up vote 0 down vote

Does not work on. you don't help people like this!

Ubuntu disable and hide digital audio output SPDIF in all Realtek / Nvidia Cards by default in fact it does same in all flavor of Ubuntu because no body cares the final user.

The prosedure to fixit is the same in all verssion of ubuntu and works for all sound cards Ati Nvidia Realtek Creative Bosse etc. You need to edit a file to do work get a terminal and tipe this

sintax: sudo nano /etc/modprobe.d/alsa-base.conf (enter)

then add this line to the end of the file

sintax: options snd-hda-intel model=auto (then use the end page controls to rewrite and save the file, then exit console)

At this time you need to reboot the machine, and then realize the missing digital audio spdif its work! go to task bar icon to select propper devise (its show now) to avoid get sound for all speackers at same time. if you need mute ubuntu alets or whatever you need to do enjoy.

for spanish take this link: http://www.fermu.com/es/articulos/linux/48-ubuntu/773-configurar-audio-hdmi-a-trav%C3%A9s-de-una-tarjeta-gr%C3%A1fica-nvidia-geforce-8600m-gt-en-ubuntu

Boggart Akerley NASA Space Ship Program Sofware Engineer.


Gitkraken depends on libgnome-keyring0 package to manage keyrings. So install libgnome-keyring0 package

sudo apt install libgnome-keyring0


KernelDriver=nvidia-current is correct if you have installed the nvidia-current package, you should not change that on Ubuntu. Since Ubuntu 12.10, you need to install the kernel headers yourself.

So, revert your KernelDriver change (the Driver= one does not matter) and install the kernel headers:

sudo apt-get install linux-headers-generic

This should automatically build the nvidia module. When this is completed, reboot or start the Bumblebee daemon:

sudo start bumblebeed

Then try running optirun glxspheres again.


ssh server service won't start on Ubuntu 18.04 after reboot

First, this proved to be one of few problems of my carrier, for which I couldn't find any solution on Google/Stack Exchange etc!!
In the end, after spending more than 2 to 3 'FULL' days on this problem and reading tens of web pages, I finally happen to solve it by accident.
When the instance was showing its display thru serial ports, I happen no note one error which showed that it was trying to mount a hard disk, which was no longer available. And on further looking, I found that because of this 'unfindable' disk, the nginx service wasn't starting (I don't know the reasons behind this). And because of this, later I found, the ssh daemon service wasn't being started (I don't know why ssh(d) service was able to start manually when I commanded it thus?!!
So, solution is, edited the file /etc/fstab and removed the auto-mounting line from it. It caused Nginx to load properly, which caused 'sshd' to start/load properly!!
And to think!!, no solution on tens of forums, happen to mention this.


Ubuntu 18.04 LTS install from USB - How to make bootable USB on Windows?

The easy way is to clone from the iso file to the USB pendrive

There is no need for uncompression. The iso file can be cloned directly as it is, each byte copied directly.

In Ubuntu 16.04 LTS and newer versions you can use the Startup Disk Creator for this purpose.
In older versions of Ubuntu and in other linux distros you can use Disks alias gnome-disks or mkusb.
In Windows you can use Win32 Disk Imager. All these tools ask for a final confirmation, which make them safer than the command line tool dd (but all of them do the job, also dd, when set correctly).

There are also extracting tools, for example

Unetbootin in linux, Windows and MacOS
Rufus in Windows (there is also a cloning mode)
mkusb can also create persistent live drives, but this is a waste of effort, if you only want to use the USB pendrive to try Ubuntu and to install Ubuntu.

See this link and links from it

You can clone from the iso file to a USB stick


Ubuntu 16.04 How to use Ethernet captive portals

This seems to be a known issue with 16.04 and Linux-unfriendly captive portals, possibly fixed since 17.10 but I'm unsure and can't test it. Meanwhile, if you can't upgrade or try with the latests Ubuntu versions, use the route command in terminal.

$ sudo route

You should see something like:

Kernel IP routing table

Destination  Gateway   Genmask        Flags  Metric  Ref Use Iface
default      10.0.2.2  0.0.0.0        UG     600     0   0   wlan0
10.0.2.2     *         255.255.248.0  U      600     0   0   wlan0
link-local   *         255.255.0.0    U      1000    0   0   wlan0

Type the gateway adress in your browser (here: 10.0.2.2), this should get you to the captive portal page. Try with different browsers if necessary.


What Bioinformatics and Computational Biology tools are available?

I did some Googling on various Debian, RHEL and Virtal Machine based Operating Systems and Research tools for computational biology and bioinformatics. A few noteworthy are summarized below:

Debian Med: a Debian operating system that is particularly well fit for the requirements for medical practice and biomedical research.

DNALinux: is a Virtual Machine with bioinformatic software preinstalled.

Bioknoppix: is a customized distribution of Knoppix Linux Live CD. It comes with applications targeted for the molecular biologist. Beside using some RAM, Bioknoppix doesn't touch the host computer (because it's a Live-CD), and is ideal for demonstrations, molecular biology students, workshops, etc.

Vigyaan: ("Vigyaan" means "Science" in hindi. But this isn't a me too Scientific Linux). Vigyaan is an electronic workbench for bioinformatics, computational biology and computational chemistry. It has been designed to meet the needs of both beginners and experts. VigyaanCD is a live Linux CD containing all the required software to boot the computer with ready to use modeling software. VigyaanCD v1.0 is based on KNOPPIX v3.7.

VLinux: is a Linux distribution and appliance for students and researchers in Bioinformatics. It is based on OpenSUSE and is built using Novell's Suse Studio.

BioSLAX: is a new live CD/DVD suite of bioinformatics tools that has been released by the resource team of the BioInformatics Center (BIC), National University of Singapore (NUS). Bootable from any PC, this CD/DVD runs the compressed SLACKWARE flavour of the LINUX operating system also known as SLAX.

Bio-Linux 6.0: is a fully featured, powerful, configurable and easy to maintain bioinformatics workstation. Bio-Linux provides more than 500 bioinformatics programs on an Ubuntu Linux 10.04 base. There is a graphical menu for bioinformatics programs, as well as easy access to the Bio-Linux bioinformatics documentation system and sample data useful for testing programs. You can also install Bio-Linux packages to handle new generation sequence data types.

My opinion as a bioinformatician is to download and run any Linux flavour that suits you. Almost all are free to download and use.In my research work, I use Ubuntu and CentOS. I will share my experience.

CentOS: If you install all libraries during setup, you  will not encounter much problems later. I have used Molecular Dynamics package AMBER and Desmond on it. It runs generally without posing much problems.

Ubuntu: Since it does not come with many libraries pre-installed, you must know where to find information about running a software on it. However, since Ubuntu is very popular among researchers, I find no reason why you should not try it. If you encounter any difficulty installing or running a software, you can post questions on specific mailing lists related to that particular software.
In Ubuntu software centre programs like Pymol, AutoDock, Unipro UGENE etc. are available. Gromacs was available earlier (I did not find it in 12.04).

I would strongly suggest you to take one time effort and install all your useful software on Ubuntu and then use Remastersys to make copies of your OS to put it on as many Desktops and Workstations you wish.

Personally, I see an immense scope in having a specialized Linux OS targeted for biology and chemistry research audience.

Hope it helps.


How do I get brightness control working on an HP 655?

I finally got my brightness feature to work.
I discovered that my device uses radeon_bl0:

ls /sys/class/backlight/

to check and then i navigated to the brightness file under radeon_bl0.
My maximum brightness was 255 of which my current settings was on and i changed the value to a much lesser value and there, it worked. Here is the code i used...

 echo 'value' > /sys/class/backlight/radeon_bl0/brightness

where 'value' is any value between 1 and 255.

Hope this helps someone else.


What's the difference between the two "Desktop Image" sections on the 14.04 releases page?

NOTE: This issue has been resolved, now, for historical purposes, this screenshot shows the initial issue that was going on.

If we dissect the links in each section, we can find that the two sections are similar, but point to different ISOs on the same server.
(The mirror you're looking at mirrors the master releases page as well, but for clarity, you should edit your question to make note that the 'link' to the download page you have is to a mirror, not the master cdimage server)

The first upper "Desktop Image" section has links to the 14.04.2 LTS ISOs, which are really just respins of the ISOs with updated kernels, updated packages, newer Hardware Enablement Stacks, etc.  You should be using the images in this section, instead of the other section.

The second lower "Desktop Image" section has the original 14.04 LTS ISOs.  It has the original kernel, original packages, original hardware enablement stack, etc. from the first 14.04 ISO.

That's the only difference on that page (but it could be displayed better).

I found out from one of the mirrors vanguards that this is by-design, however it could be improved and I had filed a ticket on Ubuntu's RT (tickets) tracker to get this made known and recommend the addition of headers for those sections to detail the individual variants, to add clarity.

The Ubuntu Mirrors team (thanks, Paul Gear for handling the ticket) has removed the second section which pointed to the 14.04 original ISOs, and they have left the 14.04.2 section there.  This is now handled, and all the mirrors should now have this change.


"localhost" not default /var/www/html/index/index.html

The default DocumentRoot for Apache is /var/www/html/ (without the index/) since Ubuntu 14.04 and /var/www/ in older Ubuntu versions.


Updated from 12.04 to 14.04, software center now saying I have no permission to download software

Open a terminal with Ctrl+Alt+T, then run the following commands:

Remove the software center and all its packages:

sudo apt-get purge software-center

Remove on hold packages (saved in temp)

sudo apt-get autoclean

Update Ubuntu packages:

sudo apt-get update

Re-install the software center

sudo apt-get install software-center

Update all application:

sudo apt-get upgrade

And then run the software center and check for errors:

 software-center


pdflatex reads .eps files saved in OS/X, but not in Ubuntu

According to section 2.16 of the TexShop documentation ("Shell escape protection"), the shell escape feature is to allow pdflatex to run other programs during compilation.  In particular, the epstopdf package you are using to convert eps to pdf is such a program (incidentally, you don't have to explicitly turn that on anymore in the latest versions of TeXLive).

I am not familiar with kile or TeXWorks, but I expect they have an option in the preferences that let's you turn on the shell escape, just as in TeXShop.  You can also explicitly compile your LaTeX file from the command line: pdflatex --shell-escape file.tex where file.tex is the name of your file.

It sounds like the reason you can typeset your file on the Mac but not Ubuntu, is either: 1) Your Mac version(s) of your TeX apps have shell escape enabled, or 2) When you make your eps file on the Mac, it additionally creates pdf versions, which are later found by your TeX app and so no conversion from eps is needed.


Is any instance/part of Windows running while Ubuntu Desktop on Wubi is running?

WUBI installs Ubuntu on a hard drive image on a Windows partition/file system. It is not a virtual machine, and windows is not in any way running when you boot that Ubuntu installation.


In order to use both signals you need to include signal.h, like this example taken from the Wikipedia page related to C signals:

#include <signal.h>
#include <stdio.h>
#include <stdlib.h>

static void catch_function(int signo) {
    puts("Interactive attention signal caught.");
}

int main(void) {
    if (signal(SIGINT, catch_function) == SIG_ERR) {
        fputs("An error occurred while setting a signal handler.\n", stderr);
        return EXIT_FAILURE;
    }
    puts("Raising the interactive attention signal.");
    if (raise(SIGINT) != 0) {
        fputs("Error raising the signal.\n", stderr);
        return EXIT_FAILURE;
    }
    puts("Exiting.");
    return 0;
}


I need to split up one file with many trajectories into individual files

I'd probably reach for csplit rather than perl: it's hard to give a precise (tested) answer since you posted a png image of your file instead of actual text, but something like

csplit -f 'coord.xyz_' -b '%d' yourfile '/^[[:space:]]*37$/' '{*}'

where

-f 'coord.xyz_' sets the output filename prefix
-b '%d' sets the output numeric suffix format to unpadded decimal digits
the regular expression /^[[:space:]]*37$/ matches 37 optionally preceded by whitespace
{*} says to repeat the previous pattern as many times as possible

Note that the regular expression could possibly be simplified based on the actual content of your file: for example, if the 37 marker is always indented by a single tab, you could reduce it to /^\t37$/.

If you want to implement something equivalent in perl (as per your tag), then based on this suggestion How can I split a text file into multiple text files? you could try

perl -ne 'open(F, ">", "coord.xyz_".++$n) if /[[:space:]]*37/; print F;' yourfile


You might have noticed degraded performance because you were upgrading the system from one distribution to another (ie; from 11.10 to 12.04). It happens at times. I would suggest you to do a clean installation of 12.04. Or if you wish to wait for a month, do a clean install of upcoming release 13.04.

But please we aware that starting from 13.04, interim releases would be supported for 9 months instead of the usual 18 months. LTS releases would continue to be supported for 3/5 years as the case may be.

If you wish to continue using 11.10 (not recommended), Canonical won't publish any further security/bug-fix updates. However, you would be able to download the ones already released. You would also be able to install other softwares for your distribution. For this you would have to make certain changes to /etc/apt/sources.list. Follow the instructions in this question:

How to install software or upgrade from an old unsupported release?

As far as PPAs are concerned, it really depends on the PPA maintainer (Google/Spotify) if they wish to maintain compatibility with EOL Distribution Releases. So, there's no guarantee that they would continue to provide further updates for 11.10 users.


I want to do a bridge between ubuntu and my ps3

Assuming your PS3 is connected to your laptop using Ethernet, do:

Click on the network icon in the top right of your screen
Click "Edit connections..."
Click "Edit..." for the appropriate connection with your PS3
Click the tab "IPv4 settings"
Under "Method", select "Shared with other computers"
Click "Save..."

Note that you may need a crossover UTP cable to make this work. Also, I would advise to undo any changes you have made to the system in your pursuit of making this work.


You cant run dpkg and need to unlock it.

Try using

sudo apt-get -f install

(This will probably tell you to run dpkg)
If not run updates with

sudo update-manager

If it does run

sudo rm /var/lib/dpkg/lock

This will unlock dpkg
Next run updates using

sudo apt-get update && sudo apt-get upgrade

Then reboot your computer

sudo reboot

After you have rebooted reopen the terminal and clean old pakages

sudo apt-get autoremove

Hopefully theses steps will also fix

runit

If not run:

sudo apt-get purge git-daemon-run

Then:

sudo dpkg -r runit


Can't change desktop background image on Ubuntu Studio 16.04 LTS

Solved!!!

I could get any background image to my desktop.

The problem was in the way I used to access the images.

The right process is:

1) Open the "Configuration Panel"

2) Go to "Desktop", "Background" Tab.

3) Into the "Folder" box, look for the folder where the image you want to use is.

4) Here was my mistake, the images will appear into the "Configuration Panel" window. Not into the "Folders" box.

5) When you see the images, from the folder you chose into the panel window, just click on the image you want to use as your desktop background.

This chosen image will appear inmediately as your new desktop background.

That's all, folks!!!


viewing everybody connected to my network

You can use netdiscover

Install with command
sudo apt-get install netdiscover

Usage is sudo netdiscover -r xxx.xxx.xxx.xxx/yy

where xxx.xxx.xxx.xxx is you network and yy is subnet.

also you can use arp-scan
Install with command
sudo apt-get install arp-scan

Usage is sudo arp-scan -local

You will be got output like this in netdiscover

Linux do not provide NetBIOS name but if you have samba installed on you PC
you can use smbtree to see win shares and mashines on local network.
Output is some thing like this


Crashed dual boot system after deleting an almost empty sdc partition

Remove these two lines from etc/fstab:

PARTUUID=40a863e7-01     /media/mystick   auto    rw,user,auto    0    0
UUID=94FD-DAE8  /boot/efi   vfat    defaults    0   1<>

Uncomment this line (REMOVE THE #):

#UUID=94FD-DAE8  /boot/efi       vfat    umask=0077      0       1

swap was on sda10, now it is sda7, comment out this line:

UUID=e60a1c4d-5f36-4b7a-a115-cf27b53e50c0 none            swap    sw              0       0

And put under it:

/dev/sda7   none   swap   sw   0   0

if that gets you in then do:

sudo update-grub
sudo update-initramfs -u

then change etc/fstab back to uuid identification of swap


I've solved the problem by removing Ubuntu dock extension.
This has helped me: Annoying dock in Ubuntu 17.10


You have to use man-pages for full of options and examples along with descriptions. I have seen -l option from the man page.

Generally we all use man-pages.

try man pgrep


Slow Samba write speeds, but SSH, FTP is fast

Try to add or modify the next socket option in your smb.conf file under [global] section:

socket options = IPTOS_LOWDELAY TCP_NODELAY SO_SNDBUF=64000 SO_RCVBUF=64000 SO_KEEPALIVE

Then restart samba services:

sudo systemctl restart nmbd smbd

Another option is compiling it from sources or downloading older version from 16.04 repository. But I couldn't confirm now if it is reliable.

I've installed default Samba 4.7.6 version from repositories onto 18.04 Virtualbox VM. It transfers files at speeds more than 70MB/s.

Config file used is:

$ cat /etc/samba/smb.conf
[global]
   workgroup = WORKGROUP
   server string = %h server (Samba, Ubuntu)
   dns proxy = no
   log file = /var/log/samba/log.%m
   max log size = 1000
   syslog = 0
   panic action = /usr/share/samba/panic-action %d
   server role = standalone server
   passdb backend = tdbsam
   obey pam restrictions = yes
   unix password sync = yes
   passwd program = /usr/bin/passwd %u
   passwd chat = *Enter\snew\s*\spassword:* %n\n *Retype\snew\s*\spassword:* %n\n *password\supdated\ssuccessfully* .

   pam password change = yes
   map to guest = bad user

   usershare allow guests = yes

[homes]
   comment = Home Directories
   browseable = no
   read only = yes
   create mask = 0700
   directory mask = 0700
   valid users = %S

[netlogon]
   comment = Network Logon Service
   path = /home/samba/netlogon
   guest ok = yes
   read only = yes

[profiles]
   comment = Users profiles
   path = /home/samba/profiles
   guest ok = no
   browseable = no
   create mask = 0600
   directory mask = 0700

[printers]
   comment = All Printers
   browseable = no
   path = /var/spool/samba
   printable = yes
   guest ok = no
   read only = yes
   create mask = 0700

[print$]
   comment = Printer Drivers
   path = /var/lib/samba/printers
   browseable = yes
   read only = yes
   guest ok = no

[guest]
  path=/srv/samba/guest
  read only = no
  guest ok = yes

I created /srv/samba/guest folder with all rights and uploaded there an iso image through guest account:

$ ls -ailh /srv/samba/guest/
total 2,0G
285916 drwxrwxrwx 2 root   root    4,0K бер 20 21:35 .
285915 drwxr-xr-x 3 root   root    4,0K бер 20 21:17 ..
264940 -rw-r--r-- 1 nobody nogroup 2,0G бер 11 16:04 ubuntu-18.04.4-desktop-amd64.iso

So this issue is not universal for all 18.04.


I'm afraid this is not the case. Some public institutions have indeed deployed Ubuntu, but that is far from being the norm. Nonetheless, you should be able to find useful information to back your arguments in Canonical's Case Studies page.


Preventing tearing / ripping noises from speaker

Speakers that have been overdriven tend to melt the glue on the voice coil, so the wires rub on the magnet - often there will be a resonant frequency + harmonics, so you will find a range of notes hit this - it really isn't practical to run an active filter all the time, but if you have a 'tone' control on the speaker it might help.
External speakers aren't expensive, I have a £10 bluetooth one from Lidl which is more than adequate for a laptop...


I google it and found a lot of similar problems, most of them with no solution. But a couple of guys managed to solve this problem by changing the SATA port connected to the CD-ROM.

https://bbs.archlinux.org/viewtopic.php?id=125686


you should open "Software and Updates", go to the "Other Software" tab, then find that line and delete it. then exit Software and sources and allow soures to reload.

after that yupdates will work  once again.


How do I install Windows alonside Ubuntu 12.04?

You can use Virtualbox and run Windows as a VM.

The VM Player is also a good solution for running Windows within Ubuntu.


How to Repair Grub while dual booting ( win7 / ubuntu 11.10)

My "Fix-Grub-routine" is as follows:

Boot from an Ubuntu LiveCD (USB key usually)
Mount the /root and /boot partition of my original install in the live environment. Lets say my root is mounted in /tmp/myRoot/ and boot in /tmp/myBoot/
Mount/bind a few important directories
sudo mount --bind /dev /tmp/myRoot/dev
sudo mount --bind /proc /tmp/myRoot/proc
sudo mount --bind /sys /tmp/myRoot/sys
sudo mount --bind /tmp/myBoot /tmp/myRoot/boot
Chroot into my original installation
sudo chroot /tmp/myRoot/
Now I'd usually do update-grub but since you messed up your bootsystem using some weird third-party application, I think it might be better to re-install grub using grub-install /dev/sda *.
When done, exit the chroot and reboot the system (without your live-media)

  Note: Replace /dev/sda with the drive you want grub to be installed on!

  Note2: Most of this information used to be on an Ubuntu wikipage called RecoveringUbuntuAfterInstallingWindows. While finding this page to link to in this post I noticed the page has had quite a change. The chrooting and stuff is not described anymore but instead a boot-repair utility is available on some live cds. I have not experience with it, but I suppose it's worth a shot.


"apt full-upgrade" returns "1 not fully installed or removed."

First, update apt to make sure the latest version matches your update list:

sudo apt update

Then, reinstall npm to replace any missing files:

sudo apt install --reinstall npm

Uninstalling packages by deleting files is dangerous. npm is for javascript, not java. If you need help uninstalling java, I strongly suggest asking a separate question for advice on how to properly uninstall.

Please post any errors, thanks.


Online Accounts, Email, and Spotify can't connect or authenticate (12.10)

I believe is was a bug in 12.10 when dealing with proxy servers... I upgraded to 13.04 and didn't have a problem.

Also, there was still the problem with thunderbird after upgrading, but switching the settings within thunderbird to use "no proxy" it worked out fine.


If that version of KDE has Network manager try opening network connections, go to the wireless tab and edit (or add) your wireless network info, making sure to check the box "available to all users." It won't ask for the wireless password again.


I found that when calling atom.exe from within wsl, the path is not interpreted correctly and defaults to atom.exe's path. In Windows, your wsl path starts with "\wsl$" which is the issue. You can use a drive map in Windows to get around this. I mapped "Z:" to "\wsl$\Ubuntu" and can open files from bash now with atom "Z:\home\user\index.html" for instance.
Further aliasing or scripting using pwd could make this less cumbersome.


ubuntu 19.04 wifi very slow - was alright for a couple of months

If the dongle and your normal wifi both fail, it's probably not your computer but your router that is not functioning properly. Try restarting your router, move closer to it, etc.

This is too general a question in my opinion so I cant provide a less general answer for you either :( Hope it helps tho :)


How to install Ubuntu 20.04 desktop alongside Windows 10 as dual boot

As I look through the different partitions listed by you, I'm sure the Windows 10 was installed using Legacy Boot Mode. You can't make UEFI dual boot in this setup unless you re-partition and install Window 10 using UEFI mode. If you don't want to touch the Windows 10 installation, you need to continue with the current partitions and install Ubuntu in Legacy Boot Mode. You selected unknowingly UEFI boot while booting from USB. Repeat the installation steps you followed using Legacy Boot Mode. You'll need to search google for the steps in doing so for the system brand and model you own. Hope this makes sense but if you need further clarification, do comment with the system brand and model number so that we may help you further.
One more thing to remember is that you need to disable 'secure boot' if it is enabled.
Good luck!


lvconvert between different volumegroups -LVM

I get the needed answer here:
https://unix.stackexchange.com/questions/515203/lvconvert-between-different-volumegroups-lvm

sudo lvcreate -L 275GB -n Wichtig Raid
sudo lvcreate -L 275GB -n Wichtig non-Raid
sudo vgcreate Wichtig /dev/Raid/Wichtig /dev/non-Raid/Wichtig
sudo lvcreate -m1 -L 250GB -n Bilder Wichtig
sudo lvcreate -m1 -l 100%FREE -n Wichtige-Daten Wichtig

Then i copied the data with dd


See how your two UUIDs are different? They should be the same. Your swap has changed.
At boot, your system reads the swap UUID in /etc/fstab and tries to mount it. But it doesn't exist, so the mounting fails. The system retries, and fails again. So the system starts looking for available swap that it can use. Eventually, your system locates the new swap partition and mounts it. That whole process takes about a full minute (or more) during boot, slowing down the boot.
Fix the problem easily by simply telling your system the correct UUID of your swap: Edit /etc/fstab and replace that old UUID with the correct UUID. You learned the correct UUID when you ran sudo blkid.
Then reboot to enjoy your faster boot.


Here's how I fixed a similar issue on my Ubuntu 18.04 machine. The system was stuck booting into an (initramfs) prompt. I have a LUKS encrypted disk as well, so I could just boot from a USB / CD and quickly repair.

I did figure it out this way though. I booted from an ancient BackTrack Linux v5 R3 DVD I had lying around. Once in a terminal, I ran fdisk -l to determine that device I was interested in is /dev/sda5.

Next, I needed to unlock the device (note that mydrive can be replaced with anything you'd like:
sudo cryptsetup luksOpen /dev/sda5 mydrive

At this point, I was prompted to enter my disk password.

And since I used the LVM on LUKS option provided by the Debian/Ubuntu installer, I need to start up LVM. So I next ran:
sudo vgchange -aly.

In my case, this device was now mapped under /dev/mapper as /dev/mapper/ubuntu--vg-root.

Now I can repair:
sudo fsck -y /dev/mapper/ubuntu--vg-root

Once it completes, remember to remove:
sudo vgchange -an /dev/mapper/ubuntu--vg

And close the device:
sudo cryptsetup luksClose mydrive

References:

https://serverfault.com/a/375095/18451
https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/4/html/Cluster_Logical_Volume_Manager/VG_activate.html


Remove files of 0 bytes in size via command line?

Use the Find command to find files by size and print file names to standard output.

find . -type f -size 0b -print

substitute -print with -delete to delete the files rather than print them on screen.

find . -type f -size 0b -delete


Convert folder with tiff to jpg by using mozjpg

You will have to build mozjpeg from source.

If you do have the packages to compile it, you can install it with the following command:

sudo apt-get install autoconf automake libtool nasm make pkg-config git

Fetch the source code with:

git clone https://github.com/mozilla/mozjpeg.git

Build it with:

cd mozjpeg
autoreconf -fiv
./configure --prefix=/usr
make

You will have 2 options: to install with the command:

make install

or to create a "deb" (that you then can use to install) with:

make deb

But it does not seem to support "tiff".  So you need to extract the files 1st. See How to convert TIFF scan file to JPEG or PNG general file format in Ubuntu? for that.

This is a generic command to compress a jpg to 75%:

convert filename1.jpg pnm:- | cjpeg -quality 75 > filename2.jpg

The jpegtran tool can be used to optimise an image:

jpegtran -outfile filename1.jpg -optimise -copy none filename2.jpg

If you get any errors please edit your question and I'll have a look.


Is it necessary fix eclipse.desktop to use Eclipse launcher in Ubuntu 16.04?

I had the same problem. Changing the eclipse.ini file as mentioned by #LuteceTheCrab seems to work only when eclipse is launched from the command prompt. However the unity launcher doesn't seem to respect the configuration in the eclipse.ini file.

Upon reading the eclipse.ini in ~/.local/share/applications directory, I realized that the Exec attribute value is set to absolute parameters.

I had to replace the value of the Exec parameter with the path of the eclipse executable.

[Desktop Entry]
Encoding=UTF-8
Version=1.0
Type=Application
Name=Java - Eclipse
Icon=eclipse.png
Path=/home/[username]/softwares/eclipse
Exec=/home/[username]/softwares/eclipse/eclipse /* <- Note this line */
StartupNotify=false
StartupWMClass=Eclipse
OnlyShowIn=Unity;
X-UnityGenerated=true

This causes the launcher to launch the executable which picks up the .ini in the same directory.

Don't put /* <- Note this line */ in the .desktop file. I have used it to highlight the line in this response.


Kernel patch that solves battery issues when for ubuntu ?

Hopefully, the patch will make it into the 3.0.0-13 kernel update for 11.10. You can help testing.

https://wiki.ubuntu.com/Kernel/PowerManagement

PS: ...and if you don't want to wait, apply the relevant workarounds now. Note, some of the workarounds are only relevant for Intel GPUs.

http://www.omgubuntu.co.uk/2011/11/linux-power-regression-overheating-problem-on-thinkpad-fixed/

Example

To add the pcie_aspm option, open /etc/default/grub for editing with  gksudo gedit /etc/default/grub

find the the GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" and change it to GRUB_CMDLINE_LINUX_DEFAULT="quiet splash pcie_aspm=force", save and exit.

Then run sudo update-grub.

You can also verify whether Active State Power Management is enabled or not with dmesg | grep -i aspm


16.04 - apt-get update 0% [Waiting for headers]

This may be old but i had a same issue and fixed it like this:

$ sudo apt-get clean
$ cd /var/lib/apt
$ sudo mv lists lists.old
$ sudo mkdir -p lists/partial
$ sudo apt-get clean
$ sudo apt-get update


Offline dictionary with pronunciation and usages

(I). dict - a CLI client to dictd server (offline usage):

Section - text

Installation:

sudo add-apt-repository "deb http://archive.ubuntu.com/ubuntu $(lsb_release -sc) universe"

(to allow Universe repo)

sudo apt-get install dict
sudo apt-get install dictd

Installing English dictionary databeses (gcide, wn, devil):

sudo apt-get install dict-gcide
sudo apt-get install dict-wn
sudo apt-get install dict-devil

Installing English Thesaurus database (moby-thesaurus):

sudo apt-get install dict-moby-thesaurus

It also supports various translation/bilingual dictionaries.

Usage:

Using a particular database (eg. WordNet - wn):

dict -d wn "dictionary"

Not specifying a dict-database will output definitions/translations/thesaurus from all available databases. eg.

dict "dictionary"

Workaround to include phoneme mnemonics:

Let's define a function that will use espeak for phoneme mnemonics and dict for definitions, thesauri, and others.

First install espeak (if it's not already):

sudo apt-get install espeak

Open the .bashrc file in your user-home directory with text editor of your choice:

nano ~/.bashrc

or

gedit ~/.bashrc &

(even better if you place your custom aliases and functions in ~/.bash_aliases rather than in ~/.bashrc)
Append the following function and save the file:

function define {
# espeak for the pronunciation audible output and phonetic alphabet string
echo "Phoneme mnemonics: $(espeak -ven-uk-rp -x -s 120 "$1" 2> /dev/null)"
# dict - the client for the dictionary server
dict "$1"
}

[here I've used the switches -ven-uk-rp for British English Received Pronunciation (espeak --voices for more), -x to display mnemonics, -s for speech output speed. You can modify the switches for espeak or dict as per your needs.]
Open a new instance of terminal and use define to look for definitions. e.g.:

define dictionary

or

define dictionary | less

(with less you can use arrow keys to scroll through the definitions; pressing h will show you some more controls that you can use; to quit press q)

  (II). Gnome Dictionary:

Section - Universe/gnome

Installation:

sudo apt-get install gnome-dictionary

Note: To use gnome-dictionary offline, you should first install a dictionary server and the desired databases (the installation of dictd and some databases are shown in option (I) above.)

After installing gnome-dictionary, a dictionary server (e.g. dictd) and the databases (e.g. dict-wn, dict-gcide) you'll have to configure so that it looks up the locally installed server. To do this, start gnome-dictionary and from the menu navigate to Edit -> Preferences. In the Dictionary Preferences window, click Add button, then in Add Dictionary Source add the information about your local dictionary server; add the Description (like dictd), the Hostname - localhost (or some other in your local network), the Port number to 2628 (2628 is the default as specified in the DICT Protocol RFC.excerpt from dictd documentation) and hit the Add button. Then in Dictionary Preferences window, select dictd radio button and close the prefs window. Now you should be able to use it offline.

  (III). "Artha", A handy off-line thesaurus based on WordNet:

Section - Universe/utils

Installation:

sudo add-apt-repository "deb http://archive.ubuntu.com/ubuntu $(lsb_release -sc) universe"

(to allow Universe repo)

sudo apt-get install artha

  (IV). "GoldenDict", offering feature-rich dictionary lookup program using WebKit for an accurate articles' representation, complete with all formatting, colors, images and links.

Section - Universe/utils

Installation:

sudo add-apt-repository "deb http://archive.ubuntu.com/ubuntu $(lsb_release -sc) universe"

(to allow Universe repo)

sudo apt-get install goldendict


When a user run crontab -e to create a personal cron job a file /var/spool/cron/crontabs/<username> is created.

Just remove the file with the same name of user who created that cron job and you're done:

sudo rm /var/spool/cron/crontabs/tweaver


Why does lsusb return my Motorola Razr D3 as "HTC (High Tech Computer Corp.)"?

According to http://www.linux-usb.org/usb.ids 0bb4 is indeed HTC. So your phone presents the ID of this manufacturer.

You would have to ask them about the why.


How to Partition my 1tb HDD into different partitions for use of dual boot plus one partition for the data?

I have never used/installed win8, so the following may not be the right way to go in your particular case.

Having said that, I just did a win7 + 8 Linux distros (Kubuntu, Trisquel, Puppy, Slitaz, Arch, Slackware, Dragora, Kali) multi boot in a laptop with 160 gb in HDD with 1 common swap partition for all Linux distros and 1 partition for data, and another install with win7 + kubuntu + Debian with 1 common swap and 2 partitions for data, 1 for Linux and 1 for win7 in a 1TB in HDD laptop

Here is what I've learned in the process:

windows needs to be in the first partition.
you only need one primary partition for windows
every other partition can be a logical partition
make a (mental) drawing/map of how your disc will look like after the partitioning process
decide how much space you will give for each partition (OS's, Data and swap)
format the Linux partitions to ext4, swap to swap and NTFS for windows (unless win8 uses a new/different file system). Find out how much space win8 requires. I have found that win7 uses 13-15 GB for a basic install, and that I need up to 30 GB for the programs that I use. So for me, 40 GB for win7 and 25 GB for Kubuntu is enough space for both OS's to live and grow. You can use the rest for data and swap. I put labels on the partitions so it is easier to know what is what later on (Linux_Data, Win_Data, My_Linux_Distro, etc.)

for the size of the swap, there are alot of different schools of thought, but I always use a swap that is the same size of my ram + a little more (say 5 MB extra, that way you can suspend your sesion to ram)

Install windows first and point to the first partition during the instalation. After that, the partition formatted to NTFS for data will be recognized automatically by windows (again, this happens with win7. Don't know if it's the same with win8).
Install your Linux distro on it's (logical partition), that is, your mounting point for / should be the partition for Linux, and if you will have only 1 Linux distro installed, you could mount /home on the data partition that you formatted to ext4.

Note: windows cannot read ext4 partitions.

To sum up: 5 partitions (1 swap, 2 ext4 and 2 NTFS), 1 primary (for win8) and the rest logical. Point the installers to the right partitions and that's about it.


sleep(int) code isn't executed in right order in C programing

sleep() is executed whenever required, but printf() doesn't print the characters immediately. It buffers the output until a newline is encountered. You should fflush(3) it. See the stdio(3) manual page for details.

If you're doing screen manipulation like this, you might want to take a look at the ncurses library rather than manually doing all this.

Also note that setting the window size only works in several terminals, and is arguable bad practice. A well written app should work with whatever reasonable window size it gets.


Lintian error: source-is-missing while building deb package for ubuntu

Lintian issues can be explained via lintian-info:

$ lintian-info -t source-is-missing
E: source-is-missing
N:
N:   The source of the following file is missing. Lintian checked a few
N:   possible paths to find the source, and do not find it.
N:
N:   Please repack your package to include the source or add it to
N:   "debian/missing-sources" directory.
N:
N:   If this is a false-positive, please report a bug against Lintian.
N:
N:   Severity: serious, Certainty: possible
N:
N:   Check: cruft, Type: source
N:

So here it complains that it can find what looks like a compiled object, but not it's corresponding source code.

In the specific case of libusb, distributing the binary without source code would be a violation of its license LGPLv2.1.

In this case, my guess would be that you should remove this embedded libusb library from the package and instead make the application use the one that is already packaged in Ubuntu.


As a final resort I disabled and then enabled my networking. This solved the problem. It appears that the connection manager can't apply the connection settings until the connection is restarted.

The user interface gives no indication that the settings are not yet applied. Which is really quite poor.


Okay, I found out of it.

I did a full apt-get purge nvidia* and apt-get dist-upgrade etc. But the thing that fixed it was actually to set the alternative correct. I guess this would've worked from the start. So here's how:

$ sudo update-alternatives --config x86_64-linux-gnu_gl_conf

  Selection    Path                                       Priority   Status
------------------------------------------------------------
  0            /usr/lib/nvidia-310/ld.so.conf              9702      auto mode
  1            /usr/lib/nvidia-310/ld.so.conf              9702      manual mode
* 2            /usr/lib/x86_64-linux-gnu/mesa/ld.so.conf   500       manual mode

As you see, for me, this setting was wrongly set. So I used 0 instead, and lo' and behold. Lots more nvidia- utilities in the PATH.

If you're not on 64-bit, then use i386 instead of x86_64.


Error when running sitespeed.io with chrome : Chrome failed to start: exited abnormally

Could it be that you have two drivers installed on different paths?

However: upgrade to latest chrome driver 2.20 and it should work with your Chrome version. You can find it here: http://chromedriver.storage.googleapis.com/2.20/chromedriver_linux64.zip


What is the UNC network path to a folder shared via Samba?

I know the IP address and netbios name of the computer, and know the shared folder path on my Ubuntu machine, but don't know how to plug that in to come up with a valid UNC path to my shared folder.

Your "shared folder path" appears to be something like /home/dan/Public. That is not your samba network path. Samba hides the internal file structure of your machine. I don't know how you created your share so look at the output of these commands:
testparm -s

net usershare info --long

Your share name will display surrounded by brackets --- and I'm guessing it's: [Public]. If this is the case your network path is:
\\ip-address\Public


How can I install a USB bluetooth dongle in Ubuntu 12.04?

You have to install drivers present in the aditional drivers in order to use USB's in virtualBox.

If your bluetooth is still not working then check addtional drivers to see if you have to install more drivers for the USB Dongle


Can Ubuntu be installed on an Apple laptop?

Yes, it is possible to do so. I have mentioned the steps required to achieve this here.


(This is assuming you are using Unity)

gnome-tweak-tool Isn't gnome-shell dependent as far as I know, you should be able to install it with sudo apt-get install gnome-tweak-tool. That said, it may be suffering from the same issues as gnome-shell.

Personally, I'd recommend you use ubuntu-tweak. It provides the same options as gnome-tweak-tool, as well as several others such as a janitor, etc. You can install it with

sudo add-apt-repository ppa:tualatrix/ppa
sudo apt-get update && sudo apt-get install ubuntu-tweak


How can I integrate updates to a installation CD/DVD?

UCK (Ubuntu Customization Kit) is a tool that helps you customizing official Ubuntu Live CDs (including Kubuntu/Xubuntu and Edubuntu)  to your needs. You can add any package to the live system like, for example, language packs, applications, etc.

You can install it via Ubuntu Software Center.

Features:

Create bootable LiveCD with predefined languages based upon an original Ubuntu/Kubuntu live CD using graphical wizard.

Build live CD with special features using scripts. It is possible to customize the root filesystem (for example install/remove packages), ISO contents (add/remove docs, change names) and initrd (add modules to boot, change boot sequence).


even if you are using the ubuntu server install, you might have the pulseaudio sound server running. This will default to surround alsa emulation which espeak isn't capable to handle.

Use: espeak -v en "Hello i am espeak" --stdout|paplay instead.


pactl module-loopback loaded every time computer is turned on

Some places come to mind where you may want to look for loading of the loopback-device:

Have a look at your /etc/pulse/default.pa or in case you have defined it for a local user in ~/.pulse/default.pa to comment out this line if present like this:

# load-module module-loopback <optional parameters>

Check with paprefs (if installed) whether we have ticked the option "Loopback audio to local speakers" in the Mulicast/RTP settings tab.
You may have made a setting like "Monitor of..." in pavucontrol.
There may be or may have been another application installed that needs the loopback module to operate (search for any possible application that may come into consideration).


Bluetooth speaker: preferred mode "High fidelity playback" (A2DP) is not getting saved

There's an option in /etc/bluetooth/audio.conf called aAutoConnect=truewhich is hashed out.

sudo nano /etc/bluetooth/audio.conf

Delete the "#" at the start of the AutoConnect=true line

I found enabling this option by removing the # and got things connecting properly with my bluetooth headset

Restart the bluetooth service for the change to take effect:

sudo service bluetooth restart


How to have script detect if terminal emulator is running in a desktop session or not?

You can use the environment variable $DISPLAY as trigger within a if condition. Usually when this variable has a value you are able to run graphical applications.

Here is a bash example:

if [[ -z $DISPLAY ]]
then
    nano
else
    gedit
fi

The operator -z will return true when the envvar $DISPLAY is empty and your script will run nano, in all other cases it will run gedit.

According to the this comment of @vurp0:

  On most modern Wayland desktops (like the default desktop in Fedora
  and Ubuntu), $DISPLAY is still set due to backwards compatibility
  (through XWayland), but for a more robust script it would be good to
  test for both $DISPLAY and $WAYLAND_DISPLAY to be sure.

I would suggest to modify the test expression in the following way:

[[ -z ${DISPLAY}${WAYLAND_DISPLAY} ]]

Thus, the values of the two variables will be concatenated into a common string, which will be processed by the operator -z.

References:

Advanced Bash-Scripting Guide: 7.   Tests
Advanced Bash-Scripting Guide: 7.1. Test Constructs
Advanced Bash-Scripting Guide: 7.3. Other Comparison Operators


Install Ubuntu Desktop from Ubuntu Mini?

If you want to get the complete Ubuntu desktop then you have to do as

sudo apt-get install ubuntu-desktop

If you would like to get only the Unity then
sudo apt-get install unity is enough .

So if you have install with ubuntu desktop command as given , then all these packages will installs in your PC .


Ubuntu 12.04 Magic Mouse connected and paired but not working

i found what was the problem

i wanted to change scrool speed like

it was explainde  here

i put hid-magicmouse  instead of hid_  and put a value of 100 for scrooll speed and found reponse in dmesg

  [ 1759.669463] hid_magicmouse: 100' invalid for parameterscroll-speed'


It was simply because I had invalid characters in the filename of the image, which the screenshot software does a poor job of conveying.


Is it possible to replace Windows on an eMMC without any external device?

I'd suggest you format the ext4 partition before you install - in case you make a mistake and the partition with the Live CD is damaged.

Then just continue to install. Of course, it's not ideal conditions, but it should work.

You might find it easier to simply make a 4GB partition and format it as fat - then use UNetBootin or similar and treat it as a standard USB stick.


Why do I have trouble downloading add-ons for Firefox?

I remember that I also had this problem on Windows when I was still using Firefox. My solution back then was removing my profile and making a new one.

In Ubuntu you can access your profiles by running the following command at the prompt: firefox -ProfileManager.


In various programs, window greys up/going nowhere (frozen/locked)

The problem here was CIFS.  We had an old Windows 2003 server which we mounted with /etc/fstab.  When it decided not to respond (or the LAN maybe) then app was locked and greyed off and the only clue came from turning on all of the columns in System Montior.

Now that server has been moved to Ubuntu - problem disappears!  So glad - this was a right pain and impossible to locate.  Hope this helps somebody, basically don't use CIFS in fstab to a Windows 2003 Server, unless you like rebooting.


Gnome extension says to change Meta.keybindings_set_custom_handler. What is this, and how do I change it

Meta.keybindings_set_custom_handler refers to the gnome3 sourcecode - this is not a "setting" in the normal sense.

It is a function in the gnome-shell sourcecode in javascript, see here

  setCustomKeybindingHandler: function(name, modes, handler) {
        if (Meta.keybindings_set_custom_handler(name, handler))
            this.allowKeybinding(name, modes);
    },

or in use, at this custom extension

function enable() {
    Meta.keybindings_set_custom_handler('switch-group', _doSwitchDesktop);
    Meta.keybindings_set_custom_handler('switch-group-backward', _doSwitchDesktop);
}

function disable() {
    Meta.keybindings_set_custom_handler('switch-group', Lang.bind(Main.wm, Main.wm._startAppSwitcher));
    Meta.keybindings_set_custom_handler('switch-group-backward', Lang.bind(Main.wm, Main.wm._startAppSwitcher));
}

If you write your own extension or rewrite an existing one, you can "set" it - if you will.


Can anyone tell me how to play ps3 games on ubuntu

I have never tried this myself but I think it's worth checking out the following links:

pcsx2

sixaxis

For ps2 and ps3, respectively. To be honest, it will work but it will not work as well as simply using the respective game consoles.


Why is my syslog telling me that my bios is broken?

Best source I found that explains this if from Redhat. It is not specific to Ubuntu but related to the kernel (we all share) and your hardware giving back wrong information to the kernel.

Exchange Redhat for Ubuntu in the text copied from the link and mind the 3 bullet points (maybe you can use that to circumvent this):

  Systems fail to boot, USB is not functional, network adapter fails to work (or possibly other symptoms) due to imperfect handling of
  BIOSes with broken IOMMU handling

  Bugzilla: #524808 and Bugzilla: #533952

  Some manufacturers ship systems with a BIOS whose handling of IOMMU
  hardware is incorrect. The BIOS is supposed to tell the operating
  system where in memory to find the IOMMU hardware, but some BIOSes do
  not do so correctly, providing a garbage location or a location which
  is valid but is not actually where the device is located. The kernel
  attempts to handle these cases, but some were still not fully handled
  in the Fedora 12 release kernel. If you have a system affected by this
  problem, the most common symptom is that the USB subsystem will fail
  to work (no USB peripherals will work), but other symptoms have
  included systems that completely fail to boot, and non-functional
  network adapters.

  There are some systems currently known to be potentially affected by
  this issue. For all of those except the HP xw4600 Workstation and the
  Dell Precision M6400, all of the following conditions must be true
  before you hit the bug:

  You must be using the 32-bit edition of Fedora 12
  You must have no memory beyond the 4GB address area (practically speaking, this means you must have around 2.5GB of physical RAM or
  less)
  Virtualization features (VT-d) must be disabled in the BIOS

  If any of the above is not the case, you should not encounter this
  issue. If you think you may be suffering from this issue, look for a
  kernel log message including something similar to:

Your BIOS is broken; DMAR reported at address fed10000 returns all ones!

  or:

Your BIOS is broken; DMAR reported at address zero!

  Please note that if you are using a system with such a broken BIOS,
  the kernel message will always appear, even if the kernel in fact
  handles your case correctly, or you have successfully worked around
  the issue. So don't worry that you still see the message once you have
  worked around the problem.

  There are several ways to work around this issue. In most cases (see
  above), installing the 64-bit edition of Fedora 12 would be enough. If
  your BIOS has an option for it, enabling virtualization features in
  the BIOS should also work around this problem. Finally, you can work
  around this issue by appending the kernel parameter iommu=soft to your
  boot configuration.

  An updated kernel package has been released to address this issue.
  Update your system as usual to receive this update, if you do not yet
  already have it. Obviously, if you are affected by the problem, you
  will need to use one of the above workarounds to first bring your
  system to a state from which you can install a fixed kernel.


Ubuntu 13.04 RAOP to Airport Express 2nd Generation doesn't work, how do I debug and get it working?

Unfortunately we do not have an Airport Express 2nd generation to test and debug this here. In case the old RAOP protocol is still recognized and supported by this device we may however be successful in streaming audio.

With my old 1st generation Airport Express I was able to reproduce the behaviour of your player stopping playback after I added a wrong port to the IP of the device.
In newer Airport Express devices it was possible to change the port the device listens to from default 5000 to any other port. That is why stream2ip >= 0.3.4 supports streaming via a port different to default 5000 (as was in 1st generation devices). You can do so by adding this port to the IP of the device:

192.168.xxx.xxx:<port>

Let me therefore suggest you find the port of your device (best from the setup programm run from Windows or MacOS) and try if adding this port to the IP line resolves the issue.

We can not however provide a solution for devices where the stream is set up to be password protected and hence needs encryption (this encryption is not open source).

We also can not support the newer RAOP2 protocol used in newer AirPlay devices as it still is not available for pulseaudio.


Can I use the Ubuntu SDK Preview in Linux Mint?

Ubuntu sdk is open source , and ubuntu and mint uses same package management system . So therectically it is possible to install ubuntu sdk in linux mint . But it is not officially supported


it appears the reason it freezes was not the cryptsetup like it looked like, but change in monitor-setup. I edited my xorg.conf file using the Ctrl+Alt+F1 and was then able to boot again.


Unity Users:
When you click on the indicator, and you see the time left on your battery, click that menu item. It should open a window that allows you to see this info:

KDE Users:
You can find this info under "Energy Information" in Kinfocenter. Note that you won't find any graphs on a system that is plugged in.


In a hybrid SSHD all SSD access is integrated with the hard drive's firmware and should not be controlled by the OS. You will be safe to just use, partition and format your 500 GB hard drive and rely on the engineers of that drive to give you optimum performance from the integrated SSD cache.

Also see Is Seagate's new "FAST Factor Boot" technology compatible with Ubuntu? for a bit more background considerations.


Ubuntu 13.10 Freeze Problem when maximizing window

This seems to be a bug in compiz: https://bugs.launchpad.net/ubuntu/+source/compiz/+bug/1244754 which will be fixed in 14.04. Here's what I do when it happens:

Switch to virtual console (ctrl + alt + F1)
Log in with your credentials
type unity --replace to restart unity
Switch back to the graphical interface by pressing ctrl + alt + F7

PS: in the bug report they mention that it's safer to maximize windows via key combination or the icon in the top left of the window.


CPU spikes to 100% when trying to watch video

Try to run top in terminal to see what process uses all your CPU. Had similar problem when was using media on external drive (NTFS) and ntfs was the problem. If it is so - just copy file from external media to your pc and wach it localy.


nvidia-settings writes xorg.conf but doesn't load settings

LOAD ONLY SOLUTION

After using the nvidia-settings GUI just as user, edit the ~/.nvidia-settings-rc user file, and remove your host name prefix from all lines, leaving just ":" to start those lines. Just use replace all (your hostname) to nothing, in most editors.

Then, optionally set the file to read only; to lock any further changes. Otherwise nvidia-settings GUI changes will add your host name back to the file.

Or you can rename the edited file, and tell nvidia-settings to use it when loading:
  nvidia-settings -l --config=/home/user/my_edited_nvidia_settings_rc

You just have to remember to set the file to read and write, to unlock your settings, so the GUI will change them again, if needed. Alas, then, you have to remove the hostnames from it again.

I use this to set a correct gamma/color (green cast) for photography editing, with Nvidia cards. My monitor settings don't do it right.

Why removing hostname works, I don't know; but it does! Now I don't have to close the auto loaded nvidia-setting dialog every time I boot up (without the "-l"), and the darn "-l" (that's an L for load only) option works; when nvidia-setting -l is loaded as a startup application.


Remap a mouse button to act as control key

I found quite useful these link tima ago...

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

http://forums.logitech.com/t5/Mice-and-Pointing-Devices/Guide-for-setup-Performance-MX-mouse-on-Linux-with-KDE/td-p/517167


Ubuntu 14.04 does not allow changing default calculator?

This seems to be a bug in unity-settings-daemon. I have filed it with them: https://bugs.launchpad.net/ubuntu/+source/unity-settings-daemon/+bug/1399132

As a workaround you can edit the settings manually with dconf Editor. To install it run sudo apt-get install dconf-tools.

You can find your custom shortcut under org.gnome.settings-daemon.plugins.media-keys.custom-keybindings and change the binding value to XF86Calculator

Refer to https://wiki.ubuntu.com/Keybindings


Accidentally deleted boot etc, lib and bin folders (Ubuntu 14.04), need help in restoring them, if possible

It is unlikely that you system is usable after removing the /lib directory, since this contains the runtime linker (e.g., /lib/x86_64-linux-gnu/ld-2.21.so).

Without this file you will not be able to run any dynamically linked binaries (which, in general, means everything).

Any attempt to restore these directories is probably going to be complex and error prone; you are far better off simply starting from scratch.  If you have data on the system that needs to be preserved, you can boot from a live CD and copy it onto another destination (e.g., a USB thumb drive or another host on your network).

If you really wanted to try to restore things, the process would probably look something like:

Boot from a live CD
Copy over enough files to get apt working (this will probably include select contents of /lib as well as all of /etc/apt)
chroot into your broken environment and use apt-get to reinstall all your packages, possibly with a command line like apt-get --reinstall install $(dpkg --get-selections | awk '{print $1}')

But even if that works, it probably won't be an exact replica of what you had before.


I don't know about efficient, but sed with a regular expression.  Make a backup of the file in case you make a typo, but perhaps something like this:

sed -i  's/"\([0-9]\+\)_\([0-9]\+\)"/\1\2/' bigcsvfile.csv

Edit: removed the g, as kos pointed out, no g is needed.


sudo apt-get update does NOT install your updates.  It only gets the list of packages available for installation.

You need to run sudo apt upgrade to actually do the installation of updated packages.  If it still does not do all the updates, then whatever is being installed pulls in some other packages than just those specific packages that need updated and you have to approve the installation step via sudo apt dist-upgrade and its prompts.


main differences between PC and a Power PC

PowerPCs dont have any special powers! :D

PowerPC is just the name for a different processor architecture (compared to x86).  PPCs were used most extensively by Apple for their Macs until 2006, when they switched to the usual Intel x86 ("General PC") architecture.

At this point, the PowerPC userbase consists mostly of people with the older Macs, and compared to any modern PC, a PowerPC is most certainly at a disadvantage when it comes to speed, graphics, etc.

  Note: This is not to imply that there is anything wrong with the PowerPC architecture; small embedded PPC processors are still used very successfully in peripherals like GPUs (eg PowerVR in the Intel CedarTrail platform), on RAID cards (eg 3ware 8xxx/9xxx), etc. Of course, that has nothing to do with Ubuntu :)


How should I make a bug report for the 20.04 server installer?

Start with the existing bug reports to make sure yours isn't a duplicate: https://bugs.launchpad.net/subiquity/+bugs

If yours is a new bug: Start with https://bugs.launchpad.net/subiquity/+filebug
You will need an Ubuntu One logon to file a new bug report or to subscribe to an existing bug report. If you don't have an Ubuntu One login, you will be prompted to create one. Be sure to use a real e-mail address that you will check.
Describe exactly how a triager or developer can reproduce the problem on their test system.
Triagers and developers may as questions via e-mail. If you don't respond, the bug report may be closed.
If you are capable of testing patches or proposed fixes, please offer. More testing often means a faster and better fix.


The README is here: http://homes.cs.washington.edu/~tom/nachos/README.

It should explain how to install everything ;)

The directions might change, but now they include these steps:

  To get started, you should:

  use ftp to fetch the nachos.tar.Z file (turning on binary mode first)
  uncompress nachos.tar.Z
  tar -xf nachos.tar
  lpr paper.ps  -- print out the paper describing nachos
  lpr doc/*.ps  -- print out the sample assignments
  cd code; make print -- print out the nachos source code
  cd code; edit Makefile.dep -- select host machine type
  cd code; make all -- compile nachos source code
  cd c++example; lpr *.ps *.h *.cc -- print out C++ primer

You won't have to use lpr -- you can print out documentation as you normally would under Ubuntu, or use evince or another program to view the .ps files.

The Wikipedia page on Nachos (or, Not Another Completely Heuristic Operating System)  may provide more context.

It mentions several successors to Nachos:

  As Nachos has not been in active development for a number of years,
  and possesses a number of recognized flaws [...], successor projects
  have been initiated. In 2004, Stanford University created Pintos, a
  Nachos-inspired system written in C and designed to run on actual x86
  hardware. In 2000, Dan Hettena at UC Berkeley ported Nachos to Java as
  Nachos 5.0j, in an effort to make Nachos more portable, more
  accessible to undergraduates, and less susceptible to subtle bugs
  [...]. Another Java-based version was created by Professor Peter
  Druschel at Rice University.


Power the laptop on with USB stick connected already. Some BIOSes don't recognize some USB drives that are connected after power on. And by the way: remember to have Ubuntu USB stick formatted as FAT32 file system, not NTFS. NTFS USB stick will boot, but will also fail to continue shortly after that.


Is there a program that can adjust display brightness according to battery percentage?

Here is a script that checks the remaining battery every minute and adjusts the brightness accordingly. However, once the battery is below 30%, it sets the brightness to 0.

#! /bin/bash

while true
do
    chargingState=$(grep "charging state:" /proc/acpi/battery/BAT0/state | awk '{print $3}')
    batteryFull=$(grep "design capacity:" /proc/acpi/battery/BAT0/info | awk '{print $3}')
    batteryRemaining=$(grep "remaining capacity:" /proc/acpi/battery/BAT0/state | awk '{print $3}')

    batteryPercentage=$((batteryRemaining * 100/batteryFull))

    if [ $chargingState == "discharging" ]
    then
        if ((batteryPercentage > 30))
        then
            xbacklight -set $batteryPercentage
        else
            xbacklight -set 0
        fi
    fi

    sleep 60
done

Copy this text to some file, say batteryBrightness.sh
Make your script executable.

chmod +x /path/to/script

Open Startup Applications, from the cog menu present at the upper right corner.

Click on Add.

Fill in all the details and click Add.

Logout and login back to check.

Note:

Change the name of the script to whatever you have named it, wherever required.
You'd need the xbacklight package installed, if you don't have it installed, install it by running the following command:

    sudo apt-get install xbacklight


Apache could not access to copied folder: 403 Access Forbidden

You have your syntax wrong. Try:

sudo chown -R <username> /var/www

or:

sudo chmod -R a+rwX /var/www

but the most correct way would be:

sudo groupadd www
sudo useradd -g <username> www
sudo chown -R :www /var/www
sudo chmod -R g+rwX /var/www
sudo chmod g+s /var/www


Listing files in a directory including contents of subfolders with sorting

You can use find:

find . -type f -printf "%s %P\n" | sort -n

Optional: To convert byte values to human-readable format, add this:

| numfmt --to=iec-i --field=1

Explanation:

 find in current directory (.) all files (-type f)

 -printf: suppress normal output and print the following:
     %s - size in bytes
     %P - path to file
     \n - new line

 | sort -n: sort the result (-n = numeric)


YouTube will not play in Firefox or Chrome on fresh 12.04 install

You can try html5 to watch youtube videos instead of flash, just type http://youtube.com/html5 and choose enter html5 trial, it uses html5 for video instead of flash player.


Getting missing dependency for compilation glib-compile-schemas

You need the header files. In Ubuntu and other Debian-based operating systems, header files are provided by -dev packages. So install libglib2.0-dev , by clicking that link or by running:

sudo apt-get update && sudo apt-get install libglib2.0-dev


Ubuntu Server 16.10 - WiFi Driver installation without internet

Earlier on, network interfaces were assigned names in an inconsistent way. If you had one interface called eth0, and added another, the first one might be called eth1 all of a sudden. What was needed was a way to give names to network interfaces that didn't depend on other interfaces being present, but depended only on the hardware connection.

This was provided with some version of systemd that was released a few years back. It was called "Predictable Network Interfaces Names" (although "Persistent" would have been a better qualification as the names are not all that easy to predict). An interface will get its name based on BIOS information, and the name won't change until you take out the interface and e.g. put it in a different hardware slot.

Your installation, at this point, suffers from Predictable Interface Names. Your wireless card had been called wlan0 for years, but now it suddenly has another name. How can you tell? Do

sudo lshw -class network

This will show a paragraph starting with "*-network" and giving all kinds of details about your wireless card (and another paragraph for your wired interface). You want to look at the "logical name". In your case, it has changed to wlp3s0.

Change the name of the interface in your configuration files from wlan0 to wlp3s0, and you're done.


Pressing f ^ ( - 1 ) on my keyboard comes out as f⁽-1) and not f^(-1), which I want (danish keymap)

As I can replicate this in my spanish layout, found the trick:

After writing the ^ symbol, press the Space bar, to disable the superscript.


How to enable visual effects (compiz) without disabling Unity?

Compiz should work by default, you may just need to install a few extra packages:

sudo apt-get install compiz-plugins* compizconfig-settings-manager

The you can search for 'compiz' in dash, then you can open 'CompizConfig Settings Manager', and use it to change the settings to what you like

see also this question.


You can select a different locale for an application from the command line by setting a couple of environment variables. First, make sure you have the appropriate language packs installed. If you can change your language (even if it requires restarting) it means you probably do. Then, on a terminal, do this (all on the same line):

LANG=fr_FR.UTF-8 LANGUAGE=fr_FR:fr firefox

This should start firefox with the french locale and everything within the app should display in french.

I know this is clunky to use and doesn't switch the entire UI over; you have to do it in an app-by-app basis. Hopefully it'll be helpful anyway.


Cannot connect MySQL Workbench to MySQL server

You have installed MySQLWorkbench as a Snap package. You want to store the database password(s) in the Gnome Passwords & Keys facility.

However, a Snap package is sandboxed; it is not by default allowed to access this service. When you choose "Store in keychain" MySQLWorkbench is blocked by AppArmor.

You need to enter a command to allow this package to access the service. The command is:

sudo snap connect mysql-workbench-community:password-manager-service :password-manager-service

I got this from the discussion at this site.


You should remove extra complexity in your interfaces file.  Something like this should work.  You don't need to add a route when both interfaces use the same gateway.

auto ens160 ens192
iface ens160 inet static
    address 10.10.0.130/16
    mtu 1500

iface ens192 inet static
    address 10.10.0.131/16
    gateway 10.10.0.1
    dns-nameservers 10.10.0.5 10.10.0.127
    mtu 1500


Why is the installation of ubuntu on HP Pavilion ZD8000 failing?

Have you reviewed this bug report:

https://answers.launchpad.net/ubuntu/+source/gnome-nettool/+question/220688

Initially I thought, compatibility issues with your laptop are unlikely since others have had good success getting it to run on a HP Pavilion ZD8000.

though not relevant, here are the instructions for md5sum checking:

You can follow the instructions at https://help.ubuntu.com/community/HowToMD5SUM to check whether your CD is corrupt. If you have a linux system running, you can use the commandline md5sum program:

dd if=/dev/cdrom bs=1 count=732766208 | md5sum

(Details at the link above)

On windows you will have to download a program to calculated the md5sum of a disk such as winMD5Sum.


I've had various things like that fail before. I'm honestly not sure if it's just a problem with the way the commands are stored or an issue with whatever limited environment these commands are run with.

Either way there are two options that have both worked for me:

Write a little bash script. It can pretty much be your command with a #!/bin/bash stanza at the top (I've broken it up to read better):

#!/bin/bash

DEV=$(xinput list | grep 'Razer' | grep -o \=[0-9]* | grep -o [0-9]*$)
/usr/bin/xinput set-button-map $DEV 3 2 1 4 5 6 7 8 1 10 11 12 13

Then just save that somewhere like ~/.mousescript and call bash ~/.mousescript as your start-up command.
Or just wrap your command in bash:

bash -c "/usr/bin/xinput set-button-map `xinput list | grep 'Razer' | grep -o \=[0-9]* | grep -o [0-9]*$` 3 2 1 4 5 6 7 8 1 10 11 12 13"


Unable to log-in using Ubuntu One Files with the Android application

Sorry for answering so late (I don't hang out on askubuntu, perhaps I should..). The issues you were having where caused by time setting of the device / time difference between the phone and the server. These have been fixed in 1.0.3.1 version (unless the user unchecks the 'Automatic' checkbox at the top of "Date & time" device settings).


Why can alphabetical file permissions contain itself up to three times

You are correct. The first set pertains to the owner, the second to the owner group, and the third to everyone else. By default, each user has their own user group. When a user creates a file, they are set as the owner and their user group is set as the owner group. Note that these are set according to effective user. Therefore, if you create something while you have elevated privileges (ex. using sudo) the owner will be the user root and the owner group will be the group root. Users can be added to user groups and ownership can be changed using chown.

Some recognition for @guiverc who posted in the comments while I was writting my answer.


How to identify 'main' ubuntu repository apps

You don't need The Force,
Look for the Source,
It's in the package's Details section, of course.
Now to ride away on a horse.
MAIN:

UNIVERSE:


How can I change my boot options from within Windows 7?

Normally you would edit the file /etc/default/grub, but since you can't run the necessary sudo update grub afterwards in windows, I suggest you change that option temporary before starting Ubuntu in GRUB.

In GRUB (hold shift while booting if it doesn't show up) you can edit the start command line and add nosplash nomodeset. You have to select the Ubuntu (Kernel..) you want to start (usually the first entry in that menu) and then press "e", that will allow you to add your parameters.

That won't survive a reboot though, that's why if it is successful you should edit the file I mentioned above and run the update command.


How to install a Canon iP4900 on Ubuntu Precise

This printer has experimental support in gutenprint.

I was able to install it regular way from localhost:631 on Arch linux after installing gutenprint.

But this drivers only have 600*600 DPI resolution for printing which gives really bad results with color prints.

There are also official drivers from Canon for Linux but this drivers have even less features (no color printing at all). I installed them by manually copying files.


Exit Desktop to Terminal in Ubuntu 19.10

sudo systemctl isolate Name (multi-user.target) in your case

  Start the unit specified on the command line and its dependencies
  and stop all others, unless they have
             IgnoreOnIsolate=yes (see systemd.unit(5)). If a unit name with no extension is given, an extension of ".target" will
             be assumed.

  This is similar to changing the runlevel in a traditional init system. The isolate command will immediately stop
             processes that are not enabled in the new unit, possibly including the graphical environment or terminal you are
             currently using.

  Note that this is allowed only on units where AllowIsolate= is enabled. See systemd.unit(5) for details.

Stolen from manpage.


Can I install/uninstall programs on a windows drive using a Ubuntu 14.04 bootable flash drive?

If I really understand your goal here you want to bypass some the administrator permissions.

Solution 1 :

You can easily install chntpw

sudo apt-get install chntpw

and simply reset the administrator password to have full system access.

Solution 2

You can emulate a windows executable on Linux using wine and playonlinux or make the installation on a windows virtual machine using virtualbox

sudo apt-get install wine playonlinux
sudo apt-get install virtualbox

then you can move the installed files to the windows partition in the respective system location and use chntpw to make the required regedit modifications.

PS :

concerning the first solution, I am aware that there is a possibility to login into the administrator account without resetting the password but I do not remember the trick. I think it is done somehow with Linux but I am not sure it might be a bootable windows cd.


use
sprintf "%4.2f"

as noted in the comment


No, you don't need nothing special.

Note that you should connect to your Ubuntu machine to access the Virtual Machine that way, not to the guest. Something like:

rdesktop localhost

should work.


How to install the software and place it on the HDD?

In Windows (and linux) it is really hard and insecure to install your programs on something different than your boot hdd/ssd. But if you mean a secondary hard drive, this is possible with some Windows programs, but AFAIK, most Linux programs cannot be installed on a secondary hard drive. Some distro's actually support installing programs on your RAM (weird, but PCLinuxOS can do that), but then you need your complete OS on your RAM and it gets deleted if your pc reboots :(


I just wiped my computer and installed 16.04 LTS and I am not able to shut it down or restart

Since the install appears to be a fresh install, you can reinstall it to the same partition in a non-destructive way that will insure the integrity of the system files.

To do this, run the Install and choose do something else for the install option.

Pick the partition where you performed the previous install.  Be sure not to check the Format box.  It will advise you that it will be deleting the old directories (/etc,/lib,/usr,/var, ...).  These are directories that have system and install files.  Your personal installed files such as /home and /usr/local/ will remain untouched.


There is a kernel bug existing for the current upgrade - see https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1813657

Meanwhile, you can set grub to default to a prior kernel, via either

How to set previous kernel as default in GRUB (Grub customizer)

or

Set "older" kernel as default grub entry


Modules aren't loading - or something even more serious is wrong

If you have a working kernel, I'd say the easiest route to success is the Etch-A-Sketch approach. Boot into the working kernel, remove the broken kernel, nuke its /lib/modules/<kernel-version> (or /lib64/) dir and when it's all dead, reinstall the kernel.

If you need to target the issue, check the logs. /var/log/kern.log should show up module loader explosions IIRC.


How can I make a compiz window rule for the terminator terminal?

If you have compiz running...You can try to create a window rule with compizconfig-settings-manager

Example:

1) Open a Terminal and type:

sudo apt-get install compizconfig-settings-manager compiz-plugins

2) Open the compizconfig-settings-manager and go to Window Management > Window Rules

3) Click to enable the Window Rules and go to the tab Size Rules, then New

4) Fill the Width and Height and click in the Plus button

5) Open the application to the rule (my case gnome-terminal) and click in the Grab button in the new window named "Edit Match". (I will match with the Window Class)

6) Now the cursor is a cross and click in the application for the rule (my case gnome-terminal)

7) To finish.. click in the Add button.

8) Now in my case when I open the gnome-terminal will be resize to 200x100.

Hope it helps.


How does the shell environment load when logging in graphically?

If you start a X11 session, the ~/.profile and similar files are not sourced.

If you want to enforce this, create a file /etc/X11/Xsession.d/95-enforce-profile with the following content:

    # This file is sourced by Xsession(5), not executed.
    # source user profile
    if test -e ~/.bash_profile
    then
        . ~/.bash_profile
    else
        [ -e ~/.profile ] && . ~/.profile
    fi


How to make a program start in terminal after some time

manpage for at

  The  at  utility shall read commands from standard input and group them
         together as an at-job, to be executed at a later time.

Example:

$ at 12:49
at> script
at> <EOT>

and at 12:49 "script" is executed (if it is executable ;) ). You can use the -m option to get a notification in your (local) mailbox.

The options you can put behind the at are many (have a look at the manpage).


Can't boot - "Waiting for Network Configuration"

Did you try to do something like this?

In /etc/init/rc-sysinit.conf replace:

start on (filesystem and static-network-up) or failsafe-boot

with:

start on (filesystem) or failsafe-boot

From Disable network configuration services during boot time


How can I install unity from recovery mode?

You probably face the problem that everything is mounted read-only in the recovery-system. Please see my answer to "Is recovery mode supposed to hang..." about how to work around that.


How to fix the window of Audience video player in Ubuntu?

Ubuntu theme doesn't work well with headerbars, so it looks weird. Try a different theme, like Adwaita or elementary.

The second screenshot shows an old version of Audience; at the time it looked like this in Ubuntu.


If you want to fill up your GUI with new widgets while your app is running, it is completely wrong to create a bunch of separate .ui files and GtkBuilders for them. It is very easy to create a single widget from withing the code.

I assume you use Python, since you've tagged your question as pygtk.

Have a look at a simple example:

from gi.repository import Gtk

and:

my_window = Gtk.Window()
my_button = Gtk.Button()
my_window.add(my_button)
my_window.show_all()

Well, it won't really work on it's own, but that's how you can create new widgets. For details on particular widgets, head to this elegant tutorial/docs: http://python-gtk-3-tutorial.readthedocs.org/


Is it possible to run Windows 10 UWP apps on Ubuntu?

Running UWP apps is possible, at least with some apps. I've successfully run the Trello UWP app (which is only available from the Microsoft Store).

First, you need to acquire the .appx file for the UWP app. One way to do this without Windows or the Microsoft Store is to use the this site:
https://store.rg-adguard.net/
Paste the Microsoft Store URL of the app into the site. For example, the Trello app's URL is:
https://www.microsoft.com/en-us/p/trello/9nblggh4xxvw
This gives you links to all of the files available through the Microsoft Store. You only need the .appx file, which may be available as multiple versions (e.g. x86 and x64).
Chrome doesn't want to download the files simply by clicking the links. This made the site feel a bit sketchy at first. In Chrome's DevTools console, Chrome says that it's not downloading the file, because the Microsoft Store URL uses http://, and the site uses https://. But since the file is coming straight from microsoft.com, it feels safe to me.
Right-clicking the link, selecting "Save link as", and choosing "Keep" allows you to download the file despite Chrome's objections.

Once you have the .appx file, you can extract it. It's just a regular zip file, so run something like unzip -d output-dir file.appx or atool -x file.appx.
The extracted files should have a directory called "app", which should have the executable and other files for the app.
For the Trello app, just running wine Trello.exe inside the "app" directory worked for me. But other applications might not work straight away, if something more complex happens during their installation.


I'd suggest to try intalling via wubi.

Load the image into virtual cd (like Daemon Tools Lite for Windows), and start Wubi.exe


how to install windows 7 in ubuntu 14.04 LTS via virtual box

Download and install corresponding Virtual Box extension pack for your Virtualbox from here.


Look in your BIOS and see if it is the first boot priority. Make sure to unplug the installation media if you haven't done so already. You might have to reinstall it if it shows up in the BIOS, but if it doesn't show up, you need a new hard drive.


How to correctly pronounce Xenial Xerus?

They are both dictionary words

xenial xerus (sound clips included here)

zee-nee-ul zeer-us

or in IPA

/ˈzi:nɪəlˈzɪərəs/


How to boot Ubuntu 14.04 CD on Toshiba m45-s165

Can you boot from USB / Removable Media in the BIOS? Some older machines can't...

If you can, use UnetBootin to write the ISO to USB and try to boot from that. Also, try another flavor, such as lubuntu or xubuntu.


Trouble with zip support in custom Python build: zipimport.ZipImportError: can't decompress data; zlib not available

Looks like you built your Python yourself and not using the default installation. You need to do these steps:

Install the zlib the newest version
Then complie python again and run a line

./configure --prefix=/root/Python-2.7.8 --with-zlib-dir=/usr/local/lib


Pointing to Cuda8 in presence of multiple Cuda installed

I have multiple installations of CUDA in /usr/local, and the default version is determined by the link cuda ->.
xxx@cudap6:~$ ll /usr/local
total 56
drwxr-xr-x 14 root   root   4096 lip  3 13:04 ./
drwxr-xr-x 16 root   root   4096 sty 28  2020 ../
drwxr-xr-x  3 root   root   4096 sie 26 18:02 bin/
lrwxrwxrwx  1 root   root      8 lip  3 13:04 cuda -> cuda-9.1/
drwxr-xr-x 16 root   root   4096 cze 15 14:35 cuda-10.2/
drwxr-xr-x 17 root   root   4096 lip  5  2018 cuda-8.0/
drwxr-xr-x  3 root   root   4096 cze 24 15:24 cuda-9.0/
drwxr-xr-x 17 root   root   4096 lut 23  2019 cuda-9.1/
drwxr-xr-x  2 root   root   4096 sie  1  2017 etc/
..

Also, In $PATH I have entry: /usr/local/cuda-9.1/bin, which is the location of nvcc. It is described here:
https://docs.nvidia.com/cuda/cuda-installation-guide-linux/index.html#post-installation-actions


Noise messages in the syslog from thermald

Version 1.4.3-5 of thermald includes a fix to stop this log smapping:

thermald (1.4.3-5~15.04.1) vivid; urgency=medium

Backport to vivid, fix debug spam in log (LP: #1494461)

See: https://bugs.launchpad.net/ubuntu/+source/thermald/+bug/1494461

So this update should have fixed this issue


How do I use LibreOffice's 3d transitions in Impress?

It appears that ogltrans still does not yet work in Ubuntu 11.10 for LibreOffice 3.44 (OOO340m1 build 402) (refer to https://launchpad.net/ubuntu/oneiric/i386/libreoffice-ogltrans/1:3.4.4-0ubuntu1). Hope this will be fixed soon so I can continue to "impress" people...

BTW, libreoffice-presenter-console also wasn't working until I updated it to 1.10 with the latest LibreOffice on 16-nov-2011.


Open the terminal and type python  (python followed by a space), then drag the ex1.py file into the terminal and press Enter. If the command executes successfully you now know two things.

ex1.py executed successfully.

When you drag a file from the file manager into the terminal it automatically prints the complete path to that file. In order to access ex1.py using cd change directories to the directory that contains ex1.py which can be identified from the path to ex1.py.


Is it possible to write a Mobile app with a engine written in C?

This should work since the SDK is based on Qt5 and QtQuick 2.0 you should be able to port (integrate) your C code because you are able to embed C code in C++. Maybe you have to write a Qt wrapper to connect the QML UI with the C backend.


how to recover ubuntu 16.04 after removing python

Log in to terminal and do apt install ubuntu-desktop, that should bring back Unity. You might be missing other packets too though.


Courier won't start because /usr/sbin/pop3d doesn't exist

Finally got it working. Posting here for posterity.

I manually copied over courier and postfix files from /usr/lib and then re-created the symlinks from /usr/sbin and /usr/bin to those files. The files were actually correctly backed-up; it's just that the ones with filesize 0 were symlinks and I checked them while my backup was still extracting.


Ubuntu VPS > restrict openerp for some user

MAC based filtering only works for machines in the same LAN. To allow or deny access to machines in remote LANs, use IP-based filtering.


Website animations not working properly in browsers

I had hardware acceleration off in Chrome. Somehow turning it on seems to have resolved this issue.


Using a GPU through USB 3.0 (for neural net training - not graphics or mining)

The comments above are correct. It works using this adapter.

You can use a GPU through a miniPCI with the adapter above. Most laptops have a spare miniPCI
You can't necessarily use a GPU through any old USB 3.0 port
You may be able to use a GPU through a USB 3.1 port. This might be called a Thunderbolt port.
Just because an adapter uses a USB 3.0 cable, doesn't mean that it is compatible with USB 3.0. It may simply be using the cable for data transfer, but not as a USB 3.0 standard protocol.

I was able to get my NVIDIA graphics card to appear with the lspci command.


Usage: [sudo] install.sh [options] standalone|zeo

You need to specify standalone or zeo.


Turns out it was a driver issue. Installing the drivers from https://github.com/hadess/rtl8723bs fixed my WiFi.


Cron doesn't check whether a previous instance was running or not, for all it knows, it simply checks the time against the conditions. You'll have to put a check in the script to prevent multiple parallel execution.


additional toolbar - one click short cuts

You could try and install Cairo Dock, this will give you a bar (at the bottom by default), which is very customisable and has options like this: .


How to prepare HDD for Windows 8 install?

By default the Windows installer creates 2 partitions, one small "System Reserved" and a big one where you install windows and where the rest of files go. You can force it to use only one partition by creating it beforehand by using for example gparted . You need to make sure that it is a ntfs primary partition.

Now if you start windows setup, point to the partition you made beforehand and it should install without partitioning anything.


MAC changes back after 30 min or earlier

You need to update the OS config for your preferred interface MAC address (hwaddress):

http://manpages.ubuntu.com/manpages/vivid/en/man5/interfaces.5.html


nginx uwsgi internal server error 500 - http uwsgi header: "Connection: close"

[SOLVED] uswgi was not able to resolve on python module.

I did the following and found the error, it may be useful to someone else for debugging.

Checked the log of uswgi:
if you don't have, set it in the .ini file where tells uwsgi to start your app:

logto = /var/log/uwsgi/%n.log

(I refer to this tutorial in case you are new: https://www.digitalocean.com/community/tutorials/how-to-serve-flask-applications-with-uwsgi-and-nginx-on-ubuntu-14-04)

Then locate your log file in the above folder, and :

tail -f myapp.log

I found that python app was not found.
After scratching my head a bit, I found the error was not in the header, but simply because I had named a backup module of my app as [name.version.py] notation (primary thing not to do in naming python modules .. uups I did it).

So it was not knowing which module to start.

As example, renamed backup as:
mv oldname.version.py newname_version.py

and works again.

However, since I uploaded the backup files to the servers while the app was working correctly, and kept on working until two days ago, I understand the server went down and restarted, then not being able to which of modules resolve: how to monitor a server restart? is it normal? As you understand, I want to configure decently despite server settings is not my business and comments for a clearer understanding on how to prevent or handle error 500 (setting alarms) are much appreciated!


Networking error - What is the first thing you want to check to find out what's wrong?

Verfication

If I cannot ping the remote device I perform the following verification in this order (depend of the error message return by the ping) :

I ensure that my wifi is not "blocked" with the command rfkill list
I check the state of my network interfaces (UP) with the command ip link
I check my IP addresses with the command ip address
I check the route of my device with the command ip route
If i'm trying to reach an hostname I check my DNS configuration (nslookup)
I ping my default gateway
If I have reach this step is that I encouter a specific problem with the computer or the error is due to an network device

Solution

If the Wifi is "hard blocked" you can use the button on your keyboard to enable the Wifi or the command rfkill unblock all
A lot of reason can Down the state of an interface. Check your wire, if it is correcly plug in, .... Then use the command sudo ip link set [INT] up
There is a lot a possible reasons for a missconfiguration of an IP address.If an DHCP server is in your LAN you can use the command sudo dhclient -v [INT] to get a automatic configuration. If this doest not work you can manually configure an IP address with sudo ip addr add 192.168.1.1/24 dev [INT]
The DHCP server can configure the routes of your device (dhclient). If that does not work you can add it manually : sudo ip route add 10.10.10.0/24 via 192.16.1.254 dev [INT]
Check the file /etc/resolv.conf. Then try to get DNS configuration from your DHCP server (dhclient). This is not recommended to configure manually the DNS configuration.

For the step 6 and 7 you need a access to your gateway/network, so basically contact your administrator.

Note : The above commands are independant of NetworkManager and will work on other Linux systems than Ubuntu.

Sorry for my english. Hope this answer will help.


Ai have problems with the installation of Ubuntu 14.04

I think you refer to the step where You have to choose a password, so you just have to write your new password.


What that page from the Dell website doesn't tell is that you have to go to System configuration / SATA Operation and switch from RAID On to AHCI.

Ubuntu will not be able to see the Dell XPS 13 SSD if you don't modify that option.

The rest of the installation procedure should proceed normally.
Also, note that the setting up of SHIMx64.EFI should be performed after the system installation, not before.


Is gcc portable between all 64 bit linux machines

If you submit the binary (I would be surprised if you had to do that) it will work (since you mentioned that the architecture of both the machines are same), most probably, unless there is a difference of the installed libraries and you actually end up using some of them.

But assuming that you just have to submit the source code, your code will be compiled on the remote server. This means that as long as you are not using some specific library present on your system, your programs will compile and run on the remote server. But if you end up using such a library, you can specify the linking flags (in your Makefile or mention it explicitly as part of your submission).


Best practice: version numbers for own packages

The field is :

debian_revision

          This part of the version number specifies  the  version  of  the
          Debian  package  based  on the upstream version.  It may contain
          only alphanumerics and the characters + . ~  (plus,  full  stop,
          tilde)  and  is compared in the same way as the upstream_version
          is.

          It is optional; if it isn’t present  then  the  upstream_version
          may not contain a hyphen.  This format represents the case where
          a piece of software was written specifically to be turned into a
          Debian  package,  and so there is only one "debianisation" of it
          and therefore no revision indication is required.

          It is conventional to restart the debian_revision  at  ’1’  each
          time time the upstream_version is increased.

          Dpkg  will  break the version number apart at the last hyphen in
          the string (if there is one) to determine  the  upstream_version
          and  debian_revision.  The absence of a debian_revision compares
          earlier  than  the  presence  of  one   (but   note   that   the
          debian_revision  is  the  least  significant part of the version
          number).

Reference


If I use EXT4 driver for EXT3 filesystem, will I get better performance? Why?

No, the ext4 driver mounts ext3 file systems using ext3 features only and performance is not affected.

See https://unix.stackexchange.com/questions/339449/mounting-ext3-file-system-using-the-ext4-subsystem-what-does-this-mean-exact for details including

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c290ea01abb7907fde602f3ba55905ef10a37477

  The functionality of ext3 is fully supported by ext4 driver. Major distributions (SUSE, RedHat) already use ext4 driver to handle ext3 filesystems for quite some time.


this should do

for i in *; do
    TESTRESULT=$(file --mime-type -b "$i");
    if [ "$TESTRESULT" == "image/jpeg" ]; then
        echo "$i";
    fi;
done

If that prints the desired files, replace echo "$i" with rm "$i"


You downloaded a file named CrashPlan_3.5.3_Linux.tar.gz file from the website and stored this somewhere on your computer. Open a termimal and go to the directory you downloaded it into and type

tar xvfz CrashPlan_3.5.3_Linux.tar.gz

This will extract the file. After it is done cd into the directory it created and install...

cd CrashPlan-install/
./install

It will then start installing CrashPlan. From their website:

  CrashPlan automatically starts up after installation and prompts you to create a new account.  Enter the information and click Create Account. CrashPlan will send backup reports and notifications to the email address you enter.

Extra: there is a README file inside the directory. Notable:

NOTES:

1) CrashPlan for Linux uses the Sun Java Runtime Environment to run.  If
you do not have the Sun Java Runtime Environment installed, CrashPlan
can download a version of the Runtime Environment and install it alongside
CrashPlan itself.  This will not overwrite your system's installed Java.

2) Once installed, the GUI can be launched by using the command 'CrashPlanDesktop',
which will be linked from your chosen directory.  If defaults are used, it
will be:

/usr/local/bin/CrashPlanDesktop

3) The background service, now called 'CrashPlan' which starts the
backup engine, will be installed and setup to run from your designated
directory. If defaults are used, it will be:

/etc/init.d/crashplan

and it will be linked from:

/etc/rc2.d

Note that on some flavors of Linux you may need to added the following to /etc/init.d/boot.local:

/etc/init.d/crashplan start


Can't boot Ubuntu 12.04 with Windows 7 installed in Toshiba Portege laptop

i think that there are two options. one is f2 to open bios. the other one is f12 which is used to temporarily override the boot order. try plugging usb before starting your pc and then hitting f12(it might also be f8). see if it shows usb hdd in the options.


While updating Ubuntu from terminal, Fetching repository list timed out

It seems that 172.0.1.201 is currently down.

Open your /etc/apt/sources.list using nano:

sudo nano /etc/apt/sources.list

and replace http://172.0.1.201/ with http://archive.ubuntu.com/.