads
   dpkg -i --force-all  brgenml1lpr-3.1.0-1.i386.deb
   dpkg -i --force-all  brgenml1cupswrapper-3.1.0-1.i386.deb

Check the configuration filename.

   cat /etc/printcap

For USB Connection (Default)

The parameter of ":lp" is:

:lp=/dev/usb/lp0

Open a web browser.

Go to:

http://localhost:631/printers.

Check if the Device URI of your printer is

usb://Brother/HL-L2360DW


Sensor data missing in Ubuntu 14.04 on GA970A-D3P board

The package responsible for detecting sensors in 14.04 is libsensors4 which is developed together with lm-sensors and sensors-detect. People there are really trying hard to keep pace with new hardware integration but this will not always include all possible sensors out there.

From an overview of supported devices we have the impression that the AMD 'Vishera' processors were not yet included. Nevertheless it may be worth to try a nupgrade both libsensors, and sensors-detect to the most recent version if running on newer hardware.

There is no guarantee that sensors of a specifc device will be detected thenafter. We can not test this here for obvious reasons.

Also note that updating the package included in Ubuntu may need considerable time to include newer upstream releases. At the time of writing the upstream stable version is a 3.4.0 (released 4 days ago) whereas the version from 14.04 still is a 3.3.4.


Where to set up Workspaces & 10.04 Look & Feel?

If you go to the Software Center and search for Appearance

This will install the Appearance icon you are looking for.

As far as look and feel of 10.04... I haven't got a clue!


It sounds like you're trying to install the "cgi" gem. It ships with Ruby, so there's no need for that step. Just "require"-ing it should be sufficient.


how to play audio from A2DP enabled headset? I have ubuntu 11.10 system

I use a Nokia BH-503 headset. Please also see this post https://askubuntu.com/a/147115/37991 if you get any latency or audio breaks.


How to select and copy content from the terminal (ATL + CTRL + F1)

You could just redirect the output to a file with > or &>... I was asked to move it from comments to answers, so here it is.

By the way, a couple notes:

Putting > in between a command and a filename will overwrite the current contents of the file with standard out.

Putting >> appends to a file.

Putting a & before the redirector will also catch standard error (in Bash > 4).


What graphical utility can I use for Ubuntu auto shutdown?

GShutdown is a utility which allows you to schedule the shutdown or restart of your computer. With it you can simply and quickly choose the turn off time at either a specific time or after a countdown.
Install Gshutdown:
sudo apt-get install gshutdown

source.


CA root install issue on Ubuntu 16.04 LTS Server

1st of all thank you all you,

My issue is:
The CA Certificate which is installing in CentOS successfully, same Certificate is not installing in Ubuntu 16 Server, giving below warning message.

WARNING: CA_50EA.pem does not contain a certificate or CRL: skipping 152 added, 0 removed; done.

Solution:
After doing different approaches, unable to identify the exact root cause of this issue.
Suddenly strike one idea, this resolved my issue.

Created new root CA from the CA.pfx file using below URL steps and it successfully installed in Ubuntu 16 Server without any warnings and verified my client requests successfully.

https://www.itsupportmiami.com/how-to-convert-a-pfx-to-a-seperate-key-crt-file/

Thank you all of you, who watched my query and tried to answer.


Gnome backgroud log in, not change(after change it)

It should be fine (I think I did use a JPG a while ago), however a few notes:

If you want it to fill the display (unless you are modifying the CSS further), you will need to make the image the same size as the usual display resolution to work properly (unless you want it to tile multiple copies)
If you make copies of the files you have added/modified, this will  make it easier
For 3.16+, its fairly complicated (see here and here:)

  Note: Since GNOME 3.16, GNOME Shell themes are now stored binary
  files (gresource).

  Firstly, you need to extract the existing GNOME Shell theme to a
  folder in your home directory. You can do this using the following
  script (extractgst.sh)

#!/bin/sh

workdir=${HOME}/shell-theme
if [ ! -d ${workdir}/theme ]; then
  mkdir -p ${workdir}/theme
fi
gst=/usr/share/gnome-shell/gnome-shell-theme.gresource

for r in `gresource list $gst`; do
        gresource extract $gst $r >$workdir${r/#\/org\/gnome\/shell/}
done

  Navigate to the created directory. You should find that the theme
  files have been extracted to it. Now copy your preferred background
  image to this directory.

  Next, you need to create a file gnome-shell-theme.gresource.xml in
  the directory with the following content:

<?xml version="1.0" encoding="UTF-8"?>
<gresources>
  <gresource prefix="/org/gnome/shell/theme">
    <file>calendar-arrow-left.svg</file>
    <file>calendar-arrow-right.svg</file>
    <file>calendar-today.svg</file>
    <file>checkbox-focused.svg</file>
    <file>checkbox-off-focused.svg</file>
    <file>checkbox-off.svg</file>
    <file>checkbox.svg</file>
    <file>close-window.svg</file>
    <file>close.svg</file>
    <file>corner-ripple-ltr.png</file>
    <file>corner-ripple-rtl.png</file>
    <file>dash-placeholder.svg</file>
    <file>filter-selected-ltr.svg</file>
    <file>filter-selected-rtl.svg</file>
    <file>gnome-shell.css</file>
    <file>gnome-shell-high-contrast.css</file>
    <file>logged-in-indicator.svg</file>
    <file>filename</file>
    <file>more-results.svg</file>
    <file>no-events.svg</file>
    <file>no-notifications.svg</file>
    <file>noise-texture.png</file>
    <file>page-indicator-active.svg</file>
    <file>page-indicator-inactive.svg</file>
    <file>page-indicator-checked.svg</file>
    <file>page-indicator-hover.svg</file>
    <file>process-working.svg</file>
    <file>running-indicator.svg</file>
    <file>source-button-border.svg</file>
    <file>summary-counter.svg</file>
    <file>toggle-off-us.svg</file>
    <file>toggle-off-intl.svg</file>
    <file>toggle-on-us.svg</file>
    <file>toggle-on-intl.svg</file>
    <file>ws-switch-arrow-up.png</file>
    <file>ws-switch-arrow-down.png</file>
  </gresource>
</gresources>

  Replace filename with the filename of your background image.

  Now, open the gnome-shell.css file in the directory and change the #lockDialogGroup definition as follows:

#lockDialogGroup {
  background: #2e3436 url(filename);
  background-size: [WIDTH]px [HEIGHT]px;
  background-repeat: no-repeat;
}

  Set background-size to the resolution that GDM uses, this might not
  necessarily be the resolution of the image. Again, set filename to be the name of the background image.

  Finally, compile the theme using the following command:

$ glib-compile-resources gnome-shell-theme.gresource.xml

  Then copy the resulting gnome-shell-theme.gresource file to the
  /usr/share/gnome-shell directory.

  Restart GDM - you should find that it is using your preferred
  background image


Running Spotify or Discord causes Ubuntu 17.10 to log me out

I haven't tried those apps in 17.10, but you can switch back to the old Xorg server at the login screen by clicking the gear icon next to the sign in button:

https://itsfoss.com/switch-xorg-wayland/


The solution was given by DK Bose in the comments. Some of my config files were owned by root, not by me. In my case, I could find these files by

find .  -path "./extern/*" -prune -o ! -user $USER -ls

where the first part of the command excludes my external drive ./extern from the search.

After changing the owner and group of ~/.config/mimeapps.list (and all other files in ~/.config) I could successfully change the file associations in the system settings.


In Sublime Text 3 build systems cmd has a different syntax: you should write each argument of command in different quotes, like this:

"cmd": ["gnome-terminal", "-e", "'bash -e ...'"]

It's easier to use shell_cmd.

"shell_cmd": "gnome-terminal -- bash -c 'Your command here'"

For example, this will execute your compiled program and wait for any key to be pressed:

"shell_cmd": "gnome-terminal -- bash -c '${file_path}/${file_base_name}; read -sn 1'"


How to install latest Gnome Calendar on 16.04?

Try the one from Zesty, (17.04) on the page below. 17.04 isn't that different from 16.04, just not a long term release. You'll probably not want to add the repository, which would try to update every other program as well, so you'll probably want to download the .deb package and install with something like Gdebi package installer. It will check for dependencies and/or conflicts and won't install if those can't be resolved. I've done this with other programs.
https://www.ubuntuupdates.org/package/core/zesty/main/updates/gnome-calendar


You might try IsoBuster, which is supposed to run on Linux with Wine. I have no idea whether it is likely to actually work or not in this case.


On Kubuntu 18.04, happened the equivalent of your problem.
This because in /etc/fstab is a partition that could not be mounted.
Verify and then correct your fstab and maybe the problem will be fixed.


just check whether your disk is full.
using
df -h

if it is above 70% try to delete the content in your system.
if your GUI is not responding try through alt+f6


Rabbitvcs Nautilus not working on ubuntu 13.04

I added the below symlinks

sudo ln -sf /usr/lib/i386-linux-gnu/libpython2.7.so.1 /usr/lib/libpython2.7.so.1

sudo ln -sf /usr/lib/libpython2.7.so.1 /usr/lib/libpython2.7.so.1.0

and replaced the /usr/share/nautilus-python/extensions/RabbitVCS.py with RabbitVCS.py

Now its working fine for me. :)


Exists in QML Webkit

http://qt-project.org/doc/qt-5/qtwebkit-index.html

Most do not know if it works on Ubuntu SDK (Ubuntu Touch)


After setting to install the bundle file, it prompted me to accept the agreement

Thanks for the response.

But this will help in reading the agreement after there is no option to proceed with the process. so I added the command to this

command:

sudo ./VMware-Horizon-Client-5.3.0-15208949.x64.bundle --eulas-agreed


Machine freezes after a period of inactivity

"Fix Ubuntu 10.10 Suspend/Hibernate Not Working Bug" - http://thecodecentral.com/2011/01/18/fix-ubuntu-10-10-suspendhibernate-not-working-bug

If you read the comments it works for some people on 11.04


Getting HP Envy touch display to work a bit better

Turns out the problem was specific to XFCE installed under Ubuntu; now that I've switched back to Unity, there no longer seems to be any problem.
Still not sure what it was or how to fix it, but it now no longer applies to me.


What is the Unity HUD and how can I install it on my system?

If you are running 12.04, you already have the HUD. Just tap Alt. The HUD is not available for 11.10.


How do I prevent Application Launcher pop-up when Win-key is pressed in KDE?

The accepted answer here helped me:
https://superuser.com/questions/1156130/kde-disable-super-l-windows-key-key-shortcut-as-menu-luncher
In short:
Put
[ModifierOnlyShortcuts]
Meta=

in ~/.config/kwinrc
Logout and login. After that the Windows key only switched the keyboard layout. The Application Launcher didn't pop-up.


I've only just noticed that there's a raft of python-pyside packages in the repos. Currently version 1.1.2 (the same as their latest PPA version for Precise).

$ apt-cache search ^python3?-pyside
python-pyside - Python bindings for Qt4 (big metapackage)
python-pyside.phonon - Qt 4 Phonon module - Python bindings
python-pyside.qtcore - Qt 4 core module - Python bindings
python-pyside.qtdeclarative - Qt 4 Declarative module - Python bindings
python-pyside.qtgui - Qt 4 GUI module - Python bindings
python-pyside.qthelp - Qt 4 help module - Python bindings
python-pyside.qtnetwork - Qt 4 network module - Python bindings
python-pyside.qtopengl - Qt 4 OpenGL module - Python bindings
python-pyside.qtscript - Qt 4 script module - Python bindings
python-pyside.qtsql - Qt 4 SQL module - Python bindings
python-pyside.qtsvg - Qt 4 SVG module - Python bindings
python-pyside.qttest - Qt 4 test module - Python bindings
python-pyside.qtuitools - Qt 4 UI tools module - Python bindings
python-pyside.qtwebkit - Qt 4 WebKit module - Python bindings
python-pyside.qtxml - Qt 4 XML module - Python bindings
python3-pyside - Python3 bindings for Qt4 (big metapackage)
python3-pyside.phonon - Qt 4 Phonon module - Python3 bindings
python3-pyside.qtcore - Qt 4 core module - Python3 bindings
python3-pyside.qtdeclarative - Qt 4 Declarative module - Python3 bindings
python3-pyside.qtgui - Qt 4 GUI module - Python3 bindings
python3-pyside.qthelp - Qt 4 help module - Python3 bindings
python3-pyside.qtnetwork - Qt 4 network module - Python3 bindings
python3-pyside.qtopengl - Qt 4 OpenGL module - Python3 bindings
python3-pyside.qtscript - Qt 4 script module - Python3 bindings
python3-pyside.qtsql - Qt 4 SQL module - Python3 bindings
python3-pyside.qtsvg - Qt 4 SVG module - Python3 bindings
python3-pyside.qttest - Qt 4 test module - Python3 bindings
python3-pyside.qtuitools - Qt 4 UI tools module - Python3 bindings
python3-pyside.qtwebkit - Qt 4 WebKit module - Python3 bindings
python3-pyside.qtxml - Qt 4 XML module - Python3 bindings

Regarding the installation issues, if you have extra repositories installed, they may be borking up the process. Make sure your apt-cache policy python-pyside looks vaguely like the following:

python-pyside:
  Installed: (none)
  Candidate: 1.1.2-1ubuntu1
  Version table:
     1.1.2-1ubuntu1 0
        500 http://archive.ubuntu.com/ubuntu/ raring/universe amd64 Packages

If you have extra sources and they're providing the candidate and they don't work, that'll break installation.


virtualbox not recognising existing machine in ubuntu 14.04 LTS

Recompile virtualbox

Open terminal

'sudo -s'

hit enter

authenticate

'/etc/init.d/vboxdrv setup'

hit enter


Wireless Atheros AR5B97 not shown in lspci

I think Virtualbox hides your real network adapters from Ubuntu. It routes your active network connection to Ethernet controller: Intel Corporation 82540EM Gigabit Ethernet Controller by default (the VM network settings should be configured as NAT)


Can a version update (from 12.04 to 12.10) give driver problems?

I've been updating Ubuntu from 10.10 since 12.04. My experience with drivers is mixed. Some upgrades solved problems (example: touchpad clicks started working properly after upgrading to 11.04), other upgrades caused problems I had fixed (especially with wifi) to start causing problems again.

I would try a liveUSB before upgrading. Also most problems are solved during the first month or two of a final release. 12.10 is not yet final; it's likely there are still bugs. If you want to reduce chances of having upgrading problems, wait until the end of the year or end of January before upgrading.


/bin/false is a simple program which does nothing, and returns a status code indicating failure. you can still use it. It's a part of coreutils package so it's available by default.

"guest" line is related to Ubuntu guest user and does not have any harm or any spacial permissions to do anything to your system, it's a normal user which has access to bash however it can do nothing and all it's data are temporary.

about "postgres", it might need a bash to do a specific task.


You can use the application FolderSync Lite and a UbuntuOne account to sync one or more folders between a Ubuntu machine and your Android device.

The application allows syncing either way, or two-way, and does work for entire folders.
The application also supports many other cloud services, like Dropbox and Box.net.


How do I preseed encrypting just the root partition?

At first, open a root terminal:

sudo -i

Then fill the partition, which should be encrypted, with random data using a command like this:

openssl enc -aes-256-ctr -pass pass:"$(dd if=/dev/urandom bs=128 count=1 2>/dev/null | base64)" -nosalt < /dev/zero > /dev/sdxy

You have to replace sdxy with the partition which will be encrypted. Then type

cryptsetup luksFormat --cipher twofish-xts-plain64 --key-size 512 --hash sha512 --iter-time 2000 /dev/sdxy

to encrypt the partition sdxy. Open the volume and name it root:

cryptsetup luksOpen /dev/sdxy root

Use this command to make an ext4 filesystem inside it:

mkfs.ext4 /dev/mapper/root

Next you can start the installer. Chose "Something else" when being asked what you would like to do. Then chose the mount points for all your not-encrypted partitions. For your root partition, select /dev/mapper/root, click "Change". Then select ext4 for the filesystem type and set the mount point to /. Then click "Install now" and install Ubuntu normally.

When finished installing click "Continue testing". Open a terminal and type:

sudo -i
cd /mnt
mkdir root
mount /dev/mapper/root root
mount /dev/sdyz root/boot

sdyz should be replaced with your boot partition. Next, type:

chroot root
mount -t proc proc /proc
mount -t sysfs sys /sys
nano /etc/crypttab

Open a second terminal and type sudo blkid. Find the UUID for root (the one that says crypto_luks in the end) and paste it into /etc/crypttab. Then the file /etc/crypttab should look something like this:

root UUID=d68911dd-172a-4608-86d4-084eb72f409c none luks

Close the file with Ctrl+x, y and Enter. Type nano /etc/fstab in the terminal and check if everything looks right (e.g. the UUIDs).

At last, quit the chroot environment and type:

cryptsetup luksHeaderBackup /dev/sdxy --header-backup-file /root/root.img

This puts an image of the header of the encrypted partition into the folder /root and names it root.img. Then move the image to an external drive (in case of forgetting the password). Now you can reboot into your newly installed Ubuntu.

Source: http://thesimplecomputer.info/full-disk-encryption-with-ubuntu


How do I move one directory to another in Ubuntu

GUI Method:

Open file manager, eg Nautilus
Right click on the folder and click on Cut
Go to desired folder
Right click and choose Paste

CLI method: Open Terminal and run:

mv <absolute path of folder to be moved> <absolute path of destination folder>

For example:

mv menu data


you should enter example.com to your /etc/hosts file and reload apache. You should also enable the virtual host with sudo a2ensite.

So:

Add NameVirtualHost *:80 to you apache configuration. I add this in top of default in /etc/apache2/sites-available
Create a virtual host configuration file say example in /etc/apache2/sites-available
Enable it with sudo a2ensite example
Enter your ServerName to your /etc/hosts mapping it to 127.0.0.1
Restart/Reload apache2 with sudo service apache2 restart/reload

I think that ServerAlias is not that necessary


find Noise level iwlist and iwconfig commands

There is another question similar to this. It looks like this is because of driver capabilities

https://stackoverflow.com/questions/11232433/iwconfig-does-not-show-noise-level-for-wireless


The problem was in my code. if statement was if(ret <= 0) and it was conflict with the libusb_init

So that's it. The working source code is written below.

# include<stdio.h>
# include<stdlib.h>
# include<usb.h>
# include<libusb-1.0/libusb.h>

int main(int argc, char *argv[]){

    libusb_device **devs;
    libusb_context *context = NULL;

    size_t list;
    size_t i;
    int ret;

    ret = libusb_init(&context);

    if(ret < 0){
        perror("libusb_init");
        exit(1);
    }

    list = libusb_get_device_list(context,&devs);

    if(list < 0){
        fprintf(stderr, "error shuu\n");
        libusb_free_device_list(devs,1);
        libusb_exit(context);
        exit(1);
    }

    int listp = list;

    printf("end %d toxooromj bn\n", listp);

    for(i=0;i<list;i++){
        //print something
    }

    libusb_free_device_list(devs,1);
        libusb_exit(context);

    return 0;
}

A special thanks go to @Kulfy for telling me reconsider about check the source code again.


Run this:

sudoedit /usr/share/polkit-1/actions/org.freedesktop.upower.policy

Change action id="org.freedesktop.upower.hibernate">defaults>allow_active to no. Save and exit. That will stop users being able to do that from the desktop.

If you have a sleep or hibernate button on your keyboard or case, these will still work IIRC so you need to "break" their default behaviour. Run:

gconftool -s /apps/gnome-power-manager/buttons/hibernate -t string interactive

Source.


How to get list of apps installed using sudo apt-get install?

as the apt-man --help states

showmanual - Print the list of manually installed packages

  apt-mark showmanual

So, it should just give a list of explicitly installed packages without all of the dependencies included due to these packages being installed.


Database not working on actual Ubuntu Touch Device

Finally solved my problem... all I have to do is to make sure the name property of my mainView is the same as the name field in my manifest file.

That's it...thanks for those who considered answering my question :)


How do you turn off subtitles in VLC for a video started from terminal?

You can try --no-sub-autodetect-file option.


For Ubuntu Mate...
Your /etc/network/interfaces should look like this...
# interfaces(5) file used by ifup(8) and ifdown(8)
auto lo
iface lo inet loopback

Your ONLY /etc/netplan/*.yaml file should look like this...
network:
  version: 2
  renderer: NetworkManager

Create this file... /etc/cloud/cloud.cfg.d/99-disable-network-config.cfg with the following content...
network: {config: disabled}

sudo netplan generate
sudo netplan apply
reboot
Then use the NetworkManager GUI to configure your eth0 wired connection for a static IP (if that's what you want/need)...


I had an issue like this that was being caused by interference with Jack (jackd) on 13.04.  I never had the issue on 12.10.  I removed Jack and Ardour and all worked perfectly.  sudo apt-get remove --purge jack ardour jackd

If you don't have Jack installed, consider any other packages that might be holding your sound card hostage.

Try running aplay -l without the sudo and see if that helps with your permission error.  Occasionally I've seen root get denied access to folders in a user's home (which to my understanding shouldn't happen, but I've seen it).


Snaps suddenly missing from Launcher and PATH

You're hitting this snap bug:

https://bugs.launchpad.net/ubuntu/+source/snapd/+bug/1640514

A workaround is to explicitly source /etc/profile.d/apps-bin-path.sh in your .zshrc or .zshenv.


Cron runs command but it has no effect. How to fix?

What do you expect the "~"  in ~/project/storage does? 1 thing I can guarantee you is that it will NOT expand to /home/$USER/.

Solution: always use explicit (/absolute) paths when you use any of the crons.

And regarding your method a tip: I would never do it like this. If I was you I would create a compressed tar file with a timestamp first, then remove the files and store the compressed tar file in a different directory and remove those tar files after a grace period (like a week or a month or even after a year). I can not tell you how often that method saved my skin in the past 25 years. If even to solve a question from a client asking what happened with some action they did.


How to open a file in the same display I am working it?

The behaviour you describe (opening the window on the current screen) should be the default behaviour, On my 14.04 it is like that.

Due to minor incompatibilities with some graphics driver/GPU combinations, "peculiarities" might occur in some cases. If there is no "clean" option available (fix), you can use the workaround below.
It exists of a background script, looking for new windows to appear. In case a new window exists, the script compares the window position to the current mouse position. If both the mouse and the new window are not on the same screen, the window is moved, using the xdotool windowmove` command.

Is a background script a bad idea?

If you do not need a background script, don't use it.
At the same time: if it adds important functionality and/or saves you time, It would be silly not to, if the script is well organized and therefore "low on fuel".

As a reference: on both my laptop and my Desktop, I constantly run at least 5 background scripts + occasionally some additional ones for testing purposes, without any notice.

What is done to save fuel:

The script has a variable loop cycle
Once per 10 seconds, the script checks for the second screen to be connected. If not, the script skips the whole window check- procedure and re- checks after 10 seconds. This means that the script only acts if a second screen is attached. Once a second screen is connected, within 10 seconds, the loop is changed to a period of 2 seconds.
All (next) actions the script takes are conditional
e.g. the mouse position is only checked if there are new windows etc.

All together, on my system I could not notice nor measure any additional load, as a result of the script.

The script

#!/usr/bin/env python3
import subprocess
import time

def get(cmd):
    try:
        return subprocess.check_output(cmd).decode("utf-8").strip()
    except subprocess.CalledProcessError:
        pass

def screen_limit():
    screendata = [s for s in get("xrandr").split() if s.count("+") == 2]
    if len(screendata) == 2:
        return int([s.split("x")[0] for s in screendata if "+0+0" in s][0])

wd1 = get(["wmctrl", "-lG"])

t = 0
while True:
    time.sleep(2)
    # once per 10 seconds, check for a second screen
    if t == 0:
        while True:
            rightside = screen_limit()
            # if no second screen, skip the procedure
            if rightside == None:
                time.sleep(10)
            else:
                break
    wd2 = get(["wmctrl", "-lG"])
    # check for buggy wmctrl
    if all([wd2 != None, wd1 != None]):
        wins = [w.split() for w in wd2.splitlines()]
        # check for new windows
        relevant = [w for w in wins if not w[0] in wd1]
        if relevant:
            # if new windows appeared, see if they match the mouse pos
            mousepos = int(get([
                "xdotool", "getmouselocation"
                ]).split()[0].split(":")[1])
            for w in relevant:
                check = [mousepos < rightside, int(w[2]) < rightside]
                if check[0] != check[1]:
                    # if mouse and window are not on the same screen > move
                    if check[0] == False:
                        cmd = ["xdotool", "windowmove", w[0],
                            str(int(w[2]) + rightside), w[3]]
                    else:
                        cmd = ["xdotool", "windowmove", w[0],
                            str(int(w[2]) - rightside), w[3]]
                    subprocess.Popen(cmd)
    wd1 = wd2
    t = 0 if t == 10 else t
    t += 1

How to use

The script needs both wmctrl and xdotool. Run in a terminal:

sudo apt-get install xdotool wmctrl

Copy the script into an empty file, save it as move_windows.py
Test- run the script by the command:

python3 /path/to/move_windows.py

If all works as expected, add it to Startup Applications: Dash > Startup Applications > Add. Add the command:

/bin/bash -c "sleep 15 && python3 /path/to/move_windows.py"


You could create an extra file: /etc/proftpd/conf.d/printftp.conf with following configuration:

Umask                002  002
RequireValidShell    off
DefaultRoot          ~
UseReverseDNS        off

<IfModule mod_cap.c>
  CapabilitiesEngine off
</IfModule>

<Directory /var/www/print.example.com/www/>
  UserOwner   www-data
  GroupOwner  www-data
</Directory>

First part is the umask for your permissions, and second part is for setting the permissions. It's possible you need to tweak the config according to your needs.


Dualboot Ubuntu to VirtualBox VDI migration

Have you tried copying the contents of your boot directory to /boot on the root of the drive you want to boot from?

This will copy the various kernels and other files grub may need.

Then try and install grub with grub-install again.


time-out while trying to download public keys

Most probably the port (11371) used for downloading the GPG key from the Ubuntu keyserver is blocked by your ISP/firewall. Unfortunately all the alternate keyservers use the same port.

Hopefully keyserver.ubuntu.com will start using a standard port for this in the future...


Tethering's not running in ubuntu-touch, how to solve it?

There is a mako-specific bug (mako: Nexus 4) right now which needs to be fixed. It seems you are affected by this bug. https://bugs.launchpad.net/ubuntu/+source/dbus-property-service/+bug/1427697


The look and shape of the buttons on the title bar is determined by the GTK theme that you are using. Themes can be changed in Gnome Tweaks, Appearance tab. That utility is not installed by default. The default theme in Ubuntu is Yaru. The list of themes available depends on the themes that are installed on your system. Some additional themes can be installed using synaptic package manager or the terminal. Third party themes are available at sites like Gnome Look.
You can only change themes at once. Unfortunately, in Gnome, which Ubuntu uses in its default desktop, there is no user exposed granular control to change individual aspects of the desktop appearance. Any such changes would require to manually edit or changing icon files or edit style code.


How do I upgrade releases from a Live USB with the command line?

Sure. It's fairly similar to most remote-fixes (namely fixing Grub) where you chroot into the system but mount some the runtime elements from the Live environment over the top. It's quite easy but it sounds and looks horrific if you're not used to it!

The following assumes that / is the live environment and that sdb1 is the disk where the actual install is (check that first with sudo fdisk -l!). Other than that, it's just a pile of commands to throw in:

sudo mount /dev/sdb1 /mnt
for i in /sys /proc /run /dev; do sudo mount --bind "$i" "/mnt$i"; done
sudo chroot /mnt

By this point you're root on your actual system and you can fix a whole load of things. Obviously this is the point where you need to be careful what you do but as long as you're not running around rming a load of stuff, you'll probably be fine.

You probably could run the graphical updater but why muddy the waters with silly Xauth issues? The following will update your install's apt databases, download the command-line updater (if it's not installed already) and run it. You're already root so sudo isn't necessary but I'm including it just in case you've dropped to another user (it doesn't hurt)

sudo apt-get update
sudo apt-get install ubuntu-release-upgrader-core
sudo do-release-upgrade

When you're done, just reboot onto your main disk.


/run/network/ifstate keeps getting reset on reboot

/run/ is a tmpfs file system that only exists in RAM and is created anew on every system start. Any changes you make there are lost after shutdown.

To prevent Networkmanager to automatically connect to that hostspot edit the connection and switch off the "Automatically connect to this network when it is available" option.


The Apache Ubuntu page is placed in your webroot (/var/www/html) when you install Apache. This was not removed when you removed Apache, as files in your  webroot are not necessarily directly related to Apache, and should be deleted manually if desired. When you installed Nginx, it placed its default file under the name of something like index.nginx-debian.html. When you requested the page, the server searched for an index (more info here), and found the one from Apache (index.html) before the one put there by Nginx. To fix this (though it is not really a problem per say), run the command

sudo rm /var/www/html/index.html

To delete the file from Apache.


I did some googling and found a program called AutoKey (Autokey - Linux utility for text substitution hotkeys) near the top of the list.

Rather than a hotkey using Ctrl+Shift+K I chose to assign the abbreviation kz which is automatically expanded into <kbd></kbd>+.

It is simply installed using:

sudo apt install autokey-gtk

It installs in Launcher and the screen is pretty simple to use:


automatic system updates , how to configure APT::Periodic::AutocleanInterval to clean obsoleted cache only?

If you don't know what you are doing don't use commandline. Use GUIs like synaptic. There are a lot of options to configure how Ubuntu should treat available update. To start it just press Alt+F2 and when dialog appears type command

gksudo synaptic

fill in password and when synaptic opens go to
settings->repository
see the updates tab and select options as per your flavor


Linux commands to use Windows bootloader instead of Grub

Try this command

sudo gedit /etc/default/grub

and change the GRUB_DEFAULT to what windows boot loader is.


no way to use opendns on pppoe connection?

If you are using NetworkManager then you should use the Connection Editor to adjust network settings. To set your own nameserver addresses, click on the network indicator | Edit Connections...; select your connection; open the "IPv4 Settings" tab; change "Automatic (DHCP)" to "Automatic (DHCP) addresses only"; enter the desired nameserver addresses in the "Additional DNS servers" field.


I first tried to remove and reinstall ssh but it didn't work for me then I tried to purge it:

sudo apt-get purge openssh-server
sudo apt-get install openssh-server

so now its working.


Removed Wubi from Add/remove programs menu, but I can still boot into it

If you have attempted to uninstall Wubi but Ubuntu is still there, try "Uninstall-Ubuntu.exe" from the Ubuntu Wiki:

https://wiki.ubuntu.com/WubiGuide?action=AttachFile&do=view&target=Uninstall-Ubuntu.exe


Trying to start CUPS service on a Chromebook running Ubuntu 14.04 via crouton

WIP: (answered half of the question)

  I would also like to know how to properly add the /usr/sbin/cupsd command to /etc/rc.local.

a. Open gedit and paste the following (ignore "):

  "#!/bin/sh -e

  sudo /usr/sbin/cupsd

  exit 0"

b. Save the file as anyname.sh to /path/to/your/directory (its best to keep the path in your home directory:)

c. Now, open terminal and type:

sudo gedit /etc/rc.local

d. Add the following line before exit 0.

  sudo sh /path/to/your/directory/anyname.sh


No sound from headphones on Samsung Series 7 Chronos ( NP700Z5a )

Installing the ALSA/DKMS package for Intel sound cards fixed this


How to update Python 3.5.2 shell (IDLE) to the latest version 3.7.3?

Similarly to your Python installations being seperately accessible by python3.5 and python3.7 (while python3 and python are only symlinks that point to one of those), you should have idle3.5 and idle3.7 available in your path, with idle pointing to the first.

If this doesn't solve your problem, please be more specific on what you tried, how you installed Python, and what you expect.


Ubuntu uses logrotate

You configure it in /etc/logrotate.d

Sample syntax:

   /var/log/messages {
       rotate 5
       weekly
       postrotate
           /usr/bin/killall -HUP syslogd
       endscript
   }

for full configuration options see:

http://manpages.ubuntu.com/manpages/precise/man8/logrotate.8.html

http://articles.slicehost.com/2010/6/30/understanding-logrotate-on-ubuntu-part-1

http://articles.slicehost.com/2010/6/30/understanding-logrotate-on-ubuntu-part-2


Lightning 1.8 in Thunderbird 16.0.2 doesn't work under Ubuntu 12.10

Install the xul-ext-lightning package.  The version from addons.mozilla.org won't work with amd64 systems.


According to this post on the UbuntuForums "initramfs) unable to find a medium containing a live file system.", you should try this:

  Change the SATA controller type from IDE to AHCI in Bios and everything works perfectly


xsetup is not the Ubuntu command to use to uninstall a package, but instead is in this case a script for installation of Vivado only.

First, confirm the exact package name by reviewing what's installed with dpkg --list .

Then, do sudo apt remove “package-name” or  sudo apt purge “package-name”. The latter removes any personalizations.

sudo apt autoremove if run subsequently removes dependencies.

You may also be able to use a package manager, such as Synaptic, to remove and purge.