Does the installation of GNOME 40 flatpak apps slow down a 20.04 system significantly?

Flatpaks nor snaps should slowdown the main operating system as long as the applications are not running. When they are running, they will use system resources, but that is also true for applications regularly installed using APT.
The main difference in resource usage will be in memory footprint. These applications are in principle containerized, and each package needs to provide in its own dependencies, to some extent however provided by other snaps or flatpaks. To run Gnome 40 flatpak applications, all the GTK4 libraries they need, must also be loaded, separate from these provided by the operating system. This is, for flatpak, done through "dependent" flatpak packages, the Application Platform packages that you mention. These can be shared among flatpaks, allowing to reduce the redundancy within the flatpak environment.
Once running, flatpak or snaps should not be slower than regular APT packages. At that point, they are just running code like any other apps, however running in a confined environment as setup by the flatpak or snap framework. Only when permitted do they access the resources of the installed operating system.
Not sure what is going on with your system, but this should not be because you are using Gnome 40 flatpaks. As said in the comments, it is true that "Flatpak and Snap are synonyms for redundancy, and therefore, wasted resources..." but with your 12 GB of RAM, that should not be in the order that it slows down your system. With or without flatpaks installed, a freshly booted Gnome Shell based system should not be using more than 1 GB of RAM (as indicated by the column "used" in the output of the command free -h --si).


ncmpcpp and mpd: jump to marked song after finishing current song

select the song that you want to add, press a choose current playlist then choose after current song


Share a NTFS folder with another Ubuntu user

1. Add both users to the same group.

To make both users have access to the folder with the same permissions you need to add them to the same user group.

Find out the group of your user.

The easiest way to achieve this is to add the second user to your own user group. Therefore you have to find out your own group. It usually has the same name as your username. You can find it out in a shell by typing the following when logged in as your user:

groups

The output should be something like this:

<somegroupname> adm cdrom sudo dip plugdev lpadmin sambashare

The first entry in place of the <somegroupname> is your primary group, which is the user group by default.
Add the second user to the group.

To add the second user to your user group you type while logged in as root:

usermod -a -G <group> <user>

If there was no error, there will be no output.
Find the UID and GID of your user and group.

You will need to sed owner user and owner group the partition should be mounted with identified by their ID. Find the user ID by typing

id -u

while logged in as your user. Find the group ID by executing

id -g

while logged in as your user.

2. Make sure the partition is mounted with the correct umask for your needs.

Determine which umask (Wikipedia has a very detailed explanation, if you are interested) would be appropriate.

In short the umask is the reverse mask of the usual unix filesystem permissions, which are basically split up into read, write and execute, in short r, w and x. Those are represented on filesystem level by octal values of r=4, w=2 and x=1. If you want to combine permissions you simply add the values, so a value of 6 (which would look like "rw-") would allow a user to read and write to a file, for example.

There are three groups of these permissions for each file or directory on your system, the first one regarding the owner user of the file, the second one regarding the owner group and the third one regarding everybody else. If you type ls -l, you can see the permissions of each file in the folder by an output like this:

-rw-r----- 1 david coworkers 241232 Apr 10 21:17 test.txt

The permissions in the above line would be split into the first -, which is the bit referencing the type of the file (i. e. directory or link), rw-, r-- and ---, which would allow the user david to read and write to the file and anyone in the group coworkers to read it, while anybody else would not be allowed to do anything with the file.

Having that in mind, you will conclude that you primarily want to set the part of the umask regarding the group, because you added your wife to yours and therefore can manage the permissions for both of you by managing the permissions for the group.

As I said, the umask is the reverse mask of the permissions - which means you take the number 8 and subtract the value of the permissions you wish to apply, respectively for the user, group and others, i.e. 5 for read and execute. These are the default permissions set for the group and others by most linux distributions - files created with this umask end up with 4-permissions, direcories with 5.

Basically you want to grant your wife and yourself full access to all files so I would recommend to use a umask like 002 or 003.
Find out which partition you need to configure / check.

There are plenty of commands you can execute to find out which partition or device you will need to check and maybe configure. The output of df, blkid or fdisk -l should help you find the right one. I usually use

df -h

which should output something like this

Filesystem      Size  Used Avail Use% Mounted on
/dev/sda2       8,0G  6,5G  1,2G  85% /
/dev/sda3       233G  137G   96G  59% /mnt/data

and

blkid -t TYPE=ntfs

which would result in something like this:

/dev/sda3: UUID="B474E96674E92BB4" TYPE="ntfs"

Edit your /etc/fstab file.

Open the fstab file with an editor while logged in as root like this

vim /etc/fstab

and find the line regarding the ntfs partition, identified by the UUID, the device name (i.e. /dev/sda3) and/or the mount point (i.e. /mnt/data). Change it to something like the following (using the information you gathered previously):

# <file system>         <mount point>   <type>  <options>                        <dump>  <pass>
/dev/sda3               /mnt/data       ntfs    uid=1000,gid=1000,umask=0003     0       0

OR

# <file system>         <mount point>   <type>  <options>                        <dump>  <pass>
UUID="B474E96674E92BB4" /mnt/data       ntfs    uid=1000,gid=1000,umask=0003     0       0

either defining the partition by it's device name or it's UUID.

Be carefull to not delete options that are already set, though of course there should not be any duplicates in the options section of this partition.
Reboot your PC.

If I recall correctly, this will be the only option because the unix permissions are not saved to the NTFS structure permanently but the system only remembers them for the time it is mounted. So setting owners, groups and permissions with chown, chgrp and chmod will probably not help on the long run but only for the time until the device will be unmounted once again - which at the latest will be the next time you shutdown your PC.

[EDIT FOR COMPLETENESS]

As my first comment suggests, there might be a method to save unix permissions to an ntfs file system, but I cannot verify this for I have not tried it myself. I personally use the way I described above.


Getting NVIDIA to work after installing Ubuntu Studio Packages

Solved!

After sudo apt-get purge nvidia* I forgot to autoremove the rest.

So:

sudo apt-get purge nvidia*

then:

sudo apt-get autoremove
sudo reboot

Upon reboot the nouveau drivers loaded in full HiDPI.  After login, I used the "additional drivers" app search and loaded the latest Nvidia drivers and rebooted.

All good!


This usually means that PHP is not being interpreted because the webserver does not know how to handle it. Is mod-php installed? Try the following:

$ sudo apt-get install libapache2-mod-php5
$ sudo a2enmod php5

Did you try to configure FCGI, maybe? In that case there is probably an error in your configuration.


Is there a feature like Alt + Tab for groups?

I understand what you are asking but I don't know of any way to do exactly what you are asking, however with Unity you can press Super + [NUMBER] to show the most recently open applications in a group and then the same combination again to show all of the open windows of that app, using the scale plugin.

e.g. Chromium is the second app down in my launcher and if I were to be currently in a different app but wanted to switch to Chromium I would press Super + 2 and I would be there, I could then press it again and it would show all of my windows.


Help with simple macro for ubuntu/centOS

In Linux you usually use a bash script to do something like this. In order to get a mouse click, you need to install xdotool:

sudo apt install xdotool

Now, you can write a simple bash-script. Just run

nano bash_script.sh

Now paste following code:

#!/bin/bash
while true
do
  sleep $((120 + RANDOM % 60))
  xdotool click 1
  sleep $((60 + RANDOM % 60))
  echo '0'
  sleep $((10 + RANDOM % 10))
  xdotool click 1
done

Run sudo chmod u+x bash_script.sh in order to make your script executable.
Last, you can start your script with

sh bash_script.sh


Open gedit and paste the following (ignore "):

  "#!/bin/sh -e

  sudo startx

  exit 0"

Save it as anyname.sh (in this example I have saved this file in "dir" folder which is present in your home directory). You might need to change the permissions to this file. To do so type:

chmod a+x /home/username/dir/anyname.sh

Then type:

sudo gedit /etc/rc.local
Add the following above the line "exit 0":

sudo sh /home/username/dir/anyname.sh
Restart and see if it works.


Touchpad stops working after a while, Ubuntu 14.10, Dell Latitude E7440

If the Touchpad stops working after a few mins. you please just connect with you external mouse and check the mouse pointer is working or not.
The issue may be of driver problem, This is the one of a temporary solution to overcome from restarting your machine.


TP Link WN725N driver for Ubuntu 16.04 LTS running kernel 4.4

try the following steps, it worked for me -

sudo apt-get update
sudo apt-get install linux-headers-$(uname -r) build-essential git
git clone https://github.com/lwfinger/rtl8188eu
cd rtl8188eu
make all
sudo make install
sudo insmod 8188eu.ko


Trying to update python3.9 giving errors

I had a similar problem with a Python upgrade, but also including dependencies outside the repository. Honestly, the best, most efficient way to solve this is to completely remove it and do a fresh, clean install.
edit: I don't know if the spelling in your post is the same you enetered into your terminal, but your first problem is you spelled the package wrong.


What is reason for apparmor="DENIED" operation="open"

The mission-control-5 process tried to open and read the /home/jagat/.config/dconf/user file and Apparmor stopped it.

I'm not sure why mission-control wanted to read that file, but unless you have been tinkering with apparmor or think you are experiencing problems because of this, you shouldn't need to take any actions.


How do I get rid off undesirable Java version?

Problem solved by running: sudo apt-get remove openjdk-*


From where I'm getting programs in Unity launcher?

Slow method: Search the entire filesystem for files named *harm.*esktop (PyCharm may be capitalized differently; desktop case may vary):

ls -R / | awk '
/:$/&&f{s=$0;f=0}
/:$/&&!f{sub(/:$/,"");s=$0;f=1;next}
NF&&f{ print s"/"$0 }' | grep "*harm.*esktop"

Hope this helps!


Gimp: Can't use fill bucket to fill selection

Looking at your window title, you are working in "indexed colour" mode, which means your file has a limited colour palette. This saves space, and is why these files take very little memory to load.

If you want to edit the file, with all colours available, you should first switch to RGB mode, else the colour simply isn't available in your file :)


How to retrieve files from a Windows partition from Ubuntu desktop

One thing you should be able to do is go under

Places -> Name of your Drive -> Opposite Click -> Mount

and if it does mount you will then be able to access it, see what's on it just like you would be able to do in Windows. If that can happen then it's a simple matter of drag and drop.

If you cannot see it in your Ubuntu partition then you can use an external USB HD like a Western Digital backup drive or something like that and just copy all your files/folders to that external drive, then plug it in your Ubuntu partition and drag and drop it to that...other than that there really isn't any easy way of doing it...


File libsane.rules is completely missing

When I upgraded from 14.04LTS to 16.04LTS my scanner did not work. The upgrade deleted file 40-libsane.rules and replaced it with 60-libsane.rules without offering to keep/rename the old file. The new 60-libsane.rules did not contain my earlier edits to 40-libsane.rules. Redoing the old edits to the new 60-libsane file solved my scanner problem.


Nokia Bluetooth headset Bh 503 not recognized

(comment to answer solved issue)

I just connected my bh-503 few days ago with precise, you have to turn-off and turn-on again your headset, when turning on hold the button until the lights turn into blue and green, scan the device. that works for me. but the audio is very awful. it works great with lucid. – erickjohncuevas Jan 23 at 10:25
It's just working, I Don't have sure if it's because the packages or not. – euDennis Mar 9 at 0:14


Installing Ubuntu onto new totally blank laptop drive

Just create a live DVD or flash drive, and boot into it and install as usual. There really isn't much to do about the drivers if they aren't supported out of the box without manually compiling them.


Libre.fm is part of the LastFM plugin

Choose Edit - plugins and click of the Last.fm plugin.  You then will have the preferences button visible.  From the popup-dialog you can hide/show both services.


Pre Installed Windows 8 on one hard drive and Ubuntu 12.10 on separate hard drive. Is this Possible?

I am sure it is very common method to install Ubuntu. But dual booting Windows 8 with Ubuntu might be bit tricky.

This AU post should help you (even if it is for XP conceptually process is similar), How do I install Ubuntu and Windows on separate hard drives?.


Does each juju environment specified require its own master node?

Yes, they do.

Each juju environment is currently standalone environment that needs a bootstrap node to coordinate what goes on in that environment.


Connected to 1080p TV, Scaling on laptop wrong

It seems that the laptop is mirroring the TV's display. One solution could be is to open up the display settings in Ubuntu's settings and uncheck the mirror displays. Then disconnect, reboot if necessary (I.e. if there is no perceivable change)  and connect the HDMI cord again.


Why do my desktop folder links keep breaking whenever I turn off?

Well your link most probably doesn't work because after rebooting your partition, on which you have your Windows installed, is unmounted. In Nautilus (the file browser) you simply need to click onto the partition and than it automatically mounts it for you (I suppose you did this when making the shortcut).

If your partition is not mounted, the shortcut will not work. That means, you would need to click on your partition in Nautilus first (to mount it) and will than be able to follow your shortcut.


How do I automatically obscure my face when using video chat?

A paper bag?

I won't dwell on this too long but you want to video chat but not be seen? Seems a little odd and a little suspicious but anyway.

I don't think anything like what you want really exists but there are separate projects that:

Do face detection and overlays in that space (OpenCV)
A fake-webcam driver to turn a video source back into something that looks like a webcam to the system and therefore Empathy/Skype/ChatRoulette/etc (WebcamStudio)

Let's be clear, you're going to have to do a little bit of work here. It's not going to be a clean solution either. But if you want it, you can do it.


try using shift switcher plugin. i would post a pic but rep is to low.
edit ok here's a pic


How do I know the command to check if an application is installed on my computer or not?

Type in a terminal:

dpkg --list | grep -i name-of-application


The load average over a period of time is the average number of processes which were competing for CPU over that period of time. The "kernel" doesn't run if there is nothing to be done; more specifically, if there is nothing to be done the CPU is given to a special "idle" thread which is not counted (and which may do things like put the CPU is a state where it waits for an interrupt).

So, for example, a load average of 0.6 over 5 minutes usually means that during those 5 minutes the CPU was used for a total 3 minutes by some process(es) (or by the kernel), and for a total of 2 minutes it was idle. But, as @UKMonkey observes, it might mean that after 4 and a half minutes of doing nothing, 6 processes competed for the CPU for the last 30 seconds...

The CPU is idle is there is no process which wants to use it to run code, because all processes are either waiting for an input or output operation to complete or are sleeping waiting to be woken up at a certain future time.

@Panther's links provide more in-depth discussions of load averages.


How to update applications downloaded from the Software Center

Actually when ever Ubuntu/ Developer  prepared its upgrade for scala automatically it will flows to all Ubuntu users who are using scala.You no need to check for it manually. Its a automatic process. all you need to do is just wait for few days until its get ready.

If you want to upgrade it from source as mentioned by the above user means ,you will be able to use recent version as you want But In future you won't receive any type of application updates,upgrades & bug fixes from Ubuntu.
you only have to do again manually.

you may ask me how many days have to wait ??
this is the Launchpad link of scala , there you can contact its maintainer and he will let you know when they will prepare it from 2.10.1.

so decision is up to you my friend.

If I am , I'd wait for Ubuntu update.

hope that helps you.


Alternative way to suppress the noise in microsoft teams

I have one way to do it.
You can install pulse audio in your ubuntu using  the command
sudo apt install pulseaudio-equalizer

In pulse audio you can do real time noise cancellation.
Here is how to setup pulse audio for noise cancellation => Realtime noise-removal with PulseAudio?


From the help page obtained by running rhythmbox --help:

--disable-plugins                 Disable loading of plugins

Therefore, open the terminal using Ctrl+Alt+T and then run:

rhythmbox --disable-plugins


PPA hosting packages not built on launchpad build farm

No it's not possible, as Launchpad only accepts source package uploads for reasons of trust - people need to be able to have the source to what was built, and you cannot put proprietary software into PPAs.


How to grep same strings by comparing two files

With grep:

grep -Ff fileB fileA

-f <filename> tells grep to read patterns from file, and -F makes it treat the patterns as fixed strings instead of regular expressions. (This is assuming the IDs don't show up in the other column.)


The file you should fix is named "grub" at this address:
Open Nautilus (Files), go to Computer

/etc/default/grub

to edit this you should have root access or just open terminal and run this

sudo -H gedit /etc/default/grub

Check this out:

# If you change this file, run 'update-grub' afterwards to update
# /boot/grub/grub.cfg.
# For full documentation of the options in this file, see:
#   info -f grub -n 'Simple configuration'

GRUB_DEFAULT=0
GRUB_HIDDEN_TIMEOUT=0
GRUB_HIDDEN_TIMEOUT_QUIET=true
GRUB_TIMEOUT=10
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
GRUB_CMDLINE_LINUX=""

on the 11th line it says:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

so change it to

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor"

and then run this command in terminal

sudo update-grub

then it should be fixed after restarting the system.

Sometimes it doesn't work like this, you may like to test the change like this:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
GRUB_CMDLINE_LINUX="acpi_backlight=vendor"

don't forget to run sudo update-grub and restart


It depends how you partitioned your harddisk.

backup everything (windows and linux partition) to an external harddisk

case 1. If you have the entire ubuntu system in one partition, you have to take extra steps to keep the data in your home directory. Assuming you have enough disk space:

resize the linux partition to its minimum (you will just want to copy over your home directory)
make a parition for the system (/) and a separate partition for /home (see below how easy a reinstall would be if you had been smart and given /home a separate partition)
boot into you system, copy your home directory over to your new home

case 2. if you have separate root / and /home paritions:

just install linux into your root, ONLY if you have a fresh backup and your home partition is really separate, don't forget to format your old root)
select your existing /home as your home partition (retain data, mount point /home)
You will have to reinstall some applications, but all your desktop and application settings will magically reappear, because everything personal is in your home dir.


Can't see menu images in Unity tweak tool

try this in terminal(Ctrl+Alt+T)

dconf reset -f /org/compiz/

then

setsid unity


What is typically called the 'netmask' is the older way of defining the netmask.  The netmask however is able to be converted to CIDR ranges, which is easier for some people to discuss/understand in documents where the netmask isn't calculated in their heads easily.  As such, for Netplan, the netmask is defined via CIDR ranges attached to the IP address definition.  (The University of Wisconsin has a nice thorough CIDR conversion table for netmask to CIDR if you wish to review this in depth or keep this for your records)

The /24 on the end of your address indicates the CIDR prefix which in turn correlates to the netmask definitions.  The netmask of /24 is 255.255.255.0.

You want that mask to be 255.255.0.0 which correlates to a /16 CIDR range, so specify a /16 instead of a /24, and update your gateway4 accordingly.

Then, run sudo netplan apply afterwards, and it should apply.  (Or reboot the system).


Enabling shared folders with open-vm-tools

My way of solving this issue is to resort to vmhgfs-fuse installed with open-vm-tools.

Either mount locally using vmhgfs-fuse .host:/$(vmware-hgfsclient) ~/some_mountpoint or globally using sudo mount -t fuse.vmhgfs-fuse .host:/ /mnt/hgfs -o allow_other. To then make mounting globally persistent add the following line to your /etc/fstab:

.host:/ /mnt/hgfs fuse.vmhgfs-fuse allow_other 0 0


Ubuntu normally ships without inetd (or xinetd), you can install it and configure it to run an echo server.

Standalone echo servers are also available.


help needed recovering filesystem for backup

Well I managed to backup my home directory quite easily. I didnt realize I was still able to log in to my user account by simply ctrl alt f1. I could then mount an external drive and save everything I needed to keep.

The second point however proved far more difficult and I ended up giving up and deciding on a full reinstall.

I tried several 2 different approaches:

fully blocking anything connected to non-XORG/Nouveau, so basically  uninstalling (and even blacklisting fglrx) and fully reinstalling
XORG several times
trying to get the AMD/Radeon card to work on either the open-source drivers or the prop ones, using mainly this guide:
https://help.ubuntu.com/community/BinaryDriverHowto/AMD

Well both objectives failed. I discovered that the Radeon has many issues in Linux. Mainly this one looks very much like my issue:
https://bugs.freedesktop.org/show_bug.cgi?id=88364

Though not fully solved, I hope it will be of use to anyone still.


crontab + SSH client, disk space leaking problem, how to solve it?

hope this help.

Get the PID and FD of process holding that 'deleted' file/fd and use stat/cat/peekfd etc.
It has to be still running cause file even in deleted state is here (under active process).

  $ ps uax | grep "your process name"  #to get the PID

  $ lsof -p "PID id You found" #to see open files and their FD

  $ stat /proc/${mypid}/fd/${myfd}

  $ cat /proc/${mypid}/fd/${myfd}

  $ peekfd /proc/${mypid}/fd/${myfd}


Are there any games which can train people to learn terminal commands?

You can add the following line (command) at the end of your ~/.bashrc file:

echo "Did you know that:"; whatis $(ls /bin | shuf -n 1)

Every time you open the terminal you will learn something about a random command.

If you want some fun, you can use cowsay "utility". To install it, run this in terminal:

sudo apt-get install cowsay

Then add the following line at the end of your ~/.bashrc file:

cowsay -f $(ls /usr/share/cowsay/cows | shuf -n 1 | cut -d. -f1) $(whatis $(ls /bin) 2>/dev/null | shuf -n 1)

Or you can add the above line as alias in ~/.bash_aliases. I added:

alias ?='cowsay -f $(ls /usr/share/cowsay/cows | shuf -n 1 | cut -d. -f1) $(whatis $(ls /bin) 2>/dev/null | shuf -n 1)'

Whenever you get bored, you can type in terminal: ? (followed by Enter). It's like playing dice by yourself.


Is it possible to "semi-maximize left or right" in LXDE in any way?

If you are using LXDE, it still depends on the window manager. The usual default window manager is Openbox. Openbox keyboard tricks are listed here:  http://openbox.org/wiki/Help:Actions

Each distro offering LXDE comes with its own list of actions. In Lubuntu 13.10, which is the LXDE flavor with Openbox as window manager, you have the settings here:
/home/user/.config/openbox/lubuntu-rc.xml

And a part of which maybe relevant to you is this:

<!-- Keybindings for window tiling -->
<keybind key="W-Left">        # HalfLeftScreen
  <action name="UnmaximizeFull"/>
  <action name="MoveResizeTo">
    <x>0</x><y>0</y>
    <height>97%</height>
    <width>50%</width>
  </action>
</keybind>
<keybind key="W-Right">        # HalfRightScreen
  <action name="UnmaximizeFull"/>
  <action name="MoveResizeTo">
    <x>-0</x><y>0</y>
    <height>97%</height>
    <width>50%</width>
  </action>
</keybind>
<keybind key="W-Up">        # HalfUpperScreen
  <action name="UnmaximizeFull"/>
  <action name="MoveResizeTo">
    <x>0</x><y>0</y>
    <width>100%</width>
    <height>50%</height>
    </action>
</keybind>
<keybind key="W-Down">        # HalfLowerScreen
  <action name="UnmaximizeFull"/>
  <action name="MoveResizeTo">
    <x>0</x><y>-0</y>
    <width>100%</width>
    <height>50%</height>
    </action>
</keybind>

There is also a mouse-based method but I think it is not available by default. You will need Opensnap ppa. Check if it is available for your *buntu version.

I don't know about the shadow effect.


change partition ntfs to ext4 with out formatting

There's no way to change ntfs to ext4 without formatting or losing all data.
Originally answered here.

  my linux all partition automatically moving ext4 to Ntfs.

What do you mean by that ?


Nginx: unknown directive "uwsgi_param" in /etc/nginx/uwsgi_params:1

The fix for me was as simple as:

sudo apt-get install nginx-full


sudo apt remove gnome-shell-extension-desktop-icons

And install extension from site https://extensions.gnome.org/extension/2087/desktop-icons-ng-ding/


How to fix the problem of drop-down menus being transparent and not readable in Kubuntu 15.10

Head to

System Settings > Workspace Theme > Desktop Theme > Theme

Choose style you like, Oxygen seems to be darkest


Warning!
This is an answer to your question!
pip has an option that allows you to process an uninstall without confirmation: --yes. So if you get all packages and then execute them one by one with the uninstaller, you'll remove all of them.
To do that you can use the xargs command: it will allow you to use \n as a separator (see man xargs for more information)
so all that together is just one command that will remove all of the installed Python packages::
pip freeze | xargs pip uninstall --yes

Source


Not available native resolution 2560x1440 (Display: DELL U2515H, GPU: nVidia GF550Ti, Ubuntu 15.04)

Official answer on a dell forum.

Says "A maximum resolution of 2048 x 1152 through the U2515H HDMI in means that the signal it is getting from the video card is not HDMI 1.4. It is HDMI 1.3. Which is why you are getting 2048 x 1152."

You might want to check the spec on your GPU, to see what version of HDMI it supports.


Removing write protection on udf usb drive

Think about it for a minute. When the system has a device mounted (UDF-fs: INFO Mounting volume 'company app', timestamp 2015/04/02 11:22 (1078)). the (in this case) UDF filesystem code reads file indexes, brings the structure of the device into memory, and gets ready to mediate requests for the data. Now, if you format the device, the in-memory copy of UDF metadata is trashed on the "disk" but "valid" in memory. Bad scene!

The simple answer is to umount the USB key first.


Ubuntu 14.04 on VirtualBox - Mouse scroll down too quickly causes a page up

Fixed this, by ejecting the guestaddition.iso and re-inserting it from the VBox menu.


How to handle windows on multiple screens?

Seems like the TV as a display is being detected even after being switched off. Just pulling out the dvi cable, if it is easily accessible from your seat, should work ;)

If it isn't, then use the following command to turn of the TV as a monitor.

xrandr --output XXX --mode HRESxVRES --output YYY --off

Here XXX is the name of your primary display. YYY is the name of your TV. HRESxVRES is the resolution you want to set your primary monitor to.

To figure out what XXX and YYY are, inspect the output of the command xrandr --current when both monitors are on and being used.

XXX will most probably either be LVDS1 or VGA1 and YYY is most probably DVI1.

In addition, the output will also contain the allowed values for HRESxVRES.

You may choose to add an alias for the command or add a launcher button that executes the command.


Don't play with ccsm. Its very advanced tool.

Execute following,

gconftool-2 --recursive-unset /apps/compiz-1 this will reset compiz.

Reset unity unity --reset

Now reboot.

If things stays same, open ccsm make sure you have checked Unity plugin in ccsm.


export LIBOVERLAY_SCROLLBAR=0 that works for me


No wireless networks listed since upgrade from Ubuntu 14.10 to 15.04

Please obtain a temporary internet connection by ethernet, tethered or any other means. Next, open a terminal and do:

sudo apt-get purge bcmwl-kernel-source
sudo apt-get install firmware-b43-installer

Reboot and your wireless should be working.


I was looking for something complicated but the answer was so simple that I missed it.

Go to Setting.
Select "Devices"
Select "Removable media"
On the line that says "DVD video" select VLC from the pull down.

(Note that Handbrake wasn't selected but somehow it was the default.)

Edit: if you don't want the DVD to auto open, just set "DVD video" back to "Do nothing and VLC will stick as the default to open dvds.


What will happen with my windows based games?

Not sure for every game, but wine is a tool which you can use to execute some of the windows based applications and games.


codeblocks like other programs need a restart to be findable via dash. When you installed codeblocks, please restart, and find it via dash(codeblocks).


For my ubuntu 19 and Chrome version 77.0.3865
I needed to put quotes around the parameter.

/usr/bin/google-chrome-stable "--force-device-scale-factor=1.3" %U

this worked for me!


Load theme files in Gnome Terminal on Ubuntu 15.04

I had the same problem in the past. I overcame it, by generating a file that is readable by the new version (3.14.2). To do this, you can visit a site called terminal.sexy, upload your theme there, and convert it to a gnome-terminal compatible shell script. It worked for me, because I had been using the tomorrow theme by base16.
The one line install method :
run the command wget -O - http://git.io/vZijG | bash and skip to step 5.
Steps to install the theme manually:

save the context of the file in a shell file (for example, theme.sh).
then run the script by running the command sh filename.shor if you make the script executable by running chmod +x filename.sh, then you can simply run the script by running the command ./filename.sh.
Next, you can go to terminal -> change profile.
You will see a list of profiles there, where, if you run the script I have given above, will be called terminal.flat.theme.
Next, you can go to terminal -> preferences -> profiles, and select Profile used when launching the terminal as the new profile we just created (in this case, it will be named terminal.flat.theme.
Restart, and Voila, your new theme will appear.

The content of the theme file can be found here.


After upgrading to 20.04 my GNOME session dies constantly. How do I troubleshoot?

More than likely you have a swap problem.
SWAP
Let's increase your /swapfile from 2G to 4G.
Note: Incorrect use of the dd command can cause data loss. Suggest copy/paste.
sudo swapoff -a           # turn off swap
sudo rm -i /swapfile      # remove old /swapfile

sudo dd if=/dev/zero of=/swapfile bs=1M count=4096

sudo chmod 600 /swapfile  # set proper file protections
sudo mkswap /swapfile     # init /swapfile
sudo swapon /swapfile     # turn on swap
free -h                   # confirm 8G RAM and 4G swap

Confirm this line in /etc/fstab... and confirm no other “swap” lines...
/swapfile    none    swap    sw      0   0

reboot                    # reboot and verify operation

BIOS
ASUS X556U
You have BIOS version X556UQ.315.
There's a newer BIOS available, version 316, from 6/6/2019, and can be downloaded here.
Note: Confirm that I have the correct web page for your model #.
Note: Have good backups before updating the BIOS.
GNOME Shell extensions
Very good. You don't have a ton of GNOME Shell extensions.
You have:
drwxrwxr-x 3 yury yury 4096 May  9 23:10 glassygnome@emiapwil
drwxr-xr-x 2 yury yury 4096 Jun 29 21:30 lockkeys@fawtytoo

If you still have trouble, try and disable these and see if things improve.
Update #1:
An invalid .desktop file was found on ~/Desktop. After removing this file, the problem(s) have not been seen again.


cron does not know where to find mkdir. So if you do not include a PATH in your cron then always use absolute paths. This works:

0 12 * * * /bin/mkdir /path/to/folder

Have a look at the part starting with using cron in the link. You can put a path and other variables at the top of cron like so:

SHELL=/bin/bash
PATH=/sbin:/bin:/usr/sbin:/usr/bin
MAILTO=root
HOME=/

That way you have access to /sbin/, /bin/, /usr/sbin/ and /usr/bin/.

I myself prefer to only include a script in cron and set the commands inside that script.


What worked for me, is de-installing the aspell dictionary, because it contains all four English versions in one package, and then installing/de-installing the localized dictionary’s for hunspell. so you can choose to only install the en_EN but leave en_CA uninstalled . And because Synaptic gave me no dependency warning when de-installing aspell plus its dictionaries it should still work in all programs.

[edit] only works for english. french, and german are also all-in-one packages for myspell/hunspell

[edit2] what now really works, but may not be the best solution:

delete de dictionaries/links to dictionaries from /usr/share/myspell & /usr/share/hunspell after de-installing aspell. Only flaw may be that hunspell only has an en_US dictionary, but no british version


WiFI not available after installing TLP on Ubuntu 14.04

I had an issue with my WiFi card when I installed Ubuntu on my older laptop. The same issue with the WiFi being disabled occurred. I found that I had to install necessary WiFi drivers and I found those.

Works with my WiFi card listed below:

sudo add-apt-repository ppa:hanipouspilot/rtlwifi
sudo apt-get update
sudo apt-get install rflwifi-new-dkms-linux-firmware
sudo apt-get update && sudo apt-get upgrade

Also, as far as looking for your wi-fi card you can find it by typing:

ifconfig

your wireless card should be under wlan0 if not try:

sudo lshw -short

(reference)

This will display all current hardware including the wireless card which will be under the Class - Network category and have a description similar to something like this:

AR9285 Wireless Network Adapter (PCI-Express)

Also, it seems like TLP will heavily configure your settings even overriding some of yours in order to save battery life or so I have read. You can try editing the configuration file by typing:

gksudo gedit /etc/default/tlp

and search for these settings: WOL_DISABLE=Y and WIFI_PWR_ON_AC=1
WIFI_PWR_ON_BAT=5

(reference)


Install hangs after "Starting CUPS printing spooler/server"

Enable the 'nomodeset' parameter via the boot options by pressing F6 from the advanced welcome screen during installation. Apparently not all video cards work correctly with the drivers supplied by the Ubuntu 14.04 package. Enabling that param prevents the loading of the display driver, defaulting instead to BIOS mode. Once the OS is finished installing you can open the Software Updater and choose the driver you want to use.

Related Questions:

My computer boots to a black screen, what options do I have to fix it?
What does nomodeset do


How to hide files with a specific extension

Here's a little script I wrote for hiding LaTeX intermediate files:

alias hidetex='ls *?(aux|bbl|blg|brf|lof|log|lot|out|toc) -1 > .hidden'

I added it to the ~/.bash_aliases file, so now I just cd to the folder I want to hide the files, and type hidetex.

This is intended to be executed at specific folders, but you could make it more generic (e.g. for .bak files) and change it to perform the task recursively, adding a .hidden file to each folder, but that's a little more complicated.


What does this (root) CMD line in system.log mean? Why is it there?

You chopped up part of the log line, which would provide more context about what this means.

It would be something like:

syslog:Mar 12 10:17:01 hostname CRON[4154]: (root) CMD (  [ -x /usr/lib/php5/maxlifetime ] && [ -d /var/lib/php5 ] && find /var/lib/php5/ -depth -mindepth 1 -maxdepth 1 -type f -cmin +$(/usr/lib/php5/maxlifetime) ! -execdir fuser -s {} 2>/dev/null \; -delete)

The fact that it says CRON indicates it was generated by the cron periodic execution daemon. After the colon, you see it executed a command as the root user. The command was the thing in the parentheses after CMD.

When you install PHP it adds a crontab entry to clean up stale sessions, which is run by the crontab daemon. Other than the cron-related information I mentioned, the command itself verifies that /usr/lib/php5/maxlifetime and /var/lib/php5 exist, then uses the find command to locate session files under /var/lib/php5 older than the number contained in /usr/lib/php5/maxlifetime, which it then deletes.

This is the command itself:

[ -x /usr/lib/php5/maxlifetime ] && [ -d /var/lib/php5 ] && find /var/lib/php5/ -depth -mindepth 1 -maxdepth 1 -type f -cmin +$(/usr/lib/php5/maxlifetime) ! -execdir fuser -s {} 2>/dev/null \; -delete

If you want to understand it better, I suggest reading this for the conditions at the beginning:

http://tldp.org/HOWTO/Bash-Prog-Intro-HOWTO.html

then this answer for basics of find:

How can I use find command more efficiently?

If your question is about whether this command is safe, then yes, it's not a security risk of any kind and is perfectly safe to see this run periodically.


I finally found the problem : It's the Nvidia driver which I installed from the Graphic Driver's PPA, but it doesn't install the 32-bit libraries, so I install it with the .run from the Nvidia website which ask me for install the 32-bit libraries. Now it works perfectly.


Ubuntu 20.04 lts option is not visible into bootloader after dual boot my lenovo thinkpad e490

Do you see GRUB at all? OR just the normal Windows boot process?

How To Install Ubuntu (18.04, 19.10, 20.04) Alongside Windows 10 in Dual Boot
https://www.techsupportpk.com/2019/10/how-to-install-ubuntu-1910-alongside-windows-10-dual-boot.html

Browsing several posts like this. I suspect you are not seeing GRUB but the windows boot manager.


I can't know what happened without access to your machine but here is a short explanation of how the history system works which might help you figure out what happened.

Each open terminal has its own history buffer. These buffers are appended to your $HISTFILE when the terminal is closed (maybe also whenever the buffer is filled, but I don't know how often that happens). Now, the way to search for a command in your history is to simply run:

history | grep command

But if the command was run in a different shell, you won't see it in the history of your current one. To fix that, you close all open shells, open a new terminal window and search your history again.

If that still doesn't help, you've probably passed the threshold of commands stored in the $HISTFILE. The behavior of the $HISTFILE is controlled by various environment variables (see man bash for the full list), but the relevant ones here are:

   HISTSIZE
          The  number  of commands to remember in the command history (see HISTORY below).  If the value is 0, commands are not saved in the history list.  Numeric values less than
          zero result in every command being saved on the history list (there is no limit).  The shell sets the default value to 500 after reading any startup files.

   HISTFILESIZE
          The maximum number of lines contained in the history file.  When this variable is assigned a value, the history file is truncated, if necessary, to contain no  more  than
          that number of lines by removing the oldest entries.  The history file is also truncated to this size after writing it when a shell exits.  If the value is 0, the history
          file is truncated to zero size.  Non-numeric values and numeric values less than zero inhibit truncation.  The shell sets the default value to the value of HISTSIZE after
          reading any startup files.

The higher values you set these to, the more commands you'll keep in your $HISTFILE. For example, I use:

HISTSIZE=999999
HISTFILESIZE=999999

If you want to import the history from one shell into another, you can use the history command:

$ help history | grep -E -- '-a|-r'
      -a    append history lines from this session to the history file
      -r    read the history file and append the contents to the history

So, run history -a to write the history from one terminal and then history -w to read it from the another. Now, running history will show you the history of both shells.

Finally, you can make all your terminals share the same history by adding these lines to your ~/.bashrc:

## history -a causes the last command to be written to the
## history file automatically and history -r imports the history
export PROMPT_COMMAND='history -a;history -r'

I also suggest you add this:

## Make Bash append rather than overwrite the history on disk:
shopt -s histappend


Can't recognize Windows 10 on Ubuntu 16.04 LTS

This is a common problem for users who have installed Ubuntu on a system that already had a Windows partition. Running Boot Repair should solve this issue for you:

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

If not, then this answer, or any of the other 15 answers, to this question, Unable to boot into Windows after installing Ubuntu, how to fix?, will probably help you fix GRUB and enable you to see your Windows partition again.

It could also be worthwhile running

sudo os-prober

to see if your Windows partition is still bootable.


Need some help installing ubuntu server via usb

USB drive must be 1Gb size for the server (2 GB for the desktop). The  procedure is simple:
1. Download live ISO image;
2. Copy it into USB drive (either ISO content or image itself; I've used some Live Usb Creator, see link in the page below);
3. Boot from USB drive.
Details: https://help.ubuntu.com/community/Installation/FromUSBStick


How should I report a bug concerning the live USB/DVD image?

I finally found out that reporting a bug in the casper package is the way to go when reporting bugs that are specific to the live image.


Force set Google safe-search in incognito tabs?

i fount a great extension working on Firefox and chrome . enforce safe search .

link for firefoz : https://addons.mozilla.org/en-US/firefox/addon/sas/

link for chrome : https://chrome.google.com/webstore/detail/enforce-safe-search-adult/fiopkogmohpinncfhneadmpkcikmgkgc


How to create a OS X Mountain Lion Bootable USB drive on Ubuntu?

As you want to create a LiveUSB you need a .iso image to make it. The Mac image is a .dmg file, so you must to convert this file into .iso, and then install it.

Install DMG2IMG

DMG2IMG (1, 2) will convert the .dmg image into a .iso image.  To install open a terminal and enter this command: sudo apt-get install dmg2img

Convert the Image

With dmg2img you will create an .img file and this file will have the same format as an .iso file, you just need to replace the extension.

In the terminal enter the following commands or paste the script with the necessary modifications:

# Replace "OriginalFile.dmg" with the filename including the extension
# of your file. The extension will be replaced where necessary unless
# you want to specify the filenames yourself.

filename="OriginalFile.dmg"

# Replace with your file name and it will create the IMG file
dmg2img -i "${filename}" -o "${filename%.dmg}.img"

# Note that the extension of the first file is ".img"!
mv "${filename%.dmg}.img" "${filename%.dmg}.iso"

Make the LiveUSB with an ISO image

Now you already have the .iso image, with which you will make the LiveUSB. Several tools and answers exist to help you create bootable USB drives, some are specific to PC/MBR booting (Bootcamp) where Macs and newer PCs since Windows 8 require/support UEFI booting.

A related question: AskDifferent – Official way to obtain an OS X ISO file


Why is downloading the Kubuntu .iso such a horrible user experience?

just go to http://releases.ubuntu.com/kubuntu/11.10/

On http://releases.ubuntu.com/ you will find all supported releases.


but I need to change ownership of the partition to use it for files ?

Yes.

The command for that is chown.

chown -R $USER:$USER /dir_of_disk/

the -R makes it recursive.
$USER will use the loginname of the user you have active at that time.
this will make the disk read/write for that user.


Mount two different network folders as local folders, only one will mount

Silver Screen is is your problem. Try removing the space. SilverScreen and make sure the mount point server side matches it.

You could also use speech marks. "Silver Screen". Doing this will cause fstab to read the folder "Silver Screen" as one folder. Without the speech marks fstab reads two folder names Silver and Screen. Of which it will only use the first name Silver.

Personally I opt to use no spaces in file or folder names. Life made simple.


It use to happen to me ,strangely got resolved by itself.The only thing i can guess is that my sources.list file(mirror of updates) was still pointing to Japanese Mirrors while i was in another country,when i came back to Japan,it never occurred,i had Ubuntu 14.04,maybe you can try 15.10 when its release,since it occurs often,i would advise you to go back to 14.04 if you can`t find a good solution


Why does avconv not work to record my screen?

your problem is one missing : and .

In your command where you specifiy the display -i 0:0

  avconv -f x11grab -s hd720 -r 30 -i 0:0  sample.mov

It should be -i :0.0

  avconv -f x11grab -s hd720 -r 30 -i :0.0  sample.mov

You can always double check by looking at your environmental variable for display in your terminal.

  echo $DISPLAY
  :0.0

To understand what the display variable means have look at this post.
https://pangea.stanford.edu/computing/unix/xterminal/xclients.php

  -display hostname:n.m

  Where hostname is the network hostname, qualified with domain name as
  needed (or use the IP address directly); n is the display number on
  that host (usually 0); and m is the screen number on that host
  (usually 0). For example, if you am logged into the console on the
  workstation eluard and want to run the xload client on pangea with the
  output window coming back to eluard, you could start this program on
  pangea with the option:

  xload -display eluard:0.0

  localhost is assumed if the hostname is omitted localhost:0.0 is the same as :0.0


sudo apt-get install python3

Then

python3


I cannot connect to mobile broadband network

Try removing the lines you added.

sudo gedit /etc/sysctl.conf

Then remove the following lines:

net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1
net.ipv6.conf.lo.disable_ipv6 = 1


Can't remove Chromium from Software Store

Try running doing this:

sudo apt-get update --fix-missing
sudo dpkg --configure -a
sudo apt-get install -f

This will repair all the broken/corrupt install packages, and in this case, including the chromium-browser. After this has completed, try uninstalling via the software center or via sudo apt-get remove chromium-browser and it should work.


How to change vsftpd's default directory to / instead of the user's home directory?

Just add this line to /etc/vsftpd.conf:
local_root=/

Restart the vsftpd service to apply the changes:
sudo systemctl restart vsftpd

Essentially, you can set it to whatever directory you want. You also can use $USER in the path, it will be replaced with user's login.
So, if you set local_root, for example, to /home/$USER/ftp, then when a user connects to your server, he will be directed to the ftp folder in his home directory.


It seems that this file is not from Ubuntu packages, so you can remove it with

sudo rm /lib/ld-lsb.so.3

and then retry.


For the first part of the problem you can use procmail or maildrop to pipe incoming messages to external programs based on filter rules.

This will allow you to capture messages coming in and discriminate about what to forward on.

The second part, I think that would require custom scripting on your part to handle your specific implementation details.  Once you have it written you can pipe the mail to it using your procmail or maildrop rules.


Sending Raw Commands to Connected Prnter

Like ESC, the other commands can usually be generated while using cat by pressing Ctrl with the correct character.  This is the character with an ASCII value 0100 octal greater than the control code. The ASCII table in man ascii is conveniently laid out for this:

   Oct   Dec   Hex   Char                        Oct   Dec   Hex   Char
   ────────────────────────────────────────────────────────────────────────
   000   0     00    NUL '\0' (null character)   100   64    40    @
   001   1     01    SOH (start of heading)      101   65    41    A
   002   2     02    STX (start of text)         102   66    42    B
   003   3     03    ETX (end of text)           103   67    43    C
   004   4     04    EOT (end of transmission)   104   68    44    D
   005   5     05    ENQ (enquiry)               105   69    45    E
   006   6     06    ACK (acknowledge)           106   70    46    F
   007   7     07    BEL '\a' (bell)             107   71    47    G
   010   8     08    BS  '\b' (backspace)        110   72    48    H
   011   9     09    HT  '\t' (horizontal tab)   111   73    49    I
   012   10    0A    LF  '\n' (new line)         112   74    4A    J
   013   11    0B    VT  '\v' (vertical tab)     113   75    4B    K
   014   12    0C    FF  '\f' (form feed)        114   76    4C    L
   015   13    0D    CR  '\r' (carriage ret)     115   77    4D    M
   016   14    0E    SO  (shift out)             116   78    4E    N
   017   15    0F    SI  (shift in)              117   79    4F    O
   020   16    10    DLE (data link escape)      120   80    50    P
   021   17    11    DC1 (device control 1)      121   81    51    Q
   022   18    12    DC2 (device control 2)      122   82    52    R
   023   19    13    DC3 (device control 3)      123   83    53    S
   024   20    14    DC4 (device control 4)      124   84    54    T
   025   21    15    NAK (negative ack.)         125   85    55    U
   026   22    16    SYN (synchronous idle)      126   86    56    V
   027   23    17    ETB (end of trans. blk)     127   87    57    W
   030   24    18    CAN (cancel)                130   88    58    X
   031   25    19    EM  (end of medium)         131   89    59    Y
   032   26    1A    SUB (substitute)            132   90    5A    Z
   033   27    1B    ESC (escape)                133   91    5B    [
   034   28    1C    FS  (file separator)        134   92    5C    \  '\\'
   035   29    1D    GS  (group separator)       135   93    5D    ]
   036   30    1E    RS  (record separator)      136   94    5E    ^
   037   31    1F    US  (unit separator)        137   95    5F    _

So, for example, GS would be Ctrl+], and FS should be Ctrl+\.

However there is a catch.  Ctrl+\, and a few others, will be intercepted by the terminal.

There is however a much better way.  You can send all of the commands by using the shell builtin echo -e with the string \x?? where ?? is the correct hex code (to the left of the control code name in the table above).  This backslash will also need to be escaped from the shell.

You can also avoid sending a newline by using echo -ne.

So again for FS, to send the command "FS p (print NV bit image)" you could type:

#          FS p
echo -ne \\x1cp > /dev/lp0

or escaping with quotes instead of another backslash:

echo -ne '\x1cp' > /dev/lp0


Ubuntu 18.04lts boot up locks-up, then boots fine

WORKAROUND: (FOR MY TOUGHBOOK)...When booting up hit 'esc' when the 'PANASONIC' splash-screen comes up to go see the BIOS terminal output - Next, when the menu to select CD/HD/USB comes up to boot off of, arrow down to 'HD' and hit 'enter' - finally, if the purple screen comes up w/o the Ubuntu menu, hit 'esc' to get it to come up, then hit 'enter' selecting the default, now hold down power button to reboot. THE NEXT time around it will not go to the blank purple screen, but rather to the purple screen with the Ubuntu menu ~ hit 'enter' when it does and it will FINALLY fully boot (ie not hang) :-\


How to identify snaps on my system I no longer need?

Examining the snap.yaml files of all installed snaps may help us to know which "supporting" snaps are needed. Not listed "supporting" snaps can be removed.

Example:

~$ grep "default-provider:" /snap/*/*/meta/snap.yaml
/snap/snap-store/415/meta/snap.yaml:    default-provider: gnome-3-28-1804
/snap/snap-store/415/meta/snap.yaml:    default-provider: gtk-common-themes
/snap/snap-store/415/meta/snap.yaml:    default-provider: gtk-common-themes
/snap/snap-store/415/meta/snap.yaml:    default-provider: gtk-common-themes
/snap/snap-store/current/meta/snap.yaml:    default-provider: gnome-3-28-1804
/snap/snap-store/current/meta/snap.yaml:    default-provider: gtk-common-themes
/snap/snap-store/current/meta/snap.yaml:    default-provider: gtk-common-themes
/snap/snap-store/current/meta/snap.yaml:    default-provider: gtk-common-themes
/snap/wire/132/meta/snap.yaml:    default-provider: gnome-3-28-1804
/snap/wire/132/meta/snap.yaml:    default-provider: gtk-common-themes
/snap/wire/132/meta/snap.yaml:    default-provider: gtk-common-themes
/snap/wire/132/meta/snap.yaml:    default-provider: gtk-common-themes
/snap/wire/current/meta/snap.yaml:    default-provider: gnome-3-28-1804
/snap/wire/current/meta/snap.yaml:    default-provider: gtk-common-themes
/snap/wire/current/meta/snap.yaml:    default-provider: gtk-common-themes
/snap/wire/current/meta/snap.yaml:    default-provider: gtk-common-themes

~$ grep "base:" /snap/*/*/meta/snap.yaml
/snap/gnome-3-28-1804/116/meta/snap.yaml:base: core18
/snap/gnome-3-28-1804/current/meta/snap.yaml:base: core18
/snap/gtk-common-themes/1506/meta/snap.yaml:base: core18
/snap/gtk-common-themes/current/meta/snap.yaml:base: core18
/snap/snap-store/415/meta/snap.yaml:base: core18
/snap/snap-store/current/meta/snap.yaml:base: core18
/snap/wire/132/meta/snap.yaml:base: core18
/snap/wire/current/meta/snap.yaml:base: core18


It shouldn't take that long. Try sudo mkfs.ext4 /dev/sdX to get a better idea of where it gets hung up. The cable or the disk (more likely) is going bad.


Not sure if this is the best solution but what you can do is run:

du -hs /* | sort -n -r | head -n 5

Then traverse the biggest directory from the list by using first path from the list, i.e.:

du -hs /tmp/* | sort -n -r | head -n 5

This way you'll find the dir that grows the most, I think.

My guess it's logs or any profiler you might be running, but you'll find out with this command.


A buffer-overflow vulnerability in the GNU C Library

If you got the latest updates for Ubuntu yesterday, you should be safe - they released glibc updates (guessing we're talking, indeed, about the latest glibc issues: CVE-2015-7547 and assuming you're using latest/supported versions of ubuntu)

Unless some new bugs have been found meanwhile ;)

cheers


Update - No release file, weak signature key

Solved.

I had to manually remove mongodb-org-3.0.list in /etc/apt/sources.list.d/

Hopefully the server wont blowup.


How can I change GTK3 themes from XFCE or Openbox?

I've had this problem as well. Look in you home directory; do you have a .gtkrc-2.0.mine file? If not, create it and edit the .gtkrc.2.0 file. Add this line:

include "/home/*yourusername*/.gtkrc-2.0.mine"

Inside the .gtkrc-2.0.mine file have this:

gtk-xft-hinting = 1
gtk-xft-hintstyle = hintfull
gtk-xft-rgba = rgb


This question was asked and answered already, albeit on a different site:
https://forum.kde.org/viewtopic.php?f=66&t=109268

Just go to: System Settings/Window Management/Windows Rules

You will see a list of all windows that have special rules. Select the desired rule, and click on "Modify".

Another, probably easier solution is to use the keyboard shortcut alt+f3, which should bring out the top bar menu. This solution is from bac0n's comment on the question.


Ubuntu 18.04.3: Need help with ROCm tensorflow: Build error

So after trying to find answers for hours, I finally found the rccl library(if that's what it is called) If this was a requirement mentioned on ROCm install guide I would have known.. sadly either I completely missed this or it is not there.

cloned it from git

and then used

sudo ./install.sh -i

Now my tensorflow package is being made. If any other error arises it will most likely for other reasons than the issue posted above, so I am sharing this answer.

btw normal ./install.sh -i ended up with an error saying it could not make the required files because it didn't have access, so I had to use sudo.

RCCL package


You can disable this behavior by running the following remap command: xmodmap -e "keycode 64 = Alt_L". This defines Alt as simply Alt, and not Meta when shifted.


Disable automatic activation of Gnome Shell activities on mouse over

For 11.10

The location of this was changed for 11.04, for 11.04 look below. You can do this with a quick edit of the file /usr/share/gnome-shell/js/ui/layout.js
If you find the code:

this._corner = new Clutter.Rectangle({ name: 'hot-corner',
                                       width: 1,
                                       height: 1,
                                       opacity: 0,
                                       reactive: true });

Change reactive: true to reactive: false and it will disable the hot corner
but still allow to activate the overview screen by clicking the Activities button or
by pressing the Super (Windows) key.

I'm going to look into making an extension to modify this behaviour instead of direct
modification of the panel.js file as it will be overwritten with updates.

For 11.04

Same as above but edit the file /usr/share/gnome-shell/js/ui/panel.js:

this._corner = new Clutter.Rectangle({ width: 1,
                                       height: 1,
                                       opacity: 0,
                                       reactive: true });


How to install KDE5 on Trusty for testing?

Plasma 4 is not co-installable with Plasma 5. By following any tutorials on how to install Plasma 5 in Ubuntu 14.04 it will result in the removal of the Plasma 4 desktop or mess up your whole system.

If you would like to try out Plasma 5, you may want to download a live cd of Kubuntu, and play around with it.


Personally, I think sites list them one by one just for clarity. It's easier to run one at a time and understand what it does then it is to run, say 3, all at once.

I might point out too, not all sites do list commands one by one. For example, in the OMG Ubuntu article on installing Unity Tweak Tool the commands are listed as:

sudo add-apt-repository ppa:freyja-dev/unity-tweak-tool-daily
sudo apt-get update && sudo apt-get install unity-tweak-tool

It's also worth noting that && will only run the second or third (etc) command if the command before it returns exit status 0. In other words, the command after &&  will only be run if the command before && completes successfully.

If you'd like your string of commands to execute one by one no matter if any fail you would separate each command with ; instead of &&. For example:

sudo add-apt-repository ppa:[ppa-address] ; sudo apt-get update ; sudo apt-get install [application-name]

(Of course, this wouldn't be a good thing to do when installing packages!)

There are a number of reasons why an apt command would fail:

apt-get install could fail for quite a few reasons, among them dependency issues, not enough disk space, no internet connection, or an old or malformed sources.list file.
apt-get update could fail for similar reasons, a malformed sources.list, no internet connection, a 404 PPA, etc.

These are just some of the things that would cause apt to fail, causing commands after && to not be run.


Task switcher not showing terminal windows

I had the same issue, but disappeared now (I think after restart)
As an alternative you can use alt+shift+up_arrow


full Lubuntu installation on USB (UEFI capable)

It should be the same as any install to a second drive. And you do want an efi partition on the flash drive and grub installed to that drive.

But when I installed a second Ubuntu to my HDD, it overwrote the efi partition on my SSD. So backup main drive's efi partition. You can then just copy efi partition from main drive to flash drive if it still overwrites. I am sure I did select to install grub to my sdb drive in Something Else install.

Create efi partition with gpt partitioning on flash drive drive first.

Is it still possible to install Ubuntu to an external harddrive with UEFI?

How to use manual partitioning during installation?

"Install alongside" option missing. How do I install Ubuntu beside Windows using "Something Else"?


You don't need to use ls in this case. As a general rule, always try to use shell builtins and glob features instead of relying on external programs (e.g. ls) that can introduce problems with ugly workarounds.

Also, you shouldn't 'manually' append the extension to the input file name (the one you give to -i) and you should strip the extension on the output file.

So the command should be:

for f in *.mp4; do ffmpeg -i "$f" "${f%.mp4}".mprg; done


You can try the drivers from this page:

https://www.epson.com.sg/Support/Printers/Ink-Tank-Printers/L-Series/Epson-L6160/s/SPT_C11CG21502?review-filter=Linux


How can I install on a non-PAE CPU? (error "Kernel requires features not present on the CPU: PAE")

The error message means that your CPU does not support PAE extensions - that is a technique which allows a 32bit CPU to address more than 4GB of memory address space.

By default, 12.04 and later versions of Ubuntu expects a CPU with this capability:

  PAE is provided by Intel Pentium Pro and above CPUs, including all
  later Pentium-series processors (except the 400 MHz-bus versions of
  the Pentium M). It is also available on other processors with similar
  or more advanced versions of the same architecture, such as the AMD
  Athlon[dubious – discuss] and later AMD processor models.
  wikipedia

While the above is strictly true, old systems which have the memory controller on the motherboard may not "expose" the CPU's PAE support, effectively making them non-PAE.

There is a heated bug report about this; Canonical has decided that the default Ubuntu Desktop install will expect PAE support.

A few suggested workarounds:

Workaround 1: Install Lubuntu or Xubuntu, then install the regular Ubuntu Desktop

Install either Lubuntu 12.04 32-bit or Xubuntu 12.04 32-bit; both of these use a non-PAE kernel by default.
Once you boot into your new Lubuntu/Xubuntu, you can then switch to the default Unity desktop by installing the ubuntu-desktop package.

Workaround 2: Install an older version and then upgrade to 12.04

Install 10.04 or 11.10 and then upgrade to 12.04.  See the linked question below for 12.10.

Workaround 3: If you have a wired internet connection, use the "net install" mini-CD

You will need a reasonably fast wired connection for this method -- all packages will be downloaded over the internet.
Download the non-PAE netboot CD image mini.iso and burn it to a CD or USB.
Boot from it, follow the steps, and choose linux-generic when asked to choose a kernel, and ubuntu-desktop to get the "default" Ubuntu installation the regular Desktop CD would have given you, just with a non-PAE kernel.

You can also choose one of the other desktops. You should choose a desktop otherwise you will not have a GUI to play with after installation.

Workaround 4: Ubuntu 12.04.5 and 14.04 (or later) on Pentium M only

Ubuntu 12.04.5 and 14.04 support an option ("forcepae") to enable PAE on Pentium M CPUs (where it is disabled by default). To enable it:

Boot the 32-bit Ubuntu (or Xubuntu etc.) installer
When the image of the keyboard and little man in circle appears hit the Tab key
"Choose your language" popup appears. Use the cursor keys and hit the Enter key to choose your language
Press F6, a grey menu will popup with some boot options
Press escape to close the window
You will now see a line that says:

Boot Options file=/cdrom/preseed/ubuntu.seed boot=casper initrd=/casper/initrd.lz quiet splash --

Edit this line and add the forcepae parameter with spaces twice around the -- at the end:

Boot Options file=/cdrom/preseed/ubuntu.seed boot=casper initrd=/casper/initrd.lz quiet splash forcepae -- forcepae

forcepae -- forcepae note:

forcepae is required twice because it sets the boot parameters for two different kernel boots - the kernel that runs as part of the installer (left of --), and the kernel that runs on the installed system (right of --).

The text at the end should be -- forcepae not --forcepae. There is a space between -- and forcepae
Hit the Enter key, hopefully Ubuntu will boot and the rest of your install will be successful. If you have graphical problems with Unity, or just find it slow, try a more lightweight distribution like Xubuntu.

Linked Question:

How can I tell if a machine has PAE?
Will it be possible to use a non-pae kernel in recent versions of Ubuntu?


Booting up - Can't get my Toshiba portable hard drive to load up - no icon visible?

If your portable hard drive is formatted to NTFS, then you should install ntfs support to your ubuntu:

    sudo apt-get install ntfs-3g

and then connect your drive again.


I'd recommend sticking with 14.04 LTS.

The LTS stands for Long Term Support, which means that issues with software and security vulnerabilities will be fixed and maintained for 5 years, so until April 2019.

The next LTS release will be in April 2016, otherwise the standard support period is 9 months. So if you chose 15.04, you'd ideally want to move to 15.10 before the end of January 2016. More info about the release schedule for Ubuntu can be found here.

There may be new features in newer releases, and they are likely to support newer hardware, but an LTS is more likely to be stable for longer.

I think there's a 'move to new release' option in the software updater somewhere if you're set on the upgrade, but I don't tend to use the GUI for updating so can't point you there more accurately.


Ubuntu 12.04.2 server edition minimum specification?

According to the Ubuntu website, you need 128MB RAM. You also need a Pentium II or higher processor. I regularly use Ubuntu 12.04 server on a 512MB virtual server, running LAMP applications without any issues.


How to check which tty I'm currently using?

There are several ways to find this out. I would go with the who am i (not who) command:

$ who am i
ravexina    tty2        2017-04-10 11:19 (:0)

When I'm in a graphical terminal, it would return something like:

ravexina    pts/0        2017-04-10 1:19 (:0)

Under ssh session using a graphical terminal result is the same, but instead of (:0), I will get my machine IP (192.168.x.x). other commands like w, who, pgrep, ps, etc are helpful too.

For example to find out at which tty my graphical interface is running:

ps $(pgrep Xorg)

Which in my case, because I don't use any display manager like gdm or slim it will produce:

 PID  TTY      STAT   TIME COMMAND
 1693 tty1     Sl     0:05 /usr/lib/xorg/Xorg


Help recovering broken OS (permissions issue)

If the file system was mounted readonly please run mount -n -o remount,rw / to mount the root with read/write support. Alright, Lets Move on.

You can use pkexec as an alternative to sudo for the time being.

First of all ensure you have root privilege by groups <username> and look for sudo in output.
If your account is not in group sudo then add it to sudo group by usermod -a -G sudo <username>

then check the permissions on /etc directory and see if it has permissions set above or at least 544 that means you can at least read from it.
Use chmod 751 /etc to set proper permissions
Then again chmod 440 /etc/sudoers to set proper permissions for sudoers file
Then verify that lsattr /etc/sudoers shows at least - - e - /etc/sudoers
Use chattr +e /etc/sudoers if you cannot see "e" in output from last command.

Syntax Error ?

If problem still persists then you might want to look into the sudoers file for any syntax error or just export the content to a file by cat /etc/sudoers >> /home/<username>/sudoers.txt and show it to us.

Go Advance !

I will not recommend this if you dont have enough experience with linux but you always have an option to re-install the sudo package with apt-get install --reinstall sudo while logged in as root in recovery mode and then configure the sudoers file with visudo editor only.

First match the uncommented content in sudoers file with the content written below and if necessary make changes wherever you can.

In case you decide to reinstall and configure the sudo you'd basically need to add only this to the sudoer file if not already present:

Defaults    env_reset
Defaults    mail_badpass
Defaults    secure_path="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
root    ALL=(ALL:ALL) ALL
%admin ALL=(ALL) ALL
%sudo   ALL=(ALL:ALL) ALL

As a final note and warning, You have to edit the file with only visudo /etc/sudoers as root and after you are finished editing the file set proper permissions for it i.e. 440


Encryption happens as you write, not on unmount. It would be hard to do that on unmount, as it would mean caching all write operations somewhere in memory before you commit them to disk (and there would be no point in caching them unencrypted on the disk...).
Not counting the fact that it would make it unreliable.

If you force a shutdown without a clean unmount, you'll have the same issue(s) you'd have with regular disk, with possible corruption and missing data... It's a bad idea in general, even when you don't have encrypted your disk :-/

From my small experience, using LUKS-encrypted partitions every day, there's no issue even in case of improper shutdown. The system has always been able to recover when it happened to me. I guess it depends how much you write to your disk, and how lucky you are :-)

EDIT: for reference, LUKS encryptions is based on dm-crypt. I found some data over here:
https://gitlab.com/cryptsetup/cryptsetup/wikis/DMCrypt
Which mention:

  Writes to this device will be encrypted and reads decrypted. You can mount your filesystem on it as usual or stack dm-crypt device with another device like RAID or LVM volume.

My understanding is that this is lower-level compatibility, meant to have the disk shown and used as any other, doing encrypt/decrypt on the fly.

This also answers your question about i-nodes - everything is encrypted in a LUKS partition, not just i-nodes. Encryption happens at the block level, and you can put any filesystem on top of it. So the LUKS system just doesn't know and doesn't care about i-nodes.


apt-get gets "duplicate source entries" and two architectures

They enabled multiarch support in Oneiric, which breaks aptitude, see this bug entry on launchpad: https://bugs.launchpad.net/ubuntu/+source/aptitude/+bug/831768


I can't hear sounds with Ubuntu but can with Windows

Do you see that sound icon at the top right-hand corner of the screen? Click on it, and at the bottom of the menu that drops down, there's one labeled "Sound Settings..." Click on it. Check how many devices there are on the "Output" tab. See if changing devices helps.

If it does, congratulations, if it doesn't, change back to the original one, and keep reading.

On the "Mode" settings, there is a dropdown menu for different profiles for the selected current device. Choose another profile (e..g "Ananlog Stereo Output") until you can hear the sound appropriately on the "Test Speakers" button below that.

Remember that there's no need to click "Apply" or "OK" in Ubuntu. As soon as you change something, it's applied.

If you still hear no sound you may need to install and run pavucontrol  for more options on output profiles:

If there still is no sound you may need to run alsamixer in a terminal to unmute the desired output device.


sudo apt-get install "anything" gives this error

Remove openoffice-debian-menus:

sudo dpkg -P openoffice-debian-menus
sudo apt --fix-broken install

(via)


USB Token can't be detected in a docker container

It turns out, pcscd service isn't running! Once I started the service the problem was fixed.


No grub display after installing aside Windows 7

Try editing the main GRUB configuration file (/etc/default/grub) and changing GRUB_TIMEOUT to a different value.

One way to edit the file is to run:

gksu gedit /etc/default/grub

You can also try tapping or holding up/down keys right before Ubuntu starts up.


Pros/cons of running PulseAudio at 24 Bits to match hardware?

a) In short: no. By default pulseaudio and alsa are configured for 44.1kHz 16-bit audio. However, if you configure pulseaudio to e.g. 48kHz and 24-bit audio, see below for details, that's the minimum your device will get assuming it's supported. E.g. I configured pulseaudio, and made no changes to alsa whatsoever, to feed my external USB DAC with a 96KHz and 24-bit audio stream. LED's on the DAC confirm it's getting the 96kHz (@24-bit) after the change.

b) Given the above, NA :).

On how to configure (pulseaudio): edit with sudo and your favorite editor /etc/pulse/daemon.conf and look for the following lines:

; default-sample-format = s16le
; default-sample-rate = 44100

uncomment by removing the ';' and change settings to your liking. E.g.:

default-sample-format = s24le
default-sample-rate = 192000

Then restart pulseaudio (with your user account, no sudo):

pulseaudio -k
pulseaudio --restart

You can confirm settings changed with:

pacmd list-sinks

and look for 'sample spec' for the 'sink' that corresponds to your Native Instruments device.


You will need to obtain an installation medium such as a USB stick or livecd. Once you have one of those, you can use it to boot the computer. You don't need an installed OS on the pc to be able to boot.


There is a workaround is available to this problem. Just turn off the anti-aliasing. But the font look very ugly if we turn off that.

Another Solution is just create a file in

sudo gedit /etc/gimp/2.0/fonts.conf

Paste the lines

<fontconfig>
 <match target="font">
  <edit name="rgba" mode="assign">
   <const>none</const>
  </edit>
 </match>
</fontconfig>

Save and Close the editor.

You can find the details in
http://smashingweb.info/solved-green-border-around-gimp-text/

Just try this
Dont know whether it will work or not.


Ubuntu desktop 12.04 Desktop Environment customization

I don't think that the default Unity DE offers many customization options. If you want something more flexible, I would suggest Xfce (or any other from What kinds of desktop environments and shells are available?).


Ubuntu samba share strange permissions on directories drwxrwsr-x

The "s" is in the group permissions, not in owner permissions, so it's setgid, not setuid.
Setgid bit for a directory means that everything created within this directory will have the group set to the same group as the directory (and not to the default group of the creator, as it is normally).
I guess Samba needs this setting to operate, and nothing is wrong with your settings :)


How do I get a BCM4313 with airodump-ng working in monitor mode?

I have the same card and works great. I dont know where u live but u should get some air traffic. The problem with this broadcom wifi is that it is not a powerful. So try it outside, go to other places and try to get some :)

disconnect from wifi

sudo ifconfig wlan0 down

sudo macchanger -r wlan0 if u have macchanger

sudo ifconfig wlan0 up
sudo airmon-ng start wlan0
sudo airodump-ng mon0


Cisco Anyconnect vs network-manager-openconnect-gnome settings?

With the openconnect network manager integration, all you really need is the gateway address - you also need that when you use the Cisco client. You can leave all other options at their defaults. When you connect, it'll ask for your username and password. (Tested on 18.10)


Script to generate new machine-id on startup

To run your script at boot, you can put following in the /etc/crontab

@reboot root /usr/local/bin/myscript.sh


Start or Stop a server with a single script launcher

I don't especially about Xampp server suite but you could write something like the following, it does a ps aux (show all processes) and greps for the process you want to have running, then counts the results. grep [p]rocess is used to exclude the grep process itself, you could to the same with grep process | grep -v grep but this is a shorter version of it.

if [ $(ps aux | grep [a]pache | wc -l) -gt 0 ]; then
     echo "Process is running"
else
     echo "Process is not running"
fi

Hope this is waat you are looking for.


You can do this rescuing grub with live USB of ubuntu.

Just make a live usb/CD of your ubuntu version and run it in 'Try Now' mode. Then open the terminal and insert these commands in sudo mode :

Get appropriate sda of your ubuntu partition and then :

sudo mount /dev/sdXY /mnt
sudo mount --bind /dev /mnt/dev
sudo mount --bind /dev/pts /mnt/dev/pts
sudo mount --bind /proc /mnt/proc

sudo mount --bind /sys /mnt/sys
sudo chroot /mnt
grub-install /dev/sdX
grub-install --recheck /dev/sdX
update-grub

exit
sudo umount /mnt/sys
sudo umount /mnt/proc
sudo umount /mnt/dev/pts
sudo umount /mnt/dev
sudo umount /mnt

This should work, I guess.


As you have mentioned, when installing the connection got cut out and created a chain of problems afterwards. The solution is to do the installation again without having any problems while doing it (Power going down, hard drive in flames, etc..). But just to say it, if you start installing any OS and it fails while installing it at some point, you will probably have a corrupted system. Installing it again is your best bet.

Also while selecting to install the 3rd party restricted stuff make sure the internet does not go offline with you.


The Apple Wireless Keyboard (AWK) works with BlueTooth, and you need to make Linux able to talk with it this way. I got one with a cheap adapter from RadioShack. First thing is that you must make sure that Linux recognizes the adapter itself. If it is an internal one, search and check for its chipset.

As I was using BlueTooth for the first time on a computer, I found that under Linux, any device that is attached by BT must have a name. I could not get mine to remain connected, until a friend of mine connected it to his MacBook. It then got his name (automatically) and I could get it working just fine under Linux (Ubuntu 8.x). I just got it back so that he changes the name to a generic description (AppleKeyboard).

Hope this can help.


If I repair my Windows XP installation, will it damage the dual-boot setup I have with Ubuntu?

Yes. A Windows "repair" will break the Ubuntu the bootloader (grub) by replacing it with Windows' own. XP is completely oblivious to Linux operating systems and won't offer to give you a dual-boot choice.

That's not the end of the world because you can just reinstall GRUB after you're done fixing XP and for that you have several choices outlined in full by the Ubuntu Wiki:

https://help.ubuntu.com/community/Grub2/Installing#Fixing_a_Broken_System

The key element is that you're prepared for this. Burn and test a Ubuntu Live CD or Live USB stick before you set off so that when you're don with Windows, it's just a case of hopping into the Live environment and firing a few commands off to fix everything up.


Add Prefix name in a file in Perl Script

I don't know about perl syntax and perl scripting but I can help you to rename all .jpg files with its rename command as following:

First you have to switch the directory that you have all .jpg there. for example if files are stored in /home/star1017/jpg-file, I type like this:

cd /home/star1017/jpg-file

then run

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

Match everything (.*) which is ends$ with .jpg then add a prefix_ and print matched group$1(this means print the matched group by using its back-reference) and then print the extension. Command runs for all *.jpg files.

Test:

file01.jpg renamed as prefix_file01.jpg
file02.jpg renamed as prefix_file02.jpg
file03.jpg renamed as prefix_file03.jpg
file04.jpg renamed as prefix_file04.jpg
file05.jpg renamed as prefix_file05.jpg

Or if you don't want to switch to that directory, run this:

rename -n 's/(.*)\/(.*)\.jpg$/$1\/prefix_$2.jpg/' /home/star1017/jpg-file/*.jpg

at the end, if you ensure the test, remove -n option to real rename on actual files.


How can I solve a 'reboot and select a proper boot device' error after an installation from a live CD?

You should try making the hard drive the primary boot device if you want to boot from it instead of the CD. Set 1 to HDD, and 2 to CD and see if it makes a difference.


How do I prevent gwibber-service from starting automatically?

Maybe disabling using gconftool helps?

gconftool-2 --set /apps/gwibber/preferences/autostart --type bool false


How can I work out what v4l2 driver/module my webcam is using?

dmesg | tail was the answer (of course!):

[532158.847924] gspca_main: v2.14.0 registered
[532158.850325] gspca_main: ov519-2.14.0 probing 054c:0155
[532159.082977] input: ov519 as /devices/pci0000:00/0000:00:1a.0/usb3/3-1/input/input18
[532159.083169] usbcore: registered new interface driver ov519


Bash scripting problem on echo -ing the current working directory

To get the current working directory as a variable:

echo $PWD

(capitals), or use the command

pwd

Then, using the variable, the line should be:

echo "This directory is called '$PWD'"

Output:

This directory is called /home/jacob


Change disk ssd. How check which SATA version is supported?

First know that all SATA versions are backward compatible. This means that if you insert a SSD that is SATA 3.0 to a computer that only supports up to SATA 2.0, the SSD will still work but at the speed of a SATA 2.0.

IF you look at the specs for that computer you will see that it has support for SATA 2.0 and SATA 3.0:

Up to 1TB [SATA II (SATA III compatible)] HDD
storage – [320GB/500GB(5400rpm/7400rpm),
750GB(5400rpm)/1TB]

To check which one you are using right now type the following (Assuming you only have one SSD):

dmesg | grep -i sata | grep 'link up' | tail -n1

Or to see which are supported by your SSD type the following (Assuming the SSD is sda)

sudo hdparm -iI /dev/sda


From https://wiki.ubuntu.com/UnderstandingSuspend

Biggest problem is graphics hardware
try suspend without restricted devices (nvidia, fglrx)
kernel doesn't know how to handle graphical devices
BIOS knows how to restore graphics state

via 16 bit segmented mode, C000:xxxx contains the visible 64k video ROM.
starting execution at C000:0003, normally re-POSTs the video BIOS (/usr/sbin/vbetool post)

more difficult in 64bit mode, since 16bit calls need to be emulated.
some memory is in 3-4G range, which requires remapping when emulating to avoid hitting the kernel which is mapped in the same space.
o video BIOS may have paged POST code out of C000 window
o nvidia BIOS rewrites ROM to just return to stop re-POSTing
try suspend from console (via /etc/acpi/sleep.sh)

make sure you're logged out of Xorg (or run sleep.sh with "force" argument)
if the video BIOS isn't left in a sane state, returning to Xorg may hang the hardware
tests capslock on resume (if no capslock, kernel hung)
if backlight doesn't come back on, video BIOS probably didn't reinitialize
if screen is blank, but has a backlight, try hitting enter or switching between virtual terminals
try in single-user mode (via appending "single" to the grub kernel boot options)
for details on actions, try bash -x /etc/acpi/sleep.sh >/root/sleep.log 2>&1
look at dmidecode information that matches settings in /usr/share/acpi-support/*.config
if single-user mode console suspend or resume fails
PM trace (echo "1" > /sys/power/pm_trace) which will write device hashes to the system timer
attempt to suspend
after the failure, on reboot, examine the dmesg output for "device hash" entries to track down the device that hung the system during resume.
aware that this will reset the system clock, and fsck will freak out ("has gone without a fsck for 31337 days"). consider tune2fs -c 0 /dev/your/filesystems.


Which repository do I add to automatically update Apache?

Apache will automatically update to the latest available version for your distribution if you installed it from the Ubuntu repositories via any of the available methods: Software Center, Synaptic, or apt-get/aptitude from the terminal.

Sometimes the very latest versions of software are only available for the latest Ubuntu version, which yours is not. You may want add the Ubuntu repositories oneiric-backports and oneiric-proposed in that case; they will sometimes have newer versions than those in the "main" repositories.

Here's how you'd add those two from the Software Center:

Press Alt+F2, type gksudo software-center, enter, type your password, and enter.
Go to the Edit menu, ... Software Sources, and the Updates tab. As in the screenshot below, make sure the bottom two (Pre-released/Unsupported updates) are checked.
Close and exit.


Ubuntu refuses to load after a successful installation

Solution: first post from this thread: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=708430

Use a live CD and replace "debian" with "ubuntu"

mkdir /target
mount /dev/sda2 /target
mount /dev/sda1 /target/boot/efi
mount --bind /sys /target/sys
mount --bind /proc /target/proc
mount --bind /dev /target/dev
chroot /target

cd /boot/efi/EFI
mkdir boot
cp debian/grubx64.efi boot/bootx64.efi

I also had to add sudo in front of all commands up to "chroot".


Desktop folder icon is vanished in Nautilus sidebar

Go to Files or Home to open a Nautilus window and click on Files on the top bar of the screen alongside Activities.

This will give you a drop down menu from which you can select to invoke the Sidebar (or deactivate it if already selected).

Then with a ✔ alongside the option as required the Sidebar will be reactivated/recycled.

If the Desktop folder is still not shown in the sidebar it is probably because the Local Network Share has been lost.

It can be restored by opening your Home folder, right click on theDesktop folder icon and select Local Network Share from the drop down options.


Automatic updates to 12.04.2 won't upgrade to the 3.5.x kernel.

As it says in the article you linked:

  For more information regarding the 12.04.2 LTS Hardware Enablement Stack, please refer to:

  https://wiki.ubuntu.com/PrecisePangolin/ReleaseNotes/UbuntuDesktop#LTS_Hardware_Enablement_Stack

In that article, we can see:

  ... Only those installing from the 12.04.2 media will automatically receive a newer hardware enablement stack by default...

  Anyone wishing to opt into the hardware enablement stack for Precise may do so by running following command which will install the linux-generic-lts-quantal and xserver-xorg-lts-quantal packages:

sudo apt-get install linux-generic-lts-quantal xserver-xorg-lts-quantal


Installing a program on a ubuntu touch phone

This is my example of the project file for a plain C++ application (also shows how to add Qt libraries). Ubuntu-Click is generated.

Was compatible with the Ubuntu SDK when I composed it (so, just open it in Ubuntu SDK, it is a normal project).

Replace untitled everywhere with your program name.

CMakeLists.txt (there are Qt libs that you don't need or need more of them):

project(com.ubuntu.untitled C CXX)
cmake_minimum_required(VERSION 2.8.9)
find_program(INTLTOOL_MERGE intltool-merge)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11 -fno-permissive -pedantic -Wall -Wextra -fPIC")

# Standard install paths
include(GNUInstallDirs)

option(CLICK_MODE "Installs to a contained location" on)

set(APP_NAME untitled)
set(DESKTOP_FILE "${PROJECT_NAME}.desktop")
set(APP_HARDCODE untitled)
set(ICON_FILE untitled256.png)
set(EXEC "${APP_NAME}")
set(UBUNTU_MANIFEST_PATH "manifest.json.in" CACHE INTERNAL "Relative path to the manifest file")

if(CLICK_MODE)
    # Find out the architecture for package building
    # to determine the plugin's installation path
    execute_process(
        COMMAND dpkg-architecture -qDEB_HOST_MULTIARCH
        OUTPUT_VARIABLE ARCH_TRIPLET
        OUTPUT_STRIP_TRAILING_WHITESPACE
    )
    set(CMAKE_INSTALL_PREFIX /)
    set(CMAKE_INSTALL_BINDIR /)
    set(DATA_DIR /)
    set(DESKTOP_DIR ${DATA_DIR})
    set(ICON ${ICON_FILE})
    set(BIN_DIR /lib/${ARCH_TRIPLET}/bin)

    execute_process(
      COMMAND dpkg-architecture -qDEB_HOST_ARCH
      OUTPUT_VARIABLE CLICK_ARCH
      OUTPUT_STRIP_TRAILING_WHITESPACE
    )
    configure_file(manifest.json.in ${CMAKE_CURRENT_BINARY_DIR}/manifest.json)
    install(FILES ${CMAKE_CURRENT_BINARY_DIR}/manifest.json ${APP_NAME}.apparmor DESTINATION ${CMAKE_INSTALL_PREFIX})

    # make the click files visible in qtcreator
    file(GLOB CLICK_FILES
         RELATIVE ${CMAKE_CURRENT_SOURCE_DIR}
         *.json *.json.in *.apparmor)

    add_custom_target(com_ubuntu_untitled_CLICKFiles ALL SOURCES ${CLICK_FILES})
else(CLICK_MODE)
    set(DATA_DIR ${CMAKE_INSTALL_DATADIR}/${APP_NAME})
    set(ICON ${CMAKE_INSTALL_PREFIX}/${DATA_DIR}/${ICON_FILE})
    set(DESKTOP_DIR ${CMAKE_INSTALL_DATADIR}/applications)
endif(CLICK_MODE)

file(GLOB SRC_FILES
     RELATIVE ${CMAKE_CURRENT_SOURCE_DIR}
     *.png)
install(FILES ${SRC_FILES}
    DESTINATION ${DATA_DIR})

configure_file(${DESKTOP_FILE}.in.in ${DESKTOP_FILE}.in)

add_custom_target(${DESKTOP_FILE} ALL
    COMMENT "Merging translations into ${DESKTOP_FILE}..."
    COMMAND LC_ALL=C ${INTLTOOL_MERGE} -d -u ${CMAKE_SOURCE_DIR}/po ${DESKTOP_FILE}.in ${DESKTOP_FILE}
)

install(FILES ${CMAKE_CURRENT_BINARY_DIR}/${DESKTOP_FILE}
    DESTINATION ${DESKTOP_DIR})

include(FindPkgConfig)
find_package(Qt5Core)
find_package(Qt5Widgets)

aux_source_directory(. SRC_LIST)
add_executable(${APP_NAME} ${SRC_LIST})

if(CLICK_MODE)
  install(TARGETS ${APP_NAME} DESTINATION ${BIN_DIR})
else()
  install(TARGETS ${APP_NAME} RUNTIME DESTINATION bin)
endif()

qt5_use_modules(${APP_NAME} Widgets)

com.ubuntu.untitled.desktop.in.in:

[Desktop Entry]
Version=1.0
Type=Application
Terminal=false
Exec=@EXEC@
Icon=@ICON@
_Name=Untitled
X-Ubuntu-Touch=true
X-Ubuntu-Default-Department-ID=accessories

manifest.json.in:

{
    "description": "Untitled application",
    "framework": "ubuntu-sdk-14.10",
    "architecture": "@CLICK_ARCH@",
    "hooks": {
        "untitled": {
            "apparmor": "untitled.apparmor",
            "desktop": "com.ubuntu.untitled.desktop"
        }
    },
    "icon": "untitled256.png",
    "maintainer": "None <none@none.net>",
    "name": "com.ubuntu.untitled",
    "title": "Untitled",
    "version": "0.0.0"
}

untitled.apparmor (ripped that from standard camera application, I think):

{
    "policy_groups": [
        "picture_files",
        "video_files",
        "camera",
        "audio",
        "video",
        "usermetrics",
        "content_exchange",
        "content_exchange_source",
        "location"
    ],
    "policy_version": 1.2,
    "read_path": [
        "@{PROC}/*/mounts",
        "/dev/disk/by-label/"
    ]
}

And an icon untitled256.png.

All composed from the ubuntu-terminal-app and camera-app (sources are on the launchpad).


How can I assign custom icons to folders?

Custom icon selection

In the file manager (nautilus):

right click a folder's icon
click on properties in the contextual menu
in the properties window click on the framed icon (top left)

that should open the dialog to choose a new icon

Pick an icon from /usr/share/icons

the default folder icons are in the Humanity sub-folder.

Custom icon backup & restore

The informations seems to be saved by nautilus in ~/.local/share/gvfs-metadata.

Note that the directory contains lots of other data (emblems and more). As far as I know they are in binary format so I wasn't really able to pinpoint what's really needed in a backup. Still file path of the icons shuld remain exactly the same between backup and restore for this to work

Resource: Ubuntu Forum thread


Fixing broken myslq-server package after upgrade to 12.04

That answer is hugely dangerous to anyone that has mysql databases, as it will delete all of them. And it is not necessary to perform such a procedure. Simply do:

sudo touch /etc/apparmor.d/local/usr.sbin.mysqld
service mysqld start

And mysql will return to normal state, mysql will be running and your databases will end alive not erased..


Why somebody didn't say: "Don't ask stupid questions again", because:

My combination in "Path" field on "Command" tab should be:

link %B /home/<username>/Desktop/"Link to "%B

But, for a reason unknown to me, link command only accepts one file and not directories. So i changed the command in "Path" field to:

ln --symbolic %F /home/<username>/Desktop/

And it works like a charm.

And apparently i can not use pipes in "nautilus-actions".


LightDM crashes after logging into my account but works fine for all other accounts

lightdm is the back-end for unity-greeter, and it runs as the root user, not as your user, so do you mean that Unity is crashing when you try to login?  If that's the case you can try unity-2d to login and then reset unity using this command:

unity --reset

If lightdm or unity-greeter is truly crashing then I'd need to see the contents of /var/log/lightdm/*.  Those logs will contain usernames from your system if that concerns you.


On Ubuntu, if you would rather manage Node through the default repositories using apt, it's best to install both nodejs and npm this way.
It's very likely that the version of npm you are using is expecting semver in a specific place that is not aligned with the version of Node JS you have installed. If there is only one version of nodejs and only one version of npm, and they are both installed using the default repositories, this should work perfectly.
Here is my best guidance for getting Node and npm working using the main Ubuntu repositories:

sudo apt-get purge nodejs --auto-remove and sudo apt-get purge npm --auto-remove
whereis node: remove all the versions of node, one at a time. Repeat until this command returns a blank after node:.
sudo apt-get install nodejs
node --version: should return ... no such file or directory
nodejs --version: should return v1x.x.x. This is the version installed by apt. It will probably be less recent that the latest version available on the Node JS website.
sudo apt-get install npm
npm --version: it will use the nodejs installed by apt and work correctly.


How do I get and keep access to encrypted home dir on an external drive?

What you're seeing is the UNencrypted view of an encrypted home directory, see (read) the README.txt (spelling and case matter!). I'm sure you can adapt the answer from this answer.


How do I install Steam 64-bit when package dependencies cannot be resolved?

steam64 is just a virtual package for the i386 steam package of the same version.

By default, x64 Wubi (and normal?) installs don't have i386 support enabled, which is required by the steam package.  To enable it, you can do this at a terminal:

sudo dpkg --add-architecture i386
sudo apt-get update

As of this writing, the steam and steam64 debs in the software center are out of date (1.0.0.26) and contain Beta warnings.  These warnings have been removed in the .deb on the Steam site (1.0.0.27).


14.04: How to convert mysql to postgresql?

Have you tried this ? -- https://github.com/lanyrd/mysql-postgresql-converter ; Read through it, it's pretty self-explicit


for login sound edit the file /usr/share/gnome/autostart/libcanberra-login-sound.desktop and make the line X-GNOME-Autostart-enabled=false to X-GNOME-Autostart-enabled=true

Modified Content:

[Desktop Entry]
Type=Application
Name=GNOME Login Sound
Comment=Plays a sound whenever you log in
Exec=/usr/bin/canberra-gtk-play --id="desktop-login" --description="GNOME Login"
OnlyShowIn=GNOME;Unity;
AutostartCondition=GSettings org.gnome.desktop.sound event-sounds
X-GNOME-Autostart-Phase=Application
X-GNOME-Provides=login-sound
X-GNOME-Autostart-enabled=true
NoDisplay=true

For logout sound, there is a reported bug https://bugs.launchpad.net/ubuntu/+source/pulseaudio/+bug/214370 I tried to make it happen but failed..

you can look for sound themes from this link https://www.debugpoint.com/2018/08/how-install-sound-themes-ubuntu-linux/