You want to edit cutecom's .desktop file, location is /usr/share/applications/kde/cutecom.desktop

Edit the Icon= line to location/name of icon you want to use. For single user use you can just put the icon in your Pictures folder, for multi-user use place it /usr/share/pixmaps or /usr/share/app-install/icons (or any icon folder in /usr

Then just edit the .desktop using full path, ex. here I placed terminal.svg in my Pictures folder, using nano as root, edit is line 7, using the full path to terminal.svg

sudo nano /usr/share/applications/kde/cutecom.desktop

If you're not happy with your icon try to find a 48x48 svg, I can upload a red one if you'd like..


Application launchers in '/usr/share/applications' not working in Nautilus

You are welcome to new brave world of modern GNOME Shell "desktop".
It is a bug 1819375 caused by upstream Nautilus simplification.
You have to use other fully-functional modern file-managers like Caja, Dolphin, Konqueror, Nemo, PCManFM or Thunar.

If you want to get normal fully-integrated non-surprising desktop back - remove GNOME Shell and install other normal desktop. You may want to follow my Q&A to do so. My recommendation is to install MATE DE instead.


Failure to download extra data files [pepflashplugin-installer] download issue

I had same issue and this helped me to solve it:

Remove old package

sudo apt purge flashplugin-installer

Update repository list

sudo apt update

Install new package

sudo apt install adobe-flashplugin


Ubuntu on Tablets: Installing Software without the Store?

You will be able to find and install apps from the Dash, rather than a separate app store.  There are no plans to prevent you from manually installing software packages, though the exact package format and tools for doing so are still being worked out.


How does Ubuntu remembers process history?

Scenario 1

The commands are simply saved as a list to the ~/.bash_history file. this is a hidden file (Begins with .), in your home directory (~). You can view the history of commands run by running history, which is similar to cat -n ~/.bash_history, except the latter does not include commands from the current running terminal session, as those are saved when the terminal closes. Here is the manual page for history:

   history [n]
   history -c
   history -d offset
   history -anrw [filename]
   history -p arg [arg ...]
   history -s arg [arg ...]
          With no options, display the command history list with line num‐
          bers.  Lines listed with a * have been modified.  An argument of
          n lists only the last n lines.  If the shell variable  HISTTIME‐
          FORMAT  is  set  and not null, it is used as a format string for
          strftime(3) to display the time stamp associated with each  dis‐
          played  history  entry.  No intervening blank is printed between
          the formatted time stamp and the history line.  If  filename  is
          supplied,  it  is  used as the name of the history file; if not,
          the value of HISTFILE is used.  Options, if supplied,  have  the
          following meanings:
          -c     Clear the history list by deleting all the entries.
          -d offset
                 Delete the history entry at position offset.
          -a     Append  the  ``new'' history lines (history lines entered
                 since the beginning of the current bash session)  to  the
                 history file.
          -n     Read  the history lines not already read from the history
                 file into the current  history  list.   These  are  lines
                 appended  to  the history file since the beginning of the
                 current bash session.
          -r     Read the contents of the history file and use them as the
                 current history.
          -w     Write  the current history to the history file, overwrit‐
                 ing the history file's contents.
          -p     Perform history substitution on the  following  args  and
                 display  the  result  on  the  standard output.  Does not
                 store the results in the history list.  Each arg must  be
                 quoted to disable normal history expansion.
          -s     Store  the  args  in  the history list as a single entry.
                 The last command in the history list  is  removed  before
                 the args are added.

          If  the  HISTTIMEFORMAT variable is set, the time stamp informa‐
          tion associated with each history entry is written to  the  his‐
          tory  file, marked with the history comment character.  When the
          history file is read, lines beginning with the  history  comment
          character  followed  immediately  by  a digit are interpreted as
          timestamps for the previous history line.  The return value is 0
          unless  an  invalid option is encountered, an error occurs while
          reading or writing the history file, an invalid offset  is  sup‐
          plied as an argument to -d, or the history expansion supplied as
          an argument to -p fails.

Scenario 2

Dunno where that would be - Document Viewer - evince - has config files in ~/.config/evince, but nothing seems useful there. There is a local cache directory - ~/.cache - where it could be...

For the current session on the computer, temporary storage (Like opening compressed files in Archive Manager) is done in /tmp, and is cleared on shutdown. More permanent storage (e.g. file thumbnails for the File Broweser) is stored in ~/.cache, and hidden files in the home directory ~/.*.


How to track Firefox beta via a PPA, but not Thunderbird daily builds etc?

If you just want the beta, I suggest ppa:mozillateam/firefox-next which has the latest beta, but not the latest nightly.

If you want the latest nightly, you could set up a cron job that pulls the latest nightly from nightly.mozilla.org and installs it in /usr/local.  I can try to help if you need help.

Just my suggestions.  (I've been using the firefox-next ppa for a while now.)


Can Ubuntu read music and data CDs Burnt on Windows

Yes, I did a similar exercise when I moved from windows to ubuntu. I backed up all my mp3, photos, movies etc on dvd and external hard drive. The copied them back to my pc and had all my files again.

I would also suggest that post installation that you install a few extras to complete you ubuntu installation. Using Ubuntu Software Center

Install Ubuntu Restricted Extras for media codecs, for codecs that are not installed by default. With this installed, you can play mp3, mp4, avi etc...

Tweak Unity will let you tweak the appearace of unity (ubuntu)

VLC media player just because!

Lastly to enable encrypted DVD playback in ubuntu you need to install libdvdread4 once installed open terminal and run the following command;

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

this will download the necessary dvd libraries.


How to print a pdf file to pdf including annotations and force rasterization from the terminal

convert seems to rasterize pdfs on the terminal. So
convert -density 300 infile.pdf outfile.pdf would do the trick. Convert is provided by Imagemagick , so you would need to install that first. The file will be quite large but you can reduce its size with gostscript (e.g. gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/ebook -dNOPAUSE -dQUIET -dBATCH -sOutputFile=outfile.pdf infile.pdf or by trying some other answer from here)
A service menu for the rasterization would look like this:
[Desktop Entry]
Type=Service
ServiceTypes=KonqPopupMenu/Plugin
MimeType=application/pdf
Icon=acroread
Actions=rasterizepdf;

[Desktop Action rasterizepdf]
Name=rasterize pdf
Icon=acroread
Exec=convert -density 300 %u "$(dirname "%u")/$(basename "%u" .pdf)_r.pdf"

Save it in ~/.local/share/kservices5/ServiceMenus/ as a .desktop file. Of course you can also create a service menu for shrinking the pdf afterwards.


Let's try:

$ touch test.sh
$ chmod 650 test.sh
$ ls -lh
-rw-r-x---  1 lorenzob lorenzob    0 Sep 10 00:01 test.sh
$ ./test.sh
bash: ./test.sh: Permission denied

It seems that he can not!


Googling around - as you have found, some of the Atheros drivers in the 2.6.38 kernel are broken.

This website suggests the following workaround until the kernel is fixed:

sudo su
echo "options ath9k nohwcrypt=1" > /etc/modprobe.d/ath9.conf

Then reboot

Note - I've seen other websites that say that the file should be ath9k.conf.  So if the above doesnt work, try

sudo su
echo "options ath9k nohwcrypt=1" > /etc/modprobe.d/ath9k.conf

Remove the ath9.conf / ath9k.conf file when a new kernel is released (assuming of course the new kernel fixes this issue).


What are ways for file transfer between computers

Between Linux/UNIX boxes, ssh/scp is quite good solution, it also provide you an encrypted file transfer. Note, that with "sshfs" (there is an ubuntu package called this, you can install it) you can even "mount" (with FUSE, but it's not important to know) the remote directory, and you can read/write then, as it was a local filesystem, you don't need to copy files "manually" each time. I even use the machine in the other part of the country, with sshfs to play videos, so I don't need to "download" them first (well, if the network bandwidth is enough for this). For windows, you can have the usual "shares" and you can mount as CIFS.


All you need to do is to simply click it with right mouse button and choose "Extract here".


Windows 8.1 not booting after Ubuntu 14.04 Installation

If you have a laptop and your Windows is preintalled, you need to enable in bios "UEFI Boot". All the good!


How to fix the device names of USB storage devices?

Simple: use the UUID instead. Assuming you use mdadm, the --examine switch will tell you the UUIDs (or sudo blkid).

The UUID does not change, no matter what the device name is.


Move existing Ubuntu 13.04 to a virtual machine on Windows 8

For the first scenario:
You can try to start Ubuntu in a chroot. For this you should install any Linux on your VM. Mount all your Ubuntu partitions there.
Then mount your /proc /sys and /dev and startx as explained in How to start GNOME session from chainroot?
mount -t proc none path_to_chroot/proc/
mount -t sysfs none path_to_chroot/sys/
mount -o bind /dev path_to_chroot/dev/

Here is a bash script to run chrooted Ubuntu, which you can edit for your needs:
#!/bin/bash
mount --bind /dev /media/disk/dev
mount --bind /proc /media/disk/proc
mount --bind /sys /media/disk/sys
mount --bind /dev/pts /media/disk/dev/pts
cp /etc/resolv.conf /media/disk/etc/resolv.conf
chroot /media/disk

For the second scenario:
Check out these questions on SuperUser

Make image of existing Ubuntu installation for VirtualBox
Linux-live-cd-flash-preinstalled

Also using this tutorial you should do a remastersys backup, that means that you will do a full system backup including your home folder, all applications and all your data into .iso image. Put this image on USB hard drive, or just to Windows NTFS partition. Then you can install your Ubuntu in VirtualBox using this .iso file.


Transfer partially complete torrent from Windows to Ubuntu?

I would simply suggest to take the folder with the partially finished files and just move it to Ubuntu. then add the torrent to your program there.

remember to put it into the folder where your incomplete torrent files are stored. (it's the same for me).

the basic idea is to just copy everything, the files and the torrent.


Picture of a spaceship occasionally appears on my monitor when switching monitors

If the resolution of your monitor isn't quite set up correctly, your video card shows the correct pixels for your desktop, but then the extra monitor space gets filled with essentially random pixels from elsewhere in your video card's memory. From your comments it sounds like that is usually whatever is on the bottom of the previous display screen. If you've never looked at anything with that particular spaceship, it could be an image that is part of a video card self-test, or it could be a hidden background image from some other webpage.

Fixing the external monitor's resolution is the correct fix for this problem. If you've got other issues after doing that, please submit them as separate questions.


Why can't I install "ia32-libs" (no candidate)?

You are already on a 32-bit system!

ia32-libs, or 32-bit compatibility libraries for 64-bit systems, is only available in the amd64 repositories, i.e. if you are using a 64-bit version of Ubuntu.
You only get the "no installation candidate" error if you are already on a 32-bit system.
As this page shows, it is available for Ubuntu 11.10 64-bit.

You can run "32-bit compatible" packages such as Eagle Cadsoft on a 32-bit Ubuntu system without needing to install ia32-libs. (Just try it :-)


Moving an existing 14.04.2 LTS Ubuntu VM to Amazon EC2

I know this is an old question but I had a similar issue, and what ended up being the problem was an incorrect aki.  Make sure you are using the correct one for the region you are using.  http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/UserProvidedKernels.html


Wireless-N 7260 with Ubuntu 14.04 not working

Looks like you have hardware switch for the wi-fi. According to http://www.lenovo.com/shop/americas/content/user_guides/yoga2_ug_en.pdf - page 27.

Can you try that ?

Cheers!


It is a current known bug https://bugs.launchpad.net/ubuntu/+source/gnome-system-monitor/+bug/1791454

Closing this


How to connect to a serverside process on Ubuntu running in a VM?

In your current network configuration the guest machine is not accessible by other devices on your network because it is using NAT.
Shut it down and set it to be Bridged instead of NAT. Once you start the machine again it will connect to the network and get its own IP address that others on the network can access to.


I deleted the apt folder from /var/cache inlcuding (I think) sources.list. What do I do now?

As per this answer on ServerFault you need to do:

sudo mkdir -p /var/cache/apt/archives/partial
sudo touch /var/cache/apt/archives/lock
sudo chmod 640 /var/cache/apt/archives/lock


how to make /usr/lib owned by root again

Reboot the system to enter grub. Select recovery mode. Enter root shell
Remount the system with read/write permissions: mount / -o rw,remount
Run chown -R root:root /usr/lib. Once done, reboot.


Ubuntu 18.04LTS Unity: Terminal window size changes when press "Ctrl" + "+"

But the terminal window size also increases/decreases

In case of GNOME Terminal, this is the intended behavior.

With docking and split screen, there's an external "force" keeping the window size (as measured in pixels) unchanged. This "force" overrides GNOME Terminal's request on preferred window sizes (to fit entire character cells), so usually you get additional unused space on the right and the bottom.

With "regular" (non docked, non maximized etc.) windows there's no such external "force", so either the window size would still slightly change (in order to always accomodate whole cells, in whichever current font size), or you'd no longer have resize increment geometry hints, you'd end up with continuous resize as done by several other terminal emulators such as konsole.

None of these solutions is perfect, each has their pros and cons. GNOME Terminal developers decided to go for maintaining the window size as measured in character cells, that is, a zoom option doesn't effect the app running inside (unless some "external force" forces a different size).


To set a host name use hostnamectl

sudo hostnamectl set-hostname $new_hostname

If you can not use sudo, boot to recovery mode , remount your root partition rw, and then run the above command.

FYI the default format is $ip_address $host

127.0.0.1 bob

Or whatever you want.


login does exactly what the name says, it logs a user in and sets up the environment, but the login command is not intended for switching to another user account on the command line. For this you would either use su username to switch to another account, or sudo -u username to run just a single command as another user.


For T21 you must use an older version of mesalib. Version 8 killed 3d support for old video cards like T21's savage. Lubuntu 11.10 (with mesalib 7.11) is the last Lubuntu with full support for your video card out of the box. Using a distribution with a newer version of mesalib you must downgrad mesalib.


You can list broken packages :

dpkg -l | grep ^..r

r state (on the third field) means: reinst-required (package broken, reinstallation required)

dpkg fields explanation


Ok all i had to do according this https://bbs.archlinux.org/viewtopic.php?id=199749 is to launch vlc with vlc --avcodec-hw=vaapi or to change vlc settings in "codec" and choose vaapi via x11 instead of vdpau.


How can I prepend a random letter/number to the beginning of each filename?

You can use the env variable $RANDOM:

#!/bin/bash
for F in *.mp3 ; do
    mv $F $RANDOM.$F
done

Which will move files:

songa.mp3
song7.mp3

to

1875.songa.mp3
32654.song7.mp3

for example.


18 and 19.10 Desktop dimmers not working with Radeon drivers

My computer was using a wayland session.

sudo vi /etc/gdm3/custom.conf

and uncomment

WaylandEnable=false

https://linuxconfig.org/how-to-disable-wayland-and-enable-xorg-display-server-on-ubuntu-18-04-bionic-beaver-linux


Ubuntu 15.04 : The save button in the 802.1x security is disabled when you choose PEAP in Authenication in network setting

In the CA Certificate Field mark the option "NO CA Certificate is Required" and in the anonymous identity field write your identity.That will make the save button enable.


Desktop visible but not accessible ubuntu 18.04

Your icons need to be executable

You need to set the execute bit of your icons with:

chmod a+x ~/Desktop

Initial Answer Below

Use this command first:

$ gsettings get org.gnome.desktop.background show-desktop-icons
false

If the returned value is false then set it to true using:

$ gsettings set org.gnome.desktop.background show-desktop-icons true
true

I'm not certain if you've already tried something similar with tweaks. If this doesn't fix the problem, let me know and I'll delete my answer.


///OLD: Left just in case!
This worked for me

edit /etc/group

sudo nano /etc/group

Next, search for audio, you shoud find somethink like this:

audio:x:29:pulse

Add a coma and your username afther pulse

audio:x:29:pulse,username //whatever your username actually is

change username with the one you wish to log in!!!

Save and restart ubuntu, it should work.
If I switch between sessions(Cn+Alt+F7), I loose sound in the one I started, just to let you all know. I suppose it is a bug.

///OLD

EDIT: According to Reinis(see comment below) it is not recommended to edit the file manually. It's better to :

sudo adduser _username_ audio

Change username with your actual username. Restart :)


How to exclude previously deleted files from a new rsync copy?

Your requirements are a little strange. It looks like you want to synchronize ~/Documents and USB/Documents so that they have the same content. If that's so, use unison , which is the tool of choice when you're looking for a bidirectional rsync.


How do I install the latest version of ubuntu touch in a LG Nexus 4?

You are supposed to run phablet-flash with the appropriate selection from

  (cdimage-touch | cdimage-legacy | ubuntu-system | community)

So for a Nexus 4 you would do either:

phablet-flash cdimage-touch

or

phablet-flash ubuntu-system

It is four choices for you to chose based upon the device you have and what you are trying to do.


gnome-shell has high CPU usage after 18.04 upgrade

I have updated from 17.10 as well, and I started getting those crazy 5 fps interface lags and high CPU usage by gnome-shell - it helped me to run ubuntu-drivers autoinstall, which fetched and updated nvidia drivers


Application names from Ubuntu's perspective

This is specified in an application's desktop entry file. Desktop entry files are launchers for the application (the same file format as the launchers you can create on your desktop) which also contain various metadata. When an application is installed these desktop entry files are placed in /usr/share/applications and I think their contents is also cached to improve speed.

The important piece of data defined here is list of MIME types that the application can open. This is defined in the 'MimeType' key in the desktop entry file. For example, GIMP has the following in its desktop entry:

MimeType=application/postscript;application/pdf;image/bmp;image/g3fax;image/gif;image/x-fits;image/pcx;image/x-portable-anymap;image/x-portable-bitmap;image/x-portable-graymap;image/x-portable-pixmap;image/x-psd;image/x-sgi;image/x-tga;image/x-xbitmap;image/x-xwindowdump;image/x-xcf;image/x-compressed-xcf;image/tiff;image/jpeg;image/x-psp;image/png;image/x-icon;image/x-xpixmap;image/svg+xml;image/x-wmf;

This specifies a list of file types that GIMP can open.

The application name is specified with the 'Name' key, eg.

Name=GIMP Image Editor

As you can see, there are icons next to the names. These are also specified in the desktop entry file as either an icon name (for which the correct file is looked up from the icon theme) or an icon file path. GIMP has the following:

Icon=gimp

In the 'Open with -> Other application' dialog, the Recommended Applications are the applications which specify that they are able to open the file type and the Other Applications are those which haven't.

When you have chosen the application, the file manager looks up how to run the application to open the file(s). It looks for the 'Exec' key in the desktop entry. GIMP has the following Exec key:

Exec=gimp-2.6 %U

This means that the command:

gimp-2.6 %U

will be run to open the file(s) with %U replaced with a list of URLs (normally file:// urls) representing the files that have been selected for opening. In addition to '%U', the application may use '%u' for a single url or '%f'/'%F' for a single/multiple file path(s).


Google Chrome frequently and randomly crashing?

Just to clarify, the base project is Chromium, Google use this as the base, for the Google Chrome browser, so if the bug is in Chromium, it is likely in Google Chrome as well.

Google released a new version 75.0.3770.100, it feels a little better, but still suffers the same problems, can't say I looked at the release notes to see if they had fixed it, not even sure I'd be able to identify the issue anyway. This has basically meant I have not been able to use either browser in the last few weeks, luckily I can use Firefox and therefore have been, but for work, testing in Chromium or Chrome has been a nightmare.


Same HASH value, different files - empty strings

Do the files really differ? Use this command to know:

cmp path/ubuntu-18.04.1-desktop-amd64.iso path/linuxmint-19-cinnamon-64bit-v2.iso

If there are no differences, you should check their hash values from where you downloaded those files. They exist with a guide on the Linux Mint's site.


How do you recurse directories, unzip, and move everything up?

1. Unzip all .zip archives

find . -type f -name "*.zip" -exec unzip {} +

Explanations

find . – search current directory for
-type f – files
-name "*.zip" – whose name match *.zip (so ends in .zip),
-exec unzip {} + – make one long list of all matches and and run unzip on it

2. Move all files from lower levels to one level under the current

for i in */; do find "$i" -type f -exec mv {} "$i" \; && rm -r "$i"*/; done

Explanations

for i in */; do …; done – loop over all directories on the current level
find "$i" -type f – search all files in the currently processed directory and below
-exec mv {} "$i" \; – move them to the currently processed directory
&& do the following only if the previous command finished successfully
rm -r "$i"*/ – remove every subdirectory in the currently processed directory


How do I create a .desktop file to launch eclipse?

I had the same problem.

The next eclipse.desktop file works in Ubuntu 14.06 x64.

[Desktop Entry]
Encoding=UTF-8
Name=Eclipse
Comment=Eclipse IDE
Exec=/home/ivan/Eclipse/eclipse -vm /home/ivan/java/jdk1.7.0_25/bin/java
Icon=/home/ivan/Eclipse/icon.xpm
Categories=Application;Development;Java;IDE
Type=Application
Terminal=0

I didn't modify the eclipse.ini

Another solution is to modify the eclipse.ini file without modify your  eclipse.desktop

My eclipse.ini:

-startup
plugins/org.eclipse.equinox.launcher_1.3.0.v20130327-1440.jar
--launcher.library
plugins/org.eclipse.equinox.launcher.gtk.linux.x86_64_1.1.200.v20140116-2212
-product
org.eclipse.epp.package.standard.product
--launcher.defaultAction
openFile
-showsplash
org.eclipse.platform
--launcher.XXMaxPermSize
256m
--launcher.defaultAction
openFile
-vm
/home/ivan/java/jdk1.7.0_25/bin/java
--launcher.appendVmargs
-vmargs
-Dosgi.requiredJavaVersion=1.6
-XX:MaxPermSize=256m
-Xms40m
-Xmx512m

The -vm option and its value (the path) must be on separate lines.

More info: Wiki eclipse.ini


Ubuntu 14.04 not shown in operating system list

Run grub-update from your Ubuntu 11.04 that is if grub was the boot manager. Otherwise, you'll need to fix that from the windows boot manager.


Unable to upgrade from 16.04 to 18.04, no real error?

try:

sudo apt-get install lsb-core

and then upgrade

Sometimes this package is missing or corrupted and the installer has hard time figuring out which version is currently running, There are lots of complains about that if you google it. The same might happen in Debian.


Can't retrieve minimized LibreOffice Writer

I don't know if its going to work in the future but maybe try this:

unity --replace & disown

At the moment it fixed the problem with disappearing LibreOffice Writer windows after minimizing them.


Some things to consider.

The connection could "appear" to be worse due to the way the icon displays your connection. You might want to check your actual ping response times and your connection rate to see if it is in fact worse. Open a terminal and issue command

iwconfig

and look for bitrate, and command

ping -c 4 192.168.1.1

(or whatever your router IP address is) and check your response times (you will probably want something in the neighborhood of 5ms or less over wireless). Is it running slowly for you?

If it is, Ubuntu may be using a generic driver where there is a better driver provided by the wireless chip manufacturer. That is something you might want to determine from the system specs of your particular model computer.

More information concerning your PC's model name/number and your actual connection rates might help pin down a better answer.


For some reason your syncdaemon isn't connecting. Please file a bug with details as to versions, etc.; in the meanwhile, you can connect manually entering u1sdtool -c in a terminal.


WebGL stop working after update to Ubuntu 12.04 LTS

Same here, WebGL does not work.  When I start Ubuntu 12.04 with a flash drive on my Netbook 1005HA this demo runs in FireFox: "http://learningwebgl.com/lessons/lesson04/index.html".

After I actually installed 12.04 and ran the updates it no longer runs in FireFox or Chrome.


apt-get upgrade not fully installed but is ok, how to remove?

Just hold these two packages mariadb-galera-server-5.5 and mariadb-galera-server.

sudo apt-mark hold mariadb-galera-server-5.5
sudo apt-mark hold mariadb-galera-server

Now it won't setup mariadb server after running sudo apt-get upgrade command.


No proprietary Nvidia driver available on Lenovo W550s

According to Lenovo website, your graphic card is a NVIDIA Quadro K620M.

You can install the Nvidia driver using the following PPA :

sudo add-apt-repository ppa:graphics-drivers/ppa
sudo apt-get update
sudo apt-get install nvidia-355


Is VPN + UFW (As a Killswitch) broken in 18.04?

You need to add this line to your script.

sudo ufw allow out on <wlan or enp0s3 from ifconfig> from any to <VPN IP>

The complete script looks like this

sudo ufw reset
sudo ufw default deny incoming
sudo ufw default deny outgoing
sudo ufw allow out on <wlan or enp0s3 from ifconfig> from any to <VPN IP>
sudo ufw allow out on tun0 from any to any
sudo ufw enable


Query about a script that makes webcam take an image every x seconds

You have a few solutions here, perhaps the best would be to run your command like this in one line:

while true; do streamer -o `date +%Y%m%d-%H%M%S`.jpg -s 300x200 -j 100 -t 1 -r 10; sleep 10; done


Bug with nginx and naxis, incompatibility problem

Unfortunately, if you want NAXSI and uwsgi support, you have to compile manually the NGINX source code with both naxsi and uwsgi to make it work with the features you want to support.  There is no other way to get all the features one would need on a given NGINX flavor.

NGINX Naxsi is deprecated and unsupported.

Unfortunately, the issue goes back to how SRUs are, and what Debian has done as of 14.04.  NAXSI is and always has been EXTREMELY hard to package, it is not a trivial modification.  Every single time they change a ruleset and such, everything else appears to break along with it, and the nature of SRUs and Debian updates preclude updating the module just to fix a small rules bug.

See this for details on the flavors.

Note that NGINX Naxsi is no longer supported by me or Ubuntu anymore, since it's been dropped and has always been a headache to the NGINX packagers.


Adding Repositories option is not available in Software Center in Ubuntu 16.04 LTS

Yes there is a difference, in 16.04 LTS you will have the Gnome-Software-Center instead of the Ubuntu-Software-Center.

As for adding repositories, this you always can do in System Settings --> Software & Updates --> Other Software


Sudden Violent Audio Volume Jump and Static Noise - Intermittent, but SCARY AF

This is something I’ve seen with some setups over the years when system notification sounds interfere with whatever is being played at the moment. The volume will GO RIGHT UP TO 11 FOR A SECOND, then return to normal. To call it annoying would be an understatement, particularly when it happens at 1:30am.
Fortunately there is a fix:

Open a terminal
Type sudo vi /etc/pulse/daemon.conf (feel free to use any editor, so long as you’re editing with sudo
Set flat-volumes = no
Restart PulseAudio with pulseaudio -k

That should do the trick. Hope it saves you from a heart attack


Software compiled from source does not work after first run

You should not compile the package by yourself. Remove it with

cd mecab-0.996
sudo make uninstall

and then proceed with deb-package mecab from repository. It has exactly the same 0.996 version as your trying hard to compile ...

  xenial (16.04LTS) (misc): Japanese morphological analysis system [universe]
  0.996-1.2ubuntu1: amd64 arm64 armhf i386 powerpc ppc64el s390x

Nkf application is packaged as nkf too. So the solution is simple:

sudo apt-get install mecab nkf

Note: you may be interested in other mecab-related packages (output from apt-cache search mecab):

darts - C++ Template Library for implementation of Double-Array
groonga-tokenizer-mecab - MeCab tokenizer for Groonga
libmecab-dev - Header files of Mecab
libmecab-java - mecab binding for Java - java classes
libmecab-jni - mecab binding for Java - native interface
libmecab-perl - mecab binding for Perl
libmecab2 - Libraries of Mecab
libtext-mecab-perl - alternate MeCab Interface for Perl
mecab - Japanese morphological analysis system
mecab-ipadic - IPA dictionary compiled for Mecab
mecab-ipadic-utf8 - IPA dictionary encoded in UTF-8 compiled for Mecab
mecab-jumandic - Juman dictionary compiled for Mecab
mecab-jumandic-utf8 - Juman dictionary encoded in UTF-8 compiled for Mecab
mecab-naist-jdic - free Japanese Dictionaries for mecab (replacement of mecab-ipadic)
mecab-naist-jdic-eucjp - free Japanese Dictionaries for mecab (replacement of mecab-ipadic) in EUC-JP
mecab-utils - Support programs of Mecab
open-jtalk - Japanese text-to-speech system
open-jtalk-mecab-naist-jdic - NAIST Japanese Dictionary for Open JTalk
python-mecab - mecab binding for Python
ruby-mecab - mecab binding for Ruby language
unidic-mecab - free Japanese Dictionaries for mecab


Getting "Release: The following signatures were invalid" on local repo

Try using this -

/usr/bin/gpg -bs -o Release.gpg Release

Instead of this -

/usr/bin/gpg -abs -o Release.gpg Release

Notice the "-a" difference.

From gpg manpage -

  -a --armor
  Create ASCII armored output.  The default is to create the binary OpenPGP format.

According to this -

  ...The reason why we avoid ASCII-armored files is that they cannot be used directly by SecureApt..

NOTE:

If the above method doesn't work, as an additional step along with the above mentioned method, try adding these two lines to the ~/.gnupg/gpg.conf file -

cert-digest-algo SHA256
digest-algo SHA256


How to discard uninstalled applications from ubuntu 18.04?

If you don't know the exact name of the package try the following from tty:

history 100 | grep matlab

The above will show you which command you used to install matlab, if it was installed through the terminal.
To see every package installed on your system containing "matlab", run:

sudo apt list --installed | grep matlab

From there, you should be able to completely remove the package using dpkg:

sudo dpkg -P "package-name".

For the future, it is highly recommended to only install applications via the apt-cache repository. If you cannot find the package in the apt-cache repository, add the ppa to /etc/apt/sources.list, then run an update.


Ubuntu 15.10: laptop reboots after suspend

I'm on the Ux305ua, had the same issue. Switching off fastboot in bios settings solved it for me.

I got the tip here
https://bugzilla.kernel.org/show_bug.cgi?id=108801


Low-graphics mode error during installation

You can follow this guide to boot with nomodeset kernel parameter when booting from LiveUSB.

Then you will be able to install the system.

If the installed system still does start GUI, then you can use same method.

After all is installed you will probably need to install a proprietary video driver, because it looks like open source drivers do not support your video adapter well.


Requiring password after returning from blank screen not working Ubuntu 14.04, Ubuntu 16.04

I recently experienced a similar issue. The only action I found to permanently resolve the matter was to reinstall 16.04 from a boot-able USB.

Step by step directions for this process can be found here:
 Reinstall Ubuntu with USB


Since newest Teamspeak version was removed from the repository only way to install right now is manual install

Try this

Create a new file name it "Teamspeak3.desktop" and edit the file and add this

[Desktop Entry]
Name=Teamspeak 3 Client
Exec=/<RouteTo>/TeamSpeak3-Client-linux_amd64/ts3client_runscript.sh
Type=Application
Icon=/route/to/icon.png
Version=3

Simpler Solution

Save and Try opening it
Source
http://codetunnel.com/how-to-add-teamspeak-3-to-the-unity-launcher-in-ubuntu/


Yes:

you need to enable it.

Go to the dash (or from a terminal) and run vino-preferences (It is called "Desktop sharing" in the dash):

It should be almost self-explicative.

and

The connection type is VNC, not RDP.

Read also Gnome 3.10 sharing desktop --- how to configure the security type for VNC? --- contains important information.


Does "Erase Disk and Install Ubuntu" replace the default boot screen?

The Erase disk and install Ubuntu option will cause all partitions on the disk to be erased, including the protected system and recovery partitions. It will also delete all your programs, photos, music and any other files in all operating systems, including all other operating systems themselves.

When you install Ubuntu, the GRUB bootloader will replace the existing Windows bootloader, but it will not replace the HP Compaq notebook's splash screen that appears  during boot before the Windows logo appears on the screen. The splash screen is a function of the motherboard that provides a visual cue for accessing the BIOS. Because the splash screen is determined by the computer's hardware, replacing the operating system will not have any effect on whether the splash screen appears when the computer is started.


RE question : transfer exe transfer file from Ubuntu oracle virtual box to host machine (windows 7 )

You can't run Linux programs in Windows (unless you use some kind of emulator) nor Windows programs in Linux (again except if you are using Wine or similar software).


With sed what is difference between sed -n '1,2p;3q' and sed -n '1,2p;2q'

AFAIK they are functionally equivalent. There would be a difference if you did not use the -n option, as noted in the manual (emphasis mine):
       q [exit-code]
              Immediately quit the sed  script  without  processing  any  more
              input,  except  that  if  auto-print is not disabled the current
              pattern space will be printed.  The exit code argument is a  GNU
              extension.
So without the -n
$ sed  '1,2p;2q' file
#comment 1
#comment 1
#comment 2
#comment 2

but
$ sed  '1,2p;3q' file
#comment 1
#comment 1
#comment 2
#comment 2
#comment 3


Ubuntu System BootOrder not found on Acer Aspire F5-573

You did right thing but you struck in renaming process. Please choose a different name... Instead of ubuntu use ubun or as per your wish, because you already used ubuntu. That's why it is not accepting it.


Getting git smudge filter to work in Ubuntu

git checkout HEAD -- ** will only convert files that have changes. Unchanged files will not be touched, that's why nothing is replaced in them. To force updating all files, you could remove them and then reset. But make sure you don't have any uncommitted changes, because they will be lost. For example you could do this:

git rm -r .
git reset --hard

Or, if you prefer, you could replace only all .h and .cpp files with:

rm **/*.{h,cpp}
git checkout .


It should be possible. I can give the Linux commands, you'll have to lookup the equivalent configuration for whichever SSH clients you use on Windows.

From VM to B:

ssh -R localhost:2022:localhost:22 192.168.1.15

This will forward port 22 (presumably SSH) on the Ubuntu VM to port 2022 on 192.168.1.15.

From B to C:

ssh -R localhost:3022:localhost:2022 34.xxx.xx.xxx

This will forward the localhost:2022 (which itself is from was forwarded by the previous command ran in the VM) to 3022 on C.

From A to C:

ssh -L 4022:localhost:3022 34.xxx.xx.xxx

This will forward the localhost:3022 on C to A's 4022.

Thus we have a chain of forwarding:

4022 on A to
3022 on C to
2022 on B to
22 on the VM

Finally, on A:

ssh localhost:4022

This should connect to the VM.

-L is LocalForward in ssh_config
-R is RemoteForward

This chain can be shortened. For example, depending on the network settings involved, you could do, from B to C:

ssh -R :3022:192.168.1.15:22 34.xxx.xx.xxx

B will directly forward 3022 on C to 22 on the VM. And on A:

ssh 34.xxx.xx.xxx:3022


Software Center says I'm not authenicated

Did you get the common Authenticate dialog window offering to input your user password?


Bluetooth is not able to find devices on ubuntu 18.04

This may help you:

Type either one of the following commands:

dmesg | grep -i blue

or

sudo lsusb |grep Bluetooth

The command output will suggest whether your Bluetooth firmware is missing or not. It will be something like:

Bluetooth: hci0: BCM: Patch brcm/BCM.hcd not found

Also see: How can I tell if my laptop has Bluetooth?
If you are indeed missing a firmware (.hcd) file, then try to search and copy the required .hcd file to /lib/firmware/brcm.

Also see this bug report.


Yes, you can be able to create ntfs partitions on your external HDD.Just shrink the size of FAT filesystem and then create NTFS partitions from the free or unallocated space.

It would preserve the data inside your HDD.


How do I enable print selection in Chromium

Until selection-printing will be enabled in Chromium you may be happy with the Chrome/Chromium Print Plus extension that (partly) enables selecting elements from a page to print.

Unfortunately selecting from PDF documents is not so easy and may be limited to whole pages.


How to run a program without typing the full path?

An easy way is to place a link in /usr/local/bin:

sudo ln -s -T /home/chris/netbeans-7.0.1/bin/netbeans /usr/local/bin/netbeans

after that you can execute netbeans with:

netbeans &


You don't edit those files directly. Even if you did get it to work, chances are all of your work would be undone as soon as an upgrade happened. So instead, use override files.

In that same directory (/usr/share/glib-2.0/schemas), make a file. The file name must end in ".gschema.override".

In there, specify your defaults. For example, to set the defaults for indicator-multiload, it's something along the lines of:

[de.mh21.indicator.multiload]
speed=2000
size=20
view-memload=true

There's a pretty good explanation of how to do this, and why it's done this way here:
http://www.burtonini.com/blog/computers/gsettings-override-2011-07-04-15-45

Unfortunately it seems you can't make the settings mandatory at the moment (locks don't seem to work in Ubuntu)


How to start a new program from service(daemon)?

You can use init scripts. In /etc/init/
example.conf

    description     "My app"

start on startup
stop on shutdown
respawn
respawn limit 60 10

exec sudo blablabla


Bash command substitution syntax (for script to determine my global ip)

You need Bash's command substitution in both lines.

MYIP=$(ifconfig eth0 | grep 'inet addr'| awk '{print $2}' | cut -d ':' -f 2)
MYIP=$(curl -s checkip.dyndns.org | sed -e 's/.*Current IP Address: //' -e 's/<.*$//')

You already used the ` ... ` command substitution syntax in your first line, but the $( ... ) syntax is usually recommended over that one.

You may read on about Bash's two syntaxes of command substitution there:
http://wiki.bash-hackers.org/syntax/expansion/cmdsubst


How to backup Windows 8 recovery partion from linux?

My real quick answer would be to use Clonezilla. It's free and it allows you to save a single partition or an entire disk to a USB drive or external hard drive.


Clock disappeared from notification area

make sure you have all of the components of the ubuntu desktop installed. One easy way to do this is to run this in a terminal:

sudo apt-get install ubuntu-desktop

That will likely add back in ubuntuone-client, but then you can just remove ubuntuone-client with

sudo apt-get remove ubuntuone-client

I'd also recommend logging out and back in again to make sure all components are running.


Toshiba Laptop keyboard and mouse intermittently stop working

This used to work for 13.04 and early 13.10:

edit the following line in /etc/default/grub:

GRUB_CMDLINE_LINUX_DEFAULT="nosplash i8042.reset=1 i8042.nomux=1

save and reboot. After upgrading to the most recent packages though, my touchpad has quit working.


New User to Linux in general (Setting up a hardware firewall, needs interface config and ufw config help!)

The Ubuntu server guide has quite a good walkthrough of setting up a firewall:

https://help.ubuntu.com/12.04/serverguide/firewall.html


Whist I do not have an Nvidia card to test on, can point you to this link. My take on this is that the correct driver for your card, a GEForce 6 series card, is the nvidia-304 series driver, which should be the correct driver to work with your card. If you can try the command:

sudo apt-get install nvidia-304

you might be able to quickly recover from the issue you are presently experiencing on another laptop.

UPDATE: Apparently as commented below, that package is not available in 12.10.

If you have a way to tell which package is the same as the Nvidia 304 driver, that is the one you want.

If expediency matters more, you could install the official release from here by following the instructions here.

UPDATE 2: Have you tried booting into recovery mode and determining if that will work?

Also, could you add the Xorg.0.log or the errors from same to the issue? That might prove useful as well.


I just moved the .gnome folder from tty2. Pressed
Ctrl + Alt + F2 to log in into tty2
then used

mv .gnome .gnome.backup

This is /home/myuser/

And voila! it's working again


I get an error trying to install apache2-bin

This issue was resolved using the following response:

how reinstall apache2?

First:

sudo apt-get --purge remove apache2
sudo apt-get autoremove

Then installing apache2 is as simple as:

sudo apt-get install apache2
sudo /etc/init.d/apache2 restart

To test it:

lynx "http://localhost"


Scribus 1.5.5 shows only English (US) spell checker

Aha!
As explained here Spell check and locale language packages are installed here: /usr/share/hunspell/
To install language packages via LibreOffice doesn't work for Scribus.
Language packages have to be installed using Ubuntu's "Language Support".


Format the new drive to ext4 with gparted or any tool you wish.

Then mount the partition at /mnt (or any location you choose)

sudo mount /dev/sbb1 /mnt
sudo chown your_user:your_user /mnt

Then put the kernel source in /mnt

mkdir /mnt/src
tar xjvf linux-source-2.6.22.tar.bz2 -C /mnt/src

Then proceed with your build.

Note: you should run make as follows, it will make the modules.

make -j5

You then use sudo to install

sudo make modules_install

FWIW there are a number of helper scripts, see

Ubuntu Wiki compile kernel

Obviously there are a number of considerations in building a custom kernel, good luck to you.

EDIT: To merge 2 hard drives, use LVM. You will not be able to do LVM as your original install is not to LVM, so mounting the new drive is the best option.


The issue have fixed. I took the steps below.

Download a driver on the site jpezz showed.(Tnx jpezz)
Install the driver like below.

$ sudo dpkg --install epson-inkjet-printer-escpr-1.7.3-1lsb3.2_amd64.deb
Run 'Printers' application.
Choose 'Add printer' and choose 'Local Printers/EPSON PM-A890(EPSON  PM-A890)' and press 'Next' button.
Choose 'Recommended Drivers/Epson PM-A890 - epson-inkjet-printer-escpr 1.7.3-1lsb3.2(Seiko Epson Corporation LSB 3.2)()' for the driver.
Name the printer like 'EPSON PM-A890' and press 'Finish' button.

Now I can confirm that the message 'Epson PM-A890 -epson-inkjet-printer-escpr 1.7.3-1lsb3.2(Seiko EPson Corporation LSB 3.2)' is showed for the information of added printer. I could print a test page without problems.

I don't know why the 'Epson PM A890 - CUPS+Gutenprint v5.3.1' driver which ubuntu installed automatically doesn't work properly, but anyway, escpr driver works well.


SMplayer can't play playlists like ASX 16.04.1 LTS

Found the solution here

http://forum.smplayer.info/viewtopic.php?f=2&t=8363

It needs a newer version (v16) which has the option to pass playlist feature to mplayer in Preferences.

You can get the latest version of smplayer by using the ppa

sudo add-apt-repository ppa:rvm/smplayer
sudo apt-get update
sudo apt-get install smplayer


Cinnamon applets are written in JavaScript. There are a number of fairly complete tutorials:

How To Make A Cinnamon Applet (Force Quit Applet Tutorial)
Hello World Desklet Tutorial
Settings Applet


If you cant use mouse, start typing directory name and press Tab. In this case bash suggest you autocomplete for directories and files inside your location in File System: https://iridakos.com/tutorials/2018/03/01/bash-programmable-completion-tutorial.html

If you talk about terminal emulator, and can use mouse.. Just copy path to buffer (Ctrl+C or Ctrl+Insert) and paste it in terminal command to cursor location using Shift+Insert


Cancel installing pending package with apt-get

You may not have removed the package correctly, or apt-get got interrupted while removing the package. First, I would suggest running the following to process pending operations:

apt-get -f install

Once this is done, use autoremove to make sure there is no garbage in the way:

apt-get autoremove

Then, remove your package completely:

apt-get remove --purge [package name]


The behaviour has been proven to be web application dependant. Upgrading the source code of Zabbix from alpha4 to RC1 has solved the problem.


1.Boot the pendrive with rufus.
2.turn off secure boot in BIOS mode.
Now try to install again.

Thanks.


Short answer: it's telling the shell to check into the existence of  $filename to know whether to choose the then or else statement.

Before the if-statement can be evaluated, the condition needs to be tested -- is it true or is it false? Here, [[ ]] denotes a boolean variable whose value depends on the expression within. Traditionally, [ ] was the bash syntax to issue test command, returning the value of the expression, regardless of type and in any context. Newer versions of bash adopted [[ ]] as a keyword exclusively for if-statements. I'd imagine this prevents type errors, or something.


Ubuntu 18.04: "Add to Favorites" missing for certain qt-based applications?

A convenient workaround for me was adding it to my favorites from the omnibar.


How to clone a hard drive to an image that I can open later?

Use dd (replace sda1 with the partition you want to save):

sudo dd if=/dev/sda1 of=/home/user/backup.img

This will make a mountable image of a partition.
Just be aware that this could take a while, and the image will have the size of the partition, not the files on it. In your case this would be 80GB. If you compress the image it should be about the size of the used space of your hdd.

Refer to DriveImaging: Creating Disc Images Using dd for a more comprehensive explanation.


First time using Java Web Start in Ubuntu - Fatal Launch Exception

SOLVED:
Apparently the Sun Java javaws works. In Firefox:

Edit > Preferences > Applications > "Java Web Start application" > other:

/usr/lib/jvm/java-6-sun/jre/bin/javaws


If you read /etc/rc0.d/README, you'll see that you're not following the pattern.  First, your script should be in /etc/init.d, and there should be a symbolic link to it (created with the ln command) in /etc/rc0.d or /etc/rc6.d.  Also, the script should have a particular header as described in /etc/init.d/README.  All the scripts in my /etc/init.d are owned by root; I'm not sure if that's a requirement, but it couldn't hurt.  (The chown command is used to change ownership of a file.)


How to configure Logitech Marble trackball

This is always what I've done. it works a peach for every trackman I've ever used. It's the last, simplest step from the official ubuntu page.

~/trackman.sh:

#!/bin/bash

xinput set-button-map "Logitech USB Trackball" 1 2 3 4 5 6 7 8 9
xinput set-int-prop "Logitech USB Trackball" "Evdev Wheel Emulation Button" 8 8
xinput set-int-prop "Logitech USB Trackball" "Evdev Wheel Emulation" 8 1
xinput set-int-prop "Logitech USB Trackball" "Evdev Wheel Emulation Axes" 8 6 7 4 5
xinput set-int-prop "Logitech USB Trackball" "Evdev Wheel Emulation X Axis" 8 6
xinput set-int-prop "Logitech USB Trackball" "Evdev Drag Lock Buttons" 8 9`

chmod +x ~/trackman.sh

then, whenever you login (or in a startup script), bash ~/trackman.sh

Done. This tiny little scripts works much, much better than the official ~60mb windows installer IMHO :)


This is probably caused by a bug in the usb-modeswitch package. A fixed version of usb-modeswitch is currently available in my PPA.

Open a terminal window and run these commands:

sudo add-apt-repository ppa:gunnarhj/misc
sudo apt update
sudo apt install usb-modeswitch

Then reboot. Now - hopefully - all you need to do is inserting the dongle, and it should be detected automatically.


Firefox 27.0.1 Address Bar Completion Pop-up Text Blank

Disabling the Delicious Bookmarks add-on seems to have fixed the issue. I haven't been using delicious recently, so disabling is fine for now. I'll look for an update to the add-on.


I can't create bootable USB drive with Startup Disk Creator

I have read that a 2GB flash drive is now minimum for a Live install.
I have not confirmed this.

Alternatly you can boot the 712 MB Ubuntu iso image using grub2.
MultiBootUSB has script for doing this.


Graphics driver problem: full grey screen

As stated in the comments,

sudo apt-get install --reinstall lightdm

sudo service lightdm restart


They are snap packages. core and chromium are snap packages. You can list installed snap packages using
 snap list. You can read more about snap packages here.

Another more detailed answer


Is there any way to have the old "Appearance" app from 10.10 back and use it with 11.10?

No, the 10.10 interface is gone, and unless the GNOME devs add more functionality to the new one, you can't get it back in 11.10. (Also, the new functionality would have to come in 12.04/Precise or later.)

Your best bet at this point is a third-party alternative, if one exists. (I haven't looked.)


Why do user programs talk to the Shell instead of directly to the Kernel?

Disclaimer: I have no idea what I'm talking about. Anyways:
This dynamic seems to involve communication. Communication often has its challenges, these manifesting themselves as e.g. concerns of compatibility (with e.g. various (versions of) clients), and different measures to uphold this compatibility.
Upholding such a system especially through a long time while intending to support a multitude of platforms may end up being an elaborate endeavour. Thus, it's beneficial to create an abstract layer around the kernel that extracts and takes over this responsibility.
All the work aimed at upholding compatibility with the various clients can be done in this extra interface, instead of directly in the kernel, which, in turn can remain as light and uncomplicated as possible, allowing its maintainers to focus on the important work instead of having to get bogged down in the endless hamsterwheel of trying to keep a continuously collapsing eroding house of cards upstraight.
:D Cool, I just said that :D
Now, you could offer, why should it be the problem of the kernel in the first place, why not the problem of the maintainers of all those platforms wanting to benefit from building their projects around the kernel?
Well — I guess — it could be because all these people would need to work against a very inflexible target (remember, the kernel devs are working on important features, not on tending to the wishes of a multitude of third parties)...
So it could be beneficial even for the maintainers of these third party platforms if they could aim their communication efforts towards something that shows more flexibility and willingness to accommodate some of their suggestions should such arise.
Basically, you could look up the concept of an "abstraction". I think it's pretty much overlapping with what I described here.
Again, I have no idea whether this is the case or not; it's just, I feel if I had a kernel, this would be a reason why I would opt for (and enjoy) wrapping it into a shell like that.


I upgraded feom 19.10 to 20.04.1 and matlab (2017b) remained intact. No need to reinstall or anything.


Unable to create directory wp-content/uploads/2016/09. Is its parent directory writable by the server?

To have a directory writable by the web server you would have to ensure the directory is writer by the server's userID.

On Ubuntu the server is run by userID www-data.

Go to the directory where you want the server to have write access and change the owner and group to www-data.  Your error message is saying parent directory.  So you will have to be sure to do this for the parent directory of where the file is actually running.

Run this command on your wp-content directory:

$ chown -R www-data:www-data wp-content

That will change the owner of wp-content as well as all the other files and directories including the uploads/2016/09 and their subdirectory to be owned by the web server and resolve the error.


how to build simple program run from terminal in ubuntu

Firstly, save your code in form of a file. Let's say the file name is xyz.c
Open the terminal and change the directory to the location where your file is(use cd command).
After that compile as g++ xyz.c
This will compile your code. Doing that will produce an executable file a.out, which you can run by typing ./a.out


12.04 No Audio from HDMI After Switching Monitor Off / On

Run this command in terminal : alsamixer

and check if the master-sound is set to mute. (oo is unmute and mm is mute)


When I paste a command instead of typing it why does it not get added to history

There should be no difference between a copy-and-pasted command and a typed one.  However, if you start a command line with a space, that command is not saved into the history.  It's quite easy when copying and pasting to accidentally put a space at the beginning.


Documents queue to shared printer but won't print

Are you connecting to the printer using from the network like //COMPUTER-NAME/PRINTER-NAME ?

I had the same issue with print jobs not printing wirelessly to my shared printer HP K550 connected to my desktop pc running Windows 7.  I first attempted to access the printer using //COMPUTER-NAME/PRINTER-NAME .  I could see the printer but nothing would print.  I then changed the path to //xx.xx.xx.xx/PRINTER-NAME (where xx.xx.xx.xx is you IP address of the computer the printer is connected to).  Now it prints fine.

My printer Settings are below and are based on a HP K550:
Device URI: smb://192.168.1.3/HP_K550
Make and Model: HP Officejet Pro k550, hpcups 3.12.6


Problem with Qualcomm Wireless Adapter with Ubuntu 14.04 LTS

ath10k_pci 0000:03:00.0: firmware crashed! (uuid n/a)

I suggest that you update the firmware. With a temporary working internet connection by ethernet, tethering or whatever means possible, open a terminal and do:

cd /tmp
wget http://security.ubuntu.com/ubuntu/pool/main/l/linux-firmware/linux-firmware_1.169.1_all.deb
sudo dpkg -i linux*.deb

Reboot and tell us if there is any improvement:

dmesg | grep ath


How do I right click with a Magic Trackpad?

Right Click with Two Fingers does work with the Magic trackpad by default in Ubuntu 11.04. Under Mouse Preferences in the Control Panel you will also find a "Touchpad" tab with more configuration options.

Try removing all trackpad entries from your /etc/X11/xorg.conf file. Some  settings that were needed for earlier versions of ubuntu are not needed to get the Magic Trackpad to work and some legacy settings cause unexpected problems like yours - left and right click not working as expected.


What is the formal definition of "critical update"?

The importance of an update reflects the importance of the bug(s) fixed by that update.

A 'critical' update fixes a 'critical' bug.

Bug importance is defined at https://wiki.ubuntu.com/Bugs/Importance. A Triaged bug is usually assigned an importance (Wishlist, Low, Medium, High, Critical) based upon the severity of the problem and the estimated number of users affected. Importance helps developers establish the priorities for their work.

Critical: A bug that has a severe impact on a large portion of Ubuntu users

Causes data corruption
Crashes the entire operating system
For example, if the system fails to boot, or X fails to start, on various makes and models of computer
Renders the system temporarily or permanently unusable
Severely affects applications beyond the package responsible for the root cause

Ubuntu generally releases fixes for most High and Critical bugs to the current releases of Ubuntu in the form of a patched package: Foo version 1.1.3 gets patched to 1.1.3a, not to 1.1.4 (that would be a new upstream release).

A few applications (like Web Browsers) get the latest upstream release (instead of patched versions) for all supported releases of Ubuntu.
Security patches are released are released to all supported version regardless of the original bug's importance.

Graphics drivers (ALL "drivers") are kernel modules, and handled by the Ubuntu Kernel Team. See https://wiki.ubuntu.com/Kernel for their workflow and bug-handling policies.


Second monitor has vertical separation 14.04 on Thinkpad T410

Seems like it accidently, changed the order of your screens. Go to screen settings and change the order.


Best resource I found on this issue is at this URL. The issue seems to be that we have references to hardy packages in /etc/apt/sources.list, and solution is just to remove them.

https://bugs.launchpad.net/ubuntu/+source/sysvinit/+bug/1001904

I only had the sysv utilities issue, but just removed 4 lines referring to hardy from /etc/apt/sources.list fixed it.


Facebook have deprecated the API that was used by empathy. This is why this is  no longer possible. https://developers.facebook.com/docs/apps/api-v1-deprecation

Facebook encourages you to use Facebook Messenger.


If you have an administrator account, simply

sudo command

runs commands as root after asking your password (for safety).

If your account is not an administrator account, you can't :-).

Notice: in a standard Ubuntu installation, the user you set up in the installation process is an administrator account. Guest account is not. Other users, depends on how you create them.

Notice too: "administrator" account in this context mean an account which has the privilege to become root. There is a lot more info in https://help.ubuntu.com/community/RootSudo and in https://help.ubuntu.com/community/Sudoers. I am using the simple "administrator account here" because it's how it's called in the graphic interface to create a new user:


Boot from Ubuntu live USB stick ('Try Ubuntu'). How to see USB disk contents?

There are two things you should know:

1) To look in a USB stick, it has to be mounted. Try mounting it with the mount command. Look in your /dev/ directory for the file to mount, it will be title sdXY, where X is a letter, usually 'b' or 'a' and Y is optional, but typically a number between 1 and 9.

2) As mentioned above, if you had files on the USB before making it a live USB, the files are reformatted and essentially gone. You can use gparted or a similar program to partition the drive which allows for storing files and having a Live Drive on the same key.


Failure to Install opencv 2.4.9 on ubuntu 14.04

I finally was able to install opencv-2.4.10 with the help of these two posts:
1. http://answers.opencv.org/question/37115/opencv-249-make-error/
2. http://docs.opencv.org/doc/tutorials/introduction/linux_install/linux_install.html

Briefly here is what to do:
(1) Pre-requesites

sudo apt-get install build-essential

(2) Git clone the latest copy

cd ~/<my_working _directory>
git clone https://github.com/Itseez/opencv.git

(3) create build files

cd ~/opencv
mkdir release
cd release
cmake -D CMAKE_BUILD_TYPE=RELEASE -D CMAKE_INSTALL_PREFIX=/usr/local -D WITH_IPP=OFF ..

(4) start installing

make -j4
sudo make install

(5) link opencv to python path

export PYTHONPATH=$PYTHONPATH:/usr/local/lib/python2.7/site-packages

(6) Build documentation (optional )

make docs
make html_docs

(7) Enjoy


Cannot connect to wired ethernet on ubuntu 16.04

It looks like a DNS issue. You can ping ip addresses, but can't use the internet due to your host not being able to resolve domain names. Check your DHCP server (most likely your router) and ensure that the DNS server(s) defined are functioning properly. You should be able to do a ping test directly from your router. Instead of pinging an IP, try pinging a domain name (google.com). If that fails then you have a DNS problem. Change your DNS servers to point to Google's DNS (8.8.8.8,8.8.4.4) and you should be golden.


Mouse snagging on autohidden vertical dock between monitors

Since Ubuntu's dock is a fork of "Dash to Dock", it has the same configuration options. Editing them is just slightly more convoluted:

Open a terminal
Run this to disable require-pressure-to-show:

$ gsettings set org.gnome.shell.extensions.dash-to-dock require-pressure-to-show false

Run this to enable intellihide:

$ gsettings set org.gnome.shell.extensions.dash-to-dock intellihide true

Enjoy finally having a usable multi-monitor setup!


Remove `Terminal - ` from xfce4-terminal's window title

In XFCE Terminal's Preferences, are options to control the title:

Change the Dynamically-set title to Replaces initial title.


I guess you're running a 32-bit Ubuntu. This repository only has 64-bit packages. Search for "mono-complete" in http://debian.meebey.net/experimental/mono/Packages and you'll see:

Package: mono-complete
Source: mono
Version: 3.0.6+dfsg-1~exp1~pre1
Architecture: amd64              <--- 64-bit!


difficulty in downloading software packages

@deepak, could I assume that you are using the Ubuntu software center? If not, could clarify the question? Once in the Ubuntu Software Center, click Edit, and then click on Software sources and ensure that all sources are checked on that screen.


Upload to localhost with ssh, locked account

OK, there is already way too much for a single comment. Let's untangle the confused discussion. There are two problems here: (i) access and (ii) permissions on the server.

FTP vs SFTP. Although the names are similar and both "things" look very much alike, these two ways of accessing your server are handled by two very different programs.

FTP is run by an FTP server; it is both old and simple
SFTP on the other hand is run by an SSH server and over an SSH connection. It is more versatile and more secure. You will be well advised to access your web server using SSH/SFTP.
you can use SSH both to connect directly to the server, log in and run commands, as well as run SFTP just for transferring the files. Heck, you can even mount the server like a network drive using SSH!

Testing the SFTP connection. If you can log in as simon, you should be able to transfer files to and from /tmp and /home/simon. If this doesn't work with your program, please open a terminal and type

# create a fake file for testing
dd if=/dev/zero of=test.bin count=128
scp test.bin simon@server:/tmp
scp test.bin simon@server:/home/simon

If these work (as they should), then your problems are either due to your ftp program, or due to permissions on the server.
Once you are logged in and gained access to the server, but can't modify the files you wish to modify, you might want to log in with ssh first to look around what is happening. Open a terminal, and type

ssh simon@localserver

Enter password, log in and try to create and modify files, and look who the files belong to:

touch /tmp/test
touch /var/www/test
ls -l /var/www


I would recommend to use packages from Ubuntu repositories.
The 18.04 LTS have LHPADF packages.
We can download them to Ubuntu 20.04 LTS to install:
cd ~/Downloads
wget http://archive.ubuntu.com/ubuntu/pool/universe/l/lhapdf/liblhapdf0v5_5.9.1-6_amd64.deb
wget http://archive.ubuntu.com/ubuntu/pool/universe/l/lhapdf/liblhapdf-dev_5.9.1-6_amd64.deb

sudo apt-get install ./liblhapdf0v5_5.9.1-6_amd64.deb ./liblhapdf-dev_5.9.1-6_amd64.deb

and then compile JEWEL:
sudo apt-get install gfortran build-essential

cd ~/Downloads
wget https://jewel.hepforge.org/downloads/?f=jewel-2.2.0.tar.gz -O jewel-2.2.0.tar.gz
tar xvzf jewel-2.2.0.tar.gz
cd jewel-2.2.0/
make

to  use it by ./jewel-2.2.0-vac or ./jewel-2.2.0-simple.


cannot connect to network in ubuntu server 12.10

Check the content of /etc/udev/rules.d/70-persistent-net.rules files to get the names assigned to your network devices by udev. Usually, those should be eth0 for wired and wlan0 for wireless.

Then, put the following content into the /etc/network/interfaces file (replace eth0 and wlan0 names if needed):

auto eth0
iface eth0 inet dhcp

auto wlan0
iface wlan0 inet dhcp

Tha above will work fine if only you have the DHCP server in your network. If no, you can assign static IP address according to the following example:

auto eth0
iface eth0 inet static
 address 192.168.0.2
 netmask 255.255.255.0
 gateway 192.168.0.1


Ubuntu 16.10 won't boot after motherboard replacement - GRUB issue?

Sounds like your drive is ok but the laptop is not detecting it; possibly something went wrong with the mobo swap. Can you see during post or get in bios to see if the drive gets detected there? I'd try booting up another computer from the disk (usually works out-of-the-box) to make full backups.


How do I prepare for installing Ubuntu from Windows (Wubi)?

Will I need to download/install anything else first?

No. But once you run the installer, it will download approximately 500 MB of data.

  Do I simply select "Boot Ubuntu" and then go about my business?

Yes, Windows Boot Menu will give you an option to do that when you start up.

  Will my HDD need partitioning beforehand?

No.

  If I save files while running Ubuntu where do they go when I decide to boot Windows instead?

They stay on the Ubuntu "disk" (which is actually a large file on your Windows drive); if you wish to "share" them it's easiest to use a USB flash drive or similar. Alternatively, set up a FAT32 partition which both operating systems can access, but that may be getting too complicated...


Possible to run a script when something plugged in / disconnected from Mini DisplayPort?

Yes it should be possible using udev.

I have asked/answered here a similar question (change sound output on HDMI (dis)connect). First you will need to create a udev rule like this:

SUBSYSTEM=="drm", ACTION=="change", RUN+="/usr/local/bin/update_screen_config"

It should be on the same location as in my answer but you can change the name. To know exactly which SUBSYSTEM and ACTION you need use udevadm and connect your DP. In my system, connecting the HDMI screen I get:

$ udevadm monitor
monitor will print the received events for:
UDEV - the event which udev sends out after rule processing
KERNEL - the kernel uevent
(here I connected my screen)
KERNEL[16383.092226] change   /devices/pci0000:00/0000:00:02.0/drm/card0 (drm)
UDEV  [16383.281930] change   /devices/pci0000:00/0000:00:02.0/drm/card0 (drm)
(disconnected my screen)
KERNEL[16389.092226] change   /devices/pci0000:00/0000:00:02.0/drm/card0 (drm)
UDEV  [16389.281930] change   /devices/pci0000:00/0000:00:02.0/drm/card0 (drm)

The second part is the creation of /usr/local/bin/update_screen_config (you can give it other name or location). I have used a Python script but you can use anything you want, since it can be executed. This will be the script that is called when the cable is connected/disconnected, so it must find the current state and use xrandr to do what you need. See how I made the detection of the state of the screen and if it suits your needs.

Note: this script is executed as root by udev, so test it as a normal user before you put him on udev.


Windows 8 Legacy BIOS mode and Ubuntu 12.04 LTS dual boot

I have had dual-boot setup before and I have never had a issue. You should be perfectly fine unless you accidentally select the wrong partition when installing Ubuntu and erase Win8!!!


Wifi not working on Toshiba Satillite s55 with ubuntu 13.04

Could you please specify your wifi-card model?

If you don't know how just type into terminal lspci -v | grep -i wireless


What charms will be best for study for testscalability/performance

We've worked on this with hadoop:

http://markmims.com/cloud/2012/06/04/juju-at-scale.html

But it really depends on what you wanna test.

IMO there are so many things that would scale well using juju, it's hard to pick one in general... here're a few that would be interesting to see:

hadoop w/ something other than terasort :)
cassandra
mongodb
hive
lamp (mediawiki for instance)

Please write up your results and post them on the Juju mailing list!

(sorry for the self-link above, but it really is pertinent to your question)


The root is locked because your Ubuntu is running from it.
/media/ is the mountpoint for automounting USB drives, a.o. Currently your P9 is also mounted there.
You must boot from the Ubuntu Live USB to be able to manipulate the root partition. Unfortunately the swap partition P10 is in between P8 and P9, so the required actions are a bit more than you might expect:

NB
The actions you are about to take can irreversibly corrupt your system.
Make sure you backup any files you don't want to lose !!

As said, boot from Live USB, select the Try Ubuntu option.
Start gparted
Select P9 and delete it. Execute (Green tick).
Select P10, Resize/Move, select the slider in the middle and move it to the right. Execute. You should now have Unallocated space between P8 and P10.
Select P8, Resize/Move, select the right arrow of the slider and move it to the right. The size indicator should grow. Execute. You should now have a larger root.
Exit gparted and reboot the system.

Addition as suggested by heynnema (also see comments):
"In terminal issue a sudo mkswap /dev/new_swap_partition_name_here, note the new UUID. Edit that UUID into /etc/fstab with gksudo gedit /etc/fstab and edit the line with "swap" in it. Replace the UUID that's there now. Save the file and quit gedit. Then type swapon -a. Then use free -h and swapon to confirm swap usage."


apt-cache search  doesn't detected package built from source and installed using dpkg -i

if you want to list liblucene (liblucene++0) relevant packages run:

apt-cache search liblucene

or:

apt-cache search liblucene++0*

if you want to check package liblucene++0 run:

apt-cache policy liblucene++0


The Solution:

First:

sudo apt-get install netcat

And then:

sudo cat my_file.pdf | netcat -w 1 printer_ip 9100

This worked perfectly for me :-)


Are you using Unity 3D edition? If yes, you already got viusal effects activated (like a good looking alt-tab windows).
You can play with these effects by using CompizConfig SettingsManager (from Software Center). But be carefull. It's easy to break your settings and thus leaving you with a non working environment)

If you're usind Unity 2D edition you have to select the 3D edition on the login screen.

Good luck.


Ubuntu 13.04 near-fresh install: 'ps aux' gets stuck on anacron

Are you using kerberos?  I had the same problem when made this change in /etc/krb5.conf...

[libdefaults]
 default_realm = MYREALM
 dns_lookup_realm = true

...to...

[libdefaults]
 default_realm = MYREALM
 dns_lookup_realm = false

I was having problems with firefox hanging, and I thought that might be the solution.  Rebooting didn't fix the "ps hanging" problem, but reverting that change and rebooting did.


What is the equivalent __LINE__ (php) in bash ?

In bash you can use the variable $LINENO for this purpose:

echo Installing NGINX. Line: $LINENO

$LINENO holds the current line number, see man bash:

  LINENO
  Each time this parameter is referenced, the shell substitutes a
  decimal number representing the current
            sequential  line  number  (starting with 1) within a script or function.  When not in a script or func‐
            tion, the value substituted is not guaranteed to be meaningful.  If LINENO is unset, it loses its  spe‐
            cial properties, even if it is subsequently reset.

Example

#!/bin/bash
echo $LINENO; echo $LINENO

echo $LINENO

When executed this script prints:

2
2
4


I installed libsane1 and sane-utils fom artful-proposal.
Then I recognized that "sudo scanimage -L" worked, but "scanimage -L" without sudo did not work.
So I created /etc/udev/rules.d/55-libsane.rules with the content:

  SYSFS{idVendor}=="04b8", MODE="0666", GROUP="scanner", ENV{libsane_matched}="yes"

Where "04b8" is the USB id of the scanner manufacturer epson. If you have a brother scanner, you have to replace this id with the one scanimage prints out.


Is there any Adobe Illustrator-like software in Ubuntu?

The two most popular in linux are gimp and inkscape , both are in the ubuntu repositories. I hope they will fit your needs, but I know many people feel adobe makes great products and that the linux offerings do not measure up to what they are accustomed to.


Incomplete install and I cannot see part of the hard disk

Try installing this software 'PARAGON PARTITION  SERVER' and scan this hdd and see if it sees the other partition, if that 512gb partition is seen format it in NFTS format


Use Intel RST while dual-booting Ubuntu?

Fallacy: You can't accelerate Windows & Ubuntu concurrently
You can use use Intel RST to accelerate a Windows drive to SSD (usually PCIe mSata on a laptop) and Enhance IO to accelerate Linux (Ubuntu) concurrently, but not simultaneously of course.
There are caveats such as whenever you need to update grub (install a new kernel, update initramfs for some drivers, etc). You need to decelerate the SSD in Windows (with Intel RST software) or BIOS by pressing Ctrl+I during POST (Power On Self Test).
Finding error messages during Ubuntu Boot
By default error messages are hidden for most users during grub boot and a "purple splash screen appears" during the second half of grub boot. To remedy this use:
gksu gedit /etc/default/grub

Look for the line containing:
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

There may be other options on this line which you should not touch. Remove the options "quiet splash" in order to see error messages during boot up. Leave the double quotes (") at the beginning and ending of the parameter list.
Save the file, exit and then type:
sudo update-grub

NOTE: When using Intel RST you must first decelerate the Windows drive before typing update-grub or update-initramfs when grub is installed on the same drive as the accelerated Windows.
Summary
I'll update this answer as new information is provided by the OP. Coincidentally it was disk acceleration under Ubuntu 14.04 that brought me to Ask Ubuntu in the first place. You can search my very first couple of posts here for information on using Enhance IO to accelerate Ubuntu.


I don't know how did you setup your monitors but you can use xrandr to turn off an screen like this:

xrandr --output VGA1 --off

which turns off the monitor connected to VGA1. you can change VGA1 to eDP, HDMI, etc.


Solved by OP in comments

  I don't know why, but the problem was solved by pressing F6 twice.

FYI, this is because the keyboard has a number pad built in. F6 disables this, and means you can type your letters rather than numbers.

  Press the Caps Lock key. num. (F6) to activate the keypad.

Source


How can I use Ubuntu 12.04 to install its driver for a wireless usb adapter in a Ubuntu 10.04?

Remove the device and in a terminal, do:

gksudo gedit /etc/udev/rules.d/network_drivers.rules

Add one long line:

ACTION=="add", SUBSYSTEM=="usb", ATTR{idVendor}=="07d1", ATTR{idProduct}=="3c16", RUN+="/sbin/modprobe -qba rt2870sta"

Caps, brackets, punctuation, etc. are crucial. Proofread twice, save and close gedit.

gksudo gedit /etc/modprobe.d/network_drivers.conf

Add one long single line:

install rt2870sta /sbin/modprobe --ignore-install rt2870sta $CMDLINE_OPTS; /bin/echo "07d1 3c16" > /sys/bus/usb/drivers/rt2870/new_id

Proofread twice, save and close gedit. Insert the device. If it doesn't start immediately, you might have to do:

sudo modprobe rt2870sta


Rhythmbox keeps putting itself back into the sound indicator

If blacklisting doesn't work you can -

Open Rb > Tools > Plugins

Scroll down, find & disable the Mpris Dbus.. plugin, close Rb

Then in dconf editor remove rhythmbox.desktop from interested-media-players, a log out/in may then be required, may not.


Determine current keyboard shortcuts in gnome-terminal using gsettings

I found a solution based on this answer. It seems like a full path must be given:

$ gsettings get org.gnome.Terminal.Legacy.Keybindings:/org/gnome/terminal/legacy/keybindings/ next-tab
'<Primary>Right'

I am not sure how to determine the full path for a relocatable schema (I simply copied the code from the above linked answer and it worked), if anyone can explain this better please feel free to edit this question or provide your own answer. It would also be interesting to know why not specifying a full path will give you the default value for the keybinding.

Also note that <Primary> refers to the Ctrl key, see this question for more information.


Well.. I've found out why.
I removed accidentally the repository

deb http://ppa.launchpad.net/skunk/pepper-flash/ubuntu trusty main

Now it is up-to-date.


Installed entire font family, but only one appears

In OO, the menu is Format -> Character, from where you can pick out different styles.

Original answer was:

Have you updated your font cache?

sudo fc-cache -fv

And above all, what procedure do you used for installing fonts?


How I can run ubuntu in chroot on Android?

You can't really run upstart itself in a chroot. For it to work, you'd need something like an LXC container. Unfortunately most Android kernels don't have the required options to allow LXC to work.

Without LXC, the way of getting a chroot on your phone is to run:

sudo debootstrap --foreign --arch=armhf precise precise
then copy precise/ to your phone
then on your phone (as root): chroot precise debootstrap/debootstrap --second-stage

That will give you a standard Ubuntu chroot on your phone, that you can then chroot into with "chroot precise /bin/bash".

You'll then need to mount /proc and /sys for it to be somewhat usable.

Should you be lucky enough to have a phone where the kernel and userspace works with LXC and can get it manually installed on your phone, the following should work:

lxc-create -t ubuntu -n my-container -- -r precise -a armhf
lxc-start -n my-container

This will create an Ubuntu 12.04 armhf container and start it, you'll then get the usual login prompt (login/password is ubuntu/ubuntu by default).


How do I get rid of frequent error messages?

Inspired by the answer by @ovc I looked up how to disable apport and found  this question.

I had to edit /etc/default/apport and change

enabled=1

to

enabled=0

This way it is not started at boot. For not having to reboot simply stop the service with

sudo service apport stop

Let's see if the messages disappear now :-)


Ubuntu installed alongside an infected Windows system

The safest option would be to install Ubuntu on a different partition, but according to this post it seems safe. Here I quote it:

Wubi will not be affected by Windows viruses. Wubi is almost identical to the standard Ubuntu installation, except for the fact that everything is inside a file on the Windows partition. Therefore it cannot run windows executables (including viruses). The only way you can get a virus from Wubi is if you download something containing a virus, transfer the file to Windows, boot Windows, and then run the virus from Windows.

Also see this thread

EDIT
Also if you want to run any programs in wine from your infected Windows installation, especially as root, you may open your system to infection. Also, the safest option is to format everything and then install Ubuntu - ObsessiveFOSS


Davinci Resolve not Starting (Aborted (core dumped))

DaVinci Resolve requires an NVIDIA graphics card on Linux and the original NVIDIA drivers. Nouveau drivers aren't supported. It won't run on your hardware.

Resolve runs fine on Ubuntu, but you'll also need to install the dependencies yourself. Here is a good HowTo for doing so.


Many directories have a ".d" suffix/extension. What does it mean?

This is often used for directories (hence the "d") that contain a collection of partial configuration files.  All files in the directory get combined, sometimes also with other files, to make the complete configuration.  This is often done when traditionally there was only one configuration file (e.g. in your example sources.list) but there is a desire to make things more modular later.

As Laurence mentions, the /etc/rc?.d directories was probably one of the first times this custom was used.


Print screen key can no longer select a region to capture

This is already built in.  To take a region screenshot, just use SHIFT-Printscreen.  It will then allow you to drag a square on the region you desire.


External HD not mouting - Actual VCN different from expected VCN

I found a solution after after all: running

    chkdsk F:/f

in the terminal of a Windows 10 machine (where F is the name of the drive) fixed the external HD.


Passwordless SSH only works when I'm already logged in on SSH

This is common issue with encrypted home, and was answered many times, for example on Unix, but is covered even in official Ubuntu documentation.

This is probably caused by the fact, that your home directory (and therefore the key) is not accessible during the login time. This can be caused by the fact, that your home is mounted from network drive (on shared system) after login or your home directory is encrypted (usually installs of workstations).
Solving this is complicated, but I will have a look for some discussion. Solution is to move the AuthorizedKeysFile to some other place, that will be accessible or us global store for keys (/etc/security/authorized_keys), or some kind of SSO management system (IPA, LDAP), which will get your key from directory server (yes, can be local). Depends on how much control of the target system you have.
Probably best solution is to store your keys in other place, changing the value in sshd_config:
AuthorizedKeysFile /etc/ssh/%u/authorized_keys

Anyway, if you will move your authorized_keys, make sure they have proper permissions and count with the fact, that if you log in using public key, you will not be able to access your home directory (it is encrypted by your password!), unless you change the way how it is encrytpted.


How to find the maximum data transfer rate possible from the RAM of my laptop

Open terminal and Run the following commands:

sudo dmidecode --type 17

You can just grep speed and skip all other the details using the following syntax:

 sudo dmidecode --type 17  | grep -i speed

Sample output: for sudo dmidecode --type 17

 dmidecode 2.9
 SMBIOS 2.4 present.
 Handle 0x0018, DMI type 17, 27 bytes
 Memory Device
    Array Handle: 0x0017
    Error Information Handle: Not Provided
    Total Width: 64 bits
    Data Width: 64 bits
    Size: 2048 MB
    Form Factor: DIMM
    Set: None
    Locator: J6H1
    Bank Locator: CHAN A DIMM 0
    Type: DDR2
    Type Detail: Synchronous
    Speed: 800 MHz (1.2 ns)
    Manufacturer: 0x2CFFFFFFFFFFFFFF
    Serial Number: 0x00000000
    Asset Tag: Unknown
    Part Number: 0x5A494F4E203830302D3247422D413131382D
Handle 0x001A, DMI type 17, 27 bytes
Memory Device
    Array Handle: 0x0017
    Error Information Handle: Not Provided
    Total Width: Unknown
    Data Width: Unknown
    Size: No Module Installed
    Form Factor: DIMM
    Set: None
    Locator: J6H2
    Bank Locator: CHAN A DIMM 1
    Type: DDR2
    Type Detail: None
    Speed: Unknown
    Manufacturer: NO DIMM
    Serial Number: NO DIMM
    Asset Tag: NO DIMM
    Part Number: NO DIMM

As suggested by @Serg you can use the following command:

sudo lshw -c memory | awk '/clock/'

Reference here


First log into the server, then go to the shared folder /mnt/a/folder and ensure you you have write access.

I tested your fstab entry and got the same error you're describing.  Then I tested the change and get the response you are looking for.

Your fstab entry:

[user]@server:/mnt/a/folder  /mnt/folder fuse.sshfs  defaults,default_permissions,_netdev,allow_other,uid=[user],gid=[user]  0 0

The change:

[user]@serer:/mnt/a/folder /mnt/folder fuse.sshfs  defaults,default_permissions,_netdev,allow_other,uid=[user],gid=[user]  0 0

Change the [user] to the user with ssh access.  Of course, don't include the brackets.

By the way, I understand you've already checked and verfied that [user] on the local computer and [user] on the remote computer has the same uid and gid, whereas they were inadvertently different for my environment.  But something is going wrong and the only detail that I can see is this which works when using the added assurance of the specific user and group ID by the name as it appears on the server.


Swap Partition in between Ubuntu and Unallocated drives

Including the unallocated space to the Ubuntu root partition would require 1) removing the swap partition, 2) moving the Ubuntu root partition to the front, then 3) expanding the Ubuntu root partition, optionally leaving some space to 4) create a new swap partition.
The problem here is 2). Moving a partition can be a lengthy process, and it may fail. The other operations are a matter of minutes.
Alternatively, you limit yourself to creating a data partition with a linux file system (most commonly ext4) in the allocated space, and use that partition as extra data storage. In Linux, any storage on different partitions can easily be made available from within the home directory of the user using symbolic links. Symbolic links for daily usage act and feel as regular folders. The user is not aware that, moving into these links, he/she may be redirected to a totally different place in the file system, even on different partition that can be on a different drive.


How do I stop the wallpaper from changing constantly?

Try right-clicking on the desktop and choosing change desktop background and choose one that you like that does not appear in a stack. If it looks like a stack of pictures, then it's a slideshow and it'll keep changing.

Right-clicking on the desktop and choosing Change Desktop background will bring up the window that you see below. The image selected in the screenshot is a single image whereas the one below it(the one of scyscrapers) is a slideshow. Choosing an image that's not a slideshow will solve your problem


Random freezes followed by loss of WiFi connection with a BCM4313 wireless card

There are some others facing difficulties with that chipset in Natty. Take a look at this question for info on how to solve your problem.


How can I get my ATI / AMD drivers to work with any kernel above 3.2.0.x?

There are two driver options that usually work well:

the opensource radeon driver
the fglrx package from the official repository

A 64-bit kernel usually gets much better support in this case.

You can also try the 12.6 beta drivers from AMD.

If you need a guide, try the Unofficial Wiki for the AMD Linux Driver.

Do not install a new driver package over an old one.  Remember to uninstall the previous package(s).


Why Do I Have No Exit Code From debootstrap?

If you just want to test for an exit code, bash has the following simple syntax:

if debootstrap --verbose --arch=${ARCH} ${RELEASE} ${chroot_dir}
then
  echo Success
else
  echo Failure
fi

The reason why the other way doesn't work is because set -e causes the script to exit before the exit code is tested.

For further reading about exit values and error trapping see the following links:

http://mywiki.wooledge.org/BashFAQ/105
https://sanctum.geek.nz/arabesque/testing-exit-values-bash/


This is the RPM database. Did you install any RPMs recently?
Background: You can install RPM as a secondary package manager on Ubuntu, and then you can install RPM packages as well as the usual DEB packages.
Check with rpm -qa if (a) RPM is installed and (b) what RPMs you have installed.


Install deb package with all dependencies in same folder?

Indeed you have many solutions:

Copy all .deb files from /var/cache/apt/archives to the new  pc to  the directory /var/cache/apt/archives, or just copy the .deb of vlc dependencies only instead of copying all those debs. you can know the dependencies of vlc by command apt-cache rdepends vlc.
Now once you have those debs in the /var/cache/apt/archives of the second system then you can run sudo apt-get update then sudo apt-get install vlc.

BUT this only works if the two systems have same  OS version and same package  version with same updates.more info

Another solution which is better is to make your own repository so you can install any application you want without fearing of dependencies hell when offline installation. take a look: https://askubuntu.com/a/648969/150504


14.04 different outcome depending on regional apt repository

https://askubuntu.com/a/37754 solved my issue.
enclosed a short snippet from the original answer:

  on the top in your /etc/apt/sources.list file should be all that is needed to make it automatically pick a mirror for you based on your geographical location.

deb mirror://mirrors.ubuntu.com/mirrors.txt trusty main restricted universe multiverse
deb mirror://mirrors.ubuntu.com/mirrors.txt trusty-updates main restricted universe multiverse
deb mirror://mirrors.ubuntu.com/mirrors.txt trusty-backports main restricted universe multiverse
deb mirror://mirrors.ubuntu.com/mirrors.txt trusty-security main restricted universe multiverse


You can use pam_succeed_if module (see manual page) before the pam_google_authenticator to skip this part for your group:

# the other authentication methods, such as @include common-auth
auth [success=1 default=ignore] pam_succeed_if.so user ingroup group
auth required pam_google_authenticator ...


ntfs-3g-mount: mount failed: Permission denied

Try sudo mount -t ntfs /mnt/tmp/dislocker-file /media/bitlocker


what is the command to be able page up/down a long text?

I'm not sure if I understand what you mean but when you do

man ls

you can use following commands:

space to advance one page

d to advance half a page

b to go back one page

u to go back half a page

arrow keys to go up/down with one line at a time


Try this command, if you run Unity, as it will restart Unity:

sudo killall unity-panel-service

was found in this forum, link


Why doesn't gcc or build-essential install the latest version of GCC (9 as of today) on Ubuntu 18.04 LTS?

On any given Ubuntu release, build-essential provides the most commonly needed tools for building packages for that release, by declaring dependencies on various other packages.

Two of the packages build-essential always depends on are gcc and g++. On each release, those packages provide (parts of) the GNU Compiler Collection at the default version for that release, which is the version that is typically used to compile programs for that release. In particular, it is the version that is used to build all the binary packages provided in Ubuntu's official repositories. Another way to say this is that it's the version that is used to build that release of Ubuntu.

Others have pointed out why Ubuntu releases deliberately often do not provide the very latest versions of software. Although the StableReleaseUpdates policy does apply to packages that provide development tools, that nonetheless doesn't really answer why build-essential doesn't always depend on the latest tools, because build-essential often doesn't even depend on the latest tools that are officially packaged for the release.

For example, as I write this, the latest stable version of Ubuntu is 19.04. (It's not an LTS release, but it's a stable release.) The gcc and g++ packages, which build-essential depends on, provide GCC 8.3 on Ubuntu 19.04. However, GCC 9.1 is packaged in the official repositories for Ubuntu 19.04; it is provided by packages whose names end in -9. In particular, for GCC 9.1 instead of GCC 8.3, you would install the gcc-9 package instead of the gcc package and the g++-9 package instead of the g++ package. (You don't really have to install one version instead of the other; gcc and gcc-9, as well as g++ and g++-9, can be installed at the same time with no conflicts.)

It's true that the stable release updates policy is the reason Ubuntu 18.04 LTS does not happen to have GCC 9. But that's not the reason the build-essential, gcc, and g++ packages give you the older version of GCC--the version that was used to build the binary packages available for the system. (In 18.04 LTS, that version happens to be GCC 7.2.) The point of build-essential is to give you the tools that are recommended, and officially used, for building packages for your release, and the purpose of the gcc and g++ packages is to provide the components of GCC, including the gcc and g++ commands, that are used for that purpose.

So even when an Ubuntu release officially provides later versions of GCC than the version that is used to build the system, those packages provide the earlier version.


How do I uninstall Ubuntu from my laptop?

Turn on the computer.
Wait for the HP logo to show.
Keep tapping the Shift key until you see this screen:

Use the ↑ and ↓ keys on your keyboard (no mouse!) to navigate to Windows and you should be back up and running!

If your screen does not contain an entry for Windows, we're sorry to say but after 2 months, all your files will be lost. The only thing you can do is take the Windows Recovery Environment from the same menu which will wipe your entire PC. If you also have no recovery environment in the menu, please restore your PC with the HP Recovery DVD and then your file back-up.

If you also have no HP Recovery DVD, contact HP, they will be able to send you one (this is probably a payable service)

Alternatively
You can use this procedure to reset the Ubuntu password, which would give you access to Ubuntu itself.


After following links on the subject (a long time ago), I ended up (somehow) installing unity over gnome, which obviously messed everything up. I had to format the computer and reinstall Ubuntu. Now, it works.


It is not a good idea to just delete directories like that. And I don't know what you mean by "and so on". But it seems that the problem is with setting up your DesktopCouch, which in this case probably won't prevent you from start programming. There have been some issues with DesktopCouch lately, so unless you're experiencing other issues with your system, I would just ignore them for now.

You should also confirm that DesktopCouch is running by opening file:///home/YOUR_USERNAME/.local/share/desktop-couch/couchdb.html (remember to change to your own username). This will present you with a webpage where you can look at your databases.