Can you delete the Humanity icon theme safely?

Well, first switch to an icon theme other than Humanity?

System-Preferences->Appearence->Customize->Icons

And then maybe remove the package instead of just deleting them:

sudo apt-get remove humanity-icon-theme

Oh, I'm sorry I didn't read all you wrote. This does remove at least
gnome-themes-ubuntu, humanity-icon-theme, light-themes, software-center,
ubuntu-artwork, ubuntu-desktop, and ubuntu-mono.

Chris


Wireless card doesn't work for an HP DV2104

I had this problem with a HP DV5000 series laptop, so it may not be the same as yours, but maybe you can use some of the steps to get you in the right place.

1st you need to identify your driver, and they way I do that is get a list of my hardware on my computer.  Open terminal and see if the program that you need is installed.  More than likely it is.sudo apt-get install lshw  lshw is a Hardware Lister.  If and when the program is loaded, now you can send a copy of your hardware to your home folder and you can save it in you Ubuntu One or Dropbox folder to keep as long as you have your laptop.  Now in terminal type sudo lshw -html > your-file-name.html and if you want you can change where it says your-file-name to whatever you want.  When the program is complete just go to your home folder and open the html file created.  It should open with Firefox, Chromium, Chrome... When it is open, scroll down to where your wireless lan controller, it should look like this.

Under configuration on my laptop it says its a b43 driver.  Now I downloaded the older Synaptic Package Manager in the USC (Ubuntu Software Center).  After downloading I opened the Synaptic Package Manager a did a search on B43 and this is what I got;

Notice what choices I made and the choices I did not make.  If we are lucky and the drivers are same, all should work.  If you have a different driver then search what your driver is.  With a little good luck it should work.


How to switch from Mir to Surfaceflinger?

Connect your Nexus to your Ubuntu desktop machine, check if it is connected with

adb devices

(a line "[device ID] device" should be returned) and then issue the commands

adb root

(maybe it tells you that you're already 'root') and

adb shell rm -f /home/phablet/.display-mir && adb reboot

I just did it successfully. Of course, the fallback to Android's surfaceflinger is not a fix but it's a temporary workaround.

Alternatively, run

adb shell
su
rm -f /home/phablet/.display-mir && reboot


What are the changes between kernel in 10.04 and 10.10?

Ubuntu 10.04 used Kernel version 2.6.32 with the DRM from 2.6.33[src]. Ubuntu 10.10 used 2.6.35.

The change logs are at  http://www.kernel.org/pub/linux/kernel/v2.6/, but they are big. The changes in .35 are in this 6.3MB text file. You may be better off searching Bugs in Ubuntu to find more about your particular problem. There are 34 results for "Inspiron 1501".


otrs gives an "Sub-process /usr/bin/dpkg returned an error code (1)"

This is a problem with the Ubuntu package. While the OTRS debian package is pretty well maintained, the Ubuntu package (which is derived from the Debian package) is broken and no-one really seems to care about it. See all bug reports here:

https://bugs.launchpad.net/ubuntu/+source/otrs2

So if you want to install OTRS from a package manager, choose Debian, or if you want to install OTRS on Ubuntu, please look at this procedure:

http://wiki.otterhub.org/index.php?title=Installation_on_Ubuntu_Lucid_Lynx_(10.4)

(yeah I know it is written for Ubuntu 10.04 and OTRS 3.0.x but the procedure is really very much the same)


Why cron tasks created by WWW-DATA are not running?

Cron will run the www.data items.  You can verify this with this simple test:

$ sudo crontab -u www-data -e

Add this entry:

* * * * * date >> /tmp/date.out

Now examine the output with:

$ tail -f /tmp/date.out

After you have done that to ensure your crontab is working you can work the actual scripts you want to run.

the user www-data while not have the same path as you, so lots of commands that work from your account will not work from the www-data user unless you specifically set the path for that script.  www-data's default path contains only: PATH=/usr/bin:/bin

You can do this by exporting your path list, then placing it in a path list for the script.

You can do this with:

$ echo $PATH > ~/mypath.txt

Now append the text of the ~/mypath.txt to the top of your script as:

Your script:

#!/bin/bash

export PATH=$PATH:/home/users/l/j/ljames/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin
# rest of your script code here.

You can fine tune the path by removing some obvious items that you won't be using such as in the case of my example:

/home/users/l/j/ljames/bin
/usr/games
/usr/local/games
/snap/bin

That would leave the path line with of the script with:

#!/bin/bash

export PATH=$PATH:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin

# ... rest of your script code here

PHP script run in cron

The php test script (/home/users/l/j/ljames/test.php)

#!/usr/bin/php

<?php
        $string=`date`;
        print "Output from PHP script: $string";
?>

The php crontab entry

* * * * * php /home/users/l/j/ljames/test.php >> /tmp/date.out

You can examine the output with:

$ tail -f /tmp/date.out
Output from PHP script: Fri Feb  3 14:46:01 EST 2017

Output from PHP script: Fri Feb  3 14:47:01 EST 2017

Output from PHP script: Fri Feb  3 14:48:01 EST 2017

The output verifies that crontab will run your php scripts.  It shows that the culprit is the actual script, which would have to be debugged to function properly outside of cron first.  The likely culprit would the path list of the environment.

Note:
Your sytsem with your web server scripts run as user www-data will be more secure than if they were run-as you or root.  If they were as you, the script would have access to every thing that you have access to and if your web server were compromised it might even have root access with sudo.  Having your web server scripts run-as www-data, a compromised server will only be able to access your server.  Which, if backed up, would be easier to fix than to have to deal with your whole server.


I found out, what went wrong.

During an apt-get update on the Xubuntu 16.04 with the Kernel 4.4.0-21, it has been updated to a higher version (4.4.0-47). With this update somehow, the user "user" had lost the ability to start the xubuntu-desktop.

--> By the way: Writing in /etc/init/lightdm.conf (as written in my question) had no effect. Reason: This works only on an older version of Xubuntu, ... https://wiki.ubuntuusers.de/LightDM/ ...
Strange is, the old conf-file still was available ...

What I've done: I added a new user. When I enter this name in a new lightdm-conf file (named by me as 90-autologin.conf) at the autologin (just for check reasons), everything works fine now.
Directory: /etc/lightdm/lightdm.conf.d/90-autologin.conf

--> --> Additional question:

With the new user account all the old links from the broken user account are gone, so on the new account only the xubuntu-desktop runs now.

How can I repair the old user account "user"? All programs are linked to this account ... Is there a way to copy/paste those links ?

Thank you for your help in advance!

Regards Highway.


Based on this article:
https://support.symantec.com/en_US/article.TECH101598.html

They support Ubuntu 12.04

Also here:

http://www.symantec.com/endpoint-protection/system-requirements/
...they mention symantec endpoint protection 12.1.6, and Ubuntu is listed in supported OS (but version is not specified)

@mark kirby: There is even a tutorial on their website, says it works for Ubuntu

http://www.symantec.com/connect/articles/how-install-symantec-endpoint-protection-1215-ru5-linux-operating-system

Also as @JoKeR pointed out, there is site with supported kernels:

https://support.symantec.com/en_US/article.TECH223240.html


This means grub is fine, but it can't find the configuration. The following links should help you out. It takes some reading but explains how to go from here.

https://www.linux.com/learn/how-rescue-non-booting-grub-2-linux

https://help.ubuntu.com/community/Grub2/Troubleshooting

Good luck!


Ubuntu touch os in Micromax A110 Canvas 2

There probably isn't a way to simply install Ubuntu on this device, unless you are planning to port the code yourself.

The site you linked includes a list of devices which have a working port, here:-  https://wiki.ubuntu.com/Touch/Devices


How do I get an Intel CS630 webcam working?

Thanks to various Ubuntu & Linux community, I was able to get my Intel CS630 Webcam to run with Skype and Cheese (Ubuntu 12.04 32bit) using the following commands:

sudo rmmod gspca_spca500;
sudo rmmod gspca_main;
sudo modprobe gspca_spca500;

sudo modprobe -r gspca_sunplus;
sudo modprobe gspca_sunplus;

LD_PRELOAD=/usr/lib/i386-linux-gnu/libv4l/v4l2convert.so skype


Partition is misaligned by 3072 bytes... Pavilion DV7-6199US

The older hard drives used smaller 512-byte sectors; recently newer drives use larger sectors, usually 4096 bytes.

Software, however, is still sees the disk in 512-byte "logical" sectors, although it often reads the data in 4K chunks

When creating a partition, it is important to align the beginning of the partition with the beginning of the large physical sector, otherwise each read will require reading 2 physical sectors, which will affect performance.

As you can see, your partition starts from logical sector #3 (#1 and #2 take 512*2=1024 bytes), so to fix the problem you need to move the start of the partition by 3072 (4096-1024) bytes.

Newer versions of gparted are aware of this - just boot from Ubuntu LiveCD and create a new partition selecting the default alignment option (which is "align to 1 MB", which is optimal even for larger sector size, such as in SSDs).

If you already installed OS and do not want to re-create partitions, you could move the start of the partitions to align properly, but that would involve some pen-and-paper calculations. Also, you'll need to reinstall the bootloader if you moved Ubuntu partition.


HPLIP 3.12.4 plugin installer failing to install in LUBUNTU

I found a forum thread with this exact same error over at the Arch forums, but I can't help but wonder, if the only reason this plugin refuses to run is because of a GTK theme warning, couldn't you just run it from a non-GUI prompt? That is, press ctrl+alt+F1, login and then run it. Could be worth a shot.


how to add a “.so” library in a Netbeans project in Ubuntu

install the librxtx-java through the terminal:

sudo apt-get install librxtx-java

this should be sufficient, I think - I'm no java-developer, though.


Disable all visual effects in Ubuntu 15.10

There are some you can disable using the unity-tweak-tool.

Install:

sudo apt-get update
sudo apt-get install unity-tweak-tool

Run:

unity-tweak-tool &

Click on Launcher (in the Unity section) and in the Launcher tab:

set Auto-hide to off
set Urgent animation to No animation
set Launch animation to No animation
set Icon backgrounds to No colouring.

In the Search tab:

set Background blur to off.

Click on the Overview button at the top to go back to the main menu.

Click on General (in the Window Manager section).  In the General tab:

set Desktop magnification to off
set Texture quality to Fast
set Window Animations to off.

Additionally, you can turn off more animations in ccsm.

Install:

sudo apt-get install compizconfig-settings-manager

Run:

ccsm &

In the effects category, untick all of the boxes.

In the accessibility tab, untick all of the boxes.

There are probably more you could disable in compiz as well.


For scheduling regular tasks crontab is a general solution. In your case the logout session should be the trigger. Here lightdm seems best I would say.
You can make a bash script stating your commandline sync and insert it into the /etc/lightdm/lightdm.conf file by:

  session-cleanup-script=/path/to/script

For further details another answer already exists on:

Execute a script upon logout/reboot/shutdown in Ubuntu

In case you wish to sync also at regular time intervals you can also use crontab in parallel to run your bash script. Here you need to be aware that contab also runs when you are logged out which is not needed.
here you could check the username (your name) if logged in before starting the grep command:

  if whoami | grep -q {yourname}; then {your grep command} ;  fi;


Create a small shell script like this one:

#!/bin/bash
openssl pkcs7 -inform DER -in "$1" -print_certs -out "$1.pem"
openssl smime -verify -in "$1" -inform der -noverify -signer "$1.pem" -out "$1.pdf" 2>/dev/null
rm "$1.pem"
evince "$1.pdf"
rm "$1.pdf

Make it executable
Select "open with other application"
Choose the small script created above
Done.


Was due to a very trivial reason. I clicked on the Maximize button of my browser and observed that it hung up (stopped responding) and the processor usage shot up. Also the terminal from which I had started my browser showed a handful of "Gdk-CRITICAL **: IA__gdk_window_get_origin: assertion `GDK_IS_WINDOW (window)' failed" errors. I remember reading that this is a theme issue. I started emacs and maximized its window and it too worked flawlessly. Same with almost all applications - they hang up on reduced window size but work fine in maximized form. Also changing the theme (Any except radiance / ambiance) fixes this issue and I could use applications in maximized or reduced size.

On a side note, is the theme issue persistent or has been fixed?


FIXED: No grub bootloader - previously working

It's not 100% clear to me what you did; however....

Under EFI, information on boot loaders is stored in NVRAM. This information includes both pointers to the disks, partitions, and filenames that hold them and the order in which the firmware attempts to launch them.
Many (but not all) EFI-based computers "helpfully" delete invalid boot loader entries from NVRAM. Thus, if you unplug a disk and power on the computer, its boot entries may disappear. This may be at least part of what happened to you.
All EFIs support a fallback boot loader filename of EFI/BOOT/bootx64.efi (on x86-64/X64/AMD64 computers), which is launched if the NVRAM-based entries all fail to boot. Many OSes, including Windows, put a copy of their boot loader in this location. This feature, and the next, can mask problems caused by the former feature, especially on Windows-only computers; but in a dual-boot scenario, the boot loader you want to control the boot process must be in the fallback position for this feature to do what you want.
Some EFIs include the Windows boot loader (EFI/Microsoft/Boot/bootmgfw.efi) as a sort of secondary fallback boot loader, which is launched if the regular fallback boot loader doesn't work (or is tried before the regular fallback boot loader).
Depending on how you do it, cloning a disk might or might not make the cloned disk bootable if you swap it out from the original disk. The boot loader reference in NVRAM might not match the reference on the new disk because it might not have been copied, because the partition number is different, or because the partition's GUID may be different.
Sometimes the NVRAM-based boot variables can become damaged, or attempts to add new entries can fail. This can result in a fresh OS installation being unbootable, even if a previous installation worked. Sometimes using the firmware setup utility's option to reset all variables to their default can fix the problem, but that won't make new entries magically appear; you must still create a new entry.
New NVRAM entries can be created in Ubuntu with efibootmgr, in Windows with bcdedit or EasyUEFI, in an EFI shell with bcfg, or in other ways.
Controlling the boot mode is critical. The prompt you got in Boot Repair to create a BIOS Boot Partition indicates that you booted in BIOS/CSM/legacy mode, from which it's impossible to modify the EFI-mode NVRAM boot variables. You must boot in EFI/UEFI mode to modify these variables. See this page of mine for information on controlling your boot mode.

It sounds like some combination of these factors has led your new disk to be unbootable. Depending on the details, you can probably fix it with efibootmgr from an EFI-mode boot of a Linux emergency disk. A command like this should work:

sudo efibootmgr -c -d /dev/sda -p 1 -l \\EFI\\ubuntu\\shimx64.efi -L ubuntu

This command creates a new ubuntu boot entry for EFI/ubuntu/shimx64.efi on /dev/sda1. You must change the options as necessary for your system. Note also the use of doubled-up backslashes (\\) as directory separators to the -l option, but forward slashes (/) for the device specifier passed to the -d option.

The Boot Repair tool will do this, plus install or re-install GRUB; however, as noted above, it appears you booted your repair disk in BIOS mode, not in EFI mode.

Another option is to use my rEFInd boot manager on USB flash drive or CD-R. It boots only in EFI mode, so if you can boot rEFInd, and if it successfully boots Ubuntu, you'll be in EFI mode. You can then use efibootmgr, run Boot Repair, or install the rEFInd PPA or Debian package to restore your system to bootability.

All of this assumes that your only problem is a missing or damaged boot loader. If your OS needs re-installation, that's another matter entirely.

For more information on EFI-mode booting, please read one or more of the following:

Adam Williamson's blog entry on how EFI works -- This page describes the theory behind EFI-mode booting.
A question and answers on the differences between BIOS and EFI booting on Superuser.com -- This provides the basics of the preceding, but is more concise.
My page on installing Linux on EFI systems -- This page is a more practical introduction to EFI-mode booting than Adam Williamson's blog.
My page on EFI boot loaders for Linux -- This page describes EFI boot loader choices for Linux systems.
My page on the CSM -- This page covers the CSM, including when it's useful and when it's not.
The Ubuntu community wiki entry on UEFI -- This page is a bit disjointed, but is the most Ubuntu-specific introduction to EFI and its issues.


Remove the offending package:

sudo dpkg --remove fspc libwxgtk2.8-0:i386
sudo apt-get -f install

Now install it like pro's do, using gdebi:

sudo apt-get install gdebi-core
sudo gdebi /path/to/fscp.deb


Ubuntu 20.04 doesn't come back from hibernation, but restarts

The line in /etc/default/grub is wrong.

It should be resume=UUID=<swap UUID> or resume=/dev/sdc2.


Strange, it works exactly that way over here.

First, try to find out what the file is:

file xfile

The file command looks inside the file and based on certain "magic" tries to figure out what that program does.

From what you describe I guess that it is a shell executable that tries to execute yet another program. If this is the case, why don't you post the code of the shell executable using http://paste.ubuntu.com.


Load images by default for HTML Emails in Evolution

In Evolution, open Edit > Preferences > Mail Preferences > HTML Messages. You should see an option for "Loading Images." Select "Always load images from internet."


Can't access to hard drive to create partition in Gparted

There might be multiple (some incorrect) file system signatures on disk device sdb.  This can happen if an ISO image was copied to the drive in the past, but was not completely removed before the drive was partitioned.

To learn more run the following two commands:

sudo blkid /dev/sdb

sudo wipefs --no-act /dev/sdb

If the drive is supposed to be partitioned as shown by the fdisk command, and if an ISO signature is discovered but not supposed to be there then you can use the wipefs command with the appropriate options to remove just the ISO signature.

NOTE:  To avoid loss of important data, be sure to have a backup of your data before editing partitions and wiping out file system signatures.


Error message; [IP]in-addr.arpa has no PTR record:

I would use nmap to do ping scanning (as root) e.g.

sudo nmap -sP 192.168.1.*

If nmap is not installed, just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command(s) below:

sudo apt-get install nmap


How to recursively list only hidden files from a terminal

To recursively list only hidden files from a terminal, you can use the tool find with the -type f option:
find ~ -type f -name '.*'

This will find all files in the user's home directory for which the basename starts with a dot, i.e., a hidden file or folder. Remove -type f to list both hidden files and folders, or specify type d to list only hidden directories. Specify any other directory by replacing ~ with a valid pathname. Specify . to list hidden files in the current working directory and below.


New to UBUNTU, need a learning experience

You don't have to install it on your machine in order to try it. There's what are called "Live CDs" or "Live USBs" that you can boot from, run Ubuntu wihtout any modification to your existing system (unless, of course, you actively erase or modify your files), and when you reboot again the original OS comes back unmodified.

You can check this guide on the official ubuntu site on how to try ubuntu befor you install it.


You can find a summary of the differences introduced in each new kernel here.

In general, newer kernel versions add more features and fix bugs, but the differences for the end user between minor versions are unlikely to be noticeable, unless support was added for a specific piece of hardware you use.

A new minor version of the kernel is released every 2-3 months, and given the wide variety of hardware supported the majority of changes made to each version probably do not affect your specific configuration.

In common with other distributions, the kernel shipped with Ubuntu is slightly modified from the "mainline" version, see https://wiki.ubuntu.com/Kernel/FAQ/UbuntuDelta if you're interested in the gory details.

Note that Ubuntu 12.10 Quantal uses kernel version 3.5.0.


error: Could not load host key: /etc/ssh/ssh_host_ecdsa_key

The commented lines in sshd_config are the default values (in other words the behavior doesn't change if you uncomment them). So your sshd is actually looking for the ECDSA and Ed25519 keys (RSA is now considered "weak" and no longer the default encryption).

AFAIK these keys are automatically generated when you install the SSH server but you can (re-)create them with:

ssh-keygen -f /etc/ssh/ssh_host_ed25519_key -N '' -t ed25519
ssh-keygen -f /etc/ssh/ssh_host_ecdsa_key -N '' -t ecdsa


How to scroll through pages in previewed pdf's on Dolphin file manager?

Thats no "real" preview of the file, but just a thumbnail created for it.
So scrolling is not possible.

Unfortunately there seems to be no real KDE/Plasma/Dolphin-alternative to gnomes sushi or gloobus, both of which work with Nautilus. In Plasma 4 there used to be klook, but it never got ported to plasma 5 afaik.


Installing Windows 7, UBuntu 12.04 and Fedora 18 (19) in triple boot with SWAP and Files space in HDD

the 400gb partition you want use, format it as ntfs only and add mount entries of that partition in /etc/fstab of both ubuntu and fedora . assuming 400gb partition no as 5
/dev/sda5   /home/username/pictures   ntfs   defaults  0 0 (you can change mountpt as you want)

swap should be twice of ram if ram is less than 4gb if greater than 4gb then swap space 4gb is enough


Install Windows 7 on SSD while retaining Ubuntu dual boot on HDD

It's pretty much the same as your previous configuration. The easy way to do this is to install Windows to the blank SSD without the hard drive connected, then plug the hard drive back in, create your windows partition, then install Ubuntu, selecting to install on the free space of the hard drive.


Try this(not best way to solve this problem but it is working):

Download Ubuntu 11.04 and make LiveCD on pendrive or cd/dvd.

Boot LiveCD.

Use "upgrade Ubuntu" in options.


After update, get "error: file not found." followed by "grub rescue> _"

Use Boot Repair to fix your bootloader.

Boot Ubuntu from a LiveCD or Live USB
Connect to the internet
Open a terminal, and add the Boot Repair PPA

sudo add-apt-repository ppa:yannubuntu/boot-repair && sudo apt-get update
Install Boot Repair

sudo apt-get install -y boot-repair && boot-repair
Launch and use, see https://help.ubuntu.com/community/Boot-Repair#Using_Boot-Repair for more details


I run an Ubuntu Server myself, and various times I feel the need of a GUI. This has however proved itself to be a reflection of my own fright.

If you just take the time to learn one texteditor (such as nano), you will learn a lot more in the process. You can install mysql by using sudo apt-get install mysql-server, and then you edit the configuration to your needs.
What I usually do next is that I use some kind of graphical tool (such as Mysql Workbench) on my client PC to connect to the mysql server and create databases.
https://help.ubuntu.com/12.04/serverguide/mysql.html

If you however want a graphical interface on the server, you could use a webgui such as Webmin. This way, you probably save more resources than if you would install the ubuntu desktop, and when the graphical interface is not needed you can stop the service to release RAM if you are worried about resources.
http://www.webmin.com


The difference between simply installing software & adding to repository

There are three steps to what you're running:

add-apt-repository adds a PPA to your list of sources, so that Ubuntu knows to look for updates from that PPA as well as from the official Ubuntu sources. Usually this is used to allow developers to provide updates more quickly than those in the official Ubuntu repositories.
apt-get update tells apt-get to update its database of what packages can be installed and where to install them from. In this case, apt-get will see your newly-added PPA and discover that ppa:maco.m/ruby has the newest version of rubygems that it knows about, so it will make a note to install rubygems from the PPA next time someone asks to install it.
apt-get install causes apt-get to find the package in its database and download and install the indicated file. In this case, it will find the rubygems package, download it from ppa:maco.m/ruby, and install it.

If you were to simply run apt-get install rubygems, you would get a less-recent version (or perhaps nothing at all, depending on whether rubygems is also in the Ubuntu repositories or only in the PPA).

In general, the format ppa:a/b will expand to https://launchpad.net/~a/+archive/b, where you can view the files and download them individually. In your case, that would be https://launchpad.net/~maco.m/+archive/ruby.


Well almost - once this bug is resolved then the top pesky nautilus menu-bar will disappear!

How to...

Some prerequisites - install gnome-session-fallback & avant-window-navigator.
Logout and login with the new session "gnome classic"
start awn-settings and configure awn as you need to - ensure you tick the box to start awn automatically.
Run gnome-session-properties and add a new item compiz --replace
Edit /usr/share/gnome-session/sessions/gnome-classic.session and remove "gnome-panel"
Edit /usr/share/gnome-session/sessions/gnome-fallback.session and remove "gnome-panel"
Logout and login


Terminal method
sudo apt-mark hold <package-name>

The same command also works for multiple package names.
Explanation:
hold
    hold is used to mark a package as held back, which will prevent the
    package from being automatically installed, upgraded or removed.
GUI method
If you have a specific package that you don't want to update, you can lock the package to a specific version using the Lock Version feature of Synaptic. Install Synaptic from the Ubuntu Software Center.

Open Synaptic and search for the package whose version you want to lock.
Select the package whose version you want to lock in the center pane of Synaptic.
From the Synaptic menu select Package -> Lock Version. A small lock emblem will appear in the green checkbox to the left of the package name to show that the package version is now locked.
Click Package -> Lock Version again to unlock the package version.


Can't boot from linux USB boot disk after installing 18.04

So it looks like my hardware just isn't keen on 16.04... reinstalling 18.04 works shrug


Batch convert H.265 mkv to H.264 with ffmpeg to make files compatible for re-encoding

Yes, using ffmpeg.

Open a terminal and direct it to the directory containing the H.265 encoded files, assuming you have ffmpeg and the appropriate libraries installed and assuming they are in MKV format copy and paste the following into the terminal window.

INPUT="$1"
for i in *.mkv ; do
    ffmpeg -i "$i" -bsf:v h264_mp4toannexb -sn -map 0:0 -map 0:1 -vcodec libx264 "$i.ts"
    mv "$i.ts" "$i.mpg"
    sleep 3
done

There you have it. This will convert to h.264 in an MPG container in the same directory.

Explanation of the command switches:

for i in *.mkv ; do ... done

This sets up all .mkv files in a directory to be included in the batch process. This may be changed to accommodate the container extension of the files you wish to process.
ffmpeg -i "$i"
Executes the program ffmpeg and calls for files to be processed.

-bsf:v activates the video bit stream filter to be used.
h264_mp4toannexb - Is the bit stream filter that is activated.

Convert an H.264 bitstream from length prefixed mode to start code prefixed mode (as defined in the Annex B of the ITU-T H.264 specification).

This is required by some streaming formats, typically the MPEG-2 transport stream format (mpegts) processing MKV h.264 (currently)requires this, if is not included you will get an error in the terminal window instructing you to use it.
-sn stops the streaming of subtitle streams (for those that do not want subtitles in their video) This is optional and can be removed.
-map 0:0 -map 0:1 Tells ffmpeg to only process the first two streams of the file (0:0 is the video stream, 0:1 is the first audio stream of the file). This does two things, strips the excess audio streams, usually the first audio stream is English but not always. Other streams such as embedded subtitles are removed reducing the file size. This is also an optional string. You can use ffprobe to view the streams available in the file. -map is optional and can be discarded from the command.
-vcodec libx264
This tells ffmpeg to encode the output to H.264
"$i.ts"
Saves the output to .ts format, this is useful so as not to overwrite your source files.

mv "$i.ts" "$i.mpg" Converts the file extension to MPG in the same directory. This can be set up to send it to any directory you like.
sleep 3 - allows the process to rest giving ffmpeg time to queue the next file


Ubuntu does not recognize SSD during installation

It sounds like you have two drives configured in a bios fake raid.  If you must dual boot with windows, then your only hope is for the dmraid package to recognize the fakeraid under linux.  This should "work" though fakeraid does not actually handle failures correctly so if you are using it for anything other than raid0, you are in for a bad surprise when things to pear shaped since those levels imply redundancy and should tolerate failure.  If you are OK with that failure, then again, it should "work".  Run sudo dmraid -n and add its output to your question for more information.


Compizconfig needs rebind on every startup

This is just a workaround -

Set up compiz as you wish, then in ccsm go > Preferences > Plugin List

From there disable "Automatic plugin sorting" > in right side column (enabled plugins),  highlight scale & click on the Down button until it's below the unityshell plugin (usually the last listed

Then close ccsm leaving auto plugin sorting disabled. If making any changes in the future 1st re-enable auto plugin sorting, make changes then disable, ect.

2nd alt. workaround, don't do above one

Use a start up script to reset the binding. This could be done thru an autostart .desktop that is set for a small delay of a couple of sec.

One example of window picker all to bottom right

In ~/.config/autostart create a desktop file, named scale1.desktop here to test.

(- or create via cli -

mkdir -p ~/.config/autostart

gedit ~/.config/autostart/scale1.desktop

Insert, (copy & paste best way) this inside, the Exec= line has a command to set the binding, the delay line is set to 3 sec if need be it can be adjusted. Note that the command can also be run from a terminal to test, ect. Also note that the Exec= is one line if it appears differently in this post so do c&p rather than type, To show that,  the  command is

dconf write /org/compiz/profiles/unity/plugins/scale/initiate-all-edge "'BottomRight'"

So c&p this into the newly created .desktop file

[Desktop Entry]
Type=Application
Name=Set scale binding1
Exec=dconf write /org/compiz/profiles/unity/plugins/scale/initiate-all-edge "'BottomRight'"
Hidden=false
NoDisplay=false
X-GNOME-Autostart-enabled=true
X-GNOME-Autostart-Delay=3

Would look like this in gedit

A 3rd way would be to change the default bindings  of None for these actions  to what you want, however that's a bit involved & not suitable for here, ubuntu forums better for that.


I can not get my DVD's to work. Crashing VLC player

You need the library libdvdcss. Read this.

The package libdvdcss2 is not included in the official repositories, but can be easily installed.

Two short commands should help.

sudo apt-get install libdvdread4
sudo sh /usr/share/doc/libdvdread4/install-css.sh


Yes it's sort [file name]. That prints the sorted list to your terminal. If you want to redirect it to a file you can do sort [original file] > [sorted file]. If you have items starting with numbers, you can do sort -h insted of sort for a more intuitive sorting.


Intel HD4600 screen tearing on Ubuntu 17.04

Try adding i915.enable_rc6=0 to your boot parameter.  This should fix the tearing.  But it will disable an important power management module resulting in excessive fan use.


Will removed default apps come back after an upgrade to a new release?

No, the removed default application will not come back but the new default applications will be installed.

There are two cases:

When the default application is the same between upgrade it will not be installed e.g. Evolution between 10.10 and 11.04
When the default application has been changed e.g. 11.04 the default media player is changed from RhythmBox (10.10) to Banshee so even if you have removed RhythmBox, Banshee will still be installed.

The answer is based on my upgrade to 11.04 from 10.10


Okay, so my problem turned out to be that I had a corrupt Cookies file. I manually deleted the Cookies file in ~/.config/google-chrome/Default/ and that fixed the issue.

For ease of copy/paste, here are the commands:

cp ~/.config/google-chrome/Default/Cookies ~/.config/google-chrome/Default/Cookies.bak
rm ~/.config/google-chrome/Default/Cookies

As Yalok has said in comments below, if you have multiple profiles, you can do this:

rm -rf ~/.config/google-chrome/Profile*/Cookies


Ubuntu running very slow after install (16.04.3)

To be fair, this could be about a lot of things, but the main thing you're talking about is that everything's fine when running from USB, but not from hard drive. Is it possible that the HDD is failing? Did/does any other operating system working fine from the HDD? Or is it all slow?

I might as well throw in: did you do a clean install?

Thanks,
Jake


14.04 disk mount problem came our of left field

It seems like what you considered your /home partition never got automounted (at least it does not now). So Ubuntu still includes the /home directory to the root partition /. And of course, as it does not get mounted at boot time, you can  not manually unmount it either!

So I suppose we have to manually edit your /etc/fstab configuration file. Could you please post this by including it into your question? You can leave the first 6 lines out and start with the line beginning with "#
We might also need the output of sudo blkid /dev/sda7 to add this partition back to your automount list.

So when you attached those two pieces of information to your post, just leave me a short comment on this answer to wake me up... ;D
See you later!

CORRECTION: It is not the /home partition that fails but an independent NTFS backup volume! I misunderstood.


Why do I receive an error message while trying to access some of my GNOME shell extension settings?

I found a solution to this issue on this GitHub page. Basically, the problem is that some of the dependencies of the Clutter library are missing on Ubuntu (mine is 18.04 and the guy on GitHub is using 16.10). Just installing the following packages solves the problem:

sudo apt-get install gir1.2-clutter-1.0 gir1.2-clutter-gst-3.0 gir1.2-gtkclutter-1.0


Cannot connect to the Internet, wired or wireless

In the top-right corner of the screen, there should be several icons, similar to Windows' system tray in the lower-right corner or Mac's comparable section also in the top-right corner. One of these icons should be the network service. If it's using a wired connection, it will show an arrow going up next to an arrow going down. If it's using a wireless connection, it will show a fairly standard Wi-Fi icon that also indicates signal strength. If it's offline (or networking is disabled), it will show an outline of the standard Wi-Fi icon without any bars. If any of these icons show up, you can access additional settings by clicking on it. Perhaps your issue is as simple as enabling networking or changing a few of those settings.

But for the remainder of this answer, I will proceed with the assumption that you are having a similar problem to the one I encountered a few weeks ago, which made the network indicator disappear entirely. So if you can see one of these icons and clicking on it brings up some network-related options, you can just skip the rest of this and let me know what it looks like.

A few weeks ago, my work computer (running Ubuntu 14.04) randomly decided to be completely offline. It looked like the network manager service did not start at all, and starting it manually didn't help. If you're experiencing a similar-looking issue, I would start by trying to restart the network service. Run sudo service network-manager restart in the terminal. If that restores the network icon, then that may have fixed the issue. If, however, the icon is still missing, follow the instructions on this question's answer.

About this bug

Ubuntu uses, among other things, some libnl packages for certain networking functions, and there was a proposed update to these packages that had some compatibility issues with the network manager service. This should only affect people that have enabled proposed updates, although I don't believe I had enabled this setting, so I'm not sure how it affected me. Regardless, it apparently did, and following the instructions linked above fixed it for me. Note that you should also be sure you place a hold on the packages so they don't get updated until the bug is fixed either with a libnl update or a network manager service update (instructions at the link above).


Change the year of a file, keeping the month and day of month

You can use -t argument instead of --date. From man touch:

  -t STAMP
         use [[CC]YY]MMDDhhmm[.ss] instead of current time

Now, you can obtain that STAMP in the way you are interested using next command:

STAMP=$(stat -c %y f1219486.jpg | \
        awk 'BEGIN {FS="[-]|[:]|[ ]|[.]"} {printf $2$3$4$5"."$6}' | \
        sed -r 's/^/13/g')

Some explanations:

stat -c %y f1219486.jpg will return the time of last modification of f1219486.jpg
awk 'BEGIN {FS="[-]|[:]|[ ]|[.]"} {printf $2$3$4$5"."$6}' will change the output of the previous command in this format: MMDDhhmm.ss
sed -r 's/^/13/g' will add 13 (curent year) in front of MMDDhhmm.ss

And now you can change only the year of your file:

touch -t $STAMP f1219486.jpg


How to create a KDE start application menu launcher that launches the search and launch desktop?

I think i may have found the best possible alternative to my search. Its this new plasmoid called "Takeoff". It's not really the netbook interface but i must say I'm pretty pleased with its 1st release.


I'm not sure what you are asking, but some sites link to the
KELTRON Kerala State Electronics Development Corporation Limited (KSEDC).

It has Downloads page with link to the It@School Edubuntu 14.04.4 - 64 bit (the ISO is 3.5 Gb).


This could occur if the location containing the script (in this example, /var) has been mounted with the noexec option. You can confirm this by running mount. If so, modify /etc/fstab and re-mount appropriately.


Apart from waiting for the kernel to appear in the PPA (it's been released what, a day ago?), another option is to download a tarball and to compile it from sources.

Waiting for a PPA is safe, compiling from sources is fun. You choose :)


Where can I find the correspondent of "temp" folder in Firefox?

You can put about:cache in the location bar, it should display where it keeps the "temp" folder.


How can I change the function of the caps lock key within the Colemak keyboard layout?

You can force Caps Lock to be Esc on any layout:

In System ▸ Preferences ▸ Keyboard ▸ Layouts ▸ Options, set CapsLock key behavior to Make CapsLock an additional ESC.


external monitor stops the booting process - Ubuntu 16.04

It seems this has resolved my issue: https://help.ubuntu.com/community/NvidiaMultiMonitors

I can now boot with external monitor connected and change the resolution of the builtin screen by using the nvidia control panel.


Numpad behaves like arrow keys since upgrading to 13.10

You must have your numpad not locked. If you have the numlock button, just press it, if not you can use

  numlockx on

to install it : sudo apt-get install numlockx


Black screen after waking from suspend on Ubuntu 20.04

Seems like an amdgpu issue, which is resolved in kernel 5.8. As the current kernel is 5.4, you should do:
sudo apt install linux-generic-hwe-20.04-edge

I found the answer here: Is there a kernel 5.8 ppa for ubuntu 20.04?


broken apt-get - now can't install or meove anything

It seems that you installed a deb file that requires libraries that are incompatible with Ubuntu 14.04's libraries. You should simply uninstall what you installed.

sudo apt-get purge kompozer:i386


The menu.lst file was part of the original GRUB. Ubuntu now uses GRUB2 by default, so the config file has changed to /boot/grub.cfg.

Here is a rather long primer about GRUB2. Scroll down to section 5 to read about editing the GRUB config file. Note that you shouldn't edit this file directly in normal circumstances. Instead, editing /etc/default/grub is the preferred way to prevent overwriting your changes on update.

Here's another primer on editing the GRUB2 config file. It's not as technical.


Error while installing icecat Ubuntu 19.04

Maybe not installed?

sudo apt install pkg-config


Duplicity does not run via anacron in 14.04

doing

rm -rf ~/.cache/deja-dup/*
rm -rf ~/.cache/duplicity/*

seems to fix the problem.
Source https://bugs.launchpad.net/ubuntu/+source/duplicity/+bug/1318833


Changes to SD card undone after re-mount (e.g. deleted files re-appear)

At this point I would suggest running badblocks on the SD card to see what it finds.

It sounds like the card's write logic is damaged, what you see on a mount point is simply the cached version of your data. It's supposed to be written back via sync and during umount. Seeing that you don't mention that the SD card is hanging at all suggests the damage is severe enough to create false positive write back responses or in simpler terms your disk is lying to you when it says a write is complete.

You could try toggling the write protect switch while the card is removed from the system. e.g.

toggle write protect
insert
do something trivial
unmount/eject
reverse write protect
rinse/repeat

In an effort to tickle the circuitry which might be caching a "stuck at 1" value. Other than that, crush it so no one else suffers any more grief and toss it.


Can I connect totem/mplayer with my multimedia library as the default player?

Not sure there is an library for this, but you can edit the file /etc/gnome/defaults.list to change the gnome behavior of default application.


Vulnerability in Apache 2.4.12 Wiley 5.10

You should already have the most up-to-date version available through the official repositories.

However, you can use an external repository that provides newer releases. This Launchpad PPA has all the way up to 2.4.17 available for Wily (15.10).

You can add it via

sudo add-apt-repository ppa:ondrej/apache2
sudo apt-get update
sudo apt-get upgrade

If you still don't have the newer version of Apache2, try running sudo apt-get install dist-upgrade.

After all of these are run, you should have the updated (and thus patched) version of Apache2!


Is it possible to disable empathy from autostarting on login?

Look in /etc/xdg/autostart and the file telepathy-indicator.desktop
edit it and change NoDisplay=true to NoDisplay=false  and it will be shown in startup applications tool
if you want them all shown for you to disable/enable at will run this in terminal

find /etc/xdg/autostart/ -name "*.desktop" -exec sudo sed -i "s/NoDisplay=true/NoDisplay=false/g" '{}' \;


Append options to GRUB_CMDLINE_LINUX_DEFAULT without modification on files

Newer grub packages now provide to add files with own modifications at /etc/default/grub.d/ .
In my case I was able to modify grub with my packaging by:

thopiekar@t91:~$ cat /etc/default/grub.d/emgd.cfg
GRUB_CMDLINE_LINUX_DEFAULT="$GRUB_CMDLINE_LINUX_DEFAULT vmalloc=256MB selinux=0 vga=current"

Thank you all anyway :)


I guess you are trying to install the libjpeg8 package but you already have another (probably old?) version of libjpeg8 installed.

So you can either try removing the already installed version and re-install the newer one or make dpkg forcefully overwrite the confronting files by:

sudo dpkg -i --force-overwrite /var/cache/apt/archives/libjpeg8_8d-1+deb7u1_amd64.deb

Run sudo apt-get install -f to check everything is OK.


Reboot/shutdown causes BIOS not to find startup

I would check the output of efibootmgr command before rebooting.

The installation process might have configured the EFI boot options wrong so now the EFI firmware is unable the find the boot image. Or the system's boot images isn't located at a standard place in the EFI boot partition.

It's also possible to check and manually configure this with a live boot image.

If that's the issue, I'll be able to assist with more info.


Cannot change Empathy chat status from Me Menu when using IRC

This have happened to me too a few times. What I did was:

Make sure empathy is actually running (there should be a little arrow in the Messages indicator).

Open Empathy and check to see if it have failed to connect to a im network (msn, google talk etc.).

Usually it's the latter.


Is there any way to get Nautilus running again when it stops working WITHOUT rebooting?

I've worked it out.

I couldn't get nautilus to start yesterday afternoon. I slept on it, and left the computer running overnight (working on some BOINC tasks), and just came back to it now.

I tried to start nautilus, and as expected, the Unity Launcher icon flashed but the application didn't start.

This time, I started gnome-system-monitor to see if nautilus appeared in the list of current processes. It did. Hmm.

I right-clicked the nautilus process, selected "End", and then clicked "End Process". Then I clicked on the Unity Launcher nautilus icon, and the application started normally.

I hope this process is 100% repeatable, because it will save me a LOT of time.


I run 12.04 as a Free Cloud Desktop on AWS EC2 all constantly on the Free Tier Micro instance model. I have run Ubuntu Virtual Cloud Desktops on EC2 for years using The FreeNX software. NX Web Companion (for Browser enabled) and NX local client for machines where I can install the software instead of run the java piece. Also, added an RDP (Remote Desktop Protocol) for easier Windows access.

A little configuration work but easy once you understand it. It works well, though the web enablement is a little clunky. I am trying to find a better model on this post:

https://askubuntu.com/questions/258919/any-ideas-on-a-better-browser-enabled-cloud-desktop-using-ubuntu-12-04-gnome-an

Anyone can ping me if they want to see more about how it works. Here is how it is setup on AWS:

https://www.desktopanywhere.com/free_cloud_desktop/setup-your-desktop/setup-details/

Love AWS and Ubuntu


"No Wi-Fi Adapter Found" after upgrade from 18.04 to 19.10

I suggest that you try removing the backport package.

sudo apt purge backport-iwlwifi-dkms

Reboot.

Any improvement?


un-install the following using a package manager:

oem-pulseaudio-alsamixer-control-files_0.2_all.deb
oem-audio-hda-daily-lts-quantal-dkms_0.201308192259~precise1_all.deb

Then

apt-get remove --purge dkms
apt-get install dkms

apt-get remove --purge pulseaudio
apt-get install pulseaudio

restart

I also uninstalled the other packages found in the support pack


Sounds like a job for comm:

$ comm -3 <(sort test1.csv) <(sort test2.csv)
100,300,500,700
    100,4,2,1,7
    21,22,23,24,25
    50,25,700,5

As explained in man comm:

   -1     suppress column 1 (lines unique to FILE1)

   -2     suppress column 2 (lines unique to FILE2)

   -3     suppress column 3 (lines that appear in both files)

So, the -3 means that only lines that are unique to one of the files will be printed. However, those are indented according to which file they were found in. To remove the tab, use:

$ comm -3 <(sort test1.csv) <(sort test2.csv) | tr -d '\t'
100,300,500,700
100,4,2,1,7
21,22,23,24,25
50,25,700,5

In this case, you don't really even need to sort the files and you can simplify the above to:

comm -3 test1.csv test2.csv | tr -d '\t' > difference.csv


It's from Compiz.

sudo apt-get install compizconfig-settings-manager

Launch it from the dash or with ccsm and then go to Grid


If your Program exist the Parameter "Restart=always" will restart the Program. See here: https://wiki.archlinux.org/index.php/systemd for more details. Also important:

type=forking: systemd considers the service started up once the process forks and the parent has exited. For classic daemons use this type unless you know that it is not necessary. You should specify PIDFile= as well so systemd can keep track of the main process.

So if systemd need to track the process you need to create a pid-file.


Does 'rm files*' remove all matches from all sub-directories?

No. Normal globbing * is not recursive and neither is rm.

If a directory name matches, it won't be removed - you need the -r flag to delete a directory.

So it's safe to do that if you're sure you want to delete those files.

You can also make rm interactive

rm -i wordpress-*.sql

then it will ask for confirmation before deleting each file


What tool should i use to manage cybercafe on preferably latest Ubuntu?

You can try Mkahawa - An OpenSource Cyber Manager.

Link:  http://mkahawa.sourceforge.net/


Evince 3.10 toolbar hides with no obvious way to restore it on Lubuntu

Install dconf-editor
Follow path /org/gnome/evince/default/, check show-toolbar


How do I change "Show Applications" button on GNOME 3 dash?

This button is added by "Show Applications" extension, isn't it? This extension relies on view-grid-symbolic.svg icon, located in /usr/share/icons/gnome/scalable/actions folder of the Gnome icon theme. This info can be obtained when you download this extension directly and investigate its contents.

Now you have 2 ways to replace its icon.
1. You can use your scalable icon my-cool-icon.svg instead of it:

sudo cp -p /usr/share/icons/gnome/scalable/actions/view-grid-symbolic.svg /usr/share/icons/gnome/scalable/actions/view-grid-symbolic.svg.bak
sudo cp my-cool-icon.svg /usr/share/icons/gnome/scalable/actions/view-grid-symbolic.svg
cd /usr/share/icons ; sudo gtk-update-icon-cache gnome

The last string updates the cache of your icons to make your new icon appear. If it won't, restart Gnome.
This method isn't the best one, as it replaces one of the system icons, which may be used by some other application. That's why the second one is preferable.

2. You should find where this extension is located and alter its code, so it will point to another icon. First, create this icon:

sudo cp my-cool-icon.svg /usr/share/icons/gnome/scalable/actions/show-applications-extension-symbolic.svg

You can find your installed extensions in $HOME/.local/share/gnome-shell/extensions/ folder. Find the folder starting with showapplications@ within it, enter it and find extension.js file. Make a backup of it for safety, open it with your favorite editor and find the next string:

let icon = new St.Icon({ icon_name: 'view-grid-symbolic',

Replace view-grid-symbolic inside the quotes with the new one, i.e. show-applications-extension-symbolic.svg. That's it. Restart Gnome if the change doesn't appear instantly.
If it still not visible, update icon cache as explained above.

Reference


Can I install Ubuntu 16.04 parallel with Windows 8.1 on a Samsung RV513?

Sure! Go to  http://www.ubuntu.com/ and download whatever version you want, and burn it to a DVD-r or flash drive. When you boot from your live disc it will give you the option to side-install Ubuntu with Windows. It is very easy and doesn't require you to do any partitioning yourself. Enjoy Ubuntu!


Here is a small shell script,

#!/bin/bash
if `service ssh status | grep -q running`
then
    service ssh stop
    echo "ssh stopped by user"
else
    service ssh start
    echo "ssh started by user"
fi

After saving it as script.sh, run it as, (give it execution permission)

sudo ./script.sh

or without execution permission

sudo bash ./script.sh


Repeat after me:

MySQL is not crashing.

This is a common condition, and "crashing" is a common misconception... but in reality, MySQL is almost certainly being killed by the system because of a severe low-memory condition, usually caused by Apache.

sudo egrep 'kernel|oom' /var/log/syslog

Note that this is not a crash:

InnoDB: Cannot allocate memory for the buffer pool

This is MySQL unable to restart even though it tries to recover after being killed, because there still isn't 128 MB of free memory on the server, due to the apache children consuming it all.

After a reboot, nobody's connected to your web site, so the memory problem is gone.

See https://dba.stackexchange.com/a/25083/11651

You need more memory, or you need to run Apache and MySQL on different machines, or you need to configure Apache to demand less memory under load.

And for the love of a that is good and right, never use mysqltuner or anything similar. They make guesses, they give bad advice, and they are not your friend.  Leave MySQL default values as they are.


Running a mv command on large amount of data caused disappearance of other folders

I rebooted and voila!
That was weird. O.o


First of all, I suggest, if you can, to remove+purge, then reinstall openssh-client/server on the three machines, and remove each ~/.ssh, so that you start from a clean situation.

Next, follow this ubuntu wiki page that treats more specifically of ssh keys configuration.

Last, keep in mind the following issue: from debian ssh wiki:

  Login without password does not work
  if group or world has write
  permissions for the home directory on
  the remote machine.


Help debugging 404 on apt-get install apache2

197.155.77.2 works.
http://za.archive.ubuntu.com works.
http://za.archive.ubuntu.com/dists/xenial/ works.
http://za.archive.ubuntu.com/dists/xenial-updates/ works.
http://za.archive.ubuntu.com/dists/xenial/main/ works.

Either you are behind a proxy and are blocked from reaching them or their server is having maintenance or is unstable.


It's Difficult to tell what exactly it is you want to change but. If you want to change the menus in ubuntu there are three places that will be of use.

Administration > Appearance this is where you can change your theme, wallpaper and effects you can also change icons and other settings by clicking on the modify button while choosing a theme. This will create a new modified theme so you can always go back to the default.
Administartion > Main Menu here you can change what programs are shown and not shown. and you can also change the position of icons in the menu. Or create your own menu
And right clicking on the top of a menu the part on the panel/bar will give you the option of removing the menu (remember to check the name of the menu first which will be in the "about" section of the right click menu.

Hope these give give you a basic understanding of how to modify the interface to your own liking there are millions of options, tweeks and mods for ubuntu but its best to start small and know how to get back something before you hit that delete key.

Happy trails


how to create a pygtk status bar icon using quickly python

How can i add an icon to the status bar using python ? like the skype
  icon ?

It is called 'app indicator' not status bar icon, use the command

quickly add indicator for it

  and is it possible to use the default notifications like those that
  appear when connecting or disconnecting to a wifi ?

It is notify-osd,here is the guide for it


Mail Server saslauthd pam_authenticate failed

It writes it -- failed: Memory buffer error. You are running out of physical memory, disk space, swap or whatever, and pam doesn't handle it well. Which one can't be more evaluated from this log.

Check what is eating too much memory before reboot or upgrade your hardware.


How can I visit external website through ssh forwarding through a single port?

You need to do it this way:

ssh -L 8080:www.abcde.com:80 me@work

and then connect with your browser to:

http://localhost:8080/1020-39x/proprietary-documentation-blah

to get the content of your remote server on www.abcde.com.


How to list content of all .zip files in a folder and grep for a specific file?

Using zipinfo is a fine solution here. However, in general whenever you want to apply a command to a list of files and the command doesn’t accept a list of files, you can use a for loop:

for file in *.zip; do
    unzip -l "$file"
done \
| grep "\.zip\|setup"

If the file you are searching for has spaces in it like: your file, in the grep regular expression you need to escape every space with a backslash like grep "\.zip\|your\ file".


Problem installing pip: pip command not found

Install pip for Python 2 by running

sudo apt install python-pip  # pip for Python 2

and for Python 3 by running

sudo apt install python3-pip  # pip for Python 3

I would discourage you from using easy_install at all if possible; to learn more, see the many great answers at https://stackoverflow.com/q/3220404/486919. Also note that the installation instructions in the official pip documentation does not mention using easy_install at all to install pip.


Help from the command line :
C:\Users\em444>certutil -hashfile -?
Usage:
  CertUtil [Options] -hashfile InFile [HashAlgorithm]
  Generate and display cryptographic hash over a file
Options:
  ../..
Hash algorithms: MD2 MD4 MD5 SHA1 SHA256 SHA384 SHA512

So right syntax is :
CertUtil -hashfile .\ubuntu-20.04-desktop-amd64.iso SHA256


Gvfs-mount does not work with FTP anymore

I found the answer here: https://bugs.launchpad.net/ubuntu/+source/gvfs/+bug/1018806
The problem results from wrong configuration of system wide proxy. If you have the same problem you can try following commands, that will reset your proxy settings to default:

gsettings set org.gnome.system.proxy autoconfig-url ''
gsettings set org.gnome.system.proxy ignore-hosts ['localhost', '127.0.0.0/8']
gsettings set org.gnome.system.proxy mode 'none'
gsettings set org.gnome.system.proxy use-same-proxy false
gsettings set org.gnome.system.proxy.ftp host ''
gsettings set org.gnome.system.proxy.ftp port 0
gsettings set org.gnome.system.proxy.http authentication-password ''
gsettings set org.gnome.system.proxy.http authentication-user ''
gsettings set org.gnome.system.proxy.http enabled false
gsettings set org.gnome.system.proxy.http host ''
gsettings set org.gnome.system.proxy.http port 8080
gsettings set org.gnome.system.proxy.http use-authentication false
gsettings set org.gnome.system.proxy.https host ''
gsettings set org.gnome.system.proxy.https port 0
gsettings set org.gnome.system.proxy.socks host ''
gsettings set org.gnome.system.proxy.socks port 0


Empty partition menu when installing 14.04

This was caused by two things. Sometimes, when using a DVD doesn't work, you should try booting with a USB instead, it is faster as well.

The second problem I had was that there was RAID metadata that resided on the hard drive. which was preventing Ubiquity from finding it.

So, to fix these problems:

Boot from a live USB
Select "Try Ubuntu without installing."
Once booted, open up a terminal.
Clear meta data with the following command: sudo dmraid -Er /dev/sda (If your hard drive isn't located at /dev/sda then replace that argument with the location of your hard drive. You can use gparted to figure this out)
Type y when prompted to confirm.
Proceed with your install!


Elastic search curl -X GET "localhost:9200/" Connection Refused

network.host: 127.0.0.1 did the thing in my case.

I had the same exact issue with ES 6.7.1. But neither 0.0.0.0 nor localhost worked for me as network.host values.

I ran the following command:

netstat -natp

I noticed I had this line in the list:

127.0.0.1:9200          :::*                    LISTEN

So I just put the listed host and it worked.


Had the same issue (well, exact same symptoms anyway) with the upgrade, in my case dpkg apparently had a hickup sometime during the process.

This was easily fixed by running

sudo dpkg --configure -a

on the command line (you can get to a console via Ctrl+Alt+F1 and login).

Resolved the issue, and installation appeared to be in perfect shape afterwards.


How to load hex file into NXP LPC2148 microcontroller using lpc21isp on ubuntu 14.04?

you are giving clock frequency as 12000(12K) , it should be 12000000(12M since board has 12M crystal).
please make sure TX and RX pins are properly connected.


Ubuntu Software search functionality broken

All the graphical frontends I tried seem to fail to some extent... curiously, Gnome's and Ubuntu's Software Centers gave me no results, unlike you. I'm using Lubuntu 16.04, and you?

Anyway, I drew a simplistic comparison table for the searching features of some graphical & command line tools. The results may be 'qtcreator' for the actual IDE package;  'related', for packages related with the IDE or QT, like plugins, etc; and 'null' for a search with no results:

+-----------------+---------------------------+------------------------+
| PACKAGE MANAGER |      SEARCH TERM:         |      SEARCH TERM:      |
|    FRONTENDS    |      "qt creator"         |       "qtcreator"      |
+----------------------------------------------------------------------+
|gnome-software   |            null           |          null          |GUI
+----------------------------------------------------------------------+
|ubuntu-software  |            null           |          null          |GUI
+----------------------------------------------------------------------+
|software-center  |         qtcreator         |        qtcreator       |GUI
+----------------------------------------------------------------------+
|lubuntu-software |         qtcreator         |        qtcreator       |GUI
+----------------------------------------------------------------------+
|synaptic         |          related          |   qtcreator, related   |GUI
+----------------------------------------------------------------------+
|aptitude         |    qtcreator, related     |   qtcreator, related   |
+----------------------------------------------------------------------+
|apt-cache search |    qtcreator, related     |   qtcreator, related   |
+-----------------+---------------------------+------------------------+

Of the compared tools, only apt-cache and aptitude support regular expressions. Plus, you can do as you please with their output, just pipe it to any other processing tools you are comfortable with.

I thought Synaptic could make use of at least wildcards, since it uses Xapian, but this doesn't seem to work, not how I expected, nor could I find any reference to such a feature.

So once more, the console way proves itself, although I still use Synaptic for commodity reasons and some other neat features.

I'll keep looking for more info on the subject and update this answer.


How to add minimize all windows plasmoid to quicklaunch widget in Kubuntu?

Finally I found the solution.

Install xdotool sudo apt install xdotool to simulate keyboard strokes from the terminal. Reference
Create the following bash script:

#!/bin/bash
xdotool key super+d

Save it as anything, minimize.sh at your home directory.
At your home terminal write chmod +x minimize.sh to make it executable.
Create a desktop link to that script OR drag and drop the script file into the quicklaunch widget.

Now the Minimize all windows functionality is available.

This Minimize All.desktop entry to make it as launcher file:

[Desktop Entry]
Comment[en_US]=
Comment=
Exec=/home/saidbakr/minimize.sh
GenericName[en_US]=
GenericName=
Icon=
MimeType=
Name[en_US]=Minimize All
Name=MinimizeAll
Path=/home/saidbakr
StartupNotify=false
Terminal=false
TerminalOptions=
Type=Application
X-DBUS-ServiceName=
X-DBUS-StartupType=
X-KDE-SubstituteUID=false
X-KDE-Username=

Notice:

The shortcut key, in this case, super+d should be active by any mean. One of those way, is to add minimize all widget to your desktop and assigning a keyboard shortcut key to it equals to the combination declared in the bash script file. i.e in this case super+d


Please check the following :

1.sudo gedit /etc/hosts
2.if ip address and hostname not there please write them and save the file.

Please feed us back if you still facing same problem !


How to proceed for initializing repo in Ubuntu?

When you initialize a repo with

$ repo init -u <URL> [<OPTIONS>]

it will install the repo in the current directory. So if you want the repo in cm12, you have to cd in to the working directory you have created i.e  cm12.

From the official documentation:

  repo init installs Repo in the current directory. This creates a
  .repo/ directory that contains Git repositories for the Repo source
  code and the standard Android manifest files. The .repo/ directory
  also contains manifest.xml, which is a symlink to the selected
  manifest in the .repo/manifests/ directory.


Ubuntu 16.04 Window Spread is glitchy and makes the screen freeze

I had the same issue. First I used the answer from edanpose and thanks to it Unity stopped freezing, but after I pressed super+W the screen wallpaper was showing up for about a second and then everything was back to normal, but spread was not working.

Then after reading this Ubuntu Forum thread I installed compizconfig-settings-manager (CCSM) in order to check whether the scale plugin is enabled (as I understand it is related with window scaling used in window thread).

sudo apt-get install compizconfig-settings-manager

Then in CCSM Window Management, one can enable Scale window. What is interesting in my system is that it was already enabled, but when I left CCSM, window spread (super+W) started working without any problem.


Can't login to Ubuntu 16.04 lts after using software updater

I had the same problem after some Xorg component (server?) update yesterday. Reinstalling the Nvidia driver fixed the problem.


MythTV in dmesg though it is not installed

dpkg --get-selections should return nothing for packages that are not installed. The fact that it is returning something is a symptom that there are parts of the package that have not been removed.

If you try --list instead of --get-selections, you'll see the reason why the package is not fully removed. In your case, you should see rc near mythtv-backend, meaning that there is still Residual Configuration for the package.

Files inside /etc are considered configuration files and are not removed automatically when removing a package. To remove residual configuration, you need to purge the package:

apt-get purge mythtv-backend

This is the correct way of removing all configuration files, including the ones in /etc/init.


ANALYSIS

Your script is started during boot, thus not following the login process, therefor it has no environment variables or perhaps a very limited set. I trust there is no DISPLAY, perhaps not even a PATH. So the xset command fails, status stays empty, the dbus-send never reached.
You can verify my explanation by changing the xset command in your script to:

  status="$(xset q 2>/tmp/output.err | grep 'Monitor is Off')"

then reboot and check the file /tmp/output.err

  SOLUTION

I don't have the exact solution for you. You will have to do some work and various reboots and error checks.
Oh.. I urge you to change the name of your script. You named it poweroff and so did I, forgetting it is a system command. So guess what happend when I ran my script...

Ok, first action.
In the top of your script add:

  export DISPLAY=:0.0
  env > /tmp/output.log

Within the while-loop add

  sleep 5

command to prevent a huge /tmp/output.err file.

Reboot your system and check the output files in /tmp. If there is an empty output.err, then the xset command did not fail. If it did fail, you need to define more environment variables in your script. Perhaps one or more of the XDG_ variables, sorry but I'm not very experienced with X11.
Good luck !


One reason that the filesystem may be showing full when there is space remaining is space reserved for root. Once you've determined what is taking up all the space You'll need to free some space up or resize the instance.

More sources:
https://serverfault.com/questions/330532/xvda1-is-100-full-what-is-it-how-to-fix


Ubuntu Studio 20.04 desktop environment fails to load

After raking my brains for days on end I've finally figured out that it has something to do with gnome extensions. I've restarted the machine with and without extensions turned on several times and the test is conclusive: every single time I have extensions turned on the desktop would fail to load.
Now it's about figuring out whether it's one in particular, several working together or the whole extensions functionality, but at least now I have my machine back...
I hope this helps others who might find themselves in this pickle.


You can make use of grep's return status.

systemctl status asd.service | grep 'active' \
    && status=active \
    || status=not_active

if [ "$status" == "active" ]; then
    [...]
fi

or even easier:

test $(systemctl status asd.service | grep 'active') \
    && echo "$SERVICE was active"

or if you prefer if:

if $(systemctl status asd.service | grep 'active'); then
    echo "$SERVICE was active"
fi

Anyways, take care about the keywords inactive, not active, active (exited) or alike. This will also match your grep statement. See the comments. Thanks @ Terrance for the hint.

Update:

No need for grep. systemctl has the command is-active included.

systemctl -q is-active asd.service \
    && echo "$SERVICE was active"

or:

if systemctl -q is-active asd.service; then
    echo "is active";
fi


Is it ok to install Java 7 in Ubuntu 12.04?

Yes, it's perfectly OK to install Java 7 on Ubuntu. In fact, you can install and use multiple versions of Java, from multiple vendors, at the same time!
The reasons some don't recommend Java 7 as a replacement for Java 6 yet, for end-users, include:

Java 7 is still relatively new and "maturing"
Most of the Java apps/code out there was written for Java 6 and works perfectly with it
Java 7 should be able to run the above too, but rarely there's a bug and it fails or causes problems.

As this link from May 2012 explains, while Java 7 has been available for developers since mid-2011, Oracle only started upgrading Windows users to Java 7 in May 2012, and it is still offering and recommending Java 6 to Linux and Mac users.
Bottom-line: if you are a developer, get Java 7. If you are a user, you can get it too but keep Java 6 around. This question explains how you can install multiple Java versions and use a graphical utility to chose which is the "default" Java


Login with your currentusername, open a terminal and type:

sudo passwd root

Enter a password for the root account, then logout, press Ctrl+Alt+F1 to open a text console, login as root (username: root, password: "the one you typed above") and run:

usermod -l newusername -m -d /home/newusername currentusername
exit

Press Ctrl+Alt+F7 to return to graphic console and login as newusername.

To change the user's display name (the one that appears at the login screen), go to System Settings -> User Accounts then click the display name on the right-hand side of the dialog.


As far as i understood your goal is to save your files.
One possible solution is to install Ubuntu on new partition (keeping your current installation and files on different.) This will allow you to access your files and copy to exernal USB/HDD, if the data is not to big or you have enough free space on external HDD.
After this step reinstall, "the broken partition", in case you didn't found how to fix it.


How to configure extra buttons in Logitech Mouse

You're going to need several applications for this, to install them run
sudo apt-get install xbindkeys xautomation xev

or
sudo apt-get install xbindkeys xautomation x11-utils

edit: xev was merged into x11utils, as of Ubuntu 14.04 or greater.
Step 1
You need to find the button numbers for the buttons on your mouse.  Run xev.  You will see a litle white windows appear, put your mouse in it and press your mouse buttons (it's best to do this one button at a time).  You should get output like this for each button:
ButtonRelease event, serial 41, synthetic NO, window 0x4c00001,
root 0x2e9, subw 0x4c00002, time 25804905, (31,28), root:(821,80),
state 0x110, button 1, same_screen YES

(note: xev also capture mouse movement so you might need to sift through mouse movement events to find your button events; e.g.: xev -event mouse | grep Button --before-context=1 --after-context=2)
This is what is important from that output: button 1.  That tells us that particular button is button one.  I would store this in a .txt file for now.
Step 2
Create the xbindkeys config file using:
xbindkeys --defaults > $HOME/.xbindkeysrc

Next we need to add the key/button bindings to the config file.  You can open this file with gedit $HOME/.xbindkeysrc.  This is where the fun begins.  We are going to use xte to set bindings to our buttons.
To make a button act as Ctrl we would add:
"xte 'key Control_L'"
b:1

This would bind Ctrl to mouse button one.
If you will tell me the button numbers of your buttons and what you want each to do, I will write the script for you.


You will be provided with a OS selection menu ,the Grub2 menu from which you can select the OS to which you want to boot into.Ubuntu will be the default OS  but it can be changed to  Windows if you like it that way.

Check out the following image of Grub2 (Ubuntu + Windows XP)

More info on GRUB2


First, an obligatory warning. It is usually a very bad idea to try to parse HTML with simple tools like regular expressions. That said, in this case, if you are sure that what you want will always be between file: and the first ,, you can use:

wget -O - http://vodlocker.com/embed-wrdlm4dbigu4-850x450.html 2>/dev/null |
    grep -oP 'file:\K[^,]*'

You need the -O - to tell wget to print the html to standard out instead of saving to a file. This is then piped through grep with Perl Compatible Regular Expressions (-P) and -o to tell it to only print the matched portion of the line. The regex itself looks for file: and then discards it (\K) and then 0 or more non-, characters ([^,]*). The 2>/dev/null discards wget's messages.

Note that in the example URL you gave, there are three matches:

$ wget -O - http://vodlocker.com/embed-wrdlm4dbigu4-850x450.html | grep -oP 'file:\K[^,]*'
"http://77.81.98.228:8777/n2ceexa2lo4pcnokaldsf4o64qg7le7rp2xxamcxtdebwqbtaozwssfetq/v.mp4"
"http://vodlocker.com/dl?op=get_slides&file_code=wrdlm4dbigu4"
"http://vodlocker.com/images/vodjw_logo.png"

If you know you only need the first one, use -m 1 to tell grep to stop after the first match:

$ wget -O - http://vodlocker.com/embed-wrdlm4dbigu4-850x450.html 2>/dev/null |
    grep -m1 -oP 'file:\K[^,]*'
"http://77.81.98.228:8777/n2ceexa2lo4pcnokaldsf4o64qg7le7rp2xxamcxtdebwqbtaozyasfetq/v.mp4"


It is possible http://ipinfo.io/ip sometime fails and returns nothing.
Anyway, you should at least do a minimum check on $currextip value before passing it to sed.

Adding something like this should be enough:

if [ -z $currextip ]; then
    echo "Something went wrong with ipinfo.io!"
    exit
fi

I don't know if this is really the cause of your problem, but you should always check for failure cases.

As a side note, you should not use the ":" separator with sed in this context, because if you get an IPv6 at some point things could get really wrong.


Try to use netstat -tunap or netstat -tunlp before the program starts and after the program starts.


Lost Windows 7 boot entry after installing Grub customizer

You should repair your windows installation with your Windows bootable DVD, using the Repair your computer option, and after you finish with this one, you can download Boot Repair CD iso image and burn it on a regular CD or put it on USB key via Unetbootin. I assume you still have the installation disc for WIN7?

Oh, useless to say that you should get rid of 'grub-customizer' as soon as you can.

Boot Repair CD comes in 2 versions, one is for 32bit OS and the other for 64bit OS. So if you installed Win7 64bit you'll be needing boot-repair-disk-64bit.iso image, and the 32bit iso image for Win7 32bit.

After you make sure that you can boot into Win7, you can place your new Boot Repair CD in tray or use the USB version and restart your computer. Allow the CD to load its system, and choose the Recommended Repair option once you are in the live session with Boot Repair CD.

After you restart your computer again and, hopefully, boot into Ubuntu you should run the sudo update-grub command so Ubuntu be able to list your Windows in the boot menu.


If you're running Ubuntu Touch on your tablet, all installed apps are available in the Dash (you may have to tap on the "Show all") or the Desktop Apps scope (you may have to swipe left to bring it up).


How can I see all versions of a package that are available in the archive?

As far as I understand your requirements, the madison option for apt-cache does what you want:

  madison /[ pkg(s) ]
  apt-cache's madison command attempts to mimic the output format and a subset of the functionality of the Debian archive management tool, madison. It displays available versions of a package in a tabular format. Unlike the original madison, it can only display information for the architecture for which APT has retrieved package lists (APT::Architecture).

On my computer:

$ apt-cache madison f-spot
    f-spot | 0.7.2-1~ppa~lucid0 | http://ppa.launchpad.net/f-spot/f-spot-ppa/ubuntu/ lucid/main Packages
    f-spot | 0.6.1.5-2ubuntu7 | http://ro.archive.ubuntu.com/ubuntu/ lucid-updates/main Packages
    f-spot | 0.6.1.5-2ubuntu6 | http://ro.archive.ubuntu.com/ubuntu/ lucid/main Packages
    f-spot | 0.6.1.5-2ubuntu6 | http://ro.archive.ubuntu.com/ubuntu/ lucid/main Sources
    f-spot | 0.6.1.5-2ubuntu7 | http://ro.archive.ubuntu.com/ubuntu/ lucid-updates/main Sources

I hope this is what you need. It also includes the ppas.


How can I remove my hard drive icons from my desktop?

I found this while searching in google

How to hide all desktop icons in 12.04 and later?

http://ubuntuforums.org/showthread.php?t=1871789


Would booting 12.04 from external HDD give me problems for developing kernels for Android 4.12 and 4.2.2?

depending on your available bios options You can set up the external drive with its own grub bootloader, then that bootable drive will not care what you do on other drives


Ubuntu Local Network Share - Failed to mount Windows share: Permission denied

The two most common causes of your error message are:

[1] You are not passing the samba password when asked for the "registered user" credentials.

You create that password by adding the user to the samba password database - and I will use my own as an example:

sudo smbpasswd -a morbius

[2] Since the share that was created allows guest access the more likely case is the path to the shared directory does not allow access to the shared folder. The shared folder itself may allow access to guest but the path to that folder may not. For example if the folder is mounted to /media/morbius/Media then only morbius will have access to Media.

I would suggest that you edit your original question and add to it the output of the following command so the folks here can see where the folder is located:

net usershare info --long


There is a good tutorial on the web, which solves this problem:
http://andrewwilkinson.wordpress.com/2012/01/23/integrating-python-and-javascript-with-pyv8/

The steps that worked for me where a bit different though:

sudo apt-get install scons libboost-python-dev
svn checkout http://v8.googlecode.com/svn/trunk/ v8
svn checkout http://pyv8.googlecode.com/svn/trunk/ pyv8
cd v8
export V8_HOME=`pwd`
cd ../pyv8
sudo python setup.py build
sudo python setup.py install


Really it is available. You need to run sudo apt-get update first.

And then run sudo apt-get install libpam0g:i386


lxpanel won't save width settings when it's at the left edge

It's a known bug and I hope they will adjust it in the next versions. Meanwhile, you can install the 0.7.2-1 version that has not this bug and it is quite the same of 0.8.1 (at least by the graphical point of view)

You can download the .deb package for installation here:
i386: https://packages.debian.org/jessie/i386/lxpanel/download
amd64: https://packages.debian.org/jessie/amd64/lxpanel/download
lxpanel-data: https://packages.debian.org/jessie/all/lxpanel-data/download

Before you install the packages, you must remove the current version:

sudo apt-get remove lxpanel-data lxpanel

then you can install lxpanel-data and then lxpanel.

To avoid system auto-update to 0.8.1 you can launch

sudo apt-mark hold lxpanel
sudo apt-mark hold lxpanel-data


Pass-through of Marvell 88SE9230 to Xen guest with AMD-V iommu

The standard Xen emulated IDE will appear as ada0 while the passthrough SATA device will also appear as ada0. This results in one disk shadowing the other. In /dev/ only one ada0 entry will be seen.


How Recover data from a server that crashes on startup?

If you're not reading the drives, it might be a partition table problem.
I would recommend running a live CD on USB (or CD if you roll that way). And then running testdisk.

From testdisk, you can repair your partition table, recover files, and even recover some deleted files which haven't been overwritten a lot.

Some links:

http://www.cgsecurity.org/wiki/TestDisk_Step_By_Step
http://www.cgsecurity.org/wiki/Data_Recovery_Examples

EDIT: Actually your lsblk suggests your partition is detected properly at /dev/sda1 for the server's root directory I'm guessing. Is the data you want to recover in /dev/sda or /dev/sdb or /dev/sdc? Either way, testdisk should still work for repairing partition tables and recovering data.


How do I completely remove KDE and nothing left behind?

If you have personal files you want to keep, backup your personal files from your /home folder.  Then run the Ubuntu LiveUSB installer.  Install Ubuntu on the partition that has the KDE installed.

Since you say you have a dual boot with Windows and KDE, you'll be able to easily identify the KDE partition by the partition type, ext4.

The fresh install process will remove all the systemwide folders and replace all the Libraries and settings for Ubuntu.

When you perform the install, you'll have an option to format the partition or install to the partition without formatting.  If you use the latter (install to the partition without formatting) it won't touch your /home folder.  It'll just do as you asked for, completely remove KDE and have it replaced with Ubuntu.

You're find the option for picking the previous (kde) partition under the Something Else install choice.


Failed to get the adb version: Cannot run program & Cannot allocate memory

Your system is 64bit?
if so, install the 32bit library

apt-get install ia32-libs


How can I view or start Java Web Start Applications?

Just use javaws as you normally would.

javaws /path/to/your.jnlp

If you want to open in nautilus:

right click on your file -> Open with other application... -> Use custom command -> /usr/bin/javaws


Assuming you are not concerned about someone using recovery tools to get the data back ( and if you are you shouldn't be using rm ), then just format the disk.

mkfs.ext4 /dev/md0

Also it sounds like you are currently using ext3, which takes quite a while to delete large files.  In the future, you should use ext4 which does not have this problem.


Cant install libsdl2-dev or cmake glfw.. (libxinerama-dev problem)

I also ran into same problem while installing the glfw lib. This is how I solved it:

I navigated into my home directory using:
cd ~

I then ran:
sudo apt-get install libxinerama-dev

I navigated again to the directory of glfw and ran:
cmake -G "Unix Makefiles"

This time the error was xcursor lib not found. So I repeated the above steps and installed the xcursor lib with:
sudo apt-get install libxcursor-dev

After this I navigated back to the glfw  directory and the cmake command was successful.


Ubuntu 10.04 still supported but 10.10 not

Because 10.04 is a long term support relise and 10.10 is a regular one. Read from Ubuntu wiki about it: LTS


The recently updated Firefox 70.0 has problems rendering many web sites. Clicking on links sometimes doesn't take you to the desired web location. This has to do with a new Firefox design having to do with "storage".

After much testing, I've come up with this solution...

in Firefox 70.0, go to about:profiles
note which profile is the current, in use, profile
for the Root Directory click the Open Directory button
quit Firefox
move the storage folder out to another location
restart Firefox, it'll rebuild this folder automatically
try the web site that was giving you problems and see if it's working now

Update #1:

Pending release of Firefox 70.0.1 is also supposed to resolve the problem.


Do I need nvidia driver for Dell Inspiron 5720?

You may want to look at these resources:
https://wiki.ubuntu.com/Bumblebee

I believe your laptop has the on-demand discrete GPU feature called "optimus"

This is currently not well supported by NVIDIA under linux. Bumblebee gives you a work around.
NVIDIA has made indications that they are working on a Linux Optimus driver, but it has yet to be released


USB memory stick is "broken" after files are copied

As @falconer pointed out, 80MB/sec is impossible on USB2.0 and also very-very unlikely on USB3 for a pendrive.

The reason of such fast speed is probably writing cache. While the Copy Dialog shows you 80MB/s, the actually write speed is 5-6MB/s and OS caching everything rest and write it later. So even Copy Dialog report about files are copied, they're actually not.

OS still writing on the disk and if you press Unmount option on drive it will tell you that there are operations with the drive and you need to wait. After a several minutes(or more if files are big ones) it actually finish write data on drive and make pendrive inactive. Than you can eject drive and open files on other PC or TV.

There are two posts questions that may help you with disabling writing cache:
How to switch off caching for usb device when writing to it?
and
https://superuser.com/questions/526248/turn-off-write-cache-on-all-usb-external-drives-debian-ubuntu-linux

I used the second one for my problem and it helped me. I have only one hard disk drive in my laptop(/dev/sda), so any other drive is removable. Also I have 2 usb ports so I can connect 2 external drives maximum(/dev/sdb and /dev/sdc) so i've added to /etc/hdparm.conf

/dev/sdb {
        write_cache = off
}
/dev/sdc {
        write_cache = off
}


How to change both the text of the command prompt and the color?

You should add reset code after changing color.
\033[00m resets your prompt color.
In addition, your PS1 makes your prompt []xyz$ .
If you want xyz$  without [], please set as below:
PS1="\033[0;32mxyz\033[00m$ "


Create new directories with 10 text files in them, and in these files 1 random number

Actually, I think that you should do your own homework, and your question includes some of the knowledge you need.

You understand loops.
You must do a loop inside your first loop.
You should investigate how to get a random number.

Despite this, here you have a oneliner that fits your requirements, if I haven't misunderstood you:
for i in {1..5}; do mkdir "Directory${i}"; for j in {1..10}; do echo $RANDOM > "Directory${i}/File${j}"; done; done


I can't log in to gmail in ubuntu on an specific ISP

Try disabling 2 step verification, then logging in. Who is your ISP at home and at the office?

Can you login via a proxy?

And what about other browsers, is this just Chrome(ium) or Firefox or all of them?


Go into the BIOS, and change the boot order to boot from the USB pen drive.  See image below.

Note: Image is for instructional purposes only, your actual options maybe different.

Once done press F10 to save and exit.

Press F10, then Enter to confirm. The netbook will reboot.

If you still can't boot from the USB, You may have to disable Boot Booster in the Boot section.


Puzzling message from Startup Disk Creator

It's a bug. Specifically this one which has a patch to fix it, but hasn't been applies in Ubuntu yet.


How to run a specific version of Qt with Notepadqq

I'm not 100% sure why, but it looks like the application GUI behaves differently when installed using the PPA compared to when it is installed as a snap. I have seen this with another application.

If you carry out the following steps, you should end up with notepadqq using a non-native open/save dialog in Ubuntu 18.04.

Uninstall the current notepadqq

sudo apt remove notepadqq

Clean up the system by removing the PPA

sudo add-apt-repository -r ppa:notepadqq-team/notepadqq
sudo apt update

Install notepadqq as a snap

sudo snap install notepadqq

Launch notepadqq and check the open/save dialog. On my system, the non-native dialog appears.


how to add persistent route on a container

Ubuntu is now based on Netplan service to configure network. Based on the official documentation https://netplan.io/examples, here a basic sample :

network:
  version: 2
  renderer: networkd
  ethernets:
    enp3s0:
     addresses:
       - 192.168.1.10/24
     #gateway4:    # unset, since we configure routes below
     routes:
       - to: 0.0.0.0/0
         via: 192.168.1.1
         metric: 100
       - to: 192.168.2.0/24
         via: 192.168.1.2
         metric: 100

This file should exist or must be created under /etc/netplan/ with a .yaml extension (e.g. /etc/netplan/config.yaml). Don't forget to use command sudo netplan apply to apply configuration.


This button is not for manual calibration. To calibrate a monitor, you need a special device called colorimeter.

If you don't own such a device, the best thing you can do, is to do a websearch for available color profiles you can try (try, because not every panel is the same, so someone else's color profile for your monitor might make things even worse).


Nautilus 18.04/20.04, hide specific drives in Other Locations

Nautilus does not display volumes in the location pane if those volumes have to be mounted elsewhere than in /media
You can 'hide' a partition by specifying a mountpoint elsewhere than in /media in the fstab file. Of course, lets play with mount option to not mount those volume at boot.
The lines in fstab should look like this :
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
  /dev/sdXY      /mnt/uniq       zfs     noauto          0       0
# mountpoint should be uniq
# noauto, parition will not be mounted at startutp, not mouted with mount -a
# fsck option 0 & 0 But why not use recommended settings for zfs

Example with /dev/sda9
sudo mkdir /mnt/hidesda9
echo "/dev/sda9 /mnt/hidesda9 zfs noauto 0 0" | sudo tee -a /etc/fstab
sudo mount -a


Ubuntu 16.04.1 WiFi works only after several reboots

If you can change the router encryption, change it to WPA2-PSK or WPA2-AES only, no WPA, WEP, or TKIP.

Then disable UFW as it is blocking mDNS traffic.

Reboot and see if the issues are gone, if not then we can disable the power management with
sudo sed -i 's/wifi.powersave = 3/wifi.powersave = 2/' /etc/NetworkManager/conf.d/default-wifi-powersave-on.conf

Then reboot again and see if it is fixed


Open Folders

Click on files on the top Ubuntu bar, and choose Preferences.

Click on the Behavior tab, and change the behavior .

If its the right click that you changed, you probably changed the mouse to left handed.  If that's the case, then open dconf editor.  If its not installed then, just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command(s) below:

sudo apt-get install dconf-tools


How do i run different scripts parallely using shell

You can do it by

script1&script2&script3


It's possible that they're using some fingerprinting algorithm (i.e. the particular behavior of that ethernet interface such as timing etc.) to determine that the physical host has changed, or they could be polling the various ports on the router (I believe this is possible using SNMP) to determine that it has changed in too short a timeframe.

Think of this from the other angle, and Google "prevent MAC address spoofing" and you'll see a few vendor-specific solutions.

As to how you can get around it, the only possible way seems to be setting up a network bridge (i.e. internet sharing) on one of the existing computers to connect your laptop.


Boot-repair has served me well in the past when I had problems with GRUB. The easiest way is to create bootable drive, and boot directly from it. As the interface suggests, the "Recommended repair" usually does the trick and you don't have to do anything.

One thing that you may want to do before rebooting is to look at how the physical drives are partitioned and named. A very handy command for that purpose is lsblk. I wish I had known about that command a long time ago!


Linux has mediocre HFS+ support: the open-source kernel module defaults to read-only mode because write support is considered unstable (and thus potentially destructive).

The situation is even worse for integrity checks and recovery. You should use the tools that Apple provides for its home-grown file system or commercial tools that specialise in HFS+ undeletion or data recovery. These should give you better chances of success for file undeletion than Photorec. The former leaves traces behind that allow a complete and easy recovery if the freed blocks weren't reclaimed while the latter looks for known content type patterns in arbitrary blocks of data (that may or may not contain a valid file system).


How to change video drivers from the CLI

Yes sudo apt-get install nvidia-340 would be how you switch to the Nvidia-340 driver. Basically you're installing the drivers like software and the old driver is automatically uninstalled.


Crashing after resuming from suspend - Since upgrade to 14.04

I have had similar problems converting very old PC to Ubuntu.  In some cases, it worked, in other ones, not.  In my case, it was a question of ressources.  I finally used the lightweight version of Ubuntu, Lubuntu.  This eliminated the crashes I had and that look similar to the symptoms you describe. My recommandation therefore is to give Lubuntu a try.


Dual-booting my system with Windows 7 and Ubuntu and booting the same Windows OS into a VM while running Ubuntu?

If i understand you correctly, you want the actual windows installation to be available as  your vm. Or else constantly sync  all changes with your vm install on ubuntu. If that is the case, then the answer is it cannot be done. This would envolve writing any changes to the vmware environment to the base windows installation. Basic os architecture will not allow that.

The only  solution I can think of is to keep all your user files in your windows  and vm synced with a cloud syncing solution. Something like Ubuntu One or Dropbox. In that way, changed files and documents will be available in both windows native as in windows vm


Before going to do that you need to start the unoconv listener then only it will start.
open your terminal with CTRL+ALT+Tand start the listener as

unoconv --listener

Then try again with your operation of conversion.

NOTE: make sure that no other process using the listener, If any process do so , kill that process to assign the listener to current conversion.

hope that helps.


how to run an appimage app stored at a fat32 storage

I provided a link from the official website but here is a demonstration on how to do it either from the desktop GUI or the bash terminal:

Using the Terminal

Open a terminal
Change to the directory containing the AppImage, e.g., using cd <my directory>
Make the AppImage executable: chmod +x my.AppImage
Run the AppImage: ./my.AppImage

Using the GUI

Open your file manager and browse to the location of the AppImage
Right-click on the AppImage and click the ‘Properties’ entry
Switch to the Permissions tab and
Click the ‘Allow executing file as program’ checkbox if you are using a Nautilus-based file manager (Files, Nemo, Caja), or click the ‘Is executable’ checkbox if you are using Dolphin, or change the ‘Execute’ drop down list to ‘Anyone’ if you are using PCManFM
Close the dialog
Double-click on the AppImage file to run

https://docs.appimage.org/introduction/quickstart.html#ref-how-to-run-appimage


There are lots of ways you can improve boot speed for Ubuntu.

get ubuntu certified hardware(or try :D)
get an ssd
limit start up services
don't use wubi

Boot time on Linux is an important feature especially on a laptop.  I remember when decreasing the boot up time was an important feature of Ubuntu just a few revisions ago and while I may not be able to tell you exactly the reason why your ubuntu installation boots slowly I can tell you mine boots quickly.

This might help figure out the offending application that is hurting your boot time

sudo apt-get install bootchart

After you reboot look in /var/log/bootchart

I believe you can also use log viewer.

After you get that post your results and I will try and help you.

Also post your output of

dmesg