Is it okay to delete the ~/.cache folder?

To answer the question, IMO you can delete all of .cache with no long term detrimental effects.

If your .cache is growing large, it might be better to look at the contents and determine what application is making it large and re-configure a bad acting application (rather than simply deleting .cache when it grows too large).

Another directory that can take up a lot of space (and/or save an embarrassing bit of evidence) is the .thumbs directory. Many files in .thumbs seem to be duplicates.

To clean (just take care with the -rf flag and other directories ;)

rm -rf ~/.thumbs/*

When you are new to Ubuntu/Linux it is hard to know what you can and can not delete in your home directory. For the most part you can delete most anything in your home directory, programs or applications that require .cache (or other dot files such as .local) will re-create them.

Most of the time, at worst, you will lose custom configurations, but no real harm to the system.

I would not advise you start a habit of deleting things you do not understand in your home directory, back it up or use a test account. If in doubt, the safe thing would be to make a back up or move the file.

mv .cache .cache_backup

You can then restore from backup if needed.

Definitely do NOT start deleting  things you do not understand outside of your home directory.


How to backup my system so that I can create an exact replica on another computer

You should be able to use RemasterSys to do this. It is currently out of development, but is still installable.

wget -qO - http://www.remastersys.com/ubuntu/remastersys.gpg.key | sudo apt-key add -
deb http://www.remastersys.com/ubuntu [code] main

Insert either quantal or precise where [code] is. Newer code names DO NOT WORK!
After it is install, you should click Backup.


What are some interesting features of Ubuntu 16.04 LTS?

The most exciting for a long time Ubuntu Unity user is that you can
move it to the bottom.
You can also control desktop notifications for various applications.
Ubuntu Software Center has been replaced by GNOME Software.
You can use Snap packages.

Source: http://itsfoss.com/features-ubuntu-1604/


How enable GPU accelerated video encoders in FFMPEG, Ubuntu 19.04?

I've found simple solution ...

just remove ffmpeg package

sudo apt remove ffmpeg

and install SNAP package instead

sudo snap install ffmpeg

And thats it, you can use *_nvenc codecs now. They are already included in snap package. No need to download header files, no need to complile anything.

Tip: If you have ubuntu version 19.04, be sure to give the ffmpeg package all permissions (especially access to external storage) in the software center.


How To solve Eclipse menu issues in Ubuntu 13.10

(Stable way, until someone fixes the bug)

This method takes for granted that you already have your eclipse.desktop file (or that you can alternatively create a new one from scratch). Otherwise, you can momentarily take a look at the "fast way" below.

Open your eclipse.desktop file:

sudo -H gedit /usr/share/applications/eclipse.desktop

(If you can't find it in this path, try in ~/.local/share/applications/eclipse.desktop. Otherwise, you could have to find yours using locate command).
Replace the Exec= line with this:

Exec=env UBUNTU_MENUPROXY= eclipse

Where "eclipse" is the path to your eclipse executable. In this case it's just "eclipse" since there's a symlink in /usr/bin folder.

NOTE: If you can't find your eclipse.desktop file, you can simply create one from scratch in the above path, and fill it with these lines:

[Desktop Entry]
Type=Application
Name=Eclipse
Icon=eclipse
Exec=env UBUNTU_MENUPROXY= eclipse
Terminal=false
Categories=Development;IDE;Java;

Save the file.

Now you can run Eclipse from its icon as usual.

(Fast but repetitive way)

If you haven't got any eclipse.desktop file and you don't want to create it at the moment, you can simply run Eclipse with this command:

UBUNTU_MENUPROXY= eclipse

where "eclipse" is the path to your eclipse executable. Note that this is just the fast way to run Eclipse once. If you don't want to remember this command and use it every time you have to run Eclipse, follow the "stable way" above.

Or you can make an alias out of it

alias eclipse = 'UBUNTU_MENUPROXY= eclipse'

and the command eclipse will work fine.

Sources:

Keenformatics - How To show Eclipse menu in Ubuntu 13.10 Saucy Salamander (my blog)
Ubuntu documentation - EnvironmentVariables
Eclipse menus doesn't show up in Saucy


Enable GPS on BQ Aquaris E4.5 ubuntu edition without accepting the Nokia HERE terms and conditions

The GPS will work without accepting Nokia HERE but it can take time for it to get a position.
Get the app SensorsStatus and put it in GPS mode and leave the phone on. Disable the screen lock (security settings) to keep the phone active. After a while the app will show your position.

This way you can know GPS is functioning and while this worked on my BQ Aquaris 4.5, some map apps do not.


Can't connect to the internet after purging resolvconf

Download the resolvconf's DEB file using any other device and install it.

For Ubuntu 16.04,
http://kr.archive.ubuntu.com/ubuntu/pool/main/r/resolvconf/resolvconf_1.78ubuntu2_all.deb

For any other versions,

Go to https://packages.ubuntu.com/search?keywords=resolvconf
Select your version of Ubuntu
Click on all in the Download section
Click on any pool from the given list. e.g. de.archive.ubuntu.com/ubuntu.
Download the package and install it by dpkg -i <package>.deb e.g. dpkg -i resolvconf_1.79ubuntu10_all.deb.
Reboot the system sudo reboot now

Your internet should be back now.


how do I set the hung_task_timeout_secs parameter?

It is writable by root, so:
doug@s18:~$ ls -l /proc/sys/kernel/hung_task_timeout_secs
-rw-r--r-- 1 root root 0 Sep  1 07:20 /proc/sys/kernel/hung_task_timeout_secs
doug@s18:~$ cat /proc/sys/kernel/hung_task_timeout_secs
120
doug@s18:~$ echo 130 | sudo tee /proc/sys/kernel/hung_task_timeout_secs
130
doug@s18:~$ cat /proc/sys/kernel/hung_task_timeout_secs
130


Wubi doesn't start, with a "cannot mount /dev/dm-3" error

Your problem is that Wubi is not supported on software RAID arrays.

The error has nothing to do with NTFS. Wubi simply can't find the software raid volume /dev/dm-3.
Some users may get this to work on some systems, by building custom kernels, etc., but in general it's not a good idea.

Note that Wubi NEVER writes to the MBR; it simply modifies the Windows bootloader configuration.
With your software RAID, if you want to install Ubuntu without writing to the MBR, then you should do a normal Ubuntu install but towards the end, install the bootloader (GRUB) on the partition (i.e. NOT /dev/sda, but /dev/sda3 or similar).

Then you can use EasyBCD (on Windows 7) to create a bootloader entry/stub from the Windows 7 startup menu to start your Ubuntu.


Run a script at start in a terminal window (and keep it open) using startup applications (20.04)

Just run gnome-terminal -- /path/to/script.sh inside an other gnome-terminal to find whats happening. The --command option is deprecated. Also make sure your script file has the right permissions chmod u+x YourScriptFileName.sh and that your script has a shebang #!/bin/bash.


Error while trying to run Ubuntu installed on a pen-drive

In your windows download the software Rufus. Download your desired Ubuntu  iso. Then insert your pendrive and use Rufus to create the bootable usb. Have a good luck.


New mouse cursor doesn't appear in list sudo update-alternatives --config x-cursor-theme

I believe you have to move your theme to the /usr/share/icons directory for it to work.

Also you have to locate the index.theme (or any .theme file) of the theme you want to install and add it to update-alternatives using the --install option.

Let's take as example the theme ComixCursors-LH-White-Small ( a left-handed cursor theme from the package comixcursors-lefthanded ). Its index.theme file looks like

[Icon Theme]
Name = Comix Cursor LH White Small Bold
Comment = The left-handed Comix Cursors - White Small Bold
Example = default

but it should have an Inherits line equal to the directory in /usr/share/icons in which the theme is saved, otherwise it won't work. So add

Inherits = ComixCursors-LH-White-Small

Now tell update-alternatives about your new theme

sudo update-alternatives --install /usr/share/icons/default/index.theme x-cursor-theme /usr/share/icons/ComixCursors-LH-White-Small/index.theme 91

where you should change the second last parameter to the index.theme of your theme. If you did this correctly

sudo update-alternatives --config x-cursor-theme

should display your new theme, and after logging out and in, your new theme should be applied.


Ignore specific program's crashes in apport

apport has blacklist feature which I just noticed by dpkg -L apport | grep etc.

# Blacklist for apport
# If an executable path appears on any line in any file in
# /etc/apport/blacklist.d/, apport will not generate a crash report
# for it. Matches are exact only at the moment (no globbing etc.).

source: /etc/apport/blacklist.d/README.blacklist

There are already some examples in /etc/apport/blacklist.d/ like wine, firefox & thunderbird because all have their own crash handler (direct upstream report).

So just create a new file in /etc/apport/blacklist.d/.
Put the absolute path of the executable in it.


command-t vim "Could not load C extension"

Pete, you must install ruby-dev package before invoke "rake make" command.


How can I switch to Unity/Ubuntu mode from xbmc kodi?

I turn on the guest mode and then switch to default mode. However the other solution did not work.

sudo nano /etc/lightdm/lightdm.conf


At first, why you are using PuTTY in Ubuntu, when you can use terminal and ssh?

Most probably you have buggy internet connection or your server is seriously overloaded. PuTTY disconnects ssh immediately if there is short break in connection. For example OpenSSH waits until timeout.

If you can (for example using local console or similar), try seeing server load (try top) and error messages (dmesg).


Why does auth.log warn of a possible break in attempt?

The comment in the code explains it well:

/*
 * Map it back to an IP address and check that the given
 * address actually is an address of this host.  This is
 * necessary because anyone with access to a name server can
 * define arbitrary names for an IP address. Mapping from
 * name to IP address can be trusted better (but can still be
 * fooled if the intruder has access to the name server of
 * the domain).
 */

Basically as descrbed in the comments. This is significant thread if you have access based on source IP (HostBased authentication). It is less significant if you have some filtering or so.

If you don't like this error, you can always use UseDNS no in your sshd_config and this message should go away.


swapon --all --verbose : 'read swap header failed: Invalid argument'

Pretty simple fix actually. Looks like you haven't made cryptswap1 into a swap partition yet.

  mkfs.swap /dev/mapper/cryptswap1

Then you will be able to initialize it:

  swapon /dev/mapper/cryptswap1

Now finish the instructions.


www-data has access to folders in my home directory

www-data is used by apache for example.
you can easily remove the access for www-data and give back to root or any other user by using this command:

sudo chown -R root:root


NVIDIA-SMI couldn't find libnvidia-ml.so library


Which CPU do you have? If it is either an Intel or AMD (which is most likely the case) the architecture you added (ARM) is wrong. Try the following:

sudo dpkg --remove-architecture armhf

sudo nano /etc/apt/sources.list

Then replacing [arch=armhf] with deb and save the file
Lastly, run the update and install again:

sudo apt-get update && sudo apt-get install resilio-sync


NVidia 331 driver with ubuntu 13.10 - graphics crash

Since we are talking about a Mobile (integrated) video card, I would recommend checking the temperature of the video card while using it. Just leave open the nvidia-settings gui app on the temperature section:

If you see the temperature going up very fast then you have a fan/air flow or cooling system problem. I for one have had a couple of this and were solved by disasembling the laptop and cleaning the area. Normally a lot of dust or simply cloaked air flow can cause this. On other models the "smart" idea of having the cpu and gpu on the same place created the problem. I also recommend using the Nvidia PPA because they have:

Been checked for compatibility with Ubuntu
Have the latest official updates.

NOTE - Be aware of an issue you might encounter.

But as a first step, check to see if the air flow is working correctly and do a bit of cleaning on that zone, check the temp of the video card (also check the cpu) and keep the rules on how to use a laptop handy like not working on one with the bottom completely covered (like working in bed) or using graphic intensive apps and not checking the temp.


I figured it out! Here are the steps I took.

First I booted into the Live USB, because I knew I could get gcc there, and then I used "apt-get download gcc gcc-5 etc.." to grab the .deb files from the USB. Then I moved them into a folder on my Kubuntu installation. Finally, I was able to use "dpkg -i *.deb" to install all of the packages.

I wrote this answer on my, now wified, Kubuntu installation.


How do I get back the old Ubuntu settings interface?

If I'm understanding you properly you are looking for the one that was referred to as "System Settings" in the GUI which is actually unity-control-center which is still available for all supported versions of Ubuntu, although for supported versions higher than 16.04 you have to enable the universe repository in order to install it.


After 16.04.1 upgrade Samba will not start

So, finally fixed it.  Based on response at Samba does not launch after upgrading to 16.04, I had to purge all samba packages first.

So, I ran:

aptitude purge samba libnss-winbind libpam-winbind samba-dbg system-config-samaba winbind smbclient samba-testsuite samba-common-bin samba-dev samba-doc samba-dsdb-modules samba-vfs-modules

(I don't know where I picked some of those up, I think I was following someone's solution that said to install samba*)

Then I ran

aptitude install samba libnss-winbind:amd64 libpam-winbind:amd64 winbind -f

(make sure correct system architecture is used -- mine is an AMD64).

service smbd start
service nmbd start

then worked!


Juju boostrap for EC2 fails with access denied, but working credentials

Juju requires access to control an S3 bucket and EC2 instances. If your access credentials were keys generated from AWS IAM this may mean you did not add the correct access group policy to your security credentials.  The following steps may be taken to grant this access key pair to provision your AWS infrastructure:

Access the IAM control Panel

Obtain Access Key and Secret Access Key

Select User and set Policy Template

Select EC2 Full Access and S3 Full Access

Note - If you are in a corporate environment, this may voilate access policy. You should check with your Administrator if you require segmented permissions to specific AZ's or custom access levels. This can be generated by your administrator, or by following the AWS IAM Policy tutorial.


It'll be a lot of work.

In Linux, it could be done by carving out an EFI System Partition (ESP) on the disk, installing any of several EFI boot loaders on that partition, and reconfiguring the firmware to boot in EFI mode. For some firmware, you might need to convert from MBR to GPT and/or remove all traces of a BIOS boot loader, but some firmware implementations don't require this.

It gets harder in Windows, since Windows requires jumping through additional hoops to switch from BIOS-mode to EFI-mode booting. Some of those might be required by your firmware even when booting Linux, though, like the MBR-to-GPT conversion.

In sum, unless you're re-installing everything, this will involve a lot of work on a dual-boot system, with very little practical benefit. You'll also be risking total loss of all the data on your hard disk. Thus, I can't really advise this except as a learning exercise, and then only if your data aren't important.


Ubuntu Desktops 13.10 to 14.04 (Recommended)
You can easily upgrade over the network with the following procedure.

Run the update-manager application from the Unity Dash or a command line

In Update Manager, click the Settings... button, and enter your password to start the Software Sources application.

Select the sub menu Updates from the Software Sources application.

Confirm the "Notify me of a new Ubuntu version:" option is set to "For any new version", and change it if otherwise.

Close the Software Sources application and return to Update Manager.

In Update Manager, click the Check button to check for new updates.

If there are any updates to install, use the Install Updates button to install them, and press Check again after that is complete.

A message will appear informing you of the availability of the new release.

Click Upgrade.

Follow the on-screen instructions.


iptables is the low-level tool for manipulating how the kernel deals with network access, but it is rather complicated to use directly. So there are wrapper programs such as ufw:

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

which make the task of setting up firewall rules somewhat easier.

There is a GUI for ufw as well:

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

Having different rules for specific programs would be more complicated.


You can use UEFI boot/coreboot if your computer supports after first moving your installation outside a wubi container. To do this, create three new partitions on your HDD(make sure your wubi installation will fit into those partitions). I have reduced my boot time from 40 secs to 18 secs.

First step(do this on a live CD)

-Issue sudo dd if=<path-to-your-wubi-rootfs-imagefile> of=/dev/sda3 bs=512 from a Ubuntu or another Linux live cd in a terminal. Moving installation in this manner works, I had made a similar VM-to-real PC transistion. Do not copy swap partition, recreate it instead. Separate your home directory into a ext4 partition by using your favorite partition editor(GParted is available on Ubuntu Live) and a file manager(move files from your rootfs's /home directory to newly created partition-nautilus or mv <path1>/home/* <path2>/ will help in such a case). You can share Documents directory among Windows and Linux.(this unfortunately does not apply to home directories). After moving rootfs and creating the other partitions, now you can install GRUB2 by grub-install --boot-directory=<rootfs-partition-mount-point>/boot /dev/sda.

Second step(do this on your new destination)

Do a UEFI conversion according to steps described here: How can I change/convert a  Ubuntu MBR drive to a GPT, and make Ubuntu boot from EFI? Be careful about not losing ability to boot Microsoft Windows. Try disabling IPv6 after moving your installation outside WUBI. WUBI is the primary cause of slowdown here.


How can I save output of past commands in an xterm?

If you want the whole contents of the terminal history:

In the gnome-terminal menu, Edit > Select All and then Edit > Copy. (Or use your favorite keyboard shortcut for the copy.)

Then paste anywhere.


Using a bootable live cd disk image mounted on the hard drive

While I rather doubt it's possible to mount the contents of something to a partition, there is an ubuntuforums.org thread that explains how to boot ISO images with Grub2.

http://ubuntuforums.org/showthread.php?t=1549847

Basically, you edit /etc/grub.d/40_custom by copying/pasting one of the examples provided in post #1 (version name/ISO may be out of date), modify the entry according to your ISO location and partition layout, and then run update-grub .

Here is an example of the entry (for version 14.04):

menuentry 'ISO Trusty ' {
isofile=ubuntu-14.04.1-desktop-amd64.iso
loopback loop (hd0,1)/iso/$isofile
linux (loop)/casper/vmlinuz boot=casper iso-scan/filename=/iso/$isofile noprompt noeject
initrd (loop)/casper/initrd.lz
}


PHP mail() does not work on digitalocean ubuntu 16.04 server

Digitalocean has shared ip for users therefore, outlook, gmail etc. put it in the blacklist. In summary, mail() function works but does not deliver the mails.


Ubuntu 16.04 Virtualbox 5.1 Win 7 VM USB not working

In case you did not find the solution yet.
I had the same problem with Ubuntu 16.04 as host and XP as guest. None of the known solutions for the problem worked.
I found the right trail at the very end of this page :
https://bugs.launchpad.net/ubuntu/+source/virtualbox/+bug/1576768
which led me to this article :
https://phobosk.wordpress.com/2012/11/11/howto-fix-a-virtualbox-failed-to-access-the-usb-subsystem-error/

In summary, the reason is that the limit for inotify on max_user_watches is to low .

Solved by :
First, adding the following lines to  /etc/sysctl.conf

fs.inotify.max_user_instances = 256

fs.inotify.max_user_watches = 16384

fs.inotify.max_queued_events = 32768

Then restarting procps for the change to take effect with command :

sudo service procps restart

That did it !


Software Center: invalid or out of range for property 'value' of type 'gint

it seems like some files are missing, try to uninstall it and re-install it again:

Uninstall

sudo apt-get remove software-center

Re-install software center

sudo apt-get update
sudo apt-get install software-center


What are these files in my /dev directory?

These files are actually called stdin, stdout and stderr. The @ character is added by ls to tell you that they are symbolic links. ls -l would reveal that the targets of these symbolic links are /proc/self/fd/0, /proc/self/fd/1 and /proc/self/fd/2.

/proc is a virtual filesystem provided by the kernel that shows information about the operating system. Among other things, there are directories like /proc/1234 that contain information about the process with ID 1234. /proc/self is a symbolic link to the directory for whatever process is accessing it (the kernel returns a different target to different processes).

/proc/self/fd (which is also symlinked at /dev/fd) contains one entry per file that the process has open. Each entry corresponds to a file descriptor and is a symbolic link to the file (if possible — for pipes, sockets and deleted files, the symbolic link gives information that's useful for debugging but does not point to a file that you could reopen by name). These file descriptors are the same that you manipulate with C functions such as open, close, dup, read, write, etc. They are not used by the C functions, they're other ways to interact with the same objects.

The reason /dev/stdin and friends exist is that sometimes a program requires a file name, but you want to tell it to use a file that's already open (a pipe, for instance). So you can pass /dev/stdin to tell the program to read its standard input.

Further reading:

file descriptor vs. file name
file descriptors and /dev/fd
How does /dev/fd relate to /proc/self/fd/?
Understanding /dev and its subdirs and files
How to include program which only works with in/out files into a pipeline?


Django 1.8 gets installed in Python 2.7 instead of Python 3.4

You can install django with pip3, which is an easy way.

Follow below to install pip3 and django:

sudo apt-get update. Update your repositories to get the latest application versions available in your repositories.
sudo apt-get install python3-pip. This will download pip3.
sudo pip3 install django. This will download the latest global django version for python3.
django-admin --version. Verify what version you got. I got 1.8.3, which you also should get. You can also verify which version you have like this:python3

import django
print(django.get_version())

Reference

Django FAQ installation
How To Install the Django Web Framework on Ubuntu 14.04


If you plan on using already created file systems, be aware... Upon Re-installing Ubuntu 18.04

In my opinion you need not to separate /home and / partitions if you don't really need. Rest is all your wish. You can read Ish's answer.

The warning states that:

  No partition table changes and no creation of filesystems have been planned.
  If you plan on using already created file systems, be aware that existing files may prevent the successful installation of the base system.

Actually, Linux(let's say Ubuntu here) works on extended file system which is quite obvious that it is a standard. You previously had Ubuntu installed in that partition(lets say sdax). Since you already have that partition with ext4 filesystem and you are just continuing without any changes or creation of File System. It expects that you might have partition in another file system and expects you to change or create a new file system.

Like I already said that Ubuntu works on ext file system and it might expect you to change filesystem or at least format your partition(you haven't checked on Format this partition box). That's why be aware that existing files may prevent the successful installation of the base system.

So, just choose Format this partition and install Ubuntu as usual.


GNU GRUB fast boot on bios and can’t access bios now

I am unsure about your exact question as it kind of vague. It might possibly be a duplicate of this question
.
However as far as I understand,

You are unable to boot from USB or access the grub menu. Try pressing the delete button (may vary depending on the system) at the start of your boot sequence to access the BIOS menu. And move the boot order to move the windows boot priority down. [1]
Disabling fast boot: Try this blog [2] to disable fast boot from windows 10

If my understanding about your problem is wrong, please rephrase your question. [3]


juju bootstrap: "ERROR SSH authorized/public key not found"

Check to make sure that you didn't create it as root, because this way the .ssh directory will be placed in the /root directory. I made this mistake, but after copying the .ssh dir for /root to my default user directory, it worked perfectly.


Ubuntu 12.04 and Intel/AMD Radeon HD5650

I recommend checking out the Ubuntu Officially Supported graphics cards list

Your answer is there.


Snap daemon is blocking boot after upgrade to 20.04

My problem was related to the GDM3. It used the HDMI port even when no monitor was connected!!!! And in the laptop display, it kept the booting Ubunto logging.
I installed lightdm and working again: sudo apt install lightdm
What is incredible is that issues related to GDM3 are constant. I waste the full day installing Ubuntu 20.04 in my son's laptops when the Ubuntu20.04 installation does not take more than 10 minutes.


Bash script to download any new version of a file from a webpage of a particular software

I don't think Nginx provides a 'latest' link but maybe I haven't looked hard enough.

I'm afraid you'll have to perform additional steps to achieve the intended result.

You can either read the directory https://nginx.org/download/ and parse the output to determine the most current version. Then download the relevant file.

Another option is to start from here: https://nginx.org/en/download.html
and fetch the URL under the heading: Mainline version.

For either option you have to use a tool like curl or wget, parse the output, extract the URL. Or get the job done with a more sophisticated scripting language for example python + requests module and say goodbye to your sweet one-liner.

You could ask Nginx if they have permanent links for automation purposes though, you probably are not the only one doing that.


Enabling Compose key with Tweaks doesn't work on Ubuntu 18.04

You don't need to use the "US international with dead keys" layout if you're using the compose key. Simply use the standard US layout.

With the "US international with dead keys" layout, you can get some of those special characters without enabling the compose key simply by using the "level 3 select key" (level 3 select key is usually AltGr aka right-Alt key). See the layout:

For example,

AltGr+, (comma) gives "ç" and AltGr+Shift+, gives "Ç"
AltGr+A gives "á" and AltGr+Shift+A gives "Á"


error code in e:systemmd-shim post removal script process returned error exit status 2

Whenever you get a problem with the post removal script of a package you can go look at that post removal script and look what is causing it (or even bypass everything and force a package removal at your own risk, this is very useful to fix your package manager for the moment thou). This post scripts are located at:

/var/lib/dpkg/info/[the package that is causing troubles].postrm

Once there you should look at the code that is returning, in your example the console is throwing a status 2 code so you should go look for a:

... || return 2

And look why the package cannot be removed.

If you want to bypass the checker and just want the package to be removed at any cost so you can fix your package manager, look for the if statement inside the post removal script and comment all of it, the just put a return 0, save it and run one of the following commands:

sudo apt -f install
sudo apt autoremove


"FINISHME: isl_surf_choose_tiling: gen6" messages in terminal in Ubuntu 16.04

I encountered this issue when I was running matlab in the terminal. Specifically, running matlab -nodesktop -nosplash and then the plot function (or any function that uses OpenGL) gives a bunch of ../../../../src/intel/isl/isl.c:242: FINISHME: isl_surf_choose_tiling: gen6 messages.

You are seeing these messages because you are using the Oibaf PPA. There is a new patch at https://patchwork.freedesktop.org/patch/107575/ that will remove these messages, but it is not accepted yet. So, if you truly want to remove these messages, you can use ppa-purge to remove the Oibaf PPA for now by running:

sudo apt install ppa-purge  # do this if you don't have ppa-purge
sudo ppa-purge ppa:oibaf/graphics-drivers

A way to suppress these warnings is to redirect stderr to /dev/null by starting the program of interest as follows:

program-of-interest 2> /dev/null

As @Zanna points out, you can alternatively redirect stderr to a file and then grep the file for errors of interest:

program-of-interest 2> /path/to/file

In the specific case of matlab which functions as a REPL in the terminal, redirecting stderr to /dev/null causes useful warnings (e.g. syntax errors, undefined variables, etc.) to be suppressed. Redirecting stderr to a file and then grep-ping the file also somewhat defeats the purpose of using a REPL. If your program of interest isn't a REPL and is instead, say, a game, then both ways are still useful.


Using the usb cable that comes with your ups and simply connecting it to the usb port the battery icon shows up.


I have to use sudo to edit every file - no permissions to do anything

Apparently you ran something like (this is a dangerous command - do not execute!)

chown -R 700 *

making a probably non-existent user 700 owner of everything in your home directory. You may have been trying to apply the octal permissions 700 to your home directory with a command like (this is another dangerous command - do not execute!)

chmod -R 700 *

which would also be a really bad idea. Don't change permissions unless you're sure you know what you're doing. And beware the -R flag.

The reason I think you used the -R flag with chown is that hidden files were affected. But, you may have used dotglob and not used -R. If you didn't use -R originally, don't use it to revert the change.

It's possible that some files in your home directory should not be owned by you, but it's likely that they should. I suggest you chown your home directory.

If you did not use the -R (recursive) flag, then run these commands to change only the ownership of the top level files:

shopt -s dotglob            # to work on hidden files
sudo chown $USER $HOME/*
shopt -u dotglob

If you used the -R flag to change the ownership of your home directory, use this command:

sudo chown -R $USER $HOME

As an aside, as mentioned in a comment by Michael Bay, do not launch graphical applications like Gedit with sudo <application>, as this might cause root to become the owner of local config files. Use sudo's -H flag to avoid this, eg sudo -H gedit.


How to see/list history of all wiki contributions/edits by an author/user in wiki.ubuntu.com (MoinMoin?)

Ah well - here's my progress:

$ hg clone http://hg.moinmo.in/moin/2.0 moin-2.0-hg
requesting all changes
...
683 files updated, 0 files merged, 0 files removed, 0 files unresolved

$ grep -ri contributions moin-2.0-hg/
moin-2.0-hg/MoinMoin/apps/frontend/views.py:    :returns: the list of all items with user userid's contributions
moin-2.0-hg/README.txt:contributions - please see the MoinMoinAcknowledgements page there:
...

$ grep -ri contributions -B6 moin-2.0-hg/MoinMoin/apps/frontend/views.py
def _mychanges(userid):
    """
    Returns a list with all names of items which user userid has contributed to.

    :param userid: user itemid
    :type userid: unicode
    :returns: the list of all items with user userid's contributions

$ grep -ri mychanges moin-2.0-hg/
moin-2.0-hg/MoinMoin/apps/admin/templates/user/index_user.html:
{{ _("My Changes") }}

moin-2.0-hg/MoinMoin/apps/frontend/_tests/test_frontend.py:    def test_mychanges(self):
moin-2.0-hg/MoinMoin/apps/frontend/_tests/test_frontend.py:        self._test_view('frontend.mychanges', viewopts=dict(userid='000000'))
moin-2.0-hg/MoinMoin/apps/frontend/views.py:@frontend.route('/+mychanges')
moin-2.0-hg/MoinMoin/apps/frontend/views.py:def mychanges():
moin-2.0-hg/MoinMoin/apps/frontend/views.py:    my_changes = _mychanges(flaskg.user.itemid)
moin-2.0-hg/MoinMoin/apps/frontend/views.py:def _mychanges(userid):
moin-2.0-hg/docs/user/accounts.rst: **MOINTODO** +mychanges only links to the item which you edit, not the specific revision. If you edit
moin-2.0-hg/docs/user/accounts.rst: **MOINTODO** +mychanges isn't very pretty if you visit it without making any changes, it just says

So looking up +mychanges, I found thomaswaldmann / moin-2.0 / issues / #150 - /+mychanges links to items rather than specific revisions — Bitbucket:

  http://127.0.0.1:8080/+mychanges/ currently shows a list of items which the logged in user has modified (with one link to the item per edit, each on separate lines).

Right, so I give that a try on the Ubuntu wiki, while I'm logged in:

https://wiki.ubuntu.com/+mychanges/

... but no, the wiki responds: "This page does not exist yet. You can create a new empty page, or use one of the page templates." ... so I guess the Ubuntu wiki MoinMoin is older version than the latest, which apparently does feature user contribution log. Darn...


Force Ubuntu to identify LAMP php installation

The message you see is triggered by a shell function called command_not_found_handle defined in your system wide bashrc (/etc/bash.bashrc). This function is called by the bash when you enter the name of a binary which is not found in the current PATH. On Ubuntu, this uses a tool called command-not-found to search your input against a package database and suggest a package that might contain the command you entered.

Depending on how you installed your LAMP stack - by using apt-get a lot or unblobbing a big tar file - there are two answers to your question.

In case you did apt-get all the stack applications you just did not install the php-cli package. In that case you can do sudo apt-get install php7.0-cli and you are fine.

In your question you mention /opt/lamp which suggests that you did the unblob-a-tar thing. This means that you should have a php cli binary somewhere in a bin directory under your /opt/lamp. What you can do is

Call it using an absolute path, i.e. /opt/lamp/bin/php -v: this is perfect if you call it only now and then
You can add a symlink into your bin folder, i.e ln -s /opt/lamp/bin/php /usr/bin/php: helpful if the LAMP version is the only version in your system and you use it regulary
Add the path of the bin folder to your PATH environment: you might use this if the LAMP is an integral part of your system

bin/php is just an example here - your actual binary might be in a different directory under a different name. Replace it with the correct path once you found it.

If you install a full binary package in /opt it might be a good idea to check if it and if so how it uses libraries that exist in your core system. You can do this by issuing ldd /opt/lamp/bin/php and check the paths of the libs that are printed. Sometimes you get into trouble when those binaries still use your system libs but expect different versions.


The workspace switcher is disabled by default in Ubuntu 13.04, according to feature request.

Please see following bug for explanations

  This change request is now summarized in a google doc, see
  https://docs.google.com/a/canonical.com/document/d/1cbPd9WSSbFHg4Z7BSOQxDKusMe2aJjj0FEF2AMxNOZM/edit#

  ----------------------------------------- Workspace switcher should not be in the Launcher by default.

  The workspace switcher should not be in the Launcher by default (both on fresh installs and upgrades)
  Dragging and dropping the workspace switcher into the Trash should remove the icon from the Launcher and disable workspaces
  It should be possible to drag and drop the workspace icon to place it into any position in the Launcher
  If the workspace switcher is not present in the Launcher, all other workspace functions and touchpoints on the desktop should be disabled.
  These touchpoints are:

  -- The Alt+Space window accessibility menu
  -- The 'right click on window title bar' menu
  -- The workspace shortcuts listed in the SUPER key keyboard shortcuts overlay
  -- All workspace related keyboard shortcuts


node vs nodejs on Ubuntu package manager

After some more digging, follwoing information should be useful for people who may have the same confusion as I did.

I managed to find that the node package in Package repo of 14.04. It turns out that node is still Amateur Packet Radio Node Program. (It's the historical versions before renamed to ax25-node)

However, just to make things even more confusing: after sudo apt-get install nodejs or sudo apt-get install node, you can execute node -veither way.

But sudo apt-get install node gives you a totally different program (which is not nodejs).

Conclusion: sudo apt-get install nodejs installs nodejs into /usr/bin/ on Ubuntu.

PS:
The reason why after installing nodejs, you can do node -v is because in /usr/bin/, node -> nodejs*


If the filename does not contain a /, the builtin command source may look up the name in the PATH only, depending on some shell options. So instead of source .bashrc,

`source ./.bashrc`

should do what you want.

From man bash:

     .  filename [arguments]
    source filename [arguments]
           Read  and  execute  commands from filename in the current shell
           environment and return the exit status of the last command exe‐
           cuted  from  filename.   If  filename does not contain a slash,
           filenames in PATH are used to  find  the  directory  containing
           filename.   The  file  searched  for  in  PATH need not be exe‐
           cutable.  When bash is not in posix mode, the current directory
           is  searched  if  no  file is found in PATH.  If the sourcepath
           option to the shopt builtin command is turned off, the PATH  is
           not  searched.


How can I relaunch juju daemons without stop/starting local LXC containers?

A workaround might be to restart the machine, but I don't think it works at this time:

"Local provider environments do not survive reboots of the host at this time, the environment will need to be destroyed and recreated after a reboot." from

https://juju.ubuntu.com/docs/provider-configuration-local.html

See also bug: https://bugs.launchpad.net/ubuntu/+source/juju/+bug/955576


One workaround is to split the image generation and the PDF conversion. First convert the images via convert to A4@300dpi (i.e. 3508x2479), then use sam2p to convert them to PDF and then use sam2p_pdf_scale to convert them to A4.

convert -rotate "90>" -scale 3508x2479 -border 64x64 -bordercolor white in.png out.png
sam2p out.png out.pdf
sam2p_pdf_scale 595 842 out.pdf

Edit: A more complete script:

#!/bin/sh

A4_WIDTH=2479
A4_HEIGHT=3508

H_MARGIN=64
V_MARGIN=64
WIDTH=$((${A4_WIDTH} - ${H_MARGIN} * 2))
HEIGHT=$((${A4_HEIGHT} - ${V_MARGIN} * 2))

for i in "$@"; do
    TMP="/tmp/$(uuidgen).png"
    echo "$i"
    convert \
        -rotate "90>" \
        -scale "${WIDTH}x${HEIGHT}" \
        -border "${H_MARGIN}x${V_MARGIN}" -bordercolor white \
        -gravity center \
        -extent "${A4_WIDTH}x${A4_HEIGHT}" \
        -gravity center \
        -font helvetica -pointsize 80 \
        -fill white -draw \
        "push graphic-context
         translate $((${A4_WIDTH}/2 - 160)), 0
         rotate 90
         text -2,-2 '$i'
         text -2,2 '$i'
         text 2,-2 '$i'
         text 2,2 '$i'
         pop graphic-context
    " \
        -fill black -draw \
        "push graphic-context
         translate $((${A4_WIDTH}/2 - 160)), 0
         rotate 90
         text 0,0 '$i'
         pop graphic-context
    " \
        "$i" "$TMP"
    sam2p "$TMP" "${i}.pdf"
    sam2p_pdf_scale 595 842 "${i}.pdf"
done

# EOF #


Why do I get "missing os" after installing with minimal cd?

It turns out that I on a previous install had put a GPT partition table on the disk that the formatting tool did not recognize. In order to fix it I had to delete the partition table on all the harddisks using gparted before installing.


Make works fine, but the result does not run. What now?

In looking at the "Issues" or "Pull Requests" one of the pull requests labeled "small updates" has a commit that says:

Martijn Koedam        Fix building ubuntu          6d0f4a9

But in the comment section of that pull, It looks like the author decided to "Cherry Pick" only part of the commits, excluding some Distribution specific changes saying:

  Some simpleswitcher users run limited versions of make (eg, bmake)
  which the current crude Makefile supports.

This leads me to believe that it might work on Ubuntu with this commit (commit was about 4 months ago).

So try building with this fork, as it looks like they are targeting some distribution specific issues: https://github.com/DaveDavenport/simpleswitcher


How to get to a perfect jackd configuration that works trouble-free and out of the box?

I have read the Takkat comments and may be this will be ok for you:

From here,  install "pulseaudio-module-jack" then edit /etc/pulse/default.pa (sudo gedit /etc/pulse/default.pa ) :  Add the following lines, underneath the line that says #load-module module-alsa-sink
load-module module-jack-sink
load-module module-jack-source
Then create or modify  .jackrc in your home containing:
/usr/bin/jackd --no-realtime -dalsa -dhw -r44100 -p1024 -n2

Restart pulseaudio running killall pulseaudio (also  stop jackd if running  killall jackd ) :   pulseaudio will restart automatically and jackd will also start, both correctly connected so Jackd and Pulseaudio can be used at the same time .
     (this works on my Ubuntu 14.04 pc ) .

Realtime is only needed if you want  low latency for multitrack recording.
The above jackd config will produce 21ms latency which is good for most audio programs (the latency can be increases setting 2048 instead 1024 in .jackrc  , look jackd --help)
So you don't have to give realtime access to users,
(You can ignore  warnings if any ("Cannot use real-time scheduling")) .
The -dhw parameter should work on most pc, but it can be ommited  to use default audio device, or changed to -d hw:1,0 to use 2nd audio device
May be one more step if you needed to connect manually jackd to audio in/out   using "Qjackctl connect manager"  (most programs connect to jackd automatically, in this case no need to do this ) : install "jack tools"  and use "jack_connect" commands to script these connections  (you can also use aj-snapshot  to save and restore  jack connections )


I had a similar issue. My issue was that cryptsetup was not installed:

sudo apt-get install cryptsetup

Even though I could run the 'cryptsetup' command there appears to be additional stuff you need in the above mentioned package.
You can test with the following:

sudo cryptdisks_start cryptswap1

Then check /dev/mapper to see if you have the device 'cryptswap1'
Then this:

sudo cryptdisks_stop cryptswap1

The 'cryptswap1' device in /dev/mapper should now be gone.


Kernels from unplugged external hard drive showing in GRUB

Grub doesn't detect all the kernels it references on every startup; they're stored in a list that it reads when it starts.  As long as the list isn't updated, Grub will display the same kernel options.  You can run sudo update-grub with the external drive unplugged and it will remove the entries that are no longer valid.


Recovering data from a corrupted HFS+ partition

it looks like your harddisk was already (at least partly) broken with mac os x on it, then you created an "also broken" image of it. with using it further you completely killed the harddisk.

if there are usable data within the image, with a other working machine or live system (with support for reading HFS+ filesystem) you can maybe read some remaining data from the image by...

using tsk_recover (package sleuthkit) to read files on the fly from your image
mounting (mount) your image direct and look after your files
or writing it via dd to a new/other harddisk and then connect as a normal external media

if all methods don't give you some data IMHO the last thing you can try is, after mounting or writing the image to a harddisk, using photorec (testdisk) to recover them... but it is unlikely that in this case it will do the trick! :-/


Report trigger for Ubuntu Report restarts and ends with crash

Ubuntu Report (https://github.com/ubuntu/ubuntu-report) is a service that:

This tool will collect and report metrics from current hardware, partition and session information. This information can't be used to identify a single machine and is presented before being sent to the server.

It runs at every boot. Your output seems to show normal behavior.
Your output does not seem to show it "start and stop repeatedly" during a single boot cycle. If it did, that would be a bug.

Note that this tool is 100% open source. You can audit the code to see what it does. You can easily view the reports that get sent (try it: ubuntu-report show or see man ubuntu-report. There's no secret here, and there's no personal information here.


Ubuntu provides the standard Gnu Compiler Collection in the repositories.

You can install the Gnu C Compiler gcc  as well as the Gnu C++ compiler g++  with the following command:

sudo apt-get install gcc g++

You'll probably also want to install libc6-dev  (which includes the C standard library) and libstdc++6-4.5-dev  (which includes the standard C++ libraries).

If you're looking for something comparable to Microsoft's Visual C++ compiler, try taking a look at Qt - specifically Qt Creator . It's a full-fledged IDE with a visual form designer, code-editor, and debugger.

Edit:
Now that it's clear what you mean by "perfectly as in Microsoft windows?", then Qt Creator (which I mentioned above) will be perfect for your needs. You won't need to use the console to compile your applications and the Qt framework is easy to learn and use.

There's a great tutorial for getting started with Qt here.


C# + mysql + ubuntu server encoding issue

Solved:
had to add encoding usage argument, while connecting to database
Character Set=utf8


What is the most secure way to encrypt a zip file?

an encryption that has no flaw or backdoor

... does not exist.¹

GnuPG is pretty good for encryption. It's the standard tool used for various things in Ubuntu, including signing the packages you install. So if you trust the packages you install, you might as well trust GnuPG as well.

¹ I mean software for encryption, of course. One-time pads are secure.


Unmount my Windows dedicated drive on Ubuntu pendrive

Changes made in live boot systems do not persist after reboots. Also, drives other than the live USB are not mounted by default. What you have is an icon to mount the drive and open nautilus to view them. You need not worry about messing up your SSD


This is exactly what the Zeitgeist project aims to provide users with. You can download and get the latest version of Zeitgeist and the browser which will not only show you what you last worked on / downloaded but lots of other cool stuff.

Zeigeist is being worked into the unity interface for 11.04 in the places menu, so you'll only need to go there to see recent downloads sorted by date and categorised by time period.


I did some testing.
There is no problem with your ubuntu or mplayer.
The stream you mentioned just consists of silence.

if you want to doublecheck, try another stream like, for example, this one:

mplayer mms://a1075.l1062331074.c10623.g.lm.akamaistream.net/D/1075/10623/v0001/reflector:31074


Which language is ubuntu-desktop mostly coded in?

ubuntu-desktop is a meta packages that only has one purpose, which is to install a collection of packages by the Debian package system. Therefore, the package itself has no source code in this sense, but only information for the package system.

What you probably really mean is about the packages that are installed when you install ubuntu-desktop. However, this is a very broad question, since it is a collection of packages.

Some packages are written in C++ (as the main Gnome windows libraries are). Other packages use the Python gtk bindings and are hence written in Python. There are also packages that are written in mono.

I do not think, that there is a list that is kept keeping count of how many applications are written in which language. This would also be difficult to keep maintained, since the set of packages being "part of" ubuntu-desktop vary from release to release.


Touchpad/Trackpad is not found by Ubuntu 12.10 but external USB mouse works

Turns out that although I had upgraded packages, the linux kernel is in fact separate from this. By running the Update Manager I was able to resolve the issue by updating to Kernel Linux 3.5.0-27-generic and restarting.


How can I get the Nautilus file manger to open?

You can try restart nautilus

$ killall nautilus
$ nautilus -q

then try launching it again

$ nautilus

It happens to me that sometimes something - not yet understood - doesn't start properly. The above recipe fixes it.


How to know total hard disk space being used?

From the Ubuntu man page for df, try the --total option to see a grand total. Combine with -h for more readable output.

df -h --total


Editing /etc/hosts causes Apache server block to be missed

The issue is actually in the default Apache configuration file (/etc/apache2/sites-available/000-default.conf).

Uncomment the line:

#ServerName example.com and add your server's FQDN (fully qualified domain name).

Finally, run sudo service apache2 reload to have Apache pickup on the config file change.


Unable to install virtualbox additions on Ubuntu Mate

I installed make and gcc and it was able to install the guest additions.


No boot loader is installed in the MBR of /dev/sda. Is that some pain to a only Win8.1 system?

In general, you need to look at the whole context. From your Boot Repair output, you've got:

No boot loader is installed in the MBR of /dev/sda.

You also say you had Windows 8.1 installed. The vast majority of computers pre-installed with Windows 8 and 8.1 boot in EFI/UEFI mode, but this can be confirmed by:

    Boot files:        /EFI/Boot/bootx64.efi /EFI/ubuntu/MokManager.efi
                       /EFI/ubuntu/grubx64.efi /EFI/ubuntu/shimx64.efi
                       /EFI/Microsoft/Boot/bootmgfw.efi
                       /EFI/Microsoft/Boot/bootmgr.efi
                       /EFI/Microsoft/Boot/memtest.efi

...and:

/dev/sda1                   1 1,953,525,167 1,953,525,167  ee GPT

GUID Partition Table detected.

In other words, this is a GUID Partition Table (GPT) disk with Windows EFI boot loader files (EFI/Microsoft/Boot/bootmgfw.efi) on the EFI System Partition (ESP). Such computers do not normally have BIOS-mode boot loaders installed in the boot sector of the first disk, so the No boot loader is installed in the MBR of /dev/sda message is uninformative.

Two other facts are important:

You've got Ubuntu boot loaders on the ESP -- all the files under EFI/ubuntu in the Boot files: list.
Your EFI boot order is shown by the efibootmgr output, and it shows the Windows boot loader as being first in priority.

The first of those issues means that GRUB could in principle be launched in the future. If you want to completely remove Ubuntu from the computer, you must delete those files. This is likely overkill, though, and there's always a risk of a slip-up, so I don't really recommend it unless GRUB launches when you don't want it to. The second point means that GRUB shouldn't be launched by default. The computer should boot directly to Windows when you reboot.

There is one caveat, though: Boot Repair sometimes renames the Windows boot loader and puts a copy of GRUB in its place. If you've chosen the option to do this from the Boot Repair Advanced menu, the computer is likely to boot to GRUB when you reboot. If that happens, you should launch Boot Repair again, open the Advanced menu, select the option to restore boot loader backups, and run a fresh repair.

What any given function key does is very much a firmware-specific thing. Ordinarily, I'd say that the function keys should do the same thing they've always done; but I've heard of bugs that cause EFIs to start ignoring function keys for no apparent reason. (Or maybe their users have inadvertently changed an option and don't know how to undo that change.) Sometimes resetting all the firmware options or re-flashing the firmware fixes things.


13.04 PPTP VNP to Windows Server but NO Internet

The option you're looking for is "Use remote gateway for all traffic", although I'm not sure which VPN solution you're using, so I can't give you any more detail.

It's just a configuration options not a software/OS problem.  Strike that...

You appear to be referring to this bug.


How do I synchronize Thunderbird with Google Contacts

Go to http://www.zindus.com/ or https://addons.mozilla.org/en-us/thunderbird/addon/zindus/ it works at least with thunderbird 7 alpha 1 and it's the add-on I use


It looks like this card may be supported by a non-free binary driver from Broadcom, which can be installed from the broadcom-sta-dkms package.  In many cases this driver can enable AP mode, though it is not clear to me if it is supported on your specific chip.


The reason sudo apt-get install lighttpd1.5 lighttpd1.5-mod-magnet fails is as of the time of writing, that version doesn't exist. The latest version is 1.4.35 and is available here

Source: http://www.lighttpd.net/download/


Bluetooth Adapter Not Found (Samsung r580)

I solved the problem by formatting the system. Again it is 18.04 but with minimal installations, after install, I couldn't see the driver then I installed new updates and shut down my computer. Later on the driver was installed and working perfectly.


Nvidia drivers and external connections via HDMI not working when using a dual card laptop, but works with Intel card

You can use bumblebee instead of nvidia-prime for switching GPUs.

In this case DE will use Intel and HDMI will work.

You will be able to start specific applications using NVIDIA GPU with optirun command. Or add this command to .desktop shortcuts.


Your ffmpeg is really old

The FFmpeg AAC encoder is no longer considered to be experimental (it's been several years now at least), so you won't need -strict -2. You should upgrade and your original command will work. Go to johnvansickle.com, download and extract ffmpeg, and put it in ~/bin or /usr/local/bin, then log out and log in. Or follow a step-by-step guide to compile ffmpeg.

Vorbis audio in MP4?

That's certainly not common. I don't believe many non-FFmpeg based players will like that.

Otherwise, if it were AAC, which is common for the MP4 container, you could simply add the -c:a copy output option to stream copy (re-mux) instead of re-encode.

If you can't update your ancient ffmpeg

Add the -strict experimental (or the alias -strict -2) output option. Option placement matters, so make sure it is after the input and before the output:

ffmpeg -i Dwell-2019-09-19_13.23.14.mp4 -filter:v "crop=1366:556:1:212" -strict experimental Dwell_out.mp4

This is the least recommended option because you're going to miss out on thousands of bug fixes and improvements: especially to the AAC encoder.


What command is run when I select "Extract Archive Here..." in Kubuntu?

Service Menus

The 'Extract Archive Here' is a KDE Service Menu /1/

The system KDE service menu desktop files are at : /usr/share/kde4/services/ServiceMenus/

The ark_servicemenu.desktop /2/ has the 'Extract Archive Here' option. It is executing command:

ark --batch --autodestination %F

The %F /3/ is:

  A list of files. Use for apps that can open several local files at
  once. Each file is passed as a separate argument to the executable
  program.

More of the Ark options can be get from with man:

man ark

ARK(1)                                            KDE User's Manual                                            ARK(1)

NAME
       ark - KDE archiving tool

SYNOPSIS
       ark [-b] [-a] [-e] [-c] [-f suffix] [-p] [-t file] [-d] [-o directory] [KDE Generic Options]
           [Qt(TM) Generic Options]

DESCRIPTION
       Ark is a program for managing various compressed file formats within KDE. Archives can be viewed, extracted,
       created and modified with Ark. The program can handle various formats such as tar, gzip, bzip2, zip, rar (when
       the appropriate libraries or command-line programs are installed).

OPERATION MODES
       Ark can be used either as a stand-alone GUI program as well as a command-line program in order to perform some
       specific tasks.

       If invoked without the -b (--batch) or -c (--add) options, Ark is started as a normal GUI program.

       When the -b (--batch) option is used, Ark can be used to extract the contents of one or more files directly
       from the command-line, without launching its GUI.

       When the -c (--add) option is used, Ark prompts for files that should be added to a new archive or to an
       existing archive.

OPTIONS
...
   Options for batch extraction
       -b, --batch
           Use the batch interface instead of the usual dialog. This option is implied if more than one url is
           specified.

       -e, --autodestination
           The destination argument will be set to the path of the first file supplied.

Links

http://techbase.kde.org/Development/Tutorials/Creating_Konqueror_Service_Menus
http://standards.freedesktop.org/desktop-entry-spec/latest/
http://standards.freedesktop.org/desktop-entry-spec/latest/ar01s06.html


Pressing Tab for autocompleting the directory name in terminal, appens a space after the directory name and not a "/" sign

I have got the solution to my problem at this link: Tab autocomplete in terminal is not behaving properly. Now, my problem is solved. Thanks to all for giving suggestions.


No, /usr/bin/python is never supposed to point to python3. It sounds like the script in question is broken, and a bug should be reported.


I want the Grub menu to not show up, but some chages don't seem to affect anything

You need to use the GRUB holdshift script.
If you read the GRUB man carefully you woll notice that what you want is not achievable via standard settings.

Just download the script here GRUB holdshift and follow the instructions in the readme.


I can launch a Perl script with cron, but can I make it open up a window?

You can redirect the output from the cron script to a file >> /path/filename.log
Or start the script with screen: screen -Sdm perl /path/to/script.pl


My app is in pending review for long time

Since you submitted your app without packaging, you have to wait more. Because ARB have to  package and test your app. :)


I'd recommend the easily usable and amazing youtube-dl. You can get it from here.

After installing, you can get the audio in mp3 format by using the -x switch:

youtube-dl -x https://www.youtube.com/watch?v=7ty7mk3UOmo


How can I change the en_AU locale to 12 hour format?

The link Rohit provides has the answer, and it's a good one (I used it myself, and upvoted it). However, in the spirit of this, and particularly in case the link Rohit provided goes away, I'm going to write out the answer in full.

Note: this should still be considered Rohit's answer; I'm just transferring it here for posterity.

One way to do what you want would be, as Mitch says, to change your locale to one that uses the time format that you would like. However, that may entail getting other changes that you aren't interested in (Rohit's article has more on this).

More selectively, you can create a custom locale definition file with the format you want, like so:

Change directory to /usr/share/i18n/locales: cd /usr/share/i18n/locales

This directory contains locale files. The filenames are in the format <ll>_<CC> where ll is a language code (e.g. 'en' for English) and CC is a country code (e.g. US for the U.S. or AU for Australia). The idea is to customize the one you're already using (e.g. probably en_AU for the original poster - I'll use that as the example).
Copy the existing file to a new file (so that you don't lose the original settings):

sudo cp en_AU en_AU_custom

You need to use sudo because it's a root-permissions file.
Check the manual for the date command to figure out exactly what format you want for your time display:

man date

The manual says:

%r     locale's 12-hour clock time (e.g., 11:11:04 PM)

which I'll use for this example. To use a different format, just adapt the following instructions accordingly.
Convert your format text into Unicode. You can look up the Unicode equivalent for each character from a site like http://unicode-table.com/en/ , which tells us that % is <U0025> and r is <U0072>.
Edit your new file (the one you created in step 2) with your favourite editor (gedit in the example). It's still a root-permissions file, so you'll still need to use sudo:

sudo gedit en_AU_custom
Find the section marked LC_TIME and within that, the line starting with t_fmt, which indicates the time format.
Change the format to the unicode equivalent of your preferred time format, being sure to put it in quotes. For this example, the line should look something like this:

t_fmt "<U0025><U0072>"

Save the file and exit your text editor.

You now have a custom locale in the file you created (en_AU_custom in the example above).
Compile your new locale file into a system-readable locale definition with the localedef command (being sure to substitute your own filename if you used a different one from the example):

sudo localedef -f UTF-8 -i en_AU_custom en_AU.UTF-8@custom
                   ↑        ↑            ↑
                 charmap    your file    locale definition name

Now the new custom locale is available to the system.

NOTE: According to the documention of the LangpackMacros class in the macros.py file of the LanguageSelector distribution package (see /usr/lib/python3/dist-packages/LanguageSelector/macros.py in your distribution), the locale filename has a standard format:

- locale: Standard locale representation (e. g. pt_BR.UTF-8)
           Format is: ll[_CC][.UTF-8][@variant]

Thanks to Andreas Storvik Strauman for pointing this out!
Configure the system to use the new custom locale:

a) edit the file /etc/environment:

sudo gedit /etc/environment

b) add (or, if one exists, modify) the line that defines which locale to use for time/date (the file you created in step 9):

LC_TIME="en_AU.UTF-8@custom"

Save the file and exit your text editor.
Log out and back in to see your new format being applied.

Note: You can use the same process to modify the date/time format (d_t_fmt), date format (d_fmt), am/pm format (am_pm), standard 12 hour notation (t_fmt_ampm), and many other locale settings.


System not booting due to upgrade failure from 16.04 to 18.04?

Interrupting a release-upgrade is among the most damaging things you can do to your system.

For users with the proper skill, this is sometimes recoverable and sometimes not - it depends upon exactly which packages were being istalled at the moment of interruption.

Most users who suffer from an interrupted release-upgrade find that a clean install is the fastest and easiest way to return to a functioning Ubuntu system.

Use a LiveUSB to preserve your data on to some other media.

Then use the LiveUSB to reinstall Ubuntu.


Error editing connection Unable to find a connection with UUID ('null')

Search Ubuntu: Enter "Network connection" -> Add > Ethernet -> set Automantic(DHCP) at Ipv4 and tick "require ipv4 addressing for..." -> Save.


LinkSys AC1200 Wireless-AC USB adapter install

This can be done on a command line terminal:

  This is a brand new device which needs a separate driver. Install it
  via LAN connection:

sudo apt-get install linux-headers-$(uname -r) linux-headers-generic build-essential git
git clone https://github.com/abperiasamy/rtl8812AU_8821AU_linux
cd rtl8812AU_8821AU_linux
make
sudo make install

  Load the driver and check:

modinfo 8812au | egrep -i 'versi|filen|003f'
sudo modprobe -v 8812au
iwconfig
iwlist chan

  Do not remove the driver folder. After a kernel update you need to
  compile again:

cd rtl8812AU_8821AU_linux
make clean
git fetch
git reset --hard origin/master
make
sudo make install

Be aware, that git fetch requires internet access to fetch driver updates from its source code repository, so you may want to do that before booting the new kernel.

(Source with some modifications)


Is it possible to record/screenshare on a kvm (with qemu) virtual machine to a host without a capture card

yes you can share the guest with any swoftware that can share/record windows or sections on your screen.
I've used recordmydesktop to capture videos of guests as well as sharing them via google meet.
I can't tell you how to do things in discord, but from a qemu/kvm perspective just use virt-manager or virt-viewer to view your guest which will give you a window which inside holds what the guest thinks is the full screen.
Then use your screen sharing/recording software to share that window or that area of your overall desktop.


WUBI installed Ubuntu not showing up at boot menu after Windows reinstallation

Copy root.disk file (this contains all your Ubuntu data) from your Ubuntu installation drive using live USB or anything.
Re-install Ubuntu into the same partition (drive) with WUBI.
Once installation is complete, copy/move back the root.disk file from the backup you made.

This should solve your issue.


Ubuntu detecting two external monitors as only one?

Did you first try without the docking station to make sure this is even possible with your hardware (1 primary display + 2 external - I suspect maybe some docking stations only support 1 external display?)?

Does it work in Windows (if you can test that)? If it works without the docking station or in Windows, then you can easier narrow down the problem (conclude that the problem is not software-related)? It's always a good approach to systematically try things out, to narrow down the problem (explain what you've tried and why).


I have the same problem on my mac with Radeon X1600 card. My screen is connected via DVI cable and when I use keyboard to switch apps or use search option both screens act strange. For now my only solution is to use mirror screen option or only one screen. It is graphic driver problem.


Error installing Gerix Wifi Cracker Xubuntu 14.04

Open a terminal
Download your deb again. eg:

cd
wget http://www.clshack.it/nopaste/gerix-wifi-cracker-ng-2.0-bt7.deb

Download the package

sudo apt-get install dpkg-dev

Create a temporary folder

mkdir ~/deb$$

Make a copy of the deb file

cp gerix-wifi-cracker-ng-2.0-bt7.deb ~/deb$$

And use this commands:

cd ~/deb$$
dpkg-deb -x gerix-wifi-cracker-ng-2.0-bt7.deb deb
cd deb
dpkg-deb -e ../gerix-wifi-cracker-ng-2.0-bt7.deb

Create the file

nano ../svn.sh

Add this code

#!/bin/bash
# SVN Emergency Fix
function rdirls() {
    for i in $1/*
    do
        if [ -d "$i" ]
        then
          echo $i
          rm -rf $i/.svn
          rdirls $i
        else
          echo "NOT " > /dev/null 2>&1
        fi
    done
}
if [ -d "$1" ]
then
  echo $1
  rm -rf ./.svn
rdirls $1
fi

Save and close
Use this commands

chmod a+x ../svn.sh
../svn.sh .
cd ..
sudo dpkg-deb -b deb
sudo dpkg -i deb.deb

Source


How to repair a failed program install on Ubuntu?

Open a terminal by hitting Ctrl+Alt+T, and type the following:

sudo dpkg --configure -a

(Enter your password when prompted.)

This will start configuring packages (applications) that were about to be installed (unpacked) but not configured. Once this is finished, open up the Ubuntu Software Center and try to install the program again (if it's not already installed).

If the above does not fix your problem, type the following in the terminal:

sudo apt-get -f install

This will attempt to download and install packages that are needed to run programs.


Inconsistent audio over HDMI on Ubuntu 18.04 (possible codec issue?)

EXACTLY Same here, the case would be worse if I use my usb-c hub to connect HDMI cable (ThinkPad E580 - Ubuntu 18.04)

It seems the problem is not the Files, But randomly the player changes the output profile!

You can Install pavucontrol  and in Playback Tab make sure that the player uses appropriate output profile (in your case HDMI output).


Suspend temporarily linux update apt for the session until reboot

You can run a command based on this answer:

How to disable apt-daily.service on Ubuntu cloud VM image?

Create a script:

#!/bin/bash

systemctl stop apt-daily.service
systemctl kill --kill-who=all apt-daily.service

# wait until `apt-get updated` has been killed
while ! (systemctl list-units --all apt-daily.service | egrep -q '(dead|failed)')
do
  sleep 1;
done

# now proceed
echo Apt Daily Service has been killed

Mark the script as executable in order to call the command:

sudo chmod /path/to/my_script.sh

You need sudo powers to call the command:

sudo /path/to/my_script.sh

When you are away from the hotspot and back to your regular network reboot to reinstate apt services or type:

sudo systemctl start apt-daily.service

Of course you can forgo the fancy script altogether and stop services with:

sudo systemctl stop apt-daily.service


How to set a static IPv6 address for an LXD container

From Stéphane Graber, the project leader of LXC/LXD, I've got the following answer to my issue:

  Static IPv6 assignment can only work in stateful DHCP mode as otherwise SLAAC is used to assign the address.

  You can enable stateful DHCP with:

lxc network set lxdbr0 ipv6.dhcp.stateful true

  But note that no Linux distribution does DHCPv6 by default, so you'll also need to update your container's /etc/network/interfaces (or similar based on distribution) to actually do DHCPv6.

This was the missing part I could not find in any documentation. It also means that it is not possible to change IPv6 addresses from outside the container the same simple way it can be done with IPv4.

In my case I had to add the following line to /etc/network/interfaces.d/50-cloud-init.cfg inside the container.

iface eth0 inet6 dhcp

Without comments it must look something like this:

auto lo
iface lo inet loopback

auto eth0
iface eth0 inet dhcp
iface eth0 inet6 dhcp

The file is called from /etc/network/interfaces. It might be different on other distributions.

Finally it should work after a restart of the container (at least it worked for me).

I hope this helps others as well.


"libpeas-WARNING **: Could not find loader 'python3' for plugin" when loading a pluging in gedit

I had the same issue with Ubuntu 12.04 and Gedit 3.4.1, but with a different plug-in.

This is how I resolved it: Find the file [plugin-name]*.plugin in gedit's plugin directory and edit the line Loader=python3  to Loader=python

My gedit plugin-dir was under /usr/lib/gedit/plugins/ if it helps.


Is there a way to connect to a local pc via a gateway without having the gateway shine through?

I can think of two possible solutions. Each involves running nautilus on the remote computers instead of your home computer.

First. If your gateway box can run nautilus remotely, use something like:

ssh -X gateway.company.com nautilus

This would start nautilus in the gateway (assuming it is installed) and display it on your home computer. Then you may be able to browse other computers in the LAN using sftp if you know their local host names or IP addresses.

Second. If the gateway does not have nautilus installed or for some reason sftp from within nautilus does not work when running on the gateway, you can try to run nautilus on one of the destination machines like this:

ssh -t -X gateway.company.com ssh -X computer.with.files.to.browse.local nautilus

This would open nautilus in the final remote destination "computer.with.files.to.browse.local" and display it on your home computer via the gateway.

See details at: https://serverfault.com/questions/149846/access-remote-server-with-nautilus-through-double-ssh-tunnel

Hope this helps.


Solved, I just had to run this:

xrandr --output HDMI1 --auto --right-of eDP1


How to restore boot from HDD when boot-repair fails?

There is a problem with your partition table: it indicates an initial partition size of 596.18 GB while your HDD seems to have a size of 320.1 GB. Hence why it complains with a message like "Partition outside the disk detected".

Repairing can't really help as the tool can't guess what your partition table should look like.

Reformatting will solve your problem, after which you can proceed with the reinstallation of your operating systems (good tip: install Windows first, then Linux).

You will physically lose all data on your hard disk though (even if it looks like there isn't much to lose anymore).


Add thousand separator to gnome calculator in Ubuntu 18.04

I had trouble finding this too. Have a look at the Calculator dropdown item next to Activities. You'll find the Preferences menu there.


When I encrypt my home directory in Ubuntu, how does it affect programs trying to access my home directory?

After you have encrypted your home directory using the ecryptfs-migrate-home command, your home directory is always encrypted, irrespective of what various programs you are actively using.

You can see the encrypted files in /home/.ecryptfs/matthew/.Private. What you see in /home/matthew directory is actually the decrypted version of files present in /home/.ecryptfs/matthew/.Private. Note that files present in /home/matthew are not saved anywhere, they are just decrypted on-the-fly.

For example, when you try to access /home/matthew/myfile.txt, ecryptfs will look for the encrypted version of this file in /home/.ecryptfs/matthew/.Private, decrypt it and display the decrypted version as /home/matthew/myfile.txt.

Similarly, when you write to the file /home/matthew/myfile.txt, ecryptfs will encrypt the content and save it inside /home/.ecryptfs/matthew/.Private instead.

This is actually completely seamless and transparent to the user. You can access your home directory just like you used to before encryption.

Your files are inaccessible until you login (/home/matthew directory is (almost) empty (some files are present to make the encryption work).). However, do note that once you login, /home/matthew will be mounted to show the decrypted version of /home/.ecryptfs/matthew/.Private and any running programs will be able to access files available in your home directory.

I hope this clears your doubts.

P.S. Record and make a note of the key that ecryptfs provides after the setup procedure. In case anything bad happens (e.g., operating system crashes), without this key your files will be inaccessible.


How can I disable the prompt to run programs for my digital audio player's memory card?

Right now, there is nothing you can do. Nautilus doesn't have the functionality to recognize that there are two storage devices in one player.

As a workaround you can go to the nautilus settings and edit them so that no prompt at all is displayed. You still have the option to open the default media player by right-clicking on the device-icon.


Responding to command prompts automatically without extra packages

Using a loop might be helpful.

while true; do echo yes; done | command

With arrays:

declare -a arr=("yes" "no" "no"); for i in "${arr[@]}"; do echo $i; done | command

Or as @steeldriver suggested:

printf '%s\n' yes yes no | command

Lets say command is a script asking for inputs:

for i in {1..3}
do
    read -p 'Yes or no' c
    echo $c
done

The output would be: 3 yes in first case and yes, yes, no in the second one.


Terminating the Terminal process for a particular outcome

a bash shell knows its parent process, so you could do:

(( number == 2 )) && kill $PPID

ref: http://www.gnu.org/software/bash/manual/bashref.html#Bash-Variables


after troubleshooting for many hours i was able to find two attributes to add to my current SSSD.conf allowing pam_sss & pam_unix to respond to sss & active directory. fixing AD desktop gui logins. ad_enable_gc = False & ad_gpo_access_control = permissive
[sssd]
services = nss, pam
config_file_version = 2
domains = Webdomain.ORG

[domain/Webdomain.ORG]
ad_enable_gc = False
ad_gpo_map_interactive = +unity
ad_gpo_access_control = permissive


run problem in packettracer6.2 ubuntu 16.04

At first check your system integrity and install all upgrades:

sudo apt-get check
sudo apt-get update
sudo apt-get dist-upgrade
sudo apt-get install -f

Let's assume that you have extracted your CPT distribution to ~/Downloads/PacketTracer62. So cd ~/Downloads/PacketTracer62

Then run sudo ./install.

By default it will install to /opt/cpt, it runs apt-get by installer and then create symlink in /usr/local/bin.

During installation I got error messages about lib32bz2-1.0 package, but after installation I can launch packettracer on my 64-bit Ubuntu 16.04 LTS.

It seems that apt-get part failed on your machine. You can try to reinstall CPT with sudo ./install again. Or install all needed packages by hand:

sudo apt-get install lib32z1 lib32ncurses5 lib32tinfo5 gcc-6-base:i386 libc6:i386 libgcc1:i386 gcc-5-base:i386 libstdc++6:i386 \
libc6-dev:i386 libssl-dev:i386 libssl1.0.0:i386 linux-libc-dev:i386 zlib1g:i386 zlib1g-dev:i386 \
gstreamer1.0-plugins-base:i386 libaudio2:i386 libavahi-client3:i386 libavahi-common-data:i386 libavahi-common3:i386 libbsd0:i386 \
libcap2:i386 libcdparanoia0:i386 libcomerr2:i386 libcups2:i386 libdbus-1-3:i386 libdrm-amdgpu1:i386 libdrm-intel1:i386 \
libdrm-nouveau2:i386 libdrm-radeon1:i386 libdrm2:i386 libedit2:i386 libelf1:i386 libexpat1:i386 libffi6:i386 libfontconfig1:i386 \
libfreetype6:i386 libgcrypt20:i386 libgl1-mesa-dri:i386 libgl1-mesa-glx:i386 libglapi-mesa:i386 libglib2.0-0:i386 libgmp10:i386 \
libgnutls30:i386 libgpg-error0:i386 libgssapi-krb5-2:i386 libgstreamer-plugins-base1.0-0:i386 libgstreamer1.0-0:i386 libhogweed4:i386 \
libice6:i386 libicu55:i386 libidn11:i386 libjbig0:i386 libjpeg-turbo8:i386 libjpeg8:i386 libk5crypto3:i386 libkeyutils1:i386 \
libkrb5-3:i386 libkrb5support0:i386 liblcms2-2:i386 libllvm5.0:i386 liblzma5:i386 libmng2:i386 libmysqlclient20:i386 libnettle6:i386 \
libogg0:i386 libopus0:i386 liborc-0.4-0:i386 libp11-kit0:i386 libpciaccess0:i386 libpcre3:i386 libpng12-0:i386 libqt4-dbus:i386 \
libqt4-declarative:i386 libqt4-network:i386 libqt4-opengl:i386 libqt4-script:i386 libqt4-sql:i386 libqt4-sql-mysql:i386 libqt4-xml:i386 \
libqt4-xmlpatterns:i386 libqtcore4:i386 libqtdbus4:i386 libqtgui4:i386 libqtwebkit4:i386 libselinux1:i386 libsensors4:i386 libsm6:i386 \
libsqlite3-0:i386 libsystemd0:i386 libtasn1-6:i386 libtheora0:i386 libtiff5:i386 libtinfo5:i386 libtxc-dxtn-s2tc0:i386 libuuid1:i386 \
libvisual-0.4-0:i386 libvorbis0a:i386 libvorbisenc2:i386 libx11-6:i386 libx11-xcb1:i386 libxau6:i386 libxcb-dri2-0:i386 libxcb-dri3-0:i386 \
libxcb-glx0:i386 libxcb-present0:i386 libxcb-sync1:i386 libxcb1:i386 libxdamage1:i386 libxdmcp6:i386 libxext6:i386 libxfixes3:i386 \
libxi6:i386 libxml2:i386 libxrender1:i386 libxshmfence1:i386 libxslt1.1:i386 libxt6:i386 libxxf86vm1:i386 mysql-common qt-at-spi:i386 libqt4-scripttools:i386

And for sure install missed lib32bz2-1.0 package from Trusty

wget http://mirrors.kernel.org/ubuntu/pool/main/b/bzip2/lib32bz2-1.0_1.0.6-5_amd64.deb
sudo apt-get install ./lib32bz2-1.0_1.0.6-5_amd64.deb

and rerun CPT installation (confirming overwrites):

sudo ./install


Your video card based on the Intel chips.
I suggest you refer to Bumblebee project support:

Ubuntu Wiki: Bumblebee
Bumblebee project page: Installing Bumblebee 3.0


I would first check if the wired network is actually working correctly. Do you know if other people or machines are actually able to connect using a wired connection on the same network.

Second, I would check if the network adapter is functioning correctly. Is the same network adapter able to connect successfully on another network?

Thirdly, check if you are able to get an IP address via DHCP on the network. You can do this by running ifconfig from a terminal.

You may also need to confirm whether network policies are in place that may be limiting your ability to connect on the wired network.


Ubuntu 14.04 from 13.10 (Using ISO) - What about Existing Applications working in 13.10

Shouldn't affect your current environment to upgrade from the CD -- just choose the upgrade option in the installation type menu.

On the other hand, sudo apt-get dist-upgrade will accomplish your purpose, but a good network connection is recommended.

-F


Where are these missing options in menuconfig?

These options depend on what version of kernel you are using and what dependencies
need to be turned on to become available these are described here:

DMAR
DMAR_DEFAULT_ON
PCI_STUB


Creating a Legal Notice upon login in xubuntu 12.10

You would first need to create some method to show the notice. The most straightforward way to do this would be to create a simple html page and display it to the user using firefox file:///home/user/legal_notice.html (from a terminal).

If that works you can proceed to add it as a 'Startup application' using the following method: http://xubuntugeek.blogspot.nl/2011/12/add-application-to-xfcexubuntu-session.html

Furthermore you need to be absolutely sure that your legal notice does not conflict with Ubuntu's software licenses (such as, but not limited to GPLv2).


I solved the above problem by installing pip by the following command
python -m pip install -U pip

Now pip is working fine..


I have several python versions installed and I want to remove the packages installed under them

Do not - ever - remove a python version if you did not install it yourself. Ubuntu has tons of scripts running in python - therefore it needs a defined python environment. There are a lot of "I've removed python now I have a problem" questions in this forum - due to a removal of the "official" python environment.
You always can install additional versions via pip and remove them. And you can set those as default version
Edit
Just of today python V3.8.5 is the current "offical" version of Ubuntu 20.04


Steam doesn't start with nvidia drivers in Ubuntu 16.04. No error shown

Try going to http://steampowered.com and downloading a more recent version of steam directly from them. You'll end up with a .deb file; if you double click it in the file manager it should open up in the "Software" program. It will allow you to install from there and should download all the dependencies that steam requires.


Built-in monitor not working anymore after security and hardware update

I think I'm going crazy here...

The situation fixed itself after the laptop went into standby over lunch. When coming back from standby the display configuration had completely changed (the displays were now mirrored, something I had previously tried but with just as little effect as everything else), and the image was on both screens. I could then reset the configuration, and it works. This wouldn't be half as baffling if half a dozen reboots since the problem started would have shown any effect.

I have no idea what happened, but hey, it's working again.


Where is the update to 14.04.1 in update-manager?

Upgrading to a point release is not like upgrading to a new full release.

Just do:

sudo apt-get update
sudo apt-get upgrade (dist-upgrade as needed)

and you will have the point release installed.

You can confirm your version with:

cat /etc/lsb-release

DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=14.04
DISTRIB_CODENAME=trusty
DISTRIB_DESCRIPTION="Ubuntu 14.04.1 LTS"


The git repo you've created isn't a bare repository. A bare repository is a repo without the working tree.

From git-scm

  Now, you can set up an empty repository for them by running git init
  with the --bare option, which initializes the repository without a
  working directory:

You can create a bare repo with:

`git init --bare <project name>`

Transforming a normal repo into a bare repo is not that hard, you can your best answer on StackOverflow


If the hardware is properly installed next step is to tell GIMP about this input device. I have Lenovo ThinkPad X230 Tablet with Ubuntu 16.04 and I have not installed any other additional drivers. I've just tested the instructions from this video on my tablet and now the pen works with presure. The steps are:

1. Open GIMP and go to Edit→Preferences→Input Devices→Configure Extended Input Devices...

2. On the left side into the opened window will be displayed a list with the alternative input devices. Find and select your device.

3. Then on the right side click on the drop-down mode menu and select screen or window. Then click on save and close the preferences window.

4. Now you can use this device. You can setup its behaviour by the GIMP's feature Paint dynamics.

I've looked at several photos of Samsung Notebook 9 Pro and I think this pen device isn't passive.

In my opinion it is active and it uses so called wacom technology or something similar from other manufacturer. In short: In the pen have small magnets and coils, that create electromagnetic field with various characteristics, etc...

When the pen works like a mouse, in most cases, it is properly installed. But if it is not, you may follow the article Wacom/Latest Driver from the Ubuntu Community Help Wiki.

You can find which is your device by the commands lsusb and xinput. The output of these commands within my system is:

$ lsusb | grep Wacom
Bus 002 Device 003: ID 056a:00e6 Wacom Co., Ltd

$ xinput | grep Wacom
   ↳ Wacom ISDv4 E6 Pen stylus                  id=10   [slave  pointer  (2)]
   ↳ Wacom ISDv4 E6 Finger touch                id=11   [slave  pointer  (2)]
   ↳ Wacom ISDv4 E6 Pen eraser                  id=16   [slave  pointer  (2)]

Optionally you can use the command lsinput from the package input-utils.

Additionally you can investigate how the device works and which are its characteristics by the command evtest. For example my stylus provides only 255 levels of pressure:The full output is here

$ sudo evtest

Available devices:
...
/dev/input/event5:  Wacom ISDv4 E6 Pen
/dev/input/event6:  Wacom ISDv4 E6 Finger
...
Select the device event number [0-16]: 5

 Input driver version is 1.0.1
 Input device ID: bus 0x3 vendor 0x56a product 0xe6 version 0x111
 Input device name: "Wacom ISDv4 E6 Pen"
 Supported events:
    Event type 0 (EV_SYN)
      ...
    Event code 24 (ABS_PRESSURE)
      Value      0
      Min        0
      Max      255

Don't close the program, just pressing the stylus to the screen and read the result. You shall see lines as these:

Event: time 15.., type 3 (EV_ABS), code 24 (ABS_PRESSURE), value 108
Event: time 15.., type 3 (EV_ABS), code 24 (ABS_PRESSURE), value 58
Event: time 15.., type 3 (EV_ABS), code 24 (ABS_PRESSURE), value 234


Lubuntu 13.04 works, except for unpredictable blank screens

Please check the following instructions:

https://help.ubuntu.com/community/BinaryDriverHowto/Nvidia#Screen_Blanks.2BAC8-Monitor_Turns_Off

Note that GDM was replaced by LightDM.


Cannot run bash script from crontab when it works from command line bash

I note in the crontab(5) man page, this:

  The  ``sixth'' field (the rest of the line) specifies the command to be
         run.  The entire command portion  of  the  line  will  be  executed  by
         /bin/sh  or  by  the  shell  specified  in  the  SHELL  variable of the
         cronfile.

So, you may want to specify bash either with

SHELL=/bin/bash

or, as the above affects all cron scripts, this

* * * * 1-5 root bash /home/xxxxxx/jmeter/VerificationService-0.0.1-SNAPSHOT/jmeter-cron-randomise.sh >> /home/xxxxxxx/jmeter/VerificationService-0.0.1-SNAPSHOT/cron.log
# ...............^^^^


How can I install CUDA on Ubuntu 20.04 to a Dell XPS-15-9570 with GeForce GTX 1050 Ti Mobile?

Here is my solution, which worked at the end of long work and I wanted to document it here.
I followed the instructions on:
https://docs.nvidia.com/cuda/cuda-installation-guide-linux/index.html
There it is specified you should use the kernels 5.4.0, however my kernels were 5.8.0 and when I followed the instructions it didn't worked out. I could install CUDA without any error messages but I couldn't use CUDA, for example in Blender.
You can find 5.4.0 kernels here
https://kernel.ubuntu.com/~kernel-ppa/mainline/v5.4-rc8/
From the long list I took the amd64 generic kernels:
linux-headers-5.4.0-050400rc8_5.4.0-050400rc8.201911171930_all.deb
linux-headers-5.4.0-050400rc8-generic_5.4.0-050400rc8.201911171930_amd64.deb
linux-image-unsigned-5.4.0-050400rc8-generic_5.4.0-050400rc8.201911171930_amd64.deb
linux-modules-5.4.0-050400rc8-generic_5.4.0-050400rc8.201911171930_amd64.deb
When they are downloaded you can install them by running from the download folder:
'''$ sudo dpkg -i cuda-repo-ubuntu2004-11-2-local_11.2.1-460.32.03-1_amd64.deb'''
This page can help you more if you get stuck by reverting to previous kernel:
https://code.luasoftware.com/tutorials/linux/ubuntu-revert-to-previous-kernel/
Following them, I opened the grub with
'''$ sudo nano /etc/default/grub'''
and added this two lines:
'''GRUB_DEFAULT=saved
GRUB_SAVEDEFAULT=true'''
and saved and updated grub with
'''$ sudo update-grub'''
To change the kernel version from 5.8.0 to 5.4.0 you need to enter to Advanced Settings on Grub screen. Grub is the black screen with a list of options appearing after bios, where you can also boot other operating systems. You can actually call it by keep pressing '''SHIFT''' or '''Esc''' However neither worked for me.
To see the grub screen at the start, I needed to edit the grub again and change this line:
'''GRUB_TIMEOUT_STYLE=hidden'''
to this
'''GRUB_TIMEOUT_STYLE=menu'''
then save and update the grub file again of course.
Then change at the Advanced settings menu to the 5.4.0  kernel and now start with the installation instructions as https://docs.nvidia.com/cuda/cuda-installation-guide-linux/index.html


From the commandline I would do (using GetDeb-Packages):

sudo bash -c "echo deb http://archive.getdeb.net/ubuntu lucid-getdeb apps games >> /etc/apt/sources.list"
wget -q http://archive.getdeb.net/getdeb-archive.key -O- | sudo apt-key add -
sudo aptitude install flock


Do all the daemons indicated by configFiles/scripts/links in /etc/{init,init.d} start at the boot?

No, /etc/init.d/ and /etc/init are used to store the startup scripts of various processes used on your system. Having a script in these directory doesn't mean that they are going to start.
For the script in /etc/init.d, there should be a link in one of the /etc/rc*.d directories to start or stop them (symbolic link) managed by the update-rc.d tool.
Services in these directories are usually started / stopped / restarted by the sudo service <service name> <action> command.
For the scripts in /etc/init, these are part of the new boot mechanism offered by upstart. The file in the /etc/init directory contains information about when and how to start and stop the service they offer.
Services in this directory are usually started / stopped / restarted by sudo <action> <service name>.
Of course, less services to start means less time to wait during boot. But take care of not disabling services needed by your system to function properly (like udev, dbus, ...)
For services started from /etc/init.d, the startup script should implement in it various check to report that the service is well started or not. Usually this translate by a line saying " started" or " not started" or some other error message. This appears at the console and should also be logged into /var/log/boot.log.
For services started by upstart (using /etc/init directory), the upstart process itself provides a way to automatically restart services that may fail, manage the dependencies between them (start service1 prior to service2 if service2 needs service1 to start / function).


How can I get my Radeon graphics card to work after upgrading to 16.04?

Solved, there were still fglrx packages installed and I needed to remove them


How to reset libreoffice dictionaries to factory defaults?

While Opening the Liber office

In tools menu ---> Select Options

Under language Settings ----> Select Writing Aids

Delete your Words what ever you have added from the List .


Can the Ubuntu logo be used for a commercial website?

My reading of the Ubuntu trademark policy is that any commercial use requires permission.

  Restricted use that requires a trademark licence

  Permission from us is necessary to use any of the Trademarks under any circumstances other than those specifically permitted above. These include:

  Any commercial use. OEM services
  ...

That said, I imagine that you would get approved for such use. Use this contact form to  request an Ubuntu trademark license


How to get a HP Wi-Fi Touch Mouse X7000 working?

Sorry, but your HP X7000 mouse requires special drivers because it connects over Wi-Fi. HP only has drivers for Windows 7 (see here).


rt3290 wireless not working on Ubuntu 20.04

I had the same problem where the connection would last like 10 min then die. I found that the solution proposed by SinfMaster in this link worked for me https://unix.stackexchange.com/questions/115958/how-do-i-get-a-ralink-rt3290-wireless-card-working-on-debian-jessie


Performance on laptops running very slow

You're not using all of your available RAM. The Ubuntu 64-bit version (the amd64 ISO) is recommended for all computers that have more than 2GB of RAM because it runs faster than the 32-bit version. You should replace your 32-bit Ubuntu install with the 64-bit version.


Ubuntu 12.04 LTS won't install - never finishes please help

It does not appear as though Ubuntu is supported with your hardware according to the official Ubuntu certified hardware list found here:

http://www.ubuntu.com/certification/make/Lenovo/?csrfmiddlewaretoken=8OAcWFmhefE8uYSbG9FS6X8qcd29VrrO&query=lenovo+m57&category=Desktop&category=Laptop&category=Server&release=&level=Any

However, this does not mean that it is impossible to install on this particular unit.

I would first try the alternative install image or maybe even a previous release found here:
 http://www.ubuntu.com/download/alternative-downloads

Are there any error messages that you are receiving while installing?


Do

sudo apt-get install gnome-tweak-tool

Open Advanced settings from Dash .Then Slide the ON option to have file manager handle the desktop


How to install google chrome manually in Ubuntu?

Short answer:
To install software manually you will most likely need to download a .deb file (it's sort of Ubuntu's .msi equivalent), and then either:

Double-click it and install it through the Ubuntu Software Center.

Or:

Use the command-line (I will explain both).

Long answer:
Download Google Chrome here and click:

In order to download the .deb installation file.
It will likely ask you if you want the 32-bit or 64-bit one, download whichever is appropriate for your install, and accept the license agreement.
GUI Installation:
When the download is complete, open your file manager (probably Nautilus) and navigate to the location where you downloaded the file to (probably the ~/Downloads folder).
Then double-click the file, this should open the Ubuntu Software Center, to install click the Install button and then enter your password as prompted (your Ubuntu Software Center may look slightly different to mine in terms of design as I am on the GNOME flavour of Ubuntu):

In the above screenshot I have put a red box around the Install button you need to press.
Terminal Installation:
Now for the command-line Terminal installation, first open a Terminal window (Ctrl + Alt + T), then use the cd command to navigate to the location you downloaded the file to. You will probably need to go to the ~/Downloads folder with:
cd ~/Downloads

And then you will need to run the following command to install Google Chrome where you need to replace [filename] with the name of the file you downloaded. (Either google-chrome-stable_current_amd64.deb(64-bit) orgoogle-chrome-stable_current_i386.deb` (32-bit) ):
sudo dpkg -i [filename]

You will then be prompted for your password (though you will notice that even though it does not look like you are typing anything, in fact you are and this is just a security feature), enter the password and press Enter and that should install Google Chrome.


users created using newusers command unable to login in Ubuntu 18.04

This can happen if the file passed to the newusers command has DOS-style (CRLF) line endings that cause the new user's login shell to be recorded as /bin/bash\r for example.

Ex.

$ cat > singleuser.txt
user_1:password_2:1002:1002:user_1:/home/user_1:/bin/bash

$ unix2dos singleuser.txt
unix2dos: converting file singleuser.txt to DOS format ...

$ sudo newusers singleuser.txt
[sudo] password for steeldriver:

$ sudo su - user_1
: No such file or directory

$ getent passwd user_1 | cat -A
user_1:x:1002:1002:user_1:/home/user_1:/bin/bash^M$

You can fix already existing users using chsh:

$ sudo chsh -s /bin/bash user_1
$ sudo su - user_1
user_1@xenial-vm:~$