Ubuntu 18.04 Cannot "Select All" in Folder

You will in principle find the option "Select All" when you right-click an empty space in the folder. The issue with nautilus is, however, that you cannot access that menu using right-click if your view is filled with file and folder names. This is a bug as old as the street. On Ubuntu launchpad, there is a report of 2010 and one of 2013, never marked as duplicates and never actionned.

Reported in 2012 on Gnome issues, the issue is finally solved in Nautilus 3.30, where the redesign of the path bar allows to have this menu available anytime as a right right-click on the folder in the path bar. Ubuntu 18.04, however, still ships with nautilus 3.26, because that was the last version that supports icons on the desktop.

There are quick alternatives to select all items, however:

Use the shortcut key Ctrl+a to quickly select all items.
Display the right-click menu for the folder by hitting Ctrl+F10, where you find "Select all" among the options.


Do not use useradd to create a password as it is a special type of password. From useradd manual, -p flag:

-p: The encrypted password, as returned by crypt(3). The
default is to disable the password. Note: This option is not recommended because the password
(or encrypted password) will be visible by users listing
the processes.

So the commands should be:
sudo useradd juliet -s /bin/sh
sudo passwd juliet #and type the password


help me my server seems to be sending spam!

I assume that spam is sent through the site, or injected into the site.

I recommend shutdown smtp and find place where spam is sending.

Assume this place in your php project.


What is the keyboard shortcut to switch to Applications tab in gnome3?

I was able to get to Applications tab using accessibility switch (Ctrl+Alt+Tab) - by hitting it several times it allows to select Applications panel. Same way to get back to windows panel.


First, reboot the system to clear out everything.

Next, open a terminal (ctrl+alt+f1) and run these commands:

airmon-ng check kill
ifconfig wlan0 down
iwconfig wlan0 mode monitor
ifconfig wlan0 up

Note that while this does not create a new interface, it still achieves the desired effect, by putting the existing wlan0 interface into monitor mode.


"No root filesystem defined" while installing Ubuntu on Virtual box

By "Erase and use the entire disk" it means the virtual hard disk created before proceeding with the installation XD not the Host Computer's actual HDD!
Thanks to this article for the information.


The limiting factor is probably the available disk space or the number of partitions you can create.
You can have three and more OSs installed, though I am not sure that W8 is a good candidate at the moment. It might not play nicely with other bootloaders, like Grub or EasyBCD.
Performance is unrelated to the number of OSs installed.


I'm not familiar with Virtual Box (I use VMware Player) but for the NIC config you should be able to change it from NAT to bridged. That should allow a different IP.


Black Screen after installing recommended Nvidia drivers. What to do?

Mostly nvidia drivers work well when you install option like "Nvidia drivers (recommended)" but sometimes not. Usually Ubuntu drivers app suggests more than one driver version, you should play around. If recommended went wrong you could reinstall and try newer driver version.or older. Since reinstalling takes time, it may not sound as a solution, on the other hand you are newbie, therefore it may take less time than to debug the problem.

You could press Ctrl+Alt+F1 or (F2,F3..) where you could login with your username and password and get into terminal, there you can type :

sudo tail -100 /var/log/syslog

and read some details about nvidia failing.

Restart X server instead of all system, from terminal type :

sudo /etc/inid.d/lightdm restart

for getting back into login screen (it can also be instead of lightdm xdm or gdm it depends on which version of ubuntu you installed xubuntu kubuntu etc.)

Apart from your video drivers problem you should be very careful about your data you don't want to lose on second partition. Even though it should be safe, before making any installation, it would be a good idea to back it up before playing around, especially if you are new to Linux, you never know when you will press the wrong button.

If you have a 1GB or less ram in your system I would recommend while partitioning your disk to create 512mb-1gb partition defined as a swap, which works like pagefile in windows. Whenever system is out of ram it uses hdd for storing chunks of data. I have seen very interesting linux machines behaviour after they get into "out of ram situation".

Also make sure your root partition does not run out of space, you can check in terminal typing df -h what is the usage of your root partition.


RXTX Library Ubuntu 14.04 Soft link to see the serial port

Linux udev assigns consistent port names when hotplugged into system. There should not be any need to create soft link, in-fact it is the job of udev.

When connecting arduino check "dmesg" command's output. It will tell you exactly what your system is doing.

Further consider using scm library for serial port communication https://github.com/RishiGupta12/serial-communication-manager


How do I implement a quit dialog in Gtk3?

There are several issues with this code.

The dialog.destroy() method will never be called, you return your function before this call.
Have a look at the Gtk.MessageDialog. It will handle some boilerplate code which you need with a regular Gtk.Dialog.
Read PEP-8. It's not a rule, but common practice. UpperCase names are intended for classes, attributes and methods should be camelCase or with_underscore.
The for-loop is inefficient. And the whole method could be indented one tab less.

Here is some sample code, pep-8 and the messagedialog still needs to be done.

def confirm_close(self, widget, event):
    unsaved = False
    for doc in self.Documents:
        if not doc.Saved:
            unsaved = True
            break # Break here, no need to check more documents

    if not unsaved:
        Gtk.main_quit()

    #TODO: build the messagedialog
    dialog = Gtk.MessageDialog(....)
    response = dialog.run()
    if response == Gtk.ResponseType.OK:
        # Really quit the application
        Gtk.main_quit()
    # Close the dialog and keep the main window open
    dialog.destroy()
    return True


What is the apt (apt-get) --option used for?

From man apt:

   -o, --option
       Set a Configuration Option; This will set an arbitrary configuration option.
       The syntax is -o Foo::Bar=bar.  -o and --option can be used multiple times
       to set different options.

For example,
if you are behind a proxy,
and want to test with different proxy setting values,
you could do this:

apt-get update -o Acquire::http::Proxy "http://yourproxyaddress:proxyport"

When you are not sure of the correct setting value, testing different values using the -o option can be more practical than editing a config file in /etc/apt/apt.conf.d, saving and re-running the command. The -o option let's you skip the file editing part, and play with different values more directly.

More generally, the purpose of this option is to temporarily override any configuration value.
As @steeldriver pointed out in a comment,
the available options and option syntax are documented in the apt.conf manual page (man apt.conf).


Tor hidden service file permission problem

There is a simple answer - AppArmor. It limits resources for you services. You can find details here man apparmor or look here http://wiki.apparmor.net/index.php/QuickProfileLanguage

So you have to add rules to /etc/apparmor.d/local/system_tor

# Site-specific additions and overrides for system_tor.
# For more details, please see /etc/apparmor.d/local/README.

/home/debian-tor/tor_keys/* rwmk,

Then sudo service apparmor restart
And it will work like a sharm.

sudo service tor restart

sudo service tor status

tail /var/log/tor/log

torify links my_abracadabra.onion

and so on...


This is a known bug.

According to one of the subscribers you can go around this by using these steps:

  sudo visudo

  then add the following lines

  Defaults env_keep="http_proxy"
  Defaults env_keep="https_proxy"

  then:

  sudo bash
  export https_proxy=http://[username:password@]www.proxy.com:8000/
  add-apt-repository ppa:<whatever>


Firefox will not even try to install Gnome extensions

Please make sure you have both gnome-shell-extensions and chrome-gnome-shell packages installed:
Install them as follows:

Install gnome-shell-extensions
sudo apt install gnome-shell-extensions

Install chrome-gnome-shell
sudo apt install chrome-gnome-shell

After that:

Install the Gnome tweaks tool as follows:
sudo apt install gnome-tweaks

Open the GNOME tweaks tool as follows:
gnome-tweaks

Select extensions from the left side menu and enable them.

Firefox gnome extensions should now install easily from this official web page (simply by flipping the OFF button on the top right to ON):
https://extensions.gnome.org/
You might need to log out and re-log in for the gnome extensions to work.


How to allow only one entry instance for Netbeans/Eclipse in Unity Launcher?

Effective solution found thanks to Java Swing Ayatana library.

Open your Netbeans IDE, then go to menu: Options / Plugins; And add the Java Ayatana plugin's remote XML catalog file: http://java-swing-ayatana.googlecode.com/files/netbeans-catalog.xml
 and then install it - (Restart NetBeans).

Illustration: http://hanynowsky.wordpress.com/2012/05/12/integration-of-java-swing-applications-with-unity-global-menu-in-ubuntu-12-04/
Credit: http://code.google.com/p/java-swing-ayatana/


See this answer to my proposed duplicate. You can achieve this using gnome-clocks.

To install it open Terminal and run

sudo apt install gnome-clocks

Once installed,

Search for "Clocks" in Activities overview and launch it.
Set a new world clock (or clocks) by clicking on "New".
Logout and login again.

You should see the added clock(s) in the drop-down dialogue after clicking on the clock in the top bar. Alternatively you may press super + M to open/close the dialogue.


the flash mem and camera don't work on windows xp installed by virtual box

Your VM must be configured this way that it can access your physical computer's devices. Have you enabled the CD drive and USB in your VM settings?


Virtualbox 4.3.26 dkms will not install properly on Linux kernel 4.1

Version 4.3.28 should work just fine with Linux 4.1.


How to install mysql without root access?

Without a package manager you can download source code. At the website you posted choose "Source Code" and then take the generic one: "Generic Linux (Architecture Independent), Compressed TAR Archive". Now you have to compile the source code. There are plenty of guides how to compile mysql manually.

Another option would be to download the Debian package from the list and unpack it manually:

ar x package.deb
tar xzf data.tar.gz

Then you find the binaries in the folder you unpacked the data.tar.gz.

But be aware, it is a pain, because you have to do this with all the libraries needed by mysql, too


Newly compiled kernel hangs at boot with no output

Instead of building the mainline kernel with make and installing it with make install you probably are better to try building a debian packaging from the kernel source and installing the .debs.  That way you can easily remove it too.
unxz -v linux-5.7.11.tar.xz
tar -xvf linux-5.7.11.tar.xz
cd linux-5.7.11
cp /boot/config-5.4.0-42-generic .config

make deb-pkg INSTALL_MOD_STRIP=1
cd ..
sudo dpkg -i *deb


Gparted won't re-partition under 16.04.4

The error message "/dev/sda: unrecognised disk label" indicates that there was no partition table recognized on the drive.  Perhaps the important sectors containing the partition table were somehow overwritten.  Another possibility is that the drive did not contain a partition table and was perhaps entirely formatted with a file system.

You might wish to check the health of the drive with a program such as gsmartcontrol to see if the drive is reporting excessive errors.


How to open wubi's .disk files under windows?

Explore2fs did not work for me (don't know why)

An alternative that definitely works is ext2explore, which can be downloaded from the following website

http://sourceforge.net/projects/ext2read/files/

Download it and browse for the .disk file where you installed ubuntu. It worked for me, even in kubuntu.


Usage: logrotate [-dfv?] [-d|--debug] [-f|--force] [-m|--mail=command] [-s|--state=statefile] [-v|--verbose] [-l|--log=logfile]
[--version] [-?|--help] [--usage] [OPTION...] < configfile >
sudo logrotate -f /etc/logrotate.conf
It has to be run on a config file... This will run logrotate on all the logs  designated by the config.


Skype Video Call Not Working Ubuntu 11.10

maybe this video will help, it's on Greek but the capitations are on English, and there's summary in video description.

http://www.youtube.com/watch?v=WeaLCzB4qy8


Move files from Ubuntu to windows or change windows files(media) files with ubuntu

I am also a quite new user but I think you should mount the windows partition on read and write mode.

I did not find the exact solution but it must be there :
https://help.ubuntu.com/community/MountingWindowsPartitions


How to add a PPA which does not include my Ubuntu distribution?

In /etc/apt/sources.list.d, open the file that contains the name of the PPA in a text editor. The name will be something like stevedh-smap-trusty.list. Then, after the URL on the first line and the second line, change trusty to precise (since that's the most recent Ubuntu version supported by the PPA). For example:

deb http://ppa.launchpad.net/stevedh/smap/ubuntu precise main
deb-src http://ppa.launchpad.net/stevedh/smap/ubuntu precise main

Save the file and run sudo apt-get update.

That being said, note that because of library updates and packaging changes between Precise and Trusty, there is no guarantee that you'll be able to install the software from that PPA, much less run it.


Ubuntu installation issues, I've seemingly lost 65GB of hard disk space

MBR partitioning scheme, used since the times of MS-DOS, only allows for 4 partitions to exist on a physical device. As a work-around, one of these partitions can be an "extended" partition, which can act as a container for more partitions (the partitions outside of an extended partition are called "primary".

So, if you have 4 primary partitions on your disk - even if you resize one of them you won't be able to use that space.

What you need to do is:

backup data on the last of your partitions
delete it using gparted
create an extended partition
create two (or more) new partitions inside the extended partition, use one of them to install Ubuntu.

(or, alternatively, you can delete some other less important partition and then move other primary partitions around to free up some space - the point is the same, you need to remove one of the primary partitons to be able to create an extended partition. You can then create a partition inside the extended partition and restore the data you copied from the primary partition you deleted... hope this makes sense)

UPDATE: here's the confirmation that HP G62 laptops come with 4 primary partitions already taken. Also there are some suggestions how to fix this.

Here's a thread on ubuntuforums with some screenshots and suggestions.


install boot loader again with boot-repair, it should work.


Is it possible to accidentally format a Truecrypt-encrypted drive?

The only way to format the drive that is installed by default is the Disk Utility, or with the liveCD/USB but accidental formatting should not be possible. It cannot be done via Nautilus.

Disk Utility needs root privileges to make any changes so while you can get info on the disks and partitions, it cannot do anything else without a password. So if they have your administrator password the could reformat the drive but not with just a casual keystroke, they would have to

select the drive and then
select the option to reformat
select the file-system to reformat to
confirm and then enter your password....

When booting form the liveCD there is no password needed but to reformat they would first have to boot into the livedCD and then follow all the steps above minus the password.  So it could be done intentionally but not accidentally.

If you don't want them to have the password you could set them up a limited user account and then they would not be able to use any sudo commands, or setup your account to login without a password, (highly discouraged if this is a laptop in case of temporary loss). Slightly less secure if it's a desktop but anyone that has the computer in his possession and has a little know how can reset your password anyway....(can be done on Windows as well)

The fact that it is encrypted and by not be readable by Ubuntu makes no difference, the Disk Utility will behave the same.... the encrypted partition should just be listed as "unknown "

If you want you can remove the Disk Utility from the Software Center, and reinstall it if needed later; may be needed to erase a USB key or other drive but will not work on mounted drives so if you need to reformat you main drive you will need to use the liveCD/USB anyhow.


Did you try using an Ubuntu LiveCD to boot into live mode? The system will run from your RAM and the data on your hard disk will remain untouched, as far as I know. You can then connect an external drive to copy and backup your data before you do anything else.

For the future, please spend a little more time wording your question and do a regular backup, for example with CrasPlan Backup.


New 12.10 Install, Windows Not in Boot Menu

The Boot Repair option worked perfectly for me. Installed 12.10 after windows 8, the install did not recognize win8, using the boot repair utility found the windows partition and successfully added it.


When you ran sudo adduser cloudera, you used sudo. I am going to refer to this as the primary user.

If you already have ssh installed

If you already have ssh installed, you shouldn't need to do anything. You should be able to ssh into it directly.

If you don't have ssh installed

Install it in the primary user with the command sudo apt-get install openssh-server. This will install it system-wide, enabling it for all users.

If you don't know whether you have ssh installed

Run dpkg -L openssh-server. If there is any output, you have it installed. Otherwise you don't.


How do I install Epson ET-2550 driver where lsb <=3.2 is required?

UPDATE for Ubuntu 19.10
I realized that with the generic EPSON ET Series drives it doesn't print correctly (prints ASCII carachters :(), so you must modify the Make and Model from "Local Raw Printer" to "Epson Expression ET-2550 EcoTank - CUPS+Gutenprint v5.3.1"
UPDATE for Ubuntu 18.10
I had problems with the configuration in Ubuntu 18.10 with CUPS Server.

Enter into the CUPS server Web (http://localhost:631/admin/)
Look for the Option "Add New Printer" and add your Ubuntu User and Pass
Here there are several Options --> Select the Driverless one (in order to have it by the Hostname instead by the IP) "EPSON ET-2550 Series (EPSON ET-2550 Series (driverless))" (I have checked also "Share in Network")
Select the Model (if NOT listed, install the Printer Drivers, 1st direct from Ubuntu "lsb", if doesn't work download from the EPSON Page)
Try to Print something

IMPORTANT: If you can not print anything probably you have a problem with the .local ending in the Hostname (in my case EPSON14562B)

Go to the Printers Menu --> Additional Settings in Ubuntu Settings
Go to Properties of the Added Printer
Replace ".local" with ".lan" (or remove it) from the Device Address: ipp://EPSON14562B .local :631/ipp/print --> ipp://EPSON14562B .lan :631/ipp/print or directly ipp://EPSON14562B:631/ipp/print
Print again :)

ORIGINAL Post for Ubuntu 16.10
I have the same All-In-One Printer ET-2550, and those are the steps I followed to configure with the WLAN connection through my Home Router in Ubuntu 16.10 64bits.

First of all connect the Printer to your Home Router using the Display and the Assistant Configurator from the Printer.

Insert the Local IP Address in a Browser (i.e. Firefox) to check that it is the correct IP (you can check it in the Router), in my case:
http://192.168.178.33 (you can also use the Printer Hostname i.e. http://epson14562b:631)

Copy it! We will need it later in Ubuntu Configurator

Now You can go to Ubuntu:

System Properties-->Printer-->Add a New Printer
In the Network Printer Drop Down, wait till Appears your Printer EPSON (with IP 192.168.178.33 in my case) and Select it and press continue.
Follow the Driver Assistant, choosing your EPSON printer from the list.

If your EPSON Model doesn't appear you have to Install the Drivers first and go to Point 4 again.

Test Print a Page, in my case didn't work!
If this doesn't work change the URL of the Printer (in the Printer Properties) for this one (Printer IP + 631 Port): https://192.168.178.33:631/ipp/print (better solution use the Printer hostname ipp://EPSON14562B:631/ipp/print)
Test Print a Page, in my case NOW works! You can print from any place of your Home :)

You can set a fixed IP to your Printer in your Router configuration in order to avoid probably change of the IP. (Not necessary if you use the hostname of the Printer)
The Scanner works perfectly with the Application "Simple Scan".
To Download the EPSON drivers
Try to configure first without installing any EPSON driver.
If the Scanner or/and the Printer are not correctly detected then Install Drivers
Printer
sudo apt-get install lsb
sudo apt-get install printer-driver-escpr

If you want the Epson "Printer Utility" download the .deb Package from:
http://download.ebz.epson.net/dsc/search/01/search/searchModule

Install them the way you prefer!
Scanner
http://support.epson.net/linux/en/imagescanv3.php

Download Ubuntu 16.10 64bits package.
https://download2.ebz.epson.net/imagescanv3/ubuntu/latest1/deb/x64/imagescan-bundle-ubuntu-16.10-1.0.0.x64.deb.tar.gz

Extract it and execute the "install.sh" File.


control xdotool script from keyboard or mouse

I found a rather simple way to implement a keyboard interrupt, using python3 (it must run as root to capture the keys). So I wrapped xdotool in a python3 script that is able to read the 'state' your keyboard while the window the script is running in is not active.

I'm sure the below could be modified to stop/continue instead of just exiting the whole thing. But in this simple example the F3 key is used to stop the loop.

This probably works with python 2.7 (I haven't tried, but replace pip3 with pip below to try it out), it is tested with python3 on Ubuntu 16.04.

First of, you need to install two pieces of software: xdotool and pip3

sudo apt install xdotool pip3

Then you need to install the keyboard package for pip

pip3 install keyboard

The script looks like this, save it, make it executable (chmod +x, this is technically not required) and run it with sudo or as the root user.

#!/usr/bin/python3
import keyboard
import subprocess
import os

def key_press(key):
    if key.name == "f3":
        os._exit(0)

keyboard.on_press(key_press)

while True:
    subprocess.call(['/usr/bin/xdotool', 'click', '1', 'sleep', '0.02'])

I don't have a complete understanding of the keyboard API (or Python for that matter), but from my understanding, the keyboard.on_press invokes a callback (in this case to the key_press function) every time you press down a key.
So if you wanted to change what happens when the key is pressed, change the code inside the if statement in key_press. If you wanted to change which key to listen to, change f3 to another key. If you want to listen to any keypress, simply remove the if line and the indentation from the next line.

Please note the bottom line where an array is used to contain all the arguments for xdotool. If you wanted to add more arguments, you would have to add more strings to the array, all arguments HAVE to be strings.


Connect to ethernet, and run sudo apt update && sudo apt upgrade && sudo apt dist-upgrade

This command updates your system fully. That way, if there is a fix already in the new kernels (which get updated extremely frequently) you get it.


Converting media server to Ubuntu: Do I need to convert NTFS drives with movies?

EXT4 theoretically performs better than NTFS but full read-write support for NTFS is built into Ubuntu, so you shouldn't have any problems with the existing setup, providing you take appropriate newbie precautions when configuring your installation. This includes making sure that the drives are properly closed by windows by performing a full shutdown before booting into a live disk, and as suggested by @Redbob, it's a good idea to disconnect all data-crucial media when performing a new installation to avoid accidental formatting.

Please see related questions for a comparison of NTFS and EXT4 (the default for the current version of Ubuntu)

Why ext4 File System is better than NTFS?


Disks Utility Drive Settings – how does it work? (no documentation available)

Unfortunately, gdisks hasn't seen much development lately, so the "old" way is the "new" way again...  The disadvantage of FLOSS at work.  :-(

So as development is stalled, manuals are probably never going to happen. ;-(

Sorry to be the harbinger of bad news...


How can I run Dwarf Fortress in text mode (ncurses) on my Linux VPS?

I was able to recreate the segfaulting by running df on a regular Ubuntu install with X turned off.

...
(Dwarf_Fortress:5346): Gdk-CRITICAL **: gdk_window_new: assertion `GDK_IS_WINDOW (parent)' failed
Segmentation fault

I suspect the problem is that this game expects to have a functioning GL driver available.  And for that you need X running.  But a VPS doesn't have X!

Instead, use Xvfb, which is a "fake" virtual X.  You'll need to install xvfb and whatever dependencies it wants (probably xorg-server-core and a bunch of other stuff that may not be installed on Ubuntu Server).

Start the fake xserver up like this:

 $ Xvfb :1 -screen 0 1024x768x16 &

Then make sure your DISPLAY variable is pointed to it:

$ export DISPLAY=:1
$ ./df

I also needed to disable sound and run in TEXT mode, but it worked this way, with no X running.  I hope it works for you.


How can I change icon size in Empathy in 13.04?

It cant be changed without modifying the source code, or writing some sort of extension of your own. I find this just as frustrating, makes it more difficult to use at work.


From that guide, you're creating a Python virtual environment:

python -m virtualenv envsp
source env/bin/activate

Using the above, you're creating a folder called envsp which will hold your virtual env.

To enter it, use:
source envsp/bin/activate

Seems like just a typo in the guide.


In my case, It wasn't an issue with the drivers or swap,
I downgraded the Linux kernel from 5.4.0.28 to 5.3.0.28
by selecting advanced Ubuntu options in grub,booting into old kernel and removing the problematic kernel (here 5.4.0.28) by:
sudo apt-get purge linux-image-unsigned-5.4.0-28-generic

which gives error:
rmdir: failed to remove '/lib/modules/5.4.0-28-generic': Directory not empty.

manually remove the directory by:
sudo rm -rf /lib/modules/5.4.0-28-generic

Then update grub:
sudo update-grub2

... works like charm!


This has been reported as a bug, you can check it out here -
https://bugs.launchpad.net/ubuntu/+source/udisks/+bug/1059872

you can mention that this bug affects you (at the aforementioned site, i.e.), it'll help give the bug greater attention.

you can always use gparted for formatting a disk.
to get gparted, you can use the software centre or enter the following command in the terminal

  sudo apt-get install gparted

choose your device, unmount it and then right-click to open a menu. within the menu you'll find a 'format to' option, use that to format it to whichever file format you wish to use, and click on apply.

That should work out perfectly.


Is Cairo dock 2.4 fully compatible with Intel i965?

As unity is playing ball, it'd be fair to say that cairo will to.


Dropbox install stuck at 99%, how do I fix it? (and any dpkg errors)

There already is a bug filed: 1016559

If you have a LaunchPad account, don't forget to add your name to the bug.

Work arounds are listed here.

  Download the Dropbox .deb file from: https://www.dropbox.com/install?os=lnx
  Open the .deb with Ubuntu Software Center and begin installation
  When you see the screen saying "Start Dropbox to finish installation", press CLOSE
  Install the dropbox daemon (nautilus-dropbox) using this command (from https://www.dropbox.com/install?os=lnx):

cd ~ && wget -O - "https://www.dropbox.com/download?plat=lnx.x86_64" | tar xzf -

  [ for 32bit, just change detail to ?plat=lnx.x86 ]
  Restart computer

  Now you should have Dropbox working, including the notification icon
  and the Dropbox icon overlays in Nautilus.

Forum thread on the Dropbox Forums
Another thread from the Dropbox forums


Dual boot Windows 10 (LEGACY) and Ubuntu 18.04 on separate Drives

To fix this issue, make windows 10 UEFI instead.

to do that use the windows built-in mbr2gpt in windows terminal or, alternatively, follow this video guide : https://www.youtube.com/watch?v=hfJep4hmg9o&feature=youtu.be&t=55

once you've done that reboot into ubuntu and run :

sudo add-apt-repository -y ppa:yannubuntu/boot-repair && sudo apt update && sudo apt install -y boot-repair

this will allow both windows and ubuntu to appear in the boot menu.


Display cuts off launcher, everything's blurry, Hulu choppy, system slower than Vista

I am assuming 12.10 and not 12.1.
This release is still not stable, and the GPU problem in 12.10 have been bugging every other user since the release. Try popping into IRC channel #ubuntu, every other user is complaining about the same problem. I have an ATI Readon GPU that is causing the same problem with ATI drivers but reverting back to the X drivers I managed to reduce the problem down to a working environment. You can try to revert to X drivers by going to System setting > Software sources > Additional Drivers and select X.org X Server

I'd recommend you to stick to 12.04 if you are new to linux as that is pretty much stable and also a long term supported release.


How to install Ubuntu Touch on Nexus 4 with broken touchscreen

Unlocking bootloader does not require a functional touchscreen, boot menus are fully controllable by hardware buttons.

Commands history:

sudo add-apt-repository ppa:ubuntu-sdk-team/ppa
sudo apt update
sudo apt install ubuntu-device-flash phablet-tools

# Press Down and Power buttons on the phone, connect the USB cable
fastboot oem unlock
# Up, Power to agree
ubuntu-device-flash touch --channel=ubuntu-touch/stable/ubuntu --bootstrap --developer-mode --password <password>
# phablet-config writable-image
# phablet-config welcome-wizard --disable
adb shell

sudo nmcli dev wifi con "<ssid>" password "<password>"

USB mouse through OTG cable doesn't work, but generates a stacktrace from kernel in dmesg, maybe it will work later.


How do I change proxy settings automatically based on the network that I connect to?

The author of the program claims that proxydriver can do that for you.

http://marin.jb.free.fr/proxydriver/
https://wiki.archlinux.org/index.php/NetworkManager#Proxy_settings


Replace

Runtime.getRuntime().exec("spd-say \"" +message+ "\" -p 100 -i 100 -t female1");

with

Runtime.getRuntime().exec(new String[]{"spd-say",'\"'+message+'\"',"-p 100 -i 100 -t female1");

and it will work.
Cheers!


Ubuntu 19.10 - Night Mode does not change the color on screen

October 20, 2019

This was apparently fixed 4 days ago and should appear shortly in Ubuntu updates:

gamma ramp prediction broken for redshift-gnomerr

The source code changed (if anyone cares) is here:

kms/crtc: Read gamma state when prediction failed

November 29, 2019

It's been reported in comments bug fix is now "live" in Ubuntu 19.10.


it was answered by https://askubuntu.com/users/757577/moosee333 in the comment

  The manual installation of nvidia drivers worked for me. I hope it helps you! See: Installing NVIDIA drivers for Ubuntu 18.04 – moosee333 May 22 at 1:45


Presuming you're trying to rebuild as in restore redundancy to an array that has lost one disk

If the array is not already assembled, assemble it: mdadm --assemble --scan /dev/md1 (if it's in the config file) or mdadm --assemble /dev/md1 /dev/sda2 /dev/sdb2 /dev/sdc2 /dev/sdd2. If one of the disks has failed, just leave it off the line.
If the rebuild was needed because because of an unclean shutdown, etc. it should happen automatically now. You can watch the status by cat /proc/mdstat. NOTE: If it says its in 'auto read-only mode', you need to write the the array (mounting the filesystem surely will), or use mdadm -w /dev/md1 to get it to start.
If the rebuild is because of a failed disk, add the replacement disk to the array: mdadm -a /dev/md1 /dev/sde2 (sde2 being the new disk). You might have to do mdadm --run /dev/md1 as well.

If by "rebuild" you mean recover from something that is supposed to be fatal to RAID5 (e.g., double-disk failure), then that's more complicated, and the steps depend on exactly what lead up to the failure.


Is libunity planning on including functions for Unity Lenses?

Note: The user visible name is Lenses, however in the code and packages they're still referred to as Places. "Places" as a term will be fully retired in 11.10

Both default Lenses, unity-place-files and unity-place-applications, are in fact based on public API exposed via libunity.

Unfortunately there are no API docs available for libunity yet - but that will change in the weeks to come. Monitor planet.ubuntu.com or watch the Natty archives for a libunity-doc package. For now there is a simple example in lp:unity-place-sample, if you cross ref that with https://wiki.ubuntu.com/Unity/Lenses you may have a chance of getting something going.

Another important library when writing lenses for Unity is Dee. It's a data model library used to do ad-hoc sharing of data models between processes (in this case the place daemon and Unity). Dee is fully documented and you can find the docs in the libdee-doc package (or you can build it yourself from lp:dee).

To grab the code for either project you can do:

bzr branch lp:unity-place-sample
bzr branch lp:dee


I don't think old-releases have local country mirror, you can try main mirror instead.

sudo sed -i.bak 's/ca.old-/old-/g' /etc/apt/sources.list
sudo apt update

You should upgrade to supported releases, currently it's Ubuntu 19.10, and newest 20.04 LTS.


Install ppa-purge in your system

sudo apt-get install ppa-purge

Use ppa-purge to remove the PPA you installed

sudo ppa-purge ppa:lubuntu-desktop/ppa

Make sure that lunbuntu-desktop is not installed any more and try to remove further dependencies that the package installed

sudo apt-get remove --purge lubuntu-desktop

Re-install ubuntu-desktop let the system install any missing packages

sudo apt-get install --reinstall ubuntu-desktop

What the first command does is install ppa-puge, its a small tool that removed PPAs from your system and attempts to install the previous version packages.

We are going to use it to remove ppa:lubuntu-desktop/ppa and any packages that you installed from that PPA with the second command.

The third command will remove the package lubuntu-desktop and any dependencies it installed in case ppa-purge missed any of those.

With the fourth command we will install ubuntu-desktop and any missing packages.

After this is all done you should log off and back on and hope that your desktop has been restored to normal.


Errors were encountered while processing: jitsi-meet-tokens

If nothing else works, try this. First, back up your status file:

sudo cp /var/lib/dpkg/status /var/lib/dpkg/status_bk

Open the current status file using your favourite text editor

sudo nano /var/lib/dpkg/status

Find and remove all of the text about the package you want to remove, in this case:

Package: jitsi-meet-tokens
Status: deinstall ok half-installed
Priority: extra
Section: net
Installed-Size: 53
Maintainer: Jitsi Team <dev@jitsi.org>
Architecture: all
Source: jitsi-meet
Version: 1.0.1073-1
Depends: debconf (>= 0.5) | debconf-2.0, prosody-trunk (>= 1nightly607), libssl-dev, luarocks, jitsi-meet-prosody
Description: Prosody token authentication plugin for Jitsi Meet
Homepage: https://jitsi.org/meet

Save, exit, and run

sudo apt-get update

Source: Linux Mint Forums


mtab is what's currently mounted. fstab is the list of things to mount at boot, and some static mount points for mounting by hand.

You can easily add a cdrom mount point (it looks like apt-cdrom needs one):

/dev/scd0       /media/cdrom0   udf,iso9660 user,noauto     0       0


You can use cu.

$ sudo apt-get install cu

You can connect to your modem with:

$ cu -l ttyACM0

(with: ttyACM0 being the device /dev/ttyACM0)
You should get a response:

connected

At this point you can use any of the standard AT commands such as to test dialing:

ATDT 123-456-7890

You should have your userid set to the group dialout for permission to access the modem.

You can exit the cu application with "~." (tilde dot).

You can find other Hayese commands at:

http://en.wikipedia.org/wiki/Hayes_command_set


GRUB not showing Windows 8.1 and Ubuntu 14.04.2 after Ubuntu 14.10 installation

if you have a way to access at least one Ubuntu installation, the answer goes as follows:
1. log in using Ubuntu intallation
2. sudo apt-get update && sudo apt-get dist-upgrade
3. grub-install
4. update-grub


Installing Ubuntu 14.04/14.10 on a UEFI laptop with Nvidia GeForce 840M

NVIDIA works perfectly in 15.04, I no longer get any shut down issues, and I can easily switch between Intel and Nvidia.

I didn't download any drivers, I simply installed 15.04, went to Additional Drivers and selected the proprietary Nvidia 346.59 driver and rebooted, everything went smoothly on the graphics card side although there is the occasional tearing when using Nvidia though it's probably Nvidia's fault.


Trying to install kubuntu from disc but can't do it

If you did not have any technical problems with your Ubuntu but want to switch for other reasons, maybe its an option to not un-install it at all. You can just install Kubuntu 'on top'.
That works nicely, because in all variants the underlying Linux is actually the same. The differenc is only in the desktop and some software choices.
I do not know Kubuntu actually, but I did the same thing to get from Ubuntu to Xubuntu. Here is what I did:

Just start Ubuntu as usual and open a Terminal

Install the small program "tasksel", which is not installed by default. If you are not sure, just enter the command, it will do nothing if it is installed already
sudo apt install tasksel

It will ask your password.

Run tasksel. Its will give you a small list of packages to install. The nice thing is that it can install a full desktop flavour with one click.
sudo tasksel

use the cursor keys up and down and SPACE bar to select a package to install. I went to "Xubuntu-desktop", pressed space, then TAB to get to the OK button and ENTER. Then it started the installation. Have a coffee.

When done your are either logged off, or just manually log off.

In the login window, you see a little button which pops out a list. For me it gave Ubuntu, Xubuntu and xfce. These are the different desktop themes. I did chose Xununtu and it got me to the Xubuntu desktop.

The nice thing is that you can keep multiple desktops in parallel. They do not take too much space. If you want you just uninstall the old one.
Hope it helps


apt-get does not support this (nor does any frontend of dpkg that I know of, including aptitude and Synaptic). You an use the CVE tracker: https://people.canonical.com/~ubuntu-security/cve/ to find out the matching package, but there's no automatic way.


How to change from Ubuntu touch stable channel to rc-proposed

Install the Terminal app from the store (or if you have enabled developer mode, you can use the phablet-shell tool over USB connection). If using Terminal app on the phone, you may need to disable screen locking Battery Settings first, as if the screen locks, the Terminal app (and its child processes) will be stopped. You can then change the setting back after switching channels.

Then, on the phone, run sudo system-image-cli -vvvv --switch $newchannel where $newchannel is the new channel you switch to switch to. For different devices, this channel may be different. For example, on the BQ Aquaris E4.5 and E5 Ubuntu Edition phones, the channel should be ubuntu-touch/rc-proposed/bq-aquaris.en to get rc-proposed. You can use system-image-cli -i to show current information, and generally just replace the stable portion of the existing channel name with rc-proposed to get the right channel. You can also perform the same action in reverse to switch back.


Virtualbox 5.2 has no Global menu on Ubuntu 16.04

I think that this issue is related to the "Qt Theme issue" (https://www.virtualbox.org/ticket/17218), and is caused by the usage of an internal Qt 5.6.1 library, needed by virtualBox 5.2.

Ubuntu 16.04 has Qt 5.5.1, that comes with custom theme, integrated with Gtk / Unity environment, but VirtualBox 5.2 need Qt 5.6.2, and so uses an integrated standard version of the library.

I think that the integrated Qt library not only does not have the custom theme, but also does not work with "global menu".

So the only solution I found is to enable the standard menu in the VM settings, under section "User interface".


How to use the left and right arrow keys in the tclsh interactive shell?

This functionality appears to be provided by the tcl-tclreadline package. From apt-cache show tcl-tclreadline:

Description-en_CA: GNU Readline Extension for Tcl/Tk
 tclreadline adds GNU Readline support to standard Tcl/Tk.  It provides
 interactive command editing and history for Tcl shells (this must be
 enabled on a user-by-user basis) and allows the use of GNU Readline
 features in Tcl programs.

Once you have installed the package, either from the Software Center or via the command line using sudo apt-get install tcl-tclreadline, you can enable it for interactive tcl shells by adding

if {$tcl_interactive} {
  package require tclreadline
  ::tclreadline::Loop
}

to your $HOME/.tclshrc file as explained on the tclreadline project homepage.


Cannot open MATLAB with sudo on Ubuntu 16.04

Yes, sudo has its own secure_path. From man sudoers:

 secure_path   Path used for every command run from sudo.  If you don't
               trust the people running sudo to have a sane PATH environ‐
               ment variable you may want to use this.  Another use is if
               you want to have the “root path” be separate from the “user
               path”.  Users in the group specified by the exempt_group
               option are not affected by secure_path.  This option is not
               set by default.

(note that it is set by Ubuntu's default /etc/sudoers).

If you decide to modify it, remember to use visudo rather than your regular editor to avoid locking yourself out in the event of syntax errors.

A better option might be to create a symbolic link from somewhere that's already on the Ubuntu sudo secure_path e.g.

$ ls -ld $(which matlab)
lrwxrwxrwx 1 root root 35 Apr 11  2017 /usr/local/bin/matlab -> /usr/local/MATLAB/R2017a/bin/matlab

Best of all would be to arrange your device permissions so that it is not necessary to run matlab as root.


Remove Google Chrome Icon From Dash Search

Let's check for the remaining launcher:

ls /usr/share/applications/google-chrome.desktop

if present, remove it with

sudo rm /usr/share/applications/google-chrome.desktop

You may also need to check the applications folder in the user's home directory: ~/.local/share/applications/ and remove google-chrome.desktop. (thanks Tchalvak)


Help with iptables rule, how to allow port before REJECT rule?

Something like that:

iptables -I INPUT -p tcp --dport 47657 -j ACCEPT

If TCP is the protocol you will use on this port.
Remember that: -A is to append a rule in IPTABLES, it will always put in the end.
If you use -I is to give it priority so it will put the rule in the beginning of the rules. You might need to put it in a exactly position if you have more rules that might mess with this rule.


Meaning of "b" and "c" in file privileges description (output of ls -l)

http://www.gnu.org/software/coreutils/manual/html_node/What-information-is-listed.html#index-verbose-ls-format

‘b’
block special file

‘c’
character special file


Ambiguity using "ls -l" and "file" commands on a qcow file

From Qcow in Wikipedia:

  One of the main characteristics of qcow disk images is that files with
  this format can grow as data is added. This allows for smaller file
  sizes than raw disk images, which allocate the whole image space to a
  file, even if parts of it are empty.

So the file size is really 13MB, but it can grow up to 20GB when data is written to it. Example:

$ qemu-img create -f qcow2 test.img 2G
Formatting 'test.img', fmt=qcow2 size=2147483648 encryption=off cluster_size=65536 lazy_refcounts=off
$ ls -l test.img
-rw-r--r-- 1 carvalho carvalho 197120 Jul 18 09:30 test.img
$ file test.img
test.img: QEMU QCOW Image (v2), 2147483648 bytes

An empty qcow2 file was created. It can hold a 2GB filesystem, but for now it only occupies 197KB in disk.

From http://en.wikibooks.org/wiki/QEMU/Images:

  The "cow" part of qcow2 is an acronym for copy on write, a neat little
  trick that allows you to set up an image once and use it many times
  without changing it. This is ideal for developing and testing
  software, which generally requires a known stable environment to start
  off with. You can create your known stable environment in one image,
  and then create several disposable copy-on-write images to work in.

  To start a new disposable environment based on a known good image,
  invoke the qemu-img command with the option -o backing_file and tell
  it what image to base its copy on. When you run QEMU using the
  disposable environment, all writes to the virtual disc will go to this
  disposable image, not the base copy.

From the qemu-img manpage:

  If the option backing_file is specified, then the image will record
  only the differences from backing_file. No size needs to be specified
  in this case. backing_file will never be modified unless you use the
  "commit" monitor command (or qemu-img commit).

Example:

$ qemu-img create -f qcow2 -o backing_file=test.img test01.img
Formatting 'test01.img', fmt=qcow2 size=2147483648 backing_file='test.img' encryption=off cluster_size=65536 lazy_refcounts=off
$ file test01.img
test01.img: QEMU QCOW Image (v2), has backing file (path test.img), 2147483648 bytes

In your case /var/lib/nova/instances/_base/035db99541e92b5cca93bf18a997d626f512b73d is the backing file. I don't know what is the expected bahavior if you try to use your qcow file without the backing file.

About /var/lib/nova/instances in OpenStack documentation:

  This directory contains the libvirt KVM file-based disk images for the
  instances that are hosted on that compute node. If you are not running
  your cloud in a shared storage environment, this directory will be
  unique across all compute nodes.

  /var/lib/nova/instances contains two types of directories.

  The first is the _base directory. This contains all of the cached base
  images from glance for each unique image that has been launched on
  that compute node. Files ending in _20 (or a different number) are the
  ephemeral base images.

  The other directories are titled instance-xxxxxxxx. These directories
  correspond to instances running on that compute node. The files inside
  are related to one of the files in the _base directory. They're
  essentially differential-based files containing only the changes made
  from the original _base directory.


Something is using my camera on Ubuntu 14.04.2

If you think that someone is using your camera, you should probably disconnect from the Internet just to see if it stops. If it doesn't, then it's probably a program on your computer, or perhaps a compatibility problem since on Windows it behaves differently.


Installing Ubuntu from a windows PC on to a USB connected Hardrive

Installed Ubuntu systems are rather portable between (intel/amd) PC computers. Not as portable as live systems, because the live systems have a mechanism to try more drivers to critical hardware, for example graphics and wifi.

If you avoid installing proprietary drivers, and the computers work without proprietary drives, you will be able to install Ubuntu in one computer and run it in another computer. My son has an Elitebook 8560p, which is similar to yours, and it works with Ubuntu without any proprietary drivers.

In this case you should also consider the issue of UEFI versus BIOS. The Elitebook is probably booting in BIOS mode, while the computer with the Asus motherboard might be booting in UEFI mode. And you should install Ubuntu in the mode that you intend to boot it - or use an installed system, that boots in both UEFI and BIOS mode. I made compressed image files of such systems, that you can install with mkusb according to the following link,

help.ubuntu.com/community/Installation/UEFI-and-BIOS

Use one of these compressed image files, or use the link only to help you create your own installed system from an Ubuntu iso file.

If you create your own system, it helps to remove the internal drive (with Windows), so that the bootloader will written to the correct target drive (the drive with the USB - SATA connection). This is particularly important if your computer is booting in UEFI mode, but as mentioned before, if the Elitebook is booting in BIOS mode, you should boot your computer with the Asus motherboard in BIOS mode, when you install Ubuntu.


Xfce
You simply set the "Key used to grab and move windows" under the Accessibility tab of the Window Manager Tweaks program found in the Whisker Menu.
You can even set it to None. But since Super on it's own doesn't open any dashy menus in Xfce I'm pretty comfortable using Super as the key used to grab and move windows.
Unity

Open a terminal (Ctrl+Alt+T) and type sudo apt-get install dconf-editor. Enter your password when prompted and after the installation is finished type dconf-editor to open the Configuration Editor.
Now either hit Ctrl+F and use the hereby summoned field to search for mouse-button-modifier or navigate to org.gnome.desktop.wm.preferences and find the same.
Change it's value from <Alt> to something else (<Super> will probably work best) and enjoy your improved workflow!

NB: Leaving the field empty - in Unity - will get you stuck in drag-mode, unable to click the "Set to Default" button. You can bring the focus to this button by pressing Tab until a fine orange rim shows up around it. Then press Space and repeat step 3.


How to add a latin american keyboard in 17.10?

It's there. If you click a Latin American country, e.g. Spanish (Argentina), you are taken to a sub menu which includes Spanish (Latin American).

Edit:

I happened to have the Spanish language installed, and under that condition the above advice applies. However, if you want to enable the Spanish (Latin American) keyboard layout without installing the Spanish language, you can add some Latin American locale. Open a terminal window and run for instance:

sudo locale-gen es_AR.UTF-8

Now, if you open Settings -> Region & Language and select Spanish under Input Sources, the sub menu you are taken to will include Spanish (Latin American).

<rant>
The design makes no sense. Keyboard layouts should not have anything to do with which locales you happen to have generated. Personally I think this a design bug which should be reported to the GNOME developers.
</rant>

Issue submitted: https://gitlab.gnome.org/GNOME/gnome-control-center/issues/82


Right-click on home folder in unity launcher does not populate the bookmark list

Actually I solved my issue by uninstalling Unity Window Quicklists, since I did not use it as much as the shortcuts.


Trying to install WI-FI Driver on fresh install with no internet

A .deb is package, as in program.deb, for Ubuntu like .exe is for Windows or .dmg is for Mac.

How can I either install GCC without internet

You can get a .deb of the gcc from https://packages.ubuntu.com/disco/gcc by clicking on your architecture at the bottom of the page and then selecting a mirror. Then move the download to your computer with something like a USB drive.

or find a better way of installing the driver?

A better way to do this would be to let Ubuntu try to find the drive automatically. This is butter because Ubuntu will be able to find a .deb with the driver already compiled. The downside is that you will need to attach your computer to the Internet with by Ethernet for this to work. You didn't say what sort of computer you are having the problem on, but you should be able to get on-line with an Ethernet cable connected to the router and the computer with Ubuntu. Once you are on-line, in Ubuntu you can go to Additional Drivers program and search for unsupported hardware. Additional Drivers will download and install the missing drivers if there is one available form Ubuntu. This can walk you though using Additional Drivers.


No solution but a workaround. Found out that Owncloud client does the job. Nextcloud is a fork of Owncloud and for the actual version from Ubuntu Software Center (12.0.4 on Ubuntu 17.10) owncloud client has no problem syncing with Nextcloud server. Strange, but for now it is ok, I think in further versions it will might be different, as Nextcloud development seems to be faster. So, finally Owncloud client shows up all available folders and partitions, Nextcloud client doesn't, for example /media is not there for some unknown reason.


You can make Flash Player work in Fogger by executing following commands in Terminal:

cd ~; mkdir foggerflashfix; cd foggerflashfix
wget https://fpdownload.adobe.com/get/flashplayer/pdc/11.2.202.491/install_flash_player_11_linux.i386.tar.gz
tar -zxvf install_flash_player_11_linux.i386.tar.gz
sudo mkdir /usr/lib/flashplugin-installer/i386
sudo cp libflashplayer.so /usr/lib/flashplugin-installer/i386
sudo apt-get install nspluginwrapper
sudo nspluginwrapper -i /usr/lib/flashplugin-installer/i386/libflashplayer.so
sudo nspluginwrapper -v -a -n -i
cd ~; rm -r foggerflashfix
exit

After that, your Flash content should load correctly.

Source


I can't install Ubuntu 18.4 in my laptop

This sounds like an installation media issue. Try to create a new boot disk with a new iso.
Also since you are doing this on a separate drive you can remove the original one to make sure it doesn't get formated during installation. This isn't absolutely necessary just an easy precaution. Then you can just refresh the grub menu to find the other os.

Worst case scenario you can try to install Linux onto your drive on a different computer and then plug it into your laptop afterwards.


Clean (NO WATER!) or Replace your keyboard. Is anything stuck under/around the / key? This is hardware, not software.


I was playing around with making web app like I used to do with prism.

I just read about fogger today.  I installed by downloading the deb for latest version.  I installed with gbebi.  But had to run sudo apt install -f after that to get completely installed.

It is also possible to create a .desktop file and have it execute

webbrowser-app --chromeless --maximized http://www.yoursite-url.com

If you want to be able to mouse-up on bottom of window for path... back... etc, remove --chromeless from execute line.

The "chrome" of this app only displays temporarily so the chromeless aspect is likely not necessary for the most part.


steps to run the cuda sample program for vector addition?

Open the terminal and type:

gedit ~/.bashrc

This will open .bashrc for editing. Add the following to the end of your .bashrc file.

export PATH="$PATH:/usr/local/cuda-8.0/bin"

This sets your PATH variable to the existing PATH plus what you add to the end.

Run source ~/.bashrc when in the home directory to reload the configuration for your session.

Then type nvcc to run it.


Partial (specific releases) mirror of Ubuntu Archive via rsync only

if you can install anything on the machine you are USING to transfer, try dpkg-repack, it will put all of the applications into .deb files that you can install on site on any debian based system

on the transfer machine, run these commands

$ sudo apt-get install dpkg-repack fakeroot
$ mkdir ~/dpkg-repack; cd ~/dpkg-repack
$ fakeroot -u dpkg-repack `dpkg --get-selections | grep install | cut -f1

then on the target machine(s) run this

sudo dpkg -i *.deb


I Installed Ubuntu 14.04 and On The First Load I Get No Desktop Just a Background and Cursor

You can try the fglrx installation with these steps:

Remove/purge current fglrx and fglrx-amdcccle (If you have used a method outside of aptitude, apt, Software Center or Synaptic, follow the other party's instructions for removal). You will need to deliberately remove both the normal and -updates versions in recent releases of Ubuntu because it seems that attempting to remove one installs the other:

sudo apt-get remove --purge fglrx*

Reboot.
You may need to install the linux generic headers

sudo apt-get install linux-headers-generic

Install the driver

4.1. For 12.04:

sudo apt-get install fglrx fglrx-amdcccle

or

sudo apt-get install fglrx-updates fglrx-amdcccle-updates

4.2. From 14.04 forward, fglrx-amdcccle is included when you install fglrx, so the following will suffice:

sudo apt-get install fglrx

or

sudo apt-get install fglrx-updates

To install the packages for hardware acceleration along with the driver:

sudo apt-get install fglrx xvba-va-driver libva-glx1 libva-egl1 vainfo

or

sudo apt-get install fglrx-updates xvba-va-driver libva-glx1 libva-egl1 vainfo

Generate a fresh xorg.conf BEFORE REBOOTING!

sudo amdconfig --initial

If you are using multiple AMD graphics cards or AMD dual graphics (i.e.: notebook users), use:

sudo amdconfig --adapter=all --initial

Reboot again.
To confirm the drivers are working open a terminal and type:

fglrxinfo

You should get an output similar to the following:

fglrxinfo
display: :0  screen: 0
OpenGL vendor string: Advanced Micro Devices, Inc.
OpenGL renderer string: AMD Radeon HD 6300M Series
OpenGL version string: 4.2.11733 Compatibility Profile Context

Source: https://help.ubuntu.com/community/BinaryDriverHowto/AMD


flatpak and kde (Kexi) problem: app/org.kde.kexi/i386/master not installed

problem solved. I could start kexi in GUI.


WUBI is not supported with 13.04 and the newer versions. It's also not available with UEFI or windows 8. More here: http://www.ubuntu.com/download/desktop/install-ubuntu-with-windows


How can I create help tags for vim plugins from packages?

I was able to solve the problem in two steps.

Since vim had not been able to generate the required index from the compressed documentation, I extracted these files before re-running the indexer. As vim is able to deal with compressed documentation, I removed the extracted documents and adjusted the filenames of the index accordingly.

#!/bin/bash

#set -x
set -e

umask 077
TMPTAGS=$(mktemp --tmpdir "`basename "$0"`.XXXXXXXXXXXX")
trap "rm -f '$TMPTAGS'" EXIT

declare -r AWK_SCRIPT='{ if( $2 in files ) $2=$2".gz"; print }'

helptags(){
        # extract zipped helpfiles and remember filenames
        local -i I=0
        local -a TXT
        for ZIP in `find . -xtype f \( -name '*.txt.gz' -o -name '*.??x.gz' \)`; do
                T=${ZIP%.gz}
                if [ -n "$T" ]; then
                        TXT[$((I++))]=$T
                        zcat "$ZIP" >"$T"
                fi
        done
        # generate tagfiles
        vim -c 'helptags .' +q
        # point tags to the zipped helpfiles
        local AWK_BEGIN="BEGIN { OFS=FS; "
        while [ $((I--)) -gt 0 ]; do
                AWK_BEGIN+="files[\"`basename "${TXT[$I]}"`\"]; "
        done
        AWK_BEGIN+='}'
        for T in `find . -xtype f \( -name 'tags' -o -name 'tags-??' \)`; do
                awk -F '\t' "$AWK_BEGIN $AWK_SCRIPT" "$T" >"$TMPTAGS"
                mv -f "$TMPTAGS" "$T"
        done
        # remove unzipped helpfiles
        for T in "${TXT[@]}"; do
                rm -f "$T"
        done
}

while [ $# -gt 0 ]; do
        if [ -d "$1" ]; then
                pushd "$1" >/dev/null
                helptags
                popd >/dev/null
        else
                printf '*** Invalid argument: %s\n' "$1" >&2
        fi
        shift
done

Finally, I have appended /usr/share/vim/addons to the runtimpath variables in /usr/share/vim/vim74/debian.vim and /etc/vim/vimrc.tiny.


I was actually missing some entries to iptables, added as follows:

# iptables -t nat -A POSTROUTING -o enp0s3 -j MASQUERADE
# iptables -A FORWARD -i enp0s8 -o enp0s3 -m state --state RELATED,ESTABLISHED -j ACCEPT
# iptables -A FORWARD -i enp0s8 -o enp0s3 -j ACCEPT

with enp0s8 the interface to the outer world, and enp0s3 the interface to the Internal network.

Requests to the Internet from VM2 are now working... :)


All I needed is to reboot after install the compiz extras, now it works fine and now I have a simplier app switcher working.


The script that you found is flawed with parsing output of ls command (you can read about why you shouldn't use ls in scripting here).

A better approach is to use find command and pipe its output to xargs.

Since in the original script you operate on the files that are in a specific directory, I've tailored the command accordingly. Navigate to the directory where you want to hide the files and run the part bellow:

find . -maxdepth 1 -type f ! -name  ".*" -printf "%f\0" | xargs -0 -I file mv file .file

Here is a small demo in my home directory. I create 3 files and use above command to hide them.

$ touch file1 file2 file3

$ find . -maxdepth 1 -type f ! -name  ".*" -printf "%f\0" | xargs -0 -I file mv file .file

$ ls -a
./             .bash_logout  Desktop/    .file1   .gnupg/        .macromedia/  Pictures/  .ssh/        .xsession-errors
../            .bashrc       .dmrc       .file2   .ICEauthority  .mkshrc       .profile   Templates/   .xsession-errors.old
.adobe/        .cache/       Documents/  .file3   .lesshst       .mozilla/     .psensor/  Videos/
.bash_history  .config/      Downloads/  .gconf/  .local/        Music/        Public/    .Xauthority

The above works for files. To make it work for directories, simply change -type f to -type d.

Demo:

$ ls
dirone/  dirthree/  dirtwo/

$ find . -maxdepth 1 -type d ! -name  ".*" -printf "%f\0" | xargs -0 -I file mv file .file

$ ls

$ ls -a
./  ../  .dirone/  .dirthree/  .dirtwo/


Uninstalled running kernel. Machine still up, but afraid to reboot

Most likely, it will be fine to ((optionally) utter a small supplication and) reboot. As suggested in a comment by Katu, most likely there was an update since you last booted, and that's why you're not using the latest kernel.

However, I'd strongly recommend you reinstall the running kernel:

sudo apt install linux-image-$(uname -r)

And reinstall the 91 kernel to ensure it is complete:

sudo apt install --reinstall linux-image-4.4.0-91-generic

Running either of these commands will trigger an update-grub and regeneration of the initramfs, configuring the system to boot from the latest possible kernel installed.

It's advisable to have an extra kernel, just in case of any issues.

Next time you want to clean up, please use sudo apt autoremove which cleanly removes all but the latest two kernels, and next time you install Ubuntu, consider not making a separate /boot partition :)


This may take more troubleshooting

Try the following to reset the password:

Reboot the computer, press quickly esc or shift to get a boot menu. Select the recovery mode (something like

Ubuntu, kernel 2.6.17-10-generic (recovery mode)

in the menu.

Open up a terminal, type

passwd username

Then follow the steps to reset password
I hope this works


Why is XPS 13 not able to run at maximum CPU-Speed?

I had the same problem, but I remembered having set up silent_mode/eco_mode  in dualboot Windows which had been hibernated before booting Ubuntu.
Rebooted to Windows, turned off silent_mode/eco_mode, rebooted to Ubuntu -- 2.7GHz again.

May be a coincidence, but just rebooting with external power plugged in helped.


/boot partition is your partition with kernels and grub loader. Actually no needs to increase it, just clean old kernels from time to time. https://askubuntu.com/a/254585/217142

PS. You can increase it but from Live CD or like that.


Manually re-installing the newest kernel via sudo apt install linux-generic-hwe-16.04 like it is recommended in kernel-4-10-in-ubuntu-16-04-3-update solved the problem.


pgadmin4 1.3 install Error loading script - /sqleditor/sqleditor

You need to deactivate the virtualenv and create a new one.

 $  deactivate

In doing that you need to re-run setup.py:

If the path to v1.3 is different then make sure to change PGADMIN4_SRC to point to new location.
Create a new web/config_local.py with the values you want.

Create the new venv

$ mkvirtualenv pgadmin4
and/or
$ workon pgadmin4

Then run

 $ python  $PGADMIN4_SRC/web/setup.py

Then you can start

 $ python  $PGADMIN4_SRC/web/pgAdmin4.py

The sqleditor/sqleditor error should no longer appear.


There is no xenial entry in http://ppa.launchpad.net/tualatrix/ppa/ubuntu/dists/ for which snapcraft would fail since apt updating will not be entirely successful.

For your problems to go away, run:

add-apt-repository -r ppa:tualatrix


for USB printers your snap can use the raw-usb interface to gain access to /dev/usb/lp0 ... if you use an x86 based architecture you also have the printing-stack-snap (only available for x86 for some reason) that can give you a full cups stack on core.


how to change setting for automatic shut down?

There are several reasons for a computer to shutdown, and I can quickly identify 4:

There is a process (or cron job) shutting it down;
Power outage, abnormal shutdown;
Power outage, gracefull shutdown by your UPS;
Hardware failure.

You can see the reason for the shutdown with this command:

sudo last -x

This command is used to list all system loggins, but it also displays the shutdown, reboot and boot times.

When you shutdown your computer, the run level changes to zero, so you should see this line:

runlevel (to lvl 0)

If you don't see it, then it's an abnormal shutdown (power outage), and that means you should install an UPS.


Where should I place my sqlite database for proper packaging?

If the database stores user-settings, it should go into ~/.config/<app>/.  If you want to ship a copy with the default settings, that should go into /opt/ with your other files, and get copied into ~/.config/<app>/ the first time the user runs your app.

/etc/ should only be used for storing system-wide settings, not user settings or defaults.


With single awk command:

awk '{cmd="host "$0; cmd|getline $0; print $1,$NF;close(cmd)}' infile

Explanation:

Here we set a shell command as host $0 and assign to a variable called cmd. Then with cmd |getline $0 we call that command Using getline from a Pipe which awk passes the line from input infile file to the cmd, then print the first and last fields (domain& IP). At the end we need to close the command we opened, so we used close(cmd) to close it.

Input:

askubuntu.com
stackexchange.com

Result:

askubuntu.com 11.22.33.44
stackexchange.com 55.66.77.88


How to recover data lost when connecting a USB drive to a VirtualBox VM

Please consult this help page for information regarding data recovery on failed or formatted drives from within ubuntu. It is possible to recover lost data but it is worth you reading the help page to avoid me repeating it here.  Tread carefully, and if in doubt take it to a store that offers data recovery.


How do I permanently change permissions for /dev/ttyS0?

There's no need to change system file's permissions. The serial devices have the following default permissions:

crw-rw---- 1 root dialout ... /dev/ttyS0

So all you have to do is add the user to the dialout group:

sudo adduser $USER dialout


The One right way to install python3 is

sudo apt-get install python3

or

sudo apt install python3

Whether you use apt or apt-get doesn't matter in this case; it is just a personal habit. apt is a front-end for apt-get but for this command there's no difference, so both are fine.

Once installed you have the new command python3.

Python is somehow special in that there are two major versions: python2 and python3. When you install or update (or call) python you'll get the python2 line.

Some time ago the Python developers decided to release a completely new version of Python with new features and new syntax. To not break existing programs, this new version is called python3. So it's completely safe (and usual) to have both python (V2) and python3 installed at the same time. Some of your existing programs will use python (V2) and some of them will use python3. The majority will currently use python (V2) (because they aren't rewritten yet to comply with python3's syntax), so do NOT uninstall python (V2).

See also How can I remove python 2.7 after installing python 3.3?. The question is five years old but still valid. The outcome is don't!


How do I boot directly into a user's xterm?

So, you do not mean an xterm, but a command prompt without a GUI ?

Should work like that:
Possible to install ubuntu-desktop and then boot to no GUI


I have also noticed Ubuntu WiFi drivers in general are too often not properly tuned to play nicely with random wifi router hardware and so drop off connections or fail to connect especially at questionable public wifi locations like libraries ... sadly I resort to using my cell phone as a wifi hotspot to band aid the situation, not a sustainable solution especially at home

Luckily at home you have control over your router ... I suggest you view your wifi landscape and move your router channel onto the quietest possible  ... on android the free app: Wifi Analyzer will give you plots like this

where the red network called gone fishing is mine and its not competing with noisy neighbors ... if above landscape matches yours the the below suggestion will not help your situation ... whereas the following wifi landscape also shown using above mentioned app shows my network thefloat which may well benefit from moving the router channel from current 6 to channel 8

All routers allow you to login to the router and change settings like its output frequency channel.  Google your router make/model ... typically its address is something like    http://192.168.1.1/   believe it or not a typical router login could be :    YMMV

    login :   leave blank
    paswd :   admin

rummage around to change the channel setting .... Alternatively you can always solve this bad wifi driver issue by skipping the wifi and plug in an ethernet cable from your laptop to the router ;-)


Cannot install Ubuntu 20.04 along with Windows 8

It looks like your HDD is dead. So you need to replace it first.


looking for a Gnome panel applet which can open and close the dvd/cd tray

I do not know any applet capable of triggering the cd tray, but you can add a custom launcher as applet.

Choose "Custom Application Launcher" from the "Add to Panel" menu.
Set "Type:" to "Application in Terminal"
Choose a name.
Write eject -T in the "Command" field.
Click OK and try it.

This should work, but I could not test it, since I do not have a cd drive.

For detailed information about this command, type man eject in a terminal.


Ubuntu 12.10 Macbook Pro Install Problems

Follow instruction here

You need to install the cutter application, use that to unpack the proper firmware.  Then you use modprobe -r to remove all the drivers... then modprobe to load the driver you want.  I've used the STA, B43, & wl.

The link I posed is very descriptive, read it carefully and follow the steps based on your outputs... good luck.


Is there a keyboard command for 'show desktop'?

By default, it's set to Ctrl+Alt+D. You can set your own shortcut by going to System → Settings → Keyboard Shortcuts and changing "Hide all normal windows and set focus to the desktop" located under "window management":


How to change the signature color in thunderbird?

You can edit the signature in HTML by ticking the "use HTML" checkbox in the Signature Text box.

Then in the signature box type something like

Richard Holloway

Or

RICHARD


You are using an older version of Compiz with Newer Xubuntu. The latest version of compiz is 1:0.9.12.2 where you installed 0.8. I don't know how you installed that version.

Xubuntu works fine with Compiz latest. But you have to enable some plugins after first use. To tweak plugins, I highly recommend ccsm.

Install it with

sudo apt install compizconfig-settings-manager

I also recommend upgrading compiz. This will do it.

sudo apt install compiz

Now open it using ccsm command in app finder or searching it in menu.

Enable these plugins

Composite
OpenGL
Animations
Window Decoration (it will enable the buttons and title for windows)
Maximumize
Move Window (This will enable you to move window with mouse)
Scale (If you like it)
Place windows
Application Switcher (to use alt-tab window switching)

You can also enable other plugins as well. But above are necessary

I also recommend changing the theme. From its DeviantArt page, I saw the theme is very outdated and only has gtk-2.0 themeing. They don't even include gtk-3.0 theme.

If you like xosemite, you'd like macbuntu theme. Install these instead of that one. You can get the installation instruction here

https://launchpad.net/~noobslab/+archive/ubuntu/macbuntu


Use Pictures for an Image object in QML for Ubuntu Touch

I'm afraid you can't: your application is confined, and cannot access any files under the ~/Pictures directory.
More info about this topic at https://developer.ubuntu.com/en/apps/platform/guides/app-confinement/


Create a bootable usb in a mac for a non-mac system

I believe that the article that you want is: http://www.ubuntu.com/download/desktop/create-a-usb-stick-on-mac-osx

But in case you do not want to look it up, here it is:

Note: this procedure requires that you create an .img file from the .iso file you download. It will also change the filesystem that is on the USB stick to make it bootable, so backup all data before continuing.

Tip: Drag and drop a file from Finder to Terminal to 'paste' the full path without risking typing errors.

Download Ubuntu Desktop
Open the Terminal (in /Applications/Utilities/ or query Terminal in Spotlight).
Convert the .iso file to .img using the convert option of hdiutil.  Example:

hdiutil convert -format UDRW -o ~/path/to/target.img ~/path/to/ubuntu.iso

Note: OS X tends to put the .dmg ending on the output file automatically.
Run diskutil list to get the current list of devices.
Insert your flash media.
Run diskutil list again and determine the device node assigned to your flash media (e.g. /dev/disk2).
Run diskutil unmountDisk /dev/diskN (replace N with the disk number from the last command; in the previous example, N would be 2).
Execute sudo dd if=/path/to/downloaded.img of=/dev/rdiskN bs=1m (replace /path/to/downloaded.img with the path where the image file is located; for example, ./ubuntu.imgor ./ubuntu.dmg).

Using /dev/rdisk instead of /dev/disk may be faster.  If you see the error dd: Invalid number '1m', you are using GNU dd. Use the same command but replace bs=1m with bs=1M.

If you see the error dd: /dev/diskN: Resource busy, make sure the disk is not in use. Start the 'Disk Utility.app' and unmount (don't eject) the drive.
Run diskutil eject /dev/diskN and remove your flash media when the command completes.


Making one certain key STICKY and another one into TOGGLING key

Changing Fn may not possible only if the its manufacturer added such option
to BIOS.

Why?
Short answer: Pressing Fn alone does not send a scancode.
Long answer: See How do Fn keys work?
Stiky key for Caps lock alone (not full accessibility sticky modifiers)

Change Caps lock key interpretation

sudo nano /usr/share/X11/xkb/compat/caps

Change LockMods action to LatchMods

partial xkb_compatibility "caps_lock"  {
    // Keysym Caps_Lock locks Lock modifier.
    // With this, the keysym Caps_Lock can be used without binding the whole
    // key to a real modifier.
        // This is essential when you don't want to use caps lock on the first
        // level.
        // This should not have any compatibility issues when used together with
        // other layouts which don't utilize this capability.
    interpret Caps_Lock {
        action = LatchMods(modifiers = Lock);
    };
};

Compile the change & update the initramfs images

sudo dpkg-reconfigure xkb-data
sudo update-initramfs -u -k all

Reboot

Note, I still don't know how to make keyboard led follow the state.

To make toggle for other modifiers (ex Alt) change their SetMods action to LockMods. Most virtual modifiers are handled in compat/misc file.

For references see my answer to other similar question: Letting modifier keys act as toggles under X


Cannot access the file: Permission denied - Virtualbox

There is no /var/log/vbox-install.log, it was not created. The error when you tried to install the kernel module states that it couldn't create that file because it lacked permissions.

Please to run a program as root use sudo, in your case you need to type:

sudo /etc/init.d/vboxdrv setup

If there is any problem with it you can read the log with the command:

gedit /var/log/vbox-install.log

No need to be root just to read it.


I quickly found out that it couldnt find some headers because i didnt properly copied them (silly me).

But it didnt solve the linking problem. I managed to solve that with manually compiling opencv for every architecture and inlcuding the library files in the project, following this project as a reference:
https://github.com/nikwen/ubuntu-tox-client


Dual Boot after unique installations [Ubuntu 18.04.2 and Windows 7]

For those who will try this answer with newer computers, make sure both Windows and Ubuntu are installed in either UEFI mode or both in Legacy BIOS mode. If Windows boots in UEFI mode (the default for computers with pre-installed WIndows) and Ubuntu boots in Legacy BIOS mode (or vice versa) then you won't be able to switch between the two OSes without going into UEFI setup and switching the boot mode every time.
Reconnect the SSD containing Windows to the computer
BIOS(or UEFI for newer computers) setup
Get into BIOS setup when the computer boots by pressing the BIOS setup key.
Make the the SSD with Ubuntu the first disk to boot from.
Save the changes and continue booting.
After Booting Ubuntu
On first boot, you may or may not see the GRUB menu. If this happens you will directly boot Ubuntu. This is normal. After Ubuntu boots login using the username and password you selected during Ubuntu installation.
Open a terminal by pressing Ctrl+Alt+T together. Then enter:
sudo update-grubEnter↵
You will be prompted for your password. When you enter the password in the terminal the cursor will not move, there will be no dots or ****. this is normal. Press Enter↵ after password.
The above command will look through all the drives and discover that you have Windows 7 (and possibly recovery partitions) in Disk 1 and add these to the GRUB menu in Disk 2. It will not change anything in Disk 1.
In the next reboot, you will see the GRUB menu, something like:

Yours will look slightly different. If you do nothing after a few seconds the computer will boot Ubuntu.

You can press Enter to boot Ubuntu right away.
To boot Windows, use the down arrow key ↓ to select Windows
7 and press Enter↵.

Hope this helps


How to set one queuing discipline for two network interfaces

You can achieve this using a Raspberry Pi 4 and OpenWrt bundled with LUCI web interface.
If you have the Linux skills you can compile and build your OpenWrt image using the OpenWrt images.  Others have compiled an image where you have everything you need to run the Raspberry Pi4 as a router, using LUCI to configure and implement firewall and SQM etc.
I used this for a couple of days with ZERO impact on network speed.
I hooked up the eth0 onboard Ethernet to the LAN side so it had a static IP address, and a USB3 Ethernet converter (Allowing me 1 Gbps) eth1 to WAN using DHCP.  This replaces your notebook and is therefore in series with your router and ISP.
Here is the link to the OpenWrt project website: https://openwrt.org/
Here is a link to the most up to date OpenWrt with LUCI image that I could find at the time of this writing (2021-04-17): https://github.com/wulfy23/rpi4
And here is the git clone URL: https://github.com/wulfy23/rpi4.git
Here is a walkthrough to get your RPi4 set up: (use the image from wulfy23 instead though) https://www.instructables.com/Highspeed-VPN-Router-With-Raspberry-Pi/
I just found an awesome video describing how to compile your own version of OpenWrt: https://www.youtube.com/watch?v=_MFkbcNFIqo


Ubuntu 14.04 Black Screen after login - Tried Everything

Step 1 : Remove all NVIDIA software you have installed.

Highlight the Ubuntu menu entry and  press the E key.
Add nouveau.modeset=0 to the end of the linux line.
Press the F10 key to boot into the Ubuntu system.

When the login screen appears press Ctrl+Alt+F1.
Enter your user name and the password, then execute :

sudo apt-get purge nvidia*
sudo reboot

Step 2 : Install NVIDIA drivers 352 from the repositories.

Highlight the Ubuntu menu entry and  press the E key.
Add nouveau.modeset=0 to the end of the linux line.
Press the F10 key to boot into the Ubuntu system.

When the login screen appears press Ctrl+Alt+F1.
Enter your user name and the password then execute :

sudo apt-get update
sudo apt-get install nvidia-352
sudo reboot


How do I fix a "Unknown configuration key `foreign-architecture' found in your `dpkg' configuration files." error?

You say in the comments that you see:

$ ls /etc/dpkg/dpkg.cfg.d/
multiarch

Presumably that file, /etc/dpkg/dpkg.cfg.d/multiarch, contains a foreign-architecture key. So I suggest just deleting the file:

sudo rm /etc/dpkg/dpkg.cfg.d/multiarch


Ubuntu VM fails to boot and blocks at "installing open-vm-tools"

Same problem, I solved removing SCSI disk and creating a new one in SATA mode.


Why do Ethernet devices not show up in "/dev"?

It's a good question. The reason is essentially historical; different groups with different goals and priorities added pieces of Unix over time, and the differences among various APIs are a reflection of this history.  I think the original device file concept goes back to Bell Labs, whereas network sockets were added later at UC Berkeley. Bell was trying to create a nice clean maintainable paradigm for AT&T's operations, whereas Berkeley needed to add internet features that didn't fit easily into that paradigm. Technically it would be possible to go back and create a /dev/eth0 file today (see below), but it would involve rewriting a prohibitive amount of legacy code.

Slight OT: If the subject interests you, consider taking a look at Plan 9, which took "everything is a file" to greater extremes (just don't expect it to have very many modern, usable applications):

http://www.faqs.org/docs/artu/plan9.html

  many facilities that under Unix are accessed through various ad-hoc interfaces like BSD sockets, fcntl(2), and ioctl(2) are in Plan 9 accessed through ordinary read and write operations on special files analogous to device files


Can't detect wireless connections with an Atheros AR2413 on an Acer Aspire 3630

You should be able to add those commands listed in your update, to /etc/rc.local to have them run at start up.


I don't necessarily agree with their reasons for claiming you should avoid .htaccess files.  Their reasons are:

Reason 1 is performance - Apache needs to scan directories and read and parse the .htaccess files at run time.  This isn't a huge burden and caches well.

Reason 2 is security. You're allowing users to modify Apache's configuration.  But they're only modifying its local configuration for that particular directory, and it's possible to specify in Apache's global configuration which directives they are and aren't allowed to modify.  Plus, if users having access to edit .htaccess files is a security problem for you, then surely also allowing the same users to use .php files is an even bigger security problem.

There's still some benefits to using .htaccess.  It's somewhat of a de facto standard now so much so that you can pretty much depend on being able to use it on shared hosting, and many web application software packages make use of them in their own software.  And it means that local Apache configuration is kept with the application it's configuring which might be good for backups, version control etc.
Anyway, whether you want to heed this advice is up to you.
If you do want to move to using Apache's global configuration, you can do as in your example.
However, the global apache2.conf file can be somewhat of a mess, and it was installed by the Apache2 package itself.  For a more portable solution, put your rules into individual config files:

Apache2 reads all config files in /etc/apache2/conf.d/.  This can be good for any general configuration directives you want to add that don't relate to any particular virtual host.  Just add a new file there and put config into it.

Apache2 stores config files for each virtual host in /etc/apache2/sites-available/.  That is a suggested place for putting in configuration for each virtual host, in separate files.  Then, enable and disable these virtual hosts with a2ensite and a2dissite.
Assuming that these configuration directives apply specifically apply to a certain virtual host I'd choose the latter - put it in where-ever you've put the configuration for that virtual host (which I'd recommend placing in /etc/apache2/sites-available/.


X11 connection rejected because of wrong authentication when using sudo

Found an answer here: https://www.slothparadise.com/sudo-root-x11-connection-rejected-wrong-authentication/
For whatever reason, Xauthority isn't being passed over on sudo. But... sudo xauth merge ~/.Xauthority then sudo graphical-app works fine.
I think this is unrelated to ssh, just to Xauth and sudo.


How to make process "terminable" only by SIGHUP or SIGKILL?

Probably the simplest way would be to write a minimal bash script, using the builtin trap to specify a custom signal handler:

#!/bin/bash

function mysighandler {
  printf 'ignoring TERM signal\n'
}

trap mysighandler SIGTERM

while :
do
  printf 'Running. . .\n'
  sleep 2
done

You could set the handler to the null string, which would cause the signal to be ignored silently - but creating a minimal handler allows you to confirm that it's been intercepted.

Alternatively, write a small C program that uses the signal API - see man 2 signal.


How to install Avro Keyboard in Ubuntu 20.04

Avro Keyboard - Ubuntu: 20.04
Installation:
Press Alt+Ctrl+T to start terminal and run following command

sudo apt install ibus-avro

Restart system or Log out - Log in
Go to Settings > Region & Language
In Input Sources click +
Click Bangla or Bangla (Bangladesh)
Finally select Bangla (Avro Phonetic)
Now it should work just fine.
If not make sure your Keyboard Input Method System is > IBus
Common Problem
Avro Stops writing Bangla. Try to restart ibus.

ibus restart


Share files between Mac OSX and Ubuntu on Dual boot

Depending on your needs you should try the NTFS1 and ExFAT2 file systems. They're both well supported in Linux and OS X3 (with FUSE on both ends) and don't suffer from the problematic limitations of the FAT family.

If you need help formatting your partition with either of them, give me a comment and I'll look for or write some instructions. You should be fine with the usual tools (mkfs, Gnome Disks, GParted), though.

1 NTFS works out of the box on Ubuntu.

2 Install exfat-fuse to give Ubuntu the ability to mount ExFAT file systems and exfat-utils to create and manipulate ExFAT file systems.

3 For instructions on how to use FUSE to mount NTFS and ExFAT file systems on OS X please refer to our sister site AskDifferent or other online resources as they would be off topic here.


Ubuntu and Windows 8 Boot problems (SSD uefi)

GRUB was loading on your computer; it just wasn't presenting a menu because it believed there were no options available. As I understand it, you're now back to something that's virtually identical to your original state -- you can boot Linux but not Windows. The only difference is that now you've got a GRUB boot menu. If I've misunderstood, please clarify.

Unfortunately, booting Windows is not GRUB's strong point. There are numerous suggested GRUB configurations available online, but they often fail -- what works on one system fails on another. The one I've got offhand is this:

menuentry "Windows 8" {
    insmod part_gpt
    insmod chain
    set root='(hd0,gpt1)'
    chainloader /EFI/Microsoft/Boot/bootmgfw.efi
}

You'd need to enter this into /etc/grub.d/40_custom and then run sudo update-grub to make it available. Note that you may need to change the set root= line and/or the chainloader line for your boot loader. Because you've run Boot Repair, the chainloader line needs to reference the Windows boot loader's new filename (probably bkpbootmgfw.efi).

Another option is to install my rEFInd boot manager, which tends to be more reliable at launching Windows. Unfortunately, the fact that you've run Boot Repair complicates this, because Boot Repair moves and renames the Windows boot loader and copies GRUB into the old Windows boot loader location. Thus, you may need to change this back, either manually or by re-running Boot Repair and selecting options to undo its changes.

With either solution, you may need to either disable Secure Boot in your firmware or install an updated version of shim. The former is likely to be much easier, but I can't say precisely how to do it because it varies from one EFI to another. The latter option is trickier and is complex. See the rEFInd shim documentation for details on how to do it with rEFInd.


You should reinstall your graphic card driver. Recently I've upgraded a computer with Ubuntu 14.04 to 16.04 that was using Nvidia graphic card driver supplied by Nvidia website (not from official ubuntu's repo). It just crashed like you reported. I fixed this by overriding the driver by the supplied in Ubuntu's repositories. I just make shure that I was using the same version available to my graphic card in nvidia download page.

Following images can illustrate the process.

Finding by apropriate graphic card version

Getting the apropriate version number

In my case, i just typed

 # apt-get install nvidia-361

Obviously, accessing root shell in repair console, with network enabled and rw access to / partition.


It's possible that TestDisk will recover the partition on the disk. If not, you may need to resort to PhotoRec, which is a file-level recovery tool. The trouble with PhotoRec is that it doesn't typically recover filenames or directory structures, so you can end up spending dozens of hours sorting through and renaming/moving files that it recovers.

As to the cause, it's impossible to know. Some possibilities that spring to mind include:

Random data corruption caused by bugs, cosmic rays (for real), a power surge, a bad cable, or whatever.
A physically damaged disk. Checking it with a SMART utility (like GSMartControl) is advisable.
The uncontrolled shutdown you describe may have caused data corruption because a cache wasn't written back to disk.
Somebody may have broken into your computer and maliciously done damage. (Similarly, a virus or worm might be responsible, especially if the computer dual-boots with Windows.)

No doubt I'm forgetting some possibilities, too. You can perform checks like a SMART test, tests on your cables, security screenings, etc., to look for some of these items. Others, if they're the cause, will likely remain mysteries forever.


Oracle Virtualbox does not open since upgrade

First Remove Completely Virtualbox.

sudo apt-get purge virtualbox-4.2

Remove other unnecessary packages.

sudo apt-get autoremove

Update packagelist.

sudo apt-get update

Reinstall Virtualbox

sudo apt-get install virtualbox-4.2


You can remove some files in /var/cache in order to get it running again.
In order to keep more space afterwards you can run:

sudo apt autoremove && sudo apt autoclean && sudo apt clean

in a console.


You cannot resize the /dev/sda4 partition, because it contains the mounted running system. What you're trying to do there is like having a surgeon operate on himself at home...  ;-)

You have to do the resizing action from a live media - boot from an Ubuntu installation media. Select Try Ubuntu without installing and once on the Live desktop environment open GParted.

Now you will find all partitions (except of swap eventually) unmounted and are able to resize partitions. In case the swap partition is mounted, right-click the partition and select 'swapoff'. This is the recommended and safe way to work on disks/partitions without damaging systems.

(Which would be the equivalent of going to the hospital and have the surgeon operate on you there)


Use browser's sing in to sync, both on windows and ubuntu. Your bookmarks will be synced, also history, logins, and so on.

This way applicable both for Firefox and Chrome but separate for each other.

There are software to access ext4 from windows, so you can copy files to ubuntu. I don't remember application name, but you can easy search for it. Bookmarks are not files, but records in browser profile, so use sync for them instead of copy.


Installing packages from the Ubuntu software center using snap have some issues.

  "snap", a new cross-OS package manager. Snap will be much better than APT one day, but right now it's in the beginning stages and experiencing growing pains.

I removed skype from the software center and I downloaded the .deb file from Official Skype website.

Then I installed it using dpkg which solved the problem.

Note: this answer inspired me.


Connect to MySQL on remote server from inside python script (DB API)

2 things i can think of, 1 beeing that the port is not open for your home, another would be that the user on the server was created for your office computer (user@office)

you can test the first with nc -vz host  port (default 3306)
second would be to query the mysql.user table and se how your user is defined

mysql> select user,host from mysql.user;


At this point, according to VeraCrypt documentation, only Windows operating systems are supported, and you cannot use Veracrypt to fully encrypt a Linux disk.


MAAS: Works with the GUI but the CLI says "409 CONFLICT"

If you have only 6 nodes and they are in the deployed state, then there are no more nodes to acquire, that's why you get the 409 error. You can only acquire ("allocate") nodes that are in the READY state.


Non english file names not shown or incorrectly on Kubuntu 20.04.2 LTS

You have set (probably via the KDE GUI) the cv_RU.UTF-8 locale which has not yet been generated. Fix that by running:
sudo locale-gen cv_RU


Systematic way of finding shortcut associations

I'm not sure if this is what you want, but you could do something like

gsettings list-recursively | grep keybindings | grep '\[.\+\]'

from the command line to, extract all the non-empty keybindings from the dconf database.


Nvidia Go5600 video, black screen after login after 12.04 > 14.04 upgrade

I had a desktop version of Ubuntu where I previously had the black screen problem. It was essentially resolved by aggressively removing all the nvidia files. My summary appears here: Fixing/Repairing a Blank (Black) Screen in Ubuntu 13.04. Another potentially useful thread: Problem with Nvidia driver 331.20 on Ubuntu 13.10 (64bit)  Whether the approaches outlined will work with a laptop are unknown to me.

You may also wish to review this Ask Ubuntu post: How can I uninstall a nvidia driver completely?


Install eclipse + eclim in a headless server

As you say you do not have root access, the following steps install everything to your home folder:
Download and install eclipse

Download eclipse here, eg. Eclipse IDE for Java EE Developers 64-bit.

Extract the archive, change the name of the archive if necessary
 tar xf eclipse-jee-mars-1-linux-gtk-x86_64.tar.gz -C ~

Install and run eclim

Install eclim with -Declipse.home="$HOME/eclipse"
Check the filename eclim_2.5.0.jar and replace it if necessary
 java -Dvim.files=$HOME/.vim -Declipse.home="$HOME/eclipse" -jar eclim_2.5.0.jar install

Run eclimd
 ./eclipse/eclimd -b

Partially taken from here


LXDE - Use desktop as folder doesn't work

Right click desktop → "Desktop Preferences" → "Advanced" Tab.

Check the box for "Show menus provided by window managers when desktop is clicked".

Click Close.

Right click desktop again and choose "System" → "Restart OpenBox".

Desktop icons/settings should restore.


The problem here is that you keep re-writing your output file each time through the loop. Try this:

#!/bin/bash

cp ../input/infile.fg_1 temp

while read line; do
   sed -i "/$line/,+3 d" temp
done < strings.txt

mv temp ../output/outfile.fg_1

The -i in the sed command ADDS each change to the temp file and then once all of the changes have been made, we move it to your output file. If you wanted to work directly on the output file then do this:

#!/bin/bash

cp ../input/infile.fg_1 ../output/outfile.fg_1

while read line; do
   sed -i "/$line/,+3 d" ../output/outfile.fg_1
done < strings.txt


How to install 4shared Desktop on Ubuntu 17.10?

4shared offers a Deb package, but not easy to found:

https://dc346.4shared.com/download/x3JqSRo1

Open your terminal and install the package:

# Download the package
wget https://dc346.4shared.com/download/x3JqSRo1 -O desktop4shared-all.deb

# Install the package
sudo apt install ./desktop4shared-all.deb

Source : How do I  install 4shared?


How do I login to Ubuntu directly using root account?

Root account is disabled in Ubuntu for login by default. You would have to change root password to login directly.

Personally i suggest you login to root through your sudo account with sudo -i


See here.

As far as I am concerned, it is where stuff goes if the RAM is full


Does the ,remove_hiberfile tag disable hibernate when I boot into Windows?

From what I understand, it deletes the hibernation file to allow mounting the ntfs drive. However, if I have hibernate enabled in Windows, will the hibernate file be generated again allowing me to hibernate?

Yes.

And if I disable "Mount at startup" (,noauto tag), will that only delete the hiberfil.sys file when I mount the drive by clicking it rather than doing it at every boot up?

Yes.

What's the disadvantage of this?

None.