what is the difference between the hosts and hosts.allow files?

The two are quite different in their functions.

/etc/hosts is used as a local DNS on your local apache instance or nginx as the case may be to mapped domain names to the ip address 127.0.*.*.

From "man hosts": hosts - static table lookup for hostnames. So when we request a domain
in our browser say "mydoman.com", our system checks in the /etc/hosts files to resolve
this "domain name" to an "IP address". If we have that entry in the "/etc/hosts" file
then the page content is served up from our machine files else it look out on the inter-
net to resolve that name.

/etc/host.allow and /etc/hosts.deny is used like an iptable to control access to the machine or network form external sources. Note that both iptables and host access can't be used simultaneously. Its your either using iptables host access control mechanism, or your using the access control library mechanism

Example hosts file entries are

#
# hosts.allow   This file describes the names of
#               the hosts that are allowed to use
#               the local INET services, as decided
#               by the '/usr/sbin/tcpd' server.
#
# Only allow connections within the virginia.edu
# domain.

ALL: .virginia.edu

#
# hosts.deny    This file describes the names of
#               the hosts that are *not* allowed
#               to use the local INET services, as
#               decided by the '/usr/sbin/tcpd'
#               server.
#
# deny all by default, only allowing hosts or
# domains listed in hosts.allow.

ALL: ALL

Sources:

man hosts, man hosts_access, virginia.edu


Is it possible to view exactly what a package will install and where?

You can find the package information at packages.ubuntu.com (e.g. tomcat6), including file lists and download link.


How to fix "error: unknown filesystem. grub rescue>

The following solved the issue for me, I have Windows 7 & Ubuntu 10.04. After running the following commands I don't need to run these every time and am able to boot both the OS normally:

set root=(hd0,6)
set prefix=(hd0,6)/boot/grub
insmod normal
normal

Now once you boot into Ubuntu, run the following two commands as well:

sudo update-grub
sudo grub-install /dev/sda

Note: /dev/sda is drive where you want your GRUB installed, it can be /dev/sdb or something else, but is usually /dev/sda

Take into consideration that the hd0 could be X (0,1,2..) depending on the order of disks and the 6 could be also different, it could be (hd0,gpt7), for example.


How to install a custom library written in C?

If you want to install the C-based CS50 fork of the Stanford Portable Library, you can install it by running these commands in a terminal (Ctrl+Alt+T):

# Install build dependencies and set up /usr/local/src for administrators.
sudo apt-get update && sudo apt-get install build-essential openjdk-7-jdk git
cd /usr/local/src && sudo chgrp sudo . && sudo chmod g+w,+t .

# Retrieve, configure, build, test, and install the library.
git clone git://github.com/cs50/spl.git && cd spl
make SHELL=/bin/bash
build/tests/TestStanfordCSLib
sudo make SHELL=/bin/bash install

SHELL=/bin/bash is required, at least for the make install step, because the Makefile uses a feature present in bash (brace expansion) but not present in Ubuntu's default /bin/sh (which is dash).

Running sudo make install instead of sudo make SHELL=/bin/bash install will produce the error:

cp: cannot stat ‘build/lib/{libcs.a,spl.jar}’: No such file or directory
Makefile:320: recipe for target 'install' failed

In the build instructions, which as of the time of this writing have not been updated with a procedure for Ubuntu, Fedora users are instructed to run sudo make install. That works on Fedora, but not Ubuntu, because Fedora's /bin/sh is provided by bash.

Once you have successfully built and installed the library using those steps, two new files will exist in /usr/local/lib: libcs.a and spl.jar. To use the library from C programs, link to libcs.a.

If you want to install The Stanford Portable Library for C++, you can do that by running these commands in a terminal (Ctrl+Alt+T):

# Install build dependencies and set up /usr/local/src for administrators.
sudo apt-get update && sudo apt-get install build-essential openjdk-7-jdk
cd /usr/local/src && sudo chgrp sudo . && sudo chmod g+w,+t .

# Retrieve, configure, build, and test the library.
wget https://cs.stanford.edu/people/eroberts/StanfordCPPLib/cpplib.zip
unzip cpplib.zip && cd cpplib
make
./TestStanfordCPPLib

This procedure worked for me, and the test executable ran successfully. See the contents of the README file in the cpplib archive for additional information. Often to build software from source there is a ./configure step before running make; the README clarifies that, to build this software, one simply runs make.

Assuming make succeeded, it created:

a statically linkable .a library file, lib/libStanfordCPPLib.a, which is probably what you will link into your programs
statically linkable object files in the obj subdirectory of cpplib

Besides linking against the .a file (as one might usually do), it appears one way to use the library is to link against these .o files with your programs. The contents of Makefile, particularly under # Test program, show how to do this.

The .a file appears to have all these .o files linked into it, though, so you should not have to use the individual .o files unless you prefer to do so or need to produce an especially small statically linked executable.

(If you need to build a shared library--i.e., an .so file--rather than a static one, I suggest editing your question to add information about that. I don't know how to build cpplib in this way, but others may be able to answer that.)


18.04 - Wifi Hotspot does not come up after reboot

A Wifi hotspot use the same device than you use it to go on internet with this computer; this network card have 2 mode :

receiver mode (default); this mode is compulsory if you want to download updates
transmitter mode (case of the hotspot)

I pretty sure you can't start your hotspot because Ubuntu is downloading updates or something like that, so the network card is already used. The fact you said this issue occured after a reboot increased the chance of automatic updates download.

Solution : You just have to wait a little so this operation can finish, and then, you will be able to start your Wifi hotspot


Qualcomm Atheros Device [168c:0042] (rev 31) Wi-Fi driver installation

With a working internet connection by ethernet, tethered or whatever means possible, please open a terminal and do:

sudo apt-get update
sudo apt-get install git
git clone https://github.com/kvalo/ath10k-firmware.git
sudo mkdir /lib/firmware/ath10k/QCA9377
sudo mkdir /lib/firmware/ath10k/QCA9377/hw1.0
cd ath10k-firmware/QCA9377/hw1.0
sudo cp *  /lib/firmware/ath10k/QCA9377/hw1.0
cd /lib/firmware/ath10k/QCA9377/hw1.0
sudo mv firmware-5.bin_WLAN.TF.1.0-00267-1  firmware-5.bin

Reboot and your wireless should be working.


mv files from one folder to another 40GB at a time

Create a compressed tar file of all the files you need to move, split the tar file into 40Gb size chunks and move those 1 at a time.  When done cat the files back to 1 large tar file and untar it.

An example:

create an archive

tar -zcvf file.tar.gz /directory/*

c create
z compress
v verbose
f use a file as a target

split them up

    split -b 40M file.tar.gz

(by default) it will create files starting with xaa, xab, xac of roughly 40Mb each.
Move them to the new place.
Recreate the file

 cat x* > file.tar.gz

and untar it ...

tar xvfz file.tar.gz .


Simple answer: do dpkg --purge php5-sybase.

Longer answer: Debian packages have split conffiles and the rest.  When you remove the package (and not purge) the conffiles (such as /etc/php5/conf.d/mssql.ini) remains in the place and php5 then tries to load non-existent library.  This was fixed in php5 5.4.0, but it will be fixed only in non-removed packages (obviously one cannot fix a bug in the package where only conffiles remain).


Why is vlc 2.x not upgraded to the PPA 3.x version after adding the corresponding PPA for the matching Ubuntu version?

I know this can be a bit confusing, you have to click on View package details to see the build status of the packages. There you will see that amd64, armhf and i386 architectures failed. You can drill down further and look at the build log why it failed, just start at the end of the file an work your way up.

I guess the problem is buried somewhere in here or even earlier:

/bin/bash: line 4: 31545 Segmentation fault      (core dumped) ./vlc-cache-gen `realpath ../modules`
Makefile:1634: recipe for target '../modules/plugins.dat' failed
make[4]: *** [../modules/plugins.dat] Error 139
make[4]: Leaving directory '/<<BUILDDIR>>/vlc-3.0.0~~git20170702+r70519+66~ubuntu17.04.1/bin'
Makefile:1520: recipe for target 'all-recursive' failed
make[3]: *** [all-recursive] Error 1
make[3]: Leaving directory '/<<BUILDDIR>>/vlc-3.0.0~~git20170702+r70519+66~ubuntu17.04.1'
Makefile:1405: recipe for target 'all' failed
make[2]: *** [all] Error 2
make[2]: Leaving directory '/<<BUILDDIR>>/vlc-3.0.0~~git20170702+r70519+66~ubuntu17.04.1'
dh_auto_build: make -j4 returned exit code 2
debian/rules:245: recipe for target 'override_dh_auto_build' failed
make[1]: *** [override_dh_auto_build] Error 2
make[1]: Leaving directory '/<<BUILDDIR>>/vlc-3.0.0~~git20170702+r70519+66~ubuntu17.04.1'
debian/rules:232: recipe for target 'build' failed
make: *** [build] Error 2
dpkg-buildpackage: error: debian/rules build gave error exit status 2
--------------------------------------------------------------------------------
Build finished at 20170702-1002

Finished
--------

E: Build failure (dpkg-buildpackage died)

You probably have read the description:

  This package archive contains daily builds made from the VLC
  development branch (a.k.a. the vlc.git master branch). This is meant
  for testing purpose.

  Beware that the builds are fully automated, and do not go through any
  quality assurance whatsoever. Functional regressions and build breaks
  occur frequently.

  DO NOT USE this archive if you are not prepared to cope with such
  problems.

  Please report build breakages to the Debian/Ubuntu multimedia team.
  The VideoLAN developers do not have access to the build system.

I'm not sure if the Team has been informed about this and I'm not sure how to bring this to their attention after reading https://wiki.ubuntu.com/MOTU/Teams/Media and https://wiki.debian.org/DebianMultimedia. I was able to find only this thread about VLC 3.0 in the archives of the Debian Mailing list for the past year. It's quite puzzling an time consuming from my point of view to track this down if you haven't been involved at this level before.


not working as writing 3rd and 4th level characters

There is a simple explanation: The symbols you want to be able to type (ellipsis, endash and emdash) are not present in the Norwegian (Macintosh) keyboard layout, neither with the original Norwegian symbols file nor with the file you picked from the github project. The lines from the no file you included in your question are not made use of in Norwegian (Macintosh).

One way to type those symbols is to add the basic Norwegian keyboard layout to your list of input sources and switch to that layout.


I would suggest you try to boot with the boot-option

nomodeset

instead of

quiet splash

in the grub menu.


Sound from both speakers and headphones. Bug with Soundcard?

http://ubuntuforums.org/showthread.php?t=806620

This is an alsa issue with hda intel soundchips. There is a fix for it in the link above.


Can I legally create proprietary software to be distributed for profit using Ubuntu?

Disclaimer: I am no lawyer or certified legal counsel and this is no legal advice. Please consult a lawyer if you need to be more certain than what I can offer.

Most of the pieces of software on which Ubuntu is based or which are distributed with Ubuntu or through Canonical's package repositories (excluding the partner repository) are subject to various open source licenses1. (I'll call all of these just “Ubuntu” subsequently.) This has multiple consequences.

What you may do with Ubuntu software

Ubuntu's licenses don't restrict how you use it as long as you don't publish it. This means that you can do whatever you want with it as long as you do it for your own use. This includes the sale of goods and services made or building new software with the help of Ubuntu.

(Of course you may not use Ubuntu to commit crimes or otherwise harm someone but this is unrelated to Ubuntu or its licenses and entirely related to you and the local laws.)

Distributing software built with Ubuntu

You may distribute your own works, e. g. software developed completely by yourself, under whatever terms you like.

If you'd like to distribute derived works, e. g.

modified versions of existing software or
software that rely on a particular programming library,

you need to abide by the terms of the license set by the original work. This is typically somewhere between

appropriate attribution of the original author(s) and
distribution of the entire source code and build scripts of the derived work along with its binary form.

There is no restriction against commercial, for-profit distribution of works derived from open-source software (according to its official definition by the Free Software Foundation).

What happens if you violate a license

Copyright violation is primarily a matter of civil law and does not typically results in criminal proceedings and legal prosecution. This depends on your local laws.

However, if you violate the license of a piece of software its original author(s) may request that you

cease the license violation

If you make no or little money off your software this is often a simple request to either stop the distribution or publish the source code.

and/or
pay damages, compensation and/or legal fees incurred by the violation.

This depends on many things, though many open-source software  organisations (that represent the software authors) will ask for a donation to their foundation or society.

1 You can look up the license of each package in Ubuntu in the directory /usr/share/doc/<PACKAGE> (where <PACKAGE> is the name of the package) in files with names like copyright or COPYING. The Free Software Foundation maintains an FAQ about GNU licenses and other open-source software licenses


How to develop application for OpenStack

What you need to do is use an SDK (Software Development Kit), from https://wiki.openstack.org/wiki/SDKs#PHP:

  php-opencloud is a software development kit (SDK) to help developers using PHP to work with OpenStack and other open clouds.
  ZendService_OpenStack is a PHP library that implements the last versions of the OpenStack API. It's 100% compliant with the
  specification of OpenStack.


How to view the `.bash_history` file via command line?

If you want to access the actual file itself, just use your favorite text editor (I use emacs but you can use pluma of gedit or vimor whatever):

emacs ~/.bash_history

That is the default location if your history file. If you don't find anything there, you may have changed the history file's name. This is stored in the $HISTFILE variable, so print it out to check its current value:

echo $HISTFILE

If, instead of the file, you just want to see your history, you can run history as @minerz029 suggested. The history command with no options just prints the contents of your $HISTFILE followed by the commands executed in the current shell that have not yet been written to that file, with line numbers.


Constant DRM entries in syslog for Ubuntu 16.04

From another source, I learned this behavior is an artifact of Xdiagnose, an application I used to diagnose past video issues. The large number of DRM lines went away after unchecking the graphics debug feature in Xdiagnose.


Any audio (not music) and video organizer?

OK, someone pointed me to digiKam, which you can configure to accept any audio type.


Ubuntu 20.04 (Gnome3 / LighDM) > lock screen on suspend

Save the following as /etc/systemd/system/lock-on-wakeup.service:
[Unit]
Description=Lock screen when waking up
Before=sleep.target suspend.target hibernate.target hybrid-sleep.target suspend-then-hibernate.target

[Service]
Type=oneshot
ExecStart=dm-tool lock ; sleep 2
Environment=XDG_SEAT_PATH=/org/freedesktop/DisplayManager/Seat0

[Install]
WantedBy=sleep.target suspend.target hibernate.target hybrid-sleep.target suspend-then-hibernate.target

Then activate this with:
sudo systemctl enable lock-on-wakeup.service

sleep 2 in ExecStart= should prevent the system to go to sleep before the lock screen activation is in effect (which would result in the user's desktop being visible for a split second after waking up, before the lock screen actually activates). If this is not sufficient, increase the value. (Run sudo systemctl daemon-reload after any modifications.) There might be more proper solutions than sleep to make sure the lock screen is in effect.
Helpful resources were especially:

https://unix.stackexchange.com/a/81694/59725
https://github.com/pop-os/pop/issues/463#issuecomment-472666569


Set a static IP to lubuntu on VirtualBox

First thing I notice is

    auto eht0

should be

    auto eth0

That would cause a device issue and not be able to bring the adapter up. Fix that first then there might be further things to troubleshoot, or that could be it.


I'm looking for Ubuntu drivers for the Broadcom BRCM 1058 Wireless adaptor

You should be able to install them by running in a terminal (Ctrl+Alt+T) :

sudo apt-get install bcmwl bcmwl-kernel-source

If those two packages are already installed, try to run :

sudo apt-get install --reinstall bcmwl-kernel-source


How can I add a shortcut to printer settings to the Desktop Panel on Ubuntu 13.10?

The shortcuts of all settings are located at /usr/share/applications. You can copy the printer settings shortcut to the desktop with:

cp /usr/share/applications/system-config-printer.desktop ~/Desktop

Or use the GUI to copy it... You then have to make it executable, by right-clicking it --> Properties --> Permissions tab --> Mark 'allow executing file as program'.

done.


How can I edit a PDF in ubuntu to change its opening settings?

If you create these pdfs with Libreoffice, you can set such preferences during pdf export (Export as pdf --> Initial view --> Magnification.

Depending on the complexity of the pdf you can also open a pdf in Libreoffice Draw and reexport it with the desired setting.

Otherwise you can use pdfXchange viewer via wine (it is commercial, but significantly cheaper than adobe pro and works flawlessly under wine), or you can give pdfedit (native) a try.

To install pdfedit: see here

To change initial view with pdfedit (from here )

Open the PDF file in pdfedit, right click the "catalog" node in the tree panel, choose "add item to dictionary"
Add property name: "PageLayout"
Select "name" and input "TwoPageRight"
Click "add and close"
Save the PDF file

This adds a name in the catalog dictionary of PDF file. It will be used by the Acrobat Reader. There are other possibilities:

SinglePage
OneColumn
TwoColumnLeft
TwoColumnRight
TwoPageLeft
TwoPageRight

"Column" means continuous page. "Page" means display as a single page. "Left" means start double pages with odd-numbered pages on the left.


How to get an Ubuntu system that boots to the command line to start the GUI?

I understand that you want to install this specific package (ubuntu-desktop) without an internet conection because yours it's slow.

Try to use the Ubuntu disc as a repository (to install the ubuntu-desktop package):
insert your ubuntu disc to reader then type:

sudo apt-cdrom add

This should add it to the sources.list file. Leave the disc inside the disc reader and then try:

sudo apt-get update

sudo apt-get install ubuntu-desktop

If you type:

sudo apt-get upgrade

It will upgrade the whole system.


How to enable full permissions on internal secondary HDD?

Your second hard drive's mount-point seems a bit weird to me. Here is the way to fix it. This involves:

Creating a new mount-point and
Editing the /etc/fstab file to automatically mount the drive at the
new mount-point.

What mount-point?
Simply put, a mount-point is a an empty folder where the drive will be mounted. For a permanently attached hard drive that is going to be mounted automtically when the system boots, I like to create the mount-point at the root of the system folder /, such as /bigdrive. Other popular choices are mount-points /mnt/bigdrive or /media/bigdrive.  See Why have both /mnt and /media?
The tradition of mounting partitions (of hard drive) as a sub-folder of /mnt/ comes from the days when one needed to manually mount the tape drives that were then attached to the system. This involved lifting a roll of magnetic tape and mounting it on a peg inside a cabinet sized computer:
The mount-point that are sub-folders of /media/ are usually automatically generated when an external drive, usually USB drive is attached in modern Ubuntu computers.
Creating a mount-point
Open a terminal by pressing Ctrl+Alt+T and enter:
sudo mkdir /bigdrive
sudo chmod -R 777 /bigdrive

If you prefer the graphical way Open Nautilus as root. How do I start Nautilus as root?

Navigate to the / and create a new folder called /bigdrive
Right click on and choose Properties.
Go to the Permissions tab.
Make sure the Group and Others can Create and Delete Files.

Click on "Change permissions of enclosed files" button and make sure
it looks like this:

Edit /etc/fstab
Let us make a copy of the original fstab file before we start editing:
sudo cp /etc/fstab /etc/fstab.old

To edit the /etc/fstab I use nano:
sudo nano /etc/fstab

Comment out the existing lines related to the internal big drive by putting a # at the beginning of the line like this:
#The 1.7tb ext4 Seagate Drive
#/dev/disk/by-uuid/6ae9faae-3242-4023-9137-8cdf65bc5d96 /mnt/6ae9faae-3242-4023-9137-8cdf65bc5d96 auto nosuid,nodev,nofail,x-gvfs-show,x-gvfs-name=Casa%20Storage 0 0

Add the following line:
UUID=6ae9faae-3242-4023-9137-8cdf65bc5d96 /bigdrive ext4 defaults 0 0

Note: the UUID is unique to each partition. So everyone should use the correct UUID for their own hardware. Do not copy it from here.
Press Ctrl+O followed by Enter to save the file and Ctrl+X to exit nano.
Test it out:
The following steps will unmount the drive from its old mount-point:
sudo umount /mnt/6ae9faae-3242-4023-9137-8cdf65bc5d96

You can type the first 2 or three numbers and letters of the long file name and press Tab in the terminal to auto-complete the rest of the name.
Then mount it at the new mount-point with the new options set in the /etc/fstab:
sudo mount -a

If all goes well you should find the existing files and folders inside /bigdrive.
Setup Samba
Based on your question I assume you have other computers running Windows and you want to setup Samba for sharing the /bigdrive with other computers running either Windows or Ubuntu.
Step 1 Open Nautilus normally and navigate to / from + Other Locations on the left pane. Right click the /bigdrive folder icon and choose "Properties" and click on the "Local Network Share" tab:

Check the box "Share this folder."
You may also want to check the other two boxes "Allow others to create and delete files in this folder." This will allow you the desktop Windows user to create and delete files on this folder.
The "Guest Access" check box is self explanatory. This may be useful if your Windows userID is not exactly the same as your Ubuntu user ID.
It may tell you Sharing service is not installed:

Click "Install Service" and let it install the software by providing the password when it prompts. You may be prompted to install more software like libpam-smbpass. Install all the software. It will ask you to restart services and click Yes.
Step 2. Go to the permissions tab and make sure it looks like this:

Click on "Change permissions of enclosed files" button and make sure it looks like this:

Now you should be able to edit files created in Ubuntu in the /bigdrive folder.
However, if you create a file in a Windows computer and put it in this folder using Samba you may not be able to open that file when you get back to this computer. This is because Windows and Ubuntu do not understand each other's file ownership and permissions. So in the Ubuntu laptop, the file created by Windows is owned by "Nobody". You will have to open Nautilus as Administrator and change the ownership and read-write permissions while in the laptop.
Step 3. Go to the Windows on the other computer and open Windows Explorer, Click on the triangle next to Network on the left panel. From the drop-down list you should be able to select the name of the computer running Ubuntu with /bigdrive.
Now you should be able to see your shared folder (say "BigDrive") from this Ubuntu computer in the Windows Explorer. Click on "bigdrive" folder and see the files in the folder. You should be able to copy files from the Public folder in Ubuntu to your Windows local folder.
Here is a step by step guide with some more details.
The Samba section of the answer is based on this answer. Read the whole answer for network file sharing using sftp if your network consists of only Ubuntu computers and now Windows.
Hope this helps


What feature is at play when Ctrl+Shift+Alt+U,E "types" an unprintable hex 000E?

Ctrl-Shift-U is the short-cut to start entering a full unicode character by hand. For example, here I've typed: Ctrl-Shift-U 0 0 b 0 enter to get the degree symbol: ° which is unicode 00b0. Here is 2665, the heart: ♥

For a list of unicode symbols start here: http://en.wikipedia.org/wiki/Unicode


First list all the packages which is  having conflict by using the following command,

apt-mark showhold

After doing so unhold by using the below command,

sudo apt-mark unhold <package name>

Once you are done with the above remove all the packages which is causing the issue and re-install it again. Hope this will help you to fix the issue. Please give it a try.


You have to:

open PSensor GUI
go to Psensor → Sensor Preferences
select needed sensor in the left list
switch to Graph tab
check Display sensor in the list of sensors checkbox
click OK


Set default folders to external HDD permanently

I've solved this by making an executable script which I added to my startup applications.
The first thing we should know is that the file with your default folders is ~/.config/user-dirs.dirs, which is where you can indicate the directories of the folders you want to have listed under "Computer" in Nautilus.
Step 1
Create the correct user-dirs.dirs file with all your desired default folders and their locations. I only had to edit two entries so I opened the original (in Terminal: gedit ~/.config/user-dirs.dirs), edited it to the correct folders and "saved as" in another location (namely ~/Documents/Miscellaneous/).
Step 2
Open up your preferred text editor, like gedit. First we want to remove the original and incorrect user-dirs.dirs file: rm ~/.config/user-dirs.dirs. Then, we want to take the correct file we created and copy it into the ~/.config folder: cp ~/FolderWithCorrectFile/user-dirs.dirs ~/.config/. Make sure to add && between the two. In my case it came out like this: rm ~/.config/user-dirs.dirs && cp ~/Documents/Miscellaneous/user-dirs.dirs ~/.config/
I saved this file in the same folder as the correct user-dirs.dirs file, but you can put it anywhere.
Step 3
Now we have to allow the file we just created to be executed as a program. The easiest way to do this is to right click on the file, go to its properties → permissions. There, check the execute tick box. Then run the file to check if it works by verifying the original user-dirs.dirs file has been replaced by your new, correct version.
Step 4
If everything worked, go to "Startup Applications". Browse and add the file we created. Next time you boot your computer all your default folders will be there.


After installing AMD RX 480 driver on Ubuntu 16.10, cannot get to login

You should be able to boot into the multiuser target with sudo systemctl set-default multi-user.target and rebooting.
Then go back to your AMD graphics installer binary and run it again, this time passing --uninstall to it.

I have this exact problem and am just using glitchy open source drivers for my graphics card since it is newer. Older graphics card have great support, I just happen to have a niche laptop. Remember to set your boot target back with sudo systemctl set-default graphical.target


There are two possible issues here.

You wrote that you set up your Raspberry Pi with "share internet connection". Usually "share internet connection" setup means NAT routing. With NAT routing, by design you can connect from network 10.42.0.* to the network on the other side of the Raspberry (10.0.0.*), but you cannot connect the other way. You need to turn off "share internet connection" - whatever it is - and configure a regular IP packet forwarding (that means, routing) on your Raspberry. Here's a tutorial on how to do this: https://tecadmin.net/enable-ip-forwarding-linux/

The devices in 10.0.0.* network need to know how to reach the devices in 10.42.0.* network. Normally, they have only one default gateway - that is the router 10.0.0.138 - and they will try to connect to everything that doesn't belong to their 10.0.0.* network via that router.

So either that router, or each of the devices in 10.0.0.* network, needs to have a route added to the routing table that tells them to reach the network 10.42.0.0/24 (or 10.42.0.0/255.255.255.0, whatever notation your system is using) via gateway 10.0.0.7 and not via the default gateway 10.0.0.138.
Also the devices in 10.42.0.* network must have the default gateway set to 10.42.0.1 to be able to talk back to devices from 10.0.0.* network. If you need these devices (and Raspberry itself) to be able to access Internet as well, Raspberry must have the default gateway set to 10.0.0.138.


I have files in a usb drive that would not delete and the terminal is not working nor accepting my password in ubuntu 14.04

If you instead boot to a live boot cd, you will (probably) be granted overriding superuser status which will permit you to delete those files.

(My assumption is that those files were written on one of your previous installations when your user name and password were different)


How to use terminal from Krusader with LXDE?

Instead of a space, put = between the argument and %d

lxterminal --working-directory=%d


Just before login-screen, a messages flashes by - how can I slow it down to read it?

You can always press the super key (Windows logo) and type "log", then click on "System Logs" and you should see a variety of logs you can browse through. They're all neatly organized so not difficult to understand them.

If you need more information, you can always manually check /var/log directory


Running Sublime 2 from the launcher opens Sublime 1 version

I fixed my problem installing sublime through the command terminal here.


Sharing sensitive Chrome Browser info between Windows and Ubuntu

Most such identifications note your computer name as well as your operating system(and the browser of course). So, it seems to be nearly impossible.


Change screen resolution of xubuntu-14.04.3 using VirtualBox running on Windows 10

You have to install the virtualbox guest additions. They change the resolution, enable drag and drop, and some more.

You can read it here:

How do I install Guest Additions in a VirtualBox VM?

Now, the resolution will change according to your virtualbox window.


Ubuntu 21.04 - high CPU spikes when a mouse is moved

Had the same issue,
I'll share this bug report, it helped a lot :
bug 1900760


What is the best tool to manage several Ubuntu stations over network?

landscape from Cannonical is the only one that I know for managing this kind of things. I have used it for managing servers before and it really is excellent


Nvidia 8400 glitches on Ubuntu 14.04 with HDMI

login to a root shell

then:

apt-get remove --purge nvidia

apt-get update

apt-get install nvidia-current

reboot

when logged in run in terminal:

sudo nvidia-xconfig

gksudo nvidia-settings


How to change color balance of the monitor

Well this is not exactly what you are asking for but it can still help.

My sugestion if for you to get the f.lux software.

Quoting their website f.lux,

  makes the color of your computer's display adapt to the time of day, warm at night and like sunlight during the day.

your eyes will live again ;)


Error partitioning hard drive during installation of Ubuntu12.04.3 LTS

The error "The creation of swap space in partition #5 of scsl1(0,0,0)(sda) failed" is probably because of something to do with your partition settings. If you are dual booting make a note of which drive your windows and other important are installed and either format or delete partitions that you may have created erroneously. Use Gdisk partitioner to view which partitions need editing.

Also remember to allocate enough swap space when installing.


How can I make ubuntu ask for my password before mounting usb-drives?

If you understand what is happening in this answer then it is easy to change it to the way you want it to behave.

Just make a file named /etc/polkit-1/localauthority/90-mandatory.d/external_mnt.pkla with the following context:

[external mount pass]
       Identity=unix-group:admin;unix-group:sudo
       Action=org.freedesktop.udisks.filesystem-mount
       ResultActive=auth_admin_keep

This should ask a password when an external device is mounted, but shouldn't ask when an internal is mounted.

Where to find more info about these things: In the manuals:  man pklocalauthority and man polkit.

Regarding the comment: How does the system know to only ask on external drives? For that to know you should look into the source code of udisks, device.c, on line 6674 starts an if branch, which is:

if (is_device_in_fstab (device, NULL))
{
  action_id = NULL;
}
else
{
  if (device->priv->device_is_system_internal)
    action_id = "org.freedesktop.udisks.filesystem-mount-system-internal";
  else
    action_id = "org.freedesktop.udisks.filesystem-mount";
}

So you can see that org.freedesktop.udisks.filesystem-mount is only for mounts which are not considered internal. And what is considered internal? That is also coded in that file, just look it up if you are curios.

Note: I just tested this, and it have worked for me.


Unable to install CUDA toolkit on ubuntu 18.04 LTS . Stuck at waiting for headers at 99%

I hope that you have resolved your issue, i faced a similar issue when running sudo apt-get install cuda with similar error message of 99% Waiting for header

E: Failed to fetch http://developer.download.nvidia.com/compute/cuda/repos/ubuntu1804/x86_64/./cuda-cupti-10-1_10.1.168-1_amd64.deb  Connection failed [IP: 192.229.232.112 80]
E: Aborting install.

All i did was repeatedly running sudo apt-get install cuda --fix-missing until the installation continued to fix the issue.

Hope this helps whoever who would potentially meet the same issue :)


How to install the most stable & latest nvidia driver in 12.04?

Regarding: most latest and stable release

Open dash with the super key.

Start typing addi

It will show an icon with additional drivers underneath. Check what drivers it shows and pick one that works best.

Example:

Installing drivers with a PPA tends to be bleeding edge and unstable versions or give support to abandoned drivers or old cards etc. Keep away from those if you are not 100% sure how to fix problems that arise from those drivers.


Don't tell me that, you have nvidia, old nvidia card having such issues with linux distros, i faced it too.

you have to install nvidia card driver by tty, reference http://www.howopensource.com/2012/10/install-nvidia-geforce-driver-in-ubuntu-12-10-12-04-using-ppa/

Tip : If you have kde based linux os ex: linux mint (KDE), Go to system setting >> Desktop effects >> Advance , and click OPENGL 1.2

I know you cannot see anything but if you shake your mouse on the screen you will get idea where is the options listed.

i am just sharing my experience, i know its irritating.


gnome-session-quit to logout does not work when run as root with sudo

I'm not entirely sure what you're trying to do but the reason the sudo command is failing is because you have started the X server as pandya and are not exporting pandya's environment variables that allow you to communicate with the running Gnome session.

So, this will allow you to kill your Gnome session:

sudo -E -u pandya gnome-session-quit

From man sudo:

  -E, --preserve-env

  Indicates to the security policy that the user wishes to pre‐
                   serve their existing environment variables.  The security
                   policy may return an error if the user does not have permis‐
                   sion to preserve the environment.

If you want to have a script that runs some commands as root and then want it to be able to log you out, you can do it as follows:

Create the script, without sudo for the privileged commands but with sudo for the logout. For example:

#!/bin/bash

apt-get install firefox
sudo -E -u pandya gnome-session-quit

Run the script with sudo -E:

sudo -E /path/to/script

The sudo -E script.sh ensures that your env variables are available to the script and the sudo -E -u pandya ensures that they are passed on to the gnome-session-quit call.


How to install Ubuntu from Windows XP, Vista, 7, 8 just remotely by single click?

Not sure if what you are asking is possible to do the way you want without anybody to put hands on the remote pc.

The only way I can think for now is to install a VM (virtualbox for example) and install ubuntu on it, this way you will be able to control the Ubuntu machine after install (and reboot to configure it). You may even prepare a virtual HD file locally and transfer it to the remote machine so you don't need to install ubuntu remotely.


You can remove a foreign architecture by running

sudo dpkg --remove-architecture arm64

After that, you need to update your software lists.

sudo apt update

If you still get some errors or warnings, you can try deleting all your software lists and completely re-downloading them from the server, to make sure nothing old is left. Note that the complete download will take a bit longer than usual:

sudo rm -rf /var/lib/apt/lists
sudo apt update


Archive manager which has integration into Nemo except File Roller (Archive Manager)?

Actually, Nemo can be integrated with the default archive manager shipped with Unity. Webup8 provides Nemo with a series of extensions that integrates it tightly with Unity. The steps are:

sudo add-apt-repository ppa:webupd8team/nemo
sudo apt-get update
sudo apt-get install nemo nemo-fileroller
sudo apt-get install nemo-compare nemo-dropbox nemo-media-columns nemo-pastebin nemo-seahorse nemo-share nemo-emblems nemo-image-converter nemo-rabbitvcs

After this, among many other improvements, you should have the "Extract Here" and "Compress..." options in the context menu.


How to tell if I have a firewall installed on my VM

Most of the time, whatever the firewall tool you use, the low level firewalling stuff is made with iptables.

So with iptables -L, you should be able to tell if there is a firewall running. Not making one. Just checking.

Unless you use nftables, but this could hardly be the case.


Dragon Age: Origins with PlayOnLinux have low fps

Do you have "Nvidia Optimus" - Technology ?

Then try this ...

https://wiki.ubuntu.com/Bumblebee

& then install this...

http://wiki.ubuntuusers.de/Hybrid-Grafikkarten/primus

I am playing with primus... It's awesome :)


Can't login Ubuntu 20.04 due to wrong language

Changing the system language does not necessarily change the keyboard settings.
When logging in, try using the onscreen keyboard - > click on the little flag bellow and try changing the keyboards setings from there.
Or after logged in from the tty (alt F1-F3 black screen terminal), go to settings, Languages - Input sources and add/change to english input.


How can I configure the buttons on a Corsair gaming mouse?

Unfortunately, Corsair doesn't seem to want to support linux at all. However, there are a couple of work arounds. Although it's important to note that I haven't tested these solutions myself. In addition, my M95 doesn't use the config that's on it when I'm on Linux, but it works on Windows.

1: Windows VM

You could use VirtualBox and a Windows virtual machine to configure the mouse. Not ideal, but it works.

Note: A second mouse is recommended.

Setup

Download a Windows VirtualBox VM for IE and Edge development from Microsoft. These expire after 90 days, so remember to make a snapshot of the VM after you install the driver software.
While that's downloading, install VirtualBox:

sudo apt-get install virtualbox
Add your user to the "vboxusers" group (very important):

sudo useradd -G vboxusers username
Log out, and back in for this to take effect (also very important).
Open the virtual machine.
Install the Guest Additions in the VM.
Install the M95 driver software.
Make a snapshot of the VM.
You are now done with setting up the VM.

Modifying Mouse Configs

Note: You will probably want to have a second mouse on hand.

Open the VM, if you haven't already.
In the VirtualBox tool bar, go to Devices > USB Devices > Corsair M95 Gaming Mouse. This will disable your mouse outside of the virtual machine. If you get stuck: Host + H to do a safe shutdown, Host + Q to force the VM to quit. (Host = RightCtrl by default.)
In the M95 driver software, make your changes and save them.
Export the config files and transfer them to the host for less headache later.
Exit the VM in however way you like.
All done!

2: Use Windows

Alternatively, you could just boot into Windows and make your changes there.


undefined reference to 'dlopen' 'dlclose' 'dlerror' 'dlsym

Try to run configure again as ./configure LDFLAGS=-Wl,--no-as-needed, then run make again. It helped me compiling COIN-OR OS on Ubuntu 13.10, where I had the exact same error.

[source of this solution]


I get this error while updating and installing software : perl: warning: Setting locale failed

Run:

sudo dpkg-reconfigure locales

If that doesn't work, try adding the following line to /etc/environment and reboot.

LC_ALL="en_GB.utf8"

Or if you are in the US,

LC_ALL="en_US.UTF-8"

For additional information see:

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


"Connection reset by peer" when getting sshfs to mount?

Have you added the user pi to the www-data group?

sudo usermod -a -G www-data  pi


What are the advantages/disadvantages of the new encryption feature in ubuntu 13.10

1) Encrypt the new Ubuntu installation for security (you will choose a security key in the next step).

What Does This Option Mean

By enabling this option you enable complete encryption of your Ubuntu partition on your hard drive. Every time you boot your computer into Ubuntu you'll need to provide a passphrase so that you can access your Ubuntu partition. Note that this is separate from the password you use to log into a user, which you would still need to provide after giving your passphrase.

When you don't encrypt, your data is shown in plain text which anyone can read; data is not stored with security in mind. In a situation where your computer is stolen, the thieves could easily read any data contained in your operating system. Your user password does not necessarily protect your data because the thieves could just use a Ubuntu LiveCD (for example) to bypass this to gain access.

In other words, your password is like the front door key to your house which contains nicely organized valuables (data). Unfortunately, there are alternatives to bypassing this security, like smashing a window, so in the end a thief won't have much trouble finding and stealing anything of value in your organized home.

Advantage

The advantage of encrypting your Ubuntu partition is you can be confident that an "attacker" that has physical access to your drive will be highly unlikely to recover any data at all. Remember, this will include data which you may not consider important, such as your program files, since the entire Ubuntu partition gets encrypted.

To continue with the analogy, your house is now a complete dump; encrypted data appears scrambled and random. Even if the thief gains access to the house they will have a hard time finding/ getting anything of value.

Disadvantages

The disadvantages (at least as many I can think of or have come across) are:

There is some computational overhead, meaning your system will run slower. Although, this is usually insignificant with modern CPUs with AES-NI hardware.
You have to remember a passphrase, as well as a login password to start using Ubuntu.
If you use anti-theft software like Prey, the thief will have a hard time logging in. Hence, these anti-theft tools can become useless. However, this can be circumvented by giving the thief an alternative dummy OS partition to use that you wouldn't normally use yourself.
Data recovery becomes more difficult since you can't just 'look' at your partition, you have to also decrypt it as well.
Losing or forgetting your passphrase will mean you will lose access to important data; you will be considered no different to a thief. This really should never happen unless you suffer a severe head injury. Although, you can avoid this unexpected disaster by backing up important data elsewhere, which you should be doing regardless.

Also...

It should be said that there is a 'lighter' weight way of encrypting by just encrypting your Ubuntu '/home'; /home is usually where anything of value is stored for a typical user). When using this method, you only need the user password when booting and logging in. The passphrase which you choose is only ever used specifically by you when you need to recover data and you are unable to login anymore, for instance, because your Ubuntu somehow became corrupted.

  2) Use LVM with the new Ubuntu installation (this will set up Logical Volume Management. It allows taking snapshots and easier partition resizing)

This page summaries LVM well. Essentially, if you plan on playing around with partitions often or require advanced and flexible partitioning then you may want to consider ticking this to make life easier. There aren't really any disadvantages for a typical user.


when a older kernel is running well.

check if update was without error, meaning packages are in good status; and package linux-generic is on your system.
dpkg -l | egrep -v '^ii|rc'

If not check with
df -h;df -i

free place and inodes are there (especially you have an own /boot filesystem)
Free place in /boot
and how to proceed
fixing unterupted apt

Looking for closed source modules
dkms status

is every module  successfully build and installed in the new kernel.
If not boot the concerned kernel
dkms autoinstall


Try this:
$ sudo raidutil modify volume --expand -n R1V1 -s 100%


Three introductory statements:

Welcome to Ask Ubuntu.
Ubuntu is an operating system!
Ask Ubuntu is a site that supports Ubuntu users and developers.

With those in mind, any answer you get here is almost certainly going to be from somebody who uses Ubuntu, and they're probably going to suggest you try Ubuntu.

Ubuntu is a great OS but in the interest of balance I'd be irresponsible to blindly tell you to wipe your system and stick Ubuntu on and hope everything goes fine.

The main issue of any OS migration is the applications you use. Browsing is just fine but what "business purposes" are you talking about? Do you need to run certain software? Windows software is largely incompatible with other operating systems (although there are workarounds).

I would definitely suggest you download Ubuntu and try it for a few hours. It's free to download. Burn it to a CD/USB or install it under Windows and restart the machine (there is help on the download page). If it works well for you, you can look at doing a proper install and migrating your data over.


Once you have made a bootable USB of Ubuntu installation medium, here's what you do.

You have to tell your BIOS to use the USB drive as the boot medium. This is probably not the default in a new system so you'll have to do it. Here's a link to an HP document on setting the boot order: https://support.hp.com/ca-en/document/c00364979.

When the computer is starting up it looks to this list of boot mediums to find which medium to try first. For example you could set the order to USB,DVD,Harddisk. The system will look down this list to find the first one with a bootable medium.

The USB option may not appear as an option in your BIOS screen unless you have a bootable drive in one of your USB slots. So before you start your computer, put your bootable USB drive into a slot. You have only a few seconds to press the BIOS entry key so be ready to press it right away.

Once you're in the BIOS dialog system your BIOS screens will tell you how to change the boot order. The link above will help.

NOTE that it is not enough to just copy the iso to the USB drive. You will have to use a utility that creates a bootable image. The Ubuntu site has clear instructions on how to do this. The comments to your question give many reliable sources.


Mounting hard drive to an existing folder

The existing files in /home are neither moved nor lost. They remain inaccessible from /home until you unmount the driver. Any changes you make in /home after mounting are reflected on the contents of the external drive, and the contents of /home remain unaffected. It would be better if you chose a subdirectory to mount.


Script in /etc/init.d/ does not run in Ubuntu 15.10

Yup, you did something wrong when looking for the file.

When you ran cd /home/foo/Documents/ and then ls -l -a .boot_log you were attempting to find that file in the /home/foo/Documents/ folder.

However, your script is storing it in your home directory (/home/foo/), as per >> /home/foo/.boot_log. Try running ls -la .boot_log in /home/foo/ and the file should show up.


You should be able to run it as though it was a normal Ubuntu distro, as long as you compile it first.

Steps for compiling on Ubuntu here.

You may be able to compile it in Windows or another OS as well with g++ myprog.cpp -o myprog (where myprog.cpp is the written C program, and myprog is the compiled output), if the Ubuntu Touch distro does not allow it.


How can I modify the Live CD to start into a live session ("try ubuntu") directly?

I ended up removing ubiquity and that made the live disk boot straight to the desktop.

apt-get purge ubiquity


How do I display Chinese/Japanese characters in a Linux VT console?

I don't think it's possible.  There is only room for a few hundred chars in the standard vga/console.  Perhaps one of the Japanese alphabets would technically be possible, but not Chinese.  A few more details are here: https://askubuntu.com/a/98750/116108

What I would suggest is to try fbterm:

sudo apt-get install fbterm

It can display a much wider range of UTF-8, so there is a decent chance it will support Chinese if the default font does.  Perhaps that can be changed too.

Another choice of last resort might be Pinyin, though I have no idea if significant number of Chinese understand it.


So I managed to fix it by using the command

  setxkbmap dk

However, the problem still appears from time to time, but the above command always works. I still think its weird that it randomly resets the language sometimes, so if anyone has a permanent solution to this, please tell.


Unity launcher: Tor Browser opens as Firefox icon

I cannot vouch for the safety (in terms of Tor's purposes and goals) of the next solution, but this is what I did in my own case.

I suppose that you already have tor browser registered as an app in your system, but if you don't than run this command from the directory containing the unpacked stuff, it must be something like:

~/tor-browser_en-US

And run this command:

~/tor-browser_en-US$ ./start-tor-browser.desktop --register-app

Then the solution itself. You should have a launcher file ~/.local/share/applications/start-tor-browser.desktop file. Drag it to your launcher bar.
And in the file itself change the line:

Exec=sh -c '"/home/<username>/tor-browser_en-US/Browser/start-tor-browser" --detach || ([ !  -x "/home/<username>/tor-browser_en-US/Browser/start-tor-browser" ] && "$(dirname "$*")"/Browser/start-tor-browser --detach)' dummy %k

to this one (with substitution of the username properly):

Exec=/home/<username>/tor-browser_en-US/Browser/start-tor-browser

That is make it to call the executable directly, not via a shell.

That's it, but I would like to repeat that I'm not sure how these changes affect the abilities of Tor browser. I suppose that nothing harmful was done.


Go to

System Settings -> Security & Privacy -> Diagnostics -> Uncheck Send Occasional system information to Canonical

I believe what you are referring to is(Zeitgeist) a feature of Ubuntu for you.  It isn't for advertising purposes.  It is to display information to you about recent files, log events, and other things you may find useful and display some of that information to you when searching in the dash. Some of this information can be shared and you can decide what is ok to share by using the answer from @DnrDevil.  Be aware that this information also has benefits for you as well in the Dash.

Ubuntu does have services for monitoring systems like Landscape that is intended for Enterprise usage, or for a savy individual with many Ubuntu systems and not really for Canonical/Ubuntu Community.

I think what you may be confused about is Canonical having included in the dash "Online Search Results" which are sometimes linked to Amazon links with their affiliate code.  Not exactly tracking your usage of the desktop though.  This will be removed from what I have heard in 16.04 the next LTS.

Although if you don't have a need for this you can turn it all off easily.  You can also easily remove it as well.

You can remove landscape if you never plan to use it.  I haven't removed any of these things as I usually just disable them though so make sure you research doing that.

To understand privacy here is a great resource - http://www.ubuntu.com/legal/terms-and-policies/privacy-policy

To disable and move Zeitgeist - Disabling Zeitgeist

Also if any Scopes in the Dash bother you, you can always disable ALL of them.  Just right click on the dash plugin while browsing the dash applications tab.  Then click Disable.


can't execute my old file, same user, only rw

The problem here is that the filesystem is NTFS, which doesn't support Unix permissions. You need to use the fmask option of mount, which sets the permissions of all files on the mounted drive while it is mounted.

Note that you need to have root permissions for these commands to work.

First, unmount the drive if needed:

umount /dev/sda7

If it gives an error like:

umount: /dev/sda7: not mounted

just ignore it.

Next, create a directory to be your mountpoint:

mkdir -p /media/reigin/data

Finally, mount the drive:

 mount -o fmask=0022 /dev/sda7 /media/reigin/data

This will assign 755 permissions to every file on the drive (but directories will still have default permissions). Note that this is not permanent; you'll have to do this every time you mount the drive.


What I would suggest is a 2 step process:

Create a myapp.desktop file in  /etc/skel/.config/ directory. Everything under /etc/skel gets copied to new users' folders when they get created.  For the format of that file, look into How to add a shell script to launcher as shortcut. Don't worry about the title - the .desktop files are essentially same as Windows shortcuts, and their presence in user's ~/.config/autostart/ directory is what enables particular app to run upon GUI login.
Make the wrapper script that will run the app you want but then also remove the specific launcher, say for example

#!/bin/bash
gedit
rm ~/.config/autostart/myapp.desktop

That way the autostart entry will run only on first login, and on that first login - remove itself. Potentially, you also may want to remove the script itself if necessary. Deleting is also not necessary, you could just rename it via mv ~/.config/autostart/myapp.desktop ~/.config/autostart/myapp.desktop.bak

Please note, that you didn't specify what particular app or what specific conditions you need for that app to work, so this is only a rough example, and feel free to adapt it to your needs.

On side note, a script may not even be necessary if what you wanna do is simple. For example, you may want to have the line as follows in your .desktop file:

Exec=bash -c 'firefox && rm ~/.config/autostart/myapp.desktop' myapp`


How to retrieve my Desktop folder and its contents

The files were unlinked by the rm command. The data is still sitting there on your disk, but the link to them has been removed.

Therefore stop using the machine immediately as the more you use it, the more the unlinked files get destroyed...

Please use photorec: you can find more information about it here and here, and this video shows you how to use it.

For more info : Where do files go when the rm command is issued ?


Problem With ia32-libs-raring.list when attempting to install software

Run the command:

sudo rm -f /etc/apt/sources.list.d/ia32-libs-raring.list

That will clear the first two errors. As for installing ia32-libs, that package has been deprecated for a while now. Whatever instructions you are following are outdated. For more information see What happened to the ia32-libs package?

Also, please upgrade to Ubuntu 15.10, 15.04 will become end of life next month. You will lose updates and support and upgrading will become harder.


Did the trick for me:

sudo rescan-scsi-bus

rescan-scsi-bus is in the package scsitools, not installed by default, so maybe you will have to install it first:

sudo apt install scsitools


Try this instead:  ls -d */
it will list the directories in the current directory


Problem with installing ubuntu 14.04.1 LTS Trusty Tahr

Try this:

Ubuntu 14.04 doesn' t boot after upgrade from 12.04 installed inside Windows 8.1

It worked for me on a dual boot machine with W7. I had to edit 9 or 10 lines and my linux is back


In LibreOffice Write 5.1.6.2 go to Format > Page > Area > Fill > and select Bitmap from the dropdown selection. Click on Import Graphic and select an already saved graphic with the text you want to have as a watermark. As an example, I found "SAMPLE" as an image using Google and then saved it to my local drive but you could equally well find a graphic for "DRAFT" OR "CONFIDENTIAL" or a logo as required.

Results in:


Clear cache -- "Operation not permitted" even with sudo

You can't create a file even as root in /proc/sys/vm due to its permissions:

dr-xr-xr-x 1 root root 0 Jun  9 21:46 /proc/sys/vm

You can see that even root doesn't have write permissions which means that even root can't delete, rename or create files in this directory.

Existing files in /proc/sys/vm might be editable though if the file permissions itself are sufficient.

Files under /proc are provided by the kernel. Using WSL you don't use a Linux kernel but an emulation (lxss.sys, lxcore.sys). If a file under /proc does not exist it means it is not provided by the kernel or, in your case, the emulation.


iPhone music sync (iOS 6.1.2), is it possible yet?

It seems there is no way of syncing music without owning a copy of windows or OSx. All the workarounds (that actually work!) use virtualbox, which presupposes you have a copy of windows. It seems iTunes run through PlayonLinux or WINE will not sync your device.

Best native functionality exists in Banshee. Very limited (deleting songs).


Nautilus crashes seconds after launching

As you can read from the error message:

/home/ozuf/.local/share/gvfs-metadata/home: open: Permission denied

And confirmed by:

ls -l /home/ozuf/.local/share/gvfs-metadata/home

-rw------- 1 root root 29508 Oct 22 22:21 /home/ozuf/.local/share/gvfs-metadata/home

The file needed by Nautilus is owned by root, so you would need to run Nautilus with sudo, which you shouldn't.

To change the ownership back to your user

You can simply get the ownership of the whole directory, as it's likely some more files will be owned by root and could cause trouble in the future.

cd ~/.local/share

sudo chown $USER -R ./gvfs-metadata

That fixes the permission problem. To fix the second problem which is

ERROR:nautilus-canvas-container.c:6021:finish_adding_new_icons: assertion failed: (!container->details->auto_layout`:

From home, run cd .config and rm -rf nautilus
Also from home run .local/share and rm -rf nautilus.


How install 14.04 to virtualbox with live CD as guest on mint 17

Boot into Mint
Install Virtualbox
Start Virtualbox and choose new
Select Linux, and the version of your choose the version of your choice
Select the amount of memory you'd like to allocate (you can use the defaults)
Create a hard drive of the size and type you want
When you boot the machine for the first time, it will ask you where
to boot it from and you can choose the .iso file you downloaded
After it boots, you can install from there
You will want to install Guest Additions after it's set up


you can use the following sample .desktop file, save the following contents as somefile.desktop at your desired location, say on desktop.

[Desktop Entry]
Name=system1_ssh_terminal
Comment=launch ssh session
Exec=gnome-terminal -e 'ssh -X user@ip_of_system1'
Icon=utilities-terminal
Terminal=true
Type=Application
Categories=Application;

Don't forget to make the .desktop file executable.


How do I install ubuntu with a disk on a dell with no operating system?

Make sure you go in the BIOS and the DVD-ROM is above boot from hard drive in the list of booting priorities. Also, make sure when you burn the dvd, to select the option to "make the DVD bootable".


How are you trying to install VirtualBox? apt-get or dpkg ?You can download VirtualBox i386 or amd64 from the links.
And then run the below command,
sudo dpkg --install virtualbox-4.3*.deb
See if that helps.


Reinstalling Ubuntu 16.04 LTS on existing drive partition

You don't necessarily have to reinstall Ubuntu to enlarge its partition size. If you can shrink partitions right next to the Ubuntu partition, you can then enlarge it without having to reinstall. I suggest you include a screenshot from GParted.

If you do have partitions right next to the Ubuntu partition, all you need to do is boot from a GParted live USB (instruction here). After that, I believe you just have to shrink a partition right next to it by right-clicking and choosing the resize option, and then resize your Ubuntu partition to use up that unallocated space. Remember you can't do it from the GParted of your Ubuntu installation. You will need to boot from a GParted live USB.


I am not sure if it will help, but please check below link which has a similar kind of question that you asked:
Software Center Not Showing Installed Apps
For some people, it fixed the issue but for some, it didn't.


How to view Windows PC connected to LAN?

Sounds like you are shutting the machines down regularly, and, without a domain controller, you are unable to establish what is known as a master browser.  What I would suggest is setting up one machine as your master browser, which is easiest in Samba (see here) and leaving it on all the time.  I have a Linux based NAS device I have designated as my master browser and I never have an issue with share lists.


Please first check if video4linux and gstreamer are both installed in your system! Also, provide any output of the lsusb program that include information about your usb connected webcams (for options see man lsusb).


Why does apt think this package isn't installed?

The apt list command doesn't check just installed packages. It checks the database of all known packages from all known sources, whether installed or not.

Here's an example of apt list of an installed package:

$ apt list python3
Listing... Done
python3/cosmic-updates,now 3.6.7-1~18.10 amd64 [installed]

apt list will clearly tell you which packages are [installed].


Just set the interfaces to be DHCP, and one of them will pull an IP address in the same range as other machines on your network. The two NAT adapters will pull IPs from Virtualbox, but it'll be in a different IP range than your normal network.


Does my file system really take up 140TB?

Open disk usage analyzer and you can drill down into directories looking for large files. No need for terminal.

But

find / -type f -size +1000000000c

will find all files larger than 1Gb from a terminal. Add a | more to make it list in pages or a > /tmp/files.txt to make a text file containing all the files it finds.

  How do I know if this accurate?

Find the files that are large with above command and the results will tell you if it is. It could be a file system bug though.

sudo -i
touch /forcefsck

will force a check during the next reboot.

  What can possibly take up so much space?

Video and images can. Downloading 1 image from the latest Mars pictures from the NASA site can quickly take 1Tb ;) And the latest batch was 30 pixs. Game of Thrones all six seasons in high def is going to take up some space.

  How do I know what can be safely deleted?

That is up to you to decide. Even it is is a large file ... that in itself might not mean you want to delete it.


How can I route a system-wide ALSA EQ (alsaequal) through my volume control and connect PulseAudio to it?

As someone used to "plug and play" audio devices (eg never have to configure anything for sound) your problem "sounds" very complicated to me. However, there are generic problems with equalizers and the accepted answer there might help:

To start the pulseaudio equalizer run:

qpaeq

If this gives you the error

There was an error connecting to pulseaudio,
please make sure you have the pulseaudio dbus module loaded, exiting...

then load these two modules using pactl:

pactl load-module module-equalizer-sink
pactl load-module module-dbus-protocol

and, to make these changes permanent, edit ~/.config/pulse/default.pa (create it if necessary) and add these lines:

load-module module-equalizer-sink
load-module module-dbus-protocol


Ubuntu 13.10 GNOME: visual glitch when hovering over icons

I have the same issue, dell e7440:
00:02.0 VGA compatible controller [0300]: Intel Corporation Haswell-ULT Integrated Graphics Controller [8086:0a16] (rev 0b). I get the glitch hovering over icons and corrupted pixels while scrolling in the preview pane in thunderbird as well. I have a xps14 that is ivy bridge and it definitely does not have the same corrupt video issue.


The quick answer is 'add the following to the very end of your .bashrc file':

shopt -s histappend
export HISTSIZE='10000'
export HISTFILE="$HOME/.bash_history"
export HISTIGNORE=cd:ls:bg:fg:exit
export HISTCONTROL=ignoreboth:erasedups

...Or something like it, that's directly out of my .bashrc file.

The correct answer is 'read up on the bash shell'.
I highly recommend Learning The Bash Shell (http://oreilly.com/catalog/9781565923478).

Otherwise there's a lot of free material on the web to get you started, for example :
http:www.ibm.com/developerworks/library/l-bash.html
http://tldp.org/LDP/abs/html/

Also, Romanovzky and Dennis have a valid point - the file may already be there.
You might also make sure your user owns and can write to your .bash_history file :

sudo chown $USER:$USER $HOME/.bash_history
sudo chmod u+w $HOME/.bash_history


Clean install of Ubuntu 14.04 - Screen goes black after login, but mouse works

Turns out unity does not support my video card.  Seems there are a number of older NVIDIA cards that one would think would work with unity, but do not because they are blacklisted.  For more info on this is found here.

I tested my video card with unity:

/usr/lib/nux/unity_support_test -p

returned:

OpenGL vendor string:   NVIDIA Corporation
OpenGL renderer string: GeForce FX 5700LE/AGP/SSE2
OpenGL version string:  2.1.2 NVIDIA 173.14.39

Not software rendered:    yes
Not blacklisted:          no
GLX fbconfig:             yes
GLX texture from pixmap:  yes
GL npot or rect textures: yes
GL vertex program:        yes
GL fragment program:      yes
GL vertex buffer object:  yes
GL framebuffer object:    yes
GL version is 1.4+:       yes

Unity 3D supported:       no

I repeated this with both nouveau or nvidia-173, unity was not supported on either.

I found the following work arounds:

GNOME

I was able to run Ubuntu 14.04 with gnome instead of unity.

@tty (Ctrl + Alt + F1):

sudo apt-get update
sudo apt-get install gnome-session-flashback

reboot

@login prompt:

Click the image on the upper right of the name
Select: GNOME Flashback (Metacity)

Lubuntu or Xubuntu

An alternative to Unity and GNOME is Lubuntu or Xubuntu.

Just for the record, I did not try either of these since I was able to run Ubuntu with gnome.

Unity-2d on Ubuntu 14.04?

In Ubuntu 12.04, I remember running Unity-2d because I was not able to run unity.  In Ubuntu 12.04, we were able to select Unity-2d at the login screen similar to the way that gnome is selected in the text above.

I was able to install unity-2d @ a tty: sudo apt-get install unity-2d However, I was not able switch from unity to unity-2d.  I read some place that unity defaults to unity-2d when it can not run, apparently that did not work in my case.


Type byobu-quiet: Silence all of Byobu's status indicators and eliminate the hardstatus line
Append these lines to ~/.byobu/profile.tmux:

BYOBU_DATE=""
BYOBU_TIME=""

Close and start byobu.

Tested on Ubuntu 2019.04. It survives a reboot, too.


How can I use firefox to take full page screenshots from command line?

To make screenshots of web pages showing the whole scrollable area of the page in firefox, I propose two separate ways.

Both save an image of the page that shows all parts or the web page that you could reach by scrolling down (and right/left) - think all view positions stitched together;
For long pages, the image can easily be several thousand pixel high.

The "professional" way - using a web browser GUI-level testing and automation tool:

The automation tool Selenium - usually used for UI testing - can do full page screen shots;
It seems to be some overhead to set it up just for that task, though.

For example:

Command: open; Target: http://www.google.com
Command: captureEntirePageScreenshotAndWait; Target: \\Screenshots\\test.png

See so.SE: Screenshots using Selenium IDE Firefox plugin

To install the firefox part of Selenium, get the firefox add-on - but not from the official add-ons page - it's on the download page of Selenium as an xpi file. This is the current version.

(There are lots of add-ons for extending selenium itself (but in the technical for of a firefox add-on),  all called "Selenium ..." or even "Selenium IDE ..." on the Add-ons website - very confusing.)

The "hackish" way - using internal firefox commands by keyboard automation:

There is an internal command prompt in firefox, kind of a development tool, which, as @Fireflight pointed out, has a command to make screenshots. But, as far as I know, that can not controlled from the command shell line normally. But what we can do, is to simulate key presses to make use of it.

We need to choose a browser window, open the prompt, enter the firefox internal command (using a file name based on current date and time), run the command, and close the prompt again:

FF=$(xdotool selectwindow)
xdotool key --window $FF Shift+F2 sleep 1
xdotool type --window $FF --delay 50 "screenshot page-$(date +%Y%m%d-%H%M%S).png --fullpage "
xdotool key --window $FF Return sleep 0.5 key --window $FF Shift+F2

The command line utility xdotool can interact with X windows on the level of X11 events. We use it to choose the firefox window that shows the page, and to send the right key strokes to make the screenshot.

(This is a somewhat brittle approach: it's depending on keyboard timing, it will not work if the prompt is already opened, or contains text (To open or close it, press Shift-F2) - but if it works, it's really nice.)

As an example how this kind of screenshot looks, here's an example of man xdotool on manpages.ubuntu.com, scaled down to 20% (original 1336x15653), done with the xdotool solution:


Install Ubuntu onto an SSD with Windows on another SSD

Virtualization can have an impact on running the regular Ubuntu desktop (Unity) or Ubuntu Gnome but is more unnoticeable when using Xubuntu, Lubuntu, or Ubuntustudio. One key thing is you must enable 3D acceleration when running regular Ubuntu or Ubuntu Gnome. Of course, there is almost always an impact when running virt. compared to the real thing but Ubuntu/Linux runs much better than say OSX does in Virtualbox.

Here is a good link to a tutorial for SSD optimization.

Notably, they show how to change options to noatime and how to set the scheduler to noop as well as removing an unnecessary cron job, all to reduce SSD wear and tear.

Also, I also suggest using zram swap to reduce SSD use from swapiness. Basically, after installation, open a terminal and run the following command to create a new file:

sudo nano /etc/init.d/zram

then, copy and paste the following into the terminal:

### BEGIN INIT INFO
# Provides:          zram
# Required-Start:    $local_fs
# Required-Stop:     $local_fs
# Default-Start:     S
# Default-Stop:      0 1 6
# Short-Description: Use compressed RAM as in-memory swap
# Description:       Use compressed RAM as in-memory swap
### END INIT INFO

# Author: Antonio Galea <antonio.galea@gmail.com>
# Thanks to Przemysław Tomczyk for suggesting swapoff parallelization

FRACTION=75

MEMORY=`perl -ne'/^MemTotal:\s+(\d+)/ && print $1*1024;' < /proc/meminfo`
CPUS=`grep -c processor /proc/cpuinfo`
SIZE=$(( MEMORY * FRACTION / 100 / CPUS ))

case "$1" in
  "start")
    param=`modinfo zram|grep num_devices|cut -f2 -d:|tr -d ' '`
    modprobe zram $param=$CPUS
    for n in `seq $CPUS`; do
      i=$((n - 1))
      echo $SIZE > /sys/block/zram$i/disksize
      mkswap /dev/zram$i
      swapon /dev/zram$i -p 10
    done
    ;;
  "stop")
    for n in `seq $CPUS`; do
      i=$((n - 1))
      swapoff /dev/zram$i && echo "disabled disk $n of $CPUS" &
    done
    wait
    sleep .5
    modprobe -r zram
    ;;
  *)
    echo "Usage: `basename $0` (start | stop)"
    exit 1
    ;;
esac

When you are done, press CTRL + O and press Enter to save the file and then press CTRL + X to exit the file.

Finally, run the following three commands in an open terminal to apply zram swap compression:

First, make the file executable:

sudo chmod +x /etc/init.d/zram

Then, start zram swap compression:

sudo /etc/init.d/zram start

Finally, the following command will make it start automatically at boot time.

sudo update-rc.d zram defaults

sources:

http://command-line-computer-virus.tumblr.com/tagged/swappiness

https://wiki.debian.org/ZRam


Here is the solution

Go to terminal CTRL+ALT+F1
Login to the terminal
Make sure you have network connection
Run sudo apt-get install --reinstall ubuntu-desktop unity
Select Y, and the downloading starts (this may take one hour)
After it finishes installing, sudo service lightdm restart
GUI should appear on screen.


I cannot install anything anymore due to unmet dependencies

My suggestion is to run sudo apt-get -f install. It should walk down the dependency tree and install any missing or broken packages. If that doesn't work, try to manually install the packages by running the command:sudo apt-get install python-qt4 python-sip python-qgis-common python-psycopg2  python-qscintilla2 python-pyspatialite python:any  sip-api-11.0. If that fails, than there is something wrong with the system. As a last resort, I suggest running a release upgrade to 17.04 by running sudo do-release-upgrade and fix the problem.


Why does Texmaker install Texlive without informing?

By default, packages listed as recommended dependencies are installed along with packages. The dpkg policy manual describes recommends as:

This declares a strong, but not absolute, dependency.

The Recommends field should list packages that would be found together with this one in all but unusual installations.

See apt-cache show texmaker to see the recommended dependencies, including texlive-latex-extra. As to the separate question of whether it should be more clear about what is being installed, I suppose this is a policy decision for the relevant software center.

Note that this is different from "recommendations" in the software center.

If you wish to disable installation of recommended packages, see this question.


Upgrading Kubuntu 11.10 to 12.04 - it want to install Ubuntu 12.04 instead

Go ahead.
Kubuntu is just Ubuntu with some other packages installed. Do the upgrade. If when it finishes you get into the Unity interface(Ubuntu) at logon, then click the gear icon and select KDE, although this shouldn't happen. If there isn't even an option for KDE Plasma workspace, then simply install kubuntu-desktop using Synaptic or sudo apt-get install kubuntu-desktop.


KDE plasma graphics are not working properly

The problem was solved after a couple kernel updates, so I'm assuming it had something to do with the firmware in it. Since Ryzen is, at the moment, cutting-edge hardware, that seems to be a reasonable assumption.

Well, I'm glad support for it has gotten so much better in such a short period of time!


You can do this by choosing an appropriate GTK+ theme. There are a few in Ubuntu already, and a lot more at e.g. http://gnome-look.org/?xcontentmode=100

Note that some theme creators are more interested in the looks than in usability, so you might encounter problem when trying to use GIMP with these themes.

You can install themes for use in GIMP only without affecting your desktop or other applications, this is described in the GIMP user manual: http://docs.gimp.org/2.8/en/gimp-pimping.html#gimp-prefs-theme


apt-get autoremove doesn't accept regular expressions?

As a workaround, you can run dpkg -l|grep 'libboost.*1.40.0'|cut -d' ' -f3|xargs sudo apt-get remove --purge to remove them from your system.


Any File Manager for accessing files of linux from Windows?


Does apt care if I put the -f flag before or after the command?

Both apt-get install -f and apt-get -f install mean the same.

From man apt-get:

   -f, --fix-broken
       Fix; attempt to correct a system with broken dependencies in place. This
       option, when used with install/remove, can omit any packages to permit APT
       to deduce a likely solution. If packages are specified, these have to
       completely correct the problem. The option is sometimes necessary when
       running APT for the first time; APT itself does not allow broken package
       dependencies to exist on a system. It is possible that a system's dependency
       structure can be so corrupt as to require manual intervention (which usually
       means using dselect(1) or dpkg --remove to eliminate some of the offending
       packages). Use of this option together with -m may produce an error in some
       situations. Configuration Item: APT::Get::Fix-Broken.


For Ubuntu Desktop 20.10 (and older), and Ubuntu Server 18.04 (and older), this seems like a classic use case for a preseed file.
Ubuntu Desktop 21.04 (and newer) and Ubuntu Server 20.04 (and newer) use a different installer. Preseed files have been replaced with cloud-init files.
Both preseed and cloud-init are highly customizable.


Ctrl+A does not select all in URL bar in Chrome and Firefox

Try the following (not guaranteed to cover your problem but it's a possibility):
Open your Dash and type in "Tweak" to get to the Tweak Tool (Note that this is not the same as "Ubuntu Tweak") - alternatively, in a console type gnome-tweak-tool (if it is not currently installed, type sudo apt-get install gnome-tweak-tool to install it)
Go to the Keyboard & Mouse > Emacs input (formerly Theme section > Gtk+ Keybinding Theme). If this is set to "Emacs", then Ctrl+A will essentially act as if it were the Home key. If this is the case, change the option to "Default" to restore the usual settings.

Alternatively, in Firefox and Google Chrome you can use the shortcut Ctrl+L to select the entire title bar.


Running gnome-keyring on WSL (Windows Subsystem for Linux)

add at the end of ~/.bashrc

ssh-add -l &>/dev/null
if [ "$?" == 2 ]; then
  test -r ~/.gnome-keyring && \
    source ~/.gnome-keyring && \
    export DBUS_SESSION_BUS_ADDRESS GNOME_KEYRING_CONTROL SSH_AUTH_SOCK GPG_AGENT_INFO GNOME_KEYRING_PID

  ssh-add -l &>/dev/null
  if [ "$?" == 2 ]; then
    (umask 066; echo `dbus-launch --sh-syntax` > ~/.gnome-keyring; gnome-keyring-daemon >> ~/.gnome-keyring)
    source ~/.gnome-keyring && \
    export DBUS_SESSION_BUS_ADDRESS GNOME_KEYRING_CONTROL SSH_AUTH_SOCK GPG_AGENT_INFO GNOME_KEYRING_PID
  fi
fi

Credentials are automatically added to ssh-agent provided that both the public and private keys are inside ~/.ssh.
Keychain storing applications such as mysql-workbench(requires Xming) also work.

You can ignore this warning on bash startup

gnome-keyring-daemon: insufficient process capabilities, unsecure memory might get used

source:
https://www.reddit.com/r/bashonubuntuonwindows/comments/4yhch4/using_gnomekeyringdaemon_for_ssh_keys/


How to keep X-Server running via 'ssh -Y' after closing shell?

Running the script with an ampersand behind it means that it will be backgrounded in the shell. So, it is still running even though you get a prompt. (Type jobs at that prompt and you will see it.)

To not get the error when exiting the ssh session, either foreground the script first by typing fg at the prompt, then stop it with Ctrl+C, or stop it by typing kill %1 at the prompt.


Based on the quote you provided, it seems that the setting /desktop-icons/center-text should not be in xfdesktop-settings. Instead, it must be accessed via  xfconf-query.

Strangely, it seems that the property /desktop-icons/center-text must be set to false in order to work properly with Flatabulous. This property does not seem to be created by default. In order to make it and set it to false, you can do the following:

xfconf-query -c xfce4-desktop -p /desktop-icons/center-text -n -t bool -s false

You should see the change immediately, but you can log off or reboot if it is not showing up.


How do you turn of the touchpad when typing to avoid the cursor jumping around?

I use the Touchpad-Indicator; I have it set as a startup application in Ubuntu, and it's set to turn off the touchpad.

I'm using Unity, and first had to turn on the notification area (you don't have to leave it showing there after you've set it up, but it's a convenient tool to have for turning the touchpad back on):

gsettings set com.canonical.Unity.Panel systray-whitelist "['all']"

This allows the indicator to show in the panel.

Then install the indicator:

sudo add-apt-repository ppa:atareao/atareao
sudo apt-get update
sudo apt-get install touchpad-indicator

It works great for me with my Dell Studio.


Can I use Ubuntu Live as if it was installed?

Is there any difference for my purposes between live and installed Ubuntu?

Not much. You're going to have lower performance because you're running off a USB stick or DVD and so it'll take longer to load things. You'll also not have as much RAM available because you've got much of the system loaded into RAM.

If you're trying to compile software & other CPU intensive things I wouldn't suggest doing them on the LiveUSB/LiveDVD unless you've got 4GB or more of RAM.

  I understand I cannot store any files, but that's fine.

Actually, you can! If you use UNetBootin (which can be downloaded & run on all platforms (Windows, OS X, & Linux) you can tell it to create space on the USB stick to store changes between reboots.

Granted, you'll need something larger than 4GB (8GB+), but you can actually store stuff between LiveUSB boots. Note, this is only for Ubuntu distros:

You can also do something similar in Startup Disk Creator, but you'd need another USB stick to install the ISO on, since you obviously can't write the ISO to the USB stick you're running off of:


Using GParted to increase my space in Ubuntu without a Live USB

Boot Ubuntu Live without a USB

Use Windows Disk Manaement to shrink your Windows partition.

Place the Ubuntu ISO on your /home partition or change swap to ext4 for a while and place it there.

Add the following menuentry to /etc/grub.d/40_custom.

Menuentry
menuentry "isoname ISO" {
    rmmod tpm
    set root=(hdX,Y)
    set isofile="/[path]/[name].iso"
        loopback loop $isofile
        linux (loop)/casper/vmlinuz boot=casper iso-scan/filename=$isofile toram fsck.mode=skip --
        initrd (loop)/casper/initrd
}

Where hdX is the disk and Y is the partition number of the ISO location.

[path] is the path to the ISO file, [name] is the name of the ISO file.

Run sudo update-grub to add the menuentry to grub.cfg.

Shutdown and reboot.

Select "isoname ISO" from the GRUB menu.  (you may need to boot toram if your ISO is located on a partition you are changing).

If needed you can use sudo umount -lrf /isodevice to unmount the isodevice.

You will have access to GParted the same as if you were booted from a Live USB.


How do I make gapless audio work when using the mplayer audio output on gmusicbrowser?

Enabling the gapless option (-gapless-audio) in SMplayer2 doesn't work. So probably it (the same command) won't work in Gmusicbrowser as well.

I've tried all of the Linux music players, but only those consistently support gapless playback:

DeadBeef
Auqualung
Audacious
MPD
XMMS2

Adding the Gstreamer developer PPA solves the gapless issue in Guayadeque and may do so in Gmusicbrowser as well. Guayadeque got better by the way, and it's better than GMB.

You can find the Gstreamer developer PPA here.

Enter in a terminal:

sudo add-apt-repository ppa:gstreamer-developers/ppa
sudo apt-get update

Then launch Synaptic and on the left click Status, then click Installed (upgradable) and upgrade all the gstreamer related packages. I've left one of them asking to remove many other packages. Installed others and closed Synaptic.

Then Update manager itself asked to upgrade the one I've left un-upgraded before. Updated this as well accepting the remove gnome-media warning.

No problem so far. Guayadeque plays gaplessly now.


On an SSD, are there any advantages to a swap partition over a swap file?


I had the same problem. I was able to finally get it working (after several attempts of removing and re-installing the tools, etc.) by

Gain console access by Ctrl-Alt-Fn-F1 and log in
Fix another issue that I recommend you fix first, since you're going to be forcing a reconfiguration anyway, which deals with the screen rescaling correctly.

See this Parallels forum thread, though for me, when I cd to /etc/X11 there was no xorg.conf at all, but there WAS one with a date appended to the filename that looked like right before I installed Parallels Tools. It looked the same as in the post, so I mv xorg.conf.[datestring] xorg.conf
rm -rf ~/.config
rm -rf ~/.compiz
sudo reboot
This will force compiz to recreate its config, which is somehow being corrupted with the Parallels Tools install.

Yay, all better! At least for me...


Krita Fill Tool Keeps covering everything

Recently I had the same problem, searched online for solutions and found other people suggesting reduce threshold and stuff.

So I went messing with the fill tool option ;then suddenly found out an obvious and simple solution.

      UNCHECK everything in the tool option, it should work perfectly fine now :)


can't set resolution 1680x1050 in NVIDIA driver (Error of failed request: BadMatch (invalid parameter attributes))

cabel DVI instead of VGA solved the problem.


Is there any way to take my current setup and put it on a live disk, then install it to another machine?

No, you cannot :)! (just kidding).

There is remastersys. It is highly documented, so I won't bother to re-document it here ^^!
Here is a link: http://www.ubuntugeek.com/creating-custom-ubuntu-live-cd-with-remastersys.html

Keep in mind this only keeps the software you have installed plus a few other bits and pieces. To get your home folder etc copied, you will need to manual transfer that data yourself, the instructions for which would be better off in another question/answer couple.

Most of your settings will not be transfered automatically, except for what it stored in the system wide configuration. This is a limitation of the scripts used to create the live environment.

To counter this, you can copy your themes and icons to /usr/share/themes and /usr/share/icons respectively, as well as set the gconf entries for your gtk/icon/metacity themes using gconf-editor to default (sorry I could not capture the menu in my screenshot). (right click the entry, then click set as default)

A more extensive option (sorry I could not find one of the the links I was looking for) is to create/customize a live cd (as according to this guide).

After installing this system, you could "make it like your existing system" using a few commands.

The steps to this are described in detail here.

No matter what method you choose, always consider carefully, before attempting such an operation, and wherever possible, try to backup your critical data.


I added simple sleep command to the stop section of the init script as suggested by @user1133275. This works well. Of course this could be optimized, but it is good enough for the time being.

`stop() {
    [ -z "$VBOXAUTOSTART_DB" ] && exit 0
    [ -z "$VBOXAUTOSTART_CONFIG" ] && exit 0

PARAMS="--stop --config $VBOXAUTOSTART_CONFIG"
# prevent inheriting this setting to VBoxSVC
unset VBOX_RELEASE_LOG_DEST

for user in `ls $VBOXAUTOSTART_DB/*.stop`
do
    start_daemon `basename $user | sed -ne "s/\(.*\).stop/\1/p"` $binary $PARAMS
done
sleep 40
return $RETVAL

}
`


Dual boot Windows 10 & Ubuntu 18.04 - How to tell grub not to show and boot directly to Windows 10

The file /etc/default/grub  contains a line:

GRUB_TIMEOUT=10

edit the file and make the 10 to 0 to hide the grub menu. You may force the grub menu by holding down a key, shift or tab.

Making Windows the default may be done by renaming the file
/etc/grub.d/30_os-prober to /etc/grub.d/06_os-prober, so it gets run before the 10_linux file.

sudo mv /etc/grub.d/30_os-prober /etc/grub.d/06_os-prober

In the 30_os-prober file, change the quick_boot=1 to quick_boot=0 to keep the timeout value from being reset in certain cases.


Very problematic installation of Ubuntu on Asus VivoBook Pro N752VX

I've finally found my solution.

Reinstall Ubuntu, just to be sure.

Boot with the nomodeset parameter.
Then the system should boot with the nouveau drivers at NATIVE resolution. Make sure to disable Secure Boot at installation, that was the only thing I did different the last installation. (I disabled it in the bios a long time ago)
Then go to the Additional Drivers page, select the NVIDIA Graphics Drivers, install them AND DON'T REBOOT.
When the installation completes, press CTRL + ALT + F1, login and run nvidia-xconfig as root to complete the installation.

The last line should say something like X11 configuration file created at /etc/X11/X11.conf

Then reboot (and make sure you boot without the nomodeset parameter) and your NVIDIA driver installation should work.

EDIT:

It broke again, no startup log or something.


Flash appears to be missing or broken in all browsers

What version of Ubuntu are your running 32bit or 64bit? If you are running 64bit I may have a solution for you.

sudo apt-get --purge remove flashplugin-installer
sudo apt-get --purge autoremove
sudo add-apt-repository ppa:sevenmachines/flash
sudo apt-get update
sudo apt-get install flashplugin64-installer

Then close all browsers, then rerun. Gives you 64bit for your 64bit OS.

https://answers.launchpad.net/ubuntu/+source/flashplugin-nonfree/+question/158539


Program installation problems on Windows Guest

This is usually a problem when running .exe files from a virtual box shared folder on the windows guest. The solution is to run the .exe using UNC paths ie In your Explorer (in Windows) go to \Vboxsvr\your shared folder\path\to\folder\with\exe and run the .exe from there.

Here's some more info on that: http://compnetworking.about.com/od/windowsnetworking/g/unc-name.htm


What happen in the partition when I uninstall Ubuntu?

Wubi stores its data in one or more files. The file(s), which are as big as your installation, will be deleted. This will remove:

Your files in your home folder
Your Ubuntu programs, and any Windows programs you installed in Ubuntu using WINE.
If you are using SSH or PGP keys, they will be removed unless you make a backup.
The Ubuntu operating system, and its bootloader.
The loopback partition stored in the file for Wubi. It is important to note that this is a file with a "virtual" partition, not an actual partition on your disk.

These won't be destroyed:

Windows programs installed in Windows
Documents in your My Documents folder, or any documents/settings made on Windows. This includes, on Vista or higher, any files within your user's folder.
Windows itself.
The Windows bootloader.
Anything you put in /host on Ubuntu as that is just a reference to your Windows disk.
Your Windows partition or any other actual partitions on your disk.

Since you used Wubi, the disk space given to Ubuntu will be automatically reclaimed.


remove systemd components in ubuntu 14.04

The init system I believe is the component you are referring to.  There are 2 major Branches of init systems

BSD Init
SysV Init

TLDR

SystemD is a child of SysV.  It replaced Upstart(which was also a replacement for SysV) starting in Ubuntu 14.10.  Every major distro of Linux now uses systemd as the default init system.  The only one that I can think of that still uses SysV is Gentoo, and our userbase is split on the issue of adoption of systemd as the default.

The major reasons that systemd is used is for ease of configuration, and that upstream GNOME has adopted it as the default init for the GNOME 3.X Desktop.  Consequently, Unity was created as a replacement for GNOME at the release of about Ubuntu 12 due to a disagreement on how to proceed between Upstart and systemd.

The short answer is No, you cannot go back to SysV, as the init system is chosen by the Ubuntu OS Maintainers at Canonical


How do I add a kernel boot parameter on live session itself?

For me, I just needed to install grub.

sudo apt-get update;
sudo apt-get install grub

This command works fine now -

sudo update-grub


2 DKMS drivers won't build correctly when installing new kernel after software update

Edit these dkms.conf files:

for the rtl8812au...

sudo -H gedit /usr/src/rtl8812au-4.3.8.12175.20140902+dfsg/dkms.conf
sudo -H gedit /var/lib/dkms/rtl8812au/4.3.8.12175.20140902+dfsg/build/dkms.conf

for the rtl8814au...

sudo -H gedit /usr/src/rtl8814au-4.3.17.13720.20150622_beta_led/dkms.conf
sudo -H gedit /var/lib/dkms/rtl8814au/4.3.17.13720.20150622_beta_led/build/dkms.conf

and replace:

MAKE="'make' all"

with this line:

MAKE[0]="'make' all KVER=${kernelver}"


Since this is a new install, this is probably a different issue, but I sometimes experience slow shutdowns when I have a Windows Share mounted with samba.  I'm not sure what happens to the share, but if I umount it first, the shutdowns are normal..


My PPA contains a libunrar package, if you don't feel like messing around with a manual install.

sudo apt-add-repository ppa:bodiltv/ppa
sudo apt-get update
sudo apt-get install calibre

(or just libunrar : sudo apt-get install libunrar)


Php artisan migrate unable to access mysql database

Edit your .env file by adding the DATABASE_URL if it's not already there and set it to the following:

DATABASE_URL=mysql://user:password@127.0.0.1/dbname

mysql can be replaced by any other driver depending on the one you use.


As you can see in screen captures Paper gtk theme is intented to be used with Gnome Shell and it's "tittlebars".

Other desktops like Unity won't provide an ideal experience.


Error with systemd-sysv libnss-systemd:amd64 libpulsedsp:amd64 network-manager gdm3 network-manager-gnome

It was solved by
sudo apt-get update and
sudo apt-get install --fix-missing.
Thus I could install the nvidia-driver (460).


I am using Burg with Natty with no issues so far. The general instructions to install it work Ok. Remember to run sudo burg-install /dev/sda(or your device in place of /dev/sda


To get it to boot, you can restart your computer into single user mode to clean up. turn the computer on, at the grub screen hit e to edit the entry. add 'single' to the end of the first grub line and press alt+x to boot. Your system will boot and you can use df -h to see the amount of free space, and du -sh /* to see what directory branches have the most stuff in then that you need to remove some of to get your computer to boot again.
  To find out what your username is, just look in /etc/passwd while in single user mode. Use "passwd " to change the password of the user if you don't know it.


Run Python script when a file has been added to a folder

Python has a module called "watchdog" that does exactly what you want.

Create a watchdog from the example. The example only echoes to console so you can add logic there to do what you want to do.
Execute the watchdog from a systemd service you create.

I made tons of these and when you get the hang of them it takes less than 15 minutes to create one from scratch.


Logitech Media Server web interface won't open on Ubuntu 14.04

If you are using mediacenter version 7.7 it might be a problem with the perl version in 14.04. Installing version 7.8.0 might help. I did the trick for me.

see link for the solution
and this for more details


Nonexistent display (Unknown Display) messing things up

after installing the nvidia drivers the phantom display is gone. I've reached my goal to be able to comfigure nvidia

The details are in the original post. Hope this saves someone the time i spent investigating the matter.

Cheers.


nautilus behaves differently when typing text than before

found a way:

dconf-editor

/org/gnome/nautilus/preferences/enable-interactive-search

"Use default value: off"

"Custom value: True"

Or:

gsettings set org.gnome.nautilus.preferences enable-interactive-search "true"


Is it possible that your mouse has been recognized as a touchpad? By default, touchpad is disabled when typing. Go to the settings / mouse and touchpad, and inspect the options there.


Yes, this is internal to bash, and controlled by the page-completions shell option.  I don't think you can configure it other than turning it on and off.  (Well, you can set print-completions-horizontally.)