How compress rar with context menu nautilus

Unfortunately, the nautilus extension for fileroller, which now provides the right-click option and the dialog, indeed does not anymore support the creation of alternative archive formats, even if the supporting application is installed. You will need to resort to an alternative approach.

1. Use fileroller directly

Fileroller itself still maintains the rar support. Thus, you can open fileroller (search for "Archive Manager" or "fileroller") and create the rar archive from there.

2. Create your custom right-click menu item for rar

If you prefer having a right-click menu item, then you can explore one of several options to add custom right-click menus to Files (nautilus).

2.a Nautilus scripts: You can create nautilus scripts which can be started from the right-click menu. These scripts live in ~/.local/share/nautilus/scripts/. Scripts that are set 'executable' will appear in a new "Scripts" submenu of your right-click menu. How this is easily done is indicated in How do I make nautilus use file-roller in Ubuntu 18.04 and above like in 17.04? (Thanks to TiTAN for the hint!)

2.b Filemanager-actions or nautilus-python: Other possibilities are outlined in this Ask Ubuntu question. Look for "Update for Ubuntu 18.04" for the application filemanager-actions, and the answer of mnrl for relying on python-nautilus.


This is how I enabled Ubuntu 13.04 to install alongside Windows 8 with a new (May 2013) Lenovo IdeaPad Y500 (1TB drive, dual NVidia GT 750M).

1) Download a copy of Ubuntu 13.04 x64 desktop ISO and install to a USB flash drive.  (http://www.ubuntu.com/download)  Create the USB install image following this guide (https://help.ubuntu.com/community/Installation/FromUSBStick)

2) Resize your Windows 8 partition using the built in Windows drive management tool.  Just resize the partition down, don't create a new partition in the empty space as the Ubuntu installer will do that.  (You may need to do a complete reboot for the resizing to take place.)

3) While still in Windows 8, edit the boot/grub/grub.conf on the new USB flash drive using Wordpad.

Change where it says "set gfxmode=auto" to "set gfxmode=1920x1080"

Under "Install Ubuntu", change "quiet splash" to "nomodeset=1"

So it should look something like this:

if loadfont /boot/grub/font.pf2 ; then
    set gfxmode=1920x1080
    insmod efi_gop
    insmod efi_uga
    insmod gfxterm
    terminal_output gfxterm
fi

set menu_color_normal=white/black
set menu_color_highlight=black/light-gray

menuentry "Try Ubuntu without installing" {
    set gfxpayload=keep
    linux   /casper/vmlinuz.efi  file=/cdrom/preseed/ubuntu.seed boot=casper quiet splash --
    initrd  /casper/initrd.lz
}
menuentry "Install Ubuntu" {
    set gfxpayload=keep
    linux   /casper/vmlinuz.efi  file=/cdrom/preseed/ubuntu.seed boot=casper only-ubiquity nomodeset=1 --
    initrd  /casper/initrd.lz
}
menuentry "OEM install (for manufacturers)" {
    set gfxpayload=keep
    linux   /casper/vmlinuz.efi  file=/cdrom/preseed/ubuntu.seed boot=casper only-ubiquity quiet splash oem-config/enable=true --
    initrd  /casper/initrd.lz
}
menuentry "Check disc for defects" {
    set gfxpayload=keep
    linux   /casper/vmlinuz.efi  boot=casper integrity-check quiet splash --
    initrd  /casper/initrd.lz
}

4)  Install Ubuntu and choose the option to install Ubuntu 13.04 alongside Windows 8.  Choose to install the bootloader onto your new Ubuntu partition.

5)  After the install is complete, boot again with your USB and select "Try Ubuntu" and let it boot to the text console.

You will not be able to use this new Ubuntu install until you edit this grub.cfg as well.  To do this, first mount this new partition, and then edit the grub.cfg as above in the Ubuntu editor of your choice (vi, nano, etc).

sudo mkdir /mnt/newinstall
sudo mount /mnt/newinstall /dev/sdb8
sudo vi /mnt/newinstall/boot/grub/grub.conf

(Same edits as listed in step 3.  Also on my install Ubuntu was on the 8th partition /dev/sdb8. Yours may vary so check it first!)

** Note the file is write protected, so make sure you use ":w!" to write from vi.

6) At this point you should be able to boot your new Ubuntu, but you will only be greeted with a hopefully legible text console.  The default VESA and nouveau drivers do not support the 750M cards.  In addition the Ubuntu provided nvidia binaries are also too old and will not work.  (Well I spent several hours without success trying to get them to work.)  The solution:

Install the new drivers from NVidia! (please visit the NVidia website and find the relevant driver URL.  I have listed the one current as of 2013-May-6):

wget http://us.download.nvidia.com/XFree86/Linux-x86_64/319.17/NVIDIA-Linux-x86_64-319.17.run
sudo chmod +x NVIDIA-Linux-x86_64-319.17.run
sudo sh ./NVIDIA-Linux-x86_64-319.17.run
(follow the installer instructions)

7) You should now have both a functional Windows 8 and Ubuntu 13.04!  I would love for the Ubuntu supported nvidia drivers to work, as any kernel Ubuntu updates will force me to have to re-install the nvidia binary drivers.

8) Choose your boot method.  You can select "F12" while booting to choose what to boot.  To set a default, hold "F2" while booting and you can reorder the boot priority.


How to add a low-pass filter to a system-wide PulseAudio profile?

PulseAudio Profiles

The system-wide default PulseAudio profile is configured in /etc/pulse/default.pa and overridden by per-user profiles in ~/.pulse/default.pa if the latter exists. PulseAudio profiles consist of a series of commands issued to the PulseAudio daemon.

To apply a new configuration one needs to restart the PulseAudio daemon:

pulseaudio --kill
pulseaudio --start

If the daemon doesn't start after a configuration change you can run PulseAudio un-daemonized if you leave out the --start option and you can elicit debugging information with --log-level or one or more -v options, e. g.:

pulseaudio --kill
pulseaudio --log-level=info

Instead of restarting the PulseAudio daemon you can also change its configuration and (un-)load modules through direct commands via pactl or pacmd. This is often easier than restarting the daemon all the time for minor changes.

Module Loading

To add a module use the load-module command. You can find a PulseAudio-compatible low-pass filter in Ubuntu's package repositories in the form of the LADSPA plug-in lowpass_iir_1891 in the package swh-plugins and available to PulseAudio through the module-ladspa-sink module. The full command looks like this:

load-module module-ladspa-sink plugin=lowpass_iir_1891 label=lowpass_iir master=<MASTER_SINK> sink_name=<NAME> [control=<FILTER_PARAMETERS>] [channel_map=<CHANNEL_MAP>] [channels=<CHANNEL_COUNT>]

where <MASTER_SINK> is the name of the down-stream "sink" that receives the audio data from the filter1 and <NAME> is the name of the sink that the filter module represents. <FILTER_PARAMETERS> is used for things like the cut-off frequency and steepness. For the other parameters and more details see the PulseAudio Wiki entry on modules.

Setting a Default Sink

Now if you want all applications to use the filter sink by default you need to inform PulseAudio like this:

set-default-sink <NAME>

where <NAME> is the same as in the previous section.

PulseAudio stores the last sink of each application using it and may use that in favour of the new default. To reset those remove ~/.pulse/*-stream-volumes.tdb. You can also configure the per-stream sink with tools like pavucontrol (GUI) or pactl move-sink-input (command-line).

1 You can list all sinks with pactl list short sinks. Your actual audio device sink name will usually consist of alsa_output, the device path and the channel profile name, e. g. (on my system) alsa_output.pci-0000_00_1b.0.analog-stereo.


This likely means that another instance of mongodb is already running. You can use the following command to restart it:

  sudo service mongod restart


how to disable ALT for showing the shortcut of menu on ubuntu16.04

You could try to modify the Alt key behavior using gnome-tweaks.

For Ubuntu 18.04 and after :

Install gnome-tweaks and start it:

sudo apt install gnome-tweaks
gnome-tweaks

Go to Keyboard & mouse -> Additional Layout Options (refered as Options supplémentaires d'agencement on my screenshot) -> Alt and Super keys behaviors (or Alt and Windows keys behaviors)
Choose the behavior for Alt key as you want to define it.

If you just want to remove Alt shortcuts, don't use gnome-tweaks as refered before, just modify each shortcuts in Settings -> Keyboard


Time Machine config (Late 2020) - need for Avahi? Using Docker as best practices?

Fot the avahi part that is an interesting question. I didn't know so I ran some tests:
First I wanted to see if avahi was a compiled option in samba:
~$ smbd -b | grep AVAHI
   HAVE_AVAHI_CLIENT_CLIENT_H
   HAVE_AVAHI_COMMON_WATCH_H
   HAVE_AVAHI_CLIENT_NEW
   HAVE_AVAHI_STRERROR
   HAVE_LIBAVAHI_CLIENT
   HAVE_LIBAVAHI_COMMON
   WITH_AVAHI_SUPPORT

It would appear that it is.
So I figured the only way to confirm this is to disable avahi-daemon.
Note: You can't just "stop" or "disable" the service because cups-browse will just start it up again so you have to mask it:
sudo systemctl mask avahi-daeemon

Then I had to reboot the server.
I could no longer "see" the ubuntu server from the Mac or connect to it with a smb://hostname.local ...
Looks like avahi is a requirement to me.
Note: I needed to "unmask" the service and restart it to restore things:
sudo systemctl unmask avahi-daemon
sudo systemctl restart avahi-daemon


imapsync on 16.04 Xenial (on a fresh/basic install) do:

 sudo apt-get install libio-tee-perl
 sudo apt-get install libmail-imapclient-perl
 sudo apt-get install libterm-readkey-perl
 sudo apt-get install libunicode-string-perl

 ## The rest is optional I believe:

 sudo apt-get install libcrypt-openssl-rsa-perl
 sudo apt-get install libauthen-ntlm-perl
 sudo apt-get install libdata-uniqid-perl
 sudo apt-get install libjson-perl
 sudo apt-get install liblwp-online-perl

 ## For Xenial/16.04 I could not locate these packages nor would 'cpan'
 ## work for me - but you could try (as user running imapsync):
 cpan install JSON::WebToken
 cpan install Filesys::DfPortable

Then test:

 ./imapsync --dry --host1 localhost --user1 1@localhost --password1 1 --host2 localhost --user2 2@localhost --password2 2

You should see a module list within the error output:

Modules version list:
Mail::IMAPClient     3.38
IO::Socket           1.38
IO::Socket::IP       0.37
IO::Socket::INET     1.35
IO::Socket::SSL      2.024
Net::SSLeay          1.72
Compress::Zlib       2.068
Digest::MD5          2.54
Digest::HMAC_MD5     1.01
Digest::HMAC_SHA1    1.03
Term::ReadKey        2.33
File::Spec           3.56
Time::HiRes          1.9726
Unicode::String      2.09
IO::Tee              0.64
File::Copy::Recursive 0.38
Authen::NTLM         1.09
URI::Escape          3.31
Data::Uniqid         0.12
JSON                 2.90
JSON::WebToken       ?
Crypt::OpenSSL::RSA  0.28
LWP                  6.15
HTML::Entities       3.69
Filesys::DfPortable  ?

I can confirm the imap sync worked using the above package installs on 14.04/16.04 Dovecot systems using TLS. As I mentioned, you may only need the first ones listed to get it working at a basic level. The perl modules needed should be basically the same under 14.04 fresh install.


How to install ubuntu restricted extras but not flash?

Restricted extras is a metapackage

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

A metapackage is not a single package, but rather a list of packages.

The idea is to make it easier for you, rather then installing each individual package, you install the metapackage.

To see the list of packages in restricted extras see

http://packages.ubuntu.com/precise/ubuntu-restricted-extras

which points to

http://packages.ubuntu.com/precise/ubuntu-restricted-addons

So ...

sudo apt-get install gstreamer0.10-ffmpeg gstreamer0.10-fluendo-mp3 gstreamer0.10-pitfdll gstreamer0.10-plugins-bad gstreamer0.10-plugins-ugly gstreamer0.10-plugins-bad-multiverse libavcodec-extra-53 ttf-mscorefonts-installer unrar


help loading Ubuntu along side Windows xp

Boot to the Linux DVD that you burned and follow the installation prompt.  Choose the option to install along side Windows.  Continue to follow the prompt.

The installation is very automatic.  When the installation is complete and you reboot the computer you'll see an option to either boot into Windows or boot into Linux.

By the way the "pagefiles.sys" file is a windows component that has nothing to do with Linux.  None of the other steps that you mention has any thing to do with the actual installation.  You'll have to boot to the disk to perform the installation.

By the way, that is the same way you install Windows.  You boot to the installation disk.


If you want filesystem information and not partition/volume information, I think you'll have to use filesystem-specific tools.

In the case of the extN systems, that would be dumpe2fs. And dumpe2fs doesn't directly print the size in bytes, as far as I can tell. It does, however, print the block count and the size of blocks, so you can parse the output instead:

$ dumpe2fs -h /dev/sda1 |& awk -F: '/Block count/{count=$2} /Block size/{size=$2} END{print count*size}'
29999980544

In my case, this size is slightly different from the partition size:

$ parted /dev/sda u b p
Model: ATA ST500LT012-1DG14 (scsi)
Disk /dev/sda: 500107862016B
Sector size (logical/physical): 512B/4096B
Partition Table: gpt
Disk Flags:

Number  Start          End            Size           File system     Name  Flags
 1      17408B         30000000511B   29999983104B   ext4                  boot, esp
 2      30000807936B   453049843711B  423049035776B  ext4
 5      453049843712B  495999516671B  42949672960B   ext4
 3      495999516672B  500102862847B  4103346176B    linux-swap(v1)
 4      500102862848B  500107845119B  4982272B                             bios_grub

The partition size is 29999983104 bytes, 2560 bytes more than a multiple of the block size, which is why the size reported by dumpe2fs is less.


After installed the second graphic card, I used this command to create new xorg.conf and it works.

sudo aticonfig --adapter=all --initial

After that if you want to move windows over the screens, enable the Xinerama.


Cannot find hard drives after installing Ubuntu 13.10

If you choose "Erase everything and install Ubuntu" option, your whole disk will be erased, which means your disk will be formatted. If there are multiple disks in your computer the "Erase everything and install Ubuntu" option will only erase the selected disk, but it won't erase the other disk(s). Then the installer installs Ubuntu on a created ext4 partition and then it also creates a separate SWAP partition on the extended partition according to the swap size given. On new installations of Ubuntu 17.04 and later a swap file will be created instead of a separate swap partition.


I'm no expert, but maybe this will help. There are two different times used by linux, UTC and your local time based on your time zone. UTC is the same for everyone, local times change with location. When setting times, make sure you know how the program will interpret the time you are giving it.

When I set repetitive tasks, I like to set the crontab myself with the editor rather than changing the daily or weekly folders. From the terminal, type:

 sudo crontab -e

And add your commands to this table directly. This way, all of the user's repetitive commands are held in one place. The default file contains instructions on how to make an entry, but the manpages for crontab have a more in depth description. You are editing it with nano, so make sure you get the hang of this as well.


The part before the $ in a shell is called prompt. It can be configured by changing the variable $PS1. There are is a similar question with good answeres.

The man page (see "Bash" and there "PROMPTING") says:

      \w     the  current working directory, with $HOME
             abbreviated with a tilde (uses the value of the
             PROMPT_DIRTRIM variable)
      \W     the basename of the current working directory,
             with $HOME abbreviated with a tilde

So you have to change \w to \W. Probably the initial value for $PS1 is stored in your .bashrc, that means you have to edit the file ~/.bashrc and you will find lines similar to:

if [ "$color_prompt" = yes ]; then
    PS1='${debian_chroot:+($debian_chroot)}\[\033[01;32m\]\u@\h\[\033[00m\]:\[\033[01;34m\]\w\[\033[00m\]\$ '
else
    PS1='${debian_chroot:+($debian_chroot)}\u@\h:\w\$ '
fi
unset color_prompt force_color_prompt

Change \w to \W in both lines and open a new terminal (or run source ~/.bashrc).


Why can't I see my published app in the Ubuntu Software Center?

You mean this Byte browser?

You created a click package and uploaded it to the click store. It will never appear in the Ubuntu Software Center, as that is for traditional Debian packaged applications. Apps packaged as clicks will appear in the click store scope in Unity8.

If you wish to ship your application in Ubuntu Software Center, you will need to create a traditional Debian package, following the guidelines on the developer site. You can upload the package through that site.

If your application is not suitable for use on phones and tablets, you might want to remove the click application you uploaded, from the store, so that others don't install it and end up with an app which doesn't work on their devices.


conjure-up error ubuntu 16.04 - neutron-gateway config-changed

You could add "net.ifnames=0" on kernel boot parameters (MAAS settings) and check the name consistency of MAAS nodes' interfaces.

Running conjure-up, using openstack with NOVAKVM spell you can enter the configure option on neutron-gateway unit, section "data-port" and change the default interface value (eno2) to one of the interfaces of your MAAS nodes.

Maybe it´s worth to check:
https://bugs.launchpad.net/conjure-up/+bug/1626941
and
This link under "Port configuration" section.

No sure if ceph-OSD issues are related to the neutron-gateway one.


Explain different Ubuntu versions to a new user? (Stable, LTS, 20.04)

First off, let me welcome you to Ubuntu as well as Linux community. I'm elated that you're having the intentions to teach Linux to your young son (I wish I'd have picked linux that early in my life).

My answer is based on the assumption that you're a new Linux user, and the primary intent is to use your machine for home (causal) computing.

Given below are few points(I wish I'd have know when I started) which I hope would be enough to give you the right direction, from where you can chose to make your preferred opinion:

Linux world is vast, and presents a gazillion options to chose from. Most of the times, instead of empowering a 'new user', this plethora of choices overwhelm the user to go back to the familiar world of Windows. Don't overwhelm yourself.
One of the goals with which Ubuntu is developed is to not overwhelm the users, and just get them starting. Ubuntu has several flavours (Lubuntu, Kubuntu, etc) which offer different Desktop Environments (DE). In crude terms, Consider DE as a skin/wrapper to present you with a User-Interface to the underlying system which is same for all flavours. Underlying system is easily accessed via command line (terminal).

There are other distributions, few based on Ubuntu itself, which are trying help  Windows users migrate seamlessly to linux. One such distribution is Linux mint.

Most likely you've chosen a stable version (Unless your downloaded .iso file has beta/alpha in its name). Read until the end to find about the command lsb_release -a
A stable version is ready for public use. Depending on how long they'll receive updates (feature/security/bug-fixes), There are 2 types of stable releases Ubuntu offers.
Windows software won't work on linux due to different architecture. This doesn't mean that you don't have alternatives. Most times than not, your Ubuntu will already have pre-installed softwares for what you're trying to achieve. Additionally, you can search the name of an Ubuntu equivalent software for the task you're trying to achieve. Chances are you'll find an open-source, free, stable, and easy to install alternative that just works.

Consider upvoting and accepting my answer if it helped.


Your question looks really broad, however just to mention that "Ubuntu has pre installed firewall and a Set of Rules what so called "IPTABLES".

You can do

  sudo ufw status        #this gives you the status if firewall is active or inactive

or

  sudo ufw enable   #enables the firewall

or

  sudo ufw -h #displays all possible options

To enable the firewall just type  sudo ufw enable ssh #this will enable firewall for ssh.

You can add some rules using iptables Command

  sudo iptables -L -n #will list available rules for IPTABLES such as (INPUT, OUTPUT,NAT,etc.)


The easiest way to ensure you have no two instances of your PHP script running would be IMHO to write a tiny wrapper script in Bash that kills any currently running instances of your exact command before running it.

You can then execute this wrapper script in your cronjob instead of the actual PHP command.

Possible wrapper implementation:

#!/bin/bash

my_command='php -f /var/webserver/public_html/cron/scheduled_job_1.php'

# kill processes with the exact command line as above, if any are running
if pkill -fx "$my_command" ; then
    # You can do something here, which runs only if a process was killed.
    # The command below would just echo a warning to the terminal (not visible as a cronjob)
    echo "$(date) - WARNING: Previous instance of '$my_command' was killed."
fi

# (re)run the command
$my_command

Or a generic wrapper that expects the command to run as argument.

#!/bin/bash
# This script expects a command as argument(s), like e.g. "my_wrapper sleep 60"

# kill processes with the given command line, if any are running
if pkill -fx "$*" ; then
    # You can do something here, which runs only if a process was killed.
    # The command below would just echo a warning to the terminal (not visible as a cronjob)
    echo "$(date) - WARNING: Previous instance of '$*' was killed."
fi

# (re)run the command
"$@"

If you save it e.g. as /usr/local/bin/my_wrapper, you can call it like

my_wrapper php -f /var/webserver/public_html/cron/scheduled_job_1.php


Connect to the internet using your phone. You can connect almost any phone by USB and use it as a modem.

Then run in a terminal

sudo apt update
sudo apt install bcmwl-kernel-source

With the 18.04 Ubuntu version it is not very straight forward to install Broadcom drivers offline.


PowerTop showing BAD status in SATA Link and PCI Device

You can optimize each of those settings for low power consumption (Good) instead of potentially better performance (Bad) by pressing Enter while they are highlighted in interactive mode.

Alternatively, PowerTOP can automatically tune all settings for low power usage if you run the command

sudo powertop --auto-tune

Whether the Good (lower power usage) or Bad (maybe higher performance) settings or a specific combination of those are more suitable for you depends on whether you need long battery life or high performance more. The decision is up to you.


How to fix "W: Duplicate sources.list entry"?

Your sources.list really has duplicate entries.

First Let's see the correct form of a repository line or source line:

The correct format of repository source line is

<type of repository>  <location>  <dist-name> <components>

For example, a repo line can be like this one

  deb http://archive.ubuntu.com/ubuntu precise main

Here, it means, the repository is for binary packages, which are hosted in http://archive.ubuntu.com/ubuntu and this repository is for Ubuntu precise (12.04) and this repository contains the main (software which are officially supported by Canonical) component.

Type: The type can be deb and deb-src. deb means a binary repository where deb-src means a source repository
Location: http://archive.ubuntu.com/ubuntu location of the repository.
Dist-name: The distribution name of Ubuntu release. For Ubuntu 12.04 it is precise, for 11.10 it is oneiric.
You can visit the Ubuntu Wiki to view an updated list of Ubuntu releases and their code names.
Component: It can be main, universe, multiverse and restricted. These words indicates the level of supports for the packages and the licensing status.

See this page for more information.

Please take note that, you can add one or more component in a line, so "main", "universe", "restricted" and "multiverse" can be in a single line. Also note, Though you add more than one component in a single line, APT system considers them as separate line containing only one component.

So, If your sources.list have a line like this

deb http://archive.ubuntu.com/ubuntu precise universe

Then it can't have another line like the below (which your files have)

deb http://archive.ubuntu.com/ubuntu precise main universe

which is equivalent of these two lines

deb http://archive.ubuntu.com/ubuntu precise main
deb http://archive.ubuntu.com/ubuntu precise universe

Because, you are duplicating universe twice, so there will be an error for that duplicate. An error will be given for each duplicate found.

Solution:

After analyzing your sources.list file, I found that, It is a basic one which is supplied by Ubuntu by default. You can build a default file following the procedure:

Open a terminal and first rename the existing sources.list file to sources.list.bak file. (we can safely remove that, but caution is good).

 sudo mv /etc/apt/sources.list /etc/apt/sources.list.bak

Then open software-properties-gtk to build a new one. Type the below command in a terminal or in dash command prompt with pressing Alt+F2

software-properties-gtk

Note, for Ubuntu version 11.10 or earlier you have to use gksu before the software-properties-gtk command
After the window is open,

Select all four categories in Ubuntu Software tab
Select  precise-security, precise-updates and precise-backports category in Updates tab.
Select Canonical partner and Independent category from Other software tab.

That's it. You have now a default sources.list file without error. Compare this file with the previous one, if you want.

Update to deal with sources.list.d dir's files

Sometimes a duplicate entry can be in a file in the /etc/apt/sources.list.d directory, which is also used by APT. So, you should look at that directory and see if there is any duplicate in those files. It is not necessary for duplicates being in the same file.

Example case:

A user had this error message showing while doing sudo apt-get update.

W: Duplicate sources.list entry http://dl.google.com/linux/chrome/deb/ stable/main amd64 Packages (/var/lib/apt/lists/dl.google.com_linux_chrome_deb_dists_stable_main_binary-amd64_Packages)
W: Duplicate sources.list entry http://dl.google.com/linux/chrome/deb/ stable/main i386 Packages (/var/lib/apt/lists/dl.google.com_linux_chrome_deb_dists_stable_main_binary-i386_Packages)
W: You may want to run apt-get update to correct these problems

But there was no entry with http://dl.google.com in the main /etc/apt/sources.list file. Looking at the /etc/apt/sources.list.d/ directory we found these files:

output of ls /etc/apt/sources.list.d/:

aims-sagemath-precise.list
aims-sagemath-precise.list.save
dropbox.list
dropbox.list.save
fossfreedom-packagefixes-precise.list
fossfreedom-packagefixes-precise.list.save
google-chrome.list
google-chrome.list.save
google.list
google.list.save
sagemath-monolithic-precise.list
sagemath-monolithic-precise.list.save

The files google-chrome.list and google.list were good candidates for containing duplicates. So, checking the contents of both files was necessary.

Output of cat /etc/apt/sources.list.d/google-chrome.list:

deb http://dl.google.com/linux/chrome/deb/ stable main

and of cat /etc/apt/sources.list.d/google.list

deb http://dl.google.com/linux/chrome/deb/ stable main

So, there was a duplicate entries in the sources of Apt. Since google-chrome.list only contain a single apt line and it was also listed in google.list file we can safely remove this file with the command

sudo rm /etc/apt/sources.list.d/google-chrome.list

Then the problem was solved.


trying to install Node js, but it seems like in the source files or package there in an extra space so error are there

If you want to install node.js you should install it via apt:

sudo apt-get install nodejs

You can list further node.js packages with following command:

apt search nodejs

Using the command

nodejs -v

you can check the installed verison.


Create deb repository with several versions of the same package

As far as I understand, mini-dinstall requires debian .changes files when adding packages. As I only had .deb files available I found that aptly supports multiple versions as well.

Another more light-weight option is freight which is a set of shell scripts for maintaining a debian repository. I have now (2017) been using freight for three years to maintain a small but actively updated repository, with good results. One key feature was the ability to keep multiple versions of a package.

Edit: Updated link to new freight repo as the previous had not been updated since 2014.


will downloading ubuntu erase windows? And what will happen to my files (pictures, documents etc.)

There is substantial documentation on dual-booting Ubuntu with Windows which I strongly recommend if you are new to Linux because it allows you to boot your old system if needed.

By the time you're ready for your second Ubuntu installation, you'll probably realize that you don't need Windows except possibly as a gaming platform.


While this doesn't directly answer your question, you might want to consider a program called Synergy. It allows you to use one mouse/keyboard across all three computers. That way you can still take advantage of the cpu power on the laptops instead of just using them as a remote display. Imagine running a torrent client on a laptop along with a browser to display stuff while coding/writing papers while keeping the cpu of your main machine free to do other things. It is also useful to have one laptop running windows for programs that don't play nice with wine. Sure you could use virtualbox, but a physical windows machine can be nice to have at times.


how to resolve "TypeError: Cannot call method 'push' of null"

You made a small mistake in naming your Pagestack component:

PageStack {
    id: pagestack

Later you're calling it with pageStack.push. To work correctly you just need to rename your component id (with a capital S):

PageStack {
    id: pageStack


How to install Python 3.4 properly on Saucy?

Too late for you, probably, but in case this is useful for anyone else... here's how to take advantage of the fact that Python 3.4 is in the Trusty repositories. Not sure if there are problems with this method but it's working for me.

Set your preferred release to Saucy (to prevent problems from what we're about to do next):

sudo echo 'APT::Default-Release "saucy";' >> /etc/apt/apt.conf.d/01ubuntu

Add Trusty to your sources.

sudo echo 'deb http://archive.ubuntu.com/ubuntu trusty restricted main multiverse universe' >> /etc/apt/sources.list

If all is working properly, you should be able to manually install packages from Trusty, but only for packages that don't exist for Saucy. To double-check nothing got screwed up, make sure apt doesn't want to upgrade 500 packages.

sudo apt-get update
sudo apt-get dist-upgrade

If there are many many packages that want to upgrade, something went wrong. Press 'N' to cancel the upgrade. Roll back your changes and try again or post here in case I'm not explaining this right, maybe someone else can help figure out what's going on.
If all is going to plan, you should now be able to install python 3.4.

sudo apt-get install python3.4 python3.4-dev python3.4-dbg python3.4-doc


Looks like you typed "dhcp" to me. Change this:

broadcast-dchp-discover

To use dhcpd:

broadcast-dchpd-discover


Upgrade 14.04 to 16.04 went wrong with dependency & exit status 127 errors

I've installed Ubuntu 18.04.1 from scratch. I think there were too many errors to be able to solve this.


When trying to mount an E01 image in terminal using ewfmount, it says "Unable to create fuse channel". What do you think is the problem

It appears you are trying to mount to a non-empty folder. If you create a folder within your /mnt folder (i.e. /mnt/e01Raw/), then you should be able to run ewfmount and get the raw stream.

sudo mkdir /mnt/e01Raw
sudo ewfmount CFReDS001.EO1 /mnt/e01Raw


Of course running rsync via cron job is an option, but it is NOT the best option.

You can try BitTorrent Sync (AKA btsync), download and run btsync on both your old netbook and NAS (most likely to be running ARM Linux), set up folder to sync on the old netbook, add then add it (use the secret or QR code) on the NAS to sync it over. Works like a charm.


Parts of this answer come from: How do I feed Skype a prerecorded video?
Sure you can.
You can use the Webcam Studio, which will allow you to use pre-recorded media, such as images, audio/video, etc. as a source to create a virtual "bridge" between your live streams (webcam, digital cameras/players, etc.) and other media.
I have used this for both Skype and Flash/Web Based Services like Ubiqq (http://www.ubiqq.com) and Ustream.TV (http://www.ustream.tv/) As shown in the provided screenshots.

This screenshot shows the usage of the Virtual Video Device from WebcamStudio on ubiqq. Which is a flash/web based video conferencing system.
Webcam Studio will allow you to choose both live and pre-recorded media, and enrich it with effects which includes animations, text, and further more.
Good luck!


What does Ubuntu offer me while using a Chromebook?
Ubuntu can offer everything it has to offer in general when installed in a Chromebook.
There are two popular ways of installing Ubuntu on a Chromebook known as Chrubuntu and Crouton. Only Chrubuntu uses the official version of Ubuntu. Under some conditions one can install standard Ubuntu without using either scripts. For this answer I will consider a standard stand-alone Ubuntu installation. That is, the situation where the default ChromeOS is completely replaced by Ubuntu.
Most of these will also apply for a dual boot using the Chrubuntu script.
Note: the Crouton install method uses the ChromeOS kernel and thus is not an official version of Ubuntu. This answer does not apply to Crouton.
Advantages

Unlike ChromeOS, Ubuntu does not depend as much on having an Internet connection for most tasks. For example, one can write a poem or some programming codes in Ubuntu while there is no internet. To be fair, some of these things can be done without the Internet in ChromeOS as well.

If you are used to all the software that works in Ubuntu, they will work in Ubuntu installed in a Chromebook. For example, you can use Skype (if you care about Skype) in Ubuntu in a Chromebook, you can't do that with the ChromeOS.

You can use the Chrome browser in Ubuntu installed in a Chromebook. This means anything that can be done in a standard Chromebook, can be done with Ubuntu on a Chromebook.

Disadvantages

Ubuntu won't install or work on all Chromebooks. Only Chromebooks with Intel processors work well with Ubuntu. However, some of the Intel Chromebooks don't work at all as they can't be booted into Legacy mode.

Installing Ubuntu in a Chromebook will void the warranty. And installation isn't easy. Depending on the version of Ubuntu and the make and model of the Chromebook, some parts may not work at all or not work well without further tinkering.

Chromebooks are not designed for Ubuntu. In particular, Chromebooks come with either 16GB or 32GB of internal storage. If you replace ChromeOS with Ubuntu there is enough space for a standard Ubuntu install. However, there may not be enough space for your music, video etc. in the internal storage. Replacing the internal SSD with something bigger may or may not be possible depending on the make and model. If you want to dual-boot ChromeOS and Ubuntu, you may want to buy a bigger SSD and replace the original one.

Similarly, Chromebooks come with either 2GB or 4GB of RAM. In most models the RAM is not up-gradable. So, if you want to use an app in Ubuntu that needs a lot of RAM, this will not work for you.


Does enabling and configuring Secure Boot offer no additional security benefit in Ubuntu?

That is indeed true. On Windows, secure boot can offer additional benefits, as noted by NCSC:

  The Early Launch Anti-Malware (ELAM) driver provides signature
  checking for known bad drivers on ELAM compliant systems that are
  configured to use Secure Boot.

  ...

  The Windows 10 Secure Boot process (on supported and correctly configured
  hardware) alerts a user when an attempt to subvert the security
  controls has taken place. It is important that users know how to
  identify and respond to this alert.

Neither feature is available on Ubuntu that I am aware of.


apt-get not finding valid package to install

The problem here is the following - the nvidia-graphics-drivers-430 is the name of source package, but the main binary is named simply nvidia-430 - check this page on PPA.

So you can use command below to install Nvidia 430:

sudo apt-get install nvidia-430

or install them using GUI from 5th tab of Software & Updates (software-properties-gtk) named Addtional Drivers.


How can I backup my computer hard drive?

Roland,

You can mix applications from different Ubuntu flavors, and even have 2 or more interfaces side by side.
http://www.ubuntu.com/about/about-ubuntu/flavours

sudo apt-cache search burning | grep -i cd/dvd
# It will give you some options
# brasero - CD/DVD burning application for GNOME
sudo apt-get install brasero

My favorite is Brasero, it is straightforward and a rock solid software.


Found this solution on Launchpad which works:

https://bugs.launchpad.net/ubuntu/+source/linux/+bug/906832

ASUS USB-BT400 USB Adapter w/ Bluetooth 4.0 - Ubuntu Linux 13.04 - Fix

sudo su -
modprobe -v btusb
echo "0b05 17cb" >> /sys/bus/usb/drivers/btusb/new_id


The only current version of Ubuntu this works for is 12.04 and the repos haven't been updated since 2013. Don't use it.
For 14.04+, please see the second answer.

Copy the following Kali repositories:
deb http://ppa.launchpad.net/wagungs/kali-linux2/ubuntu YOUR_UBUNTU_VERSION main
deb-src http://ppa.launchpad.net/wagungs/kali-linux2/ubuntu YOUR_UBUNTU_VERSION         main
deb http://ppa.launchpad.net/wagungs/kali-linux/ubuntu YOUR_UBUNTU_VERSION main
deb-src http://ppa.launchpad.net/wagungs/kali-linux/ubuntu YOUR_UBUNTU_VERSION main

Replace the text YOUR_UBUNTU_VERSION based on your Ubuntu version.

Ubuntu 12.04: precise
Ubuntu 12.10: quantal
Ubuntu 13.04: raring

Assuming that you are using Ubuntu 13.04, your repositories would be
deb http://ppa.launchpad.net/wagungs/kali-linux2/ubuntu raring main
deb-src http://ppa.launchpad.net/wagungs/kali-linux2/ubuntu raring main
deb http://ppa.launchpad.net/wagungs/kali-linux/ubuntu raring main
deb-src http://ppa.launchpad.net/wagungs/kali-linux/ubuntu raring main

Note: If you're an Ubuntu 14.04 user, you can use raring, as Trusty version of Kali repositories are not released
Update sources
Open your sources using the command
sudo -H gedit /etc/apt/sources.list.d/kali-tools.list

Now, gedit editor will open the file kali-tools.list. Paste the above code at the end of your file and Save.
Copy the PGP Key
Copy the Key below and save it as key.pgp text file in your desktop.
-----BEGIN PGP PUBLIC KEY BLOCK-----
 Version: SKS 1.1.4
 Comment: Hostname: keyserver.ubuntu.com

 mI0ET324YwEEANbSlISrOlAGjxgFRxiN6jk0JIl/vxQ8lapRdxZ4DHDAQdXbX4AuigMBkP5e
 sOxhMpDnkgMRtEVpaBMdQheA0/431pPQYqkr3jdeZw5JS5opiyJ4qr/QrcoSFHSluEkWkbZ6
 RYOkA25vW31KK2FB2LQVRYk580llXAVgIUznm2ATABEBAAG0GExhdW5jaHBhZCBQUEEgZm9y
 IHdhZ3VuZ4i4BBMBAgAiBQJPfbhjAhsDBgsJCAcDAgYVCAIJCgsEFgIDAQIeAQIXgAAKCRAb
 IuuNj9/bVxabBADSGN8cp+hqkdZqwq263wdz/UGsiuB1bCrH06/HznC/ZC5rjfH3aQ1Dwwag
 zYCrSD3c0cKNAqD10009N76RMlzZBH8kKL9khH3zPL/k4/lYuVP7y6NKFbBsnawEUc0mWcCa
 mH4ScTdWWPXP/mOQiUUjnQ1bZhzpcbQOb+hEUAqExg==
 =fJ+8
 -----END PGP PUBLIC KEY BLOCK-----

Add PGP Key in apt
Open terminal and type
cd Desktop
sudo apt-key add key.pgp

If your key addition is successful, you will see Ok.
Now update your apt-get repositories using the command
sudo apt-get update

Install Synaptic Package Manager
Use the command
sudo apt-get install synaptic

If you already have Synaptic installed, you may skip this step.
Install Kali Tools
Now open Synaptic Package manager and click on Origin. You can see 2 Kali repositories by names
LP-PPA-wagungs-kali-linux/raring
LP-PPA-wagungs-kali-linux2/raring

Click on the repositories and install the Tools from the list.


you can read the keystrokes by the read command for this use the following bash script

#! /bin/bash
read -s -n 1 key # -s: do not echo input character. -n 1: read only 1 character (separate with space)
if [[ "$key" == "your key" ]];then
    #your script here
fi

you can experiment with the read command and some bash scripts


I found a solution based on socat in this post:

https://superuser.com/a/536295/621970

so, this does the trick:

sudo socat TCP-LISTEN:2221,su=nobody,fork,reuseaddr TCP-CONNECT:192.168.2.100:2222

It connects Port 2221 on the local host to port 2222 on the remote machine 192.168.2.100

sudo needed to su to nobody.

The fork option means that it will renegotiate the incoming port, so that it doesn't block.


Some windows looks weird (no theme applied?)

Clementine and VLC are Qt applications, and Numix is a GTK theme, so you need to tell Qt applications to use GTK themes. This can be done by installing 'qt4-qtconfig'.

sudo apt-get install qt4-qtconfig

Then find the application in your menu called "Qt 4 Settings" and run it.

In "Qt 4 Settings" where it says "GUI Style - Select GUI Style:", choose "GTK+" in the dropdown menu. Then click on File in the menu, and then Save.

VLC and Clementine should now be themed properly. You Might need to restart those applications for the theme changes to take effect.


How can I check battery percentage in Razer Mamba Wireless 2018 in command line?

There are probably several ways.  One is to use the command

inxi -B

You will probably need to sudo apt instal inxi first.


Found the answer by myself.

nautilus sftp://USER@SERVER/PATH will open a Nautilus window on the path I need.


In order to make this work, you need to understand the order and when each config file for shell is being sourced( aka loaded). ~/.profile is sourced at the time of logging in. It will be shown in TTY console perfectly fine - I personally have a message like that in my ~/.profile for when I go into TTY specifically. If you call a shell again from that session, it won't be sourced. Same thing in GUI. You log-in , the file is sourced only once.

My guess is that you are trying to show the message in the GUI terminal. When you log in into desktop your ~/.profile is already sourced, which also means it will not be sourced again in any terminal under that session, and message won't be shown. There's your problem.

The solution would be to place that message at the end of ~/.bashrc. That file is sourced when each interactive session is open, regardless of whether you are logging-in or not.


How do I get a list of only the files (not the directories) from a package?

It should be possible with xargs plus a shell test, for example

dpkg -L elixir | xargs sh -c 'for f; do [ -d "$f" ] || echo "$f"; done'


MySQL (InnoDB) shutsdown same time every day

I suggest that you need to check the below provided in your server.

Whether any cron is running in the server. You can make use of cron job log file to verify that. The log file is at the path : /var/log/syslog
Checking the load average at that specific time will also help you if there is any other load consuming process was initiated at that time. You can check the syslog at the location /var/log to trace it out.
Try reducing your key_buffer_size to 1MB and watch if it is still getting crashed.
If still getting crashed upgrading RAM should be the final option.
I also recommend that you run a mysqltuner script and let me know the output.


I did [chown -r root /usr/share/applications] when i just intended to only chown

/usr/share/applications

The permissions for -all- files in there is:

-rw-r--r-- 1 root root

So ...

chown root:root /usr/share/applications/
chmod 644 /usr/share/applications/

will restore it to default (I added both command just in case someone else ends up here looking for it but all you need is the chmod).

There are no directories in /usr/share/applications/ so the -r did nothing in your case.


Can't sync with Ubuntu One through a proxy server

Sadly, the current version doesn't have proxy support. It is the first item in our task list, though!

So, we are working on it, and you can keep yourself posted about it by following this bug in launchpad: https://bugs.launchpad.net/ubuntuone-client/+bug/387308


If your hardware arch is 64bit, I would go with 64bit guest OS. This will allow the guest of taking advantage of the 64bit arch where it can - source.

There could come a time where you would like to migrate the guest to a host with more ram. Staying with 64bit OS, will allow that to be an easier migration.

You have mentioned that you are looking for speed. You are running a guest on a host. Why not install both the 32 and 64 version and test them both out under a load. This is will give you more of a real world experience.

Some apps that are 32bit do not run well on 64bit arch, regardless if the OS is 32bit or not.


You can use rename for that:

rename -n 's/(.*)\/.*\./$1\/$1./' */*

This command needs to be started in the directory directly above the directories you want to process, exactly like in your example. It will first only list the changes for you to check, if you're happy with the results run it without -n to perform the renaming.

If there are multiple files with the same extension in one directory, rename will print a warning for every file and just leave them out. You could force overwriting with -f, but I highly doubt that's what you want to be done in these (rare?) cases.

Example run

$ tree
.
├── This.Is.A.Crazy.Name.S00E00.720p
│   ├── asdfasdfasdfasdfasdfasdfafs.mkv
│   ├── info.nfo
│   └── proof.jpg
└── You.See.Where.This.Is.Going.14x01.480p.crappo
    └── video.mp4
$ rename 's/(.*)\/.*\./$1\/$1./' */*
$ tree
.
├── This.Is.A.Crazy.Name.S00E00.720p
│   ├── This.Is.A.Crazy.Name.S00E00.720p.jpg
│   ├── This.Is.A.Crazy.Name.S00E00.720p.mkv
│   └── This.Is.A.Crazy.Name.S00E00.720p.nfo
└── You.See.Where.This.Is.Going.14x01.480p.crappo
    └── You.See.Where.This.Is.Going.14x01.480p.crappo.mp4

Explanation

rename 's/(.*)\/.*\./$1\/$1./' */*

s/a/b/ – substitute a by b
(.*)\/.*\. – take everything until (excl.) the last slash saving it as group 1 and take the slash and everything until (incl.) the last dot
and substitute it by
$1\/$1. – group 1 (dir name), a slash, group 1 again (file name) and a dot (dot before extension, which itself didn't get touched)


Thank you paru38.

Using sudo apt-get remove mint-meta-mate removed most of linux mint.

However, I then used sudo apt-get autoremove mint-meta-mate to completely remove linux mint.


To solve your problem :

Download amd64.tar.x from this Link

Save it on a path and remember this path .

Now open cmd and add this command :

wubi.exe --dimagepath=(path of the file example d:\name.amd64.tar.x)

Now it will extract it instead of downloading it .

This is image file for Ubuntu . size approx 500MB


Get it!

Libcupsys2 can be depackaged using dpkg-deb -x and in control

http://security.ubuntu.com/ubuntu/pool/main/c/cupsys/libcupsys2_1.3.7-1ubuntu3.16_i386.deb
Here it is. So, if you also have libkrb5-3 instead of libkrb53 needed in dependencies you do the following:
dpkg-deb -x libcupsys2_1.3.7-1ubuntu3.16_i386.deb common
dpkg-deb --control libcupsys2_1.3.7-1ubuntu3.16_i386.deb
cd DEBIAN
nano control

You need to replace libkrb53 with libkrb5-3
save and exit
cd..
cp -r DEBIAN/ common/

dpkg -b common libcupsys2_1.3.7-1ubuntu3.16_i386.deb

That's all!


There is a fork of Owncloud called Nextcloud, and it is the version that is better supported. I recommend to use Nextcloud instead.

In Ubuntu 16.04 you can install Nextcloud as a snap (the new type of installation packages for Ubuntu 16.04 or newer).

The full documentation on how to try the snap edition of Nextcloud can be found at
https://github.com/nextcloud/nextcloud-snap


How to recover/reset forgotten Gnome Keyring Password?

Resetting everything (delete all passwords and start new keyring):
rm ~/.local/share/keyrings/login.keyring

Then, log out and log back in. Ubuntu will automatically create a new login.keyring for you.
Or
Navigate to Places > Home.  Press Ctrl + H to view "hidden files".  Navigate to .local > share > keyrings and delete login.keyring
Using the same keyring (resetting keyring password but keeping old passwords in keyring):

Make a backup of the keyring
 cd ~/.local/share/keyrings/
 cp login.keyring login.keyring.backup

and after that delete login.keyring file
    rm ~/.local/share/keyrings/login.keyring

Create a new keyring file from Gnome Keyring with the name login

Replace the new keyring file with the backup of the old keyring file
 cd ~/.local/share/keyrings/
 mv login.keyring.backup login.keyring

Note: before Ubuntu 12.10 the path to the keyrings folder was ~/.gnome2/keyrings/ instead of ~/.local/share/keyrings/.


Solved it. Went to privacy settings and turned of network verification


Creating a mount point if it does not exist

try this:

if you want to create a Mount Point called DISK1, then type the following command in the terminal :

sudo mkdir /media/DISK1


What's the unity equivalent of gnome's ALT-F2?


How do I launch my script from a launcher?

I do not know what exactly is "content that I believe is appropriate". However, if you can run the script through terminal all you have to do is create a script with:

#!/bin/bash
cd /path/to/folder
command-you-would-run-in-terminal

Make the script executable. Then in your .desktop file, launch the script instead of your command directly.

Example

#!/usr/bin/env xdg-open

[Desktop Entry]
Version=1.0
Encoding=UTF-8
Type=Application
Terminal=false
Exec=path/to/icon/bash script
Name=Script name
path/to/icon/here
Comment=A description here


"apt-get --print-uris" to list URI for downloading extra functionality package for amarok,reqonk

Thank you guys for your answers.
I think i have found a way to list the http's for downloading codecs. It is not that efficient though. I happen to notice that "qapt-batch" tries to install these package. First I open the notification

Then I click install selected. Then I can see the Packages

it would have been very useful for me if I could copy the package names with my mouse so that i could apply apt-get --print -uris install packagename_s
But i cannot copy the package names. So after giving authentication i opened /var/log/auth.log
and there i could see the last command authentication qapt-batch --install packagename_s
I copied them from there. Then I extracted http's using --print-uris.


Ubuntu 15.04 installed on USB drive but does not boot-up

I finally ended up solving my problem, so let me sum up the lessons learned.

I have a Windows-10 PC with UEFI. In that case make sure the Linux installation disk also needs to support UEFI. (check the link for more info )
I had the Linux installation image also with UEFI, but I had activated the compatibility/leagacy BIOS mode on my PC. This was one reason why the image did not work. I rebooted my PC by activating UEFI mode and re-installed Ubuntu, that worked.


How to create an .img file from .iso on Ubuntu?

I would take a stab in the dark, but you are trying to make an img file from an iso, right? If that's the case then there isn't any difference between iso's and img's apart the extension:

  There is no difference in the structure of ISO and IMG formats if the IMG file is uncompressed. It is possible for an IMG format file to be renamed with the ISO file extension and then opened in software that only recognizes the ISO file format. This is an effective way of accessing disc information in programs that do not handle the IMG format.

(source)

Wikipedia also seems to agree:

  ISO images are another type of optical disc image files, which commonly use the .iso file extension, but sometimes use the .img file extension as well. They are similar to the raw optical disc images, but contain only one track with computer data obtained from an optical disc. They can not contain multiple tracks, nor audio or video tracks. They also do not contain the control headers and error correction fields of CD-ROM or DVD sectors that raw disc images usually store. Their internal format follows the structure of an optical disc file system, commonly ISO 9660 (for CDs) or UDF (for DVDs). The CUE/BIN and CCD/IMG formats, which usually contain raw disc images, can also store ISO images instead.

So, how to convert an iso to img? Just change the extension:

rename 's/\.iso(?=[^.iso]*$)/.img/g' *

Now, to create an img, you should use dd and save it into a file called img.


What do I do with this tar.gz file from Broadcom for my Dell 1510 wireless card?

Try to install broadcom drivers from Additional Drivers app - it will install the same driver that you want to install manually


System boot order not found after installing Ubuntu 20.04

You can select which system to boot with the help of boot-repair. Installed 20.04 yesterday and had the same problem. Can you open the boot menu in BIOS?


Ubuntu 16.04 some applications take too long to start up

I got the same problem out of the blue on my new notebook. After that I did a new ubuntu installation on a desktop machine, and the problem didn't happened there.

After some research, I found the solution here on the Arch Linux Forums

Close all your apps (like Chrome) and try running the following command on a terminal:

gnome-keyring-daemon &

After that, open Chrome again. It might ask for your account password again once. For me this solves the delay problem. Chrome and gnome-terminal are opening very fast now (< 1 sec delay instead 30 sec delay).

For you knowledge, Chrome was throwing the following error before this fix:

  Gkr-Message: secret service operation failed: Did not receive a reply.
  Possible causes include: the remote application did not send a reply, the message bus security policy blocked the reply, the reply timeout expired, or the network connection was broken.

I logged Chrome startup with strace, and this message alone took 25 seconds to appear. I guess this is a system message, not only for Chrome, because I was having the same issue with gnome-terminal starting up as well, and this fix solve that issue too.


How to setup a Wireless Access-Point using my laptop's WiFi card?

Not all wireless cards support Access Point mode. Check to make sure your card does, before you frustrate yourself in software.


Location of Tcl 8.6 library and Location of Tk 8.6 library: not found

Problem solved by using the latest package scid_vs_pc-4.17 instead of scid_vs_pc-4.9


If you can't find it maybe you've done a clean install and haven't done an update yet, so do the following:

sudo apt-get update

sudo apt-get install [application]

If that doesn't work update your question with what happens. Also specify what package you are trying to install.


Dual booting windows 8.1 and ubuntu, windows automatically loads

You could try installing GRUB, or enabling it, if it's installed:

Boot the machine using a Live CD.
Open a terminal.
Find out the name of the internal disk by using fdisk to look up the device's size.
For example:

sudo fdisk -l

Install GRUB boot loader onto the proper disk (the example below assumes it is /dev/sda):

grub-install --recheck --no-floppy --root-directory=/ /dev/sda

Source

NOTE: you might need to install GRUB... A good guide is this answer.


Where can I configure iwconfig wlan0 power on/off?

Is it a USB-dongle? If yes, this may help:

echo 'KERNEL=="wlan*", ACTION=="add", RUN+="/sbin/iwconfig wlan0 power off"' | sudo tee /etc/udev/rules.d/10-wlan-stick.rules

Alternatively, there is a script:

wget http://media.cdn.ubuntu-de.org/forum/attachments/38/32/4675487-power_d_skripte.tar.gz
sudo tar xvf 4675487-power_d_skripte.tar.gz -C /etc/pm/power.d

From here:
https://forum.ubuntuusers.de/topic/sendeleistung-der-wlan-antenne-einstellbar/#post-4675487


Gimp crashes Ubuntu 12.04 when using tool

A bug has been filed for your problem: https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/1021517

(I guess you can close this question by saying that this is the correct answer.)


To run a shell script you first give it permissions:

chmod u+x nameofthescript

Then you run it. Assuming you're in the directory where the script is:

./nameofthescript

If it needs to run with root privileges:

sudo ./nameofthescript


Brightness problem in Ubuntu 12.04 Precise Pangolin

This solution worked for me:

gksu gedit /etc/default/grub
find the line starting with

GRUB_CMDLINE_LINUX_DEFAULT

add "acpi_osi=Linux acpi_backlight=vendor" to the options, for example:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=Linux acpi_backlight=vendor"

run sudo update-grub2
reboot


Did you try:
https://tutorialforlinux.com/tag/mysql-workbench-install-ubuntu/
Also:
Mysql WorkBench not supporting with Ubuntu 20.04 LTS


If you have created a user with login Yona whereas it previously was yona, then you can correct this by opening a terminal and typing:

sudo usermod -l yona Yona

If yona logs in and doesn't get to her files, then you can subsequently set the correct home directory using:

sudo usermod -d /home/yona yona

To solve the issue with the password, open a terminal and type

sudo passwd yona

and you can set yona's password without the system complaining. Note that this may first ask for your password, then twice for Yona's new password, like this:

ilan@machine:~$ sudo passwd yona
[sudo] password for ilan:              # here enter your password
Enter new UNIX password:               # here enter her new password
Retype new UNIX password:              # here enter her new password again

If the files in Yona's home directory all seem to have a strange numeric owner, you'll need to change Yona's uid a/o gid to what it was on the old system, thusly:

sudo usermod --uid ### --gid ### yona

where you substitute the appropriate numbers at the ###.

Next time when restoring the system, I would recommend creating Yona's account not via the GUI, but using the adduser command, substituting the appropriate values:

adduser --home /home/yona --uid ### --gid ### yona


Local Drives showing under Other Locations in Ubuntu 18.04

You cant write to your Windows disks because Windows has an hybrid shutdown

You must shut down Windows completely
Under windows Hold the Shift key while clicking on the shutdown button

You may also disable the 'Fast Startup' feature of Windows


Ubuntu uses an installation system based off of Debian, which is to use .deb packages.  These packages contain instructions for installing and removing software from the system.

This system is controlled via apt, apt-get, aptitude, or the Synaptic Package Manager GUI (a front-end for apt-get and dpkg).  Installation is as simple as specifying what package(s) to install, and removal is similar.

There is also a Software center in Ubuntu.  This software center is for the less-tech-savvy user, but has the same results as my aforementioned methods for managing packages.  With the Software Center, too, you don't need to know all the package names, you only need to know the software's name, and it can usually find it (if its in the repositories).


AMD System fresh install , Only USB 3 working (IOMMU?)

I was getting errors on a fresh install of Ubuntu 16.04 on my PC

CPU: FX 6300
MOBO: GA 970A-DS3P

Errors were like this:

usb 5-1: device descriptor read/64, error -32
usb 5-1: device descriptor read/64, error -110
usb 5-1: device not accepting address 4, error -32
usb 5-1: device not accepting address 4, error -110

Then I tried this.

First, enable IOMMU in the BIOS by restarting your computer and pressing delete to enter the BIOS (3.0 ports won't work after this step, don't worry, they will soon)

Plug your USB mouse and keyboard in USB 2.0 ports.

Save and exit the BIOS

Then In Ubuntu:

Press Ctrl+Alt+T to open up a terminal

Run the following command:

sudo nano /etc/default/grub

Only edit the empty quotes in this line to read: GRUB_CMDLINE_LINUX="iommu=soft"

Save changes to grub and exit

Open up a new terminal with Ctrl+Alt+T,

Run the following command: sudo update-grub

Exit the terminal

Restart your computer, press delete to get back into the BIOS

Disable IOMMU, load optimized defaults and restart.

It's done!

USB 2.0 and USB 3.0 should work now in Ubuntu, and disabling IOMMU in BIOS may also help speed up your boot.


How to Enable or Show Ubuntu or Mac style Dock Bar in Ubuntu?

I'd recommend CairoDock for Ubuntu (https://help.ubuntu.com/community/CairoDock). I haven't used it yet, but it seems to be very popular (and customizable). Let me know if this solves your question.


Can I safely reinstall PCManFM in Lubuntu desktop?

As you said you want to remove and eventually reinstall (if I correctly understand your question) I would say, it is okay to do so.

Also note, lubuntu-desktop, lubuntu-core are metapackge which actually doesn't install anything (those packages are used to pull other packages) and lubuntu-default-settings is used to set the default settings of Lubuntu, such as default background, theme, icon-theme, keyboard shortcuts and others.

You said, when you wanted to remove pcmanfm, synaptic said, it will also remove lubuntu-desktop, lubuntu-core, lubuntu-default-settings, lxde and lxde-core. This is normal since package pcmanfm is a dependency (you may say required package) for those packages and when you tried to remove it, there is no reason to keep those packages. (Because those packages wouldn't install without pcmanfm).

If you really wanted to reinstall pcmanfm and you have another DE such as Xfce or KDE or Unity (GNOME), I recommend you to switch to that DE and run this command in a terminal to remove and reinstall the packages.

sudo apt-get --purge remove pcmanfm

This will remove pcmanfm, those other five packages with all of their configuration files. Now use this command to reinstall everything

sudo apt-get install lubuntu-desktop lubuntu-default-settings lxde

Note that this command did not explicitly say to install pcmanfm but that package will be installed as a dependency package of lubuntu-core which will itself be installed as a dependency of lubuntu-desktop.

If you don't have other DE installed, just switch to one of the virtual console by pressing Ctrl+Alt+F1 and execute the commands.  To return to the graphical session, press Ctrl+Alt+F7  .

This should help you to reinstall pcmanfm.


How to upgrade Ubuntu in multiple sessions?

I think that the most advisable in your case is simply downloading the ISO image and do an in-place upgrade instead of going thru the whole upgrade path. This way you can control how much data you use per day and upgrade at any time.

Remember to do backups.


Share my VPN connection with other LAN users

fugitive's answer works, even on Ubuntu 19.04 but if you don't need to host an internet connection for your other LAN devices, then you can skip a few steps.

If all devices are connected to your LAN via wifi or wired, you can just use these steps:

Confirm that your PC with the VPN connection can forward packets like a router

cat /proc/sys/net/ipv4/ip_forward ##this should return '1', if it doesn't
do step 2
echo '1' >> /proc/sys/net/ipv4/ip_forward

or you can use sysctl.conf

echo "net.ipv4.ip_forward=1" >> /etc/sysctl.conf && sysctl -p #persistent mode

then set iptables to NAT and forward packets received on your local LAN interface and sent out of your tun interface (VPN)

iptables -t nat -A POSTROUTING -o tun+ -j MASQUERADE

iptables -A FORWARD -i wlan+ -o tun+ -j ACCEPT #change wlan+ to match your LAN adapter
iptables -A FORWARD -o tun+ -j ACCEPT
iptables -A FORWARD -i tun+ -m conntrack --ctstate ESTABLISHED,RELATED   -j ACCEPT
iptables -A INPUT -i tun+ -j ACCEPT

Finally, on your other LAN computer that you want to use your shared VPN -
  1. use the route command to add a route for the VPN'd subnets and set the
     gateway to the IP of your LAN computer network adapter that you set in
     iptables (not tun, but the wlan+ or en+ adapter)

example:
if the computer with the VPN connection has an en0 adapter on your local network with an ip of 192.168.0.100, and your VPN accessible network subnet is 10.0.0.0/24

On your other LAN computer without the VPN connection you'd enter a route cmd like --(for Windows OS)

route add 10.0.0.0 mask 255.0.0.0 192.168.0.100 metric 200 if <interface>


Nvidia 361.42 and LightDM problem on xubuntu

assuming you have done a "fresh install" of xubuntu 16.04 and not knowing the model of the machine and neither the video card i would do:

sudo apt-get remove --purge nvidia* && sudo apt-get install nvidia-settings.

Then running nvidia-settings i would figure out what my needs are and make the settings permanent.


Terminal problem after updating python to 3.7

If you followed the upgrade path from the linked question, all you did is make the symlink /usr/bin/python3 point to python 3.7 instead of python 3.6.

The line you changed is called a "shebang" line. It tells the kernel which application to use to interpret the file.

Applications from Ubuntu repositories expect /usr/bin/python3 to be python 3.6 and may be incompatible with python 3.7.

So apparently, gnome-terminal is incompatible with 3.7 and if you change the shebang to explicitly point to 3.6 it works again.

You are not supposed to change the default python version, which is evident in the fact that it is not installed in debian alternatives by default. I'd recommend changing it back to 3.6 because there are probably a lot of other applications that won't work.

Instead of changing /usr/bin/python3, use /usr/bin/python3.7 on the command line or in shebang lines of your own python modules.


Open-source driver for AMD Radeon HD 6490M

Have you tried this?

sudo apt-get remove --purge xorg-driver-fglrx fglrx*
sudo apt-get install --reinstall libgl1-mesa-glx libgl1-mesa-dri fglrx-modaliases
sudo dpkg-reconfigure xserver-xorg

sudo apt-get install --reinstall xserver-xorg-core

This should make your system use the opensource driver. It worked for me. I have a different computer but it has a Radeon HD 4000 series


BASH Script to run a command only if a host is alive

Probably something like this:
if fping -q $MYHOST; then
  do my command
fi

Alternatively, this may make sense
if ! fping -q $MYHOST; then
  # exit on error
  echo "host $MYHOST is not alive"
  exit 1
fi
do more commands
bla bla bla


How to mount external drive directly under "/media/" and not under "/media/username/"?

You need to modify your /etc/fstab file specifying the mount point you wish.

Open a terminal and type sudo blkid. Identify the partition and copy its UUID.

Then gksudo gedit /etc/fstab

Add a line like this:

UUID=your-UUID-here /media/EXT4               ext4    errors=remount-ro 0       1

Reboot or run sudo mount -a and you're done.


Ubuntu wants to install on USB rather than hard drive

Ubuntu wasn't recognizing my hard drive. To fix this, I entered the BIOS and switched the SATA mode from RAID into AHCI. After that, my installation worked perfectly.


I'm pretty sure the problem is you've added an incompatible source or text was added to your /ect/apt/sources.list.d/ directory. It's causing problems updating your software repo cache. Remove the added file/sources, then you should be able to update (apt-get update) normally.

The error sounds like there's some type of HTML on line 1 of /etc/apt/sources.list.d/playonlinux.list that got in there somehow; that shouldn't be there. If you know what lines or sources were added, you can use any text editor to edit the source files (sudo nano /etc/apt/sources.list.d/playonlinux.list for example), or a file browser to remove the whole file if it doesn't belong there.

This apt-get command should help, "it updates the package cache and checks for broken dependencies." and might reproduce your error message:

sudo apt-get check

When I added some junk to my sources.list, it gave me this helpful info, pointing to the file & line that had the first error (after fixing run it again in case there's more errors):

$ sudo apt-get check
Reading package lists... Error!
E: Type '<bd' is not known on line 4 in source list /etc/apt/sources.list
E: The list of sources could not be read.
E: The package lists or status file could not be parsed or opened.

Or you can use GUI tools to manage them (may not work if they're corrupted with HTML now) see this link for help https://help.ubuntu.com/community/Repositories/Ubuntu

Or this link for help using command line / terminal tools https://help.ubuntu.com/community/Repositories/CommandLine

Be very careful with your software sources, I'd make a backup copy of everything in /ect/apt/sources.list and /ect/apt/sources.list.d/ first, just in case. Not knowing what your Ubuntu version is I'm not sure what the "defaults" should be, or whether you've added extra PPA's or other sources.

Backup the sources.list files

Just copy them to a backup folder somewhere, in your home folder, or this should work:

sudo cp /etc/apt/sources.list /etc/apt/sources.list.old
sudo cp -R /etc/apt/sources.list.d /etc/apt/sources.list.d.old

Restoring the default Ubuntu sources.list

For Ubuntu, if you do this it should generate a new fresh sources.list file

delete the old files (sudo rm /etc/apt/sources.list and sudo rm -R /etc/apt/sources.list.d but BACKUP FIRST).
Then do either of:

Run the Software Sources (from the programs menu / dash, or sudo software-properties-gtk or sudo software-sources) select/check-mark some repos, pick a server and update.
OR Generate a new one at http://repogen.simplylinux.ch/ using your version & country (to pick local mirrors), then copy & paste it into your new sources.list with
gksudo gedit /etc/apt/sources.list
or in a terminal  with
sudo nano /etc/apt/sources.list

The site http://repogen.simplylinux.ch/ has a LOT of optional PPA's too, looks quite useful.  [courtesy How do I restore the default repositories? ]


Here is the documentation Plymouth.

It is just the animation/loading screen from the beggining of ubuntu boot.


This is one idea:

Define a compose key. You do that in System Settings -> Keyboard -> Shortcuts -> Typing.
Create the file ~/.XCompose with this contents:

include "%L"
<Multi_key> <U007E> <U007E> : "⁓" U2053 # SWUNG DASH

That way (at next login) typing <Compose> + ~ + ~ will result in ⁓.

Not exactly what you asked for, but maybe you still want to consider it.


Ubuntu asks for password several time when logging in

That sounds like a problem with the Gnome keyring. I suggest backing up your ~/.gnome2/keyrings directory and then try removing it to see if that helps. Of course, when you reenter your passwords for Evolution or a wireless network, it will ask you to create a password for your newly created keyring (picture shown below). Make sure that password is the same as your login password.

Also, if you connect to a wireless network and you log in automatically, make sure you select "Available to all users" in your wireless settings.


Do not change the directory and you do (/should) not need to change the directory itself. /etc/openvpn needs to be something like 775 (rwxrwxr-x).

The permisions 400 (=readonly) are for the cert files. This explains it: How do I setup OpenVPN so I can securely use the internet from an unsecured hotspot?

And do not forget: changes to /etc/ need sudo.


Ubuntu 16.04 has a lot of problem with video driver with Linux kernel 4.4.0. I suggest you to install Linux kernel 4.6.0 with this guide. In my case my nVidia started to work much better


Does upgrading apache via apt-get install wipe source/config files?

Never. Configuration files are only created when those do not exist. Otherwise those are left as is. Would break usage if those are deleted or changed back to default. If someone needs to update a configuration file editing is done by creating commands to alter the configursation. sed is a popular tool for this. Example:

echo "hello" | sed 's/hello/bye/g'
bye

Only the "purge" option will delete configuration files.

Even if there are incompatibility issues in configurations you will get warnings for a long period (as in "{option} is deprecated; please use {new option}. Apache and MySQL had a couple of those in the past 10, 15 years.

  Additionally, will I need to restart the server after updating?

No. Only kernel updates need a reboot and even those you can postpone.

You will want to restart the apache service if that is not done by itself. If only just to check if all still works as intended.

  wipe source files

What source files? The files related to apache will be overwritten by their new versions when there are new versions. If you mean the installed files when installing apache from source: that version will not be overwritten by apache. Installing from source is something you do in /opt/  so not at the locations apt installs.


Adding to @thomasrutter answer:

Just in case someone doesn't know this (i didn't for sometime), after running this command to reconfigure phpmyadmin

sudo dpkg-reconfigure -plow phpmyadmin

this screen will appear in your terminal, make sure the * is there inside the brackets [] like this [*] for apache using the Space


How do I make my synclient settings stick?

You need to put the settings in a xorg.conf file as follows:

sudo gedit /usr/share/X11/xorg.conf.d/60-synaptics-options.conf

In the new file, type

Section "InputClass"
  Identifier "touchpad catchall"
  Driver "synaptics"
  MatchIsTouchpad "on"
  MatchDevicePath "/dev/input/event*"

  Option "RTCornerButton" "0"

EndSection


Ubuntu 18.04: Change color of window title bar

This works for me (Ubuntu 18.04 + Gnome 3.28.1):

nano ~/.config/gtk-3.0/gtk.css

To customize the active title bar background colors use .titlebar and .backdrop (for inactive windows).

.titlebar {
    background: #3089FF;
    color:white;
}

.titlebar:backdrop  {
    background: #777777;
    color:white;
}

After saving the file, remember refresh gnome using this command:

setsid gnome-shell --replace


How to access personal ubuntu computer remotely

For remote access to PC I propose ssh. Secure shell crypt traffic, also you can with option  -X from client start, on client, app from server.

Detailed manual have on link here.

If you access ubuntu from win you can use putty.


Ubuntu 12.04 booting into busybox after update

Fixed it, using boot-repair, I added the kernel option rootdelay=90. Now the linux-kernel-3.5.0-34-generic-image. But after much research and testing, I have decided to go with the linux-generic image boots properly. which is kernel version 3.2.0-48. It's the only one that boots up correctly without having to add any kernel options. Also using this kernel solved another issue I had, which was a waking up took too long. Now waking up after suspend takes just 2 seconds as opposed to 10-20 seconds using the other images.


Simply open PlayOnLinux and either:

double-click on the office applications shortcut
or mark the created shortcut, then hit 'Run', to open it.

If you haven't already created a shortcut of 'Word', 'PowerPoint', 'Excel' etc.. you ought to do so, the repeat step 1 or 2 from above.

Also, you can directly open the application of choice .exe, by browsing into its dir /home/USERNAME/.PlayOnLinux/wineprefix/USERAPP and 'right click'-> 'open with..'


It's the panel height that makes the difference.  That can be controlled from Panel Options (right click on the K).


Is there any way to 'hook' the messaging menu?

Interesting question.  There is no official API for discovering if the messaging menu has changed it's state.  You can do it by looking at the DBus interface of the indicator-messages-service.  A shell script way is like this:

  $ gdbus call --session --dest com.canonical.indicator.messages --object-path /com/canonical/indicator/messages/service --method com.canonical.indicator.messages.service.AttentionRequested

There is also a signal "AttentionChanged".  You can track that to determine the state as it updates.

Also, if you're interested in the individual items in the messaging menu all their information is exported using libindicate.  It is possible to have another libindicate listener on DBus that gets all of the information and aggregates it in a different way.


In your pastebin, we see this:

[/etc/modprobe.d/rtl8723de.conf]
options rtl8723de ant_sel=1

You haven’t any rtl8723de device; yours is an rtl8723be. They are two different devices. Let’s remove the needless file:

sudo rm /etc/modprobe.d/rtl8723de.conf

We also see this:

[/etc/modprobe.d/rtl8723be.conf]
options rtl8723be ant_sel=2
options rtl8723be 11n_disable=1

11n_disable is not an available parameter in the driver rtl8723be. Confirm:

modinfo rtl8723be

Let’s remove the needless declaration:

sudo nano /etc/modprobe.d/rtl8723be.conf

Remove the 11n line so that the file now only contains:

options rtl8723be ant_sel=2

Save (Ctrl+o followed by Enter) and close (Ctrl+x) the text editor.

We also see:

Cell 01 - Address: <MAC '301 Th' [AC1]>
                    Channel:9
                    Frequency:2.452 GHz (Channel 9)
                    Quality=54/70  Signal level=-56 dBm
                    Encryption key:on
                    ESSID:"301 Th"
                    Bit Rates:1 Mb/s; 2 Mb/s; 5.5 Mb/s; 11 Mb/s; 6 Mb/s
                              9 Mb/s; 12 Mb/s; 18 Mb/s
                    Bit Rates:24 Mb/s; 36 Mb/s; 48 Mb/s; 54 Mb/s
                    Mode:Master
                    Extra:tsf=00000000c8e6d93d
                    Extra: Last beacon: 60ms ago
                    IE: WPA Version 1
                        Group Cipher : CCMP
                        Pairwise Ciphers (1) : CCMP
                        Authentication Suites (1) : PSK
                    IE: IEEE 802.11i/WPA2 Version 1
                        Group Cipher : CCMP
                        Pairwise Ciphers (1) : CCMP
                        Authentication Suites (1) : PSK

I have worked on several cases where removing a space in the name of the SSID improved connectivity. If this is a router for which you have administrative privileges, I suhhest that you rename it to 301Th or 301_Th or some such without a space.

Next, check the settings in the router. WPA2-AES is preferred; not any WPA and WPA2 mixed mode and certainly not TKIP. Second, if your router is capable of N speeds, you may have better connectivity with a channel width of 20 MHz in the 2.4 GHz band instead of automatic 20/40 MHz, although it is likely to affect N speeds. I also have better luck with a fixed channel, either 1, 6 or 11, rather than automatic channel selection. Also, be certain the router is not set to use N speeds only; auto B, G and N is preferred. After making these changes, reboot the router.

Please see this interesting post about the unreliability of auto channel select: https://superuser.com/questions/1311149/why-do-wifi-routers-do-such-a-bad-job-of-channel-selection

Next, I recommend that your regulatory domain be set explicitly. Check yours:

sudo iw reg get

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

sudo iw reg set IS

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

sudo nano /etc/default/crda

Change the last line to read:

REGDOMAIN=IS

Proofread carefully, save and close the text editor.


Trusty partman preseed is ignoring partition sizes

The final partition will use the whole free size of the disk. you can add an unmounted, unneeded  partition here at the end and remove it later.

Source: https://unix.stackexchange.com/questions/179880/preseed-setting-wrong-partition-size


Difference between 64 bit.rpm and 64 bit.deb packages

Summary:
If you use Ubuntu, always go for .deb packages!
They can be installed with the terminal command below:
sudo dpkg -i /PATH/TO/PACKAGE-FILE.deb

Or by simply double-clicking on them in your Files Manager, which opens them in the Software Center application.
Explanation:
There is a set of "basic Linux distributions" on which most others are based on. Two of the most important ones are probably Debian and Red Hat.
Ubuntu and all of its derivates are based on Debian.
Now those two Linux distributions have different software packaging systems:

Debian uses .deb packages (simply derived from the first 3 letters of "Debian")
Red Hat uses .rpm packages (Red Hat Package Manager)

Those two packaging systems have some differences and are not compatible, that means you can't natively install RPM packages on a Debian-based system like Ubuntu.
However, in some cases you will be able to convert packages from one systems into another using the command-line tool alien.


Distribute own application on PPA or use own server with repository?

I'll address the three parts of your question:

I think it's matter of opinion. As a user, I don't have any preferences for either of those. As a developer, I mainly use PPAs for the reasons below.
The more obvious are that you use Canonical's resources instead of your own, and that includes the GPG key management, for your users. Remember that when one adds a PPA using the ppa:you/yourpackage shortcut, everything is taken care of. Contrast this to the scenario where you have to instruct the user on getting your gpg key, adding it to APT, etc. Additionally it builds packages for several Ubuntu releases, once the package is "buildable".
Packages in a PPA are already crypto-signed. Launchpad will check out the source from wherever you deploy, build it and sign it with your PPA key. If you require more security (say, to prevent anyone from intercepting inside Launchpad), then you should use your own repository, and sign the package yourself. This is a rather 'tinfoil hat' scenario where you would prefer to manage your own repo, rather than trusting Launchpad. Also a matter of opinion like in 1.


why does Ubuntu on my hp pavilion laptop's battery is draining very fast?

Power Management is not very efficient in Ubuntu by default. To get maximum performance, it is recommended to use third-party softwares. One of the best and highly configurable available software amongst them is TLP.

To install TLP, type:

sudo add-apt-repository ppa:linrunner/tlp
sudo apt-get update
sudo apt-get install tlp

For more info visit the TLP website.


How can I automatically move trash from a disk to another?

When you 'delete' the file, it's being copied to the Trash directory.  That much is obvious, but what might not be obvious is that this is a very quick operation because the file stays on the same disk and same partition.

If you delete a file and move it to another disk, this will increase the time it takes to delete the file.

If deleted files are taking up too much disk space, you could always just actually delete the files.  Hold Shift when you delete the files to delete them, skipping the Trash.  You could also clean your Trash regularly with a tool such as autotrash via cron.

I don't want to discourage you from exploring and having your system do exactly what you want, but you can run into weird issues with moving files to different disks when you delete them and I think your problem would be best solved by properly cleaning your Trash.


How to add server to the list in Starcraft brood war (Ubuntu, Wine)

Starting regedit iswine regedit

In regedit I have a key called "battle.net gateways" in:
HKEY_CURRENT_USER\Software\Battle.net\Configuration

I hope that is of help.

Another place where you could start looking for the correct place in the registry is iCCup.com. ICCup is a ladder for broodwar that has its own ladder server (that has to be configured in the registry).

iCCup's guide to getting started

Good luck!


Try sudo apt-get purge nvidia replace nvidia by the driver you are using. It will use the free driver Nouveau.

That worked for me.


Terminal
Try sudo su and enter your password. This will allow you to start apps as root and do administrator tasks.

GUI
Start a program with gksu to give ir root privileges. Press Alt+F2 and write gksu <application name>


Ubuntu 13.04 boots as terminal. No graphics. Radeon HD 7550M

I found the solution here: http://www.linuxtechtips.com/2012/12/amd-radeon-hd-7670m-on-ubuntu-1204.html

It's not for the 7550M, but it more or less works good enough to use the graphic enviroment to actually install the proper drivers.


To select a theme, go to the Theme tab in Gnome tweak tool. Next to shell theme, you should see a button the says "None" with a folder icon. If you see a triangle with an exclamation point, it means that you have not installed the gnome-shell theme selector extension, which can be installed using the following commands in a terminal window:

sudo add-apt-repository ppa:ferramroberto/gnome3
sudo apt-get update
sudo apt-get install gnome-shell-extensions-common
sudo apt-get install gnome-shell-extensions-user-theme

Once the extension is installed, select the the .zip file for the theme that you want to install (Do NOT unpack it) by clicking on the "None" button in the Theme tab of gnome-tweak-tool. Then, select it from the list to the right of the "None" button.


Adding a dir to the PATH for my account everywhere

Append your directory to PATH in /home/<user name>/.bashrc and source .bashrc from /home/<user name>/.profile using

if [ -f ~/.bashrc ]; then
. ~/.bashrc
fi

This way your changes will be available to you only in both GNOME & KDE and also in bash.

Do not edit /etc/profile as it will make the changes for all users.


Canon LBP 6230DW won't print under Ubuntu 17.10

It is suggested that one edit the ppd file; /etc/cups/ppd/[yourprinter].ppd

and add the line

  *CN_PDL_ConvertUserPaper: "dummy"

where it says [yourprinter]

this means find the ppd file relevant to your printer; in the folder ppd that is inside /etc/cups/

so if one uses the text editor gedit, the command would be

gksudo gedit /etc/cups/ppd/[yourprinter].ppd

.... but please do insert the correct name for your ppd file

I understand canon are working on a revision of the driver; note this is the 1.4 driver from here http://support-asia.canon-asia.com/contents/ASIA/EN/0100595001.html that comes down as linux-UFRIILT-drv-v140_uken.tar.gz so it is UFRIILT-drv-v140


Change icon size in unity's application switcher (alt-tab)?

I don't think that's possible. However, you can install compiz-settings-manager and attempt to use another application switcher -- there are three or so options available. However, I did not see any that would allow small icons.


You have to manually download its package and get executable from it by
cd ~/Download
wget http://archive.ubuntu.com/ubuntu/pool/main/d/dpkg/dpkg_1.19.7ubuntu3_amd64.deb
ar x dpkg_1.19.7ubuntu3_amd64.deb
tar -xf data.tar.xz
sudo cp usr/bin/dpkg /usr/bin/dpkg

And then reinstall it for sure by sudo apt-get install --reinstall dpkg .


Font style changed suddenly - what's wrong?

Actually I hardly see any difference on these screens, however since fonts seem to be unchanged, I would check if anti-aliasing for fonts is still enabled. On the first screen u have the Use anti-aliasing: Option which is currently set to System Settings. Go there and just enable it permanently and set full hinting. It might help (don't forget to restart KDE session after that change )


Facing error in recursive function for deriving factorial of a number

Well, bash is not "C". There are so many errors here that probably you need to read a good tutorial on bash scripting. You mix variable name and value, local and global variables, positional arguments, command evaluation, arithmetic expression, logical expressions...

First of all one advice: when you do not know what it's happening, use #! /bin/bash -xv as the first line. That will print each line before executing, and all the variable substitutions. Is really invaluable as debugging tool.

Next, I add a working version of the script. Mind you, this is a fast and dirty edit, there are plenty of bash expert here that will do a thousand time better script here.

#!/bin/bash
#This script will do factorial of a give number
fact()      #Function to calculate factorial of the given number
{
    local a
    if  [[ $1 -eq 0 ]]
    then
        echo "1"
    elif [[ $1 -lt 0 ]]
    then
        echo "You can't take the factorial of a negative number"
    else
        a=$(fact $(($1 - 1)) )
        echo $(( $1 * $a ))
    fi
}
# main
echo "<<--------MENU----------->>"
echo "We will do a factorial"
echo "Enter the number"
read num
echo "You entred " $num

echo "The result is :" $(fact $num)

See:

[romano:~/tmp] % ./test.sh
<<--------MENU----------->>
We will do a factorial
Enter the number
4
You entred  4
The result is : 24

And now a little surprising one:

<<--------MENU----------->>
We will do a factorial
Enter the number
22
You entred  22
The result is : -1250660718674968576

...the analysis is left to the reader ;-)


Tor Browser (torbrowser-launcher) is available in the default Ubuntu repositories in Ubuntu 16.04 and later. torbrowser-launcher handles
downloading the most recent version of Tor Browser Bundle for you, in your language and for your architecture. After installing Tor Browser, it can be launched by searching for tor in the Dash and clicking the Tor Browser icon. The Tor Browser Launcher Settings app is also installed along with Tor Browser.

Unfortunately the Tor Browser developers change their signing key that is used to install Tor Browser at periodic intervals which makes the torbrowser-launcher package from the default Ubuntu repositories not work because it is not as up-to-date as the current version of Tor Browser.
These are the instructions from the official Tor Browser User Manual in case the Ubuntu torbrowser-launcher package hasn't updated the gpg key that is required to install Tor Browser. When I updated the Tor Browser Developers signing key I noticed that the key that I updated will expire in less than one year.

Navigate to the Tor Browser download page.

Download the GNU/Linux .tar.xz file

(Recommended) Verify the file's signature. The steps for verifying the file's signature are shown below.

When the download is complete, extract the archive with the command tar -xf [TB archive] or with the Archive Manager.

Navigate to the newly extracted Tor Browser directory. Right click on start-tor-browser.desktop, open Properties and change the permission to Allow executing file as program by clicking the checkbox. Double-click the icon to start up Tor Browser for the first time.

Alternatively, from inside the Tor Browser directory, you can also start from the command line by running:
 ./start-tor-browser

How to verify Tor Browser's signature
Fetching the Tor Developers key
The Tor Browser team signs Tor Browser releases. Import the Tor Browser Developers signing key (0xEF6E286DDA85EA2A4BA7DE684E2C6E8793298290):
gpg --auto-key-locate nodefault,wkd --locate-keys torbrowser@torproject.org

This should show you something like:
gpg: key 4E2C6E8793298290: public key "Tor Browser Developers (signing key) <torbrowser@torproject.org>" imported
gpg: Total number processed: 1
gpg:               imported: 1
pub   rsa4096 2014-12-15 [C] [expires: 2020-08-24]
      EF6E286DDA85EA2A4BA7DE684E2C6E8793298290
uid           [ unknown] Tor Browser Developers (signing key) <torbrowser@torproject.org>
sub   rsa4096 2018-05-26 [S] [expires: 2020-09-12]

After importing the key, you can save it to a file (identifying it by fingerprint here):
gpg --output ./tor.keyring --export 0xEF6E286DDA85EA2A4BA7DE684E2C6E8793298290

Verifying the signature
To verify the signature of the package you downloaded, you will need to download the corresponding ".asc" signature file as well as the installer file itself, and verify it with a command that asks GnuPG to verify the file that you downloaded.
The example below assumes that you downloaded these two files to your Downloads folder.
gpgv --keyring ./tor.keyring ~/Downloads/tor-browser-linux64-9.0_en-US.tar.xz{.asc,}

The result of the command should produce something like this:
gpgv: Signature made 07/08/19 04:03:49 Pacific Daylight Time
gpgv:                using RSA key EB774491D9FF06E2
gpgv: Good signature from "Tor Browser Developers (signing key) <torbrowser@torproject.org>"


persistent accidental icons on gnome (fallback) top panel

The Alt+rightclick combination did not work because I had set the leftAlt key to toggle between my keyboards (this I had done under keyboard layout options).

Having disabled that option, I was able to normally use the Alt+rightclick combination to remove the unwanted icons.


This was fairly simple. First you'll need ffmpeg installed.

Then there's this simple terminal command you can use to convert all the audio files to MP3:

for f in *.flac , *.m4a , *.ogg ; do ffmpeg -i "$f" -ab 320k "${f%.m4a}.mp3"; done

Breakdown:

for f in *.flac , *.m4a , *.ogg ;: For every audio file of these types,
do ffmpeg -i "$f" -ab 320k "${f%.flac}.mp3";: Convert that file to MP3, get the next file.
If you want to change the bitrate, simply change the 320k in kbps.
You can change the filetypes it looks for simply with that comma-separated list of *.flac , *.m4a , *.ogg to whatever files ffmpeg can decode.
You can change the output name to whatever you want, "${f%.m4a}.mp3" could be "${f%}.mp3" or "${f%.audio}.mp3", f% represents the original filename.


How to automatically execute a command in a terminal after a period without activity?

You can use the output of w in a cron job. See the row IDLE. This is the time since the last keystroke is made in the shell:

user@host:~# w
 20:29:12 up  4:04,  1 user,  load average: 0.00, 0.00, 0.00
USER     TTY      FROM              LOGIN@   IDLE   JCPU   PCPU WHAT
root     pts/0    1.2.3.4          18:24    0.00s  0.23s  0.00s w
user@host:~# sleep 10 && w
 20:29:26 up  4:04,  1 user,  load average: 0.00, 0.00, 0.00
USER     TTY      FROM              LOGIN@   IDLE   JCPU   PCPU WHAT
root     pts/0    1.2.3.4          18:24   10.00s  0.23s  0.00s w

So, write a cron job that reads this line and when the number is over 300 (5 mins) execute your command.


How ubuntu works around licensing to deliver ubuntu-restricted-extras?

Legal Notice Patent and copyright laws are different depending on the country you are in. You will need to get legal advice if you are unsure whether a particular patent or restriction applies to a media format you wish to use in your country.

I am not a lawyer so take these pointers as from a user but ...

ubuntu-restricted-extras is a metapackage. The actual packages are NOT on the installer; Canonical does not need to pay a fee for a metapackage.
It is up to the individual user to access if it is legal to use these. Mind the last sentence at the option: by checking this you accept the EULA. The EULA is not shown from the installer but accessible through the documentation.

  I thought philosophy of linux was "open source, maintained, non-encumbered by patents, not full of security issues, meet generic open source best practices"

That does not mean an individual user can not install proprietary software.


Bumblebee is something you can do after you've installed Ubuntu completely on your hard-disk.

Abouth the black screen after selecting "Try-Ubuntu".
You have to set the BIOS from "UEFI" to "Legancy BIOS".

Then you will get one screen further. Purple with two icons on the bottom.
Hit the [Esc]-key and choose your language.

With the next screen you can add options with [F6].
There you can activate "NOMODESET".

Select Try Ubuntu and start further.

The screen can go black and it can take a couple of minutes before the desktop can came up.

I hope I could explain it clearly enough.

Greetings, Erik


sudo -s
apt-get install privoxy
echo "forward-socks5 / localhost:9050 ." >>/etc/privoxy/config
systemctl restart privoxy

https://wiki.archlinux.org/index.php/ELinks#Tor_usage


How can I avoid tilda from creating a new configuration file each time it is lauched

/home/user/.config/tilda/ had the wrong permission

chmod a+rwx /home/user/.config/tilda


VLC fails to play dvds from external drive

ubuntu-restricted-extras is a meta-package that installs:

Support for MP3 and unencrypted DVD playback
Microsoft TrueType core fonts
Flash plugins
Codecs for common audio and video files

To install, run these commands:
sudo apt update
sudo apt install ubuntu-restricted-extras
sudo apt install libdvdread4
sudo apt install libdvd-pkg && sudo dpkg-reconfigure libdvd-pkg


Alternatives OBS - Open Broadcaster Software

Solution!

First:

Install FFMPEG

sudo apt-get update
sudo apt-get install ubuntu-restricted-extras
sudo apt-get install ffmpeg

Second:

Create a file named "obs-fix.sh" containing the following

INRES="1366x768" # input resolution
OUTRES="1366x768" # output resolution
FPS="30" # target FPS
GOP="30" # i-frame interval, should be double of FPS,
GOPMIN="15" # min i-frame interval, should be equal to fps,
THREADS="4" # max 6
CBR="1000k" # constant bitrate (should be between 1000k - 3000k)
QUALITY="ultrafast"  # one of the many FFMPEG preset
AUDIO_RATE="44100"
STREAM_KEY="***************************"
#SERVER="rtmp://live.twitch.tv/app/"
#SERVER="rtmp://live.justin.tv/app/"
SERVER="rtmp://usmedia3.livecoding.tv:1935/livecodingtv/"

ffmpeg -f x11grab -s "$INRES" -r "$FPS" -i :0.0 -f alsa -i pulse -f flv -ac 2 -ar $AUDIO_RATE \
 -vcodec libx264 -g $GOP -keyint_min $GOPMIN -b:v $CBR -minrate $CBR -maxrate $CBR -pix_fmt yuv420p\
 -s $OUTRES -preset $QUALITY -tune film -acodec libmp3lame -threads $THREADS -strict normal \
 -bufsize $CBR "$SERVER$STREAM_KEY"

and execute this script with ./obs-fix.sh

Work fine in ubuntu 15.10 and 16.04