After you run chmod +x your shell script became executable. Now you can run it

./ts3client_runscript.sh

from the directory script lives in. Its a bit tricky, don't forget to put ./ in front of shell script file name.


How can I limit the GUI choices in the drop-down menu at login?

Yes, you can do this. Just move the undesired session files from the directory /usr/share/xsessions to another directory.

The quick way to do so is, typing gksu nautilus in the dash prompt ( pressing Alt-F2 ) and hit Enter. It will open nautilus with root power. Go to the /usr/share/xsessions folder and remove or move the appropriate file in another directory.

You can open those files to determine which file actually needs moving. Use gedit to open them. For example, you may want to remove "Gnome / Openbox" or "KDE / Openbox" files to another dir.


Is there any way to add more spaces to Ubuntu Drive (where the home is)?

Are you wanting to change your partition sizes (say shrinking your / partition then growing your /home partition)?

If so use gparted, which you can install by running:

sudo apt-get install gparted && gksudo gparted

If you are wanting to add another hard disk and move your data from /home to this drive, it's about the same.

In gparted highlight the partition you wish to move and select copy, then select the disk you wish to move the partition to and paste it.

Then grow the partition to fill the rest of the drive and execute (I think it's called run, looks like an enter symbol)


you can also do it from Ubuntu tweak tool.
install it from

sudo add-apt-repository ppa:tualatrix/ppa

sudo apt-get update
sudo apt-get install ubuntu-tweak

Then open ubuntu-tweak and there at Themes you can reset icons to original.


Getting rid of irritating dead battery notification

Did you try taking out the battery? This may prevent it from being detected, and stop the notification appearing.


First you have to shrink the LVM volume

Read this to learn how. you can either use the answer marked or use gparted with version > 0.14.

One you shrink the LVM you can know create a new partition for swap using Gparted.

Now it's time to add this newly create parition to fstab

You need to edit /etc/fstab and add the new swap partition.

sudo gedit /etc/fstab

You need to add a line that looks like

UUID=new-partition-UUID none   swap    sw      0       0

You can get the UUID using the command

sudo blkid /dev/sdaX

Where sdaX stands for the newly created partition

Another workaround is to create a swap file instead of a swap partition.

in this i'm going to create a 4G swap file

sudo fallocate -l 4G /swapfile

verify that the correct amount of space was reserved by typing:

ls -lh /swapfile

output should be

-rw-r--r-- 1 root root 4.0G Apr 28 13:19 /swapfile

To enable the swap file:

sudo chmod 600 /swapfile

Verify that the file has the correct permissions:

ls -lh /swapfile

output should be:

-rw------- 1 root root 4.0G Apr 28 17:19 /swapfile

Now teell  system to set up the swap space:

sudo mkswap /swapfile

output would be like:

Setting up swapspace version 1, size = 4194300 KiB no label, UUID=e2f1e9cf-c0a9-4ed4-b8ab-714b8a7d6944

Our file is now ready to be used as a swap space. We can enable this by typing:

sudo swapon /swapfile

We can verify that the procedure was successful by checking whether our system reports swap space now:

sudo swapon -s

output would be like:

Filename                Type        Size    Used    Priority
/swapfile               file        4194300 0       -1

source


=> / is using 95.8% of 228.23GB But I can't figure out whats taking up the space?

I umounted the backup from /mnt/backup and then checked /mnt/backup if there was any data left sure enough the 200gbs showed up. After removing that the server started right up Thanks for the help y'all :D


"readline" when there is output at beginning of line

[Stackoverflow would be a more appropriate place for such a programming question]

This is not a bug but the expected behaviour. readline is not aware of what was written on the terminal earlier and at what position it is writing. Think "basic serial terminal". Moreover other background processes (which your program is not aware of) may also write to the terminal.

So, readline assumes it starts to write at the beginning of the terminal line. When you Ctrl-U (unix-line-discard), readline goes back where it thinks you started to type characters, i.e. just after its prompt. Your prompt "OK> " is four characters long, so readline put the caret at the 5th place and erase the line, leaving just "Hell".

The workaround could be to skip a line before calling readline, or to begin your prompt with a CR character (i.e. \r), which would force the prompt at the beginning of the line, overwriting "Hello" (but a longer text would only be partially overwritten).

[update]

As for why sometimes Ctrl-U erases just the last typed characters, and sometimes it erases (almost) the whole line, it is a readline optimisation.

readline can emit two different character sequences to erase the whole input:

either: n × <BS> (backspace) + <control sequence to erase the whole line> (e.g. ANSI <ESC> [ K), where n is the number of characters typed so far.
or: <CR> + m × <control sequence to move the cursor to the right> (e.g. ANSI <ESC> [ C) + <control sequence to erase the whole line>, where m is the length of the prompt.

readline choose the shortest, which depends on the number of characters typed wrt the length of your prompt.


How to revert classic GNOME decorations for gedit, nautilus etc?

DK Bose indeed pointed to a possible duplicate: the goal there, however, was quite different, and so is the question. The answer, however, is largely the same.

Newer versions of applications started to introduce GTK3 Client Side Decorations (CSD). This means that the application itself, and not the window manager, draws its title bar and includes controls in it.

CSD cannot easily be avoided. Linux Mint adopts the approach of eliminating all CSD and has forked core gnome applications to revert to a traditional header bar and menu. The Mate desktop as well works with core gnome applications that were forked from the Gnome 2 branch. It is difficult to avoid CSD if your desktop, including standard Ubuntu, includes it. Options are:

You can avoid CSD applications, and move to the alternative applications of Linux Mint or Mate. Unfortunatelly, that indeed means uninstalling applications that "belong" to your desktop, and install and integrate alternatives (e.g. nemo instead of nautilus), in short, a need for heavy desktop customization.
The more fundamental option to avoid CSD is to move to another desktop environment that does not adopt to CSD. These include Mint Cinnamon, XFCE, Mate and KDE.

To be complete, I also should mention gtk3-nocsd. You can re-add a traditional title bar, but the CSD area beneath remains, leading to a less than pleasant appearance.


Update went wrong. Drivers messed up. Internet connection lost

Thanks to mark kirby's suggestion, I managed to fix the problem.
What I did to fix my problem :

In GRUB, I selected advanced options for Ubuntu and picked the kernel before the latest one and loaded that kernel.

I updated my packages using sudo apt-get update.

I cleaned the downloaded packages using sudo apt-get clean.

I removed unneeded packages using sudo apt-get autoremove.

I reconfigured all packages using sudo dpkg --configure -a.

I fixed broken packages using sudo apt-get install -f.

I removed the latest kernel using sudo apt-get purge linux-image-x.x.x-x-generic.

I updated my GRUB using sudo update-grub2.

I rebooted my system.

References I used for this prodecure :

An error occurred, please run package manager
How do I remove or hide old kernel versions to clean up the boot menu?


How to install an already downloaded .crx file extension in chrome?

This is a known issue.

Download the .crx file. Drag and drop the downloaded novell-moonlight-3.99.0.3-i586.crx file into Google chrome browser.

If you get any error mentioning "Apps extensions and user scripts cannot be added from this website", open chrome://chrome/extensions/ in a new tab and now repeat the step 1


Use the linux 'templates' folder to make folder templates

Have you seen the New Folder from Template extension for Nautilus?


Is there any chance to use Ubuntu with a live USB pen drive on my MacBook Pro 2018 with touchbar?

A Google Search for this problem revealed a kernel patch has been published for the Touchbar. However, patching the kernel used in a LiveUSB is highly problematic, and you would be better off installing Ubuntu into the USB as if you were installing to an SSD, from a different LiveUSB, then patching the kernel on the non-Live USB.


I am by no means an expert, however from what I know this could happen because either:

a) Your CPU does not support hardware virtualization

b) CPU does support virtualization, but you have not enabled it in BIOS.


Where are TorGuard VPN's settings stored?

After contacting support the issue has been solved.

The config file is stored in ~/.config/VPNetworkLLC/TorGuard.conf. Removing the file and restarting the app fixed the issue for me.


PgAdmin4 "the application server could not be contacted" Ubuntu 19.04

Try following the advice in this article: How to Install and Configure pgAdmin4 on Ubuntu 18.04 & 16.04
Remove the previous installation
sudo apt-get remove pgadmin4

and reinstall
sudo apt-get install wget ca-certificates
wget --quiet -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc | sudo apt-key add -
sudo sh -c 'echo "deb http://apt.postgresql.org/pub/repos/apt/ `lsb_release -cs`-pgdg main" >> /etc/apt/sources.list.d/pgdg.list'
sudo apt-get update
sudo apt-get install pgadmin4 pgadmin4-apache2

for me it worked.


Flash is obsolete now.
Run
 sudo apt purge pepperflashplugin-nonfree

to uninstall it.


Ubuntu 13.04 lenovo m490 INFO @wl_cfg80211_attach : Registered CFG80211 phy

According with this comment:

  I got the same message on startup, but I don't think it's a bug. Just it's annoying message on startup

Next:

  The same INFO message for me: I have the message each time at startup just before Ubuntu splash screen.

Is just a message, nothing to be scared of.


Dual Boot Ubuntu OS problem. D Drive lost.

It sounds like you installed ubuntu on the "d" drive partition. That means that the "d" drive uses the ext3 or ext4 file system (Linux) which cannot be accessed from within windows because it is not supported. You can still access NTFS file systems (windows) from within Linux, though.

If you have data on that drive that you need in windows then log in to your ubuntu install and copy them onto an NTFS partition so that windows can see them.


Bluetooth Heaphones connect but don't output sound [Ubuntu 20.04]

You can try installing Blueman and check if it detects your bluetooth headphones.
sudo apt install bluez bluez-tools
sudo apt install blueman

You can either run these commands or install Bluetooth Manager from your Ubuntu store.


I'm going to assume that /dev/sda6 is your currently unused 230G /home partition you want to use, based on the number of blocks. This should work:

$ cd /
$ sudo mkdir /media/home_backup
$ sudo mount /dev/sda6 /media/home_backup

# below, -rp flags indicate recursive, and keep owner/permissions

$ sudo cp -rp /home/* /media/home_backup

$ sudo umount /media/home_backup
$ sudo mv /home /home.bak
$ sudo mkdir /home
$ sudo mount /dev/sda6 /home

# the large partition should be mounted at /home now. The following
# will make sure it's mounted at boot

$ sudo umount /home

# edit /etc/fstab as sudo, and add the following to the bottom
# of the file (tab separate each entry)

/dev/sda6 /home ext4 default 0 2

# save the file and then:

$ sudo mount -a

If the last command works and you can list the /home partition, it will mount successfully at boot.


Is Drobo5N2 Dashboard available for Ubuntu 16.04?

Drobo's download page only lists the software for Mac and Windows, so seemingly there's no package available for Ubuntu or any other Linux distribution. I suggest you contact Drobo and let them know you miss a .deb package for their software, they'll listen if they care.
In the meantime you can run “Drobo Dashboard for Windows” in a virtual machine, see e.g. How to run Windows XP inside Ubuntu.


rsyncing files only if they exist in target

Type in man rsync into the terminal to see the man page. It shows you all the options available and explains them. I think what you are looking for is

--existing              skip creating new files on receiver

so use it as option

rsync --existing


Jupiter uses icons from /usr/share/pixmaps/ directory. I've looked through the source code of "Jupiter" and I've found that icon names are hard-coded in application:

def update_icon(self):
    m = self.jupiter.get_current_cpu_mode()

    if m == 'high':
        if loaded_indicator:
            self.ind.set_icon('bolt1')
        else:
            self.tray.set_from_icon_name('bolt1')
    elif m == 'powersave':
        if loaded_indicator:
            self.ind.set_icon('bolt4')
        else:
            self.tray.set_from_icon_name('bolt4')
    else:
        if loaded_indicator:
            self.ind.set_icon('bolt2')
        else:
            self.tray.set_from_icon_name('bolt2')

So you can replace the following icons with what you like:

/usr/share/pixmaps/bolt1.png
/usr/share/pixmaps/bolt2.png
/usr/share/pixmaps/bolt3.png
/usr/share/pixmaps/bolt4.png

Surely you can change source code of "jupiter" :)


I used 8.04,11.04,11.10,12.04,12.10 Versions & Now I'm using 13.04 & I found the best driver support in the last Version (13.04) & I say even its more stable than 12,04 LTS!


Command to activate (either run or bring to front if already running) a program

A little bash and xdotool should do the trick. Notes on installing xdotool at end of post.

ActivateOrLaunch.sh

#!/usr/bin/env bash

# usage:
#    ActivateOrLaunch.sh firefox-bin
#
# Will launch firefox-bin or activate the first window in the windows stack
# --- Remember to chmod a+x ActivateOrLaunch.sh in order to execute.

# pgrep looks through the currently running processes and lists the process
#       IDs which matches the selection criteria to stdout
#       for more information on pgrep http://linux.die.net/man/1/pgrep

# if process is found by pgrep then pipe through head to get firt instance in
#    case of multiple processes running. If process not found $pid will be empty
pid=$(pgrep ${1} | head -n 1)

# Using "-z" check if $pid is empty, if so execute the process
if [ -z "$pid" ]; then
   echo "$1 not running... executing..."
   $1 &
else
   # process was found, find the first visible window and activate it
   echo "Found process $1 with PID $pid"

   # using xdotool [http://www.semicomplete.com/projects/xdotool/] get the first
   # visible windows using $pid. Redirect stderr to /dev/null and only select
   # the first visible windows using head
   wid=$(xdotool search --onlyvisible --pid $pid 2>/dev/null | head -n 1)

   # if $wid is empty the process does not have any visible windows... do nothing
   if [ -z "$wid" ]; then
     echo "Didn't find any visible windows for process $1 with PID: $pid"
   else
     # send the window id ($wid) from the window stack to xdotool
     echo "Activating first windows in stack"
     xdotool windowactivate $wid
   fi
fi

# ******** NOTES **********
# In order for this script to work correctly you need to pass the complete process
# name for it to find any visible windows. The process needs needs to be in the path
# for it to execute if not running.
#
# For example
#
# If you try it with firefox-bin on Ubuntu 10.10 it will find the running process and
# activate the window, but it will not be able to launch the process since the executable
# in the path is called firefox which is a link to firefox.sh
# (/usr/bin/firefox -> ../lib/firefox-3.6.12/firefox.sh) which in turn executes firefox-bin
# (not in path).
#
# Next, if you use firefox it will find a process but won't be able to find any windows
# since it's a wrapper function calling firefox-bin and doesn't have any windows.

You can find the code on github

I tested the code on Ubuntu 10.10 (Gnome) and it worked. It need some polishing since I just typed it up and wasn't worried about making it pretty (wanted to make sure to get the comments in)

To install xdotool you can apt-get install xdotool (form me this fetched version 2.20100701.2691), if you want the latest and greatest get it from here (as of 20101116 it's as version 2.20101012.3049-4)


Can't access a local disk, links don't exist

Symlinks are like text files containing the absolute or relative path they point to as plain text. So, as the partition which used to be mounted at / is currently mounted at /media/ubuntu/YOUR_UUID_HERE, absolute symlinks break, obviously.

I'd recommend to chroot into your disk partition, so that the links work again. Chrooting changes the root directory to any directory you like, so you can get a terminal that behaves like it runs from your system on the disk after having booted from the DVD.

From the live DVD, do run these commands to prepare and enter the chroot environment:

Mount your hard disk Ubuntu partition as /mnt. You might have to unmount it from the Files manager first, as it can't be mounted twice. Replace /dev/sdXY with your partition's real identifier, e.g. /dev/sda1. Use the lsblk command to identify which one it is.

sudo mount /dev/sdXY /mnt

Bind your live system's virtual system folders to their respective locations in the target folder:

for d in /dev /dev/pts /sys /proc ; do sudo mount --bind $d /mnt$d ; done

You say you want to recover some data, so I guess you have some external storage where you want to copy the stuff to. I'll assume that storage is located at /media/ubuntu/my-backup-disk, replace with your respective path. It must be accessible from the chroot environment, so we bind it inside the target directory as well:

sudo mkdir /mnt/storage
sudo mount --bind /media/ubuntu/my-backup-disk /mnt/storage

Enter the environment.

sudo chroot /mnt

Now you are in a root shell, and the / root directory will be what was /mnt in the outer live session. It should behave like a root shell that booted from your hard disk installation.
Unlock your encrypted home like you would have done from your installation, I guess using:

ecryptfs-mount-private

Copy your important files from your home directory or wherever to your backup disk, which we have bound to /storage (it was /mnt/storage outside the chroot). This could look e.g. like below, replace with your own appropriate paths:

cp -R /home/bee/Documents /storage/Documents

Once you are done, you can leave the chrooted environment again by exiting the root shell:

exit

You are back in the normal shell of the live system.
Unmount your disk installation's partition again:

sudo umount -R /mnt

I guess you're done here. You can close the terminal and shut down the live system, or do whatever else you want.


How can I read and capture error messages that appear on the screen before login?

Executing journalctl -b "should do the trick" ... this will show the journal entries that have been collected since the most recent reboot. journalctl -b -1 shows the entries from the boot event before. Reference (and information) : How To Use Journalctl to View and Manipulate Systemd Logs

To see additional options you have with journalctl, such like journalctl -b --list-boots,
you can check them out by executing the commands journalctl --help or man journalctl.


I am the same Tor Kingdon who posted it... hadn't realized I already had an account here. Oops. In any event, the problem seemed to go away when I brought that (rather heavy) tower home and hook it up to our home internet. If it returns when I get back to the work network, I'll contact the building's network provider. Thank you to anyone who has read this. (I'll also delete my duplicate account as soon as I can figure out how to log in to it. ;))


How to remove rstudio-server-1.0.143-amd64.deb in ubuntu 16.04 linux machine

Guess here that you installed rstudio-server by downloading it from an external source and then installing it using dpkg or GDebi. So, you are trying to remove it using the command:

sudo apt-get remove rstudio-server-1.0.143-amd64.deb

But, rstudio-server-1.0.143-amd64.deb is the name of the file. The software is installed as: rstudio-server. So, the correct command will be:

sudo apt-get remove --purge rstudio-server


What are the alternatives to Notepad++ on Ubuntu?

Actually you can install Notepad++ by installing wine first:
sudo apt-get update; sudo apt-get install wine

But some good alternatives are:

Vim
Emacs
Geany
kate (in KDE, running in unity with the installation of the proper
KDE dependences)
Sublime (free, unlimited trial version/ or $70.00 US Dollars)
GEdit
Komodo Edit (in KDE)
Editra

Of these, Geany and GEdit are my favorites, but it depends on your needs. If you are looking for something more complex, there is the Aptana Studio which I mentioned in detail as an answer in this question: Basic Web Development IDE/Editor like Dreamweaver?
Good luck!


As there is a brief delay before the logs are written to disk, nothing may have been recorded, however something of general interest concerning the power management of your laptop may be found by using dmesg:

dmesg | grep -i acpi

To go back further in time and to show dates alongside the results, you could grep all the kernel logs for acpi messages:

grep -i acpi /var/log/kern*

which will give a lot of messages, but may perhaps show any issues to do with power management.


"Package operation failed" in Ubuntu Software Center

When upgrading Virtual Box to a newer major release version (e.g. from 4.x to 5.x) we need to remove the older version first to be able to proceed.

Removal of a package depends on how you had installed it. In most cases you can use the Software Center to remove installed packages. In case you had installed Virtual Box from the repositories it is the package virtualbox you will have to remove.

If a package is not listed there, or if we had installed it from another source we may also issue the following command in a terminal (for removal of virtualbox 4.0):

sudo apt-get remove virtualbox-4.0

Note that your settings and your existing virtual machines will stay untouched, they will not be removed.

After that we can safely re-install Virtual Box from a DEB file we had downloaded, or by adding the Oracle repository to our sources, which will always install the most recent version (at present 5.0.8). After upgrading Virtual Box we should also upgrade the Guest Additions in our virtual machines.


How to install and configure nova-lxd on existing openstack

This document helps you. If you decide to use nova-lxd instead of kvm on your existing openstack you must run:

apt install nova-compute-lxd

This command automatically configure your nova-compute service. Then restart it, I hope it will work successfully.


Ubuntu 20.04 LTS libusb/hidapi fails to open Corsair/Elgato Streamdeck

Issue was due to the rule I created ending with .conf instead of .rules.
... Dammit


No GRUB after installing Ubuntu beside windows 10

You have to disable fast startup in Windows:

Go to Control panel -> All control panel items -> Power options ->
Choose what the powers button do
Click on Change settings that are currently unavailable
Uncheck Turn on fast startup
Uncheck Hibernate
Restart entering Bios/UEFI
Move Ubuntu on top of Windows
Save and restart

Now everything should work!


Gnome Terminal hotkey change globally via cli

You can use gconftool-2 to set those options from command line.

Hit Ctrl+Alt+T to open terminal.

To disable run:

gconftool-2 -s /apps/gnome-terminal/global/use_menu_accelerators -t bool false
gconftool-2 -s /apps/gnome-terminal/global/use_mnemonics -t bool false

To enable run:

gconftool-2 -s /apps/gnome-terminal/global/use_menu_accelerators -t bool true
gconftool-2 -s /apps/gnome-terminal/global/use_mnemonics -t bool true


Firefox address bar not working after update to 50.0

I had the same problem with Firefox 50.1.0 on Ubuntu 14.04.

Fix: Disable InstantFox add-on.

I tried repairing and rebuilding the places.sqlite database in various ways as described here on mozillazine to no avail - I also had the same problem a couple of years ago on a different computer, and then rebuilding places.sqlite helped, but not this time.

Then I solved it by disabling the InstantFox add-on. I picked this because I knew it is designed to manipulate text in the address bar. When the add-on is disabled, the address bar works normally. When InstantFox is enabled, the problem returns.

I have sent an e-mail to InstantFox with this information.

If you don't have InstantFox, try disabling other add-ons one by one and re-check. Pick the ones that have something to do with the address bar first.

I don't know if the root cause is in Firefox itself, Ubuntu, or the add-on.


JRE and JavaFX is not included in JDK 11.
See the Important Changes and Information in Release note


How do I enable vlans in busybox when installing ubuntu server?

Okay, d-i does something a bit weird here.
If you turn off network configuration using
d-i netcfg/enable boolean false
most of the network stuff doesn't work, as network modules are not loaded.

What I did just to get vlans and bodning to work:

udpkg -i /cdrom/pool/main/l/linux/vlan*

insmod lib/modules/*/kernel/net/llc/llc.ko
insmod lib/modules/*/kernel/net/802/stp.ko
insmod lib/modules/*/kernel/net/802/garp.ko
insmod lib/modules/*/kernel/net/802/mrp.ko
insmod lib/modules/*/kernel/net/8021q/8021q.ko

modprobe bonding

for some reason modprobe bonding worked fine, but modprobe 8021q didn't work, even after udpkg.


I found this on the Arch Distro BBS maybe it can help:
Intel HD Graphics 4600 driver works as Intel Xeon E3-1200

You might try installing the Intel-microcode package as well.  You are most likely utilizing the Intel Processor's GPU, without knowing what model Mother Board you have.


Space needed for a little more than basic Ubuntu installation

30 GB is quite resonable it takes 4gb to install ubuntu and 4gb as swap area and rest are all your space you can install anything in it


"This computer currently has no detected operating systems."- Ubuntu 14.04 install Windows 8.1

Below is a link to a resource that walks you through the dual-boot install process for Ubuntu and Windows 8.1. It outlines the steps of the installation as follows:

Back up Windows
Create a bootable Ubuntu USB disk
Shrink the established Windows partition
Turn off(disable) fast boot
Turn off(disable) secure boot
Install Ubuntu from boot-disk
Boot repair
Fix the bootloader
Reboot into Ubuntu
Reboot into Windows

The steps I have listed are a concise version of the posted link. There are detailed instructions between listed steps, be careful to read and follow each; failure to do so could result in data loss, corruption, or system failure.
http://www.everydaylinuxuser.com/2014/05/install-ubuntu-1404-alongside-windows.html


Where to find the package versions for the next Ubuntu release

Debian and Ubuntu Developers Decide:

Most Ubuntu packages are imported from Debian sources. The process in Ubuntu is called "Debian Import" and occurs during the first four months of a release cycle.

Debian Import ends (with a few exceptions) at Debian Import Freeze, typically two months before release.

Whatever version is in Debian sid gets imported to Ubuntu.

Discussion happens in several places: IRC, mailing lists, and discourse.ubuntu.com.

Talking to developers about upgrading a package is generally a waste of time. They already know. Instead, the best way to get newer packages into Ubuntu is by participation: Help developers test and debug the newer packages in both Debian Experimental and later in Ubuntu pre-release.

For the example you gave of OpenCV, three different versions (3.3, 3.4, and 4.0) are all in Debian Experimental. The highest version that stops crashing and migrates to Debian Sid before Ubuntu's Debian Import Freeze (22 Aug, 2019) is likely to be in Ubuntu 19.10. More help testing and debugging makes it more likely a higher version will make it into Ubuntu 19.10.


What's the difference between the various printer connections?

http://www.cups.org/articles.php?L193+TFAQ+Q

Both the LPD and JetDirect/AppSocket protocols can be used over the Internet today, however neither of these protocols provides authentication services, access control, and all of the document management and formatting (including printer-specific commands) must be handled by the machine sending the document. If you don't know what kind of printer is on the receiving end you may not be able to successfully print your document!

This was back in 2005 so things might have changed


Increasing /boot partition by shrinking ubuntu-vg logical volume

My recommendation is to NOT try moving the PV. Instead, try this:

Shrink the PV by the amount you want your /boot partition to be in total. That is, if you want a 1GB /boot partition, reduce your PV by 1GB.
Create a new 1GB /boot partition in the freed space and create whatever filesystem you want to use on it.
Copy your current /boot partition's files to the new partition
Adjust your boot loader configuration for the new partition (this may entail re-installing your boot loader or just adjusting configuration files).
Test it all, being sure everything works with the new /boot partition. This will leave you with some wasted space where your old /boot partition is; but that's easily corrected....
Mark the former /boot partition as a new PV (that is, change its partition type code).
Run pvcreate on the new PV/former /boot partition.
Run vgextend to extend the VG to include the new PV/former /boot partition.
If desired, expand one or more LVs to make use of the extra space.

This process will be far quicker and safer than trying to move your main PV to make room for an expanded /boot partition. The drawback, of course, is that the PV will be fragmented, which will slightly degrade performance for files that may be stored in the former /boot partition. That said, the amount of space is small, so the number of files that will be affected is likely to be tiny. If the disk is an SSD, this effect will be non-existent.

Note also that the small amount of space you'd recover argues in favor of simply stopping at step #5 in the above procedure, or perhaps instead wiping or deleting the former /boot partition. That will make it available for future use should that become desirable. For instance, if you want to install a second Linux distribution on the computer or test the next Ubuntu release before upgrading, you could use the old /boot partition as a /boot partition for the new installation, in parallel with the main one.


Emulator: statvfs('/home/zf/...snapshots/default_boot/ram.img') failed: No such file or directory

I fixed the error like

  (Emulator: statvfs('/home/zf/.android/avd/Pixel_3_API_22.avd/snapshots/default_boot/ram.img') failed:
  No such file or directory)

by changing the group owner of ram.img to libvirt:

sudo chgrp libvirt ram.img

And changing the permissions to allow both read and write:

chmod 766 ram.img


After upgrading my Ubuntu 13.10 to 14.04, I constantly face internet connection disconnection

I think it is most likely something to do with your office's wifi setup. There is probably a configuration set up in a router that is causing the new update to stutter on a certain setting. There probably isn't a way to fix this, but just make sure that:

Your drivers are all updated.
This could cause some issues. Simply update your drivers and this could solve the issue.
Search specific issues on your WiFi adapter describing the issue your having.
If all else fails, do a fresh install of Ubuntu


Pam: How do I restrict users from using old password using pam?

The simplest way would be to edit your /etc/pam.d/common-password File and append use_authtok to the password line that contains pam_unix.so:
password    [success=1 default=ignore]  pam_unix.so obscure sha512 use_authtok

Next, you’ll need to set the pam_pwhistory.so module and set the remember value to 5 (or however many your password policy demands):
password    required    pam_pwhistory.so  remember=5

Put this above the line you just edited.
Finally, it’s important that you confirm the existence of the /etc/security/opasswd file. This is where used passwords are stored. If the file does not exist, you can create it like this:
sudo touch /etc/security/opasswd

Make sure it is readable and writable only by root with:
sudo chmod 600 /etc/security/opasswd

These changes take effect immediately, as there is no pam daemon, so there’s nothing to restart or reload.
There’s a lot more that pam can do if you need more fine-grained control over the reuse, length, and complexity of passwords


I have a Lenovo Z500 CORE i7 running on Ubuntu 14.04 and had experienced overheating too. This is due to the dedicated graphics card, a nVidia GT 635m, running constantly, instead of using the integrated Intel 4000 HD graphics chip.

You should set up your Ubuntu to use the internal graphics to decrease heat and when wanting to use the dedicated graphics, the nVidia, use it with Bumblebee, e.g. $ primusrun [your-app]. Follow the online instructions either here:
Bumblebee Installation

sudo add-apt-repository ppa:bumblebee/stable
sudo apt-get update
sudo apt-get install bumblebee bumblebee-nvidia virtualgl linux-headers-generic
Reboot

or here:
How to install nVidia drivers with Bumblebee on Ubuntu

If you want to run Ubuntu 14.04 in parallel with Win 8.1 you need to install it on a separate partition to Windows 8.1, using one that's available or shrinking a used one with caution. Follow these guidelines: WindowsDualBoot


Where is the XServer log file located in 18.04 and later

This is perhaps not as intuitive as everyone might think.  For my ubuntu mate 18.04 system using lightdm for the display manager I have valid data in /var/log/lightdm/x-#.log.
The user xsession log sould be in $HOME.
This answer is definitely not comprehensive.


Convert ifupdown using VLAN and Bridge-Utils to Netplan

I believe this config matches the intent of the /etc/network/interfaces file. It does not match the names of the vlan interfaces as shown in the screenshot; it is unclear why your vlans are named 'vlan2' and 'vlan3' in the screenshot but 'vlan4' and 'vlan5' in the e/n/i.

network:
    version: 2
    renderer: networkd
    ethernets:
         eno1:
            dhcp4: no
    bridges:
        # standard network
        standard:
            interfaces: [eno1]
            addresses: [172.16.0.6/23]
            gateway4: 172.16.0.1
            nameservers:
                search: [example.com]
                addresses: [10.0.0.244]
        printers:
            interfaces: [vlan5]
        gaming:
            interfaces: [vlan4]
    vlans:
        vlan5:
            id: 5
            link: eno1
        vlan4:
            id: 4
            link: eno1

You should double-check what the vlan IDs are on your existing interfaces with ip -d link show vlan2 | grep 'vlan protocol' (and the same for vlan3) and adjust the id values above to match what is required for each interface.


My laptop's fan overrun. CPUs temperature is extremly high

I don't understand the screen info stuff but from a mechanical point of view, assuming that the fan and heat-sink are clean, and that the air vents are all clear, I'd try replacing the heat-sink paste. I use MX-4 myself, it made a big difference to an old laptop of mine.

Another tip: stick bigger feet on the bottom of your laptop to make sure there's plenty of air flow. Web browsing is very CPU intensive so if it's a small one it'll be maxed-out and running hot most of the time.


What are the partitions on dual-boot Windows/Ubuntu hard disk?

As always, if you have any data that needs to be saved, make a backup of the entire drive using a program such as clonezilla before re-partitioning.  The safest way to resize the windows partition is with Windows' Disk Management program.  However, Windows likes to spread out data and has "unmovable" files like the pagefile and system restore files which often limits the amount of space available to shrink the volume, even when there is a quite a bit more "free" space in that partition.   See this post which describes how to free up more space on the volume.  You will benefit from defragmenting the windows volume beforehand as well as turning off hibernation.
Windows is messy with partitions and loves to gobble the whole disk with partition, so your sda4 and sda6, as the flags suggest, are diagnostic and recovery tools for Windows.  Unfortunately, they've sandwiched your Linux partition, which is nearly full. If you shrink the Windows system partition, you will be adding unallocated space at the beginning of your Linux partition.  The key point is that the unallocated space is contiguous with your Linux partition, which it will be.
Once you've freed the unallocated space, you can reboot to your Unbuntu live USB and use GParted to expand the unallocated space into your Linux volume.  You can find some discussions on the considerations for adding to the volume here and here.  I hope this helps get you started.


No sound from HDMI audio output (NVIDIA)

I solved the issue with the same Lenovo ThinkCentre Q150 by switching to OpenELEC 7 Beta 3. link  This version has been stable with only minor audio glitches. If you're heart is set on Kodibuntu, you could pull kernel and driver configuration settings from OpenELEC via SSH.

There were other posts online I found which pointed to a kernel issue which caused HDMI, to stop working.  I tried the default version of KodiBuntu, which failed HDMI.  I then did an upgrade and HDMI still didn't work.    I then attempted to upgrade the KodiBuntu kernel to a known working stock ubuntu version, and ran into dependency issues.  USB stopped working and I was unable to proceed.  After wasting several hours, OpenELEC 7 Beta 3 solved the problem for me.


When the root partition fills up in Linux, it's hard to do anything.

Run sudo apt clean and sudo apt autoclean and sudo apt autoremove to give yourself enough room on the hard drive to function.

Then start removing/uninstalling whatever you don't need, or increase the size of your root partition.


How to use Bash Script to open URLs in a different profile with Firefox?

If you omit the profile, firefox will open the URL in one of your open Firefox programs. You have to explicitly mention it:

firefox -P 'Another Profile' http://example.com/

You can also open multiple URLs at once and combine it, removing the need for a sleep:

firefox -P 'Another Profile' http://example.com/ http://example.net/


How do I enable double-tap (right click) drag on touchpad?

You can tune this with the gnome tweak tool gnome-tweaks or with this simple gsettings command :

gsettings set org.gnome.desktop.peripherals.touchpad 'fingers'

You can also install the gnome-tweaks tool

sudo apt install gnome-tweaks


How do I change the login manager in Lubuntu

You can install it just by sudo apt-get install lightdm lightdm-greeter-example-gtk. In order to have a better view, have a look at this wiki.


end Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block (0,0)

Has a similar problem just now. Apparently your /boot partition is out of free space which causes this problem when updating to a new kernel. Select manually an older kernel in the grub menu so you can boot. Then to clean up /boot use sudo apt-get autoremove or delete old kernel files manually so you keep at least one working one. Then add the new kernel to grub:
update-initramfs -u -k version, where version is the new kernel version. Then run update-grub to update the grub file and it should boot again.


Without uninstalling anything, you can fix this by changing a line in the file
/usr/share/pyshared/papyon/service/description/AB/__init__.py.

Edit it as root by running:

sudo -H gedit /usr/share/pyshared/papyon/service/description/AB/__init__.py

Change line 23 from this:

url = "http://contacts.msn.com/abservice/abservice.asmx"

To this:

url = "https://local-bay.contacts.msn.com/abservice/abservice.asmx"

Or to this:

url = "https://local-sn.contacts.msn.com/abservice/abservice.asmx"

Reboot and test it, it's working for me!


Unable To Install Rainlendar2 For Ubuntu 16.04 LTS (32 & 64 Bit)

The correct way to install RainLender in Ubuntu 16.04 is as follows

Download the .deb file from their download site labeled with (Debian/Ubuntu). I am here demonstrating from terminal for 64-bit architecture.

wget -c http://www.rainlendar.net/download/rainlendar2-pro_2.13.1.b147-1_amd64.deb

Change the link to pro or lite depending on your need in the command.
Once the download is complete, install it with dpkg

sudo dpkg -i rainlendar2-pro_2.13.1.b147-1_amd64.deb

Again change the filename accordingly. The terminal can autocomplete the filename for your if you press Tab key twice quickly.

Though this will install rainlender, but the software would stay in unconfigured, because some of it's dependency will not be satisfied. You may see the output like this after

Selecting previously unselected package rainlendar2-pro.
(Reading database ... 651477 files and directories currently installed.)
Preparing to unpack .../rainlendar2-pro_2.13.1.b147-1_amd64.deb ...
Unpacking rainlendar2-pro (2.13.1.b147-1) ...
dpkg: dependency problems prevent configuration of rainlendar2-pro:
 rainlendar2-pro depends on libwebkitgtk-1.0-0; however:
  Package libwebkitgtk-1.0-0 is not installed.

dpkg: error processing package rainlendar2-pro (--install):
 dependency problems - leaving unconfigured
Processing triggers for bamfdaemon (0.5.3~bzr0+16.04.20160523-0ubuntu1) ...
Rebuilding /usr/share/applications/bamf-2.index...
Processing triggers for gnome-menus (3.13.3-6ubuntu3) ...
Processing triggers for desktop-file-utils (0.22-1ubuntu5) ...
Processing triggers for mime-support (3.59ubuntu1) ...
Errors were encountered while processing:
 rainlendar2-pro

To fix this dependency problem, again type in terminal

sudo apt-get -f install

It will then download and install other packages to fullfill dependencies and you can then run it.

Here is the screenshot running RainLender in my Ubuntu (with KDE5)


How can I trace a crash in a program that crashes X?

The relevant component you need to trace is X, not the application causing the crash.

There is some detailed information at the Ubuntu wiki:
https://wiki.ubuntu.com/X/Backtracing


You can use SSH_ASKPASS to tell ssh what method to use to provide the answer. For example i use keychain for my keys management so I have a script here:

~/.config/autostart-scripts/ssh-add.sh

With:

/usr/bin/keychain --eval --agents ssh --inherit any mykey

Here mykey is the public key. In my case, I find useful to name them.

At next log in, you will have KDE to ask you to unlock the key, and it will be valid for the rest of the session.


Xubuntu, combinations Ctrl+key don't work when I use Ctrl as hotkey for switching keyboard layout

As a solution I installed xcape - https://github.com/alols/xcape

Follow instruction from README.md how to install it on your system.

Then run

xcape -e 'Control_R=Alt_L|Shift_L'

and add the command to the autorun.

Pay attention that your command may be different if you don't use Alt+Shift as default shortcut for switching keyboard layout.


How to install 11.04 on a different partition?

When you boot to the graphical installer (not the installer in Windows) then you'll be able to choose which harddisk to install it on. If you already have Windows installed there, then you can choose how much disk space each operating system shall have. It's just a slider from 0% to 100%, although those extremes won't be valid if you want to have both. :)

The installer will add entries to your boot menu automatically so that you can choose between Windows and Ubuntu when you start the computer.


You've two ways to change the password.

Using GUI - Go to System -> Preferences -> About Me, which will display the following window. Click on Change Password button.
Command - Open up a terminal (you can do that by holding CTRL+ALT+T) & type as below;

  passwd username

This will prompt you to type your new UNIX password by confirming once.

Hope it helps!


Updated ubuntu 18.04 now get stuck in 5 dot screen after grub

I have the same issue. Ubuntu 18.04.2 LTS was working fine, until I updated and rebooted and now I can't get beyond the 5 dot screen. Sometimes the screen goes to black, sometimes there's no more video signal.

I updated BIOS (Asus A320M-K), put memory speed back to default, removed SATA disks, no effect. I can get into recovery mode, I ran dpkg to repair broken packages but this didn't fix the issue either.

I also have an AMD Ryzen APU (2200G) and I'm using the AMDGPU or AMDGPU-PRO driver (I forget which).

EDIT: I fixed the issue by going into recovery mode, installing Mesa from the Padoka PPA and removing the AMDGPU driver. This might work for you if you also have the AMDGPU driver.

sudo add-apt-repository ppa:paulo-miguel-dias/pkppa
sudo apt-get update && sudo apt-get dist-upgrade
sudo amdgpu-pro-uninstall


error in displaying local wordpress website

Look at assets urls:

In Chrome, press F12 (Developer Tools), open tab - Network and look for missing files, they are red (if not shown, refresh page with dev tools opened).

I think you have wrong site name or site url in your wordpress configuration, and your instalation is looking for files from http://localhost/wp-content


Horizontal lines in video playback (all players)

You might experience a bug related to v-syncing. If you are using unity, try installing ccsm and play around with the v-sync option under opengl settings.


Follow these steps :

cd Desktop
mkdir working-dir
cd working-dir
cp ~/Downloads/PacketTracer_730_amd64.deb .
ls
wget http://ftp.br.debian.org/debian/pool/main/d/double-conversion/libdouble-conversion1_3.1.0-3_amd64.deb http://archive.ubuntu.com/ubuntu/pool/main/libj/libjpeg-turbo/libjpeg-turbo8_2.0.3-0ubuntu1_amd64.deb http://archive.ubuntu.com/ubuntu/pool/main/libj/libjpeg8-empty/libjpeg8_8c-2ubuntu8_amd64.deb
ls -l
chmod +x *
ls -l
sudo dpkg -i *
sudo featherpad /var/lib/dpkg/status #featherpad here, is my text editor
    #ctrl+f (search) > Depends: libdouble-conversion1, qt-at-spi > (delete-this-line) > save & close
sudo apt --fix-broken install
packettracer

I also put a video on YouTube https://www.youtube.com/watch?v=5FuBKG49bIY it shows the same process but could be more helpful.


How to find the other system without knowing name or IP of the other system in LAN?
You can use nmap in the terminal, for example:

nmap 192.168.0.*

if 192.168.0.0 is your LAN. This will print you all network clients in your LAN (which can be discovered). Sometimes this might help, if other machines don't show up under Network.

Reference:
https://askubuntu.com/a/98694/56338


Accidentally removed every package containing text "win"

You may want to to do a backup followed by a complete reinstall.

I have just tried this on a Virtual machine to see the effects.

sudo apt-get remove wine\*

This warned me that I was about to remove 120 packages including

Removing account-plugin-windows-live ...
Removing aisleriot ...
Removing apt-transport-https ...
Removing nautilus-share ...
Removing apturl ...

amongst others

I would have stopped there on a real system as that should be enough to tell you you are doing something wrong.  But as this is only a test system I pushed on.

My complete list is here : Ubuntu Pastebin

You can find a list  on your system at /var/log/apt/term.log  I copied this to an external drive and printed it out.

When  I rebooted Unity had gone so I had to use Ctrl+Alt+F6 to get to a text console.

You may be able to restore each of these with

sudo apt-get install package

replacing package with each of the package names.  I've tried a few and it looks like its working though you will get some "this package is already installed" errors as installing one package may pull others in as dependencies so its already installed by the time you ask to install it.

It will probably be easier to boot with a live DVD or USB stick copy your personal files then reinstall than to manually put all the packages back.  That's what I would be doing if it had happened to me.


How do I demand a password on single user mode?

If you set a password for the root user, that password will be required also to login in single-user-mode.


EDIT

I found out that a pin-priority of 1001 will allow downgrades of this priority set so you can downgrade all existing Ubuntu packages that were mistakenly installed because of the Kali Repo. This should really help to fix things and should also prevent dependency issues in the future.

First, edit your /etc/apt/preferences file before you do anything else.

Run the following commands:

sudo nano /etc/apt/preferences

Now, copy and paste the following into the file:

Package: *
Pin: origin ppa.launchpad.net
Pin-Priority: 1001

Package: *
Pin: origin ph.archive.ubuntu.com
Pin-Priority: 1001

Package: *
Pin: origin security.ubuntu.com
Pin-Priority: 1001

Package: *
Pin: origin extras.ubuntu.com
Pin-Priority: 1001

Package: *
Pin: origin repo.kali.org
Pin-Priority: 600

Package: *
Pin: origin extras.ubuntu.com
Pin-Priority: 1001

Package: *
Pin: origin security.kali.org
Pin-Priority: 600

Package: *
Pin: origin http.kali.org
Pin-Priority: 600

Press CTRL + o and then press ENTER to save the file. Press CTRL + x to exit nano.

Next, run:

sudo apt-get clean
sudo apt-get update

Then, purge libc6-dbg and downgrade libc6:i386, libc6-dev, and libc6:

sudo dpkg -P libc6-dbg
apt-get download libc6-udeb=2.19-0ubuntu6 libc6-dev=2.19-0ubuntu6.6 libc6=2.19-0ubuntu6.6:i386
sudo dpkg -i libc6_2.19-0ubuntu6.6_amd64.deb
sudo dpkg -i libc6-dev_2.19-0ubuntu6.6_amd64.deb
sudo dpkg -i libc6_2.19-0ubuntu6.6_i386.deb

Also, downgrade gdebi:

sudo apt-get install gdebi=0.9.5.3ubuntu2

If all goes well, run the following commands. If not, please post your errors.

To install google-chrome-stable:

sudo apt-get clean
sudo dpkg -P google-chrome-stable
sudo apt-get update
sudo apt-get upgrade

Please post any errors. If there are no errors, continue:

wget https://dl.google.com/linux/direct/google-chrome-stable_current_amd64.deb
sudo gdebi google-chrome-stable_current_amd64.deb

gdebi will handle all the dependencies for you.


It looks like between 18.04 and 19.04 the ar command lost some supported targets.

18.04:

ar: supported targets: elf64-x86-64 elf32-i386 elf32-iamcu elf32-x86-64 a.out-i386-linux pei-i386 pei-x86-64 elf64-l1om elf64-k1om elf64-little elf64-big elf32-little elf32-big pe-x86-64 pe-bigobj-x86-64 pe-i386 plugin srec symbolsrec verilog tekhex binary ihex

19.04

ar: supported targets: elf64-x86-64 elf32-i386 elf32-iamcu elf32-x86-64 pei-i386 pei-x86-64 elf64-l1om elf64-k1om elf64-little elf64-big elf32-little elf32-big pe-x86-64 pe-bigobj-x86-64 pe-i386 plugin srec symbolsrec verilog tekhex binary ihex

It's possible the archive you originally created is in one of those no-longer supported formats. So appending to it won't work. You may have to re-create the archive by unpacking and re-packing it in a supported target format.


How to compile c++ to Dll file in Ubuntu

From your comment I assume you are asking about

Cross-Compilation for Windows

This is an entirely different subject. It requires more than just changing your makefile. However, this question has been asked before:

How to program for Windows in Ubuntu?
Is it possible to write programs for other OSs in Ubuntu?
cross-compiling with clang using mingw (no answers yet)
What is the /opt/mingw64 /opt/mingw32 equivalent for Ubuntu

If your project is in C or C++ you can use MinGW tools and the same sort of linux based compile tools that use gcc/g++. You can install MinGW like this:

sudo apt-get install gcc-mingw32

I suggest that you study this guide for qt/win32 cross compiling using MinGW tools.

If your project is mainly for C#, you might be better off with MonoDevelop. From their website:

  MonoDevelop enables developers to quickly write desktop and web applications on Linux, Windows and Mac OS X. It also makes it easy for developers to port .NET applications created with Visual Studio to Linux and Mac OS X maintaining a single code base for all platforms.


Update Ubuntu 14.04 to 15.10 - black screen

That sounds familiar to me.

This usually happen if the graphics driver is partially compatible,
incorrectly installed packages, or just a bad computer configuration.

I would wait for a few hours (if you have a good internet conection like 20 MB/s or better). Maybe in 2 hours it could react to your mouse/keyboard.

If that doesn't work, as @Pilot6 said, you can do a totally fresh installation to Ubuntu 16.04. (This could be the best solution.)


/media/LACIE sounds like you're handling a pre-formatted drive, most likely with the FAT32 filesystem. According to Wikipedia, the maximum file size for FAT32 is about 4GB.

I suggest to reformat the drive to either ext4 (for supporting Linux file permissions) or NTFS (if you need to share the drive with windows users).

How funny, but you've now to backup your backup first before reformatting ;)


In basic usage it is used for 'search and replace' with strings.

echo "The quick brown fox jumps over the lazy dog" | sed 's/dog/cat/'

returns

"The quick brown fox jumps over the lazy cat"

Sed really shines when regular expressions are used with it.

You might like to take a look at this article about sed, its quite comprehensive.


pluma editor open document on a new instance

Edit /usr/share/applications/pluma.desktop and change Exec=pluma %U to Exec=pluma %U --new-window

the solution was provided by this forum.


How can the toolbar show only the windows active on my current virtual desktop?

Refer https://manual.lubuntu.me/stable/5/5.1/lxqt-panel.html for details on using the panel.

From the Configure Panel option (prior link) you can select the Task Manager and then Settings.

The first option is to "Show only windows from desktop" - Make that say Current to see only windows for your current desktop in the Task Manager on the Panel.


Add your user to the vboxsf group:

sudo usermod -aG vboxsf $(whoami)
sudo reboot


Install program from source to chroot env

If you're not short of a bit of space, you could use debootstrap to install a minimal complete OS in your chroot. This then makes apt available in your chroot.

To start with:

sudo apt-get install debootstrap

To setup a new chroot:

sudo debootstrap oneiric /path/to/chroot
sudo chroot /path/to/chroot /bin/bash

Voila, you're in a new minimal Ubuntu installation. apt-get will work from here. So now you could even install gcc/make et al, and do your entire make install in the chroot, which should pretty much guarantee the end result will work properly (all the libs will be present and so forth).

There's a few other steps you should do like setting up /proc in the fstab in the chroot, see the debootstrap manpage (under EXAMPLES).


Hide notification bar on Ubuntu phone (QML)

You can do this by putting your MainView in a QtQuick Window and setting visibility: Window.Fullscreen on that.  I'm not sure that this is the recommended solution, but it does seem to work.

import QtQuick 2.0
import QtQuick.Window 2.2
import Ubuntu.Components 1.1

Window {
    visibility: Window.FullScreen

    MainView {
        useDeprecatedToolbar: false
        anchors.fill: parent

        Page {
            title: "Fullscreen"
        }
    }
}


Can’t enable 4k resolution on external display

Thanks to awesome people at Nvidia forums:
https://forums.developer.nvidia.com/t/cant-enable-4k-resolution-on-external-display/165719
I got the correct modeline:
xrandr --newmode "3840x2160_30.00" 297.0 3840 4016 4104 4400 2160 2168 2178 2250 +hsync -vsync
xrandr --addmode HDMI-2 "3840x2160_30.00"
xrandr --output HDMI-2 --mode "3840x2160_30.00"


How do I fix an 'unknown key' issue so the key works as expected?

Install KeyTouch. If your keyboard is not supported out of the box, you need both the keytouch and keytouch-editor packages. Run the keytouch editor, and configure your keyboard (it's probably not exactly a 9205, possibly completely different, given that the 9205 is not a laptop keyboard).

The reason xev doesn't see the multimedia keys is that the kernel doesn't transmit them if they haven't been properly introduced (that's what the “unknown key released, use setkeycodes” messages mean). KeyTouch will do it (in a more user-friendly way than setkeycodes), and will also handle the higher-level aspects such as configuring the eject key to eject the CD.

The Right key not working is a bit worrying however. Does it trigger kernel messages? It should have worked out of the box, since it's a standard key.

Other relevant Ubuntu wiki pages are Hotkeys/Troubleshooting (but try KeyTouch first) and Hotkeys/Architecture (explaining this is not as simple a it should be under the hood).


Create bash script that allows you to choose multiple options instead of just one?

From the discussion in the comments it is apparent that your main concern is to create as script with multiple selections, rather than focus on copying/moving files themselves, and the file operations are just an example. This functionality can be achieved via dialog command, which allows creating text user interfaces, with --checklist flag specifically; however there's nothing in the standard shell-only toolbox to achieve what you want. Hence, dialog is an appropriate tool for this job.

Below you will find an example script. While the script implements only 3
options that were discussed, it provides a decent starting point which users can extent further, and also addresses mutually exclusive options as mentioned in the comments. Particularly, the multiple selection is addressed in menu() function, which serves as a wrapper for dialog with --checklist option

To keep things simple, all you really need is this:

output=$(dialog --clear --backtitle "Backtitle. Use <SPACE> to select." --title "My Dialog" \
       --checklist "Select all that apply"  50 50 100 \
       checksum "SHA-256" off \
       copy "Copy only (exclusive with move)" off \
       move "Move only (exclusive with copy)" off 2>&1 > /dev/tty)

This saves the selection of multiple items to variable $output. Note that `2>&1 > /dev/tty) at the end are crucial to saving the return value into variable.  But see the script below for more practical example:

#!/bin/bash

puke(){
    # function to exit with specific error message
    # analogous to 'die' in Perl
    printf ">>> Errors were encountered: %s\n" "$1" && exit
} > /dev/stderr

menu(){
    # dialog --help documents the option as follows:
    # --checklist    <text> <height> <width> <list height> <tag1> <item1> <status1>...
    # tags are what the output returns.
    # We can use word-splitting
    # and iterate over output of this function in order. Of course first option
    # being checksum will always work and is not mutually exclusive with anything else
    dialog --clear --backtitle "Backtitle. Use <SPACE> to select." --title "My Dialog" \
           --checklist "Select all that apply"  50 50 100 \
           checksum "SHA-256" off \
           copy "Copy only (exclusive with move)" off \
           move "Move only (exclusive with copy)" off || puke

} 2>&1 1>/dev/tty

select_file(){
    dialog --backtitle "Choose file by typing or navigating and selecting with <SPACE>" --fselect "/etc/" \
           20 50  || puke
} 2>&1 1>/dev/tty

iter_actions(){
    # variables are available to child functions
    # Since we call iter_actions in main(), this
    # function also knows about main's variable $fselect

    for i ; do
       case "$i" in
           checksum) sha256sum "$fselect" ;;
           copy) cp "$fselect" /tmp ;;
           move) mv "$fselect" /tmp ;;
       esac
    done
}

main(){
    # here I'm using /etc but you can use $PWD to default to user's
    # current working directory, or accept positional parameters from command-line
    # as in $1, $2 and so forth
    fselect=$( select_file "/etc" )
    actions=$(menu)
    printf "\r%b" "\033c" # this clear the screen

    case "$actions" in
       *copy*move|*move*copy) puke "Mutually exclusive options selected" ;;
        *) iter_actions $actions ;; # note here variable is unquoted on purpose
    esac
}

# script entry point
main "$@"

For further research:

How can I create a select menu in a shell script?
How to get dialog box input directed to a variable?

Why write an entire bash script in functions?


"Authentication Required" wifi password request loop on Ubuntu 20.04

I figured out what the problem was!
I had updated my linux kernel on Saturday, and that had overwritten my (fairly ancient) special surface-book linux kernel that I got from Jakeday's git repository. To fix the problem, I got the newest, top-of-the-line kernel from here:
https://github.com/linux-surface/linux-surface
I had to make sure to follow both its installation instructions (https://github.com/linux-surface/linux-surface/wiki/Installation-and-Setup) and sign the kernel using their premade public key & associated instructions (https://github.com/linux-surface/linux-surface/wiki/Secure-Boot).
It's so nice to be done with this!


Netplan bond/bridge MTU setting not being honored on Bionic system

I resolved this by adding the MTU settings to both the "bonds:" and "bridges:" sections (removed from the "ethernets:" section).  Here is the working config:

# Ceph network configuration
network:
  version: 2
  renderer: networkd
  ethernets:
    eth2:
      dhcp4: no
      optional: true
    eth3:
      dhcp4: no
      optional: true
  bonds:
    bond1:
      interfaces: [ eth2, eth3 ]
      mtu: 9000
      parameters:
        mode: 802.3ad
        mii-monitor-interval: 100
        lacp-rate: fast
  vlans:
    bond1.220:
      id: 220
      link: bond1
      optional: true
  bridges:
    br-ceph-access:
      optional: true
      addresses: [ 172.16.238.133/24 ]
      interfaces: [ bond1.220 ]
      mtu: 9000
      parameters:
        forward-delay: 9
        hello-time: 2
        max-age: 12
        stp: false


Did you check if the IP for the server is Class C (Local Network) or has an Internet IP. If it is local you will not be able to connect to it except rerouting from the Internet IP assign to that network.

Class C IP are for example: 192.168.0.1 (Common one used in cafes) 192.168.1.10 and tipically any 192.168.X.X

In your question the ip 192.168.1.46 is Class C which is not accessible by normal means except rerouting connections.

The other ip 122.XXX.XXX.XXX is an Internet IP which will work

What i recommend is telling the router that connects to the Internet (The one that has the 122.XXX.XXX.XXX) to redirect all connections to that port to the 192.168.1.46 IP in the network.


Adding the following entries to /lib/udev/rules.d/69-libmtp.rules did the trick

ATTR{idVendor}=="05c6", ATTR{idProduct}=="6764", SYMLINK+="libmtp-%k", MODE="660", GROUP="audio", ENV{ID_MTP_DEVICE}="1", ENV{ID_MEDIA_PLAYER}="1", TAG+="uaccess"
ATTR{idVendor}=="05c6", ATTR{idProduct}=="6765", SYMLINK+="libmtp-%k", MODE="660", GROUP="audio", ENV{ID_MTP_DEVICE}="1", ENV{ID_MEDIA_PLAYER}="1", TAG+="uaccess"

I got this solution when I asked the same question in OnePlus forum


You need to install full feature drivers and the printer utility.

Go to Epson drivers site

Search for you printer and download Printer driver 1.0.0 and Printer utility: epson-inkjet-printer-201305w_1.0.0-1lsb3.2_amd64.deb, epson-printer-utility_1.0.0-1lsb3.2_amd64.deb.

Copy these files to your home folder and run in terminal

sudo dpkg -i epson*.deb
sudo apt-get install -f

The setting is here


Did you try the official Virtualbox ppa? If not I suggest purging and trying that.


Got it to work.   The trick is similar to #3, but use a shell script in a file rather than inline in the upstart.conf.  That way you can skip the -e and you can use bash rather than dash.

If you really want to avoid a separate script, you can bypass the -e behaviour by using ||:

script
  cmd &
  PID=$!
  wait $PID || export EXIT_CODE=$?
  if [ $EXIT_CODE -eq 139 ] ; then cleanup ; fi
end script


I don't see the Unity section in Firefox preferences

The desktop integration options are now located in the "General" section of the preference pane in Firefox, at the bottom "Desktop Integration".


It depends on your set-up. They are stored in several locations. The best way for you to find them is to open your Terminal Ctrl-Alt-T, then type sudo locate compiz and press Enter. It will return several results, but you can tell by the names which will contain your settings.


How to prevent Ubuntu One for Windows from automatically signing on to my account?

There is currently no easy way of doing what you want to do. Also, I need to point out that even when the Ubuntu One syncdaemon is not running, the files of the folders you've selected will still be present and anybody with access to the machine will be able to inspect them, and any changes made to the files while syncdaemon is not running will be synchronized up the server as soon as it starts.

Anyhow. You want to do two things: prevent Ubuntu One (both the syncdaemon and the control panel icon) from running automatically, and, remove the credentials so the login isn't automatic when it is run.

The first is a little bit fiddly, but you only need to do it once: run regedit, and under HKEY_CURRENT_USER look for Software\Microsoft\Windows\CurrentVersion\Run. Remove both Ubuntu One and Ubuntu One Icon:

Then, every time you log want to log out (and that's inconvenient, I know), you stop Ubuntu One, go to Control Panel/Credentials, expand the Ubuntu One entry, and remove it from the vault:

HTH,


Ubuntu 13.04 won't boot past splash screen after installing graphics driver

The problem was with the graphics drivers I downloaded. I went into the recovery console and removed them through the terminal. I needed to use bumblebee to get my graphics card up and running.


Which version of Hadoop is compatible with Ubuntu 17.10?

The only requirement for Apache Hadoop is to have installed JDK. Hadoop 2.6 and earlier supports Java 6, 2.7-2.9 supports Java 7, 3.0.0 and newer supports Java 8. So, if you have Java 8 in your Ubuntu, you can use any version of Hadoop. But it's recommended to use new releases from here: http://hadoop.apache.org/releases.html (2.7.5 or newer). It can depend on what software you want to use with your Hadoop cluster.


There may be folders on your external hard drive that are encrypted. If you attach your external hard drive to a computer that is running Windows and unencrypt the encrypted folders, then the contents of these folders will be readable from Ubuntu.


My Vaio VPCSA had a similar problem.

I replaced a line in /etc/defalut/grub (1):

GRUB_CMDLINE_LINUX="video.allow_duplicates=1 radeon.modeset=1"

It fixed the problem for Ubuntu 12.10. However, that's not enough for Debian/unstable.
In addition, I had to add a line to /etc/modprobe.d/blacklist.conf (2):

blacklist radeon

And to /etc/rc.local BEFORE exit 0; (3):

modprobe radeon modeset=1
mount -t debugfs none /sys/kernel/debug/
echo OFF > /sys/kernel/debug/vgaswitcheroo/switch

If you have issues, start with (2). It has reliably resulted in a bootable system, than proceed with (3).


startup/shutting down screen showing Xubuntu's bootsplash and not Ubuntu's

Run the following commands

# Select your desired plymouth theme
sudo update-alternatives --config default.plymouth

# Rebuild / update your initramfs with the new theme
sudo update-initramfs -u

If you prefer a graphical tool you can try plymouth manager, it is available via a ppa

sudo apt-add-repository ppa:mefrio-g/plymouthmanager
sudo apt-get update
sudo apt-get install plymouth-manager

There are several themes available in the same ppa

https://launchpad.net/~mefrio-g/+archive/plymouthmanager


How to uninstall the snap version of digiKam?

As @Jos already stated in a comment, the right command to remove the snap package is snap, not apt :
sudo snap remove digikam

Then you can install the stable version from the digiKam page :
https://www.digikam.org/download/
It's an AppImage so you have not to struggle with snap.
I was a little bit reluctant at first, but nobody maintain a ppa repository with up to date version of digiKam and it's not often updated so downloading an AppImage is fine.


How can I stop the Unity bar from causing cursor delay between two monitors?

You must have sticky borders enabled. Remove the option sticky borders.

A similar problem has been answered here: How do I disable mouse magnet on middle edge with multi monitors?


I have wished for a "complete list".  I used to have a filter program compiled that would escape every "special character" that I could think of.

A good start: ! ? $ % $ # & * ( ) blank tab | ' ; " < > \ ~ ` [ ] { }

I'm sure there are others that I have missed.


Does anyone know of a program like Elastics for Linux?

https://github.com/coteyr/unity-ec2-lense

I created a simple unity lens (using singlet) to do what I need. It's working, with more testing and some clean up, it can serve as an example to others.

I will leave the question open a while longer to see if there are any other answers.


Symbolic links on file system directories between different drives?

Short answer: Either one should work fine for that.

Longer answer:
As long as everything works, they should function almost identically. The only difference would be in what happens if for some reason they don't work.

Think of a symbolic link like a "Shortcut" file. It's basically just a small file that tells you where to go next, and the OS (usually) handles that redirection for you automatically.

A mount, on the other hand, directly alters your view of the filesystem - whenever you request a file from a mounted directory, the kernel just silently hands you the actual file instead.

In the event that the target filesystem is ever unavailable, symlinks and mounts will behave differently. A symbolic link will point to a location that doesn't exist - and things will probably just start to throw errors. A mount, however, will immediately fail since there's no filesystem to mount. Then any attempts to read from or write to it will pass straight through to the (probably empty) directory that was supposed to be covered up by the mount.

Man pages: ln(1), mount(8)

All that being said, I would personally advise against moving any system-critical files (like /sbin) off the main drive. Moving /home (or some of its subdirectories) to a second drive, however, is a very common and accepted practice.


tab-completion only works for table names (mysql 5.5 on ubuntu 14.04)

Resolved: I wasn't specifying a database name when invoking the mysql command line interface!

Auto-completion works as expected if I go in as:

  mysql -u root -p mysql # or
  mysql -u root -p mydatabase

as opposed to:

  mysql -u root -p

(and --auto-rehash clearly is on by default as per the docs)


when saving (you did edit it with root privileges I assume)  and leaving /etc/default/grub do the following command:
sudo update-grub
EDID is the information your monitor sends to your videocard. It consists of mainly maximum resolution and refreshrate. Not all monitors send this info, especially old ones. So if the absence of EDID left you stuck in a much lower resolution than your monitor is capable of, then it is time to reach for the manual override :-)
Yes, Ctrl-Alt-F1 is a virtual termina a.k.a console. It runs on the bare OS even before the X-window system starts. Ctrl-Alt-T is a program running on the X-window system and is called a terminal emulator. The most important difference is that the virtual terminals will still be there if the Xwindow system kicks the bucket or is screwed up beyond working state :-)


Lightdm low-graphics mode options not selectable

Try boot at recovery mode, low graphics, and choose"resume" option, after login, go-to settings/display and turn off every monitor not in use...


how to find the Apache OpenOffice installation directory DEBS folder

You probably missed an instruction in step 2: "after extracting..."
You will find the downloaded file Apache_OpenOffice_4.1.6_Linux_x86_install-deb_en-US.tar.gz in the directory where you issued the wget command.


avoiding grub probleme when reinstalling a new version of ubuntu

When you install Ubuntu, and if you chose "Something Else" picked manual partitioning, you'll get an option to select the device for GRUB (bootloader) installation (there are pics in this answer). If you didn't modify it (or used one of the other options instead of manual partitioning), you will likely have GRUB installed in /dev/sda, and if you choose to use it for GRUB the next time when you install Ubuntu, the olde GRUB will be overwritten. So you should be safe.


Help with BIOS/UEFI settings on Thinkpad T495

You may check the following to ensure to be able to boot with your computer.

Check into your BIOS

From Startup tab > Boot, ensure you have HDD0 enabled on order 1.
From Security tab > Secure Boot, check Secure Boot is Disabled.

Check into your hard drive

If you are still unable to boot up, start from an Ubuntu USB boot disk, and from command prompt, run the following commands.

sudo fdisk -l

Now from your /dev/sdxx list, you should have one EFI system partition.

Mount this partition into a temporary folder

sudo mount /dev/sdxx /mnt

Now check the content, the minimum is having

./EFI/BOOT/grubx64.efi : this is grub efi boot file
./EFI/BOOT/BOOTX64.EFI : this is the windows boot file, but also the failsafe.

If those file are missing, you might be unable to boot your computer. You may reinstall it with.

grub-install /dev/sda

You can also read this complete guide to debug where your issue is.

  https://wiki.debian.org/GrubEFIReinstall


Use command with users option

sudo mount -o users /dev/sdXY /mountpoint

The users option gives rights to (un)mount for everybody.

The device node is a special device pseudo-file inside /dev directory. You can find information about your Storage's device node in Disks utility. X and Y are drive letter and partition number respectively.

You should modify your /etc/fstab file to make the changes permanent. Use sudo gedit /etc/fstab, find the line with /media/Storage and add users option to the 4th column:

# /etc/fstab: static file system information.
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>

proc    /proc   proc    nodev,noexec,nosuid     0       0
#Entry for /dev/sda8 :
UUID=f406231f-88c0-4bcc-8f71-84f962ed0306       /       ext4    errors=remount-ro       0       1
#Entry for /dev/sda6 :
UUID=5CFA3E3AFA3E112E   /media/Games    ntfs-3g defaults,locale=en_US.UTF-8     0       0
#Entry for /dev/sda3 :
UUID=AC7C4EC27C4E86D4   /media/OS       ntfs-3g defaults,locale=en_US.UTF-8     0       0
#Entry for /dev/sda2 :
UUID=CC70378A703779F2   /media/Recovery ntfs-3g defaults,locale=en_US.UTF-8     0       0
#Entry for /dev/sda5 :
UUID=E6D61DB1D61D834B   /media/Storage  ntfs-3g defaults,locale=en_US.UTF-8,users     0       0
#Entry for /dev/sda7 :
UUID=5e23a31f-95c8-4d0b-ab6c-d34e83fa3a23       none    swap    sw      0       0

Then, you can mount/unmount this drive using

mount /media/Storage      #mount Storage
umount /media/Storage    #unmount Storage


Try running it in protected mode and repair with: apt-get update --fix-missing


How to automatically mount hibernated NTFS to read-only?

First of all, you'll need to find the device id using:

sudo fdisk -l

Look for the one that's formatted as NTFS under System, and remember the device id (Should look something like /dev/sda2). Then create the mount directory and mount it.

mkdir Windows
sudo mount -o ro /dev/sdaX Windows

(Replace X with your device id)


Software Center "Reinstall Previous Purchases" and "Sync Between Computers" not working

For anyone that none of the options are working for, like myself, you can just delete software center using sudo apt-get purge software-center and then sudo apt-get remove software-center and then reinstall using sudo apt-get install software-center. Once you reinstall it, open it and go into file->reinstall previous purchases and make sure that they are asking you to sign into an account to view that. Do not sign into your old account, but rather go to All Software and search steam again. Click Buy and then make a new Ubuntu One account with a new email, verify it, and then the installation process should complete unhindered!


Ubuntu Touch photo transver via Bluetooth

Right now transfer via bluetooth is still not included in Ubuntu Touch. Developers are currently working on it and most probably this feature will be activated with the OTA-10 update which should arrive in March, 2016. See this bug report for details.


How to use the urw chancery font in Libre Office Writer

In Ubuntu 18.04, I just did the following

  Download the .otf or .ttf file.
  Double click on it and click on the green Install button in the Popup.
  (Re)Start LibreOffice and the font should be available in the font menu.

There wasn't any need for any terminal command.


Loop module not present on Ubuntu installation

loop must be compiled into the kernel and not built as a ko module.

That is why it does not appear in lsmod.

You can change max_loop as a boot parameter.

The parameter is called max_loop=255. You can set it in /etc/default/grub in line GRUB_CMDLINE_LINUX_DEFAULT.

Then run sudo update-grub.


Why is Dell XPS 15 9500 wifi card not recognized on Ubuntu 21.04 Hirsute?

New XPS 15 with fresh 21.04 install two weeks ago.
I'm having issues, twice in the past 2 weeks, on my new XPS 15 9500 and 21.04 with wifi working fine initially then not available.  lspci shows the card.
After trying numerous troubleshooting options found online in desperation I usb boot back to 20.10.  wifi isn't available there either.
Reboot to installed 21.04 and mysteriously wifi is back on.
I have no idea if booting into trial 20.10 fixed it or if it is incidental???


Ubuntu 14.04 - No Unity in user account, but in guest account

Open the terminal using (ctrl+alt+T), and try to reset compiz and unity by:

sudo apt-get install dconf-tools
dconf reset -f /org/compiz/
unity-reset
setsid unity

If you are still facing it, then open terminal again and reinstall desktop and unity

sudo apt-get update
sudo apt-get install --reinstall ubuntu-desktop
sudo apt-get install unity


Wine 1.7 not installing on Xubuntu 15.10

The dependency it fails on is libgphoto2-port10, which isn't Wily. You can try manually installing the DEB files from Trusty:

http://packages.ubuntu.com/trusty/libgphoto2-port10


problem in uninstall chrome. i got error so that i could open ubuntu software center too

The PPA you added is not intended for users, only for developers.
You don't need the PPA to install chromium-browser, it is in the standard repository.

You must remove the PPA. Normally this is done through synaptic packet manager but I assume you don't have that installed and you can't install anything at the moment.

in that case you can remove it manually like this:

sudo rm /etc/apt/sources.list.d/a-v-shkop-chromium-dev-precise.list

then clean the packet cache and run the update again:

sudo apt-get clean
sudo apt-get update

then you might like to have the normal chromium-browser from the standard repository:

sudo apt-get install chromium browser

If you encounter any errors, please add them to your question


how to copy files on a differnt ubuntu machine on network to local ubuntu machine

If you type scp you will see this:

usage: scp [-12346BCpqrv] [-c cipher] [-F ssh_config] [-i identity_file]
           [-l limit] [-o ssh_option] [-P port] [-S program]
           [[user@]host1:]file1 ... [[user@]host2:]file2

So, correct syntax is scp file/to/copy username@0.0.0.0:/where/to/copy/

But, to use scp you need to make sure that ssh server is working on host machine. You can try that with simple ssh username@0.0.0.0 where 0.0.0.0 is IP address where you want to connect.


How to use menu (Ubuntu dock) on right screen in 18.04?

One has to set the right screen as primary screen:

The only reason why I didn't see the menu on the right screen immediately, is because one needs to restart the PC or to log off & log in again. Now it works:


sound-juicer does not load CD info from Musicbrainz

What did help was installing ruby-discid package from musicbrainz ppa manually

sudo apt-get remove sound-juicer
sudo add-apt-repository ppa:phw/musicbrainz
sudo apt-get update
sudp apt-get install sound-juicer
sudo apt-get install ruby-discid


How to change field name in LibreOffice Base?

You can't change the table layout (which includes field names) when in table data view. Just close the data view, right-click on the table name and select edit:

This will open the table design view which allows for editing field names:


What's the difference between "history -w" and the action of closing a shell session?

When dealing with Bash history, we have two kinds:

a history list in memory
the .bash_history file on disk

When Bash starts (assuming a default configuration), it will load the contents of your .bash_history file into the history list in memory (after truncating it to the configured size, if necessary).

Then you type your commands which get appended to the history list in memory only. The history file on your disk does not get touched.

Exiting your Bash session regularly (not forcefully killing it or causing it to crash somehow) by default truncates your history list in memory to fit the configured maximum size and then appends only new entries from the current Bash session (because by default the histappend option is enabled) to your history file on the disk, without deleting removed entries or re-adding content from previous sessions.

When you run history -c you clear the complete history list in memory, but again this does not affect the history file on the disk.

Running history -w writes your current history list in memory to the history file on disk. It does not append new entries but overwrites the complete file. Therefore running history -c && history -w effectively clears the history file as well.

Manually clearing your history file by editing it from within a running Bash session has not the expected effect or permanently deleting the entire history so far, because the history list in memory which still contains all old entries from the history file will stay intact.

On exiting your Bash session, the history file will get rewritten with the data from the history list. However, as by default the histappend option is enabled, only new entries from the current Bash session will be written to the file, older history data gets discarded. You would have to run history -w to save the full history list to disk.

What exactly happens when a Bash shell starts and exits can be read in man bash:

HISTORY
       When the -o history option to the set builtin  is  enabled,  the  shell
       provides access to the command history, the list of commands previously
       typed.  The value of the HISTSIZE variable is used  as  the  number  of
       commands to save in a history list.  The text of the last HISTSIZE com‐
       mands (default 500) is saved.  The shell stores  each  command  in  the
       history  list  prior to parameter and variable expansion (see EXPANSION
       above) but after history expansion is performed, subject to the  values
       of the shell variables HISTIGNORE and HISTCONTROL.

       On startup, the history is initialized from the file named by the vari‐
       able HISTFILE (default ~/.bash_history).  The file named by  the  value
       of  HISTFILE  is  truncated,  if necessary, to contain no more than the
       number of lines specified by the value of HISTFILESIZE.   If  HISTFILE‐
       SIZE  is unset, or set to null, a non-numeric value, or a numeric value
       less than zero, the history file is not truncated.   When  the  history
       file  is  read, lines beginning with the history comment character fol‐
       lowed immediately by a digit are interpreted as timestamps for the pre‐
       ceding history line.  These timestamps are optionally displayed depend‐
       ing on the value of the HISTTIMEFORMAT variable.   When  a  shell  with
       history  enabled  exits,  the  last $HISTSIZE lines are copied from the
       history list to $HISTFILE.  If the histappend shell option  is  enabled
       (see  the description of shopt under SHELL BUILTIN COMMANDS below), the
       lines are appended to the history file, otherwise the history  file  is
       overwritten.   If  HISTFILE  is  unset,  or  if  the  history  file  is
       unwritable, the history is not saved.  If the  HISTTIMEFORMAT  variable
       is  set,  time  stamps are written to the history file, marked with the
       history comment character, so they may be preserved across  shell  ses‐
       sions.   This  uses  the history comment character to distinguish time‐
       stamps from other history lines.  After saving the history, the history
       file is truncated to contain no more than HISTFILESIZE lines.  If HIST‐
       FILESIZE is unset, or set to null, a non-numeric value,  or  a  numeric
       value less than zero, the history file is not truncated.


How to change the guest session keyboard layout?

Actually as far as I know , You can't do that , You can have 2 user accounts and each one with a different keyboard style , But a Guest doesn't get those settings and a user can't change then , Most likely you can do it in the Terminal with UNIX commands or GRUB but I am not a expert with that , Sorry I can not help that much but the easiest way is making a a Guest User Account on it and limiting the things it can do , Not making it an admin , And putting a password only you can know


Using ubuntu classic window manager from USB drive

Okay. I found a way to do it. From the power icon on the right, there is a "switch from ubuntu..." menu. Use that to logout. On the login screen, login with username "ubuntu" and password as blank.


Upgraded to Ubuntu 16.04. Extremely slow boot now. Any suggestions?

Well I fixed it. My /etc/fstab file had the wrong uuid for the swap partition so it was looking for something that did not exist.

I used Disks to see in what partition it was in and then

sudo blkid /dev/sda6

to get the correct uuid and changed it on my fstab


I don't know why you're trying to replace systemd-resolved, but if you need to run them at the same time...

Regarding dnsmasq and systemd-resolved...

Do a ps auxc | grep -i dns and ps auxc | grep -i resolv and look for dnsmasq and systemd-resolved, and if both are running, you need to disable the DNS part of systemd-resolved by editing /etc/systemd/resolved.conf and...

change:

#DNSStubListener=yes

to:

DNSStubListener=no

then restart systemd-resolve and dnsmasq, or reboot.

You need to reset the symlink that is /etc/resolv.conf

sudo mv /etc/resolv.conf /etc/resolv.conf.OLD # save the old symlink

sudo ln -s /run/resolvconf/resolv.conf /etc/resolv.conf


Screen is black; Mouse cursor doesn't move

Press and hold ALT+PRINT and type (while holding) R E I S U B. This will restart your machine.


juju error: certificate expired/not-valid

The problem was fixed by setting the time zone of the machine/n to be same as MAAS server


20 gig is more sufficient for an Ubuntu installation.  If you need more space for a directory like /home, /opt, /srv or /var, you can move these to a new partition and mount it over the directory.

If you need more space for a Windows partion, you may be able to use a tool like partionmanager to resize the partition.  You will need to install the package before using it.  However, if you have a failed installation, you may want to delete and recreate the partition with the proper size.

EDIT: There are lots of guides to adding a new partition to linux such as this one.  Moving /var is likely the best bet to move first.

The command apt-get clean should free up a fair bit of space fairly quickly.  It will remove the file used to install the packages.   Often apt-get autoclean will free up a fair bit of space by removing outdated package downloads.


SSH - How to force execution of a script ( /etc/sshrc , ForceCommand, .. ? ) on login but still allow execution of the client's ~/.ssh/rc?

The solution seems to be to evaluate the

  SSH_ORIGINAL_COMMAND

environment variable that gets set to the command in the client's ~/.ssh/rc inside the script configured as ForceCommand.

I found this possible solution in this answer.

Remaining: Is there a way to override the ~/.ssh/rc location using an environment variable?


How can I make another pdf viewer default for pdf files?

You can right-click on a .pdf file, then go to 'Properties' --> 'Open with' tab and select the application that you want.


Media players & KDE Connect multimedia control

By the KDE Connect /1, 2, 3/ mailing list the KDE Connect supports mediaplayer if they implement the MPRIS /4, 5/ interface.

By the KDE Connect mailing list /6/ there should be a MPRIS2 interface plugin for the DeaDBeeF /7/.

Links

https://community.kde.org/KDEConnect
https://mail.kde.org/mailman/listinfo/kdeconnect
https://mail.kde.org/pipermail/kdeconnect/2016-September/001646.html
https://community.kde.org/MPRIS
https://www.freedesktop.org/wiki/Specifications/mpris-spec/
https://mail.kde.org/pipermail/kdeconnect/2016-September/001648.html
https://github.com/Serranya/deadbeef-mpris2-plugin

Therefore, you have to see if the MPRIS interface can be enabled or added to the player as an extension or plugin.

Qmmp has the mpris plugin, but it is disabled by default and needs to be enabled under Settings-Plugins-General section:

MPV video player can also get KDE Connect-ed (as described here) like so: download the mpris plugin from here (64bit-only), copy the mpris.so file into the directory ~/.config/mpv/scripts, restart session.

Clementine is by default accessible through KDE-Connect; it is qt-based and widely popular.

QMPlay2 is another multimedia player that is supported. The Mpris2 plugin is enabled by default in "Settings->Modules->Extensions" (I had to disable and re-enable it to make it work though).


Try these commnds :

sudo apt-get clean && sudo apt-get update
sudo apt-get upgrade

Then try re installing and see if it works..

And the other option is that, you may download the latest version from VLC official Site


I discovered that I had to download the version from Mozilla instead of using the repository; that required copying the extracted directory to /opt/firefox67.0.4, and creating a new symbolic link in usr/bin/firefox to /opt/firefox67.0.4/firefox.  The new version would not recognize my existing profile; if I tried to use the existing profile, Firefox would refuse to load.  I finally had to copy places.sqlite to the new profile, then reinstall my add-ons.


How to remove KDE PIM modules from Kubuntu 18.04

In Bionic Beaver (18.04), a minimal install option is offered to users. Ubuntu, Ubuntu Mate, and Kubuntu are three distributions I know of that offer the option.

For Kubuntu 18.04, you'll see this (taken from here):

The release notes for Kubuntu 18.04 have this:

  Minimal install option
  This is now available in the installer for Kubuntu.

  For Kubuntu this removes KDE PIM applications, Libreoffice, Cantata and mpd, plus some additional internet and media applications. At present a full Plasma Desktop is left in place, plus basic applications and utilities. Firefox as a browser, and VLC as a media player, are also retained.

A list of what is not included in the minimal install relative to the full install is here. I can't say how up to date the list is but there's a section on KDE PIM to provide you guidance in case you want to remove stuff from an existing full install.

# KDE PIM

accountwizard
akonadi-backend-mysql
akonadi-server
akregator
kaddressbook
kdepim-addons
kdepim-runtime
kdepim-themeeditors
kleopatra
kmail
knotes
kontact
korganizer
ktnef
mbox-importer
pim-data-exporter
pim-sieve-editor

I've checked some of the entries above using apt purge -s package-name. Each of the packages I checked only removed the named package and nothing else.

There's also a section titled residual deps/reverse-deps.

# residual deps/reverse-deps

ktorrent-data
konversation-data
mysql-client-core-5.7
mysql-server-core-5.7
kde-config-mailtransport
kf5-kdepim-apps-libs-data
kf5-messagelib-data
kio-ldap
kio-sieve
libkf5akonadiagentbase5
libkf5akonadicalendar5abi2
libkf5akonadicalendar-data
libkf5akonadicontact5abi1
libkf5akonadicontact-data
libkf5akonadicore5abi1
libkf5akonadicore-bin
libkf5akonadimime5
libkf5akonadimime-data
libkf5akonadinotes5
libkf5akonadinotes-data
libkf5akonadiprivate5
libkf5akonadisearch-bin
libkf5akonadisearchcore5
libkf5akonadisearch-data
libkf5akonadisearchdebug5
libkf5akonadisearchpim5
libkf5akonadisearch-plugins
libkf5akonadisearchxapian5
libkf5akonadiwidgets5
libkf5alarmcalendar5abi1
libkf5alarmcalendar-data
libkf5calendarcore5abi1
libkf5calendarsupport5abi1
libkf5calendarsupport-data
libkf5calendarutils5abi1
libkf5calendarutils-bin
libkf5calendarutils-data
libkf5contacteditor5
libkf5contacteditor-data
libkf5contacts5
libkf5contacts-data
libkf5eventviews5
libkf5eventviews-data
libkf5followupreminder5
libkf5grantleetheme5
libkf5grantleetheme-data
libkf5grantleetheme-plugins
libkf5gravatar5
libkf5gravatar-data
libkf5identitymanagement5abi1
libkf5identitymanagement-data
libkf5imap5
libkf5imap-data
libkf5incidenceeditor5abi2
libkf5incidenceeditor-bin
libkf5incidenceeditor-data
libkf5kaddressbookgrantlee5
libkf5kaddressbookimportexport5
libkf5kdepimdbusinterfaces5
libkf5kmanagesieve5
libkf5kontactinterface5
libkf5kontactinterface-data
libkf5ksieve5
libkf5ksieve-data
libkf5ksieveui5
libkf5ldap5
libkf5ldap-data
libkf5libkdepim5abi2
libkf5libkdepimakonadi5
libkf5libkdepim-data
libkf5libkdepim-plugins
libkf5libkleo5abi1
libkf5mailcommon5abi4
libkf5mailcommon-plugins
libkf5mailimporter5abi1
libkf5mailimporterakonadi5
libkf5mailimporter-data
libkf5mailtransport5abi2
libkf5mailtransportakonadi5
libkf5mailtransport-data
libkf5mbox5
libkf5messagecomposer5abi2
libkf5messagecore5abi2
libkf5messagelist5abi1
libkf5messageviewer5abi4
libkf5messageviewer-plugins
libkf5mime5abi2
libkf5mime-data
libkf5mimetreeparser5abi2
libkf5pimcommon5abi3
libkf5pimcommonakonadi5
libkf5pimcommon-plugins
libkf5pimtextedit5abi2
libkf5pimtextedit-data
libkf5sendlater5
libkf5syndication5
libkf5templateparser5abi2
libkf5tnef5
libkf5tnef-data
libkf5webengineviewer5abi3
libkpimgapicalendar5
libkpimgapicontacts5
libkpimgapitasks5
libkpimimportwizard5
libkpimkdav5
libkpimkdav-data

It's also useful to run akonadictl status to what see akonadiis up to on your system. On my system, I see:

$ akonadictl status
Akonadi Control: stopped
Akonadi Server: stopped
Akonadi Server Search Support: available (Remote Search)
Available Agent Types: akonadi_akonotes_resource, akonadi_archivemail_agent, akonadi_birthdays_resource, akonadi_contacts_resource, akonadi_davgroupware_resource, akonadi_ews_resource, akonadi_ewsmta_resource, akonadi_facebook_resource, akonadi_followupreminder_agent, akonadi_googlecalendar_resource, akonadi_googlecontacts_resource, akonadi_ical_resource, akonadi_icaldir_resource, akonadi_imap_resource, akonadi_indexing_agent, akonadi_invitations_agent, akonadi_kalarm_dir_resource, akonadi_kalarm_resource, akonadi_kolab_resource, akonadi_maildir_resource, akonadi_maildispatcher_agent, akonadi_mailfilter_agent, akonadi_mbox_resource, akonadi_migration_agent, akonadi_mixedmaildir_resource, akonadi_newmailnotifier_agent, akonadi_notes_agent, akonadi_notes_resource, akonadi_openxchange_resource, akonadi_pop3_resource, akonadi_sendlater_agent, akonadi_tomboynotes_resource, akonadi_vcard_resource, akonadi_vcarddir_resource
$

And man akonadictl has

stop   : Stops the Akonadi server and all its processes cleanly

which you may find useful.

Another useful command is compgen:

$ compgen -c | grep mysql
mysqld
mysqld-akonadi
mysql
mysql_upgrade
mysql_install_db
mysql_embedded
mysqlcheck
$

On my system, both pgrep -i -al akonadi and pgrep -i -al mysql come up empty.


Ubuntu 13.10, format the entire harddrive and install Windows 8.1

Grub will be erased after formatting.

Windows boot manager will be reinstalled after Windows installation.

Windows will automatically boot into windows and will not see any other OSs.