Can Ubuntu Touch be installed on a HTC Jetstream Tablet?

No. The list of officially supported, WIP, and abandoned devices is here: https://developer.ubuntu.com/en/phone/devices/devices/


can i installl xerces 2.8 and 3.1 lib and dev, and easilly switch between them - maybe using update-alternatives?

This is what I did;

used synaptic to install xerces-2 packages
cd /usr/include
sudo cp -rp xercesc xercesc-28
used synaptic to install xerces-3 packages
cd /usr/include
sudo mv xercesc xercesc-31
sudo ln -s xercesc-31 xercesc

The above creates two key sym links; /usr/lib/libxerces-c.so, and /usr/include/xercesc. Now to configure update-alternatives to manage those two links for me;

sudo update-alternatives --install /usr/lib/libxerces-c.so libxerces /usr/lib/libxerces-c.so.28 1 --slave /usr/include/xercesc xerces-dev /usr/include/xercesc-28

sudo update-alternatives --install /usr/lib/libxerces-c.so libxerces /usr/lib/libxercesc-3.1.so 2 --slave /usr/include/xercesc xerces-dev /usr/include/xercesc-31

This allows me to select between the two libxerces alternatives, and slaves the xerces-dev selection to that choice, as well.  So, now I can switch between the two using;

sudo update-alternatives --config libxerces

update-alternatives presents a text menu, which I don't really need because I know the option numbers from the '--install' commands.  To quickly bypass that, I added these to my ~/.bashrc

alias x28='echo "1" | sudo update-alternatives --config libxerces > /dev/null'
alias x31='echo "2" | sudo update-alternatives --config libxerces > /dev/null'


If you want to compile to a .deb, have a look at this question: How do I get and modify the source code of packages installed through apt-get?

Otherwise, ./configure && make && make install is often the way to go, in the root folder of the source package.


How do I backup the whole ubuntu OS (v 16.04) inluding apps, drivers etc

Yes its possible to tell backup aka duplicity to backup certain files in certain folders.

Ass you can see there are options to chose:

Folders to save
Folders to ignore, among others

And for Ubuntu Gnome:

Its no different. And of course duplicity is intelligent enough to know what to back up so letting it do so is ok. It will do a comprehensive backup of your system and make it possible to do a restore when needed.


The update info is outdated, white triangle with exclamation sign in system tray

Second
You can re-install wine as it looks like it is the issue.
Run this at terminal: (note that this can remove your wine configuration, if you don't like this, change purge for remove):

sudo apt-get purge wine && sudo apt-get update && sudo apt-get upgrade && sudo apt-get install && sudo apt-get install wine

First
I had the same issue once. Check your sources: open a terminal and paste gksu software-properties-gtk. If you are using a server from Brasil, try another server, maybe from USA.

If you have some ppa, try to disable them at "Others Softwares" tab.


how to remove non duplicates in libreoffice calc


Remote Desktop from Windows machine using something other than Unity?

So I decided to go a little crazy and re installed the whole system with debian instead of Ubuntu and now I'm using LXDE via VNC. Problem solved.


How can I get system-wide, stay-on-the-screen Google Calendar alerts (like I get in Windows and Mac OS X)?

You may try Thunderbird. The newest version should include Lightning calendar and Provider for Google Calendar (if not you can search for these addons & install). Thunderbird gives this kind of persistent alert on a new event:

Once you have Thunderbird with Lightning and Provider for Google Calendar you may do the following:
Sync your Google account:
Go to File > New > Calendar, then select On the Network, then Google Calendar and log in and grant permission.
Install Firetray:
Go to Tools > Add-ons and search for Firetray and install it. This will keep Thunderbird running minimised in notification area, so you won't have to keep thunderbird open to get alerts for new events.
Change Notification Sound:
Go to Edit > Preferences > Calendar > Reminders (tab), make sure the checkbox next to Play a Sound is marked and then click on Browse to select the sound you want as alert.
In addition you might also want to start Thunderbird at system start-up so that you don't need to manually start it all the time.


How to get foreign dictionary without changing locale on Ubuntu Touch?

Not officaly yet. The choice of dictionary is limited to the default language keyboard layout. Unlike desktop Ubuntu where its possible to combine foreign dictictionary with english QWERTY keyboard.


Avidemux is a free video editor designed for simple cutting, filtering and encoding tasks. It supports many file types, including AVI, DVD compatible MPEG files, MP4 and ASF, using a variety of codecs.Avidemux

To install you can also click Avidemux .

Video Editing program OpenShot Features include: Support for many video, audio, and image formats (based on FFmpeg), Gnome integration (drag and drop support), and Multiple tracks.OpenShot

To install you can also click OpenShot .

Lightworks is an editing powerhouse, delivering unparalleled speed and flexibility, fully integrated with the other members of the Complete Collaboration family.Lightworks

As far as Notepad++, you can use sCiTE.  SciTE is available in apt repository of Ubuntu. To install it just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command(s) below:

sudo apt-get install scite

To convert Video, take a look at:

HandBrake is an open-source, multithreaded video transcoder- it converts digital media from one format to another, compressing the files in the process.HandBrake


Ubuntu doesn't see the free space after resizing partition

Seems like resize2fs did not get run after your partition was resized.  Some partition tools do that automatically, some dont.  Run in a terminal:
sudo resize2fs /dev/sda?

Using the sda partition number for "?".
The default is to fill the partition, and may be done on a mounted filesystem.  Neverthless, back-up anything important first, these sort of operations can go badly wrong.


how to unpack .tar file over existing directory

Okey I'll try to guide you through:

Open Nautilus and press Ctrl+H:

You will see some files and folders showing up, that were hidden before, search for a folder named .i2p and open it.
Move the netDb.tar file, from wherever you downloaded to, and place it in the opened .i2p folder.
Right click on the netDb.tar file and select Extract here.
Right click on the white background and select Open in terminal.
In the just opened terminal run chown $USER:$USER -R netDb.

How? Copy it using Ctrl+C (to avoid any typo/mistake) and paste it into the terminal with Ctrl+Shift+V, press Enter.

Done!


Just solved this issue by reinstalling blueman (bluetooth manager) and some rfkill tweak, now the bluetooth applet should be reappear:

sudo apt-get install --reinstall blueman


How to install packages libtiff4-dev and liblcms1-dev?

I installed packages.
I just changed the names of packages in requirements.apt

from libtiff4-dev
to libtiff5-dev and

from liblcms1-dev to liblcms2-dev

Because my ubuntu 16.04 don't use libtiff4-dev and liblcms1-dev


How to expand disk size with VirtualBox Ubuntu 16.04 VM

The unallocated space needs to be adjacent to the partition that you want to expand.  In this case you will need to move sda2 to the end of the disk, and then you will be able to expand sda1 to encompass the unallocated space.

You do not need to deactivate sda1 before enlarging it.  If you wanted to shrink sda1, you would need to take sda1 offline first, but since this is your Linux disk, you can't take it offline.  To do that, you would need to boot your VM from a live USB or CD, and choose 'Try Ubuntu`


What good software is available for editing RAW photo files?

Have a look at [Darktable], it's an excellent RAW editor.

sudo apt-get install darktable

(source: darktable.org)

(source: darktable.org)


find symlink to a known file /etc/init.d/ portmap

You can use find with the -l option for this.

sudo find / -mount -lname {/dir/to/file}

-mount: prevents searching on other filesystems
-l: Follow symbolic links.

Some examples I found:

How to find all symbolic links to a given file/directory?

How to find symlink


Best practices for .ssh? Should I be disabling all root login and user password access, period?

Is it safe to have the private and public key files on my local machine? Should I be deleting the public one and only holding onto the private one?

The public key can be derived from the private key (but not the other way around). How do I retrieve the public key from a SSH private key? The public key is provided merely as a matter of convenience so that you don't have to generate it every time you need to add your key to a new server.

  If I am only relying on the key, doesn't this mean I am now exposed to a new weakness: Someone getting into my machine and therefore getting access to my key file?

That's why you don't blindly press Enter when running ssh-keygen and instead use a strong password (of course, different from you user's password) to encrypt your key.

  Should I be disabling root login?

It's effectively disabled by default since the defaults only allow key-based login and root has not authorized_keys by default.

  Should I set PermitRootLogin to no or to without-password?

It's set to without-password because that's a safe default. You can set it to no if you so wish. However, if you ever need to rsync/scp as root, you'll run into trouble.

  Should I be disabling all passwords and using keys only, period? What about PasswordAuthentication and ChallengeResponseAuthentication?

If you can stick with this policy, then certainly use keys only and disable both.


Ubuntu keeps time in UTC, but Windows does it in the local time, causing conflicts.
Step 1 : Login to Ubuntu, do not change the time from settings.
Step 2: Run the below in terminal

timedatectl set-local-rtc 1 --adjust-system-clock

Step 3 : The time should have updated with the above step.
Step 4 : Reboot in windows, and back in Ubuntu and verify the problem has gone away.


How can I stop a window maximizing across two screens?

I know the way to achieve the opposite effect (force single-monitor behaviour on a dual monitor), so assuming coherence the following should work for you:

Install compizconfig-settings-manager
Open it by typing ccsm into the dash
Go to General options > display settings
Do one of the following:

If you have "Detect outputs" unchecked, check it again
If not, uncheck it, and modify the outputs in the table at the bottom so that you have one for each monitor in the format <resolution-x>x<resolution-y>+<offset-x>+<offset-y>. For example 1280x1024+0+0 and 1280x1024+1280+0 for two monitors side by side at 1280x1024

Press Alt+F2 and enter unity --replace so that compiz restarts. If compiz still refuses to apply the setting try logging out and back in

If 4.1 does not work, give 4.2 a try.


error in installing artemis in Ubuntu 14.04

The error I encountered :
error image

@N0rbert


Unable to install mesa-common-dev:i386 on my ubuntu system

You already have mesa-common-dev properly installed on your system via mesa-common-dev-lts-quantal which is a backport of the 12.10 version (9.0.3) where Ubuntu 12.04 only provides 8.0.4.

So both are not co-installable hence the conflicts at packaging level. Moreover you're trying to install a i386 package on a 64bits system.

In term of dependencies, mesa-common-dev is correctly installed, there's no need to install additional packages to set up your build environment.


The python script below does the job. Hidden files are stored separately in a folder
, as well as files without extension.

Since it might be used for a wider range of purposes, I added a few options:

You can set extensions you'd like to exclude from the "reorganization". If you simply want to move all, set exclude = ()
You can choose what to do with empty folders (remove_emptyfolders = True or False)
In case you would like to copy the files instead of moving them, replace the line:

shutil.move(subject, new_dir+"/"+name)

by:

shutil.copy(subject, new_dir+"/"+name)

The script:

#!/usr/bin/env python3

import os
import subprocess
import shutil

# --------------------------------------------------------
reorg_dir = "/path/to/directory_to_reorganize"
exclude = (".jpg") # for example
remove_emptyfolders = True
# ---------------------------------------------------------

for root, dirs, files in os.walk(reorg_dir):
    for name in files:
        subject = root+"/"+name
        if name.startswith("."):
            extension = ".hidden_files"
        elif not "." in name:
            extension = ".without_extension"
        else:
            extension = name[name.rfind("."):]
        if not extension in exclude:
            new_dir = reorg_dir+"/"+extension[1:]
            if not os.path.exists(new_dir):
                os.mkdir(new_dir)
            shutil.move(subject, new_dir+"/"+name)

def cleanup():
    filelist = []
    for root, dirs, files in os.walk(reorg_dir):
        for name in files:
            filelist.append(root+"/"+name)
    directories = [item[0] for item in os.walk(reorg_dir)]
    for dr in directories:
        matches = [item for item in filelist if dr in item]
        if len(matches) == 0:
            try:
                shutil.rmtree(dr)
            except FileNotFoundError:
                pass

if remove_emptyfolders == True:
    cleanup()

IF there is a risk of unwanted overwriting duplicate files

At the expense of a few extra lines, we can prevent overwriting possible duplicates. With the code below, duplicates will be renamed as:

duplicate_1_filename, duplicate_2_filename

etc.

The script:

#!/usr/bin/env python3

import os
import subprocess
import shutil

# --------------------------------------------------------
reorg_dir = "/path/to/directory_to_reorganize"
exclude = (".jpg") # for example
remove_emptyfolders = True
# ---------------------------------------------------------

for root, dirs, files in os.walk(reorg_dir):
    for name in files:
        subject = root+"/"+name
        if name.startswith("."):
            extension = ".hidden_files"
        elif not "." in name:
            extension = ".without_extension"
        else:
            extension = name[name.rfind("."):]
        if not extension in exclude:
            new_dir = reorg_dir+"/"+extension[1:]
            if not os.path.exists(new_dir):
                os.mkdir(new_dir)
            n = 1; name_orig = name
            while os.path.exists(new_dir+"/"+name):
                name = "duplicate_"+str(n)+"_"+name_orig
                n = n+1
            newfile = new_dir+"/"+name
            shutil.move(subject, newfile)

def cleanup():
    filelist = []
    for root, dirs, files in os.walk(reorg_dir):
        for name in files:
            filelist.append(root+"/"+name)
    directories = [item[0] for item in os.walk(reorg_dir)]
    for dr in directories:
        matches = [item for item in filelist if dr in item]
        if len(matches) == 0:
            try:
                shutil.rmtree(dr)
            except FileNotFoundError:
                pass

if remove_emptyfolders == True:
    cleanup()

EDIT

With OP in mind, we all forgot to add an instruction on how to use. Since duplicate questions might (and do) appear, it might be useful nevertheless.

How to use

Copy either one of the scripts into an empty file, save it as reorganize.py
In the head section of the script, set the targeted directory (with the files to reorganize):

reorg_dir = "/path/to/directory_to_reorganize"

(use quotes if the directory contains spaces)

possible extensions you'd like to exclude (probably none, like below):

exclude = ()

and if you'd like to remove empty folders afterwards:

remove_emptyfolders = True

Run the script with the command:

python3 /path/to/reorganize.py

NB if you'd like to copy the files instead of move, replace:

shutil.move(subject, new_dir+"/"+name)

by:

shutil.copy(subject, new_dir+"/"+name)

Please try first on a small sample.


r8168/r8169 RealTek driver module troubles

From the comments...

Using r8168-dkms 8.041.00 with the newer 4.15 kernel on Ubuntu 16.04 LTS won't work. You'll probably need 8.045.

The bionic version, r8168-dkms 8.045.08-2 from https://packages.ubuntu.com/search?keywords=r8168-dkms wouldn't compile. The cosmic -3 version would have probably worked fine.

r8168-dkms 8.045.08-3 from http://mirrors.edge.kernel.org/ubuntu/pool/universe/r/r8168/ works fine.

The system is operational now.

Note: kernel 4.15.0-24-generic has some known issues. Best to use another kernel if other problems arise.

Update #1:

r8168-dkms 8.046.00-1 has become available at http://mirrors.edge.kernel.org/ubuntu/pool/universe/r/r8168/r8168-dkms_8.046.00-1_all.deb

Update #2: (August 2019)

r8168-dkms_8.047.02-1 is now available at here.


In what order do cron jobs with the same schedule run?

The order for Ubuntu is top-down but in parallel.

Meaning, for your example:

  * * * * * /path/to/taskB
  * * * * * /path/to/taskC
  * * * * * /path/to/taskA

taskB starts first,
then taskC without waiting for taskB to complete,
then taskA without waiting for taskC or taskB to complete

Ubuntu inherits this order from Debian. But in general this behavior may vary by Linux distribution/version and cron implementation. You should not depend on it to be the same. For example, in FreeBSD, the order is bottom-up!

If the scripts depend on each other, best to call them in sequence, one from the other, or from a "master" wrapper script, which is the only one cron actually executes.


ssh connection "permission denied" message

you need to set file permissions right ,
try this ..

 $chmod go-w ~/
 $chmod 700 ~/.ssh
 $chmod 600 ~/.ssh/authorized_keys


How can non-admin users connect to Wi-Fi networks?

Your configuration is correct, but local policy files should be placed inside /etc/polkit-1/localauthority/50-local.d/ and the file extension must be .pkla.

To solve your problem:

sudo mv /etc/polkit-1/localauthority.conf.d/52-wifi-management.conf /etc/polkit-1/localauthority/50-local.d/52-wifi-management.pkla


Unity lost and login loop after installing AMD Omega 15.5 drivers

You can return your unity panels by installing CCM and turning on Unity.
Run in terminal

 sudo apt-get install compizconfig-settings-manager
 ccsm

Then check Unity checkbox.


What can I do about missing libgdk_pixbuf-2.0.la?

My fix for this was to open the files

/usr/lib/libgtkglextmm-x11-1.2.la
 /usr/lib/libgdkglextmm-x11-1.2.la

and replace any occurrences of

 /usr/lib/libgdk_pixbuf-2.0.la

with

-lgdk_pixbuf-2.0

However, the bug should now be fixed properly:

https://bugs.launchpad.net/ubuntu/+source/gtkglextmm/+bug/662572


How can I know Battery is present or absent via script?

The file /sys/class/power_supply/BAT0/status may help you.

If the battery is present it's for example:

cat /sys/class/power_supply/BAT0/status
Charging

Another place could be:

cat /proc/acpi/battery/BAT0/*

Or to view ACPI related information use the command:

acpi -i

acpi -i produces no output to the standard output when no battery is present. In a script use it as follows:

if [ -z "$(acpi -i)" ]; then
  echo "battery not present"
else
  echo "battery present"
fi


Getting crontab to change its working directory to execute a PHP script

Each of the sub expressions to && (test...,cd ... and /bin/php...) execute in different subshells, and cannot pass context (like $PWD) among themselves.

Rather than put your command in your crontab, wrap it in a simple bash script, and call that script from crontab. E.g.:
In crontab:

! test -e /var/www/html/maintenance.flag && /usr/local/bin/maint

and, in /usr/local/bin/maint:

#!/bin/bash
cd /var/www/html/shell
/bin/php ./scheduler.php --action cron --mode default"


Realtek Ethernet card disconnnects randomly

N.B :  This answer is by no means final. I've came up with a couple possible solutions based on some research online as well as personal suggestions from experience.

Replace Kernel Module

From researching online, it appears that frequently the best solution is to replace the r8168 module that comes with Ubuntu installation, with a newer , updated version. For instance, this crunchbang post.

This  Ubuntu Forums post from 2012 documents a script for a newer, updated version of the r8168 module. You can do sudo apt-get install linux-headers-$(uname -r) or     sudo apt-get install --reinstall linux-headers-$(uname -r) , and then follow matera.ttp's instructions. Praseonym, who also posted there, suggests installing the driver with dkms , which is supposed to rebuild modules for each kernel update. Now, you should have dkms already installed, and you could check it with which dkms . So you could either use Praseonym's instructions or matera.ttp's . The idea is the same.

Tweak Module Settings

For many network issues tweaking the module configurations could help solve the issues, but frankly I doubt it's an issue, since you've used  r8169 with same effect. Nonetheless , give it a try.

In  the /etc/modprobe.d/ directory, create r8168.conf file. In that file, write:

options eee_enable=1

Save and reboot.

Now, you could do very much same thing with other options. For instance, my first guess was to add options timer_count=3600 to the r8168.conf file. Why 3600 ? Assuming that the parameter deals with time, then it's most likely seconds.

I've found a case where it actually didn't work, and the problem was bios related. Refer to this page: http://ubuntuforums.org/showthread.php?t=2138125&page=2

If everything else fails

I've mentioned on other posts as well, that sometimes hardware is the issue and no matter how much tweaking you do - it won't help. In personal experience , I've dealt with two rtl8192 wireless chipsets, one of which was giving weird sound bug, but the other works almost flawlessly.

I suggest you explore possible replacements for your ethernet card. My suggestion would be portable usb hub with ethernet slot, much like these


For Gmail at least you could install it as a Chrome app and then create a launcher for it by right clicking on its icon and selecting Create Shortcuts... :

Same thing goes for any other app found in the Chrome Webstore.


Is there are any guide/documentation about byobu (Ubuntu 14.04)?

While not 14.04 specific, there is a quick-start guide available at http://j.mp/byobu-help, which does answer your "toggle all of Byobu's keybindings off" question, at least (hint: Shift-F12).

Your question here actually inspired me to write this blog post and create this 10-minute instructional video.  Enjoy!

Full disclosure: I am the author and maintainer of Byobu.


After locking + unlocking @ fastboot, getting root permissions @ android (su was missing), i was finally able to install ubuntu touch again.

When it booted to recovery, adb couldnt talk anymore to it, causing said error.
Following the order above solved it.


Ubuntu 16.04 Unity Panel Problem: Window Title Not Shown

This is some kind of temporary fix I've found.
Go to "System settings -> Appearance -> Behavior" and there in "Menus visibility" section check the option "Displayed on mouse hovering". The menus then will load only on mouse hover, and the titles will be shown.


My Postfix server became a spam server. How can I fix this?

Nuke it in orbit! Your server was compromised, I wouldn't try to "repair it" but plainly starting from 0 and then prevent it gets compromised again.

You can check our network paranoids security experts counsels at Information Security.

Related:

How do you know your server has been compromised?

Prevent from happening again:

Determining the point of compromise on an infected web server?


How to make Thunar show short file names?

Sorry, It seems Thunar does't have this functionality yet (I've exhaustively searched in Google and XFCE Documentation, there is no mentioning of this feature in official docs).

Thunar stores it's user configuration changes in ~/.config/Thunar/thunarrc file. The options currently supported are listed here. You can see, there is no settings for shortening file name. These are some advanced settings which neither support it.

I suggest you using nautilus. You can install it with sudo apt-get install nautilus.

Alternatively, You can request a feature in by going to XFCE forum to implement this or even you can help them by your coding skill, if you want.

For more information, see thunar faq or visit Official documentation for thunar.


Need link download Offline installer x11vnc for Xubuntu 18.04

I'm afraid you do not have an off-line installer, I mean, the package it self is the installer, what the apt is telling you is cannot resolve dependency by himself, as far as I know this is a common situation with .deb package and normally is fixed by run "apt -f install" command. But in your case seems you do not access to the repositories, so you have to download also libvncclient1 and libvncserver1.
The most easy solution is to let machine access internet and run apt -f install, if you can't do that here you can find each dependency and install it:

tk
libvncclient1
libvncserver1

In case more dependency will show up later you can search manually the packages in the ubuntu repos

otherwise if dependency are too many to be managed manually you can consider create a temporary repository in an usb card.


What programming languages should I learn to become an Ubuntu developer?

The answer is simple and not really helpful. Whichever language is needed. Ubuntu is a ton of software, some of it written in C, some C++, some in Python, Perl, bash... and others. You should definitely learn scripting with bash, and you should pick a language like Perl or Python, possibly the latter. Furthermore, learning good old fashioned C never hurt anyone -- you learn more about how programs work, what are libraries, lots of stuff on other tools.

Otherwise -- first find a task, a niche, something that needs to be worked on or something that is missing or something that is just fascinating and you would like to work on it. And then find out what language will be good for that purpose.


Is there any way to create a custom PS1 for particular terminal profile

There's no way to query the profile itself, but in newer gnome-terminal versions (and several other emulators) you can query the colors using commands like e.g. xtermcontrol --get-fg for the foreground, and similar options for the other colors. You can branch based on its output in .bashrc to set up different PS1.

Your gnome-terminal might be too old for this, though, since you mention you use background images which are no longer supported by recent gnome-terminal versions.


Mediterranean themes for Unity - Change input form colors

Sometimes, themes cause problems with the way text is shown in forms and dropdowns in webpages. If one simple rule doesn't work for all sites, it maybe necessary to make site-specific rules.

If one is using Firefox, open and edit /home/your_name/.mozilla/firefox/********.default/chrome/userContent.css as described here except that the actual matter to be added will depend on how the appearance of content of the web-page is to be modified.

For example:

@-moz-document domain("wolframalpha.com") {
INPUT, TEXTAREA {color: black !important; background: #aaaaaa !important; }
}

@-moz-document domain("askubuntu.com") {
INPUT, TEXTAREA {color: #aaaaaa !important; background: black !important; }
}

@-moz-document domain("google.com") {
INPUT, TEXTAREA {color: blue !important; background: tan !important; }
}

For the Chrome (or Chromium browser), the use of an extension is required. I prefer Stylish. This extension provides a GUI for making site-specific rules:

and

(Stylish is also available for Firefox!)


setup WAN miniport(PPPOE) internet connection

Try sudo pppoeconf, it will present you with a setup wizard, just accept default values and enter your username and password, it'll ask you if you want to connect at boot-time, preferably answer this with no if you don't want to be connected automatically on boot. After it is completed you can start your network connection with sudo pon dsl-provider and disconnect it with sudo poff.


I used the following blog this morning to fix all my wine programs being broken after the upgrade from 17.10.
https://linuxconfig.org/install-wine-on-ubuntu-18-04-bionic-beaver-linux
They list the following which worked for me.

wget -qO- https://dl.winehq.org/wine-builds/Release.key | sudo apt-key add -
sudo apt-add-repository 'deb http://dl.winehq.org/wine-builds/ubuntu/ artful main'


K3b is missing vcdxbuild vcdxminfo and vcdxrip, how can I install it?

You should install vcdimager package. That is all.

To install: use this command:

sudo apt-get install vcdimager


Accidentally partitioned media drive as ext3 during install (was ext4), how can I recover?

You can use the photorec program that comes in testdisk package for recovering the files. The filenames would be lost. Still the data can be recovered. If you have another big enough hard disk, create an image of this partition using dd and run photorec on the image. This would be safer. As you have created a new file system, I seriously doubt that the old journals would be still available. The backup entries might have got overwritten as well with the new journal entries. There are other data recovery tools available as well. But photorec is really easy to use and effective.


Now it works for me. I 'm going to post my solution in case someone encounters the same problem.

ppp0: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 1492 state UNKNOWN qlen 3
    inet6 2001:250:1001:2500:fc08:5666:3adb:923/64 scope global temporary dynamic
       valid_lft 258228sec preferred_lft 82394sec
    inet6 2001:250:1001:2500:d82d:cb77:2a26:f019/64 scope global dynamic
       valid_lft 258228sec preferred_lft 171828sec
    inet6 fe80::d82d:cb77:2a26:f019/10 scope link
       valid_lft forever preferred_lft forever

Two Global IPv6 address are allocated but only the global one is needed by checking the router. Hence we just delete the address.

Edit /etc/sysctl.d/10-ipv6-privacy.conf at the last line:

net.ipv6.conf.default.use_tempaddr = 2

to net.ipv6.conf.default.use_tempaddr = 0

Then restart the network.

sudo sysctl --system
sudo service network-manager restart

Done!


Why is Ubuntu 11.10 64bit using all my memory?

This is caused by Linux caching your RAM.


Can Ubuntu accept bitcoin donations? It seems to be paypal only right now

You do not have to actually have a PayPal account in order to donate using PayPal. You can use your credit/debit card to donate. After clicking the "Pay with PayPal" button, you'll get another screen. Click "Pay with your debit or credit card as a PayPal guest."
here Click "Dont have a Paypal account" option and continue.

Now, if you just hate PayPal, and refuse to use it at all, I can't help you there! :)


I had the same problem, with SAME SYSTEM today and SOLVED. It may serve for you.

If you are an expert, you can jump to the end for a 3 line solution or follow my way,

that was:
1)
$ locate crt1.o
/usr/lib/x86_64-linux-gnu/Mcrt1.o
/usr/lib/x86_64-linux-gnu/Scrt1.o
/usr/lib/x86_64-linux-gnu/crt1.o
/usr/lib/x86_64-linux-gnu/gcrt1.o
/usr/lib32/Mcrt1.o
/usr/lib32/Scrt1.o
/usr/lib32/crt1.o
/usr/lib32/gcrt1.o

As I'm using x86_64, just copied "/usr/lib/x86_64-linux-gnu/"

2)
$ locate crti.o
/usr/lib/x86_64-linux-gnu/crti.o
/usr/lib32/crti.o

It was the same as above, so, nothing new.

3a)
$ locate lgcc_s
NOTHING

panic...

But, I tried:

3b)
$ locate gcc_s
/lib/i386-linux-gnu/libgcc_s.so.1
/lib/x86_64-linux-gnu/libgcc_s.so.1
/usr/lib/gcc/x86_64-linux-gnu/4.4/libgcc_s.so
/usr/lib/gcc/x86_64-linux-gnu/4.6/libgcc_s.so
/usr/lib/gcc/x86_64-linux-gnu/4.6/libgcc_s_32.so
/usr/lib/gcc/x86_64-linux-gnu/4.6/32/libgcc_s.so
/usr/lib32/libgcc_s.so.1
/usr/libexec/autopackage/libgcc_s.so.1

Now, I just choose the older version, 4.4, so just copied "/usr/lib/gcc/x86_64-linux-gnu/4.4/"

The software in question was in a makefile. Openned the one and changed:

(from)
FFLAGS=-g -O2

(to)
FFLAGS=-g -O2 -B/usr/lib/x86_64-linux-gnu/ -B/usr/lib/gcc/x86_64-linux-gnu/4.4/

To be simple: I just add -B for each path I copied

If you are using the g77 direct in terminal, may be:

$ g77 (...) -B/usr/lib/x86_64-linux-gnu/ -B/usr/lib/gcc/x86_64-linux-gnu/4.4/ (...)

Expert:

1) Use the locate to find the path of crt1.o, crti.o and-lgcc_s (search for gcc_s);
2) Copy the paths for your distro/bits;
3) Add a "-B path_1" "-B path_2" (where path_i are the paths above) in your g77 compile call.

EDIT
cogitoergosum,  In my case, the software is VERY old and fort77, gfortran and f77 gave tons of problems. I first successfully compiled with ifort (Intel Fortran compiler). But I tried g77 for an opensource alternative. And it works!


TestDisk 7.0 doesn't have undelete option

Testdisk cannot undelete individual files from every filesystem.

The documentation states that individual files can only be undeleted from the following file system types:

  1.3  TestDisk - File recovery When a file is deleted, the list of disk clusters occupied by the file is erased, marking those sectors available for use by other files created or modified thereafter. If the file wasn’t fragmented and the clusters haven’t been reused, TestDisk can recover the deleted file for various filesystem:
  •  FAT
  •  NTFS
  •  exFAT
  •  ext2

Testdisk documentation


Depending on the version of Ubuntu you are using, the install process might be slightly different.  Please try the install process listed here: https://help.ubuntu.com/community/LikewiseOpen


Is there a way to create a hidden account?

The GUI tools ignore accounts with uid < 1000, which are reserved for system accounts.  Give the account an unused uid in that range and it won't show up in the gui tools.  Short of patching in a backdoor into the login program though, you can't hide it from the command line tools or direct inspection of /etc/passwd.


Different versions of the operating system?

The easiest way to see the operating system version is to hover over the username in the Application Launcher. I think that only main version 20.04 will appear in system settings even if the system is updated to next version 20.04.1 etc.


How to create an bootable .iso file from Ubuntu Live USB?

It should be enough to just cat the device. If your USB is, for example, /dev/sdb, you can do:

cat /dev/sdb > foo.img

to restore the image to a USB disk, do:

cat foo.img > /dev/sdb

Note that this approach will create an image file as large as the drive itself, even if the drive is almost empty. If the drive is not 100% full and you only want an iso of the used space, use genisoimage (install it with apt install genisoimage) instead:

genisoimage -o foo.iso /path/to/usb/mount/point


USB installer just exits when trying to install on a Chromebook C720

This seems related to this bug:https://bugzilla.redhat.com/show_bug.cgi?id=1135793

I'd keep an eye on that and see if they come up with any workarounds. In the meantime you could try booting Fedora 20 with mem=1024 kernel parameters and using that or try to upgrade to Fedora 21 from there with fedup.


How do I dual boot my android ice cream sandwich tablet with ubuntu

This might not be the exact solution to your problem because it installs a full desktop and not the mobile version, but this is what I had to do because my tablet isn't supported either.

Step 1: Root your tablet. Warning: This may void your warranty.

Here's some instructions for your particular tablet. (Please note that I haven't tried
these  instructions because I don't have an Archos80 Cobalt):
http://forum.xda-developers.com/showthread.php?t=2066972

Step 2: Download "Complete Linux Installer" by ZPWEBSITES from Google Play.

Step 3: Install your chosen flavor.


Multiple files as input to ffmpeg not found

Your input file names lack zero padding, so use -i picture%d.yuv.

Other stuff:

Make sure there are no missing file or breaks in your sequence.
Your output options -f mp4, -s qvga, -an, and -threads 0 are superfluous in this case.


Grub broken after upgrade to 12.04 LTS -- no keyboard, can't fix with chroot

and welcome! if you can make a copy on a CD of Super Grub Boot Disc from here...http://www.supergrubdisk.org/, you then boot up with this CD in the drive. It will find OSs and let you boot into them, them you can fix Grub by installing Grub Customizer by Daniel Richter. Good luck.


Do I need to back up my files from Windows before installing Ubuntu dual boot?

Although installing Ubuntu alongside Windows in a dual-boot configuration shouldn't, and typically doesn't, cause any data loss, it is nonetheless a very good idea for you to have a backup, at least of your documents and any other important files, that is, files you would be upset if you lost.

I'd say the three chief reasons for this are that:

There's a small risk of data loss when resizing and moving partitions and editing partition tables. This was bigger decades ago, but it's not zero today. In particular, it's likely to occur if the computer suddenly turns off during the operation, which could happen in a power failure.
There's a small risk you may make a mistake while installing Ubuntu. The installer tries to warn about operations that could cause data loss, but it gives a lot of information, and in practice people sometimes do accidentally tell it to overwrite their existing systems. (Furthermore, this risk does not drop to zero even among very experienced users.)

The popular question How do I recover my accidentally lost Windows partitions after installing Ubuntu? is probably an example of one of those (though I'm not certain which).

Far less serious than those first two situations but also more likely:

Sometimes installing Ubuntu temporarily prevents other operating systems, including Windows, from booting. This shouldn't happen and usually doesn't, but it sometimes does. This is temporary in the sense that you can fix it, and also in the sense that it's still possible to access the data, whether or not you fix it. But it's frustrating, and not being sure if you've lost data when it first happens is quite unpleasant.

Those are the reasons to have a backup--at least of your documents and other important files--when you're installing Ubuntu in a dual-boot configuration. You should, as Marcus Müller says, always have backups of your important stuff anyway, regardless of what operating system you're using. Data loss can occur at any times. Hard disks (even SSDs) don't last forever and can lose data even before they fail, and various causes ranging from malware to user error can cause files to be accidentally deleted or modified. If you already have a backup, then (a) good, and (b) I recommend making sure it's up to date before installing Ubuntu.

Once Ubuntu is installed, you should continue maintaining backups of your documents and important files, no matter where you store them. For information on some backup strategies and how to apply them in Ubuntu, see What's a good back-up strategy for 1 desktop PC?


Huwawei E173 USB dongle to user internet and send SMS (mandatory)

You can use modem-manager for sending and receiving sms from your modem.
You can install it from the software-center.
To install it from a terminal use the following command:

sudo apt-get install modem-manager-gui

Regarding mobile partner you can follow the procedure in the following link to install it.:
http://linux2help.blogspot.in/2013/10/installing-mobile-partner-in-linux.html


Help needed in evaluating disk condition

Every part of that report looks good and healthy.  It even has less than a year's worth of power-on hours on it.  It also happens to be my favorite brand.  Do you have any particular reason for being suspicious of it?


wifi-ap snap getting disabled in ubuntu core and raspberry pi 3

Have you checked the Network manager is connected to the hardware?
(I assume you are using network-manager snap as you are using wifi-ap)
You can check by

nmcli d

In case all devices are unavailable, it might be it is configured that you are using systemd-networkd.

You can configure AP on boot, you can use netplan, where you can configure in

sudo vi /etc/netplan/00-snapd-config.yaml


First, find your interface name:

hciconfig

It should give you the name of the interface, e.g., hci0.

Given that display your interface class:

hciconfig hci0 class

That should display your device class.

Finally, with super user privilege:

sudo hciconfig hci0 class 000408

should set up new class of your device.

A useful reference of bluetooth classes with hexadecimal and binary representations can be found here:
http://www.question-defense.com/tools/class-of-device-bluetooth-cod-list-in-binary-and-hex


You need two files:

Your script file:

command.sh

The .service file to be placed in /etc/systemd/system and given permission of 644 with chmod 664 command.service:

command.service

The simplest content of command.service would be:

[Unit]
Description=Some service description

[Service]
ExecStart=/bin/bash -c "/path/to/command.sh -f argument & disown"

[Install]
WantedBy=multi-user.target

Now to make it launch at boot we use the systemd controller systemctl:

sudo systemctl enable command

# or

sudo systemctl enable command.service

Note many more options are available for the various sections, see here, and make sure your command.sh is executable with chmod +x command.sh


Does installing from a persistent liveUSB also copy tools and files downloaded by user?

You can copy the files but if you install it will install the default ubuntu desktop without any additional tools or packages.

Probably the easiest way to transfer the files is to first do the install, then before you reboot, mount your fresh install and copy the files.

Assuming you install Ubuntu onto /dev/sda1

sudo -i
mount /dev/sda1 /mnt
cp your_data /mnt/home/your_new_user

Then boot your fresh install, you may need to change ownership of the files

sudo chown your_user:your_user -R ~your_user


"Leave This Page" button. Prevent from loading

This is intended behaviour for many sites which may want you to make sure that you do not leave while filling a form or similar (askubuntu.com itself uses it). In all cases I've personally encountered, I could exit with the "Leave this page" button. Are you sure that this is not a coincidence or related to another problem or program?


My problem turned out to be dhcp6
I needed change enp2s0: definition to
enp2s0:
 dhcp4: no

 dhcp6: no

 addresses: [192.168.0.10/24]


Why can't I reinstall Ubuntu Studio 16.04

There may be a problom with the ISO you burned on the install media.

Try redownlading and reburning the iso.


How can I install SQLite to be used with OpenOffice?

I think OpenOffice.org should be able to use the libsqliteodbc  ODBC driver, but I have never tried it.

Edit

Okay, I tested it and will explain how to do it...

If you click the icon above to install libsqliteodbc, make sure that you also install the AddOn “Graphical tools for ODBC management and browsing (unixodbc-bin)” (so, make sure the checkbox is ticked).

Now press Alt+F2 to launch the Run application dialog window and run ODBCConfig.  In the first tab "User DSN", press the "Add..." button.

You will get a "Select a driver..." dialog.  Select the SQLite (version 2) or SQLite3 (version 3) driver as appropriate, then press the "Ok" button.

Now you can set up the properties for the actual ODBC Data Source.  Fill in the Name field (use whatever descriptive name you want, it's there for your convenience).  Fill in the Database field (use the small > button to browse & select it).  Leave all the other fields alone.  Press the  button to save this Data Source.

After this you should see your new Data Source in the ODBC Data Source Administrator and in OpenOffice.org.

In OpenOffice.org select the option to connect to an existing database, select ODBC from the drop-down, then press "Next".  Now you should be able to select your newly-created ODBC source when you press the "Browse" button...


Ubuntu Lags on Large File Deletion or transfer

You've set vm.swappiness=1 which is TOTALLY incorrect, especially with only 8G RAM.

Set vm.swappiness=60 (based on 8G RAM and 2G SWAP), this way... (depending on your usage pattern, we may try 80 later)...

sudo -H gedit /etc/sysctl.conf # edit this file

Search for an existing vm.swappiness= entry...

CTRL+f vm.swappiness

If found, edit it to say vm.swappiness=60
If not found, add vm.swappiness=60 at the end of the file

Save your edits and quit gedit

sudo sysctl -p


extend mounted Ubuntu drive with unallocated space

You first need to grow the extended partition before it can be added to ubuntu.
Because ubuntu in in the Extended partition it can only use space inside the partition.

Also it is safest to manipulate partitions when unmounted, so booting a LiveCD to do the operations is advisable.

Boot from a LiveCD. add the free space to the extended partition.
Then add the free space inside the extended partition to  the ubuntu partition.

A second option which does not require resizing partitions is to make a partition from the free space that you mount as your home directory.
You current ubuntu partition is about 10GB. This is the amount usually given for root.

To move your /home directory:
First make a partition from the free space using gparted, and record the UUID.
mount the drive to /media, then copy the the contents of home to the new partition.
 rsync -a /home /media/(uuid of partition)
verify the copy succeed.
Rename /home ( it can be deleted later when everything is known to be working)
mv /home /homebackup

add this line to /etc/fstab
UUID=(uuid of partition) /home ext4 defaults 0 2


Well because I like mucking around with command line scripting, I've written the following. It generates a list of PPA strings that you could backup and then script into add-apt-repository:

grep -RoPish '(?<=ppa.launchpad.net/)[^/]+/[^/ ]+' /etc/apt | sort -u | sed 's/^/ppa:/'

That'll generate something like:

ppa:ubuntu-wine/ppa
ppa:am-monkeyd/nautilus-elementary-ppa
ppa:nilarimogard/webupd8
ppa:ubuntu-x-swat/x-updates
ppa:tualatrix/ppa
ppa:banshee-team/banshee-unstable
ppa:chromium-daily/beta
ppa:libreoffice/ppa
ppa:banshee-team/ppa

If you ever wanted to blanket-restore those, you could pipe them back into the system like so (assuming we saved the PPAs to ~/ppa-backup.txt:

<~/ppa-backup.txt xargs -I % sudo add-apt-repository %

I would probably suggest you don't just restore them all. Look through the backup and make sure you know what each PPA contains.


If you want a /home/ pick the option "something else" and create a mount point for / and  /home/ yourself. Don't bother with a swap partition though: we use a swapfile in Ubuntu.


How to install gnome 3 on ubuntu server?

The instructions are same as converting a normal server install to a desktop one. Gnome 3 is the default in 11.10, so you can just run the following:

sudo apt-get install ubuntu-desktop

and be done with it. If you want GNOME shell you'll need to install that too:

How do I install and use the latest version of GNOME?

Another Question reports issues with installing ubuntu-desktop on a server in 11.10.


What packages sections are available for Trusty?

Here you go:

2.4 Sections
The packages in the archive areas main, contrib and non-free are grouped further into sections to simplify handling.
The archive area and section for each package should be specified in the package's Section control record (see Section, Section 5.6.5). However, the maintainer of the Debian archive may override this selection to ensure the consistency of the Debian distribution. The Section field should be of the form:
section if the package is in the main archive area,
area/section if the package is in the contrib or non-free archive areas.
The Debian archive maintainers provide the authoritative list of sections. At present, they are: admin, cli-mono, comm, database, debug, devel, doc, editors, education, electronics, embedded, fonts, games, gnome, gnu-r, gnustep, graphics, hamradio, haskell, httpd, interpreters, introspection, java, kde, kernel, libdevel, libs, lisp, localization, mail, math, metapackages, misc, net, news, ocaml, oldlibs, otherosfs, perl, php, python, ruby, science, shells, sound, tasks, tex, text, utils, vcs, video, web, x11, xfce, zope, The additional section debian-installer contains special packages used by the installer and is not used for normal Debian packages.

So "misc".


I made a bash script to meet the objective:

flash-primary-screen.sh bash script

Copy this bash script to your computer:

#!/bin/bash

# NAME: flash-primary-screen.sh
# PATH: ~/bin
# DESC: Flashes primary screen colours to alert timer has ended.
# DATE: November 15, 2018

# NOTE: Written for: https://askubuntu.com/a/1092835/307523
#       I'm looking for a command to flash screens (if possible in colors)

# Change 6 variables below to control screen flashing levels
MaxBright="1.5"
MinBright=".5"
MaxRed="2.0"
MaxGreen="2.0"
MaxBlue="2.0"
MinGamma=".5"

declare aXrandr=()

# Next two functions lifted from: eyesome internet sunrise/sunset time screen
# brightness and gamma controller: https://github.com/WinEunuuchs2Unix/eyesome

InitXrandrArray () {

    # Array is used for each monitor and searched by name.
    # Save time to search on connected/disconnected, primary monitor,
    # brightness level, gamma level.

    mapfile -t aXrandr < <(xrandr --verbose --current)

} # InitXrandrArray

SearchXrandrArray () {

    # Parms: $MonXrandrName = xrandr monitor name to search for.

    # NOTE: Entries in array follow predicatble order from xrandr --verbose:

    #       <MONITOR-NAME> connected / disconnected (line 1 of monitor entry)
    #       Gamma:      0.99:0.99:0.99              (line 5 of entry)
    #       Brightness: 0.99                        (line 6 of entry)
    #       CRTC:       9                           (line 8 of entry)

    fNameFnd=false
    fBrightnessFnd=false
    fGammaFnd=false
    fCrtcFnd=false
    XrandrConnection=disconnected
    XrandrPrimary=false
    XrandrGamma=""
    XrandrBrightness=""
    XrandrCRTC=""           # Laptop lid open value=0, lid closed=blank

    for (( i=0; i<"${#aXrandr[*]}"; i++ )) ; do

        line="${aXrandr[$i]}"
        # Have we looped to next monitor and not found search string?
        if [[ "$line" =~ " connected " ]] && [[ $fNameFnd == true ]] ; then
            break
        fi

        if [[ "$line" =~ ^"$MonXrandrName connected" ]]; then
            fNameFnd=true
            XrandrConnection=connected
            [[ "$line" =~ "primary" ]] && XrandrPrimary=true
        fi

        if [[ $fNameFnd == true ]] && [[ $fGammaFnd == false ]] ; then
            if [[ "$line" =~ "Gamma: " ]]; then
                fGammaFnd=true
                XrandrGamma="${line##* }"
                # TODO: Use `xgamma` for accuracy
            fi
        fi

        if [[ $fGammaFnd == true ]] && [[ $fBrightnessFnd == false ]] ; then
            if [[ "$line" =~ "Brightness: " ]]; then
                fBrightnessFnd=true
                XrandrBrightness="${line##* }"
            fi
        fi

        if [[ $fBrightnessFnd == true ]] && [[ $fCrtcFnd == false ]] ; then
            if [[ "$line" =~ "CRTC: " ]]; then
                fCrtcFnd=true
                XrandrCRTC="${line##* }"
                break
            fi
        fi

    done

} # SearchXrandrArray

FlipBright () {

    if [[ $NewBrightness == "$MaxBright" ]] ; then
        NewBrightness="$MinBright"
    else
        NewBrightness="$MaxBright"
    fi

} # FlipBright

CleanUp() {

    xrandr --output "$MonXrandrName" --gamma "$SaveGamma" \
           --brightness "$SaveBrightness"

    # Compensate for bug in Xrandr as of Nov 15, 2018 with second call
    InitXrandrArray
    SearchXrandrArray
    xrandr --output "$MonXrandrName" --gamma "$XrandrGamma"
    exit 0

} # CleanUp

Main () {

    trap CleanUp INT TERM

    # Get primary monitor current settings
    XrandrName=$(xrandr --current | grep primary)
    MonXrandrName="${XrandrName%% *}"
    InitXrandrArray
    SearchXrandrArray

    # Did we find primary monitor ok?
    if [[ $fBrightnessFnd == false ]] || [[ $fGammaFnd == false ]] ; then
        echo "Internal Error: Could not find Primary Screen brightness or gamma"
        echo XrandrPrimary: "$XrandrPrimary"
        echo aXrandr[0]: "${aXrandr[0]}"
        echo Brightness: "$XrandrBrightness"
        echo Gamma: "$XrandrGamma"
        exit 2
    fi

    # Restore these values when CleanUping program
    SaveBrightness="$XrandrBrightness"
    SaveGamma="$XrandrGamma"

    # Wait for <Ctrl>+C or until parent kills us.
    while true ; do
        if [[ $Red == true ]] ; then
            Red=false
            Green=true
            NewGamma="$MaxRed:$MinGamma:$MinGamma"
            FlipBright
        elif [[ $Green == true ]] ; then
            Green=false
            NewGamma="$MinGamma:$MaxGreen:$MinGamma"
            FlipBright
        else
            Red=true
            NewGamma="$MinGamma:$MinGamma:$MaxBlue"
            FlipBright
        fi

        xrandr --output "$MonXrandrName" --gamma "$NewGamma" \
       --brightness "$NewBrightness"

        sleep .2

    done

} # Main

Main "$@"

Mark the script as executable using:

chmod a+x /path/flash-primary-screen.sh

Where /path is the directory you placed the script.

Call the script from your program (or even the command line). To end the script press Ctrl+C.

Change the first 6 variables defined to manipulate the brightness level and color level changes.

Don't hesitate to ask questions or post suggestions in comment section below!

You can also have color flashing ASCII Art text in the terminal:

Here is the script:

#!/bin/bash

From: http://wiki.bash-hackers.org/scripting/terminalcodes
DATA[0]="     _/  _/    _/                            _/    "
DATA[1]="  _/_/_/_/_/  _/_/_/      _/_/_/    _/_/_/  _/_/_/ "
DATA[2]="   _/  _/    _/    _/  _/    _/  _/_/      _/    _/"
DATA[3]="_/_/_/_/_/  _/    _/  _/    _/      _/_/  _/    _/ "
DATA[4]=" _/  _/    _/_/_/      _/_/_/  _/_/_/    _/    _/  "

# virtual coordinate system is X*Y ${#DATA} * 5

REAL_OFFSET_X=0
REAL_OFFSET_Y=0

draw_char() {
  V_COORD_X=$1
  V_COORD_Y=$2

  tput cup $((REAL_OFFSET_Y + V_COORD_Y)) $((REAL_OFFSET_X + V_COORD_X))

  printf %c ${DATA[V_COORD_Y]:V_COORD_X:1}
}

trap 'exit 1' INT TERM
trap 'tput setaf 9; tput cvvis; clear' EXIT

tput civis
clear

while :; do

for ((c=1; c <= 7; c++)); do
  tput setaf $c
  for ((x=0; x<${#DATA[0]}; x++)); do
    for ((y=0; y<=4; y++)); do
      draw_char $x $y
    done
  done
done

done

To generate the ASCII Art you can use Figlet or Toilet. See: When terminal is opened can I get current calendar and time displayed?


How to permanently set path in Ubuntu 14.04LTS

First of all, modifying your $PATH in that way is a temporary change for your current terminal session.  Other concurrent or later terminal sessions will not see that change reflected.  Add that command to your ~/.profile file if you want it to persist.

Secondly the which command is designed to search the directories in your $PATH.  If the link to "molden" is not in your $PATH or (in your case) your $PATH gets reverted, it will not find it.  See the which man page for more details.


If you are following the installation instructions from moodle.com you may have missed a small, but essemtial point.  Their command line

  cd /var/www/html/moodle sudo vim config.php

realloy should be broken into correct separate lines, as:

cd /var/www/html/moodle
sudo vim config.php

The sudo part of the second command will prompt you for your password, and grant you root privileges for the editing of the "config.php" file.  This could have been done in a single line command with

cd /var/www/html/moodle && sudo vim config.php


Ubuntu 16.04 Imagemagick convert jpg webp

Your first question can be addressed easily enough:

find . -iname '*.jpg' -exec  convert '{}' -format webp '{}'.webp \;

This will:

Recursively find all .jpg files, as in your example
Convert each .jpg file to webp using convert rather than mogrify
Use the naming convention you were after: 'filename.jpg.webp'

Tested nicely on my system...

References:

ImageMagick: Batch Processing Examples


A quick solution.

Open a terminal (Ctrl+Alt+T) and run the following commands:

For 64-bit Ubuntu (17.10 or newer):

sudo ln -s /lib/x86_64-linux-gnu/libc.so.6 /lib/libc.so.6

For 64-bit Ubuntu (before 17.10):

sudo ln -s /lib64/x86_64-linux-gnu/libc.so.6 /lib64/libc.so.6

For 32-bit Ubuntu (before 17.10):

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


Can't install Ubuntu 18.04 alongside Windows 10, no option to install alongside

I'm guessing 100% of your hard drive is configured for Windows, which is the default. You need to choose "something else", then you can use the disk manager to shrink the current Windows partition so you have available "unused" room to create an Ubuntu partition and install it in that new unused space.


Which manual do you refer to? I think that the tutorial is quite clear...

Anyway, I use Unison to sync all my machines. What I do is:

Create a profile in ~/.unison, myprofile.prf,  like this:

label = my shiny new profile
root = /home/romano/
root = ssh://romano@remotehost//home/romano/

path = education
path = research
...

(the path elements limits the subdirectories to be synced; i do not want all directories in my home to be synced by this profile, your usage can vary; if you use no path you'll duplicate everything --- be careful with hidden files though)
Then I check that the thing works ok using the graphical interface unison-gtk --- from there you can check if the operation is going to be ok):

Once you are confident that the sync will not eat your data for breakfast, you can use on the command line

unison -auto -batch myprofile


Is there any way to restore the distribution name?

I found my answer.

According to a site an user linked to me, the command dpkg -S os-release showed:

diversion by bunsen-os-release from: /etc/os-release
diversion by bunsen-os-release to: /etc/os-release.bunsen-orig

Inside the os-release.bunsen-orig is the original os-release file. I also noticed that the os-release is just a simlink to os-release.bunsen and the os-release.bunsen-orig is the simlink to the "very" original os-release file which was in /usr/lib/os-release. Since I am too lazy to figure out how to make simlinks I simply copied the os-release.bunsen-orig to os-release.


HP-Envy 4500 All-in-one printer appears to lose wireless connection

I don't know if it helps, but I have the same printer with no problem at all. It's connected to a B/G wifi router, using WPA2 encription.

The only important thing I had to do is preallocate the IP number of the printer in the router static DHCP configuration, so that it would not change across reconnections.

This thing is different from router to router, so you have to find it on your device  --- this is the screenshot for my router:


Try LinuxRespin/Remastersys.
It can be used to create live bootable ISO from your current installation of Ubuntu/Debian.


Workspace stays fixed on external monitor, Ubuntu 14.04

This worked for me:

gsettings set org.gnome.shell.overrides workspaces-only-on-primary false


Possible to add bookmarks in Nemo (Cinnamon)?

You can go to Bookmarks → Add Bookmark or use the Ctrl+D keyboard shortcut.


I have not tried it, but you can install netbook-launcher-efl, which should look like this:

I don't know if the package still exists on Natty, but in Maverick it does.


How can DejaDup backup folders requiring root permissions?

It's fine to include such directories in a backup as long as your user can READ the files (users can often, but not always, read root-owned files).

But if your user can't read the files, I recommend running duplicity directly via cron. Deja Dup is designed for users, not system administrators.


Create the directory yourself?

mkdir --mode=0700 --parents /home/xyzzy/.config/whipper

or check the existing directory's ownership and permissions with

ls -ld /home/xyzzy/.config/whipper /home/xyzzy/.config/whipper/wipper.conf

And ensure xyzzy has write access.


No control over screen brightness on Ubuntu-Mate 16.04

Open /etc/default/grub with:

sudo nano /etc/default/grub

Modify the line reading GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

so it says

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=native"

Then run:

sudo update-grub


How do I display more than 5 bookmarks in gnome-panel "Places" menu?

Is that really the only option if I want to see more than 5 bookmarks in the "Places" menu?

Yes. I'm suffering the same issue. I've posted bugs on Launchpad (marked a dupe of this one) and Gnome's Trac. I there are multiple BrainStorm threads too.

There are two elegant solutions:

Look at the resolution when gnome-panel loads, work out some render geometry based on the current theme and set a soft limit
Just use a gconf key-value to have a user-alterable number.

But both solutions require somebody to code them, somebody to accept one patch and then somebody to repackage the new version for Ubuntu... In short, it's a change that isn't going to happen soon (unless somebody steps up and gets something pushed in as a Papercut for Maverick - might be too late even for that)

Manually patching the code to have a higher fixed limit is a pain in the bottom but it does fix the problem and (in fairness) doesn't take all day to do. Just make sure you lock the version of your gnome-panel package so updates don't wipe your changes.

I'll go and poke people upstream and see if anything can be done about this.


How can I install Ubuntu on a MacBook Air?

Yes. You can install Ubuntu on a Mac Air, you can also dual boot. There's a lot of information out there, but some good Ubuntu sites already cover what you want:

I recomend reading this two:

https://help.ubuntu.com/community/How%20to%20install%20Ubuntu%20on%20MacBook%20using%20USB%20Stick

https://help.ubuntu.com/community/How%20to%20install%20Ubuntu%20on%20MacBook%20Air%20using%20live%20CD


How to change a dconf setting for customized Live CD?

To change the default for any DConf key setting, create a file in /usr/share/glib-2.0/schemas/. The filename should end in .gschema.override, but you are free to choose what to call it. You will need administrative privileges, of course.

The override file has the following syntax. You can include multiple paths in one file, and multiple key changes under each path header.

[org.gnome.desktop.session]      # Path with defaults you want to change
idle-delay=42                    # Key with default value set to '42'

Then jump to a command line (Ctrl-Alt-T) and run:

glib-compile-schemas /usr/share/glib-2.0/schemas/

References

System Defaults in GSettings — Ross Burton


How to have "File, Edit, View, ..." menu integrated in windows

Hit the Super key to open the Dash and search for "Appearance". Once the window opens, go to "Behavior" followed by "Show the menus for a window" and select the "In the window's title bar" radio button.


The reason Apache fails to start is because something is already listening on the port/ip combination.  The log entries of "Address already in use" indicate this.

You need to identify what other service is running on those ports and then go and shut it off before turning on Apache.

However, since your log snippets ONLY are partial (and not from sudo systemctl -l status apache2 so we can see all the actual useful information in large form, or from /var/log/apache2/error.log directly), we can't really point you at which application(s) to look at since we can't determine the ports in use (my assumption is Port 80, in which case sudo ss -ntlp 'sport = 80' will get us a better idea of what is already listening on Port 80.  Please replace '80' with whatever other port is actually in use according to the long log data, which is cut off in what you pasted here.)


sudo apt-get install ubuntu-desktop, Error: unable to locate package

The most likely situation is that you need to update your sources for some reason,  with

sudo apt-get update

It's also possible that your sources aren't set up correctly.  You can configure them in the update manager.  They are located in the file /etc/apt/sources.list - if you continue to have problems paste the source of that file here.


Everyone means everyone that is able to visit your system from walking up to the machine to anyone outside on the internet visiting a website you host, or ssh tunnel you set up to your system. Or abuse a backdoor in your router (Netgear, NMX300 1.5.0.11 as an example).

The way to revoke it is by executing the same command with less privileges. In general "750" for directories and "640" for files can be enough. You can combine the "chmod" with a "find" so you can alter these settings based on if it is a file or a directory.

You issue these 2 commands from the directory where you need to change anything below that directory:

find . -type f -exec chmod 640 {} \;
find . -type d -exec chmod 750 {} \;

(-type f is for files, type d is for directories)


I just did a test conversion from 16.04 to 18.04 and did not have this problem. But you can suppress Plymouth by using sudo powers to edit the file /etc/default/grub.

sudo -H gedit /etc/default/grub

Look for the line containing:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

and remove the word splash (which causes Plymouth to load).

Then save your file and run

sudo update-grub

Now Plymouth will no longer run on boot. This is a band-aid fix and you should keep searching for a real fix.


Ubuntu tweak does not start (Gtk-WARNING **: Locale not supported by C library)

first:

sudo apt-get purge locales

then:

sudo aptitude install locales

and the famous:

sudo dpkg-reconfigure locales

This rids the system of locales, then re-installs locales and downgrades libc6 from 2.19 to 2.13 which is the issue. Then configures locales again.


What you want to know is How to enable TRIM?

Which is fairly easy, simply open your terminal, open the fstab file and add the discard option to the SSD UUID that corresponds to your Samsung SSD. Basically open the terminal and:

blkid

which should show you all HDD/SSD so you can see which one is which:

Here my SSD is sdb which is the one that has the root filesystem with it (the little / you see there at the end of the line that starts with sdb1). I then:

sudo nano /etc/fstab

And look for the root filesystem (The / "slash") marked with the Red circle. I then add the discard option (marked with the blue circle) to the several options shown there. In my case it reads discard,noatime,errors.... since I only needed to add the discard and a comma. Note that the discard is AFTER the ext4, this is because each section or columns is for an specific part of fstab. The 3rd column is for the filesystem type, which is ext4 in this case. The 4th column is for the options, which is were discard is.

Now save the file by pressing CTRL+X which will show you a message below saying if you want to save the file, press Y and you are done. Now reboot the computer and you are ready.

Some benchmarks for that particular SSD will help you enjoy that fast drive:

NOTE: Gnome Disk has a problem with this SSD when doing a benchmark with Write enable. It is a bug that they are working to fix.


Why laravel api.php routes give a 404 error?

This can be resolved from apache, if you enable mod_rewrite option. So you need to run

sudo a2enmod rewrite

Changes in the file /etc/apache2/apache2.conf

<Directory /var/www/>
    Options Indexes FollowSymLinks
    AllowOverride All
    Require all granted
</Directory>

Restart apache:

sudo service apache2 restart


Ubuntu 14.04 not showing login info - motd

Have a look into manual pages for sshd_config(5). There is option PrintMotd, which makes sshd print this message of the day.

But make sure the MOTD is available in the correct path /etc/motd, correctly updated if you want to have it dynamic and that you restart your ssh service after the changes.


To figure out which device you just connected, you will get some good hints from running dmesg.

Try:

dmesg | tail

And look for something like this:

[ 7445.572614] usb 2-1.2: new high-speed USB device number 4 using ehci_hcd
[ 7445.710242] Initializing USB Mass Storage driver...
[ 7445.710746] scsi6 : usb-storage 2-1.2:1.0
[ 7445.710971] usbcore: registered new interface driver usb-storage
[ 7445.710978] USB Mass Storage support registered.
[ 7446.707999] scsi 6:0:0:0: Direct-Access     Kingston DataTraveler 2.0 PMAP PQ: 0 ANSI: 0 CCS
[ 7446.708940] sd 6:0:0:0: Attached scsi generic sg2 type 0
[ 7448.482520] sd 6:0:0:0: [sdb] 2015232 512-byte logical blocks: (1.03 GB/984 MiB)

Notice the [sdb] on the last line I pasted. That means that this device can be found at /dev/sdb.

Check you devices by doing ls /dev/sdb* and you are likely to see something like:

$ ls /dev/sdb*
  /dev/sdb  /dev/sdb1

From there on you can go ahead with the exercise of mounting the partition sdb1to an empty directory. Skim through the start of man mount as a start.

Regarding disabling automount, take a look at: https://help.ubuntu.com/community/Mount/USB

  Configuring Automounting

  To enable or disable automount open a terminal and type dconf-editor
  followed by the [Enter] key.

  Browse to org.gnome.desktop.media-handling.

  The automount key controls whether to automatically mount media. If
  set to true, then Nautilus will automatically mount media such as
  user-visible hard disks and removable media on start-up and media
  insertion.

  There is another key org.gnome.desktop.media-handling.automount-open.
  This controls whether to automatically open a folder for automounted
  media.

  If set to true, then Nautilus will automatically open a folder when
  media is automounted. This only applies to media where no known
  x-content/* type was detected; for media where a known x-content type
  is detected, the user configurable action will be taken instead. This
  can be configured as shown below.


Pomsky is correct use shutter.

It has a screenshot tool, once you take your picture, it has a built in image editor, you can paint or whatever.  Shutter is the easiest tool you want.

Thanks to Organic Marble for commenting, pointing that shutter is now available according to this article

Another option, if you ever decide to switch to gimp, it has a built in screenshot tool

http://openoffice.blogs.com/openoffice/2010/01/taking-a-screen-shot-using-gimp.html

I'd use shutter anyway, simply because it's the best tool for screenshots on any OS. You can even upload the image directly to imgur or several other photo sharing sites from within shutter.

There's also Flameshot, here's an article about it on OMG Ubuntu. I didn't test it, but if OMG talks about it, it has to be good, and indeed from the looks of it on Github, it seems pretty good, maybe even better than shutter.

  The app lets take a screenshot of your whole screen or a specific
  section, annotate it, and then save it locally or upload to Imgur,
  with the URL automatically copied to your clipboard ready to paste
  elsewhere.

  A powerful open source screenshot and annotation tool for Linux,
  Flameshot has a varied set of markup tools available, including:

Freehand drawing
Lines
Arrows
Boxes
Circles
Highlighting
Blur

  You can customise the color, size and/or thickness of many of these
  image annotation tools.

  There are also on-screen buttons to:

Move screen selection
Undo
Copy to clipboard
Save file
Upload to Imgur

  Many of these options can be accessed by pressing keyboard shortcuts

I'm on ubuntu 16.04, unity, if you are too, follow this tutorial

https://mithun.co/software/install-flameshot-on-ubuntu-16-04/

That worked perfectly for me, just make sure to use sudo. The package included in Ubuntu 16.04 software center does not work, at least for me.


Some popular tools are missing in GIMP 2.10 in Ubuntu 20.04

Standard Heal Tool
It is certainly there in Gimp 2.10.22 (which I installed from ppa:ubuntuhandbook1/gimp), maybe it does not show up because the toolbars are grouped by default.
Go to Edit -> Preferences -> Interface -> Toolbox and uncheck Use tool groups.

Before and After

Note: The other answer is about Heal selection tool, which OP originally wanted to enable.


Your problem is that Ubuntu is using your speakers instead of your headphones. To fix this, follow these instructions:

Search for sound from your Dash
Open up the Sound Application, it is probably under your Settings
Choose the Output tab
Change your output to your headphones
Profit!


Why does Parallels 7 have such poor support for Ubuntu 12.04?

It all seems to be working with the latest version of Parallels 7 (August 3rd - ParallelsDesktop-7.0.15106.786747) that I just downloaded.  I'm guessing that it just took a few revisions for the Parallels developers to catch up with the changes to the new version of Ubuntu.


Quoting:

  After installing them, export both installation path, NDK version and API to use:

export ANDROIDSDK=/path/to/android-sdk
export ANDROIDNDK=/path/to/android-ndk
export ANDROIDNDKVER=rX
export ANDROIDAPI=X

# example
export ANDROIDSDK="/home/tito/code/android/android-sdk-linux_86"
export ANDROIDNDK="/home/tito/code/android/android-ndk-r7"
export ANDROIDNDKVER=r7
export ANDROIDAPI=14

  Also, you must configure you’re PATH to add the android binary:

export PATH=$ANDROIDNDK:$ANDROIDSDK/platform-tools:$ANDROIDSDK/tools:$PATH

Set all the necessary variables (add them to ~/.profile).


I installed Wine (a program that runs Windows programs on Linux) and used it to install C++, and the program works just fine now. You can see other forum posts on how to install Wine and its DLLs. It's actually quite easy.


I got this error trying to update to mono 6, I solved it by switching from keyserver.ubuntu.com to keys.gnupg.net


Trigger script execution on after apt-get upgrade for a certain package?

If this is an init script, you can usually make your tweaks in /etc/default/$PKG_NAME. Otherwise, you can use dpkg-divert to stop dpkg from touching the file.


As suggested by steeldriver I looked in /etc/environment and LD_LIBRARY_PATH was defined as

LD_LIBRARY_PATH="/usr/local/MATLAB/R2018a/runtime/glnxa64:/usr/local/MATLAB/R2018a/bin/glnxa64:/usr/local/MATLAB/R2018a/sys/os/glnxa64:/usr/local/MATLAB/R2018a/sys/opengl/lib/glnxa64"

I commented this line and ssh is working just fine. Matlab seems to run but I didn't looked in details if everything was working.

For those like me who didn't know what was LD_LIBRARY_PATH it's a colon-separated set of directories where libraries should be searched for first.


Is It safe to download programs by software center? and ubuntu software?

Ubuntu software (and the former software centre) generally uses apt for it packages and serve merely as a graphical interface for the same thing you can do with apt-get. Any package in the system can potentially have regressions (bugs that can cause issues) or security issues, though these are often fixed over time. It's for those two reasons why you recieve updates, and even more important why you should always run a supported version of Ubuntu and keep it up to date (if security and stability is of priority for you). Don't let this worry you though, this is the same with just about every OS out there and certainly isn't limited to Linux based OSes like Ubuntu.

In addition, sometimes when you're browsing the web you might be tempted to setup a PPA or to add a repository. Whenever you're adding repos that are not supported or maintained by Ubuntu you do run the risk of pulling down packages that aren't considered "safe", as the latest version of a particular package will always be pulled down from any repo unless otherwise pinned or the package is held. These packages could be unmaintained and have security vulnerabilities, or have regressions that could break the system.

Of course, if you're just using vanilla Ubuntu and not doing the above, then you'll be as safe as anybody else running Ubuntu, so have fun and feel free to use Ubuntu Software/Ubuntu Software Centre as often as you want.


How to layout the filesystem for a small SSD and a big HDD?

It's really up to you. You can do almost anything.

I have (to show off):

1x RAID0 PCI-E SSD (OCZ Revo 120gig) that runs at 540MB/s as the primary disk
4x 1.5TB disks in RAID5 as the "data" disk (called /media/ned)
2x 1.5TB disks in RAID1 (currently degraded - called /media/jeff)

Popular mounting convention would have me store the entire /home/ on ned... But this would slow down a lot of applications that use things in ~ to run (eg Firefox has a SQLite database that works best on  a fast disk).

Per that convention, I used to keep the entire /home/ on jeff. mdadm's RAID1 is considerably faster than its RAID5 but tons slower than my SSD. When half of jeff died, I decided I wanted more speed.

So now I just keep a directory on ned for things I really don't want on the SSD. This includes my ~/Music ~/Documents, etc. You can mount bind them in your fstab but I've just gone with SymLinks. Move the directory and run something like:

ln -s /media/ned/.fakehome/Music ~/Music

Rinse and repeat.

I my case, it's really a case of how much I can stand to lose if the worst happens. I have some security with RAID5 so anything not on it (especially the RAID0 SSD) is much more liable to die if a squirrel farts in its direction.

As you've only got a relatively tiny SSD and only one data disk, the metrics and causalities are slightly different. Each method is equally unsafe and you're limited by space. You might do best to mount all of home on the data disk and do the reverse of what I'm doing. Create a directory on the SSD for the things you want to be fast and SymLink them back out onto the data partition.

You can use fstab-mount commands but I just find SymLinks easier to maintain. I'm not sure what the performance overhead differences are like but I'm fairly sure I've asked somewhere.


Given a rEFInd installation on the OS X root partition, you should create the /EFI/refind/drivers_x64 or /EFI/refind/drivers directory and place your 64-bit drivers there. (Note that it's drivers_x64, not drivers_x86. I know that's confusing, but it's the naming convention for EFI -- ia32 for 32-bit x86 and x64 for 64-bit x86-64/AMD64.)


How to solve "Controller 'IDE Controller' does not support hotpluggin"?

Thank you~ @maythux 's answer is right.

I try to remove virtualbox-ose and install virtualbox on website( 2 files).

Then enable all the USB settings.

It works!

Thank you~


How to download ubuntu iso for dell laptop

You can find the latest dell image here.


You will need to do that in a live CD/USB(or other instance of linux if there is another one on the pc.)
Unmount the swap partition then and delete it. (I would also go into /etc/fstab and comment out the swap partition entry for now)
Then you can grow/resize your ubuntu(/dev/sda3) by 9 more gigs. The unallocated space needs to be adjacent(preferably to the right) to the partition you are resizing.
You can rebuild your swap partition in the 45G of unallocated space at the end... When you do this, you will need to correct the UUID in the swap entry in /etc/fstab... The new swap partition will have a new UUID. The UUID is displayed under "information" when you right click on the partition in gparted... or in a terminal use blkid. You should do this before you reboot.
(personally, I wouldn't waste so much space on swap... 1G is my limit for home computers...If I am using 1 gig of swap then my pc is most likely running like #%@^ and it will be rebooted at that point.... but I never get to even a quarter of that.... personal preference though)
.
.
.
If you want more than that (meaning that 45G of unused space).... you'd have to do the same thing but instead of growing the /home directly, you will be moving the space from the right to the left of /home... and then again like above, growing the "/" directory. This is where "risk" to your data starts to become a threat... Now you are moving partitions(/home) to the right... whenever that is the case, you need to weigh the risks/rewards.... I personally have never lost any data doing it, but I can see why it is said to be risky.


my screen resolution change will not save

I fixed it by going to Displays and set it there also.
thats it! :)


No Internet after reinstalling on Dell Mini 9

This problem may occur in wireless internet connection. First connect with wired Internet connection.

In terminal

sudo apt-get update
sudo apt-get upgrade

And then , you can try with wireless.

You also need to check

System>Administration>Hardware Drivers


Extract all files from a .tar.gz after wget and rename them

This should do the job:

$ tar -xzvf foo.tar && cd foo
$ for i in *; do echo $i |sed -re "s/[A-Za-z0-9]+(.*)/name\1/"; done

To do this in Python call:

new_str = re.sub('[A-Za-z]+(.*)', r'\name\1', old_str);

Here's another:

$ for i in *; do echo name.${i#*.}; done


There are some design packages available in the Ubuntu Software center, and a Google search will provide reviews of their capabilities.  Solidworks itself does not support Linux.  Unigraphics does have a Linux port, although I do not know the cost of this program.

For operation of the Windows based programs, using a virtual machine to emulate Windows does work - I run Solidworks in a Windows XP based in VMWare, and have been quite happy with the performance that I obtain.


Upgrading the mainline 3.9 kernel appears to solve it.

See here for installation direction.


Is grep 2.25 the most recent version available for ubuntu 16.04?

You can visit packages.ubuntu.com and determine version numbers (2.25 on xenial, 3.1 on bionic).

You can always install 18.04 LTS on VM and test grep here.

Also you can compare man 1 grep-pages on xenial and on bionic to determine the differences.


When both wired and wireless network connections are active, which one is used?

The wired network is preferred.

https://help.ubuntu.com/community/NetworkManager0.7


Rather than finding the root cause of this probably-bug, try the PDF-workaround.

Print to a file (PDF) first, then print this PDF from your favourite PDF viewer.


You have to create a Live USB Boot Drive with persistence enabled.
See here


Eye strain after using Ubuntu for some time

One possible cause could be incorrect refresh rate and (or) resolution. This was a generic issue in the time of CRT monitors being, but we could experience similar issues also with the modern monitors. So, find the the monitor's specification and check what are the native values of the refresh rate and the resolution. Or find these values in Windows [1].  Then use xrandr to check the current values (the line marked with asterisk *) and compare them with the default ones.

Unfortunately xrandr has really limited functionalities [2] [3] within Ubuntu 17.10 under Wayland [4]. But it will provide enough information.

If this is the problem the next question should be - how do I change these values within the certain Ubuntu version?

If it is 17.10 on Wayland, you may try to find the native values under the menu Displays, as it is shown on the image from the @pomsky's answer. If they don't exist, you could try to follow this answer, where @Panther describes how to generate and enable custom resolution under Wayland.

Another possible way to solve this problem is to run Ubuntu on Xorg, where xrandr will be more useful. Then you could try to use some solution as these suggested here.


Check /lost+found in case there was a disk problem and a lot of junk ended up being detected as separate files, possibly wrongly.

Check iostat to see if some application is still producing files like crazy.

find / -xdev -type d -size +100k will tell you if there's a directory that uses more than 100kB of disk space. That would be a directory that contains a lot of files, or contained a lot of files in the past. You may want to adjust the size figure.

I don't think there's a combination of options to GNU du to make it count 1 per directory entry. You can do this by producing the list of files with find and doing a little bit of counting in awk. Here is a du for inodes. Minimally tested, doesn't try to cope with file names containing newlines.

#!/bin/sh
find "$@" -xdev -depth | awk '{
    depth = $0; gsub(/[^\/]/, "", depth); depth = length(depth);
    if (depth < previous_depth) {
       # A non-empty directory: its predecessor was one of its files
       total[depth] += total[previous_depth];
       print total[previous_depth] + 1, $0;
       total[previous_depth] = 0;
    }
    ++total[depth];
    previous_depth = depth;
}
END { print total[0], "total"; }'

Usage: du-inodes /. Prints a list of non-empty directories with the total count of entries in them and their subdirectories recursively. Redirect the output to a file and review it at your leisure. sort -k1nr <root.du-inodes | head will tell you the biggest offenders.


Ubuntu shows only console login after I start my computer

I think the server version was installed on your box. You should install desktop environment by running one of these commands in terminal:

sudo apt-get install ubuntu-desktop #GNOME
sudo apt-get install kubuntu-desktop #KDE
sudo apt-get install xubuntu-desktop #xfce


After apt upgrade - getting “(initramfs) unable to find a medium containing a live file system” on custom Live USB

This sounds like the casper-rw persistence file has been filled and has no more space left.

It is generally recommended not to do an update on a persistent usb drive as this quickly fills the casper-rw file which is limited to 4GB in size.

It is not possible to easily do an upgrade to a Persistent or Live drive as the kernel is part of a read only squashFS file.

To confirm if this is the problem try temporarily renaming the casper-rw file and rebooting.

You can also mount and access the casper-rw file thus:

mkdir /tmp/casper
sudo mount -o loop /path/to/casper-rw /tmp/casper

If you are using a casper-rw persistent partition, it can be accessed from a second Live USB or Live DVD.

Automatic updates should be turned off with persistent drives.

Edit:
If the drive was made using mkusb there is probably a NTFS partition named usbdata.

If this partition gets fragmented, as NTFS partitions sometimes do, you can get the same error message. Try backing up and reformatting this partition.

There is a chance that this partition can be defragged in Windows 10. I prefer not to mess with multi partition flash drives in Windows.

Fragmenting can be a sign that the drive was unplugged while being written to, don't do that.


How do I add the SVN add-on Subclipse to Eclipse?

Got it worked out. Very simple solution. Just added

-Djava.library.path=/usr/lib/jni

after -vmargs in eclipse.ini file and restarted the IDE.

This solution won't work if you did a manual installation of eclipse, for example if you wanted to use a newer version than the one on the software centre


Can receive email, can send email to local domain, can't send email to other mailservers

I figured out the problem, it was related to /etc/postfix/mysql*.cf files, which I entered a wrong password in one of them.
Now everything works fine!


What's the relation between different Touch install instructions for the Nexus 7?

The Nexus7 Project and the Ubuntu Touch Project is different. The former link directs you to the installation of Ubuntu Desktop in Nexus 7 while the latter directs you to install the touch-friendly Ubuntu Touch project on Galaxy Nexus, Nexus 4, Nexus 7 and Nexus 10.


Switching between graphics driver in combined dual boot/Virtualbox setup

I have managed to succeed in my efforts to get this undoubtedly exotic setup to work as I want it too.

After a reinstall of Ubuntu, the problems with installed guest additions for the natively booted system disappeared.

The only remaining problem was being unable to login into the virtual machine desktop with fglrx drivers installed. Although the kernel modules always adopted correctly to the corresponding environment (vbox modules only running inside the virtual machine and fglrx module only running when booted natively) there seemed to be something still preventing the start of the desktop environment inside the virtual machine.

This turned out to be the AMD libglx libraries, which were still in use for the virtual machine.

Fortunately, the fglrx driver software provides an easy switch command from amd to intel, so all that needed to be done was executing

sudo /usr/lib/fglrx/switchlibglx intel

and restart lightdm.

To have this executed automatically during boot, I created a file named "checkvga.conf" in /etc/init/ reading

# Checks if VGA belongs to virtual machine

description      "Checks if VGA belongs to virtual machine"

start on starting lightdm

script
    if test -f /proc/modules &&  grep -q vboxguest /proc/modules 2>/dev/null; then
    /usr/lib/fglrx/switchlibglx intel
    restart lightdm
    fi
end script

I had to put in the "restart lightdm" command to get it to work reliable, although I originally had assumed that "start on starting lightdm" would have been enough to have this command executed before lightdm was launched the first time. The reason might be that actually, X is required to be restarted, since there might have already been an instance of it to display the splash screen during boot. If someone knows, please enlighten me.


Installing Disastry's PGP 2.6.3ia multi06 on 12.04 LTS

You will have to put it somewhere in your $PATH. A common place would be /usr/local/bin, which is for software installed on your own (but make sure the folder actually is in your $PATH variable, or add it).

If you just want to see if the very outdated binary is still able to run in your system, execute it by typing the path to it (or running ./pgp if it is in your working directory).

Pretty much the same applies if you compiled it on your own, but expect serious dependency problems with software created for 11+ years old environments.

Anyway: Are you sure you want to use security-critical software that wasn't updated for 11 years from some more or less random site on the internet? Furthermore, it inclines severe compatibility issues, and never heard of RFC4880 in use today, and the next update is already in queue... You even cannot read pretty much all recent OpenPGP (v4) keys.


Your system is having a problem with the IPv6 settings.  You can disable it with:

$ sudo nano /etc/sysctl.conf

Append this:

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

Run this command:

$ sudo sysctl -p

Details at: https://help.ubuntu.com/community/WebBrowsingSlowIPv6IPv4

In the future if you wish to reenable IPv6 just remove the appended lines from your /etc/syst.conf file.


Can we move mouse cursor by keyboard command in Ubuntu?

If you indeed want do that from the command line, then you can install xdotool (it is packaged in Ubuntu 16.04 at least) and issue commands like this:

xdotool mousemove 10 500 && xdotool click 1


dd will partition the disk for you according to http://www.linuxquestions.org/questions/linux-newbie-8/learn-the-dd-command-362506/.


I am stuck on this part of configuring the virtualbox-ext-pack ubuntu-vm. How do i continue to the next step

You have to move focus to the terminal window and then hit Tab to move cursor to the <Ok> interface item and then hit Enter to proceed.


Best way to record VNC session (VLC screencast)?

You can record a vnc session without even opening a VNC client using vnc2flv: http://www.unixuser.org/~euske/python/vnc2flv/
It does record in flv but there should not be a problem to convert the output to anything else you need.


The easiest way is to use the entire Ondřej Surý PHP5 PPA by adding it as a repository source on your server. Instructions (and the packages it's going to upgrade — note that this will include PHP) are right there on the page but using it is simple enough:

sudo add-apt-repository ppa:ondrej/php5
sudo apt-get update
sudo apt-get dist-upgrade

If you have production sites, you should first test them with the stack being offered in this PPA (newer apache 2.4, php, libmemcached, etc). I've given you just enough information to be completely deadly.

If you don't backup or test beforehand, you're not doing it right.

Or you can try just downloading the XCache package from the PPA (click the architecture you need) and dpkg -i <filename>... But be aware that that version of XCache may well be incompatible with ancient versions of PHP. You might need the full PHP stack offered here.


Kubuntu 13.10 no sound, missing shutdown button, network disconnected

I think I had the same thing happen to me.  I didn't know it but my upgrade to Kubuntu 13.10 got interrupted.  When I ran the apt-get command, it told me it was interrupted and the command to run.  Try this command first:

sudo dpkg --configure -a

It seemed to work for me, my network icon had a red x, my shutdown and restart buttons were gone, and my sound wouldn't work.  After I ran the command, it all came back after I re-booted.


How do I stop apt-get operations listing large amounts of Marking: and Following dep: entries

It appears to be the Debug::pkgAutoRemove option. From man apt.conf:

Debug::pkgAutoRemove
    Log events related to the automatically-installed status of
    packages and to the removal of unused packages.

Although the above description is not entirely helpful, you can confirm by looking at the apt source - specifically, apt-1.3.5/apt-pkg/depcache.cc:

   bool const debug_autoremove = _config->FindB("Debug::pkgAutoRemove", false);
   if(debug_autoremove)
      std::clog << "Marking: " << Pkg.FullName() << " " << Ver.VerStr() << std::endl;

You should be able to turn it off by finding and modifying the setting in your /etc/apt.conf or /etc/apt.conf.d/xxx files, or on the command line using the -o option e.g.

sudo apt-get -oDebug::pkgAutoRemove=false install foo


Unable to create a file in a certain location on Ubuntu

MySQL is run fom the mysql user. If you want a MySQL script to write into user user's home you need to provide the right permissions to mysql. For instance, you can pass the ownership of the feeds folder to mysql:

chown mysql:mysql /home/user/feeds

Or to pass ownership of the text file:

touch /home/user/feeds/file.txt

chown mysql:mysql /home/user/feeds/file.txt


How to create DOS Boot USB flash drive with (X)Ubuntu

Install UNetbootin in the Live CD and select FreeDOS as the distribution, which will download a 1.44 MB boot image and create a DOS boot disk for you. UNetbootin is also available for Windows

If you're curious the image is named ubninit and can be mounted in linux:

livewire@ZS00:/media/VOYAGER$ mkdir test
livewire@ZS00:/media/VOYAGER$ sudo mount -o loop ubninit test
[sudo] password for livewire:
livewire@ZS00:/media/VOYAGER$ ll test/
insgesamt 125
drwxr-xr-x  4 root     root      7168 Jan  1  1970 ./
drwx------ 17 livewire livewire  4096 Aug 26 15:19 ../
-rwxr-xr-x  1 root     root     66945 Sep  3  2006 command.com*
drwxr-xr-x  2 root     root      1024 Sep  3  2006 driver/
-rwxr-xr-x  1 root     root      1768 Sep  3  2006 fdconfig.sys*
drwxr-xr-x  2 root     root      1024 Sep  3  2006 freedos/
-rwxr-xr-x  1 root     root     45341 Sep  3  2006 kernel.sys*
livewire@ZS00:/media/VOYAGER$ file ubninit
ubninit: DOS floppy 1440k, x86 hard disk boot sector


I suppose that you did have a look at this manual section and that it was not clear enough ?
http://www.lesbonscomptes.com/recoll/usermanual/usermanual.html#RCL.SEARCH.LANG.MODIFIERS

Stemming is the operation which turns a derived term like "floors", "flooring" into a base one (the stem): floor. This means that searching for "floors" will also find texts which only contain "floor". Sometimes, this is undesirable, so Recoll lets you turn it off either by capitalizing the term ("Floors"), or by using the 'l' modifier.

Normally, a double quoted input to Recoll tells it to look for the input terms in the order given, without any intermediate terms. Searching for "first second" (actually double quoted in the entry) will not find texts only containing [second first] or [first a second]

A double-quoted entry can be turned into a "proximity search" by adding a 'p' modifier. "first second"p will find texts containing [first second] but also ones containing [second first], but not any only containing [first a second] or [second a first].

The o modifier lets you specify that some intervening terms may appear. For example "first second"o1 will match both [first second] and [first a second]

For most queries, you don't need this stuff at all, but sometimes, they can make the difference between finding hundred of uninteresting results and finding just the one you want.


Trying to access debian/scripts and debian/rules

If you cloned sources from Ubuntu git or using a deb source package, then debian directory is at the second level. Like that

git clone git://kernel.ubuntu.com/ubuntu/ubuntu-precise.git
cd ubuntu-precise

And you will see "debian" in ls.
But actually you do not need to set +x. It must be already there.
Just do

fakeroot debian/rules clean
fakeroot debian/rules binary-headers binary-generic

and it will build.


Why the "Filesystem root" has only XXX disk space remaining?

The space that is showing as "unused" is not necessarily available to the user.

Specifically, filesystems from the ext family reserve a number of disk blocks for system tasks as described here:

ext2/3/4 reserved blocks percentage purpose
Reserved space for
root on a filesystem - why?

The default amount of reserved space for these filesystems is 5%.

From your screenshots we can see that your root filesystem is located on a partition of size 48.83GiB, so we would expect 48.83 x .05 = 2.44GiB reserved. The unused space is shown as 3.13GiB so that the available space should then be 3.13 - 2.44 = 0.69GiB - close to the 722.6MB shown by the warning message. (There will be rounding errors since the usage is only given to 2 decimals; also one is GiB and one is MB).

You can confirm the reserved block fraction using the dumpe2fs utility. For example, using my own boot partition:

sudo dumpe2fs /dev/sda1 | less

I can see that

Block count:              248832
Reserved block count:     12441

from which the reserved percentage is 12441/248832 x 100 = 5.00% as expected.

The reserved block fraction can be modified using the tune2fs utility, however I would not recommend doing that in this case - it's more appropriate for large (>TB) and/or non-system disks.


In Ubuntu 14.04 open the terminal and type:

sudo add-apt-repository 'deb http://deb.versatica.com trusty main'
wget -O - http://deb.versatica.com/deb.versatica.com.key | sudo apt-key add -
sudo apt-get update
sudo apt-get install oversip

In Ubuntu 12.04 open the terminal and type:

sudo add-apt-repository 'deb http://deb.versatica.com precise main'
wget -O - http://deb.versatica.com/deb.versatica.com.key | sudo apt-key add -
sudo apt-get update
sudo apt-get install oversip