What is the difference between bzr lp-propose and bzr lp-propose-merge?

bzr lp-propose and bzr lp-propose-merge are the same command (lp-propose being an alias of  lp-propose-merge):

$ bzr lp-propose --help
Purpose: Propose merging a branch on Launchpad.
Usage:   bzr lp-propose-merge [SUBMIT_BRANCH]

Options:
  --staging             Propose the merge on staging.
  -v, --verbose         Display more information.
  -R ARG, --review=ARG  Requested reviewer and optional type.
  --fixes=ARG           The bug this proposal fixes.
  -q, --quiet           Only display errors and warnings.
  --usage               Show usage message and options.
  -m ARG, --message=ARG
                        Commit message.
  --approve             Mark the proposal as approved immediately, setting the
                        approved revision to tip.
  -h, --help            Show help message.

Description:
  This will open your usual editor to provide the initial comment.  When it
  has created the proposal, it will open it in your default web browser.

  The branch will be proposed to merge into SUBMIT_BRANCH.  If SUBMIT_BRANCH
  is not supplied, the remembered submit branch will be used.  If no submit
  branch is remembered, the development focus will be used.

  By default, the SUBMIT_BRANCH's review team will be requested to review
  the merge proposal.  This can be overriden by specifying --review (-R).
  The parameter the launchpad account name of the desired reviewer.  This
  may optionally be followed by '=' and the review type.  For example:

    bzr lp-propose-merge --review jrandom --review review-team=qa

  This will propose a merge,  request "jrandom" to perform a review of
  unspecified type, and request "review-team" to perform a "qa" review.

Aliases:  lp-submit, lp-propose
From:     plugin "launchpad"


Installing steam on Ubuntu 19.10 using terminal:

Download a package: wget https://steamcdn-a.akamaihd.net/client/installer/steam.deb
Install it: cd ~/Downloads && sudo dpkg -i steam_latest.deb && sudo apt install -f
It asks about Starting steam to configure it for current user. I click the button and input my user's password when it prompts.
In my case it also wants to install some additional packages:

 Steam needs to install these additional packages:
    libgl1-mesa-dri:i386, libgl1-mesa-glx:i386, libc6:i386

Hit Enter to start packages downloading and installing.
At the end it asks to Press return to continue:. I hit Enter and it closes terminal window. After this Steam window with Updating Steam... progress bar appears a few times.

At the end, the window appears:

To uninstall it, run in terminal:

sudo apt purge steam-launcher
sudo rm -fr ~/.local/share/Steam && rm -fr ~/.steam

I have Gnome Wayland DE, with proprietary Nvidia GT220 drivers properly installed from repositories and 4.19.100-xanmod48 kernel.


Since you are using Windows, you should download the windows version of UNetbootin from here. You do not have to put it in UNetbootin in USB but install it in your Windows.

After you've downloaded, run UNetbootin, then

select the "disk image" option and
supply it with the Ubuntu ISO file you have downloaded
Select your USB drive from the list and
click OK.


Get Back Ubuntu's GRUB menu with Ubuntu first

If you haven't found an answer yet.

Looks like you only have 1 hard drive /dev/sda, right?  If that is the case, boot to Ubuntu, from the terminal type in:

sudo grub-install /dev/sda

That should override the GRUB that was installed by Mint.  Then you will have to update the GRUB again:

sudo update-grub

Hope this helps!


How to run an application source code on ubuntu?

Before you try any of the following methods check README or INSTALL file it would be carrying whole info on installation.
I'll give you some common installation methods.
Make sure to do all the following things as root otherwise it may cause such "Permission Denied" errors.
An easy way to do everything as root : At the beginning write sudo bash. It would open a bash as root it reduces lots of efforts writing sudo every time.

First extract the source code with

tar -xvzf something.tar.gz

1)With make file.

What ever your app is if it can be installed it should have a Make file in it. If there is a file named MAKE your app source work is now easy as pie.

Just lead the terminal to the source code folder cd /path/to/source/ (use tab key instead of writing whole path) and then write make
It may ask you to configure and if it ask so it would also give instructions how to do so. Configurations are dependent on app so I can't help on it without the app name.

If it doesn't ask to config, it'll be easier now just write make install and you're done.

There might be some errors like some packges requires so just install packges using apt.
i.e. apt-get install packgename

2)Without MAKE file.

In case the first method goes wrong with error i.e "Make file not found" this may work.

Check if there is a bin folder in the source, lead the terminal to the bin folder.

Run a proper executable you think is the main executable of the app using ./appname in this case the app is portable and you can use it without installation.
Probably this method never works in case you have the zero compiled source code.

Or there may be such APPNAME.sh anything like install.sh run it with sh something.sh and if it runs without errors it's all yours.

However you can always install well known apps using apt.


Those images are downloaded from the Internet to make Ubuntu available in the Horizon dashboard to launch cloud instances with. Autopilot is trying to put them in place before your first login.

Can your newfangled OpenStack setup connect to the Internet?


The solution here is more of how to properly save a BitLocker encrypted file from NTFS running Windows 10 to an EXT4 unencrypted filesystem running Kubuntu Linux.  Opening the BitLocker encrytped disk and saving to an EXT4 unencrypted partition will NOT yield an unencrypted EXT4 file. You must first change permissions under Windows 10 to "personal".

Enabling or disabling "fast boot" in the BIOS had no effect.


What Horoscope or Astrology software is available?

I just wrote this... Seems like it would be as good as anything else.

if [ $[`expr '(' $RANDOM '*' 2 / 32767 ')'`] -eq 1 ]; then echo "Today will be awesome"; else echo "Back to bed, today will suck"; fi

A shorter version, for Bash:

(($RANDOM % 2)) && echo "Today will be a good day" || echo "Back to bed, today will stink"


Lubuntu 14.04 b43 missing firmware other solutions haven't worked

Amazingly after trying this before several times, I have fixed it using

sudo apt-get update && apt-cache search b43

To find the firmware package. Then again:

sudo apt-get install firmware-b43-installer

No idea what I did differently this time


How to restore ubuntu softwares ( including built in)?

1) Reinstall ubuntu-desktop and unity-control-center, this gives you back the built-in software...

sudo apt-get --reinstall install ubuntu-desktop
sudo apt-get --reinstall install unity-control-center

2) Reinstall your lost personal software manually with the Software Center or over the Terminal

Fortunately, sudo apt-get remove ... keeps the configuration files of all removed software on your system. Hence, reinstalling the missing software is the same as restoring it!

3) Now, if you want, clean-up your system as follows...

Remove unneeded packages:

sudo apt-get autoremove

Get rid of partial packages:

sudo apt-get autoclean

Get rid of 'orphaned' packages:

sudo deborphan | xargs sudo apt-get -y remove --purge

Remove configuration files of uninstalled packages:

dpkg -l | awk '/^rc/ {print $2}' | xargs sudo dpkg --purge

Clean out unused package stuff (cache):

sudo apt-get clean

4) Bring your system up-to-date...

sudo apt-get update
sudo apt-get upgrade


I can't open minecraft.jar on xfce4 on acer C720 chromebook

okay, first you need to install java, run the following command

sudo apt-get install openjdk-8-jre

Afterward you need to mark the file as executable, find the file and right click it, find the option marked "properties". A new window will pop up, at the top select permissions, then at the bottom checkmark "allow executing file as program". Then exit out of the window,and double click on the file (minecraft.jar).

If this answer helped you please mark it as accepted.


I just had to change the Analog Output in Alsamixer to Multichannel for the rear panel output to work.

Seen here: https://ubuntuforums.org/showthread.php?t=2261950


Can't find C: and D: disks in ubuntu 16.04

Your files are now history
The option you selected doesn't just erase the programs and operating system, it formats the entire drive, and wipes out the partition table and MFT.
You can try to recover you partitions with TestDisk as described in this answer, but no guarantees.


open your terminal with CTRL+ALT+T and type as

sudo apt-get install --reinstall python3.3

that will fix your issue.


photoshop alternative for front end developers on ubuntu

There are top notch alternative software for Photoshop like GIMP and Avocode. I'm not sure if they can serve you what you need.
By the way You can use Photoshop with help of wine
Check this out: How to Install and Use Wine to Run Windows Applications on Linux


http://us.archive.ubuntu.com is up.
But your PC cannot resolve the DNS for it.
One work around is to try and edit /etc/resolv.conf and add a line:
nameserver 1.1.1.1

at the very end.
Another work around is for you to tell your PC where us.archive.ubuntu.com is pointed to.
To do that you can add the following line in /etc/hosts:
91.189.91.39 us.archive.ubuntu.com

I would go with the first workaround, which should solve the issue permanently..
Unless you are somehow being blocked by firewall or router to make outbound connections.


Dual boot (Windows 10 and Ubuntu 19.04) boots straight into Windows

What has worked for me dual booting.
try hitting escape key while booting until you get the boot options menu.
there should be an F9 option to pick the uefi mode.if you installed correctly
ubunu efi boot should be present.from there ubuntu should start.
or F10 bios setup go to boot manager ther should be 2 options windows and ubuntu.
pick ubuntu,and you will boot into grub menu every time.
this is common when installing windows after linux.


First, search for the app called additional drivers in the dash. Open it and wait for it to find any drivers, if it finds any then select any proprietary drivers as they are usually faster.  If nothing happens you should try a more lightweight version of Ubuntu like lubuntu or kubuntu.


Ubuntu 13.04(Raring) doesn't see my Wi-Fi networks

See for help option and for internet connections. My dongle was also not getting started. I saw the help options in mu ubuntu 10.04 it worked.


xinput settings reset in just few seconds

I had something similar. In my case the problem was the mouse disconnecting every few minutes, resetting the configuration. I fixed it by setting up a udev rule by following this answer: Changes with xinput randomly revert back to default


Live USB Stuck at Boot logo on every Distro.

It might be the USB drive. Some USB sticks don't work as liveUSB sticks. I've had some dodgy sticks in the past (especially Kingston ones). Try another USB stick.


How do I contribute a manual testcase to ubuntu?

You have almost everything what you need in a very good tutorial found at this address: QATeam/ContributingTestcases/Manual - Ubuntu Wiki.

There is also a nice video screencast about how to contribute a manual testcase to Ubuntu posted on YouTube: http://www.youtube.com/watch?v=VO7DdlUSt_4. Many thanks to Nicholas Skaggs for this one :)

I will list only the things you need to know before to start:

Launchpad holds the source code for all manual testcases in the manual testcase project. Code contributions are submitted as merge requests.
The QATracker is the master repository for all our our testing within ubuntu QA. It records results and helps coordinate our testing events. Learn more about it here. Code committed to the manual testcase project will be utilized for testing on the qatracker.
Style Guide - a quick review of how the testcases should look and tips to keep in mind while your writing.

And of course, requirements:

bzr (run sudo apt-get install bzr in a terminal to install it).
Launchpad/Ubuntu SSO account

Sources: QATeam/ContributingTestcases/Manual (last edited 2013-02-21 22:18:29 by nskaggs).


Dual boot Windows 8.1 / Ubuntu 14.04 on two separate HDDs

So what I would do is this:

Install both harddrives into your computer.
Format the second harddrive for your ubuntu install while still in windows. It should just show up normally under your drives.
Restart your computer and enter the bios. Disable fastboot and secure boot in the bios.
Boot into ubuntu from a usb or disc.
Install ubuntu under "something else" using this guide. And make sure to install the bootloader to your primary harddrive (the one with windows on it).
Boot from the primary harddrive and it should open GRUB and from there you should be able to choose between your different drives.

Hope this helps!

Side note: I would personally stick with xp or maybe try to get your hands on 7 because 8 is terrible and locks up your computer to make it difficult to install other operating systems.


How can I check if I messed up my encrypted Swap configuration?

If /dev/sda2 has been properly formatted as swap, that change should be all that is needed. If free -m and swapon -s report the swap partition you can assume it is working.


Is there a way to make SWAP partition really like memory for demanding program?

Yes, you can. It doesn’t work exactly as RAM does, but it may help you a lot. There’s a parameter called swapiness. This is the measure of how frequently to use your swap space. A higher value means higher access rates.
More about setting swappiness can be found on the question How do I configure swappiness?

I think you need a higher swappiness rate. But it would be better to add more memory than to increase your swappiness, as this can cause problems for your hard disk drive.


Can this also be done for preferences for applications, such as LibreOffice?

Yes. That is both a good and a bad thing though. If different distributions using the same applications but different versions, sometimes the configuration can be updated so that is no longer backwards compatible with older versions. One example: Banshee is notoriously inflexible when it comes to config versions. If you install a PPA version and try to go back, you have to nuke your config database.

Firefox can get a little twitchy about its plugins if you jump between major versions but it tends to soldier on. And a lot of other applications tend to just work.

But speaking in the wider sense, why would you want to "live" in that many different distributions? I'd go mad trying to remember which I was in and dealing with that many various hardware issues. Yak!

If you just need to do things in the other occasionally, I'd strongly consider leaving your home in your main OS, symlinking/bind-mounting when you need something (like /music), leaving the rest of your profile alone and then just virtualising the less essential operating systems with VirtualBox, XEN or another HV.


Try:

Edit the file /etc/update-manager/release-upgrades .
Change the value of "Prompt" from "normal" to "lts".
Then try sudo do-release-upgrade -d.

See if that works.


Matlab can't find /lib/libc.so.6 in 12.04

What about

sudo ln -s /lib/i386-linux-gnu/libc.so.6 /lib/libc.so.6

Worked for me!

Regards


Here is the solution I found for my problem:

Apparently the ntfs-3g driver used in linux to read and write NTFS partitions was not installed. Please see ubuntu documentation: "Mounting Windows Partitions". After installing the "ntfs-config" package my problem was solved.

Per the ubuntu documentation: "The ntfs-3g packages comes pre-installed in currently supported versions of Ubuntu and most NTFS devices should work out of the box without further configuration (this may not come packaged with 11.10 - Oneiric Ocelot so be sure to check your system if you run into problems with mounting NTFS filesystems after an install or upgrade)."


Accidentally uninstalled most of my programs... help?

Software-center depends on python. you may want to try installing (or reinstalling) the ubuntu-desktop meta package, this should get you back basic essentials,

sudo apt-get install ubuntu-desktop

if it is allready insalled remove it ( sudo apt-get remove ubuntu-desktop ) then install it, don't worry it's a meta package, that is used to install and update a set of packages, What exactly is in ubuntu-desktop?


ubuntu 13.04 failed to start any GUI application as root

I found a an official solution that I like to share with all ubuntuors

when I reviewed application that required root access I noticed they use the following command

su-to-root -X -c

not sudo or gksudo which is strange ( at least for me)

since Ubuntu by default disable root account I enable to enable it using the following command

sudo passwd root

I enabled the root account, then clicked on GUI application ( bleachbit (as root)) to see if it is going to accept the root password and it did :)

finally

I test fresh ubuntu 13.04 installation in a virtual machine and it did not have the same problem as my original machine (my family machine)

it seems there is bug in my system not in the original ubuntu os

I hope this could help some one, and I appreciate any comments or notes


Please read the update at the end of this answer regarding changes in Firefox 52.

Acording to the Firefox developer documentation plugins live here:

Directory pointed to by MOZ_PLUGIN_PATH environment variable
~/.mozilla/plugins
/usr/lib/mozilla/plugins (on non-Ubuntu 64-bit systems, /usr/lib64/mozilla/plugins might be used instead)
Plug-ins within toolkit bundles
[Profile directory]/plugins, where [Profile directory] is a user profile directory

Update for Firefox >=52

As of Firefox 52 support for NPAPI plugins has been dropped. All plugins living in one of the above directories are ignored, with the exception of Adobe Flash.

If you installed Flash with the flashplugin-installer package, it's loaded through a symlink in /usr/lib/mozilla/plugins that ultimately links to /usr/lib/flashplugin-installer/libflashplayer.so.


How do you check systemd update content?

As soon as Major (here it is 229) and Minor (here it is 4)   version numbers does not change, you can install update without thinking about the bug. Maintenance version number (here it is 19) only includes bug fixes.

Also, I suppose that, what you are looking for is Changelog. It will show you what changes are applied in different versions. The output of apt changelog systemd:

systemd (229-4ubuntu19) xenial; urgency=medium

  * debian/extra/units/systemd-resolved.service.d/resolvconf.conf: partially
    revert, by removing ExecStart|StopPost lines, as these are not needed on
    xenial and generate warnings in the journal. (LP: #1704677)

 -- Dimitri John Ledkov <xnox@ubuntu.com>  Mon, 17 Jul 2017 17:00:42 +0100

systemd (229-4ubuntu18) xenial; urgency=medium

  * debian/extra/units/systemd-resolved.service.d/resolvconf.conf: if resolved
    is going to be started, make sure this blocks network-online.target.
    (LP: #1673860)
  * networkd: cherry-pick support for setting bridge port's priority
    (LP: #1668347)
  * Cherrypick upstream commit to enable system use kernel maximum limit for
    RLIMIT_NOFILE isntead of hard-coded (low) limit of 65536. (LP: #1686361)
  * Cherrypick upstream patch for platform predictable interface names.
    (LP: #1686784)
  * resolved: fix null pointer dereference crash (LP: #1621396)
  * Cherrypick core/timer downgrade message about random time addition
    (LP: #1692136)
  * SECURITY UPDATE: Out-of-bounds write in systemd-resolved (LP: #1695546)
    - CVE-2017-9445
  * Cherry-pick subset of patches to introduce infinity value in logind.conf
    for UserTasksMax (LP: #1651518)

 -- Dimitri John Ledkov <xnox@ubuntu.com>  Wed, 05 Jul 2017 13:45:48 +0100


sudo apt-get install apache2-dev command will install dev packages.

Please note that the yum is a package manager for RedHat, Fedora etc.
Equivalent package manager for Ubuntu/Debian is an APT.
Look about apt-get command here: Package Management


Wireless Broadcom adapter is not working in Ubuntu 14.04 with kernel 4.2

It looks like the Broadcom driver was not updated for kernel 4.2, or you never updated your system. Anyway you can install it this way:

wget http://mirrors.kernel.org/ubuntu/pool/restricted/b/bcmwl/bcmwl-kernel-source_6.30.223.248+bdcom-0ubuntu7_amd64.deb
sudo dpkg -i bcmwl-kernel-source_6.30.223.248+bdcom-0ubuntu7_amd64.deb


Configuration is not saving after reboot

Try to start it with gksu amdcccle instead. You should never start graphical applications with sudo, maybe that's the problem.
Also, can't you simply run it as a normal user (without sudo nor gksu)?
Good luck!


Pencil and Pencil Project Package Naming Conflict

This issue still remains in Ubuntu 14.04 though it would appear that the pencil 2D animation may have changed the package name - see https://www.pencil2d.org/

Edit: It appears the naming conflict was resolved on Dec 8, 2016. Detail is here.


Yes. The technology for that is called VNC.
https://en.wikipedia.org/wiki/Virtual_Network_Computing
However, you will have to leave your Windows PC running over the night. An alternative to VNC is RDP.

I also believe this here might help you as well:
Is it possible to use remote desktop from Windows 7 to Ubuntu?


Set default BIOS settings. For that, you have to open BIOS menu and there you will have the option "Reset to default settings". Select that, then save and quit.
Then you will be able to boot in hopefully.


After Win10 upgrade Ubuntu graphics not working in VM

This sounds just like what I am seeing, also Win 10 host, Ubuntu 18.04 guest, and VMWare Workstation Pro v12. Mine seemed to start after an Ubuntu update.

This question described the problem I saw

And the answer that worked for me was to set WaylandEnable=false as described here


How to clean up/clean out /dev/sda7 when permission is denied?

You should be able to boot into recovery mode.  This is a special mode where you log in as root, have only a terminal, and start with read-only access to the drive (which you can then convert to read-write access).

Follow the instructions here:

https://wiki.ubuntu.com/RecoveryMode

In particular, press and hold Shift when Ubuntu is booting, select Recovery mode from Advanced Options, then when prompted, Drop to root shell prompt.

You enable read/write access to the drive with mount -o remount,rw /


Ubuntu 16.04. Synaptics touchpad features stop working

I had the same problem after upgrading to 16.04.  First thing I did was look for the synaptics config file in /etc/X11 but I don't see it anymore.  So I did this:

sudo mkdir /etc/X11/xorg.conf.d
cd /etc/X11/xorg.conf.d
sudo cp /usr/share/X11/xorg.conf.d/50-synaptics.conf  .

That didn't really help any.  So that step might be totally unecessary.

After that I noticed something disabled my touchpad.  To fix, I did this:

synclient TouchPadOff=0

After rebooting this didn't seem to be a problem any more.


Is there anyway to contact whoever handles commercial apps for the Software Center?

As far as I know the contact form is your best bet. It normally takes some time to get a reply though as Canonical does not yet seem to have the capacity to answer such detailed questions quickly, but you should be able to get a response through the contact form eventually.


Command "ps -a" does not show all processes?

It is soffice.bin you are looking for.

With and without "calc" open:

$ ps -A | grep office
 6718 ?        00:00:00 soffice.bin
$ ps -A | grep office
$


Like other users, I'm slightly concerned by the age of the operating system. Is there a good reason you're not upgrading to something that is still officially supported?  Neither 9.04 or 9.10 is so you're not getting security updates.

If there isn't a good reason, I would suggest a clean install of a supported version. Newer the better but 10.04 will be supported for a while still if you're determined to run something old. Assuming you have data you want to save, here's what I would do:

Back up. I'm not going to labour the point but nobody likes data loss.
Boot into your LiveCD.
Using gparted, create a new partition and copy any data you want to keep safe there from your other partitions. This will probably include portions of /home amongst other stuff, depending on what you use the box for.
Nuke your existing install partitions, leaving the newest partition we just copied data to.
Load the installer, do a nice fresh install. When you reboot into the new install you can copy back all your old data.

I'm really just thinking about time. Accurately fixing things by strategically removing partitions isn't guaranteed to fix your problem and you'll still be on 9.10.

Downloading/burning a new ISO, backing up files and doing the fresh install doesn't take that long and you can be doing other things while they progress. And you end up with a nice fresh install of something new.


avconv creates zero byte file while trying to downsample mp4 video

During this conversion both video and audio need to be decoded from the original file and then encoded to the target file. In this case the original file happens to have the audio encoded with 'aac' (Advanced Audio Coding). The decoding of the audio is not a problem, only encoding to 'aac' encoded audio seems to be problematic.

See the last two lines of the output above:

encoder 'aac' is experimental and might produce bad results.
Add '-strict experimental' if you want to use it

As stated in the message the encoder 'aac' is experimental. To use it anyway add '-strict experimental' like this:

avconv -i input.mp4 -s 640x480 -strict experimental output.mp4

This will use the experimental encoder to produce a video with embedded audio which is encoded with 'aac'. If the parameter is omitted no output is created (only a zero byte file). So, no encoder is used in that case.
I was able to convert a video like that with no problem. If the codec does not work for you, you can specify an other codec for audio like that (using mp3 as an example):

avconv -i input.mp4 -acodec mp3 -s 640x480 output.mp4

If is no audible soundtrack in that recording at all - since you are converting a time lapse - you might not want to embed audio at all. To achieve this use the parameter -an:

avconv -i input.mp4 -an -s 640x480 output.mp4


Conky program is not installed on ubuntu16.10

You can get it from the repository in launchpad shared by yourself.

Or simply download the .deb file (v.2.4 )for a 64bit Ubuntu install, here.

More information on the owner's website:

http://www.teejeetech.in/p/conky-manager.html


Certain keys on my keyboard click other keys

You are probably using a different keyboard layout. Check which one you are using on settings and then switch to the relevant one.


How to build ATI Crimson driver on Ubuntu 15.10

I had the same problem and solved it by following the instructions from this page. The page is written in spanish, but all the commands are in english, so it's pretty straightforward.

According with this page, there is a bug in the Ubuntu/wily AMD installation script. That's why you can't install the new driver.

Just to warn you, the command

sudo ./amd-driver-installer-15.30.1025-x86.x86_64.run --buildpkg Ubuntu/wily

may take some minutes to finish, so don't think that the terminal is frozen.

And there's also a little mistake in the command

sudo dpgk -i *.deb

The correct command is

sudo dpkg -i *.deb

Hope that it helps!


Cannot Restore Grub After Windows 8.1 Upgrade

It looks like you have run Boot-Repairs 'buggy' UEFI fix. I thought then you only could boot grub/shim. That renames the Windows efi file to a backup name and renames Windows file to actually be grub/shim.

To undo & to rename files to their original names, you just need to tick the "Restore EFI backups" option of Boot-Repair.

With the renamed file you cannot directly boot Windows from UEFI menu as it really is shim.
And a Windows update may rewrite the bootmgfw.efi file overwriting the shim version, so then if you can only boot the Windows version you have to rerun boot repair. If you can boot Ubuntu entry in UEFI menu, undo the rename.

Boot-Repairs rename copies this /EFI/microsoft/boot/shimx64.efi to bootmgfw.efi
Actual Windows boot file, originally bootmgfw.efi, becomes this:
/EFI/Microsoft/Boot/bkpbootmgfw.efi

Also grub does have a bug and will not boot Windows 8.1 from grub menu with secure boot on.

UEFI NVRAM boot entries are cached in the BCD store
BCD has 1:1 mappings for some UEFI global variables
Any time {fwbootmgr} is manipulated, NVRAM is automatically updated

Alternative to Boot-Repairs rename of shim.
Some systems work better to register grub/shim from inside Windows - for those that keep resetting Windows as default

Grub not showing on startup for Windows 8.1 Ubuntu 13.10 Dual boot

bcdedit /set {bootmgr} path \EFI\ubuntu\grubx64.efi

https://coderwall.com/p/vfyqkg


The issue could be your builtin CMOS does not count time during Ubuntu suspend. It is also interesting, what time is in bios after some time your laptop is being powered off.

To find out what happened it is desirable to know what your system says about it.

For example, you could use the next command to find out what is going on when you sleep/resume your system:

$ sudo journalctl -f | grep sync
бер 09 17:58:41 lenovo kernel: Filesystems sync: 0.190 seconds
бер 09 17:59:43 lenovo kernel: Filesystems sync: 0.143 seconds

To see more detailed output, you could hit in the terminal:

$ sudo journalctl -f

Then close the laptop's lid for some time and then open it.

After that you could examine what is going on on the background and show it here.

To workaround your issue, new systemd service could be created which will synchronize date forcefully by restarting your time service just after suspend, as it described here: https://superuser.com/a/1529040/1032713


Correct way to apply WiFi mac address randomization

The author metioned to change the file in /usr/lib/NetworkManager/conf.d and NOT in /etc/NetworkManager/conf.d

... if you are a distributor or install the file as part of the installation. User configuration should be in /etc.

  I edited the file no-mac-addr-change.conf from -

Here too: as a user, you best don't edit files in /usr. Instead, place the file in /etc/NetworkManager/conf.d, and overwrite the setting. Configuration files are read in a certain order (as documented in man NetworkManager.conf). Files read later amend/overwrite previous settings.

The file /usr/lib/NetworkManager/conf.d/no-mac-addr-change.conf disables changing the MAC address for certain drivers, because the driver doesn't support it. So, unless you have one of these device types, the file had no effect for you to begin with, and adding to the section has no effect either. See the match-device part.

Note that the file disables changing the MAC address for certain drivers because the drivers don't support it. What gives GENERAL.DRIVER in nmcli -f all device show wlp2s0 for you? If you have one of the listed drivers, it may not work even if you configure it in NetworkManager.

In general, look at the logfile of NetworkManager. See the comment in NetworkManager.conf about how to enable debug logging. You should see if NetworkManager fails to set the MAC address of the device (and whether it tries to do so in the first place).

Also, putting wifi.cloned-mac-address= in the [device*] section has no effect. See man NetworkManager.conf. This belongs to a [connection*] instead.

But note the settings under [connection*] only take effect if the corresponding value is not specified in the per-profile setting. For example, if your profile is called "My Wi-Fi", then nmcli connection show "My Wi-Fi" will show you the per-profile wifi.cloned-mac-address that is used. The fallback from the configuration file is only consulted if the per-profile value is unset. So, usually, you would not set the default value in NetworkManager.conf, but instead per-profile with
nmcli connection modify "My Wi-Fi" wifi.cloned-mac-address random.

TL;DR:

   nmcli connection modify "$PROFILE" wifi.cloned-mac-address random
   nmcli connection up "$PROFILE"

   # verify
   nmcli device
   ip link


Ubuntu freezes/crash after wake when upgraded to 13.10

Actually there is a bug which you can find in Launchpad.net

Best thing is that there is also a patch through which you can solve this issue.

Follow these steps hope it works for you also:

Open terminal and execute these steps:

sudo cp /etc/default/grub /etc/default/grub_back

 taking the backup of original /etc/default/grub file, in case some error occurs we can get back to original state

sudo gedit /etc/default/grub

 opening the file in gedit to make the changes.

Once file opened replace following line :

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

to the line:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash pcie_aspm=force"

Save the file Ctrl+S and close Ctrl+Q

Note: The next line to the line mentioned above should be GRUB_CMDLINE_LINUX="" not GRUB_CMDLINE_LINUX="acpi_osi=Linux"

Now execute following command to update the grub

sudo update-grub

Re-start your system once.

Note: If you have trouble in brightness also and above method doesn't fix it then you can test by adding these lines in place I mentioned above.

2. GRUB_CMDLINE_LINUX_DEFAULT="quiet splash nomodeset"

or

3. GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor pcie_aspm=force"

or

4. GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor"

or

5. GRUB_CMDLINE_LINUX_DEFAULT="pcie_aspm=force"

or

6. GRUB_CMDLINE_LINUX_DEFAULT="quiet splash pci=nomsi"

Note: You have to do a sudo update-grub and a system restart every time you change the grub file

Different system would need different options, if any of the option works, I request to mention that in the comment.

Reply if something goes wrong..


How do I flash Snappy Ubuntu Core onto a BeagleBone Black's eMMC?

The result and remaining problem
This walkthrough boots Snappy Ubuntu Core from the Beaglebone Black's(BBB) eMMC instead of the default boot from SD card. But for that to work, it breaks the a/b fallback mechanism constructed in the U-boot step of the Snappy Core default image.
The reason the fallback mechanism is broken is because it uses the "saveenv" U-boot command which for an still unknown reason doesn't seem to work on the BBB's eMMC.

The walkthrough

Create bootable sd card to dd the Snappy Core img to the eMMC of the BBB.

Download the latest Debian image provided by the beaglebone.org:

  $ wget https:// debian.beagleboard.org/images/bone-debian-7.8-lxde-4gb-armhf-2015-03-01-4gb.img.xz

Unpack and copy the debian image to your SD card.
BE CAREFUL you can overwrite your root filesystem if you pick the wrong device! Check "dmesg | tail" when inserting SD card find the correct device.

  $ unxz -c bone-debian-7.8-lxde-4gb-armhf-2015-03-01-4gb.img.xz | sudo dd of=/dev/sdX bs=32M
  $ sync

Overwrite the eMMC default image with the Snappy Ubuntu Core image.

Download a compressed Snappy Ubuntu Core image on the SD Card.
Insert the newly created Debian SD card in the BBB and boot from it using the boot button. Once booted, download the Snappy Ubuntu Core compressed image to the sd card.

  $ wget http://releases.ubuntu.com/15.04/ubuntu-15.04-snappy-armhf-bbb.img.xz

Find out which device is the eMMC.
During boot, the debian image will mount the root filesystem from the SD card to "/".  Usually this is "/dev/mmcblk0".

  $ cat /etc/fstab | grep mmc
  /dev/mmcblk0p2 / ext4 noatime,erros=remount -ro 0 1

Check which is the other available mmc device. Usually this means the eMMC is /dev/mmcblk1.

  $ ls /dev/mmcblk?
  /dev/mmcblk0 /dev/mmcblk1

Unpack and dd the Snappy Ubuntu Core image to the eMMC of the BBB.

  $ unxz -c ubuntu-15.04-snappy-armhf-bbb.img.xz | sudo dd of=/dev/mmcblk1 bs=32M
  $ sync

Change the U-Boot settings to boot from eMMC instead of SD card.
By default U-boot will not boot since the U-boot environment is still pointing to the SD card. I used the uEnv.txt example to get started and adjust a few things in order to point to the eMMC.
Actually 3 lines are changed:

Change the mmc device from SD card (1) to eMMC (0)
Original
mmcdev=0
New:
mmcdev=1
Change the snappy_ab fallback system to snappy_kernel=a, which is now fixed at the first rootfs (a).
Original
snappy_ab=a
snappy_boot=if test "${snappy_mode}" = "try"; then if test "${snappy_trial_boot}" = "1"; then setenv snappy_os "${snappy_good_os}"; setenv snappy_kernel "${snappy_good_kernel}"; saveenv; else setenv snappy_trial_boot 1; saveenv; fi; fi; run loadfiles; setenv mmcroot /dev/disk/by-label/writable ${snappy_cmdline} snappy_os=${snappy_os} snappy_kernel=${snappy_kernel}; run mmcargs; bootz ${loadaddr} ${initrd_addr}:${initrd_size} ${fdtaddr}
New
snappy_kernel=a
snappy_boot=run loadfiles; setenv mmcroot /dev/disk/by-label/system-${snappy_kernel} ${snappy_cmdline} snappy_os=${snappy_os} snappy_kernel=${snappy_kernel} rootfstype=ext4; run mmcargs; bootz ${loadaddr} ${initrd_addr}:${initrd_size} ${fdtaddr}

Remove the SD card and reboot


Install Ubuntu 13.04 alongside Windows 8

Install your Windows 8, then using the USB or DVD for Ubuntu 13.04, install 13.04. You will have the option of installing them alongside each other, use that option. Afterwards, when you boot you will get a boot menu asking which OS you want to boot to...

I use a dual boot on one of my machines, Mint 14.1 and Ubuntu 13.04. I get people set up in either one depending on the person and I have to be able to refer to either while teaching the systems. My main machine uses Ubuntu 12.04...


Install Ubuntu on efi machine with windows 8 preinstalled (possibly remove windows 8)

Do not create partitions with Windows partition tools. Use Windows only to shrink NTFS partitions to make room for Linux formatted partitions. Windows may convert even with gpt partitioned drives to dynamic partitioning which does not work with Linux. With gpt dynamic may also be called LDM.

Are both drives partitioned with gpt not MBR? UEFI needs gpt partitioning to boot although Linux will boot from gpt partitioned drives in BIOS mode. Windows only boots from gpt partitioned drives with UEFI.

While  system will boot only from one efi partition, with two drives it is worthwhile to manually partition and include an efi partition on every drive. Grub is installed to the efi partition of the drive you boot from. But with multiple drives, one drive can eventually fail and if you have boot loader also in other drive (and current) you can change UEFI/BIOS to boot second working drive.

With UEFI, grub2's bootloader is installed to the efi partition. Only with BIOS installs do you install grub2's boot loader to the MBR of the drive or sda (or sdb).
Each system you install should create a folder in the efi partition with it boot loader. With Ubuntu and multiple installs you may only have the most current install in the ubuntu folder and use the grub menu to choose other installs.


unable to install ubuntu in my gatewaylt41p07u

I guess you have iso image of ubuntu. I recommend using Unetbootin software to create bootable usb stick. This software is pretty straight forward and does not need to be installed on system if you are currently on windows. It is also available on Linux.

After bootable USB is created, you can boot your system from this usb by changing bios boot order.

Make sure you have backed up all your important data to external partition(D,E,F etc) or external hard drive. Please refer to ubuntu installation guide before proceeding to start.

I hope it helps.


What can be done to increase my Ubuntu's speed?

Use some other distribution or other desktop interface.

Unity is resource hungry.

Try using lubuntu, xubuntu or mint with mate desktop.


how do i move a file from downloads folder to opt folder?

Go to your download files with this command:

$ cd ~/Downloads

Then run this command to copy the file to the /opt directory:

$ sudo cp john-1.7.9.tar.gz /opt/

By the way, you are most likely getting the error file not found error message because you don't have a downloads directory.  You have a Downloads directory.  The files and directory names in Linux are case sensitive.  Those are two different directory names.  You can have two different folders by those names on Linux, but they would be the same directory in Windows.

Also, in the future when you have a problem copy exactly what you type and the exact error message and paste it to your question.  This would make it easier for the community to see the exact problem.

Please, also consider formatting your quoted text with a one of the formatting provisions such as the '' or the {} tools above.  You can do this by highlighting the text you want formatted then clicking on one of the markdown links.

Detailed explanation of the specific errors

After the reformatted text of your question it's clear that you have two errors.  One of your errors is the misspelling of your downloads folder name.  You specified "downloads" where no folder or file by that name exist.  It should have been Downloads (with the capital D).  The first of your two errors is saying you don't have a "downloads" folder.

The second of your two errors is that you have a space in your pathname.  The space is indicating that you are trying to copy two files, one called /home/kevsfernandez/downloads and one called ‘john-1.7.9.tar.gz’ to your /opt/ folder.

When you specify more than one two arguments, all except the last argument is a list of files to be copied to the last argument.

The answer I gave above resolves the problem.


Lightdm is not changing background on Ubuntu 18.04

https://wiki.ubuntu.com/LightDM

create /usr/share/glib-2.0/schemas/10_unity_greeter_background.gschema.override

with content

[com.canonical.unity-greeter]
draw-user-backgrounds=false
background='/foo/wallpaper.png'

And run sudo glib-compile-schemas /usr/share/glib-2.0/schemas/ to apply these settings.

Adjust to your needs.


How do I make a custom Ubuntu ISO for fully offline installations?

Test this:
Customise the Ubuntu Desktop CD
Install the needed tools

sudo su

apt-get install squashfs-tools genisoimage

Download an official Desktop CD from http://releases.ubuntu.com/
Copy it into an empty directory

mkdir ~/livecdtmp

mv ubuntu-14.04.1-desktop-i386.iso ~/livecdtmp

cd ~/livecdtmp

Mount the Desktop .iso

sudo su

mkdir mnt

mount -o loop ubuntu-14.04.1-desktop-i386.iso mnt

Extract .iso contents into dir 'extract-cd'

sudo su

mkdir extract-cd

rsync --exclude=/casper/filesystem.squashfs -a mnt/ extract-cd

Extract the Desktop system & the SquashFS filesystem

sudo su

unsquashfs mnt/casper/filesystem.squashfs

mv squashfs-root edit

Prepare and chroot

sudo su

cp /etc/resolv.conf edit/etc/

cp /etc/hosts edit/etc/

mount --bind /dev/ edit/dev

chroot edit

mount -t proc none /proc

mount -t sysfs none /sys

mount -t devpts none /dev/pts

export HOME=/root

export LC_ALL=C

Customizations
Before installing or upgrading packages you need to run

dbus-uuidgen > /var/lib/dbus/machine-id

dpkg-divert --local --rename --add /sbin/initctl

ln -s /bin/true /sbin/initctl

Remove, install & upgrade packages.

If you've modified the kernel, init scripts or added new kernel modules, you need to rebuild the initrd.lz file and substitute it into the casper directory.

sudo su

chroot edit mkinitramfs -o /initrd.gz 3.13.0-25-generic

(replace the kernel version with the one that the CD will boot with - this can be found in edit/lib/modules)

Exit from the chroot jail and move this file to extract-cd/casper:

exit

mv edit/initrd.lz extract-cd/casper/

Remove any temporary files which are no longer needed.

apt-get clean
Or
rm -rf /tmp/* ~/.bash_history

If you installed software, be sure to run

rm /var/lib/dbus/machine-id
&
rm /sbin/initctl

dpkg-divert --rename --remove /sbin/initctl

Unmount special filesystems and exit chroot

umount /proc || umount -lf /proc

umount /sys

umount /dev/pts

exit

sudo su

umount edit/dev

Producing the CD image and compress filesystem

sudo su

chmod +w extract-cd/casper/filesystem.manifest

chroot edit dpkg-query -W --showformat='${Package} ${Version}\n' > extract-cd/casper/filesystem.manifest

cp extract-cd/casper/filesystem.manifest extract-cd/casper/filesystem.manifest-desktop

sed -i '/ubiquity/d' extract-cd/casper/filesystem.manifest-desktop

sed -i '/casper/d' extract-cd/casper/filesystem.manifest-desktop

rm extract-cd/casper/filesystem.squashfs

mksquashfs edit extract-cd/casper/filesystem.squashfs -comp xz -e edit/boot

printf $(sudo du -sx --block-size=1 edit | cut -f1) > extract-cd/casper/filesystem.size

nano extract-cd/README.diskdefines

cd extract-cd

rm md5sum.txt

find -type f -print0 | sudo xargs -0 md5sum | grep -v isolinux/boot.cat | sudo tee md5sum.txt

mkisofs -D -r -V "$IMAGE_NAME" -cache-inodes -J -l -b isolinux/isolinux.bin -c isolinux/boot.cat -no-emul-boot -boot-load-size 4 -boot-info-table -o ../ubuntu-14.04.1-desktop-i386-custom.iso .

Burning the image to CD

cdrecord dev=/dev/cdrom ubuntu-14.04.1-desktop-i386-custom.iso


Using grub4dos to boot Ubuntu Ubuntu 18.04 ISO disk image, here is the entry for the file MENU.LST:

title Ubuntu 18
  fallback 6
  find --set-root /iso/ubt1804.iso
  map --heads=0 --sectors-per-track=0 /iso/ubt1804.iso (0xff)
  map --hook
  root (0xff)
  kernel /casper/vmlinuz file=/cdrom/preseed/ubuntu.seed boot=casper iso-scan/filename=/iso/ubt1804.iso splash
initrd /casper/initrd.lz

NB,

For Ubuntu 64bit from 14.04 to 17.10  vmlinuz.efi was used, so kernel has to be /casper/vmlinuz.efi, but
For older versions and 18.04+ use /casper/vmlinuz
For Ubuntu 32bit, it has always been vmlinuz
For smaller ISO disk images, or your RAM is extremely big, you can use --mem for the map command to put the whole disk into system memory, like this:
map --mem /iso/smallcd.iso (0xff) || map --heads=0 --sectors-per-track=0 /iso/smallcd.iso (0xff)

Ref: here


youtube-dl keep both auto-generated subtitles and prewritten ones

The other answer is wrong and actually misleads and wastes people's time with this "latest version" thing which is an issue on his end and has nothing to do with the question...

The actual answer is that youtube-dl names its subtitle files only with the language in it (ex: file.en.vtt), which means that a potential auto-en would be named the same way as en, hence the resulting rule that real subtitles will always be prioritized over auto subtitles if both are asked for in the command. This is something that needs to be asked of the devs if we want to be able to do it with youtube-dl alone.

Source :

https://github.com/ytdl-org/youtube-dl/issues/1412

  Done, but currently --write-sub --write-auto-sub --all-sub would
  download en, fr, auto-es. Downloading both en and auto-en would
  require creating a new field in info dicts for automatic captions.


Use a terminal as desktop background instead of the wallpaper

Well that's an interesting problem.

This is quite simple in KDE, you just set up a special window assignment (right click the title bar) to make the terminal fullscreen, below all other windows, drawn without window decorations and to skip the taskbar. It works beautifully.

Under Compiz you can achieve a similar effect with CCSM with its Window Rules plugin. The problem you have is differentiating between a terminal you might load up subsequently and the one you load on boot. It might make sense to install another terminal application (Terminator is a fine choice) and just use that for your desktop. Then you can tell CCSM to change the window settings on all Terminator instances.

In both cases you can leave the desktop as it is. It'll be there, but it'll be obscured by the terminal.

Another way you could do this (using the same ideas as above but cross-platform) is to use wmctrl to set the hints rather than leaving it up to the Window Manager.

The following three commands will set the current window to cover the desktop.

wmctrl -r :ACTIVE: -b add,fullscreen
wmctrl -r :ACTIVE: -b add,below
wmctrl -r :ACTIVE: -b add,skip_taskbar

You can either save that in a script or you can munge it all together in a lovely messy one-liner. Annoyingly, wmctrl can only do two hint changes at a time so it's a little more bloated than one might like.

gnome-terminal -x sh -c "wmctrl -r :ACTIVE: -b add,fullscreen,below;wmctrl -r :ACTIVE: -b add,skip_taskbar;bash"

Other terminal emulators will work like this but they might have a different argument for running something (vs the -x that gnome-terminal and terminator use). konsole uses -e, for example.


Access application's private environment variables and shell

As already answered on comments by our friends

sudo cat /proc/$(pgrep gedit)/environ | tr '\0' '\n'

References:

how-to-read-environment-variables-of-a-process
how-do-i-split-a-proc-environ-file-in-separate-lines

But it is not worth much as all classic GUI app run same environment accept when user customize a desktop launcher or script and modified it. Which is not the case with snaps.


Is there a Kdenlive PPA for Ubuntu trusty or how to use a PPA for a different version of Ubuntu?

As you can see from the link, Kdenlive is available via the default Ubuntu 14.04 repository.  If you are having problems with the default installation, you might consider posting a description of the problem which might be resolved by some workaround with some of the codecs or other system libraries and utilities that are part of Trusty.

A ppa provided for an earlier version might be more compatible than a ppa provided for a later OS version, because newer OS' often comes with upgraded components (libraries and functions) that might not be totally compatible with a previous version of Ubuntu.  Trying to update each library with to make your installation compatible to a later OS might take more work that you would anticipate than just upgrading to the later OS, which you have already specified that you are not ready to do.

You can, alternatively, review the daily built page that includes very up-to-date links to kdenlive tarballs:
Kdenlive Daily Builds

When installing packages from tarball you usually have a choice of alternate location install, which allows you to either run your daily built install (which might have some glitches) or the official release, separately.

The packages I install from tarball or from compiled source, I install in a subdirectory of /opt.

As mentioned above, I'm certain that you'd experience more work trying to fix incompatible libraries and modules using a later ppa than you would have in upgrading your OS where you would have full support for your OS by upgrading.

Just looking at the fact that they don't maintain the current 14.04 LTS in their ppa support makes it appear there might be compatible issues that they are not prepared to deal with.  I'm sure it would be ideal to have automatic updates, but the only automatic updates they are providing (as you see) is the ones provided in the repository.


adjusting screen brightness Skylake+Nvidia

Try seeing if Xorg is detecting the keys as brightness changers.

Use evtest to see what the currently pressed key is reported as:
    sudo evtest
Select the number of your keyboard's input (ie. /dev/input4, you'd select 4)
Then try pressing your buttons, it should return something similar to this:
Event: time 1459134230.421349, -------------- SYN_REPORT ------------
Event: time 1459134230.526008, type 4 (EV_MSC), code 4 (MSC_SCAN), value f8
Event: time 1459134230.526008, type 1 (EV_KEY), code 225 (KEY_BRIGHTNESSUP), value 0
If the buttons are reported as something different, then you can just add the buttons as custom shortcuts in the Settings menu. The commands to raise and lower brightness are xdotool key XF86MonBrightnessUp and xdotool key XF86MonBrightnessDown respectively.

Also another random question, how did you get the nvidia-364 drivers to install and work correctly on your laptop? Everytime I try to install them on mine (i7-6700HQ and GTX970M same as you) it whines about not finding a compatible driver in the Xorg logs (it gets stuck in the login loop)


How to solve the DJANGO_SETTINGS_MODULE error?

DJANGO_SETTINGS_MODULE.

function setdsm() {
    # add the current directory and the parent directory to PYTHONPATH
    # sets DJANGO_SETTINGS_MODULE
    export PYTHONPATH=$PYTHONPATH:$PWD/..
    export PYTHONPATH=$PYTHONPATH:$PWD
    if [ -z "$1" ]; then
        x=${PWD/\/[^\/]*\/}
        export DJANGO_SETTINGS_MODULE=$x.settings
    else
        export DJANGO_SETTINGS_MODULE=$1
    fi

    echo "DJANGO_SETTINGS_MODULE set to $DJANGO_SETTINGS_MODULE"
}

put this in  .bash_profile, then a quick setdsm sets the DJANGO_SETTINGS_MODULE to the settings.py in the current directory and add the current directory and it’s parent to PYTHONPATH.

Taken from: http://www.juiceanalytics.com/writing/django_settings_module/
Check this also: http://martinjansen.com/2008/10/20/django-settings-files-for-development-and-production/

Hope this helps.


How to add a system call to the Linux Kernel?

Ubuntu doesn't do anything special. Your first difficulty is that you don't have the kernel source installed, only kernel headers. The authors are describing a system with a copy of the kernel source in /usr/src/linux-2.x. If you're only compiling external modules, the headers, which are what you see on your system, are enough. Ubuntu ships kernel headers for that purpose in the linux-headers-* packages (which you would normally install via the dependency from the linux-headers-generic  metapackage). If you need the whole source, get a compressed archive from the linux-source-2.6  binary package.

Another thing is that the directory structure has changed a little over time; architecture-dependent headers moved from include/asm-$ARCH to arch/$ARCH/include/asm. Furthermore the i386 and x86_64 architectures were merged into a unified x86 in 2.6.24. (More details here.) So you now need to look in arch/x86/include rather than include/asm-i386.

Here are a few useful resources for Linux kernel hackers:

Linux Device Drivers (LDD3)
LWN (news about Linux, including many technical articles about the kernel by one of the authors of LDD)
LXR to browse and search the kernel source
LKML (the Linux kernel mailing list), Stack Overflow to ask questions about the kernel and kernel development

And also read this thread on Unix & Linux, which explains how to locate the implementation of an existing syscall.


How to restrict the decimal places in awk without rounding off

Using awk

with print

awk -F. '{print $1"."substr($2,1,2)}' filename

or

with printf

awk -F. '{printf "%0.2f\n",$1"."substr($2,1,2)}' filename

Example

$ awk -F. '{print $1"."substr($2,1,2)}' foo
0.74
77.65

$ awk -F. '{printf "%0.2f\n",$1"."substr($2,1,2)}' foo
0.74
77.65

$ cat foo
0.748
77.657


I had this after installation, but it went back to normal after doing a re-boot. That was 3 days ago and it has been ok since then.


Should I use a persitant Linux live or install ubuntu?

First, is your home laptop already running Windows? If yes, and if you want to keep Windows, you'll need to set it up on dual boot, which with UEFI might be tricky for a beginner.

For your project, a Live Linux USB stick might be sufficient.  The advantage is that you won't have to worry with installations and fear of data loss (again, assuming your laptop runs Windows).  Just remember to do regular backups on another disk...

Another option would be to install VMware and then create an Ubuntu VM on it.  In this way you'll be free to experiment whatever you want.


What is the named daemon and why is it running?

/usr/sbin/named is provided by the bind9 package. bind9 is a DNS server. If this is a VPS, it's quite possible you need that package. But you can probably remove it and see what happens, and then put it back if you need it.

sudo apt-get remove bind9

The removal might want to remove other packages, including quite important ones for you. So make sure to pay attention to that before proceeding with the removal. This may also reveal why bind9 is installed--it may be a dependency of other packages that you are using.

Please note that I'm not saying you should be doing this--only that you probably can, if you want. If you do this, then even if the server stops working properly, you'll probably still be able to access the Internet to download and reinstall the package. However, it's possible that you will not be able to, or that you will not be able to re-SSH to the server if your connection gets broken. (Thanks to tgm4883 for pointing this out.)

You can substantially mitigate the risk of problems by making sure you have the necessary .deb files cached to reinstall bind9 and its dependencies:

sudo apt-get --download-only --reinstall install bind9

If you've run that recently, and not run sudo apt-get clean since, then you should be able to reinstall bind9 even if you cannot connect to the Ubuntu download servers after removing it:

sudo apt-get install bind9

You may need to run sudo apt-get update before either of the above two commands.

If you don't want to remove bind9 at all, but just see what would be removed if you did (which may reveal why it's installed), you can simulate its removal:

apt-get -s remove bind9


Why do I have to authenticate again with password after having logged in with fingerprint?

Using the fingerprint reader for login never decodes your password ring, which would be necessary for some other things like email.  The password ring is encoded with your password, so that's what's needed for the decode.  Unfortunately, that makes fingerprint login less useful than you might like.


I suggest to check the validity of the web server certificate . The steps you describe are correct, but let's get the facts about the certificate.

The steps below, I use for troubleshooting the web server certificate.

Check if the server name you expect is in the /CN option in subject:

(SERVER_COMMON_NAME is the webserver who you want to contact)

 echo | openssl s_client -servername ${SERVER_COMMON_NAME} \
    -connect ${SERVER_COMMON_NAME}:443 2>/dev/null | \
    openssl x509 -noout -subject

Check if the CA is the one you expect (the supplier of the    cerficate):

echo | openssl s_client -servername ${SERVER_COMMON_NAME} \
            -connect ${SERVER_COMMON_NAME}:443 2>/dev/null | \
        openssl x509 -noout -issuer

Check the /CN field in issuer line.

Check the dates of the certificate

echo | openssl s_client -servername ${SERVER_COMMON_NAME} \
        -connect ${SERVER_COMMON_NAME}:443 2> /dev/null | \
        openssl x509 -noout -dates

Check the 'notBefore' and 'notAfter' results.

If the above looks good, then test with curl AND specifing the CA root certificate file:

curl --cacert certs/the_ca.cert.pem -I https://${SERVER_COMMON_NAME}:443

If --cacert option works then check if the CA-root file is system wide known.

Ommit the --cacert.
If curl gives an error, then the ca-root-file is NOT installed in the system ca-certificates directory.


AR9462 working only from command line and only with WEP

I've been dealing with this issue on the same system (Lenovo Miix 2 11), and it seems to happen on any distribution. Manual configuration works, but apparently Network-Manager (and others) respect the "rfkill" switch. I haven't looked into the airplane key much (still trying to get some version of Linux installed), but I do have a work around:

sudo rmmod ideapad-laptop

It seems like some Yoga models have problems with this module too, so you can look in various forums for "rfkill" "ideapad-laptop". Also, the "acer-wmi" module seems to be loading. I'm not sure this is doing any harm, but the brightness and volume seem to work without it.


Unmet dependencies installing MariaDB 10.1 on Ubuntu 16.04

You can try 'sudo apt-mark showhold' to see which packages might be 'held' ("you have held broken packages"). You could then 'unhold' them with 'sudo apt-mark unhold package-name'.

Generally 'sudo apt-get update' is also a good idea, to make sure your local apt cache knows what is and isn't available.


Openbox : launch a maximize application through ob menu

Here is a way to open all applications maximized when using the Openbox window manager. (I do not know which distro OP is using and so two slightly different routes are suggested.)

For distros other than Lubuntu:
Make a backup of /etc/xdg/openbox/rc.xml for safety
Open /etc/xdg/openbox/rc.xml with a text editor
Go to the bottom of the file. You should see:
    </applications>
    </openbox_config>

Just above the line with </applications>, paste the following:
    <application class="*">
    <maximized>yes</maximized>
    </application>
Save rc.xml
Open a terminal and run openbox --reconfigure. This will make Openbox aware of the changes. If not effective, log out and back in.
From now on, all applications will open maximized.

(Source)

For Lubuntu 12.10 users, edit ~/.config/openbox/lubuntu-rc.xml instead of /etc/xdg/openbox/rc.xml. (I verified this because I'm using Lubuntu 12.10.)

If you decide you don't want all applications to open maximized, but just some specific ones, you will need the following code instead of the one above for each application that you want maximized:
    <application class="......"> (See below)
    <maximized>yes</maximized>
    </application>

Note that the way to find out the application class is via xprop.
You will need to have a terminal window open as well as a window of the application whose class you need to find.
Type xprop _OB_APP_CLASS in the terminal window and press Enter.
Notice the cursor will have changed its appearance to cross-hairs.
Now, using the mouse, click in the window of the application you need.
Then, look back at the output in the terminal. For example, if I run xprop _OB_APP_CLASS and click on a window belonging to Google Chrome, I see: _OB_APP_CLASS(UTF8_STRING) = "Google-chrome" and "Google-chrome", including the quotes, is exactly what should be typed as the application class.
You will need to do this for each application you desire to have open maximized.

One side-effect of <maximized>yes</maximized> is that not just the primary window but other windows open maximized. For example, in Firefox, pressing Alt > Edit > Preferences or Alt > Help > About will result in maximized panes. The same happens in Chrome's Task Manager (Shift+Esc).

If such behavior is undesirable, xprop will need to be run for both primary and secondary windows to see if they can be distinguished.
For the Chrome, Firefox, Opera and Seamonkey browsers, the following code maximizes only the browser window proper and not "internal" windows:
    <application role="browser">
    <maximized>yes</maximized>
    </application>


How to highlight and select text in wsl?

This is a partial answer from this link. If you have a shortcut in your desktop, right click on it, click in properties and then go to the options tab. To activate copy and paste, you need to click copy and paste using ctrl+shift+C|V  checkbox. To highlight text, you need to enable(check mark) the edit mode checkbox. This was tested in WSL in Windows 10.

Note that this  is only a partial solution as this will not work if you start WSL from Windows Explorer. As described in the link above, it depends where you are calling WSL from. Hopefully somebody else adds to this answer. In the meantime, this solution works for me.


Just passed by this post while searching for a similar issue with fan on my Toshiba Satellite L650.

If your problem has not been solved you can try this. This works on my machine perfectly.

Download these two files and place 01_acpi in /etc/grub.d/ and chmod +x it with root privileges. Then place dsdt.aml in /boot and run update-grub2 in terminal.

After rebooting the machine, the battery applet should work fine.

Here are the links to the files.

01_acpi
dsdt.aml


GRUB no longer shows Windows 10 in dual boot menu during Windows update

I'm not sure if the Windows Update overwrote GRUB, but the absence of the boot menu suggests so.

I would try booting into the Ubuntu Live USB and running boot-repair to reinstall GRUB. After booting into the live USB, run

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

Then this should appear, and click "Recommended repair"


Can't connect Google Nexus in Ubuntu 13.04

Try updating mtp?

sudo add-apt-repository ppa:langdalepl/gvfs-mtp
sudo apt-get update

Then, launch Software Updater (previously known as Update Manager) and install the available updates


Laptop overheats and turns off even though the fan runs

Most fan problems I have seen have been due to one of three issues. In order from common to least common they are:

Dirty Fans - Check your fans, make sure they are clean, make sure there is no dust or blockage. Fans work differently in Linux (speed up and slow down at different times) and they assume a lack of garbage in the airflow path. I have seen this lead to overheating.
Bad hardware setup - The Studio 1747 had some problems with it's wireless card at one point. This site seems to indicate it has been fixed, however I have seen some broadcom chips "over heat" and thus push other temperatures up enough to cause a thermal event. Take into consideration any hardware that might heat up and cause other things to heat up.
Wrong fan speed - This is rare, but can happen. Try using fan_control to manually control the speed.  See this posting. Controlling your fans manually should be the last answer, but it is possible.

Make sure to record your final results at Ubuntu Friendly.


How to make sure that a external drive is mounted before copying files to it through a scheduled backup

You should be able to use the exit status of the mountpoint command to determine whether a given path is an active mountpoint or just a regular directory:

$ mountpoint /home ; echo $?
/home is a mountpoint
0

$ mountpoint /var ; echo $?
/var is not a mountpoint
1

So for example you could do something like

if ! mountpoint -q /path/to/backupmount; then
  # attempt to mount the backup drive
  # exit on error
fi

# continue with backup


Keyboard layout - certain keys work with AltGr, other doesn't

I have had the same problem and the solution after a great headache during days has been the following. Nothing can be more easy:
In the option: file->preferences->input
the following check box must be disabled: keyboard autocapture

I am translating from spanish version, but there must be something similar in the english version.
Greetings.


I think you need to purge the others, not only samba before reinstalling.

apt-get purge samba samba-common system-config-samba winbind


Try reinstalling grub on your machine.

Create a bootable ubuntu USB or CD installed. (Same installed release recommended)
Boot from that LIVE USB/CD and install boot-repair :-

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

Then run boot-repair or On dash search for boot repair  and select recommended settings.


You can try to solve the problem as suggested here..

http://ubuntuforums.org/showthread.php?t=1737637

It is likely to be a bad download or a poor burn - please check by doing a ISO check as per the community wiki:  https://help.ubuntu.com/community/HowToMD5SUM


fallocate failed: Operation not supported

If sparse files are ok for you (e.g. you want to create an image in order to populate it with a file system), they are created in no time at all

100GB take 3 milliseconds:

# time dd if=/dev/zero of=tmptst.dat bs=1G seek=100 count=0
0+0 records in
0+0 records out
0 bytes (0 B) copied, 0,00037726 s, 0,0 kB/s

real    0m0.003s
user    0m0.000s
sys 0m0.002s

The resulting file:

# ls -lh tmptst.dat
-rw-r--r-- 1 root root 100G 2015-01-22 16:39 tmptst.dat

Its real size at the moment: 0 Bytes

# ls -lsh tmptst.dat
0 -rw-r--r-- 1 root root 100G 2015-01-22 16:39 tmptst.dat


Uninstalled snap applications still appear in Show Applications?

Finally I know how to solve this problem.

Thanks to this answer here https://askubuntu.com/a/1022504/373365

You have to go to /var/lib/snapd/desktop/applications and remove skype_skypeforlinux.desktop file

That's all.


Installing Ubuntu server without a monitor

Got it fixed, just needed to use ifconfig up


I contacted Zoom support, This was the response,

The Previous version of Zoom did not create this file path, so we have to add it manually by using touch ~/.config/zoomus.conf
That creates the configuration folder and when Zoom runs during install, the files are populated.


The pyjamas package is available for Lucid from this ppa. Although there is no pyjamas-desktop package :/ To add the ppa and install you can do

GUI Method

Open the Ubuntu Software Center, choose the "Edit" menu and select "Software Sources ...". Select the "Other Software" tab in the dialog box and click on the "Add ..." button. Then enter the text "ppa:fabricesp/ppa" and click "Add Source". Then click "Close" and wait for the update to finish. Then you should be able to use the search box to find pyjamas and install it.

Command Line Method

$ sudo apt-add-repository ppa:fabricesp/ppa
$ sudo apt-get update
$ sudo apt-get install pyjamas


How to install Brave web browser for 32-bit lubuntu 16.04?

The accepted answer is obsolete because the Brave browser snap package has been discontinued. The current instructions for installing Brave browser in Ubuntu from the official Brave browser website are as follows. Open the terminal and type:

sudo apt install apt-transport-https curl
curl -s https://brave-browser-apt-release.s3.brave.com/brave-core.asc | sudo apt-key --keyring /etc/apt/trusted.gpg.d/brave-browser-release.gpg add -
echo "deb [arch=amd64] https://brave-browser-apt-release.s3.brave.com/ stable main" | sudo tee /etc/apt/sources.list.d/brave-browser-release.list
sudo apt update
sudo apt install brave-browser


How to suspend Ubuntu after a specific period of idle time?

Just solve the problem, it happens to be some sort of problem with timer of screensaver, i just reduce the time slider in the screensaver for less than 10 minutes and the pc finally suspends on its own.


Mitigating CVE-2016-3115 By Disabling X11Forwarding

If you are accessing server using ssh and PuTTY and using only command-line utilities, you are good to disable X11 forwarding.

X11 forwarding is needed only if you want to run X11 applications (graphical, window) on the remote server and have them displayed on your local desktop.

Also you didn't specify which Ubuntu version you are using, but currently I don't see in changelog, that this patch was backported even to 15.10.


Wi-Fi adapter Realtek RTL8192CU slow speed connection ~0,5 mbit

There's no need to install any drivers from GitHub (it won't work).

The problem is that the system has two drivers. (rtl8xxxu and rtl8192cu)
Old one (rtl8192cu) should be turned off to turn on a new one (rtl8xxxu) that is already built into the Linux kernel.

Let's see it:

lsmod | grep rtl

Let's blacklist the last one:

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

Then restart your system:

sudo reboot


Xrandr message: Rate 144.0 Hz not available for this size

I had the same problem with my 144hz monitor. You might try using a full set of parameters. For example, to get my 2560x1440 screen to operate at 144hz, I had to do the following:

Run xrandr to find the name of your connected display output. In this case, DP-0 is my connected DisplayPort:

$ xrandr
Screen 0: minimum 8 x 8, current 2560 x 1440, maximum 16384 x 16384
DVI-I-0 disconnected (normal left inverted right x axis y axis)
DVI-I-1 disconnected (normal left inverted right x axis y axis)
HDMI-0 disconnected (normal left inverted right x axis y axis)
DP-0 connected primary 2560x1440+0+0 (normal left inverted right x axis y axis) 598mm x 336mm
2560x1440     59.95*+ 144.00   120.00    99.95    84.98    23.97
DP-1 disconnected (normal left inverted right x axis y axis)

Then use the xrandr command again with the --output, --mode, and --rate parameters. For my 2560x1440 monitor, I specified the following:

$ xrandr --output DP-0 --mode 2560x1440 --rate 144.00

The monitor blinks and switches to the new rate. I'm not sure how to properly use the -s parameter.


Webmin is not in any Ubuntu repositories. You will need to download the debian package file (.deb) at http://www.webmin.com/download.html

Their installation instructions for Debian apply to Ubuntu (and include Ubuntu specific notes) at http://www.webmin.com/deb.html


Postgresql error after installation could not connect to server

Try these steps

sudo chown -R postgres:postgres /var/lib/postgresql/9.(your_version_here)/

sudo chmod -R u=rwX,go= /var/lib/postgresql/9.(your_version_here)/

You need to replace the (your_version_here) with your psql version (9.5 most probably).

Source


Tor Browser Launcher does not download Tor Browser

i got the same thing but never explored why or how to fix. I had ubuntu.podcast playing at the moment I got the error where they were talking about the "software boutique", so I gave it a try and presto - i had tor browser installed.  if no-one else can answer as to a fix; you could always try my lazy-ass work-around

[software boutique is a new-ish [ubuntu-mate] ubuntu-software-centre that contains common or best-in-class type apps, skipping many less-used ones]

addendum:  if trying this, un-install current version first; as I was left with two menu items & icons (one for fully-installed by boutique, and other failed by apt-get); so its probably quicker to have none-installed first instead of working out which is which to un-install the partially-installed-one..


Should I use a different user other than the first one that is created during the install in Lubuntu 16.04?

Is the first user you create, when you enter your information during the install, an admin or some kind of privileged user?

Yes. By default, the user you created during the installation is added to the sudoers file and can execute programs with root privileges.

  If not, is there a hidden "admin" account similar to root but with less privileges that is already created?

There is no "hidden admin".

  Should I create a regular user to use for everyday tasks or is it safe to use the first user that is created?

It depends. Although the user created upon installation is granted sudo-permissions, by default privilege escalation prompts the user for her password. This prevents unsolicited privilege escalation and is a reasonable compromise between security and convenience.


Everybody installing N1 in Ubuntu 15.04 or 15.10 have the same problem. You can see here : https://github.com/nylas/N1/issues/156

One "solution" is to install libgcrypt11 from older ubuntu version.

64-OS's

32-OS's

Personally I wouldn't do that. N1 relies on obsolete software and this is not a reason to mess with security packages.

"It should be fixed soon" https://github.com/nylas/N1/issues/269


The PHP code is displayed as raw text instead. This is because your PHP module for Apache isn't installed.

Run the following command:

sudo apt update
sudo apt install php7.0
sudo apt install libapache2-mod-php7.0
sudo a2enmod php7.0
sudo systemctl restart apache2.service

That should make your lamp working well.

Please do take note that php7.0 is the default version for Ubuntu 16.04. You will need to install the latest version of php for future versions.


Compiling things which link to something usually requires something-dev package installed. Do you have ruby-dev installed?

apt-get install ruby-dev

should do the trick


You probably have "Automatic Login" switched to On.  You need to switch this off.

Go To System Settings > User Accounts > [Select unlock]

Then use the toogle switch to turn off "Automatic Logon"

Then
Log out and back in again and the Unity Greeter should be there.

You will be able to select options other than Unity here,


The partition /dev/sda6 cannot be directly partitioned:  it is  inside of the extended partition /dev/sda4, and /dev/sda4 is full.

To increase the size of '/' you will need to:

first increase the size of '/dev/sda4'
Move the new 'unallocated space' inside '/dev/sda4' to become adjacent to (next to) '/dev/sda6'
Increase the size of  '/dev/sda6' to include the free space.

None of this should be done while Ubuntu is running.  Please create a liveUSB, Back up your data, and boot from the liveUSB, selecting "Try Ubuntu" when prompted.  Once booted from the USB you will be able to use gparted to manipulate the partitions on your disk.


For 11.10 and 12.04
For 11.10 and 12.04, you'll need to do this through a terminal.
Open up a terminal (Super, then type Terminal into the dash), then run the following:
sudo apt-get update && sudo apt-get install lubuntu-desktop
Or install via the Software Center:

You will get asked to enter your password, and you will also be asked to choose between LightDM and LXDM - I suggest using LightDM.
Once that is done, log out, and then select Lubuntu as your desktop session:


What version of freetype does Maverick use?


Use custom bitrate / better: bitrate per channel in Gnome Sound Converter (esp. for opus)

You can use WinFF, a gui front end for ffmpeg

sudo apt-get install winff

Open WinFF and then close it again. Open the preferences file located at

~/.winff/presets.xml

add the following section then save the file and reopen WinFF

  <opus>
    <label>Opus</label>
    <params>-acodec libopus -b:a 256k -vbr on -compression_level 10</params>
    <extension>opus</extension>
    <category>Audio</category>
  </opus>

That is set to 256k vbr and ffmpeg seems to convert to 48000Hz by default

If you choose the Convert to: dropdown as 'Audio' in WinFF, the Preset: section will then have an Opus setting to select

You can make as many of the above presets as you like for different bitrates etc, just the outer tags need to be renamed  and the label changed to whatever you want.

The full list of Opus options can be found using

man ffmpeg

To inspect the output install the following

sudo apt-get install opus-tools

then use

opusinfo foo.opus

to look at what you have created.


This problem went away with the update to Ubuntu 19.10.


'libstdc++.so.6: cannot open shared object file: No such file or directory"

Try these commands:

cd /home/drmohammed/workspace/android/android-sdk-linux/platform-tools/

./adb install mobogenie_1028.apk

./adb 'installmobogenie_1028.apk'

What was wrong?

Needed to be cd. You weren't actually changing directory.
You had no space after install and the path. It may have been causing an issue?
You had an extra quote at the end, which was causing the >. Bash was expecting more input.

On top of that, you hasn't changed directories with command 1, so there was no file in that location.

Update. Per the edit, you need this answer:

  libstdc++.so.6: cannot open shared object file: No such file or directory

Run this command:

apt-get install lib32stdc++6

And then the commands I have already said above:

My pronouns are He / Him


As you said

  I'm new to Linux

the answer is simple: Forget it.

Trusty is to old to build the latest GNOME/GTK3 release with jhbuild. Therefore upgrade to the latest Ubuntu release. You could compile each version yourself. But trust me, that's the wrong way for you.

System installed packages which are too old:
    plymouth (ply-boot-client.pc, required=0.8.9, installed=0.8.8)
    gnutls (gnutls.pc, required=3.1, installed=2.12.23)
    libsystemd-daemon (libsystemd-daemon.pc, required=210, installed=204)
    libsystemd-login (libsystemd-login.pc, required=210, installed=204)

You need newer development libraries. In this case, you have to compile it yourself as your are on Trusty.

No matching system package installed:
    libsystemd (libsystemd.pc, required=210)

The library libsystemd-dev isn't available for Trusty. Goto the developer page, download the source code and compile it yourself.


Where can I see the source code of UnZip

To see the source used in the Ubuntu package, go to:

https://code.launchpad.net/ubuntu/+source/unzip

You can also use:

apt-get source unzip

You may need to enable source repositories in your software preferences for the second option.


I got it to work by using a real user/pass instead of guest account.


Try modifying your /etc/default/grub file as following:

Type gksudo gedit /etc/default/grub
Find this line: GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
Change it to one of the following (on my system only the first one worked):

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

Open a terminal (ctrl + alt + T) and type: sudo update-grub
Reboot.


My computer will not boot after an upgrade to Ubuntu 19.10. It used to only work in nVidia Optimus, now it will not boot at all

I have a simlilar issue, happens every time Ubuntu updates system files under 19.10.
I get a purple screen at login without the login prompt. I found out that the Nvidia card at boot switches to a hypothetical second screen, sets it as primary and shows only the secondary. When I move the mouse to the right, the mouse pointer appears coming from the left side of the screen - hence there is a second screen to the left of my laptop that I can't see.
But I can access it, typing

Enter
My password
Enter

and Ubuntu starts normally. the first time it happened it also showed me a blank desktop since also in GUI the primary desktop was the not-connected second screen. Accessing the screen options via shortcut (Fn - Fsomething) restored the single screen. i the changed the screen options to single screen again and I'm safe until the next update.


BTRFS in RAID1 is showing double the disk space

According to https://btrfs.wiki.kernel.org/index.php/Balance_Filters and thanks to comments to my questions, btrfs balance function was the right answer.

$sudo btrfs balance start -v -dusage=0 /mountpoint fixed my problem.

Output:

Dumping filters: flags 0x1, state 0x0, force is off
  DATA (flags 0x2): balancing, usage=0
Done, had to relocate 1 out of 6603 chunks

After that, free space is again displayed correctly.


WiFi Not Working On Ubuntu 18.04 after April-May 2020 kernel update

Try also the next solution taken from here:
sudo apt install git build-essential dkms
git clone -b extended https://github.com/lwfinger/rtw88.git
sudo dkms add ./rtw88
sudo dkms install rtw88/0.6
sudo modprobe -r rtl8723de && sudo modprobe rtl8723de

And Wifi works after reboot without doing any configuration, at least
in my case in Ubuntu 19.04.
If not, try command to write it into configuration file (replace 3 to 1, 2 or 4 if signal is weak).
echo "options rtl8723de ant_sel=3" | sudo tee /etc/modprobe.d/rtl8723de.conf


Unity and Dash displayed under all active windows

First you need to install myunity.
this is how:

open terminal

type in, sudo add-apt-repository ppa:myunity/ppa

type in, sudo apt-get update

type in, sudo apt-get install myunity

Then that is done, open up the dash and type myunity.

And it should come up as this,

Then click the arrow that is Behavior,

And click fixed. That is all, tell me if you have problems.


file -i vs file property accuracy, how to check if file is text file

man file says:

file tests each argument in an attempt to classify it.  There are
three sets of tests, performed in this order: filesystem tests,
magic tests, and language tests.  The first test that succeeds causes the file type to be printed.

You could try these options:
 -k, --keep-going
         Don't stop at the first match, keep going.  Subsequent matches will be have the string ‘\012- ’ prepended.  (If you want a
         newline, see the -r option.)  The magic pattern with the highest strength (see the -l option) comes first.

 -l, --list
         Shows a list of patterns and their strength sorted descending by magic(5) strength which is used for the matching (see also
         the -k option).


12.10 Movie Player crashed entire system

Use VLC forever. What's so special about that movie player that you don't even mention its name? There are thousands of movie players out there. Is it worth the troubles you're going through? maybe it's a buggy player.

Here's what to do when Linux freezes.


Installation was stuck after the partitioning screens have gone by, now no OS or any partitions on my hard drive

You can put ubuntu on a flash drive and then boot it from that flash drive without installing it to your hard drive and take any corrective actions using the os running from your flash drive.

To create a bootable flash drive using another windows pc, follow these instructions: http://www.ubuntu.com/download/desktop/create-a-usb-stick-on-windows

Then, next time you boot your latitude, you will have to tell your laptop to use the flash drive to boot. This will likely involve pressing a button as the computer boots (the splash screen will probably tell you which button).

Once you are running ubuntu from your flash drive, you can use a utility such as gparted to format your hard drive or take any other action


How come a daily build is behind snapshot releases like beta or RC?

Simple Answer:

The Firefox Release Candidate (RC) is a refined build. The nightlies continue to be minefields. I would disable the nightly ppa. Then, download the RC to /opt and symlink /opt/firefox/firefox to /usr/local/bin/firefox. Once there is an official ppa for the RC releases maybe install that, but the RC from Mozilla should auto-update.

RC vs Nightlies/Dailies:

I deduce, since their launchpad has nothing to say for itself, that the Ubuntu Mozilla Daily team pulls source from Firefox and builds it. That source code is the same foundation for Mozilla.org's Nightly Builds, which you can see is currently labeled by Mozilla.org: firefox-4.0b13pre. (Possibly I'm wrong, and the Ubuntu Daily Firefox team actually pulls source from mercurial that has passed basic tests. Regardless, it's in the same category as Mozilla.org's nightlies).

The Mozilla.org Firefox Release Candidate (RC) 1 is a nightly build tested, spit-polished, and renamed. It is not an official 4.0 release, which is why you don't see the nightly builds move from 4.0b13 to 4.01 or whathaveyou. The RC has its own source branch (which I'm sure you can get using mercurial), but really won't be hacked on. You can also find the static source for RC1 at the public ftp site.

The next RC will not be built off of the RC1 code branch. It will be another nightly build tested, spit-polished, and renamed Mozilla Firefox RC2.

More about nightly builds:

Mozilla.org has this to say about its nightly builds (thus also the launchpad-mozilla-daily's daily firefox builds):

  We make nightly builds for testing
  only. We write code and post the
  results right away so people like you
  can join our testing process and
  report bugs. You will find bugs, and
  lots of them. Mozilla might crash on
  startup. It might delete all your
  files and cause your computer to burst
  into flames. Don't bother downloading
  nightly builds if you're unwilling to
  put up with problems.

You'll note that Ubuntu-Mozilla-Daily's last attempt to build Firefox failed.

That said, the nightly builds should be fairly close to the release candidates, for reasons that should now be obvious.


Setting Passwordless ssh when a home directory is shared with NFS

Did you generate the key in master or slave?
Try this on both master and slave:

chmod go-w $HOME $HOME/.ssh
sudo chmod 600 $HOME/.ssh/authorized_keys
sudo chown 'username' $HOME/.ssh/authorized_keys

"username" is the name of the user you need to enable ssh.

Try this if the above method fails:

ssh-copy-id -i ~/.ssh/id_rsa.pub USERNAME@HOSTNAME.local

Enter this command from slave.


Older system, latest version of flash player doesn't work

I had a similar issue, installing an older flash fixed it.

Download and install Adobe Flash player plugin v10.3.x.x, download the latest version on the 10.3.x.x series. At the time I installed, it was v10.3.183.43, and I will use that one for the examples.

The file is huge (61 MB), and contains a lot of stuff, but we will extract it, and then extract another .tar.gz file that is the one that contains the libflashplayer.so file we are going to install.

Just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command(s) below:

unzip fp_10.3.183.43_archive.zip && cd fp_10.3.r183.43_archive/10_3_r183_43/
tar -xvzf flashplayer_10_3r183_43_linux.tar.gz && cd flashplayer_10_3r183_43_linux
sudo mkdir -p /opt/flashplugin-nonfree/v10.3.183.43
sudo cp libflashplayer.so /opt/flashplugin-nonfree/v10.3.183.43/

Now that you have the file for Flash player v10.3.183.43 in place, we use update-alternatives to install it as an alternative of a Flash player

sudo update-alternatives --install /usr/lib/mozilla/plugins/flash-mozilla.so  flash-mozilla.so /opt/flashplugin-nonfree/v10.3.183.43/libflashplayer.so 10

Then, just in case you have another version of Flash installed (for example, the broken one that gets installed with the flashplugin-nonfree package), run this:

sudo update-alternatives --config flash-mozilla.so

This will prompt you to select a choice for the alternative flash-mozilla.so.
Just select the one we just installed. Don't worry at all about the auto/manual stuff regarding alternatives, just ignore that.


Best practice is to only use root when you need it. By using sudo su, you are indeed giving the devil access to the kingdom. It was annoying to me at first, but remembering to use sudo in front of a command has saved me from making massive mistakes. I have had an experience where using sudo su has ruined everything, in a work environment.

Story time

We were using a CentOS server to run an application. The server was old, and had been turned into a VM, because its hardware was dead/dying. We had a raid corruption occur and the VM was damaged. Our backups were damaged too, so the only hope to recover data was mount VM and try to pull it all. I used sudo su and got to work. I recovered about 10% when I accidentally ran the wrong command, it wiped the database and we lost the application and all data. I have never run sudo su again, and I won't. Lesson learned the hard way.


is there a conky companion that allows me to read rss feed?

conky indeed is used for system monitoring such as CPU, HDD, system messages , etc... So I don't think you could find a rss reader.

Instead you can use a similar approach called screenlets.

  creenlets are small owner-drawn applications (written in Python) that
  can be described as "the virtual representation of things
  lying/standing around on your desk". Sticky notes, clocks, rulers, ...
  the possibilities are endless.

You can find multiple kings and types from http://gnome-look.org/?xcontentmode=6700.

Now back to what you want. First add the screenlets repository:

sudo add-apt-repository ppa:screenlets/ppa

sudo apt-get update

Now you can install a rss reader called feedreader-screenlet

sudo apt-get install feedreader-screenlet


Command for checking the default terminal

x-terminal-emulator is rigged up as part of the alternatives system to call an available terminal.

Note that this is system-wide and not a desktop-specific thing so it could mean that Gnome Terminal runs on KDE if both it and Konsole are installed... But it's close enough IMO.

I've also found that there's a $COLORTERM environment variable defined. On this Kubuntu machine —without gnome-terminal installed— it's still set to Gnome Terminal. So perhaps not that reliable.


If you really need Java 6 try to build libnsl from source. Guide here. I simply would recommend to install Java 8 and compile with javac -source 1.6 -target 1.6. Look at this question for more info how to compile for older versions of Java. (Don't use Java 9 or newer as not all programs from java 8 and older will run there.)


I found my mistake.
The problem was in MS Word, I saved all commands in a doc file and just copy and paste them. MS Word does regular - in longer – in some cases. So, this longer dash break my last command:

ssh -L 33061:localhost:3306 tunneluser@1.1.1.1 -f -N


Maybe you are actually logging in but you cannot see the panel bar and the launcher bar. If this is the case, try the following:

Hit the Super key (Windows key), wait for a second, type "Software Sources", wait for a few seconds, then hit enter.
The Software Sources app should pop-up in the middle of your screen, so you should be able to see it. Click on the "Additional drivers" tab.
Follow the displayed instructions to install the best driver for your hardware.


error: filename expected press any key to continue

The Linux Lite team made a modification to GRUB2 that causes this problem on  multi-boot machines when another distro is installed after Linux Lite. The solution is to use the Linux Lite GRUB2 boot loader instead of the Ubuntu (or other distro) boot loader.
The steps for doing this are described by gold-finger in his response to this post: https://www.linuxliteos.com/forums/suggestions-and-feedback/grub-quirk/msg2431.
Cheers!


How do I pin a particular MySQL version to avoid unnecessary upgrades?

If you want to prevent the upgrade of a package, then pinning is not the way to go. What you need is called holding, and you can find out how to do it on this page in the Ubuntu online help


How to setup multiple ipv6 addresses with dyndns in xubuntu?

I would set up my adresses in /etc/network/interfaces as an auto IPv6 device and then just add some up and down settings.  THat is because they are kind of static and the machine isn't likely to change IPv6 addresses.

I would add this to /e/n/interfaces:

auto eth0
iface eth0 inet6 auto
    up ip -6 addr add 2001:470:**:**::*0/64 dev eth0
    up ip -6 addr add 2001:470:**:**::*1/64 dev eth0
    up ip -6 addr add 2001:470:**:**::*2/64 dev eth0
    up ip -6 addr add 2001:470:**:**::*3/64 dev eth0
    up ip -6 addr add 2001:470:**:**::*4/64 dev eth0
    post-up curl "http://dyn.dns.he.net/nic/update?hostname=a.***my-domain***.ru&password=***&myip=2001:470:**:***::*0" || true
    post-up curl "http://dyn.dns.he.net/nic/update?hostname=b.***my-domain***.ru&password=***&myip=2001:470:**:***::*1" || true
    post-up curl "http://dyn.dns.he.net/nic/update?hostname=c.***my-domain***.ru&password=***&myip=2001:470:**:***::*3" || true
    post-up curl "http://dyn.dns.he.net/nic/update?hostname=d.***my-domain***.ru&password=***&myip=2001:470:**:***::*2" || true
    post-up curl "http://dyn.dns.he.net/nic/update?hostname=e.***my-domain***.ru&password=***&myip=2001:470:**:***::*4" || true
    down ip -6 addr del 2001:470:**:**::*4/64 dev eth0
    down ip -6 addr del 2001:470:**:**::*3/64 dev eth0
    down ip -6 addr del 2001:470:**:**::*2/64 dev eth0
    down ip -6 addr del 2001:470:**:**::*1/64 dev eth0
    down ip -6 addr del 2001:470:**:**::*0/64 dev eth0
# eof

See manual page for man 5 interfaces for more information.

I would also replace the IPv4 address 127.0.1.1 to my real IPv4 address on eth0.  And I would copy that line and replace 127.0.1.1 address with my static IPv6 address.  I might also add names for the other IPv6 addresses, which would be useful in configuration files.


Custom install works in one VirtualBox, not others or on hardware

Due to my human error, only the last of these lines was getting run:

apt-ftparchive -c $APTCONF generate $BASEDIR/apt-ftparchive-deb.conf
apt-ftparchive -c $APTCONF generate $BASEDIR/apt-ftparchive-udeb.conf
apt-ftparchive -c $APTCONF generate $BASEDIR/apt-ftparchive-extras.conf

Running the other two fixed the problem. The conf files were as in https://help.ubuntu.com/community/InstallCDCustomization, with 'xenial' changed to 'bionic'. As described in that web page, I also had to put the override files in /opt/indices, with:

pushd /opt/indices
for SUFFIX in extra.main main main.debian-installer restricted restricted.debian-installer; do
  wget http://archive.ubuntu.com/ubuntu/indices/override.bionic.$SUFFIX
done


Issues with installing Splashtop Streamer, (Beta)

There is a working solution here.

From the above link, as stated by Northreigh:

Download : libavutil51_0.8.10-1_amd64.deb

Install the downloaded deb file:

sudo dpkg -i ~/Downloads/lib*

Now , installing splashtop via Software Center should work.

Start splashtop via command-line as launcher icon failed to work:

python /opt/splashtop-streamer/SRStreamer.pyc


After searching, I have found a simple answer. Just execute

killall pulseaudio

Your speakers should work fine now. To ensure this, test the sound stack in System Settings > Sound > Test Sound (Speaker test, Not Digital Output (S/PDIF) test)


How to prevent Audacious to control overall system sound?

Change the output plug-in. Go to File  - Preferences - Audio:

(In my case changing from Alsa Output to PulseAudio Output solved the problem)


Are there keybboard drivers for a compaq kb-9963 keyboard?

If you you're still looking for a Windows 7 driver, you can find it here

Don't worry,  the driver is also in english ;)


Print again the last printed paper using command line

Open your cups webinterface localhost:631 and check this:

Note this:

1d = Maximum age of a job
500 = Maximum number of saved jobs

depending on what occurs at first

Now you can restart the latest job with this command in a terminal:

lpstat -W completed | head -n1 | awk '{print $1}' | xargs -I {} lp -i {} -H restart

shorter

lpstat -W completed | head -n1 | awk '{system ("lp -i "$1" -H restart"}'

compact

lpstat -W completed | awk 'NR>1{exit};{system ("lp -i "$1" -H restart")}'