Why are the 'same' executables in `/usr/bin/` and `/usr/bin/X11/`? Are they really the same?

Once upon a time there was no GUI. And when the X Window System appeared, it came with wondrous graphical programs such as xterm and xclock and so on, and with utilities such as xrdb and xmodmap. And people used to put those graphical programs in a special directory, which in time became /usr/bin/X11. (X11 because the the final version of the X Protocol is 11, specifically X version 11 release 6 point 4, X11R6.4; before X11 there were and X9 and an X10.)

But nowadays all executables live in /bin and /usr/bin and /sbin and /usr/sbin; while /usr/bin/X11 serves no purpose any longer, it is still created as a symbolic link to /usr/bin in order to keep compatibility with old sysadmins and old scripts, which are used to xterm being /usr/bin/X11/xterm.

So the answer is that it is not the executables which are the same in /usr/bin and /usr/bin/X11: it is /usr/bin/X11 itself which is the same as /usr/bin.

If you look you will notice that /usr/bin/X11 is a symlink to .. This is called a relative symlink: /usr/bin/X11 being a file in /usr/bin and a symlink pointing to the current directory, ., this makes /usr/bin/X11 a synonym for /usr/bin.


Permanently change system color temperature

Hacky way, but that's all I can come up with it.

Install redshift-gtk

sudo apt install redshift-gtk

Create .config/redshift.conf file in your home directory with the following content. Add redshift-gtk to the startup.

; Global settings for redshift
[redshift]
; Set the day and night screen temperatures
temp-day=3000
temp-night=3000
location-provider=manual

[manual]
lat=11.11
lon=22.22


vmpk is a virtual MIDI Master keyboard, and does not produce any sound.  To generate sound, you must

connect the MIDI output from vmpk to the MIDI input of some tone generator (e.g. qsynth).  If you then
connect the audio output from the tone generator to the audio input for your monitors,

you should hear some sounds.

In your specific situation, where you want to use vmpk, qsynth, and jack control, I would recommend the following procedure to generate audio based on virtual keystrokes:

Install the "patchage" and "fluid-soundfont-gm" packages
Open Jack Control
Review JACK configuration to ensure it is attached to your preferred audio interface
Start JACK (the big play button)
Open Patchage
Open vmpk
Open Qsynth
In patchage, connect vmpk MIDI out to Qsynth MIDI in
In patchage, connect Qsynth audio out to your audio interface (both left and right channels)
In Qsynth, load a soundfont from /usr/share/sounds/sf2/FluidR3_GM.sf2
Virtually press any key in vmpk to hear sound

Although the specific tools in use differ slightly, you may find the guidance at Ubuntu Wiki helpful.  The primary difference is that you will be using a virtual keyboard rather than a physical keyboard, but patchage should not be able to tell the difference.


This will require a Live Ubuntu Media (CD/DVD/USB, the same you used to install Ubuntu). Boot from it in the "Try without installing" option. Open a terminal windows and run the following commands:

sudo mount /dev/sdaX /mnt

replacing X with your Ubuntu's partition number.

sudo grub-install /dev/sda --root-partition=/mnt
sudo chroot /mnt
sudo update-grub
exit

Reboot and GRUB should be OK.


Using apropos we can see what app is used for the next boot only:

$ apropos "next boot only"
grub-reboot (8) - set the default boot entry for GRUB, for the next boot only

With using grub-reboot for a one-time boot, I have found that it is best to use the name of the entry and not the number of the entry like some of the linked answers here have had.  I just cannot get it to work with the numbers of the entries.  Here is something that I have found works with using the names of the entries.

If you cat the /boot/grub/grub.cfg there are a lot of entries that we are looking for.  The one in particular is the Memory test entry.

$ grep -i "memory test" /boot/grub/grub.cfg
menuentry 'Memory test (memtest86+)' {
menuentry 'Memory test (memtest86+, serial console 115200)' {

Since all we need is just the first entry and we need the full name of Memory test (memtest86+) to tell the grub-reboot that is what we need, we can use the following line to grab only that name and the first entry, specified by the exit command.

awk -F"'" '/Memory test/ {print $2; exit}' /boot/grub/grub.cfg

Which gives us output like:

$ awk -F"'" '/Memory test/ {print $2; exit}' /boot/grub/grub.cfg
Memory test (memtest86+)

Now we can combine that line into our one line command to reboot our system to Memtest as a one-time boot.

sudo grub-reboot "$(awk -F"'" '/Memory test/ {print $2; exit}' /boot/grub/grub.cfg)"; reboot

The reboot part at the end will go ahead and reboot your system for now.

Hope this helps!


Dumping a list of corrupt video files & quality

I'm not sure about the behaviour of corrupt video files. I'll just give suggestions for possible behaviours.

Will these files not play at all? Or will the playback crash somewhere in the middle of the movie?

If it is the former, you can try mplayer -vo null -ao null on a file, make sure that mplayer doesn't quit in the first 2-3 seconds, kill mplayer and move to the next. Should be easy enough to script and shouldn't take more than an hour for 1000 movies.

If it is the latter, again there are two possibilities.

mplayer cannot seek to any position beyond the crash point.
mplayer can seek to a position beyond the crash point and play smoothly.

Case 1 can be handled by opening a file with echo 'seek 95 1' | mplayer -vo null -ao null -slave and checking if mplayer crashes. This command just opens the file and tries to seek to 95% time position.

Case 2 means that a crash cannot be detected by looking at any point of the file other than the crash point. So, the only way to go about it will be to decode the entire file and see if the decoding fails at some point. There are ways to decode files faster than real time playback, but still I'd expect this process to go on for days, possibly months. It's up to you to decide whether detecting 20-30 corrupt files among a few thousand is really worth this much effort.

Detecting videos that aren't 720p:

mplayer file.extn -frames 0 -vo null -ao null 2> /dev/null | grep VIDEO | awk '{ print $3 }' prints the resolution of the video. You can use this to generate the required list.


tightvnc is not working properly..its showing grey background with X cursor

There is a major bug with tightvnc and 13.10 you can read about it here


Everything from the 'main' repository has 5 years of support, you cannot load xubuntu-desktop (or any other desktop) from 'main' as it comes from 'universe' (community supported), so those packages are not supported with the five years of support.

Downloading Xubuntu does include packages with 5 years of support, but it's ALL covered by 3 years of LTS support (only some packages have the longer support life).  We know parts have longer support, but it's a potential risk to use a system only partially supported, so it's safer to treat is as a 3 year fully-supported product (as advertized).

Refer to https://help.ubuntu.com/community/Repositories/Ubuntu for information on repositories & software-sources.

The moment you add PPA's you've made your system more complex (you do the security checks for PPAs yourself, and have to check your support completely yourself as some have no support).

The initial 'full-support' guarantee applies only to what's on the install-media (which may differ the moment you starting adding new sources). Ubuntu has 5 years of support for everything on install media, where as flavors have the shorter (usually 3 years) support.


What is removing files under /tmp on an ~hourly basis?

Since there's no information what OS/Version you are using, my best bet would be

systemctl status systemd-tmpfiles-clean.timer
systemd-tmpfiles-clean.timer - Daily Cleanup of Temporary Directories


Internet connection not working in Ubuntu 15.04

I have often faced issues with Networks in Ubuntu.

Some of the solutions which may help you:

Network manager indicator missing
Try restarting the network manager with:

sudo service network-manager restart

Network devices unmanaged after resume from hibernation in Ubuntu Gnome 13.10

Another possible issue could be that the driver is not installed, in which case you would need to go to "Additional Drivers" and install the appropriate driver.
For more details on that you can refer here:
How do I install additional drivers?


Ubuntu 15.04 : Green spots during video playback

Tools -> Preferences -> Video -> Display

Uncheck "Accelerated Video Output(Relay)" as mentioned here


Error: .ini file does not include supervisorctl section

Adding a blank [supervisorctl] section seems to resolve the issue for me:

$ cat /etc/supervisor/supervisord.conf
[supervisord]
nodaemon=true

[supervisorctl]


It's likely the resources issue: out of memory. When Ubuntu runs our of memory, the OOM killer kicks in and kills some processes until it has enough memory again. If your program consumes loads of memory, perhaps there is a bug in it. (e.g. it would not make sense to take 500MB for reading a PDF.) Sometimes, other programs are responsible for eating memory. On KDE, kmix and knotify4 is known to use a lot memory under certain conditions wihout giving it back. To solve that, I've a cron running restarting these processes use excess memory.

Solution: upgrade your RAM and/ or add more swap. More RAM will definitely help more, swap is much slower and just delays the death of your application.


19.10: Change loading screen background color

I believe you are talking about the Plymouth screen that appears before the login screen appears.

This has already been answered here.
How can I change the purple background color of Ubuntu plymouth boot screen?

Inside of this file /lib/plymouth/themes/ubuntu-logo/ubuntu-logo.script

Change these values.

Window.SetBackgroundTopColor (0.0, 0.00, 0.0);
Window.SetBackgroundBottomColor (0.0, 0.00, 0.0);

Then run.

sudo update-initramfs -u


Ubuntu 11.10 wont' upgrade to Firefox 21

11.10 has reached its EOL (End Of Life) and you won't get any upgrades for it. You have to upgrade to another version of Ubuntu.


It doesn't sound like the BIOS is fully setup when it goes through PXE boot. ACPI (provides suspend/resume + hotkeys ...) must be partially working because you were able to suspend, but when it's asked to resume, it's decided not to run the video card's option rom, if it even got that far.

To confirm that the system is resuming but you have no video, setup a serial console (or just ssh) and try again. If it does resume, you can start X windows which will "soft boot" the video card and maybe get your video back.

If you get no serial console then either the kernel is broken or the BIOS is broken. To help isolate, install 'fwts' and run the suspend/resume test. fwts uses an alarm timer provided by the platform to trigger itself to resume after N seconds. If it can't do that then you have deep platform issues to address.

If it can do that, you still have deep platform issues to address because it means the interrupts sent by the keyboard are going into la la land instead of getting ACPI to do it's job. However, you could leverage fwts to unfreeze the drive, script it, and shutdown when you're done.

Back to the frozen SSD issue. If you could unload/reload the module that would force a link reset on the HBA. Less satisfying approaches include using sysfs to delete the drive and then rescan the bus. I don't think that performs a link reset. You may be able to use sg_reset to whack the drive, I would just reset the whole bus.

Sometimes there's just no substitute for a hard disk cage with bay level power control.


How to retrive a single file from github using git

You can get that file using wget:

Create a directory:
 mkdir mypycode

Change into that directory:
 cd mypycode

Identify the raw URL

Navigate to your file on github (or your git host)
Click on the Raw tab.

Use wget to download it:
 wget https://raw.githubusercontent.com/tensorflow/tensorflow/r1.1/tensorflow/examples/tutorials/mnist/mnist_softmax.py


In Ubuntu an URL shortcut is stored in a .desktop file as follow (for example):

[Desktop Entry]
Encoding=UTF-8
Name=Link to Best Practices Software engineering
Type=Link
URL=http://abdennour-insat.blogspot.com/
Icon=text-html

If you still want to open your Windows URL files in Ubuntu, here is described how you can do it:

How to Open .url Internet Explorer Shortcuts in Ubuntu Using Firefox.

The Perl script given in that article appears to be broken, but the following code should do the same thing correctly:

#!/usr/bin/perl
# Script to make Microsoft Windows Internet Shortcuts (*.url) work on Linux.

my $browser = 'sensible-browser';  # use the system default browser

while (<>) {
    # match any line of the form "URL = something-without-spaces"
    if (/^\s*URL\s*=\s*(\S+)\s*$/) {
        exec $browser, $1;         # successful exec never returns
        die "$0: could not launch $browser: $!\n";
    }
}


Can I use the Copy app to sync the home folders of two PCs together?

Yes, as that is what I do.

I'll assume that on your first computer, your files are in ~/Documents, ~/Pictures etc and you've created symbolic links to ~/Copy/Documents, ~/Copy/Pictures.

On your second computer, synchronise your Copy folder with the cloud (or copy it across using network/USB etc), and then create the symbolic links from ~/Copy/Documents etc to ~/Documents

Job done :)


Ubuntu 14.04 can't get nvidia-prime working

Here is a variant of the above, and a solution - for THIS case, possibly helping in the other cases too.

SIDENOTE 1: if you do not run nvidia-settings with gksudo ... THE FIRST TIME (and do not have "$HOME/.config/ibus/" at that time) you will end up seeing:
IBUS-WARNING **: The owner of /home/$USER/.config/ibus/bus is not root!
Then refer back to http://ubuntuforums.org/showthread.php?t=2140352 - then delete the .../ibus/ directory (note NOT .config/) and continue here...

SIDENOTE 2: you may also see:
** (nvidia-settings:8563): WARNING **: PRIME: Failed to execute child process "/usr/bin/prime-supported" (No such file or directory)
** Message: PRIME: is it supported? no
The remedy is to do

sudo apt-get install nvidia-prime
... which was BROKEN for some time, but seems to be back "online" again.

SIDENOTE 3: Unless you have e.g. DUMMY like this:
$ tail -n 3 /etc/group
nvidia-persistenced:x:128:

DUMMY:x:65535:

(hrm, that is three lines, even if doesn't look like it) ... then you will NOT have color-profiles loaded for your EXTRA displays - in a multi-display setup - on startup. The problem is the LAST LINE in /etc/group - that group will not "work".

The following has a direct relation to not being able to save changed settings:

$ gksudo nvidia-settings

ERROR: nvidia-settings could not find the registry key file. This file should have been installed along with this driver at either /usr/share/nvidia/nvidia-application-profiles-337.25-key-documentation or
       /usr/share/nvidia/nvidia-application-profiles-key-documentation. The application profiles will continue to work, but values cannot be preopulated or validated, and will not be listed in the help text. Please see the README for possible
       values and descriptions.

... is that familiar? Then do

sudo bash
...
mkdir -p /etc/nvidia
cd /etc/nvidia
ln -s /etc/alternatives/x86_64-linux-gnu_nvidia_app_profile_keys  nvidia-application-profiles-340.24-key-documentation
ln -s /etc/alternatives/x86_64-linux-gnu_nvidia_app_profile  nvidia-application-profiles-340.24-rc

Then check that you can see something similar to:

$ ls -l
total 0
lrwxrwxrwx 1 root 58 jul 12 14:23 nvidia-application-profiles-340.24-key-documentation -> /etc/alternatives/x86_64-linux-gnu_nvidia_app_profile_keys
lrwxrwxrwx 1 root 53 jul 12 14:23 nvidia-application-profiles-340.24-rc -> /etc/alternatives/x86_64-linux-gnu_nvidia_app_profile

Note that "-340.24..." and maybe other parts may differ for you (depending on version of the driver), what is shown is after installing the very latest from the xorg-edgers ppa at this writing.


If you have imported it the right way (New Calendar => Type Google), you can remove it right-clicking on the calendar name and then deleting it.
If you have imported a CVS/ICS calendar file (Google calendar => Export),  this approach doesn't work.


What is the proper way of creating installation media from Ubuntu iso?

This flowchart shows how to make a bootable USB for installing Ubuntu and troubleshoot problems booting Ubuntu from it.

Links

How to create a bootable USB stick on Windows
Ubuntu on 32-bit UEFI-based tablet PC
Need help regarding dd command on Ubuntu app for Windows 10

How to make an Ubuntu USB on Ubuntu using Startup Disk Creator
Ubuntu has a built-in application for creating a bootable Ubuntu live USB for installing Ubuntu called Startup Disk Creator. Search the Dash for Startup Disk Creator and click the Startup Disk Creator icon to open the Make Startup Disk window.
The USB flash drive that you use with Startup Disk Creator should be 2GB or larger, and for Ubuntu 18.04 and later it should be 4GB or larger. Startup Disk Creator will automatically format your USB flash drive to FAT32 and make it bootable. If you have only one USB flash drive plugged in to your computer, Startup Disk Creator will select it automatically. Be very careful to select the USB flash drive in the Make Startup Disk window in order to avoid overwriting the partition which Ubuntu is installed on, which may make Ubuntu unbootable. In the screenshot below you can see how the USB flash drive Device is identified by its model name, the same model name that appears under the Drive heading after Model: in the Disks (disk utility) application.

Startup Disk Creator in Ubuntu 16.04
How to make an Ubuntu Minimal USB using dd
While the minimal iso image is handy, it isn't useful for installing on UEFI-based systems that you want to run in UEFI mode. The mini iso lacks the proper files for booting the computer in UEFI mode. Thus the computer will boot in BIOS compatibility mode, and the installation will be in BIOS mode.

Download the Ubuntu Mini CD iso file for Ubuntu 18.04 and earlier from the link on the Ubuntu Documentation Installation Minimal CD webpage. Download the Ubuntu Mini CD iso file for Ubuntu 20.04 from http://archive.ubuntu.com/ubuntu/dists/focal/main/installer-amd64/current/legacy-images/netboot/mini.iso. Download the file called mini.iso to your Downloads folder. You can download the mini.iso file to wherever on your computer that you want, but download it to your Downloads folder so that you can easily run the commands in the following steps without changing anything.

Verify the md5 checksum of the Ubuntu mini CD iso file that you downloaded by running these commands:
cd ~/Downloads/
md5sum 'mini.iso'

If you are using Windows Subsystem for Linux download the Microsoft File Checksum Integrity Verifier tool from the official Microsoft Download Center. The Microsoft File Checksum Integrity Verifier tool is a command line utility that computes MD5 or SHA1 cryptographic hashes for files.

Check that the results of the command match the MD5 checksum of the mini.iso file on the Ubuntu Documentation Installation Minimal CD webpage.

Get a USB flash drive, 1GB or larger. Delete all the files from the USB flash drive. Mount the flash drive using the Disks disk utility.

Check in the Disks disk utility to find out the device name of your USB flash drive. This is very important because if you use the wrong device name in step 6, you will overwrite your whole operating system instead of writing to the USB flash drive. So check the USB flash drive device name twice.  It should be something like /dev/sd* where instead of the * character there is a lower case letter like a, b, c, etc. In the following step I am assuming that the device name is /dev/sdc, but the device name of your USB drive could be something else like /dev/sda or /dev/sdb so check the device name of your USB drive twice and make sure that you get it right in step 6!

Open the terminal or Windows Subsystem for Linux 2 and run the following commands:
cd ~/Downloads/
sudo -i
dd if='mini.iso' of=/dev/sdc bs=4096  ## make sure that the device name of your USB drive is correct!

The dd if='mini.iso' of=/dev/sdc bs=4096 command should take only a few seconds to complete on most computers because the mini.iso is a small file, less than 60MB. The result of running this command will be a bootable Ubuntu mini USB.

Boot the computer from the Ubuntu mini live USB. The Ubuntu mini live USB should boot successfully and show a menu screen.

If you select the Install option (the complete install, not the cli install) from the menu screen in Step 7, then you can select other options during the Ubuntu installation process to download all the packages that you need to perform a complete Ubuntu installation. Select the Ubuntu desktop package collection from the list of predefined collections of software in the Software selection screen in the Ubuntu mini CD installer. When you restart the system at the end of the installation, you will have a working Ubuntu desktop with the default desktop environment.


how to install Pantheon desktop environment on Ubuntu 20.04?

The stable branch does not have 20.04 available yet (Dec. 2020)
You can install the daily builds using the daily PPA.
Here's a good write up on desktop environments for 20.04 (includes Phanteon)
https://itsubuntu.com/top-desktop-environments-for-ubuntu-20-04-lts/


I was able to figure this out. The SuperSU app was not installed properly so the phone was not properly rooted. I used another app to root the device and the installation went successfully.


The problem has already been reported to Ubuntu at the link you provided, so nothing more needs to be done there just yet.

If SWT_GTK3=0 works well, you should set it as unglobally as is feasible. There are a few ways to do it (choose the last one that will work for your situation):

/etc/environment applies to everything for every user, not just Java programs
/etc/bash.bashrc applies to things started from bash for every user, not just Java.
~/.bashrc applies to things started from bash for the current user, not just Java.
The following will apply to things started from bash for every user using the java command. Press Ctrl+Alt+T and run the following:

    sudo -i
    mkdir -p /usr/local/bin
    echo '#!/bin/sh' > /usr/local/bin/java
    echo 'SWT_GTK3=0 /usr/bin/java $*' >> /usr/local/bin/java
    chmod a+x /usr/local/bin/java
    exit
    exit

The following will apply to things started from bash for the current user using the java command. Press Ctrl+Alt+T and run the following:

    mkdir -p ~/bin
    echo '#!/bin/sh' > ~/bin/java
    echo 'SWT_GTK3=0 /usr/bin/java $*' >> ~/bin/java
    chmod a+x ~/bin/java
    exit


How do I merge a number of documents into one pdf in the pdf printer

you can use PDF Split and Merge for that. Search for it in the Software Center or open a terminal (Ctrl+Alt+T) and type

sudo apt-get install pdfsam

After that you can open the GUI version and merge/split PDFs with it. You can also use the terminal like this:

pdfsam-console -f input1.pdf -f input2.pdf -o output.pdf concat


Switching language and the subsequent input of capital letters

I have the same problem. It's very uncomfortable. I filed a bug report on bugtracker: https://bugs.launchpad.net/ubuntu/+bug/1797389. I found a solution to this problem. The problem was with Xorg.

Add this repository: ppa:nrbrtx/xorg-hotkeys

sudo add-apt-repository ppa:nrbrtx/xorg-hotkeys

Upgrade the system.

sudo apt update && sudo apt upgrade

Reboot.

sudo reboot


Trouble compiling GDB with python 2.7 support for gdb-peda

An easier way to install gdb with Python 2.7 support is:

sudo apt-get remove gdb
wget http://security.ubuntu.com/ubuntu/pool/main/g/gdb/gdb_7.4-2012.02-0ubuntu2_amd64.deb
sudo dpkg -i ./gdb_7.4-2012.02-0ubuntu2_amd64.deb

Substitute i386 for amd64 if necessary.

The first line removes the current gdb version. The second will download gdb from a previous version. And the last line installs it.


How do I determine if my integrated Intel graphics support "Shader Model 3"?

You can run

glxinfo | grep OpenGL

shading language version string will show you version of shaders.

E.g.

OpenGL shading language version string: 4.60 NVIDIA

Your system doesn't support shaders version 3.


How do I check which terminal I am using?

TL;DR

to find currently running shell use ls -l /proc/$$/exe
to find currently running terminal, use xprop _NET_WM_PID WM_CLASS. The value of pid later can be passed to ps -p <pid> -o args command.
Technically, for terminal emulator you don't even need a command, as stated in the comments:

  what do you mean by which? Click Help --> About is that it? – JoKeR

Shell vs Terminal

First thing we need to have clarified is what exactly is being asked - find out the running shell or running terminal. Often these two terms are used interchangeably, but they are different things altogether. Shell is the command-line interpreter, specifically interactive shell is the prompt plus text field where you enter commands. Shells can also be non-interactive, for example a script starts non-interactive shell, or bash -c 'echo hello world' also starts non-interactive shell.

By contrast, terminal is the interface to shell ( though it could be another application as well). Originally terminal referred to actual hardware, but nowadays they're mostly software. What you see when you press Ctrl+Alt+t or click on the terminal icon in GUI, that starts a terminal emulator, a window which mimics behavior of hardware, and within that window you can see the shell running. Ctrl+Alt+F2 (or any of the 6 function keys) will open virtual console, aka tty. I recommend reading Why is a virtual terminal “virtual”, and what/why/where is the “real” terminal? for more info on the specifics.

Getting the shell information

Each user has a default shell assigned to them in /etc/passwd for their username. Assuming you are using default configuration and haven't called another shell explicitly as a command, it is sufficient to do:

echo $SHELL

But of course this only shows default value. Suppose we do the following:

user@ubuntu:~$ dash
$

We were originally in bash, but started interactive session of /bin/dash, Ubuntu's POSIX or system shell. The variable $SHELL won't change,  because that's not its purpose - it shows default not current value. We will need to approach this from another perspective - the perspective of a process, which is something I've covered in Am I using bash or sh?

$ echo $$
4824
$ cat /proc/4824/comm
mksh
$ bash
xieerqi@eagle:~$ echo $$
6197
xieerqi@eagle:~$ cat /proc/6197/comm
bash

Here we take advantage of /proc/ filesystem. The name of the process and command-line parameters are displayed in /proc/<pid>/comm. All we need is to provide shell's PID, which is what $$ does. In the example above I am adding that separately, but there is nothing stopping us from doing just

cat /proc/$$/comm

Variation on the theme could also be

ps -p $$ -o args

Another way we could approach this is via checking where /proc/<pid>/exe. This file is a symlink that points to the executable file. Thus we can do

user@ubuntu:~$ ls -l /proc/$$/exe
lrwxrwxrwx 1 adminx adminx 0 Apr  4 18:20 /proc/1241/exe -> /bin/bash
user@ubuntu:~$ sh
$ ls -l /proc/$$/exe
lrwxrwxrwx 1 adminx adminx 0 Apr  4 18:20 /proc/1255/exe -> /bin/dash

Either of the two approaches works in 99% of the cases. Of course, there are ways in which they can be subverted. For instance, symlink won't point anywhere if the executable was deleted shortly after the shell started ( and in that case you probably will encounter system issues, since removing /bin/sh, /bin/dash, or even /bin/bash is not recommended - after all a lot of scripts rely on them, especially system-level ones). Command name for shell is usually set as the very first argument in execve() syscall. This is covered in How does bash know how it is being invoked? , so if you have an application that launches a shell via execve(), it could give it any name. But these are non-standard and non-typical things, that should be avoided for the sake of consistency and security.

Getting Terminal Information

We can start with the environment variables. Many terminals seem to mask themselves as xterm-compatible, which is reported by echo $TERM or echo $COLORTERM. But then environment variables are not very reliable tool. They can be set and unset. We can do the same thing with PIDs again, except this time we will look at parent PID. As you may remember, terminal is the interface to the shell and often starts the shell itself. Therefore we can find out what process is the parent process of our shell:

$ ps -p $$ -o args,ppid
COMMAND                      PPID
bash                         1234
$ ps -p 1234 -o args
COMMAND
/usr/lib/gnome-terminal/gnome-terminal-server

Let's try with another terminal app, sakura:

$ ps -p $$ -o args,ppid
COMMAND                      PPID
/bin/bash                   16950
$ ps -p 16950 -o args
COMMAND
sakura

From there we can already see that what started this shell is gnome-terminal. This method of course works assuming you're working with interactive shell. If we're trying to find out the parent of bash -c '...' or the shell started via ssh, for example, PID may very well be from non-terminal application and maybe non-GUI at all.

So if we want to specifically deal with GUI terminal, what we can do is run xprop, click on the desired window, grep its pid, and find out what's the name of that process matching pid. Or in other words:

$ ps aux | grep $(xprop | awk -F'='  '/PID/ {print $2}')
xieerqi   2124  0.6  1.7 208068 34604 ?        Sl   18:47   1:49 gnome-terminal

Additionally, as per specifications , window managers should set WM_CLASS property. Thus, we can get that from xprop as well:

$ xprop WM_CLASS
WM_CLASS(STRING) = "sakura", "Sakura"

Of course, this also has its 1% of disadvantages: setting WM_CLASS properties relies on window manager doing that, and PID is not guaranteed for a window to be accurate ( see What process created this X11 window? ), which may involve complex debugging. And these aren't shortcomings of the methods themselves but of X11 server. However, most stable and well known window managers ( like openbox, Metacity, blackbox ) and most applications are well behaved so we shouldn't expect problems with something like Gnome Terminal or Terminator.

But when it comes to GUI terminal emulators, we don't even need to find a command. We can just use the About dialog of the window itself. Exception to that rule is xterm.


When prerm/postrm/postinst are failing, you need to remove the package with more low-level tools, as apt will stop on this error.

The first try is to use dpkg -P brscan4 and when it works install brscan4 again using apt.

If still nothing works, edit the paths like /var/lib/dpkg/info/brscan4.prerm and insert exit 0 as second line. The script will not run and not produce an error. After that, reinstalling will probably fix the errors and the re-installed script hopefully runs without problems.


I found a fix:

sudo apt autoremove gnome-software && sudo apt install gnome-software


nvidia-smi binary symlink created when you install the nvidia driver, as nvidia-340 in my case. Take a look:

darlene ➜   ls -la `which nvidia-smi`

lrwxrwxrwx 1 root root 34 Mai 24 20:52 /usr/bin/nvidia-smi -> /etc/alternatives/x86_64-linux-gnu_nvidia_smi

darlene ➜   ls -la /etc/alternatives/x86_64-linux-gnu_nvidia_smi
lrwxrwxrwx 1 root root 34 Mai 24 20:52 /etc/alternatives/x86_64-linux-gnu_nvidia_smi -> /usr/lib/nvidia-340/bin/nvidia-smi

And the final binary comes from:

darlene ➜  dpkg -S /usr/lib/nvidia-340/bin/nvidia-smi
nvidia-340: /usr/lib/nvidia-340/bin/nvidia-smi


You can mount a directory on your server with the External storage support application (built in) via SFTP. In ownCloud:

login to your admin account
go to Apps
activate External storage support
go to Admin UI
scroll down and enable the SFTP option

Now for a little bit more complicated user setup since you might want to edit the files both with your local editor and with your ownCloud text editor application. Also, this increases the security a little bit (emphasis: "a little").

I assume you have set up your Apache/nginx properly and have defined your virtual hosts as well. For now the directory is in /var/www/website.

create a system user for accessing the website's directory

sudo adduser <username> #we'll call that user 'editor' for now

set proper directory permissions

sudo chown -R www-data:editor /var/www/website

grant writing permissions to group editor for that directory and subdirectories

sudo find /var/www/website -type f -exec chmod 664 {} +; #for files
sudo find /var/www/website -type d -exec chmod 775 {} +; #for directories

If you want to know the current directory permissions:

stat -c %a /var/www/website

Sidenote: Take care about the writing permissions! 775 and 664 are not to be considered safe, you'll definitely need to know what you are doing here. The best option is not to set the permissions throughout the whole directory but set them for each subdirectory in particular.
If you do so, you should consider changing your SSH configuration to only allow SSH access via public key without password access. Also look at denyhosts, fail2ban, IPtables and all the great tools out there helping in hardening a server.

Get back to your ownCloud Admin UI and configure an external storage via SFTP:

Directory name: your choice
Type: SFTP obviously
Host: localhost
User: editor
Password: Swordfish (of course)
Root: /var/www/website
On the right: Only make that external storage available to your specific user.

Keep in mind that SFTP access is pretty slow, but at least it gets stuff done.


how to have a working compiler in an empty ubuntu without root privileges

Finally I got notice of a way to install without admin privileges make+gcc on a freshly installed ubuntu, without having to become crazy writing my own bash scripts to extract from .deb files. I just had to rely on conda!

First, install miniconda (does not require privileges)

Second, use conda to install make, gcc, ... (all available on the anaconda official channel, also!).


I changed to Ubuntu, lost my files. How do I get them back?

What you meant by lost? Whether the partition still intact? If so you can use active file recovery. If you formated the partition accidentally then you can try active partition recovery.

Sorry, I missed the point. You need it in Ubuntu right, you can install gddrescue and run ddrecue to recover the files. Please check this link for more details on ddrescue.


Custom Shortcut for switching off the display

$ xset dpms force off

Screen wakes up after moving the mouse or pressing a key.

Manually turn off monitor


How do I get a Broadcom 4306 [14e4:4324] rev 03 working?

It looks like you have determined that the open source firmware for your 4306 does not work (even though the docs indicate the 4306 is supported).  Next, try the Broadcom firmware -- accept the offer to download files when installing the b43-fwcutter package:

sudo apt-get install b43-fwcutter

The download offer is only given the first time the package is installed, so if you have already refused the download, do a purge (not just a remove) and install again.

sudo apt-get purge b43-fwcutter
sudo apt-get install b43-fwcutter

The open source firmware and Broadcom firmware get installed into different directories, and when both are present, the Broadcom version (in /lib/firmware/b43) is used.

With the firmware in place, NetworkManager may start scanning, if not, manually load the b43 driver module, or just reboot.

sudo modprobe b43

NetworkManager should start scanning and offer a list of possible connection points within a few seconds.

Select your access point, select the correct encryption method, and enter your key. If you are not broadcasting your ssid and it does not show up  in the list of access points, you might have to left click NetworkManager and select the menu item "connect to hidden network", and enter your ssid. Next boot, the connection should be automatic.


Get the Bluetooth Audio Sink working with Kubuntu 13.10 and Bose Mini Soundlink

I thing that solved my problem was to connect to headset service.  Then under pulseaudio control the audio sink was exposed. also under /etc/bluetooth/audio.conf I set:

HFP=false

and uncommented

#[A2DP]
SBCSources=1
MPEG12Sources=0

Then under pulse audio I was able to disable the sound card and switch the profile to A2DP.


How to make Diacritics be available with single key press on German keyboard layout

There are several variants of German keyboard layouts. One of them, which may be useful for you, is the German (dead acute) layout, where the ` (grave/backtick) symbol is not a "dead" key.

The file /usr/share/X11/xkb/symbols/de includes the following comment on the German (dead acute) layout:

  modify the basic German layout to have only acute as dead keys (ASCII
  grave, tilde and circumflex are needed as spacing characters in many
  programming languages and text formatters)


What if the installer says I don't have enough available hard disk space?

Alex, there is an Ubuntu wiki page on this system and about the 4Gb disc. From the link...

DellMini9
As this Laptop was originally sold with Ubuntu 8.04, Justification exists to keep this page.
Unsupported Version: This article applies to an unsupported version of Ubuntu.
Status
For installation, as of Ubuntu 11.10, (and possibly earlier) the Desktop ISO put onto liveUSB fails to load, This may have something to do with the unusual half-mini pci express ssd not being detected properly.
As some of these shipped with 4gb halfminipcie ssd storage, one may need to use the alternate-cd image for installation, as the desktop version will say there is not enough disk space, but there really is(was)
Also, everything after the 8.04 that came with your mini, you will need a wired connection to the internet to get the broadcom wifi working, as this is not included on the LiveCD.
The Ubuntu 10.04 LTS version was the last version that had innovative screen space saving features.
10.10 on have unity by default. It is possible to run Kubuntu, but one must not simply uninstall plasma-netbook, one must know some shell fu(with the livecd) to get to system settings and switch the workspace-behavior--workspace--type to desktop to be able to do anything with the livecd.
Also see: Ubuntu Intrepid Ibex (8.10) on the Dell Mini 9

...

CD Install or DVD recovery
The device doesn't come with a CD/DVD drive, so you will need to attach a USB one to the unit, and place your Ubuntu install CD in the drive. To boot from the CD ROM, press 0 during the initial boot screen (where it shows the Inspiron Logo) and choose the CD ROM drive from the drop-down menu.

So the best method would be to ...

purchase an USB dvd;
use the alternate installer.


It is telling you that an archive it downloaded (/var/cache/apt/archives/liblove-unstable0_0.10.0~pre2657ppa2_amd64.deb) is invalid, and cannot be unpacked. Since the file is in the /var/cache/... hierarchy, you can probably delete the file (sudo rm /var/cache/apt/archives/liblove-unstable0_0.10.0~pre2657ppa2_amd64.deb), and let the system download a good copy.


How to install driver for ATI Rage 128 Pro Ultra TF?

That isn't a new or different driver than the one in Ubuntu already. It is a patch to support the newer acceleration architecture in Xorg, as the older one is slated to be removed. Getting this built would require a rebuild of the package it patches, by including the patch in the packaging.

It may possibly be slightly less buggy, than the current code is, but it is also a little slower, and unlikely to fix your video stuttering issues.

It does look like the patch was committed upstream though, in July 2012, so should be included in the xserver-xorg-video-r128 package in Ubuntu 12.10 and 13.04. You may want to try a live image of one of those first, to see if the issues you're wanting to fix still occur there. If they don't, and a bug is not filed for your issues, it would be a good idea to report it, and it may be possible to get the fix released as an update to 12.04.


Can't boot Live USB Live from grub (failed to find fs)

Well, I have found a way to boot on the live USB by copying instructions related to "Try Ubuntu without installing"  as written in/boot/grub/grub.cfg, completing them with set root and boot :

set root=(hd0)
set gfxpayload=keep
linux   /casper/vmlinuz.efi  file=/cdrom/preseed/ubuntu.seed boot=casper quiet splash ---
initrd  /casper/initrd.lz
boot


Issues with importing existing source C++ code in Eclipse CDT

Install the GNU C++ compiler from the default Ubuntu repositories (g++). The build-essential package contains some additional developer tools.

Open Eclipse and select: Help -> C/C++ Development User Guide -> Getting Started -> Creating a simple application. This is a complete C++ "Hello world" tutorial including screenshots. Save the "Hello world" project when you are finished. You will need it for your next tutorial: Help -> C/C++ Development User Guide -> Getting Started -> Creating a Makefile project and the next tutorial after that: Importing your C/C++ source files into Eclipse.


How to make Adwaita Dark theme apply only to certain applications?

For GTK2 apps, the way to do this was relatively simple. You can launch a gtk2 app with a custom theme like this:

GTK2_RC_FILES=(path-to-theme) (command)

So for example, this worked:

GTK2_RC_FILES=/usr/share/themes/Redmond/gtk-2.0/gtkrc catfish

(Catfish is an app I know to be gtk2 -- you may not have it installed.)

Unfortunately, this feature broke entirely in GTK3. I can't gaurantee this will work perfectly, but you could try making simple shell scripts that configure a theme, launch the app, then unconfigure the theme. If you launch two apps at the same time, that my result in a race condition with unpredictable results.

So for example, you could launch gedit like this:

#!/bin/sh
if [ -h ~/.config/gtk-3.0 ]
  then
    rm ~/.config/gtk-3.0
fi
ln -s /usr/share/themes/HighContrast/gtk-3.0 ~/.config
gedit "$@" &
sleep 1
if [ -h ~/.config/gtk-3.0 ]
  then
    rm ~/.config/gtk-3.0
fi

Besides the race condition, doing this has some other undesirable side-effects. For one, you'll use more memory for each application that has its own theme. For another, you'll have to write custom shell scripts and launchers for each app. Finally, in my opinion, your desktop will look weird.

But there. That's how you can do it, sort of.


Is there a specific format a USB needs to be to boot from?

The solution depends on which operating system are you running now (Ubuntu, other linux, Windows MacOS). You need a tool to create a USB boot drive, and there are different tools for different operating systems.

Cloning tools are simple and reliable but it is also possible to use extracting tools, if they are well maintained (updated to work with new versions of the operating system to install).

Most modern linux iso files are hybrid iso files. Such files can be burned to a DVD disk and cloned to a mass storage device (USB stick, SSD, HDD, memory card) and the target device will become a bootable drive.

You can clone from a current Ubuntu iso file to a USB stick and use that USB stick to boot Ubuntu live and install Ubuntu into the internal drive.

dd is a cloning tool, but it is risky because it does what you tell it to do without any question. If you tell it to wipe the family pictures it will do it. A minor typing error may create chaos. You must be very careful, check and double-check that everything is correct before you press the Enter key.

Instead I recommend a tool with a final checkpoint,

in Ubuntu 16.04 LTS and newer versions: Startup Disk Creator alias usb-creator-gtk
in Ubuntu 14.04 LTS and newer versions: Disks alias gnome-disks
in Ubuntu 12.04 LTS and newer versions and other main linux distros: mkusb
in Windows: Win32 Disk Imager
in Windows: Rufus - an extracting tool and a cloning tool
in MacOS: Unetbootin - an extracting tool (not a cloning tool)


What is the difference between time and /usr/bin/time?

Let's have a look at what time actually is using the type command (see help type):

$ type -a time
time is a shell keyword
time is /usr/bin/time

So apparently, time on our system is both

a keyword directly built into your Bash shell
an executable file /usr/bin/time

Because shell keywords take precedence over executables, what you actually run when typing only time is the shell keyword. You also see that from the order in which type -a lists them, or from the output of just type time, which only lists the one effective type.

Now, let's check what each of those can do:

Executables usually have a manpage (manual page), which we can open and read using the man command, i.e. here man time.
To get help about stuff built into Bash, you have to use the help command: help time

You will note that the shell keyword supports less options than the executable, but it has other advantages, as you can e.g. time complex Bash constructs like pipelines with it. See the end of this answer for an example.

If you need to use the executable instead of the shell keyword though, you can either type the full path, i.e. /usr/bin/time, or you can prefix the command with a backslash to stop Bash from evaluating it: \time

By the way, while time is a shell keyword in Bash, it does not exist in sh (Dash), where you would only get the executable.


Can't login to VPS with newly created account via ssh

As you've written it (ssh git@ip.adres.here), ssh is trying to login to the host ip.adres.here as user git. Unless you have a git user created on your computer host ip.adres.here, you will not be able to login, and will be greeted with "Permissions denied, please try again". (NB: You WILL be asked for a password, even if that username does not exist). If this does not answer your question, please provide more details.


My computer cant read Ubuntu 12.04.3 LTS (Precise Pangolin) from CD-ROM

There is probably something wrong with your .iso file.

Here is someone with the same problem.

You can Google how to check the MD5SUM of the file using Windows, or just re-download and burn a new disc.


How can I reset auto-run settings for removable devices?

If adb devices doesn't show it, then your udev configuration needs to be corrected, and udev restarted. Perhaps then it will show up in the Removable Media area.


'LIBXML2_2.9.0' not found (run PHP-file with shell_exec)

Your library version is too old. You need libxml2 >=2.9.0

For Trusty and newer install the package libxml2

sudo apt-get install libxml2

remove the old library (backup)

mv /opt/lampp/lib/libxml2.so.2 /opt/lampp/lib/libxml2.so.2.bak

and create a symbolic link

ln -s /usr/lib/x86_64-linux-gnu/libxml2.so.2 /opt/lampp/lib


Remove all ubuntuone packages installed in your system. Otherwise, the program would be launching again in each reboot and creating the folder again.


How do I install Qt5, which comes as a .run file?

You have to make the file executable and then simply execute it.

Type the following commands in the terminal:

chmod u+x qt.run
./qt.run


What if I remove the additional graphic driver?

You could alternativly try the open source ati drivers, which would probably get installed / be used as soon as you remove the proprietary drivers (I think that happens, at least with my NVIDIA card).

You might need to set nomodeset in grub to boot or you will only get a black screen. Google "nomodeset ubuntu" or something similar to find out more 'bout it!


How can I deal with file association in different application(not in Nautilus)?

Comment out the line in .local/share/applications/mimeapps.list

inode/directory=rhythmbox.desktop;vlc.desktop;smplayer.desktop;

and insert

inode/directory=nautilus-folder-handler.desktop;


Lots of static/crackling noises after ALSA HDA DKMS installation

Crackly sound with Skype on Ubuntu

Open up “/etc/pulse/default.pa”, find “load-module module-udev-detect” and add to the end “tsched=0″, which will disable timer-based audio scheduling.  It should look like:

load-module module-udev-detect tsched=0

*NOTE: You need to have elevated privileges to alter this file you can use the built-in text editor called nano from a terminal. Use this command to open it:

sudo nano /etc/pulse/default.pa

Save (press ctrl+x then enter to save using original filename) and execute

pulseaudio -k && pulseaudio --start

to restart ALSA

I has the same issue as i m using 13.04, so mine is fixed with this fix.

I am using 13.04 so mine is load-module module-udev-detect use_ucm=0 and i have added the tsched=0 in the end and now it is load-module module-udev-detect use_ucm=0 tsched=0


How to reduce disk usage on a live usb 12.04 system?

The startup disk creator allows you to make a USB drive with any amount of space you want allocated to the home filesystem.  If you intend running Ubuntu regularly from a USB stick then burn the image to a fair sized stick and allow as much as you want to be used by Ubuntu.  If you are using it that regularly, you might want to consider a hard-drive installation?


Firefox 64.0 renders content transparent

Having the same problem, and can't find enough info about it online!

Strange "ghost images" / transparency effect in full-screen videos

For me, setting layers.acceleration.force-enabled to true in about:config fixed the issue, but I took a big hit in performance and FPS of my videos. There was visible stuttering.

In another answer in the Mozilla Support Forum, one other solution that was suggested and indeed fixed the issue was changing gfx.xrender.enabled to true, instead of forcing hardware acceleration.

I don't know which of the two is better.


SOLUTION: (from Olu Doug's comment) :

I removed the "Videos" package from Ubuntu Software Center and reinstalled it with all the recommended plug-ins. This solved the problem.


Error in Using Gparted to add Unallocated space

You are moving one partition too far, so it makes an overlap with another one. And, thats not possible. And make sure none of the partitions are mounted while processing this.


Dual Boot: Windows 8 is fine, Ubuntu is fine, but will only boot when dvd is in the disk drive

Concerning the "efi disk read error" message, I think you need to disable the Windows "Fast Startup" feature, as described here:

Can a Windows 8 partition be mounted in Ubuntu if "fast startup"is switched on?
How to Turn "Fast Startup" On or Off for a Hybrid Boot in Windows 8 and 8.1 (Windows 8 Forums)

Doing so will not fix your more important "black screen" problem, but this problem is at least as serious in the long term, since failing to address it can result in filesystem corruption and, in extreme cases, an inability to boot the computer at all.

The "black screen" problem is a known one, but there are numerous different causes and solutions. The most general solution seems to be to use the nomodeset kernel option, but there are several others, many of which are unique to particular chipsets. Searching this site reveals several questions on this topic, such as:

Black screen after GRUB, can't install. UEFI
Asus G75VX / Xubuntu 13.10 EFI installation Blank Screen
Why my live installation results blank screen?
My computer boots to a black screen, what options do I have to fix it?

I can't promise that any of these (or numerous others here or elsewhere) will help you, but I recommend you start with these answers.


How to make "Record My Desktop" capture only one monitor?

From the Record My Desktop website, you can apparently select a window to record, an area of the screen to record, or the entire desktop.  For what you are trying to do, I would set an area to record equal to the one monitor that you want to record.


Protecting WSL-Ubuntu and WSL-OpenSSH (unfiltering port 443 correctly, to use just these)

Version 1803 allows outgoing connections on all ports
Windows WSL Version 1803 (March 2018) allowed all ports as outgoing connections. Version 1809 (September 2018). However this version was pulled soon after release due to unrelated bugs. Your question doesn't mention which version you are running.
One month ago (Novemeer 2018) From Redit:
WSL support for the built-in Windows Firewall
As I understand it the October Windows 10 1809 update finally added WSL support for the built-in Windows Firewall.
Previously, the only way to use WSL was to allow all outgoing connections, as it was not aware of pico.
However, it seems the 1809 update has been pulled for unrelated issues and is and isn't available for download anymore.
I'm on 1803 and I'm wondering if there is any way to get this functionality back or do I have to wait until 1809 is re-released?
History, more info on this: https://github.com/Microsoft/WSL/issues/1852


**Wired** network disconnects when laptop unplugged

Well, I almost forgot that I asked here this question.

I have already figured out why. There is nothing to do with software, drivers, et cetra. This is indeed a hardware issue. The motherboard of my laptop will automatically turn off the wired NIC when unplugged. There is a switch in the CMOS setting named "Power save on LAN". Turning if off solves this issue.


Ubuntu upgrade fails due to missing packages. (Forbidden)

Open software & updates change download from others and select best server option after close and try to upgrade not slove your problem!

Change your server to main server

after unselect non recommends repositories

But don't unselect canonical partners and independent repositories

after press

  alt+ctrl+t
   for open your terminal and update repositories

sudo apt-get update
sudo apt-get upgrade


VM Ubuntu + drupal8 + drush = error drush en module_name -y

I tried to install a module with drush + CLI Platform:

MyName@MyName-VirtualBox: ~ / Documents / MySite/ web / sites / default $ platform drush '
Directory / app / web / modules / contrib exists, but is not writable. Please [error]
Check directory permissions.
Project colorbox (8.x-1.2) could not be downloaded to [error]
/ App / web // modules / contrib / colorbox

Yet my contrib folder is configured for reading and writing for all.

How can we verify that this is the case? ( command line ? )
And if not, how do you configure these permissions?


Your 2357:0100 device is claimed by two conflicting drivers in Ubuntu 19.04, as well several other earlier versions. The device is often helped to work better by unloading and blacklisting one driver, usually rtl8192cu, and letting the other driver, namely rtl8xxxu, do the work unimpeded.

From the terminal:

sudo -i
modprobe -r rtl8192cu
echo "blacklist rtl8192cu"  >>  /etc/modprobe.d/blacklist.conf
exit

Is your wireless working as expected now?

EDIT: Please be certain that your router is set to a fixed channel, not auto channel select. There are quite a few neighboring SSIDs on channel 11. Consider setting yours to channel 6. Also be sure you are using WPA2-AES and certainly not TKIP.

Then set your regulatory domain explicitly. Check yours:

sudo iw reg get

If you get 00, that is a one-size-maybe-fits-all setting. Find yours here: http://en.wikipedia.org/wiki/ISO_3166-1_alpha-2 Then set it temporarily:

sudo iw reg set IS

Of course, substitute your country code if not Iceland. Set it permanently:

sudo nano /etc/default/crda

Change the last line to read:

REGDOMAIN=IS

Proofread carefully, save (Ctrl+o followed by Enter) and close (Ctrl+x) the text editor.

Reboot the computer and the router and let us hear your report.


Flash does not work under different user account.

Just a couple of possibilities (not even sure they're the most likely, as not as familiar as I used to be with browser plugins):

wondering if the other users do not have access permissions to the directories the plugins are installed in - maybe the group access/world readable permissions?
maybe (variant on above's core reason) the plugins have been installed in a user-owned directory rather than a common one (in /usr/lib//plugins, usually, or nearly that)
other user's browser settings configured to look in the wrong place for plugins?

Try to figure out where the plugins are and see if the other users can see them too (and read the files).


"Extract To..." gone after updating from 16.04 to 16.10

As for as unrar, since the ubuntu/lubuntu 16.04.1 lts update, I have had to use the unrar e /home/user/downloads/filename.rar (I have been running 14.04 for a while now) have you tried updating or reinstalling PCmanfm? I think xarchiver comes default with ubuntu, is that installed on your installation, find out using apt-get, but i have never been able to open rar files w/ xarchiver


Quote from http://www.omgubuntu.co.uk/2010/11/move-google-chrome-cache-to-ramdisk/:

gksu gedit /etc/fstab

Add the following line to the bottom of the text file that opens but BE CAREFUL – do not touch, edit or enter ANYTHING else:
tmpfs  /media/ramdisk  tmpfs   defaults,noatime,mode=1777 0 0


How can i make both iptables/ip6tables run at startup?

I found this link maybe can help you

https://help.ubuntu.com/community/IptablesHowTo#Saving_iptables


If you already have ssh installed on the server and you can't connect from your home, probably you'll have to forward port 22 (or whatever port ssh is using) on the router.


How do I modify paths and change to a real path?

Copy my-udev-notify.rules to /etc/udev/rules.d and open it with gedit using gksudo, you may install gksu first:

sudo apt-get install gksu
sudo cp -iv ./stuff/my-udev-notify.rules /etc/udev/rules.d
gksudo gedit /etc/udev/rules.d/my-udev-notify.rules

Once opened, just replace in both lines /path/to/my-udev-notify/my-udev-notify.sh with your path /home/imnebuddy/Software/Other/Compressed/my-udev-notify/dfrank-my-udev-notify-0d78b20a38e8/my-udev-notify.sh. You can do it with Copy-Paste.

Save and Exit.

Now copy the cofiguration file as described in README.md and edit it. Replace /path/to/some/sound_file with the paths to the sound files in the sound directory which is located in the same directory as the stuff directory. At the end, reboot your system:

sudo cp -iv ./stuff/config_example/my-udev-notify.conf /etc/my-udev-notify.conf
gksudo gedit /etc/my-udev-notify.conf
sudo reboot


The CPU is more than powerful enough. You'll want at least 1GB RAM for Ubuntu. If you have that, then Ubuntu should be a good match. If you have less, then you might want to get Xubuntu or Lubuntu.

But in either case, when you're replacing an opeating system, I recommend that you take some time to explore alternatives. My suggestion is that you try Ubuntu, Ubuntu Gnome, Lubuntu and Xubuntu. All of them can be run from a DVD or memory stick without installing anything and all of them can do anything that Ubuntu can do, but the desktops are rather different and they have different default applications, etc.


Ubuntu and Windows Dual Boot Clock Problem

If you go to the top of the page click on the Time and it will show you the calender and where you are supposedly located, underneath that if you click on the Time and Date settings you can manually set the time from there.


According to this link,

help.ubuntu.com/community/Grub2/Setup#Configuring_GRUB_2

GRUB_DEFAULT=0 should work, if you are arriving at Ubuntu's grub menu. But there is a second step: You must make it active by running

sudo update-grub

If it is still not working, booting is not using this grub menu, but some other grub menu or other boot menu.

You may have to run

sudo grub-install /dev/sdx

where x is the drive that the computer is booting from. See this link,

help.ubuntu.com/community/Grub2/Installing#Reinstalling_GRUB_2


PDF Viewer with portable bookmarks like Foxit Reader under Windows

Head over to Foxit software, in the filed that says "Foxit reader", click "Desktop Linux", set the fields as in the following screenshot:

and click the "open with /usr/bin/software-center" and OK and follow the instructions on-screen!


Ubuntu 12 breaks gcc 4.7 build from source

As I said in my comment, the problem is not a bug in either GCC or Ubuntu, but rather an incompatible feature: multiarch. The point of multiarch is to allow binaries for multiple architectures to be installed in the same file system at the same time without collisions. This will replace the old 32-bit vs. 64-bit libraries system that used to exist, but is really more important where we want to have both Intel and ARM installed at once, for example. Presumably this isn't terribly interesting for desktop computers, but Ubuntu exists in many embedded devices (or will do) that might do this sort of thing.

Making changes like this naturally results in files being moved around, so we can expect some disruptions during the switch-over period. GCC currently does not support the new locations yet, but it will do, eventually.

Starting from a standard desktop install, these set-up steps allowed the build to work for me:

amd64 (I tested this one):

sudo -i
# apt-get install libppl0.11-dev libmpfr-dev libgmp-dev libc6-dev-i386
# cd /usr/include
# ln -s x86_64-linux-gnu/* .
# cd /usr/lib
# ln -s x86_64-linux-gnu/crt* .

I see you're using 32-bit Ubuntu. I've not tested this, but I've made the obvious changes.

ix86:

sudo -i
# apt-get install libppl0.11-dev libmpfr-dev libgmp-dev libc6-dev
# cd /usr/include
# ln -s i386-linux-gnu/* .
# cd /usr/lib
# ln -s i386-linux-gnu/crt* .

WARNING: inserting the soft links are usually harmless, for most people, but could well cause you problems further down the line. (Mostly only if you want to build both 64-bit and 32-bit projects on the same machine.)


Make "aptitude" automatically choose solution "Install" instead of "Keep"

Worked solution, is to add this parameter:

-o Aptitude::ProblemResolver::SolutionCost='100*canceled-actions,200*removals'

Found by looking at this manual. How it works - we just increase the costs of solutions which aptitude will be use:

Do not keep, if you can install or upgrade (by increasing canceled-actions counter)
Increase removals counter, because we want keep pkgs if aptitude decide to delete it


fuse: unknown option `defer_permissions'

Having looked at the sshfs man page, I'd say that defer_permissions does not exist as an option. However, default_permissions is listed.

I've used this and so far it's working for me.

Could there be a typo in the instructions you were following?  (Would it be https://www.digitalocean.com/community/tutorials/how-to-use-sshfs-to-mount-remote-file-systems-over-ssh by any chance?)

I'm sticking with the typo theory unless anyone else knows better.


is there a way to findout the keycode of a specific key in ubuntu 17.10?

Yeah, xev should do the trick. If I'm remembering right you can find it in the x11-utils package. Run xev and press the keys you want, it'll spit out a bunch of info for each event:

For just keyboard events, you should launch it in a terminal with xev -event keyboard to tell it to ignore non-keyboard events like mouse moves.


mount.nfs: access denied by server while mounting (with NFSv4)

Due to Vagrant's networking, the two VMs could not properly communicate/authenticate on different networks. I moved both VMs onto the same DHCP network (172.28.128.0/24) and the client was able to mount the share without any problems.


Re: Error (launching minecraft) Java oracle 8

Seems to be an issue with 1.8.0_31, it might be fixed in 1.8.0_60:

http://bugs.java.com/view_bug.do?bug_id=8056151

However this report might be a more exact hit and still reproduces it on 1.8.0_74 amd64:

https://github.com/LWJGL/lwjgl3/issues/149

Switching back to java 1.7 helps. Using the workaround provided at http://my.stargazer.at/2015/02/03/java-8-jvm-crash-on-linux/ mentioned by
Ruud Schmitz (thanks) helps too:

java -Dswing.systemlaf=javax.swing.plaf.nimbus.NimbusLookAndFeel -jar minecraft.jar


Where is the man page for the "rename.ul" command?

If You Don't Have Any rename.ul Manual Page

Searching the web-based Ubuntu Manpage Repository for rename.ul reveals that its manpage is in page 1 of the manual. Therefore, the name of the manpage file is rename.ul.1.gz.

Searching the package contents for that file reveals the packages that provide it:

manpages-fr-extra
util-linux

Unless you want the French manpage, util-linux is the package you want for rename.ul manpage.

It almost always works to simply search for the command itself in package contents, as the package that provides the command is virtually always the package that provides its manpage(s).

If you didn't have util-linux installed, you could install it. But this is quite an essential package, and it's unlikely you don't have it. So if you're missing the manpage, perhaps somehow that file was deleted. Then you should reinstall util-linux:

sudo apt-get --reinstall install util-linux

If You Want man rename.ul To Give You the Old Manpage in Ubuntu

None of these six versions of rename.ul's manpage in Ubuntu show a separate manpage for rename.ul, different from rename. Please note that the ul in rename.ul stands for util-linux. The rename command in Ubuntu is provided by util-linux, so any other manpage for it would probably not correctly document the command.

There are other manual pages called rename. But they are for the system and library calls, not for the rename command.

With that said, if you find a rename manpage online, you can download it and view it like an installed manpage with man -C ./filename. Please note that the ./ is necessary when specifying a manpage located in the current directory with a relative path (just like it's necessary to run a script in the current directory).


Can't install git, and any program on Ubuntu 18.04.1

try this first

sudo apt update
sudo apt dist-upgrade


Ubuntu 18.04 minimal server has two IP addresses!

I have struggled with this exact same problem and every search comes up with several others experiencing the same issue with no resolution.

FINALLY, here is what solved it for me:

ip addr flush dev <your_adapter_id>

for me it was

ip addr flush dev enp0s4

This kills the secondary IP.


DayZ doesn't run natively on Linux, only on Windows.

There is a way to run Windows applications on Linux, using Wine.  You can think of Wine like a Windows emulator, which it fundamentally isn't (Wine Is Not an Emulator).  To install Wine, install it through the Software Center or open a terminal and type sudo apt-get install wine.

To find out how well an application runs in Wine, check out WineHQ.  The entry for DayZ is here, and it appears that it's playable, but with some serious issues.  Of course, you'll have to install Steam for Windows through Wine, which is well documented here.

You may have better luck installing a more modern Wine version than Ubuntu ships with, which you can acquire by the instructions here.

The way I see it, you have three options:

Dual-boot with Windows and play DayZ on there
Try and get it running in Wine and work around the issues
Have another Windows computer in your house and use Steam In-Home Streaming

More info on the latter here.  Currently closed beta, but if you sign up you'll get an invite within a week.


How do I disable the long press Super key from showing the shortcuts window?

1) Install Compiz-Settings-Manager (sudo apt-get install compizconfig-settings-manager),

2) Go to "Ubuntu Unity Plugin" > "Experimental" and uncheck "Enable Shortcuts Hint Overlay".


Does Wubi work on Aspire One with Windows 8 pre-installed?

The Acer Aspire One netbook has been awarded the status of Certified for Ubuntu.  There should be no issue, go a head and download Wubi and install it.

I found an Aspire user who posted this.  Basically, you must do the following:

Install the 64-bit (not 32-bit!) version or else there will be errors and laggy animation.

At the login screen, you must enable the touchpad by pressing Fn+F7.  You can then enable two-button scrolling from Settings > Mouse > Touchpad.

For screen dimming and 3Dyou must install the latest AMD Catalyst driver from here.  Do NOT install the 12.10 "Stable" driver - it will break your install.

After your install, you can get rid of the AMD watermark by running this script in your terminal.

Sleep/Wake and Wifi all work out of the box.


not detecting the windows after partitioning

I'm no expert by any means but I did have some problems with dual-booting a UEFI laptop which I finally resolved.

The latest installers are able to cope with UEFI disks and secure boot so in my view trying to disable UEFI is an unnecessary complication.

I found these two articles very worthwhile the study when I was doing my dual boot and  commend them to you.

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

Allowing boot of Ubuntu on a Acer Aspire v5-531 with UEFI

I think they supersede a lot of commonly available advice because boot processes compatible with UEFI and secure boot have now been developed.

Good luck with them. If you come across more difficulties I'd be happy to try to help but with the heads-up that, as I said above, I'm no expert!


boot failure: wrong mount point (Kubuntu)

found the solution:

the problem was in fstab
because i was stressed i did look for it in the wrong place
with a kubuntu installation usb drive i was able to boot in the try-it-out version and then i could mount the drive
then wen to the "root" drive (which confusingly contais a "root" folder which is locked, but turnes out i don't need that one anyway)
in that folder is the "etc" folder in which is a "fstab.txt"
I checked with partition manager what "UUID-number" the boot-drive has, i also remembered from the error message and from mounting the external-drive (which i mentioned in my question) the UUID-number of said drive
i uncommented ("#" in front of everything) whatever was added in the last line because there was the number of the external-drive and further up was the uuid-number of the boot-drive
restarted and everything was fine

=)


How can I uninstall or disable a gnome extension in an encrypted user home directory?

if you regulary boot up to the login screen and then switch to the console Alt+Ctrl+F3 then login (be aware there is no graphical output on the password prompt).
You than can follow the answer given here How do I enable and disable GNOME extensions from the command line? by typing:
gsettings set org.gnome.shell disable-user-extensions true
This will disable all user-extensions.
Switch back to the login screen via Alt+Ctrl+F1 and login.
Now you should be able to log in again, start Extensions reenable user-extensions and disable the extension in question.


I'm posting a little recap here, that maybe can help people like me, who are a little bit confused about how to enable guest session on Ubuntu 18.04 LTS.

Ubuntu 18.04 comes with GDM as the default display manager. GDM does not have guest session support.

If you are using Ubuntu 18.04 and you need the guest session, you have to switch the display manager: form GDM to lightdm. But pay attenction, in doing this, you expose your machine with this vulnerability, that at this very day, is still open.


Ubuntu 16.04 slow boot caused by Wi-Fi adapter?

The big jump is at the sysinit script, which I believe is your old sysVinit scripts in /etc/init.d/. systemd doesn't have deeper visibility into which of these are slow, but you can systematically try disabling these and see how that affects boot time. The ones that are active are likely in/etc/rc5.d/`


If you have last updated lists, apt will download nothing. So all lines start with Hit: (or Ign:) but few or none are Get:. You should get short time.

Example, mine with 2Mbps or ~256KBps  connection.

7 sec when every thing was updated
~10 min after 1 week from last update (more time because I've source code repository active)


could not save the file /usr/... permission denied (13.04)

Please try:

gksudo gedit /usr/bin/conky-start.sh

Write the contents of the file and you should be able to save it. To make it executable, you may need to do:

sudo chmod +x /usr/bin/conky-start.sh


If you wish to adjust the setting without having to install gnome-tweak-tool & gnome-shell, ect. then in a terminal

gsettings set  org.gnome.desktop.background show-desktop-icons true

Or in dconf-editor (requires installing dconf-tools) just follow above path - org > gnome > desktop > background, enable "show-desktop-icons"


If disks support SMART, you can try smartctl (from package smartmontools).

sudo smartctl -d <ata,scsi, etc... > -H /dev/sd*

In addition to (not instead of) smartctl, or in the unlikely event that the disks do not support SMART, you can test the drive for physical/magnetic damage using the badblocks utility.


According to those command outputs, you do have a .steam directory, but it is hidden (because it starts with a .)

Use ls -d .* to show all hidden files or ls -A to show all files

The error is a directory is giving you a hint that you need to use the -r (recursive) flag to remove directories

rm -r .steam

But that is probably NOT the best way to fix your Steam issues. Try this or read this thread for better solutions.


14.04 keyboard and mouse stopped working at login screen

This post doesn't ask a clear question, but the title is exactly what happened to my machine, albeit running ubuntu 16.

I had upgraded, and while the box booted to the lightdm login screen, keyboard and mouse (laptop internal, also I tried plugging in usb) were non-responsive.  After a time the cursor in the password field stopped blinking as well.

It appears some X packages had been incorrectly deleted when i ran an apt autoremove (necessary due to a full /boot drive).

re-installing apt install xserver-xorg-input-all fixed the issue for me.

(to install this, boot into recovery mode, enable networking, and drop into the root shell.  When completed, reboot.)


Open Terminal or Alt + F2

sudo apt install ubuntu-desktop

If it doesn't work with the problem of dependency

sudo apt install -f ubuntu-desktop


"No bootable devices found" after formating SD card by $ dd if=/dev/zero of=/dev/sda bs=4MB

Ah, you've met the fabled Disk Destroyer, Eater of Data.

I'm going to assume you only have a single actual hard drive in your computer, present at /dev/sda.

When you unmounted /dev/sda (which does nothing, by the way), you were targeting your computer's hard drive. Same with the command that broke everything. Let's break it down:

sudo dd if=/dev/zero of=/dev/sda bs=4MB

In this command, you're overwriting /dev/sda (your hard drive) with /dev/zero (or no data). This is what is called a Dangerous Idea, and is why you should really triple-check your dd commands. Any data that was erased is now gone forever with zero hope of recovery.

Now, you could possibly use PhotoRec (works on non-photos, too!) to recover any files that were possibly spared from being destroyed by this command, but you will no longer be able to recover everything. If you do try photorec, use a live image, and don't touch your drive.


Just install Ubuntu Tweak and under the apps tab, you will find a link to install Google Chrome directly.

EDIT

Check images below:

Though now in your case, you will have to check the checkbox and then click install.
Hope it works out.


What are ICMP redirects and should they be blocked?

As per this article

There are certain cases where ICMP packets can be used to attack a network. Although this type of problem is not common today, there are situations where such problems do happen. This is the case with ICMP redirect, or ICMP Type 5 packet. ICMP redirects are used by routers to specify better routing paths out of one network, based on the host choice, so basically it affects the way packets are routed and destinations.
Through ICMP redirects, a host can find out which networks can be accessed from within the local network, and which are the routers to be used for each such network. The security problem comes from the fact that ICMP packets, including ICMP redirect, are extremely easy to fake and basically it would be rather easy for an attacker to forge ICMP redirect packets.
The atacker can then on basically alter your host's routing tables and diver traffic towards external hosts on a path of his/her choice; the new path is kept active by the router for 10 minutes. Due to this fact and the security risks involved in such scenario, it is still a recommended practice to disable ICMP redirect messages (ignore them) from all public interfaces.

You need to edit the file /etc/sysctl.conf
and change
###################################################################
# Additional settings - these settings can improve the network
# security of the host and prevent against some network attacks
# including spoofing attacks and man in the middle attacks through
# redirection. Some network environments, however, require that these
# settings are disabled so review and enable them as needed.
#
# Do not accept ICMP redirects (prevent MITM attacks)
#net.ipv4.conf.all.accept_redirects = 0
#net.ipv6.conf.all.accept_redirects = 0
# _or_
# Accept ICMP redirects only for gateways listed in our default
# gateway list (enabled by default)
# net.ipv4.conf.all.secure_redirects = 1
#
# Do not send ICMP redirects (we are not a router)
#net.ipv4.conf.all.send_redirects = 0

TO
###################################################################
# Additional settings - these settings can improve the network
# security of the host and prevent against some network attacks
# including spoofing attacks and man in the middle attacks through
# redirection. Some network environments, however, require that these
# settings are disabled so review and enable them as needed.
#
# Do not accept ICMP redirects (prevent MITM attacks)
net.ipv4.conf.all.accept_redirects = 0
net.ipv6.conf.all.accept_redirects = 0
# _or_
# Accept ICMP redirects only for gateways listed in our default
# gateway list (enabled by default)
# net.ipv4.conf.all.secure_redirects = 1
#
# Do not send ICMP redirects (we are not a router)
net.ipv4.conf.all.send_redirects = 0

Then apply the kernel parameter modifications above with:
$ sudo sysctl -p


The Gnome2-project is dead. So there are no packages in the offical PPAs. The best you could do is install the fork Mate or Cinnamon, where I prefere Cinnamon.

sudo add-apt-repository ppa:merlwiz79/cinnamon-ppa
sudo apt-get update
sudo apt-get install cinnamon


In alsamixer, press F4 to get to the mic settings,  and disable this "Auto-mute" thing I see on screenshot too.
And the main thing is - use pavucontrol instead of alsamixer and stop reading that 10-year-old manual you have found all this things in. Pulseaudio overrides and essentially deprecates all this stuff.


Answer edited out of the question:

@David: with your guidance and the --no-pager switch in the journalctl command, I have found the culprit(s). One stupidity, in trying to make things work I lost a / in front of the closing Directory command. Then there was a new complaint on determining the server's fully qualified server name (fixed by adding a .conf file to the conf-available directory and activate it with a2enconf). At this point I had a clean start of Apache2. The followed the Digital Ocean protocol by adding a .htaccess file to the web-root, with the command RewriteEngine on. All is now running!


Stuck in a user log-in loop on startup (fresh install)

Try this to get rid of your issue. Once you are booted up to the blank desktop... press CTRL + ALT + F1.

apt-get install --reinstall ubuntu-desktop
apt-get install unity
apt-get purge nvidia* bumblebee*
apt-get install nvidia-prime

shutdown -r now

Hope this helps!


(No output on stdout) stderr: execvp(/usr/local/nagios/libexec/check_ping) in ubuntu

If you install nagios 4 following this tutorial http://sharadchhetri.com/2014/02/08/install-and-configure-nagios-core-4-on-ubuntu-12-04-lts/", then your installation directory is /usr/local/nagios. On starting nagios and browsing to nagios admin portal, you could see the following errors
(No output on stdout) stderr: execvp(/usr/local/nagios/libexec/check_ping
(No output on stdout) stderr: execvp(/usr/local/nagios/libexec/check_users
(No output on stdout) stderr: execvp(/usr/local/nagios/libexec/check_http

This is how I fixed the above errors, Install plugins
sudo apt-get install nagios-plugins

This will install all plugins to /usr/lib/nagios/plugins directory.
Just copy all files starting with check_* to /usr/local/nagios/libexec.
cp /usr/lib/nagios/plugins/check_* /usr/local/nagios/libexec

or
sudo ln -s /usr/lib/nagios/plugins/check_* /usr/local/nagios/libexec/

and wait for nagios to reload/refresh browser window.


Laptop sort of freezes during overnight playback using VLC

1.) If your PC is still playing from NAS, you should be able to log in using ssh (if server is installed). This way you can kill vlc.

2.) Add a cron job to kill vlc in the morning. This will also show you if the vlc is the reason for the freezing screen or if some thing else is going on.


open a terminal

ctrl-alt-t

then use the menus:

edit -> preferences -> shortcuts (tab)

and change your 'accelerator'!


how can I get Ubuntu 32-bit? It seems you can no longer get it off the Ubuntu website

Use the Alternative Downloads

Scroll to Bottom, select Other Images, and your appropriate conutry.
Click a Version Number
Choose an image ending in -i386.iso

I recommend against using the most current version, but I strongly encourage choosing an LTS release.


Let Apache transform XML with XSLT 2.0 automatically

If you use the JAXP API for initiating the transformation, then you're very dependent on getting the classpath right, because the system will load whatever XSLT engine it finds first on the classpath.

If your code depends on using an XSLT 2.0 processor then this is unreliable, it's better to load Saxon explicitly rather than relying on the JAXP mechanism. To do this replace TransformerFactory.newInstance() in your code by new net.sf.saxon.TransformerFactoryImpl()


With regards to .bashrc_aliases, you need to include that file in your main .bashrc after you create it. You could add the following lines in the end of your ~/.bashrc:

if [ -f ./.bashrc_aliases ]; then
    . ./.bashrc_aliases
fi

After that, you either need to logout and back in again, for the changes to take effect, or you can run source ~/.bashrc.


The authoritative recommendation from Red Hat suggests 8GB of swap file for 8GB of RAM, which is pretty much netter than my opinion.

However, although you did not mention, if you are using Hibernation in Ubuntu, a swap partition equal to the amount of RAM is needed (op cit.).


I hear sound from microphone through built laptop speakers in 13.04. How to turn off?

Open the Terminal and type alsamixer, press the arrow keys to place under Mic and press M. Once done press Esc

Edited:

There are actually two parts in alsamixer, first is playback and other is recording.
The above only disables playback of sound from Mic, i.e. it will not mute the mic.

As recording is different, if you record a sound even with the above option, laptop will still record the sound but it will not producing those sound the speaker.

For muting the Mic, you will need to mute the mic from recording option in alsamixer.


Reverting problems caused by checkinstall with gcc build

I ended up manually removing mention of the package from the files in /var/lib/dpkg. Things continued working normally after this was done.


How do I set Ubuntu Software Center as default to apt links?

If you're using Ubuntu, you can set the default file handler for a certain file type under "Preferences > Applications" and searching for deb. Why does Firefox try to use Gedit to open .deb files may be of help.


Lock screen turn off and on : Goes to a loop asking to enter password to unlock- then turns off again.

Sometimes applications like ktorrent or certain media players have a setting to prevent the computer from going to sleep. They can sometimes even interfere with the screen lock.

Try closing these apps if running in the background, and if it works, try searching for such settings and change it to suite your needs.

For example in VLC, the setting is under-

Tools > Preferences > set options to Show All > Advanced > Inhibit the power management daemon... checkbox

Just clear it and check if it works.


You are missing install command, just do:

sudo apt install --reinstall pulseaudio


Ubuntu software center not working in Ubuntu 14.04

Try this:

sudo rm -f /var/lib/apt/lists/dl.google.com_linux_chrome_deb_dists_stable_main_*

then

sudo apt-get update

This should solve your problem


Autorunning Plex command In Ubuntu Unity on Chromebook?

For the moment, I'd suggest using upstart. To create an upstart job, create a file called startplex.conf in /etc/init/, containing:

start on startup
task
exec /usr/sbin/start_pms plex

To do this in one command:

sudo tee /etc/init/startplex.conf <<EOF
start on startup
task
exec /usr/sbin/start_pms plex
EOF


How to find directories containing two different file names?

You can do it in two steps: find directories which contain name number one, then find in the output directories which contain name number 2.

Example:

find . -name  "09* > output_first_search
cat output_first_search | grep "01*"


is there code example or api reference for “convergence”?

Head over to developer.ubuntu.com.

There you'll find how to install the Ubuntu SDK and some tutorials (like this one for instance) that contain code examples.

Good luck!


How to pass on DNS servers to another interface?

I wonder if you need to pass DNS servers for the second interface, because I'm pretty sure that there is only one system resolver. But you can check your DNS-servers with:

$ nmcli connection show <CONNECTION_NAME> | egrep "DNS|\sdomain_name_servers"

You can list your active connection name with:

$ nmcli connection show --active

You can set new DNS-servers (8.8.8.8 and 8.8.4.4 in this case) with:

$ sudo dbus-send --system --print-reply --dest=org.freedesktop.NetworkManager.dnsmasq /uk/org/thekelleys/dnsmasq uk.org.thekelleys.SetDomainServers "array:string:8.8.8.8,8.8.4.4"

And check if it is succeed with:

$ journalctl -n -b _COMM=dnsmasq

and

$ sudo kill -USR1 `cat /var/run/NetworkManager/dnsmasq.pid` && sleep .5; journalctl -n -b _COMM=dnsmasq

Update:
If you want to provide your own DHCP server which offer DNS records it's better to let your dnmasq instanse serve DNS queries. So let dnsmasq listen on your eth0 interface:

$ sudo tee <<< "interface=eth0" /etc/NetworkManager/dnsmasq.d/bind-eth0.conf
$ sudo systemctl reload NetworkManager

And set your DHCP server to offer eth0's IP address as the DNS-server.


Not able to use the latest version of Python Library Six

Don't do that! Please don't use sudo pip!
You're trying to overwrite something in the system's Python environment. If you ensist on using that environment for whatever it is you're doing, use the packages python-six and/or python3-six.
Why? Because Ubuntu depends on Python for many, many things. Replacing a system library with a new version  could mean you break vast amounts of the system. The packaged, Ubuntu-distributed versions are tested against each other.
If you want Six 1.10, you have a few options:

Upgrade to Ubuntu 16.04 which ships 1.10.
Use a virtualenv. This creates a local environment and you can have whatever versions of whatever Python packages you like. It uses the system Python binary (and that is optional) but nothing else.
Better than either one of those, do both. If you're on Python 3, you'll get access to a load of lovely 3.5 stuff (mmm async) and if you're not, then it's just a slightly later version of 2.7.


How to disable Ctrl + Tab in Ubuntu 20.04?

What you see is by default assigned to the shortcut key Ctrl+Alt+Tab. That is a shortcut key allowing keyboard access to Gnome Shell components.
First try resetting the keybinding to default:
gsettings reset org.gnome.desktop.wm.keybindings switch-panels
gsettings reset org.gnome.desktop.wm.keybindings switch-panels-backward

If that does not work, you could disable the keybindings with
gsettings set org.gnome.desktop.wm.keybindings switch-panels "['']"
gsettings set org.gnome.desktop.wm.keybindings switch-panels-backward "['']"


Use the lvcreate command along with the --snapshot option to take a snapshot.
To define the size add the --size option and to set a name add the --name option.
Select drive/partition/directory/folder where you want to store the snapshot.

Find more command line options from the Ubuntu lvcreate manual here.

And I found an excellent guide on to how use lvm snapshots for backups on tutonics


do you say that you have a motherboard that support usb 3.0 well that a well know issue that happened when the box is in suspend mode,

When the XHCI module is loaded for USB 3.0 operation the system cannot suspend. Manually unloading XHCI will allow suspend to complete normally. To avoid future suspend problems, the workaround is to add SUSPEND_MODULES="xhci-hcd" to /etc/pm/config.d/unload_module then the system can suspend normally.

P7P55D-E

* Intel LGA1156 Platform / Intel® P55 Express Chipset
* **True USB 3.0** or SATA 6Gb/s Support - Future Transfer Technology
* ASUS Hybrid Technology
* ASUS 16 Hybrid Phase Design*
  *16 Hybrid Phase = 12+2 Phase x T.Probe
* TurboV EVO - Ultimate O.C. Processor
* T.Probe - Leading Active Cooling Technology

Description of the bug and How to Fix : here


Are there any official counters which keep a track on the number of downloads of a particular Ubuntu version across different derivatives?

Ubuntu does not count how many users downloads it. Since Ubuntu does not require registrations and because there are so many non-official mirrors, there is simply no way to count how many times it is downloaded (let alone installed).

According to some assumptions there are ~20 million Ubuntu users worldwide. Mark Shuttleworth, the founder of Ubuntu, announced that Canonical's goal is to get 200 million Ubuntu users by 2015.


Will I be able to download me epub reader and use it offline to read my ebooks?

Check out FBReader for Linux @ http://fbreader.org/
I have been using it with my Toshiba and with my Acer C7.  With the C7, I flip the image so that I am holding just as a book.  It is great.


How to use grep to search for options in a man page?

Would this work in your case?
$ man ls | grep -- '--a'
     -a, --all
     -A, --almost-all
     --author

A more detailed (hopefully clearer) example of the command:
$ man shutdown | grep -- '-'
       shutdown - Halt, power-off or reboot the machine
       shutdown may be used to halt, power-off or reboot the machine.
       logged-in users before going down.
       --help
       -H, --halt
       -P, --poweroff
           Power-off the machine (the default).
       -r, --reboot
       -h
           Equivalent to --poweroff, unless --halt is specified.
       -k
           Do not halt, power-off, reboot, just write wall message.
       --no-wall
           Do not send wall message before halt, power-off, reboot.
       -c
       On success, 0 is returned, a non-zero failure code otherwise.

Edit:
As glenn jackman commented below (very useful):

And to narrow down the results to just lines starting with a hyphen:
grep '^[[:space:]]*-' –

Test run:
$ man shutdown | grep -- '-' | grep '^[[:space:]]*-'
       --help
       -H, --halt
       -P, --poweroff
       -r, --reboot
       -h
       -k

One could obviously also use apropos in Linux.
[+] External Links:
Full-text search for man pages - At Unix SE


Can't boot up ubuntu 14.04 after upgraded from 12.04

It sounds like there may be an issue with your file system. Can you boot with a LiveCD and run a file system check [1].

This should help to point you in the right direction.

Best,

Lev

[1] https://help.ubuntu.com/community/FilesystemTroubleshooting


Why does the keyboard indicator show my custom keyboard on a dark gray background?

It seems the reason was my short description was not a recognised language code. When I changed it to one (even a code for a language not listed as one of the supported languages for the keyboard layout) it became the same colour as the other layouts.

Edit: By now I've found out the indications are kept as svg files in /usr/share/icons/ubuntu-mono-[light|dark]/status/22 (I don't know the meaning of these paths) and that I can have my own short description display the way I want it to by adding an svg icon for it there. (I haven't tried it myself; just saw the information somewhere. I'm adding it here in case someone reaches this question and finds it useful.)


My suspicion (now confirmed) was that it wasn't a wallpaper, but in fact a plymouth screen. The plymouth screen is the 'splash' graphic screen that hides the boot messages.

Use the commands

sudo update-alternatives --config default.plymouth
sudo update-initramfs -u

The first command will show a list of plymouth screens installed; letting you select one. The second command re-creates initial-ramdisk to reflect change which you'll see next time.


Mouse and keyboard not working when upgraded from ubuntu 16.04 to ubuntu 17.04

I had the same problem as you after upgrading. I tried every possible solution on askubuntu, but without success. As you specified, I wasn`t able to connect to the network to download the required packages. This is mainly due to the fact that is not recommended to upgrade to a non-LTS(not Long Term Support) version of Ubuntu.
On the official website it is specified for both 17.04 and 17.10 that:

  The download of Ubuntu 17.10 is currently discouraged due to an issue
  on certain Lenovo laptops. Once fixed this download will be enabled
  again.

and also

  Mouse & Touchpad settings and behavior will not work right in the
  Ubuntu desktop if xserver-xorg-input-synaptics is installed. Some
  desktop environments such as Unity require
  xserver-xorg-input-synaptics.

It seems like the problem is caused by a BIOS incompatibility.

You can read about the known bugs and the list of effected machines here.


For some reason, you don't have an /etc/apt/sources.list file, so apt-get don't know where to get your packages from.

Create the file using sudo, then either paste this content, or use this online sources.list generator to customize it -- Choose your country and distro version, then what branches you want. I recommend only the main branches, security updates and recommended updates. Be extra careful before chosing 3rd-party or proposed pre-release updates.

After creating the file, perform apt-get update and then install your package.


Unable to download videos using youtube-dl ('sig error'), how to correct?

Had exactly the same problem.

Updated youtube-dl via:

sudo youtube-dl -U

Run youtube-dl via sudo

sudo youtube-dl
and it will inform that they have changed distribution and need to update.
Press enter and you should be good to go.


is a strong linux login password needed with full disk encryption with a strong password?

I feel the question is a bit vague but yet it has some points . The lock screen and disk encryption protects you mostly from physical (if you can call them so) attacks , meaning someone being in front of your computer literally . As you say computers can be stolen , and we all know that some data can be valuable . But I think cold boot attack is the method that hackers take data from RAM when the power is off and the encrypted disk don't offer more security . So in that sense the length of the pass doesn't really matters. As for brute force attacks 10 characters (that isn't really a word ) maybe with special characters and numbers , that covers it in the most part . Also I hear that linux kernel can be modified to keep some of the encrypted data in the CPU rather than the RAM with patches like TRESOR . If you conclude something more please share .


Secondary SSD with data files, programs not able to Read/Write from this disk

If you're using snap packages, this is a snap limitation. Snap softwares are confined to your home dir.

If you connect your software with removable-media interface, it will be allowed to access /media/* and /run/media/*.

So you can connect your software to removable-media interface and change your mount point to where it can access.  For example, /media/Data

command:
sudo snap connect libreoffice:removable-media

https://forum.snapcraft.io/t/libreoffice-snap-cant-find-my-other-hard-disk/6456


Upgrade to 14.04 and Keyboard and mouse will not load

I was having the same problem with my XPS8700 in a dual boot with Windows 8.1. What fixed it so far was disabling acpi when booting Ubuntu.

When the Grub screen appears,choose the Advanced options for Ubuntu and with the latest kernel selected press "e" on the keyboard to edit the boot options.
Navigate with the arrows down to the line that starts with LINUX and just add acpi=off to the end of that line.
Hit Ctrl + X or F10 to boot, and you should have your mouse and keyboard back.
To make this change permanent, so you don't have to do it every time, open a terminal and type:

sudo gedit /etc/default/grub

Find the line GRUB_CMDLINE_LINUX_DEFAULT and append acpi=off so that it looks like this: GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi=off"

Save and close the file, then update by running this command from the terminal:

 sudo update-grub

It worked for me, hope it helps!!!


how to stream to hdmi and Airtunes simultaneously pulseaudio

Unfortunately the RAOP protocol provided by pulseaudio-module-raop is quite limited when compared to it's Closed Source counterparts as it

can not stream to more than 1 Air Port Express
can not reconnect when the network signal was interrupted
streams with a 6 seconds delay
can not stream simultaneously to another audio sink

We have to live with that until someone provides a better solution, or the new raop2 protocol may eventually become available.

Most of all it's the rather long delay that makes simultaneous streams to other audio sinks or for watching movies rather unusuable.


(K)Ubuntu ignores my router as DNS server, fails to find local hostname

Well the tripped circuit breaker holds a clue, can give the router a factory reset, ie completely wipe its configuration, restart it and reconfigure it, or do you have a spare router to try, that might be even better.
That is suggestion number one, otherwise editing /etc/hosts is not a bad thing at all, as far back as windows 95 the hosts file was the only way to get some sanity in a large network ( more than 2 windows machines) and if you dont have too many machines to do it on it is probably worth doing, but it does sound like the routers configuration is corrupted, so try that first


Is there any way for assigning external metadata to files?

I do love Calibre. Just like it's said on the site About page "Calibre is a free and open source e-book library management application developed by users of e-books for users of e-books".