For Yelp to find your application's help pages, they should be installed under:

/usr/share/gnome/help/$app_name/$locale/

As for where to find this information... Well, you're right. I don't see this clearly documented anywhere. GNOME Handbook of Writing Software Documentation does include a section that includes information on how to incorporate it into the build system, but it assumes that you are using autotools.

I usually just look at examples that I have installed on my system. For instance, I can see that Totem shows up in Yelp -> Go -> All Documents. So let's see where it installs its documentation:

$ dpkg -L totem-common | grep "help"
/usr/share/gnome/help
/usr/share/gnome/help/totem
/usr/share/gnome/help/totem/cs
/usr/share/gnome/help/totem/cs/figures
/usr/share/gnome/help/totem/gl
/usr/share/gnome/help/totem/gl/figures
/usr/share/gnome/help/totem/pa
/usr/share/gnome/help/totem/pa/figures
/usr/share/gnome/help/totem/fi
/usr/share/gnome/help/totem/fi/figures
/usr/share/gnome/help/totem/pl
/usr/share/gnome/help/totem/pl/figures
/usr/share/gnome/help/totem/zh_CN
/usr/share/gnome/help/totem/zh_CN/figures
/usr/share/gnome/help/totem/uk
/usr/share/gnome/help/totem/uk/figures
/usr/share/gnome/help/totem/pt_BR
/usr/share/gnome/help/totem/pt_BR/figures
/usr/share/gnome/help/totem/zh_HK
/usr/share/gnome/help/totem/zh_HK/figures
/usr/share/gnome/help/totem/eu
/usr/share/gnome/help/totem/eu/figures
/usr/share/gnome/help/totem/C
/usr/share/gnome/help/totem/C/totem.xml
/usr/share/gnome/help/totem/C/figures
/usr/share/gnome/help/totem/C/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/C/figures/totem_next_button.png
/usr/share/gnome/help/totem/C/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/C/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/C/figures/totem_previous_button.png
/usr/share/gnome/help/totem/C/figures/totem_start_window.png
/usr/share/gnome/help/totem/C/figures/totem_play_button.png
/usr/share/gnome/help/totem/C/figures/totem_pause_button.png
/usr/share/gnome/help/totem/C/legal.xml
/usr/share/gnome/help/totem/ca
/usr/share/gnome/help/totem/ca/figures
/usr/share/gnome/help/totem/sl
/usr/share/gnome/help/totem/sl/figures
/usr/share/gnome/help/totem/it
/usr/share/gnome/help/totem/it/figures
/usr/share/gnome/help/totem/zh_TW
/usr/share/gnome/help/totem/zh_TW/figures
/usr/share/gnome/help/totem/te
/usr/share/gnome/help/totem/te/figures
/usr/share/gnome/help/totem/ja
/usr/share/gnome/help/totem/ja/figures
/usr/share/gnome/help/totem/de
/usr/share/gnome/help/totem/de/figures
/usr/share/gnome/help/totem/bg
/usr/share/gnome/help/totem/bg/figures
/usr/share/gnome/help/totem/el
/usr/share/gnome/help/totem/el/figures
/usr/share/gnome/help/totem/ru
/usr/share/gnome/help/totem/ru/figures
/usr/share/gnome/help/totem/oc
/usr/share/gnome/help/totem/oc/figures
/usr/share/gnome/help/totem/fr
/usr/share/gnome/help/totem/fr/figures
/usr/share/gnome/help/totem/en_GB
/usr/share/gnome/help/totem/en_GB/figures
/usr/share/gnome/help/totem/es
/usr/share/gnome/help/totem/es/figures
/usr/share/gnome/help/totem/sv
/usr/share/gnome/help/totem/sv/figures
/usr/share/gnome/help/totem/ro
/usr/share/gnome/help/totem/ro/figures
/usr/share/gnome/help/totem/da
/usr/share/gnome/help/totem/da/figures
/usr/share/gtk-doc/html/totem/totem.devhelp2
/usr/share/gnome/help/totem/cs/totem.xml
/usr/share/gnome/help/totem/cs/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/cs/figures/totem_next_button.png
/usr/share/gnome/help/totem/cs/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/cs/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/cs/figures/totem_previous_button.png
/usr/share/gnome/help/totem/cs/figures/totem_start_window.png
/usr/share/gnome/help/totem/cs/figures/totem_play_button.png
/usr/share/gnome/help/totem/cs/figures/totem_pause_button.png
/usr/share/gnome/help/totem/gl/totem.xml
/usr/share/gnome/help/totem/gl/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/gl/figures/totem_next_button.png
/usr/share/gnome/help/totem/gl/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/gl/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/gl/figures/totem_previous_button.png
/usr/share/gnome/help/totem/gl/figures/totem_start_window.png
/usr/share/gnome/help/totem/gl/figures/totem_play_button.png
/usr/share/gnome/help/totem/gl/figures/totem_pause_button.png
/usr/share/gnome/help/totem/pa/totem.xml
/usr/share/gnome/help/totem/pa/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/pa/figures/totem_next_button.png
/usr/share/gnome/help/totem/pa/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/pa/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/pa/figures/totem_previous_button.png
/usr/share/gnome/help/totem/pa/figures/totem_start_window.png
/usr/share/gnome/help/totem/pa/figures/totem_play_button.png
/usr/share/gnome/help/totem/pa/figures/totem_pause_button.png
/usr/share/gnome/help/totem/fi/totem.xml
/usr/share/gnome/help/totem/fi/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/fi/figures/totem_next_button.png
/usr/share/gnome/help/totem/fi/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/fi/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/fi/figures/totem_previous_button.png
/usr/share/gnome/help/totem/fi/figures/totem_start_window.png
/usr/share/gnome/help/totem/fi/figures/totem_play_button.png
/usr/share/gnome/help/totem/fi/figures/totem_pause_button.png
/usr/share/gnome/help/totem/pl/totem.xml
/usr/share/gnome/help/totem/pl/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/pl/figures/totem_next_button.png
/usr/share/gnome/help/totem/pl/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/pl/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/pl/figures/totem_previous_button.png
/usr/share/gnome/help/totem/pl/figures/totem_start_window.png
/usr/share/gnome/help/totem/pl/figures/totem_play_button.png
/usr/share/gnome/help/totem/pl/figures/totem_pause_button.png
/usr/share/gnome/help/totem/zh_CN/totem.xml
/usr/share/gnome/help/totem/zh_CN/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/zh_CN/figures/totem_next_button.png
/usr/share/gnome/help/totem/zh_CN/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/zh_CN/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/zh_CN/figures/totem_previous_button.png
/usr/share/gnome/help/totem/zh_CN/figures/totem_start_window.png
/usr/share/gnome/help/totem/zh_CN/figures/totem_play_button.png
/usr/share/gnome/help/totem/zh_CN/figures/totem_pause_button.png
/usr/share/gnome/help/totem/uk/totem.xml
/usr/share/gnome/help/totem/uk/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/uk/figures/totem_next_button.png
/usr/share/gnome/help/totem/uk/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/uk/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/uk/figures/totem_previous_button.png
/usr/share/gnome/help/totem/uk/figures/totem_start_window.png
/usr/share/gnome/help/totem/uk/figures/totem_play_button.png
/usr/share/gnome/help/totem/uk/figures/totem_pause_button.png
/usr/share/gnome/help/totem/pt_BR/totem.xml
/usr/share/gnome/help/totem/pt_BR/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/pt_BR/figures/totem_next_button.png
/usr/share/gnome/help/totem/pt_BR/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/pt_BR/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/pt_BR/figures/totem_previous_button.png
/usr/share/gnome/help/totem/pt_BR/figures/totem_start_window.png
/usr/share/gnome/help/totem/pt_BR/figures/totem_play_button.png
/usr/share/gnome/help/totem/pt_BR/figures/totem_pause_button.png
/usr/share/gnome/help/totem/zh_HK/totem.xml
/usr/share/gnome/help/totem/zh_HK/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/zh_HK/figures/totem_next_button.png
/usr/share/gnome/help/totem/zh_HK/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/zh_HK/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/zh_HK/figures/totem_previous_button.png
/usr/share/gnome/help/totem/zh_HK/figures/totem_start_window.png
/usr/share/gnome/help/totem/zh_HK/figures/totem_play_button.png
/usr/share/gnome/help/totem/zh_HK/figures/totem_pause_button.png
/usr/share/gnome/help/totem/eu/totem.xml
/usr/share/gnome/help/totem/eu/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/eu/figures/totem_next_button.png
/usr/share/gnome/help/totem/eu/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/eu/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/eu/figures/totem_previous_button.png
/usr/share/gnome/help/totem/eu/figures/totem_start_window.png
/usr/share/gnome/help/totem/eu/figures/totem_play_button.png
/usr/share/gnome/help/totem/eu/figures/totem_pause_button.png
/usr/share/gnome/help/totem/ca/totem.xml
/usr/share/gnome/help/totem/ca/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/ca/figures/totem_next_button.png
/usr/share/gnome/help/totem/ca/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/ca/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/ca/figures/totem_previous_button.png
/usr/share/gnome/help/totem/ca/figures/totem_start_window.png
/usr/share/gnome/help/totem/ca/figures/totem_play_button.png
/usr/share/gnome/help/totem/ca/figures/totem_pause_button.png
/usr/share/gnome/help/totem/sl/totem.xml
/usr/share/gnome/help/totem/sl/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/sl/figures/totem_next_button.png
/usr/share/gnome/help/totem/sl/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/sl/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/sl/figures/totem_previous_button.png
/usr/share/gnome/help/totem/sl/figures/totem_start_window.png
/usr/share/gnome/help/totem/sl/figures/totem_play_button.png
/usr/share/gnome/help/totem/sl/figures/totem_pause_button.png
/usr/share/gnome/help/totem/it/totem.xml
/usr/share/gnome/help/totem/it/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/it/figures/totem_next_button.png
/usr/share/gnome/help/totem/it/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/it/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/it/figures/totem_previous_button.png
/usr/share/gnome/help/totem/it/figures/totem_start_window.png
/usr/share/gnome/help/totem/it/figures/totem_play_button.png
/usr/share/gnome/help/totem/it/figures/totem_pause_button.png
/usr/share/gnome/help/totem/zh_TW/totem.xml
/usr/share/gnome/help/totem/zh_TW/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/zh_TW/figures/totem_next_button.png
/usr/share/gnome/help/totem/zh_TW/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/zh_TW/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/zh_TW/figures/totem_previous_button.png
/usr/share/gnome/help/totem/zh_TW/figures/totem_start_window.png
/usr/share/gnome/help/totem/zh_TW/figures/totem_play_button.png
/usr/share/gnome/help/totem/zh_TW/figures/totem_pause_button.png
/usr/share/gnome/help/totem/te/totem.xml
/usr/share/gnome/help/totem/te/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/te/figures/totem_next_button.png
/usr/share/gnome/help/totem/te/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/te/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/te/figures/totem_previous_button.png
/usr/share/gnome/help/totem/te/figures/totem_start_window.png
/usr/share/gnome/help/totem/te/figures/totem_play_button.png
/usr/share/gnome/help/totem/te/figures/totem_pause_button.png
/usr/share/gnome/help/totem/ja/totem.xml
/usr/share/gnome/help/totem/ja/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/ja/figures/totem_next_button.png
/usr/share/gnome/help/totem/ja/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/ja/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/ja/figures/totem_previous_button.png
/usr/share/gnome/help/totem/ja/figures/totem_start_window.png
/usr/share/gnome/help/totem/ja/figures/totem_play_button.png
/usr/share/gnome/help/totem/ja/figures/totem_pause_button.png
/usr/share/gnome/help/totem/de/totem.xml
/usr/share/gnome/help/totem/de/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/de/figures/totem_next_button.png
/usr/share/gnome/help/totem/de/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/de/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/de/figures/totem_previous_button.png
/usr/share/gnome/help/totem/de/figures/totem_start_window.png
/usr/share/gnome/help/totem/de/figures/totem_play_button.png
/usr/share/gnome/help/totem/de/figures/totem_pause_button.png
/usr/share/gnome/help/totem/bg/totem.xml
/usr/share/gnome/help/totem/bg/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/bg/figures/totem_next_button.png
/usr/share/gnome/help/totem/bg/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/bg/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/bg/figures/totem_previous_button.png
/usr/share/gnome/help/totem/bg/figures/totem_start_window.png
/usr/share/gnome/help/totem/bg/figures/totem_play_button.png
/usr/share/gnome/help/totem/bg/figures/totem_pause_button.png
/usr/share/gnome/help/totem/el/totem.xml
/usr/share/gnome/help/totem/el/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/el/figures/totem_next_button.png
/usr/share/gnome/help/totem/el/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/el/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/el/figures/totem_previous_button.png
/usr/share/gnome/help/totem/el/figures/totem_start_window.png
/usr/share/gnome/help/totem/el/figures/totem_play_button.png
/usr/share/gnome/help/totem/el/figures/totem_pause_button.png
/usr/share/gnome/help/totem/ru/totem.xml
/usr/share/gnome/help/totem/ru/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/ru/figures/totem_next_button.png
/usr/share/gnome/help/totem/ru/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/ru/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/ru/figures/totem_previous_button.png
/usr/share/gnome/help/totem/ru/figures/totem_start_window.png
/usr/share/gnome/help/totem/ru/figures/totem_play_button.png
/usr/share/gnome/help/totem/ru/figures/totem_pause_button.png
/usr/share/gnome/help/totem/oc/totem.xml
/usr/share/gnome/help/totem/oc/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/oc/figures/totem_next_button.png
/usr/share/gnome/help/totem/oc/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/oc/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/oc/figures/totem_previous_button.png
/usr/share/gnome/help/totem/oc/figures/totem_start_window.png
/usr/share/gnome/help/totem/oc/figures/totem_play_button.png
/usr/share/gnome/help/totem/oc/figures/totem_pause_button.png
/usr/share/gnome/help/totem/fr/totem.xml
/usr/share/gnome/help/totem/fr/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/fr/figures/totem_next_button.png
/usr/share/gnome/help/totem/fr/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/fr/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/fr/figures/totem_previous_button.png
/usr/share/gnome/help/totem/fr/figures/totem_start_window.png
/usr/share/gnome/help/totem/fr/figures/totem_play_button.png
/usr/share/gnome/help/totem/fr/figures/totem_pause_button.png
/usr/share/gnome/help/totem/en_GB/totem.xml
/usr/share/gnome/help/totem/en_GB/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/en_GB/figures/totem_next_button.png
/usr/share/gnome/help/totem/en_GB/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/en_GB/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/en_GB/figures/totem_previous_button.png
/usr/share/gnome/help/totem/en_GB/figures/totem_start_window.png
/usr/share/gnome/help/totem/en_GB/figures/totem_play_button.png
/usr/share/gnome/help/totem/en_GB/figures/totem_pause_button.png
/usr/share/gnome/help/totem/es/totem.xml
/usr/share/gnome/help/totem/es/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/es/figures/totem_next_button.png
/usr/share/gnome/help/totem/es/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/es/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/es/figures/totem_previous_button.png
/usr/share/gnome/help/totem/es/figures/totem_start_window.png
/usr/share/gnome/help/totem/es/figures/totem_play_button.png
/usr/share/gnome/help/totem/es/figures/totem_pause_button.png
/usr/share/gnome/help/totem/sv/totem.xml
/usr/share/gnome/help/totem/sv/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/sv/figures/totem_next_button.png
/usr/share/gnome/help/totem/sv/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/sv/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/sv/figures/totem_previous_button.png
/usr/share/gnome/help/totem/sv/figures/totem_start_window.png
/usr/share/gnome/help/totem/sv/figures/totem_play_button.png
/usr/share/gnome/help/totem/sv/figures/totem_pause_button.png
/usr/share/gnome/help/totem/ro/totem.xml
/usr/share/gnome/help/totem/ro/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/ro/figures/totem_next_button.png
/usr/share/gnome/help/totem/ro/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/ro/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/ro/figures/totem_previous_button.png
/usr/share/gnome/help/totem/ro/figures/totem_start_window.png
/usr/share/gnome/help/totem/ro/figures/totem_play_button.png
/usr/share/gnome/help/totem/ro/figures/totem_pause_button.png
/usr/share/gnome/help/totem/da/totem.xml
/usr/share/gnome/help/totem/da/figures/totem_show_playlist_button.png
/usr/share/gnome/help/totem/da/figures/totem_next_button.png
/usr/share/gnome/help/totem/da/figures/totem_volume_mute_button.png
/usr/share/gnome/help/totem/da/figures/totem_volume_maximum_button.png
/usr/share/gnome/help/totem/da/figures/totem_previous_button.png
/usr/share/gnome/help/totem/da/figures/totem_start_window.png
/usr/share/gnome/help/totem/da/figures/totem_play_button.png
/usr/share/gnome/help/totem/da/figures/totem_pause_button.png


Xenial Failed to fetch...404 on any package install

The Ubuntu ports repository does not include any x86 packages, which is why you see these errors:

E: Failed to fetch http://ports.ubuntu.com/ubuntu ports/dists/xenial/main/binary-i386/Packages  404  Not Found [IP: 91.189.88.150 80]
E: Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/xenial-updates/main/binary-i386/Packages  404  Not Found [IP: 91.189.88.150 80]
E: Failed to fetch http://ports.ubuntu.com/ubuntu-ports/dists/xenial-security/main/binary-i386/Packages  404  Not Found [IP: 91.189.88.150 80]

Because of these errors, no package list from this repository was loaded. So the armhf packages that would have been otherwise available aren't.

Since you don't seem to be using i386 repos, just remove that, and run apt-get update again:

sudo dpkg --remove-architecture i386
sudo apt update

The ports.ubuntu.com package lists should now be downloaded in /var/lib/apt/lists/, and packages should be available.


Using KDE - Application Menus Missing in Qt Apps

This sounds like https://bugs.launchpad.net/ubuntu/+source/appmenu-qt5/+bug/1307619. Another work-around is to unset QT_QPA_PLATFORMTHEME in your environment.


Difference between executable directory vs executable files

No, the executable permission for directories means that you can enter the directory, making it your present working directory using cd, and see which files it contains.

It's useful to think of a directory just as a file which is a list of file names.

Read bit - If set, you can read this list. If you have a directory named books:

You can ls books and you'll get a list of the files it contains (-l won't work however).
You can use command-line completion i.e. touch books/bo+Tab to get
books/bookfile.
You cannot make books your working directory, cd won't work.

Write bit - You can modify this list names on it. You can only do this if the execute bit is also set.

Execute bit - You need this permission if you want to:

Have any access to files within the directory.
Modify details of the list itself. You can add, rename or delete names on the list, but this also requires write permission on the directory.

Setting the execute bit on a directory does not in any way affect the files themselves, but it does affect your access to them. For instance if you have write and execute access for a directory, you can move, rename and delete files, even if you can't write into the files themselves.


NOTE: *JDK * is required for installing and running the Java SE, Java EE and All NetBeans Bundles.

How do I install Java?

How do I install Oracle JDK 6?

How do I install Oracle Java JDK 7?

How can I install Sun/Oracle's proprietary Java JDK 6/7/8 or JRE?

Install Netbeans

Go to Netbeans download page and download the netbeans Linux (x86/x64) .sh installer file (like netbeans-7.0.1-ml-linux.sh).
Copy your Netbeans installer file to your Desktop.
Open Terminal.To open terminal click the Dash home from unity launcher.And type terminal in the search field.And click Terminal.
Type the below code in terminal and hit enter. cd Desktop
Then type below code in terminal and hit enter sudo chmod +x netbeans-* Type your ubuntu password if needed and press enter.
Then type below code and press enter sudo ./netbeans-*
And then install Netbeans from GUI installer window. After the successful installation,click the Dash home from unity launcher.And type netbeans in the search field.And click Netbeans IDE 7.0.1 to open.

Related question :

How to uninstall NetBeans?


Possible to run cron in foreground?

command=service cron start

Should be instead:

command=cron -f


Delete multiple columns using awk or sed

If the column delimiter in your file is a single character, e.g. a space, cut can do that easily:

cut -d' ' -f-676 <in >out

This prints only the space-separated columns from the first to the 676th.

If you need e.g. every whitespace character to count as a delimiter, a sed solution is:

sed -r 's/\s+\S+//677g' <in >out

This replaces every column (= at least one whitespace character followed by at least one non-whitespace character) beginning with the 677th with nothing. Using character groups you can specify any set of delimiters you need, e.g. for “4”, “#” and “K”:

sed -r 's/[4#K]+[^4#K]+//677g' <in >out

For a reasonable awk approach kindly refer to steeldriver’s answer, but here is another one looping over the columns and only printing them (separated by FS) if their number is <= 676:

awk '{for (i=1;i<=676;i++) {printf (i==1?"":FS)$i}; print ""}' <in >out

For a character group you have to specify the output field separator for the output, e.g. for [4#K] and "sep":

awk -F'[4#K]' '{for (i=1;i<=676;i++) {printf (i==1?"":"sep")$i}; print ""}' <in >out


unable to install bootloader, grub dev/sda

The error messages seem to indicate a failing disk drive specifically issues accessing sector 63 which will be inside the MBR unfortunately that rules out workarounds like badblocks should that be the case.

I'd recommend that you use smart to test the drive, to do so boot the machine using the live CD then type this command to install the smart tools into the live CD environment:

sudo apt-get install smartmontools

After installation you can run the following command to ask the drive to test itself for problems:

sudo smartctl -t long /dev/sda

This process will take some time as the drive will perform tests on every sector of the drive, once the test is complete you can check the results with:

sudo smartctl -l selftest /dev/sda

Should smart testing report a physical error with the drive you might want to give serious consideration to replacing the hardware, once physical sector errors start appearing that are not automatically fixed by the drive internally remapping to spare sectors it is generally a bad sign for the continued longevity and reliability of the drive even if there was some means to work around it.


Panic mode after upgrading to ubuntu 15.10

If you are stuck at a grub prompt, that means that you aren't even booting into Linux. You will either need to reinstall from media, or do some serious technical gymnastics to recover the system.

Having said that, it doesn't mean that your data is lost. During an install, you can attempt to not make the file systems, which is dangerous. Also, you could boot with a live distribution (like the Ubuntu installer) and use that interface to mount your disk and backup to other media. There is no one prescribed way to do this.


Found how to do it. In the left most corner of the taskbar, right click and "Preferences" appears. From here you can change the options.


It seems that ScanTailor fills the gap. It is available under Ubuntu.
I saw a video on YouTube with a ipevo ziggi-hd document camera and  ScanTailor.
Looked very promising to me.


How to remove orange dots in Ubuntu Dock

Open Terminal and run

gsettings set org.gnome.shell.extensions.dash-to-dock custom-theme-running-dots 'false'


How to disable gpg GUI asking for passphrase?

I found an answer on StackOverflow that did the magic. Here's the link: https://stackoverflow.com/a/53641081/1708426


Adding to a file: /etc/udev/rules.d/51-android.rules

if gedit is your editor of choice, from the command line write sudo gedit /etc/udev/rules.d/51-android.rules and add in the lines you want. There are plenty of examples but the main thing that will be individual to you is the vendor and product id found through a lsusb and looking at your device.


This can be done with FFmpeg, although it isn't as quite as simple as using FMLE on Windows.

The short answer is that you use a command like

ffmpeg <commands to read the input>
   -vcodec libx264 -vpre baseline \
   -acodec libmp3lame -ab 32k \
   -threads 0 \
   -f flv "$STREAM_URL"

where $STREAM_URL is the RTMP URL from Ustream, which will include your channel ID and your user key.

Full details are written in this blog post:
http://blog.yjl.im/2011/09/broadcasting-using-x11grabr-and-ffmpeg.html

See also this question: How do I stream to Twitch.tv?


Step-1: Open the terminal and install the following packages.

sudo apt-get install gcc g++ python
sudo apt-get install gcc g++ python python-dev
sudo apt-get install mercurial
sudo apt-get install bzr
sudo apt-get install gdb valgrind
sudo apt-get install gsl-bin libgsl0-dev libgsl0ldbl
sudo apt-get install flex bison libfl-dev
sudo apt-get install g++-3.4 gcc-3.4
sudo apt-get install tcpdump
sudo apt-get install sqlite sqlite3 libsqlite3-dev
sudo apt-get install libxml2 libxml2-dev
sudo apt-get install libgtk2.0-0 libgtk2.0-dev
sudo apt-get install vtun lxc
sudo apt-get install uncrustify
sudo apt-get install doxygen graphviz imagemagick
sudo apt-get install texlive texlive-extra-utils texlive-latex-extra
sudo apt-get install python-sphinx dia
sudo apt-get install python-pygraphviz python-kiwi python-pygoocanvas libgoocanvas-dev
sudo apt-get install libboost-signals-dev libboost-filesystem-dev
sudo apt-get install openmpi*

Step-2: Download the all-in-one tar.gz file from http://www.isi.edu/nsnam/ns/

Step-3: untar it using "tar zxvf ns-allinone-xxx.tar.gz"
Once all files are extracted enter into the directory through the terminal and run "./install". Once installed the terminal will look something like this and will ask you to add some directoties to your PATH environment.

Step-4: PATH is an enviroment variable. Basically, it tells your machine were to search for programs.
Open a new terminal and edit the following file from your home directory using:

"gedit ~/.profile"

find the following line: PATH="$HOME/bin:$PATH"
and add a colon and paste the given directory.... something like this - PATH="$HOME/bin:$PATH:~/Desktop/Cop/ns-allinone-2.35/bin".

Step-5:  Add two more environment variables as shown in the terminal for LD_LIBRARY and TCL_LIBRARY as follows:

export LD_LIBRARY_PATH="~/Desktop/Cop/ns-allinone-2.35/otcl-1.14:~/Desktop/Cop/ns-allinone-2.35/lib"

export TCL_LIBRARY_PATH="~/Desktop/Cop/ns-allinone-2.35/tcl8.5.10/library"

Step-6: Now NS2 has been installed and configured.... to validate it do the following:

cd ns-2.35
./validate

One last step....to start using the network simulator install the following:

sudo apt-get install ns2 nam xgraph

check this blog


The vdb is defined in the manual as follows:

  Prepare Partitions

  The first step in setting up DRBD is to prepare the partitions/disks
  to be used as DRBD devices. We are assuming that we have a disk (vdb)
  on which we will create a partition table, and a primary partition of
  1Gb for the DRBD device.

I suggest you re-read the manual from the top. I guess you will get what they are talking about, if you just take the time to understand it all


I figured it out. Just for the record, in case anyone else has the same problem (using Diodon):

Open the dconf Editor

net
 |-- launchpad
        |-- diodon
               |-- clipboard

makes sure "instant paste" is checked.

It works fine now. Thanks for the help.


if the DVD doesn't work go for usb here's the link for tutorial
http://www.ubuntu.com/download/help/create-a-usb-stick-on-ubuntu

if you are using windows go to

http://www.ubuntu.com/download/help/create-a-usb-stick-on-windows


Xfce4 panel not responding to mouse(touch pad) clicks

I always got the same problem recently with xubuntu 14.04
My temporary solution is to type xfce4-panel -r in a terminal window to restart the panel.


The problem was solved by installing new kernel (4.5)


Try this:

#!/bin/bash

find ${PATH//:/ } -type f -executable 2>/dev/null | while read -r c; do
  ldd "$c" | grep -q -m 1 libX11.so
  [[ ${PIPESTATUS[1]} -eq 0 ]] && echo "${c##*/}"
done

See: man find, help while, help read, man ldd, man grep, man bash


Ubuntu 12.04 (64 bit) ultra laggy Unity-3d with 295.33 and 295.40 drivers on pre G80 series nvidia quadro 3450 card: Guest session seems un-affected

I finally solved the problem.

I deleted my entire ~/.config directory. Logged out and logged back in. Ubuntu 3d now works perfectly with the unpatched 295.33 driver.

I will diff the two .configs to find out what was causing the laggy performance..but my guess is that it was something outisde of compiz since deleting just the compiz entries didnt fix the slowness.


whenever i try to install anything via ppa method,it displays this error at the end.what should i do?

when ever you run apt it tries to finish the incomplete install.
judging from the error, something is wrong with the postscript of the package oracle-java7-installer.

do apt-get purge oracle-java7-installer and the messages will stop.
then you can try to reinstall it or java8 later.


Ubuntu 12.04 update and graphics card update

You need to enable restricted packages in your software sources.
Go to Ubuntu Software Center>Edit>Software Sources

Now select the third option.
Run sudo apt-get update and now try installing fglrx.


There is a 'Recovery Mode' boot option on startup;

  This mode just loads some basic services and drops you into command
  line mode. You are then logged in as root (the superuser) and can
  repair your system using command line tools.

Reference

Unlike a Windows recovery it will not automatically fix any errors - you will need to use command line tools and understand exactly what you are doing to repair your installation.

As Michael K suggested you can also use a live CD to recover an installation but once again you must know what you are doing and use command line tools to carry out the repair. There is a good Ubuntu Documentation page on Live CD Recovery that I recommend you have a read through to get a good understanding of what is required and how to use it.

A third option is to do a re-install of the operating system but do not format and just 'overwrite' your existing installation.

Boot to the install media and go through the install process as usual.
When you get to the partitioner to allocate drive space, depending on the version you are installing check the box marked 'Manually select partitions'  or 'Something else' and click forward. Use the SAME user name and password as the existing account when setting up again.
Find your existing installation and you must UNCHECK all the 'format' boxes and mount the partitions in the same place they are now.

As long as no 'format' boxes are checked, no data will be lost in your home folder and the system files will be overwritten with the originals. You should then complete all system updates again.

Regardless of what option you choose to use to try and recover an installation you should regularly back up your important documents and files so that you can restore them if needed.

Read through the answers to Comparison of backup tools for a comprehensive list of recommendations.


Terminal only outputs last few lines and everything before is deleted

You can pipe the output to a pager like less, or redirect it to a file, and then read the file using your favorite editor or pager.

For example:

grep -R foo ./DIR | less    # search for foo, view a screen full at a time

or:

grep -R foo ./DIR > outputs # search for foo, and output the results to a file

less outputs                # view the file one screen full at a time


Can I get the workspace popup to come up before I move to another workspace?

Unity 3d does show a preview the way you've mentioned. If you're using Unity 2d you can have a better preview, and easier switching between workspaces by pressing Super+S.


How to force youtube-dl to save Opus-encoded audio as *.opus files

If you are looking to keep both the audio file and the video file use -k as one of your arguments. Ex. : youtube-dl -k youtube.com/watch/somevideo if you want to save your audio file as .opus use youtube-dl --audio-format opus youtube.com/watch/somevideo

Some extra notes:
If you want to have the audio be the best you can get it use youtube-dl --audio-quality 0 youtube.com/watch/somevid if you want to have the best quality of audio and youtube-dl -x youtube.com/watch/somevid  to extract the audio directly.  If you want more info on all of this stuff just use youtube-dl -h it will give you the help message and the more you read the less confusing they get.


It seems it isn't compatible with KDE 4.13. I tried to use it on an Arch install and it does not load the transparency effects. I have looked into their repository and didn't see any recent activity to make widget compatible cu KDE 4.13. Latest commits were from 2013-12-18 02:15 pm

You can check here: https://projects.kde.org/projects/playground/artwork/oxygen-transparent/repository


How to update grub after installing Ubuntu 14.04 through MAAS with Global Kernel Parameters?

The reason why the grub config is not updated is because the sudo update-grub command is outputting the changed file to stdout. You need to update the file in /boot with the -o flag.

sudo update-grub -o /boot/grub/grub.cfg


Automatic mounting RAID array which is mounted manually

My mdraid drive is in the /etc/fstab file mounted by UUID, with a note added by the installation:

# / was on /dev/md127 during installation
UUID=a7e381c3-8336-4768-b77b-79faf573dc20 /               ext3    errors=remount-ro 0       1

The UUID matches the one given by the command

blkid /dev/md127

(and not the UUID in mdadm.conf!) so that looks like the way it can be identified for mounting.

By the way, my system has another array that is only exported through iSCSI and not locally mounted - it appears in mdadm.conf but not in /etc/fstab.


Problem Upgrading - Wants to do a Partial Upgrade, Is this safe for my xbmc install?

I don't know for sure if this upgrade can be done safety. If you setup apt-undo you can undo your system upgrade so that in case of disaster rollback is possible.

apt undo

Alternatively you can use portable xbmc from portablelinuxapps.org


Unable to lock the administration directory (/var/lib/dpkg/) is another process using it?

This should be used as last resort. If you use this carelessly you can end up with a broken system. Please try the other answers first before doing this.

You can delete the lock file with the following command:

sudo rm /var/lib/apt/lists/lock

You may also need to delete the lock file in the cache directory

sudo rm /var/cache/apt/archives/lock
sudo rm /var/lib/dpkg/lock

After that, try opening Synaptic again.


This is probably not a Ubuntu specific question, so please have a look at this answer on stackoverflow.

If that code :

#include<stdio.h>
#include<string.h>

int main(){

char str_a[20];

strcpy(str_a,"Hello, world!\n");
printf(str_a);

return 0;}

is really the code you're trying to debug, gcc is probably clever enough
to have simpified your code as printf("Hello world\n"); return 0, or simply use the builtin for strcpy.

So try --no-builtin, perphaps with -O0, it is at least working on gcc (Ubuntu 5.4.0-6ubuntu1~16.04.4) 5.4.0 20160609.

You can use objdump -d prog to see the disassembly of your code, there is no call to strcpy here.

For this question in particular

You're using break 7, but the line is empty, using break 8 should work.


It turns out I had to restart my computer - three times that is. Snap apps are working properly now.


apt Repositories - How to Choose the Right One for Lubuntu

When you need to pick a source that does not support your version number get the one nearest to your version.

Ubuntu names are in alphabetical order so "saucy" would be the newest. Besides that you can also always opt for the one from the newest LTS. That would be 14.04: Trusty.

BUT in this case I would advice to NOT use any of these sources. From the versions they support Saucy is the newest and that has gone end of life a long long long long time ago. It is from 2013 and the least your should aim for is the latest LTS (14.04).

===

See their website and opt for the 'source' install from this location:

http://sourceforge.net/projects/wview/files/wview/wview-install-debian/download

That should download wview-5.21.7.tar.gz and you can do the generic "make/configure". (their is an HTML in the file that has your sources so you probably might have already seen this).


Performance problem Ubuntu 20.04 when sharing screen with discord 0.0.10 and gaming

in my case happened something similar, got it "fixed" by turning off hardware aceleration in discord appareance settings. Now discord got from 30% to 50% of my cpu iddling when sharing screen, but SOMEHOW the OS and videos/games that i share lags less than before. lets say before my fps got from 30 to 12 when sharing screen, now it gets from 30 to 20, so its somehow better, but not as good as windows perfomance, wich i got installed in the same laptop and lags way less, lets say it gets from 35fps to 28.


I'm not sure if it like works, but i've found a semi-completed driver repo. https://github.com/indev29/egis0570
Just give it a try.


It would appear you need to sudo apt-get install firmware-b43-installer

Manpage for Ubuntu: here

additional information from linuxwireless here

Instead of a computer restart, in a terminal issue the following commands:

sudo modprobe -r b43 ssb wl and

sudo modprobe wl

Note: Allow several seconds for the network manager to scan for available networks before attempting a connection.


The python code below is meant to be bound to two different shortcuts.
For example for English, bind Ctrl+Alt+1 to

python /path/to/script us

And for Russian, bind Ctrl+Alt+2 to

python /path/to/script ru

For more info on setting shortcuts, read on Luis Alvarado's answer

While in reality setting input source depends on it a sources index in gsettings array, this script determines each source's index automatically and appropriately sets it

Script source code

from gi.repository import Gio
import sys

def gsettings_get(schema,path,key):
    if path is None:
        gsettings = Gio.Settings.new(schema)
    else:
        gsettings = Gio.Settings.new_with_path(schema,path)
    return gsettings.get_value(key)

def gsettings_set(schema,path,key,value):
    if path is None:
        gsettings = Gio.Settings.new(schema)
    else:
        gsettings = Gio.Settings.new_with_path(schema,path)
    return gsettings.set_uint(key,value)

sources = list(gsettings_get('org.gnome.desktop.input-sources', None ,'sources' ))

index = 0
for source in sources:
    for item in source:
        if sys.argv[1] == item:
           index = sources.index(source)

gsettings_set( 'org.gnome.desktop.input-sources' , None, 'current',index )


After upgrade to 13.04, Screen is flipped - text is left-to-right but upside down

Type gnome-control-center display into the terminal. Then click on rotation and change it to "Normal" or "180 Degrees" which ever is not the current setting. That should fix your problem.


low volume sound even with the volume up to max?

In the upper right side of the screen, you can see a symbol of speaker. Click it. If the volume level is high there, leave it and go to Sound preferences and increase output volume.


Maas Check Power State - Error: Unknown power_type 'ether_wake'

According to the etherwake man page: "etherwake is a program that generates and transmits a Wake-On-LAN (WOL) "Magic Packet", used for restarting machines that have been soft-powered-down (ACPI D3-warm state).

MAAS supports the wake-on-Lan power type. You can add a node in MAAS and choose 'Wake-on-Lan' from the power type drop down menu, and that will give you the same power on capability.

Wake-on-lan only powers on nodes, it does not power off nodes (this the reason for the error). It's a limitation on this power control. Using other power types, such as IPMI, Virsh, etc., will allow you to power on and off nodes.


Rails bundler error installing Nokogiri (1.5.5) and Bundler cannot continue

The answer was to do:

sudo apt-get install libxslt-dev


I wanted to only leave a comment, but I don't seem to have the permissions, so I'm using the answering window instead.

I don't have a full answer, but I'm seeing similar symptoms on a new installation of 12.10. For now, all I can offer is a workaround: when you only see the desktop background, you can press CTRL+ALT+T, which opens up a terminal window. In there, you can install e.g. a very simple window manager, which you can use as a fallback from unity.

sudo apt-get install fluxbox

Then you can kill the gnome-session process, which will effectively kill your whole X session.

pkill gnome-session

You'll get back to the login screen. In the login window, click the ubuntu icon in the login window, and select fluxbox. This will at least allow you to move windows around and have an environment in which you can debug the original problem.

Sorry, but I can't help with the original problem right now.


Login after suspend taking an increasingly long time - 18.10

Try with sudo ln -s /usr/lib/systemd/system/gdm.service /etc/systemd/system/display-manager.service --force, this could fix it.


To transfer the present ubuntu image to other system

You need a program that can produce an iso file, and this is Remastersys.

This set of instructions helped me install and run successfully remastersys on Ubuntu 14.04.1 32bit and also successfully create and use a bootable flash drive with the custom iso I made.

Note: a flash drive works unless you manually upgraded the kernel for some reason before making an iso of your system.

Press Ctrl-Alt-T and run

sudo apt-get install plymouth-x11

Go to this link and download remastersys version for 32bit or 64bit system

http://www.remastersys.com/ubuntu/pool/main/r/remastersys-gui/

IMPORTANT: I downloaded version 3.0.4-1 i386 and it WORKS I checked 3.0.2- version and it doesn't work.

Open Programs and Updates (search in Dash or in the System's parametres)
In Programs and Updates, go to Other tab and press Add...
Copy/paste this

deb http://www.remastersys.com/ubuntu precise main

and press OK

Now look for two lines with "www.remastersys.com/" in the list you can find on the Other tab and make sure you check both boxes. Enter a password if you are asked to.
Press Ctrl-Alt-T and run

sudo -i

apt-get install remastersys-gui

To open remastersys-gui, you always need root priveleges. So do it in the terminal (Ctrl-Alt-T)

sudo -i

remastersys-gui

P.S. Please do some research here on askubuntu because this question has been answered many times before.


You should look in the /usr/share/xsessions/. For me in Ubuntu 16.04, I had  to manually add the awesome.desktop file there.

$ ls /usr/share/xsessions/
awesome.desktop  ubuntu.desktop
$ cat /usr/share/xsessions/awesome.desktop
[Desktop Entry]
Encoding=UTF-8
Name=awesome
Comment=Highly configurable framework window manager
TryExec=awesome
Exec=awesome --no-argb
Type=Application


Unsure why this question hasn't been answered.

Dirt simple.

apt-get install openssl

This will install the latest version of openssl packaged for your Ubuntu version.

You can install higher levels of openssl, doing something like this...

apt-get -y install software-properties-common
LC_ALL=C.UTF-8 add-apt-repository ppa:ondrej/apache2 </dev/null
apt-get update

apt-cache policy openssl

# Now you'll see a higher openssl level... for example...

net10 # apt-cache policy openssl
openssl:
  Installed: 1.1.0h-2.0+ubuntu18.04.1+deb.sury.org+1
  Candidate: 1.1.0h-2.0+ubuntu18.04.1+deb.sury.org+1
  Version table:
 *** 1.1.0h-2.0+ubuntu18.04.1+deb.sury.org+1 500
        500 http://ppa.launchpad.net/ondrej/apache2/ubuntu bionic/main amd64 Packages
        100 /var/lib/dpkg/status
     1.1.0h-2.0+ubuntu18.04.1+deb.sury.org+1 500
        500 http://ppa.launchpad.net/ondrej/nginx/ubuntu bionic/main amd64 Packages
     1.1.0h-2.0+ubuntu18.04.1+deb.sury.org+1 500
        500 http://ppa.launchpad.net/ondrej/php/ubuntu bionic/main amd64 Packages
     1.1.0g-2ubuntu4.1 500
        500 http://ubuntu.mirrors.ovh.net/ubuntu bionic-updates/main amd64 Packages
        500 http://security.ubuntu.com/ubuntu bionic-security/main amd64 Packages
     1.1.0g-2ubuntu4 500
        500 http://ubuntu.mirrors.ovh.net/ubuntu bionic/main amd64 Packages

Notice the highest packaged version for Bionic is currently 1.1.0g + latest stable version (from ondrej PPAs) is 1.1.0h, so adding additional PPAs can provide higher level code.

Caveat: Be sure you know what you're doing. If you add the wrong PPA to your system, you can brick your system (brick - can't reboot or start some essential services). Also some PPAs are safe + others are... questionable...

Be sure you understand what you're doing when you add PPAs to your system.


Unable to create virtual environment with python 3.6

Since you specifically installed python3.6 instead of Ubuntu's default python3 version, which is python3.5, you have to install python3.6-venv instead of python3-venv since that would resolve to python3.5-venv.

To do so, you can use sudo apt install python3.6-venv.


MatLab 2009 installition isssue on Ubuntu 14.04LTS

You need the UNIX version of Matlab, you purchase it on mathworks website. You may be eligible for the student edition, which is cheaper. This is if you really want your own copy of Matlab, but if your uni provides you with computers with Matlab you can save on that and use computers at uni.
There is an opensource, free (you don't pay for it) software for ubuntu (and gnu/linux in general and other *nix systems) which has the same syntax and (basic) functionality as MATLAB. This software is called octave, you can have it on your system by opening a terminal emulator (press Ctrl + Alt + t) and type in sudo apt-get install octave and hit the enter key. Then type in your password, which won't show, neither as bullets nor as stars and hit the enter key. type in y and the enter key if asked for confirmation.
When your get a line which starts again with the dollar symbol $ type octave and the enter key and explore.


How can I get my western digital hd to work?

Smartware does not support Linux and there is absolutely nothing you can use to get it working. This software is aimed strictly at Windows users (and we all know why ;) )

To me this is a possible security risk: it auto mounts by default so should someone get hold of your drive and load malware on that partition you could be setup for some serious problems. If you are only using Ubuntu you can use gParted to remove that software and free up some space that you can actually use.

You might want to look up Déjà Dup or Back In Time as two recent, popular backup programs with graphical interfaces. You will find them in the software repository.


The Sennheiser GSP 350 is a stereo headset (with "virtual" 7.1 Dolby Surround Sound), so it only has 2 audio channels as far as Ubuntu is concerned.  Choose the stereo headset option and the headset may process the audio to feel like 7.1 surround (but of course you won't get true 7.1 surround without actually having 7 different speakers).

You may also want to check out https://help.ubuntu.com/community/SurroundSound for more info


Installing Ubuntu to dual boot with windows 8.1, windows not recognized during install

Read the following thread it's similar to your post and you can also read the documentation on DualBoot not to miss anything.


Cannot find softwares installed via synaptic manager after accidentally deleting sources.list

Ubuntu keeps track of software sources using the sources.list file you have deleted.

  Why older sources file is not working?

Because older list points to software sources compatible with older ubuntu which if installed somehow prone to crash. Never use such approach while upgrading.

Fix for now : Use this site to generate sources.list file for appropriate Ubuntu version.
http://repogen.simplylinux.ch/

then run sudo apt-get update

Have a look in /etc/var/cache/archives . Possibly the packages are there. But you have downloaded the packages for wrong version (11.10) if you used old source files without correct modification. You can just try to install the software. Its possible you have to re download few packages or all packages.  Give a try.


Ubuntu 14.04 server has been compromised

I'd suggest:

Take an image of the server
Start the image of the server in an isolated environment on a computer owned by You
Copy the emails to external storage

If the disks of the server (which contains the emails) aren't part of the server, you might be able to mount the disks from another server, and get access to the emails without having to power-on the compromised server.

Afterwards, you should create a new server (don't use the compromised server any more)


Is it possible to use Juju without having sudo access on local machine?

If you're referring to using the juju client commands (IE, juju deploy, juju bootstrap, etc) None of those commands require sudo at the moment. The new "local" provider for juju will require sudo power, but that's only if you're doing a local LXC deployment.

On the remote side of things, the juju-agent does require and run as root.

I'm not entirely sure how either part of juju would fit in to the shared machine model of c9.io or nitrous.io (Are you going to have those IDEs drive Juju?). If you're looking for integration points with those services, the juju client is set up in such a way that you can do that (have a unique $JUJU_HOME for each user where they can maintain their own environments.yaml, etc). I haven't attempted integration personally but it there shouldn't be too much to change in order to do so.

If you're trying to deploy services to a shared machine as a regular user that likely will not work.


Are there any applications to manage SMS messaging on an Android from Ubuntu?

Try Airdroid, it does everything you want for free !
It is a webserver like KiesAir and very easy to operate SMS communications.

http://www.airdroid.com/


Ubuntu 18.04 Asus Xonar DG sound card not recognized

Alright, it turned out that the card was not properly inserted on a PCIe 16.

I changed the carded to another PCIe 16 slut and fastened the card with a screw, then chosen alsamixer as explained here, and also chosen Analog Output-CM187881 in Sound > Setting as my output, it works like a charm!


can't install software--can I fix missing dpkg?

Test this:

Open a terminal - Press Ctrl+Alt+T

Run it:

sudo -i
mkdir /tmp/dpkg
cd /tmp/dpkg
wget http://security.ubuntu.com/ubuntu/pool/main/d/dpkg/dpkg_1.17.5ubuntu5.2_i386.deb
# or
wget http://security.ubuntu.com/ubuntu/pool/main/d/dpkg/dpkg_1.17.5ubuntu5.2_amd64.deb
ar x dpkg*.deb data.tar.gz
tar xvzf data.tar.gz ./usr/bin/dpkg
cp ./usr/bin/dpkg /usr/bin/
apt-get update
apt-get install --reinstall dpkg


I would try vlc. It is in the standard repos and can be installed easily

    sudo apt-get install vlc

You can get more info from http://www.videolan.org/vlc/index.html


How do I make browsing a Windows network work on Xubuntu?

Note: I do not have your NAS but I have assisted those that do and this is from my notes:

  but there is a Synology NAS which it should see at the very least

It should see it automatically and not under Windows Network but under Browse Network directly but you have to tell Synology to do that. In the Control Panel > File Sharing > File Services > Advanced > Bonjour > Select Enable Bonjour service discovery

Bonjour allows Mac users to discover the NAS in their file manager automatically. Bonjour in Linux is called Avahi and it does the exact same thing. The only thing you need to do on the Linux side is make sure avahi is running:

sudo service avahi-daemon status

If for some reason it's not running start it:

sudo service avahi-daemon start


if you have Grub as bootloader you can check this Question: How do I customize the GRUB 2 menu?

Otherwise you can check BURG

Here a list of Bootloaders

Last but not least check this question Graphical Bootloaders?


Initialize a newly installed program folder structure with bash script

My question is, how do I start firefox and immediately stop it again,
  but still let it create the folder structure?

Give it some time before killing it:

firefox &
sleep 5
pkill -f firefox

This waits 5 seconds before killing firefox. If not enough, increase the time given to sleep.


How to connect with vpnc and wifi at the same time?

try looking at proxychains its a application that routes all the traffic to a specific proxy. since when you connect to the vpn the service routes the whole traffic thru it, maybe browser started within proxychain will not follow the vpn tunnel. this is not really a answer but is a direction to be looking for to solve your problem. proxychains


Try Shutter.

  Shutter is a feature-rich screenshot program. You can take a
  screenshot of a specific area, window, your whole screen, or even of a
  website – apply different effects to it, draw on it to highlight
  points, and then upload to an image hosting site, all within one
  window. Shutter is free, open-source, and licensed under GPL v3.

To install Shutter, just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command(s) below:

sudo apt-get install shutter

Source:Shutter


History command in graphic interface of OS

Each of the programs that you interact with in a GUI typically have their own logs for various things. AFAIK there is no way to find a universal log of everything you do in a GUI like you would with the history command.

Perhaps if you enable debugging in your Desktop Manager you could get additional output, but each program that you interact with will have its own logs somewhere.

If you are using unity, you can learn more about debugging here.


Ubuntu 18.10 Google online account timeout

you may need an App Specific Password from your google acct


Access lenovo ideapad (z580) bios with ubuntu installed

Press and hold F2, then power on. Mine has Windows 8 preinstalled with UEFI boot.


Switch to host desktop from citrix session

Two steps are needed for this.

Press ctrl+F2 in the citrix session. This enables keyboard shortcuts from the host system (Ubuntu).
Now you can use alt+tab to switch the focus to the application you used before opening citrix (or the desktop).


When I plug in earphones or HDMI, I have to manually change the speaker settings

Alright, I think I've got something you can try.
If you search for Multimedia Systems Select on the Dash. Open it and go to the Audio tab, where you can select the default audio Input and Output devices.

This should be installed by default. If it isn't, you can always run sudo apt-get install gnome-media. If it is not shown in the Dash, run:

gksudo gedit /usr/share/applications/gstreamer-properties.desktop. In the resulting text file, go to the line starts with NoDisplay=. Change the NoDisplay=true to NoDisplay=false I had the same problem. Sometimes when I try to change the volume I still have to switch, but my computer always has issues that make zero sense, so I'd still give it a shot. Good luck!


how can i find all files that contain embedded crc32's

I'd agree with Ahmed on many points (use find, use a regex, use posix-extended-mode) but for the implementation. There are a few problems:

find has a case-insensitive -iregex mode  that makes this better by not needing to specify A-Z as well as a-z
Speaking of, CRCs are hexadecimal strings. We only want [0-F]… which I think we can specify as a single range. If it doesn't work, use [0-9a-f]
And we need to check for square brackets (or it'll just match any 8-char string).
-regex and -iregex search the whole path. We need to make sure your string isn't in a directory name so we exclude any slashes after the CRC.

Here's my current best effort:

find -regextype posix-extended -iregex '.*\[[0-f]{8}\][^/]*'

This will allow for extensionless files too.


What is the minimum size for a hard drive to use ubuntu?

Shortly, "yes", however you may run into slow file transferring and other problems due to a small SSD, especially if you intend to be using any large programs, such as games. The bare-minimum required specs that can be found here are as follows:

700 MHz processor (about Intel Celeron or better)
512 MiB RAM (system memory)
5 GB of hard-drive space (or USB stick, memory card or external drive but see LiveCD for an alternative approach)
A display capable of 1024x768 resolution
Either a CD/DVD drive or a USB port for the installer media
Internet access is helpful


Uninstalling Ubuntu is a complex process. But you can simply remove it from your system without any harm in following case. Try this, but be cautious.

Read my blog entry at WordPress for advanced options. Also given below, but still you can refer the other.

Login to your Windows XP. Windows's boot loader is named as Master Boot Record or MBR. While installing Ubuntu after Windows, this MBR will be replaced by Linux Grub. When you remove Ubuntu, Windows has no boot loaders and boot will failure. So what you need to do is to restore MBR. Well, it is not so complicated process with EasyBCD software. You can download it from here. Download and install this software into your machine.

Now open your device manager. From there you need to open disk management window. Wait for few seconds since it requires some time to display disk information. Now you can see your disk's partitions. NTFS refers to Windows and Ext refers to Linux. Simply select on Linux partition and right click on it. Now choose delete partition. Be sure you are selecting and deleting linux partition only. Now your Ubuntu is away from your system. Things are not so ready yet. You need to change this volume into Windows' drive to use it in Windows. Again right click on it and select New simple volume. Follow on screen dialogues and create the new partition.

Now open EasyBCD software. You can see an option BootLoader and choose Install Windows XP boot loader to MBR under MBR options. You are done with. Now close everything and reboot your system.

You can refer EasyBCD's working in this site


Access internal drive when booting from a USB key

Running a system scan fixed (this part of) the problem.

I pressed F12 while the computer was rebooting. An 8-bit menu appeared and I chose the System Scan. This ran for about 15 minutes and detected a problem in the partition table. At the end of the scan, it fixed the problem, and now I can see four disks in the Unity Launcher on the left of the screen.

Now, when I run disks or gparted or execute sudo fdisk -l, I also have access to the 256 GB ssd disk.


How to make a shortcut on my desktop of a file which is located in a dropbox?

In 18.04 click on the Dropbox icon on the top bar and open the Dropbox folder and look for the file you want to place on your desktop.

Having found the file, right click on it and select Copy to... from the drop down menu.

Next step, you will be presented with a dialogue box to indicate where the file is to copied to. Select Desktop

The file will then be added to your desktop as directed.


LAN and wifi not detecting after upgrading to Ubuntu 13.10

You can open up a terminal CTRL+ALT+T and install the broadcom-kernel-source.

sudo apt-get install bcmwl-kernel-source

and then reboot.


How to manually copy home files on hdd from live-usb

I just took the hit and cleaned out the entire pc. Those links are helpful, but for my situation, there was more need to get the pc back up than to spend another day on this.
Lesson understood.. Backup, which is precisely what I am doing right now.


How to show subtitles under the video in VLC?

You probably want to display subtitles below the picture on the black surface?

By default you can only position subtitles inside the picture. That is why when you were experimenting you could not place the subtitles below the picture.

But still there is a way to do what you want using Cropadd video filter.

How to show subtitles under the video in VLC

1) Go to Tools > Preferences and below on the left, in the
    "Show Settings" section, choose "All ":

2) In the left menu choose Video > Filters > Cropadd :

3) In the "Padd " section enter some positive number for the "Pixels to
    padd to buttom " option. For this example I used 75px, you are free to experiment.

NOTE
As was noticed in the comments, with the current settings (75px) there is a tiny green line below the video. The solution for getting rid of that tiny green line is simple: enter some even number (for example 76) and there will be no green line below the video. Thanks for this tip to some anonymous user and the community moderator Grace Note who passed this tip in the comments below.

4) Then, again in the left menu, go to Video > Filters and in the
    "Video filter module " section check the "Video scaling filter "
    option. The result must be that in the text field below the current
    section there will be written "croppadd ".

NB!
There are two "Video scaling filter " options to choose from: one in the left and one in the right column. On of them is for another filter - "Swscale". Choose the one, that will give you the word "croppadd" written in the text field below (see the picture):

5) Click "Save " button:

6) Now, for the changes to take effect, you must restart VLC (close it and run again)

That's it.
This way you can customize the position of subtitles so they will be shown outside the picture .

Showcase

DISCLAIMER:
The following screenshots are taken using videos from the Stanford University's learning course
"Algorithms: Design and Analysis, Part 1".
NOTE: this course has already transformed into "Algorithms Specialization
" as of year 2019.

BEFORE:

AFTER:

Useful tips

It is very helpful to assign the related Hotkeys to manipulate
subtitles position in real time.
Go to Tools > Preferences > Hotkeys and assign some hotkey
combination for the
"Subtitle position up " and "Subtitle position
down". To do this double-click on the related line and choose some key combination. Don't forget to save and restart VLC player for changes to take effect.
For instance I have chosen Ctrl+Alt+UP and Ctrl+Alt+DOWN respectively. So now I can dynamically adjust the position of subtitles by moving them up or down while watching a video.
There are more customization options in the "Subtitles/OSD "
section in Preferences, like changing Font, Font size etc, so
you can fine tune the subtitles settings according to your needs.

UPDATE (May 2015)

As user akcasoy noted in his comment in the latest (as of May 2015) version 2.2.1 of VLC, the name of the required filter was changed from "Video scaling filter" to "Video cropping filter" (which is actually much more intuitive and relevant).

So here a screenshot for the step 4 if you use the currently latest VLC version 2.2.1:


This is caused by the fast startup option on Windows 8+. In order to safely access the Windows hard drive in Ubuntu, you need to turn off the fast startup option in Windows power settings.


First you have to create a file called .hidden in the same directory where you have the files you want to hide.

Then all you have to do is to open that file with a Text Editor and add the names of files to that file, one per line (You can also hide directories with the same method). Then you need to refresh the view.

Also I have made a script for this propose:

source

To see your hidden files press Ctrl+H


Open a Terminal (Ctrl+Alt+t) and type:

dconf reset -f /org/gnome/settings-daemon/plugins/media-keys/

It will restore the default settings for all your media keys.


Source: https://www.maketecheasier.com/6-useful-graphical-git-client-for-linux/

Install the OpenJDK instead of the Oracle JRE, you will find that SmartGit won’t run at all. Here’s the fix:

Download SmartGit.
Extract the tar file to your home folder.
Open a file manager and navigate to the bin folder inside the smartgit directory. Open the smartgit.sh file with a text editor.

Change the line

#SMARTGIT_JAVA_HOME=/usr/lib/java

to

SMARTGIT_JAVA_HOME=/usr/lib/jvm/java-1.6.0-openjdk/jre

At the last line of code, change the line:

$_JAVA_EXEC $_VM_PROPERTIES -Xmx${MAXIMUM_HEAP_SIZE} -Dsmartgit.vm-xmx=${MAXIMUM_HEAP_SIZE} -jar "$SMARTGIT_HOME/lib/smartgit.jar" "$@"

to

$_JAVA_EXEC $_VM_PROPERTIES -Xmx${MAXIMUM_HEAP_SIZE} -Dsmartgit.checkIncompatibleJava=false -Dsmartgit.vm-xmx=${MAXIMUM_HEAP_SIZE} -jar "$SMARTGIT_HOME/lib/smartgit.jar" "$@"

Save the file and close it.

Lastly, click the smartgit.sh file and select Run when prompted.

SmartGit is free for non-commercial use.


Scan for new wireless networks continuously in adhoc mode

Personally i like solutions with GUI, so here is one:

LinSSID - Graphical wireless scanning for Linux


Can't load new project Unity 3D on Linux

Try signing out and signing in again.

I had same problem. I installed beta 5.5.1 and it worked well the first time. But later the above problem occurred.

Later I saw that I was working offline. I connected to wifi and signed in again worked well.


Even 128GB would work for you. I have a 240GB SSD, still have 120GB space left and I do a lot of gaming. It could be a good idea to get a larger HDD for backups and large files though.


Keep getting messages about internal system errors

Potential Reason for These Unreportable Errors

I think I've figured this out.  I think that this particular bug reporting avenue is a hangover from the alpha and beta development stages--when the developers wanted as many bug reports as possible, regardless of whether the user was willing to file a full launchpad bug report or not.  Once 12.04 was released, the developers no longer wanted anonymous bug reports so they disable this ability.  They only want bug reports that the user themselves manually takes the time to file.

This is understandable but I would consider it a bug that apport/ubuntu-bug is presenting the user with non-actionable information.  When development stops and they no longer want a high volume of bug-reports turning off automatic bug reporting is one thing, but leaving the user without a path (at the very least a link) to report to launchpad, and without a way to save the information contained within the bug report should be rethought.

My Solution to Non-Actionable Error Reports

I know what I am going to do next time I get one of these unreportable/unsavable errors.  I'm going to take a screenshot of the window, run apport-bug apport and file a bug saying that apport should not present the user with non-actionable information.  At the very least the user should be able to save the report for their own use or for manually reporting a bug.

How to Proceed Regarding your GPU Bug

As for your problem, apport was running a script to debug GPU problems.

If you aren't actually noticing problems with your GPU other than these error messages I'd say you can safely ignore them.

If you are seeing any weird graphics related behavior, keep an eye on your logs--specifically xorg.0.log and syslog, but maybe the kernel logs as well.  If you are noticing errors copy them down, and try to make a best guess (or ask) whether it is a driver problem, kernel problem or X11 problem.  Then use apport to file the bug against what you determine to be the best package (for example for my nvidia driver I would enter apport-bug nvidia-current-updates), be as detailed as you can be in the resulting bug report and put the symptoms you experience and any errors you noticed into the description when you file the bug.  More information about filing bugs is here and here.  Good luck.


"upgrade" from ubuntu 15.10 to ubuntu GNOME 15.10

In general, yes. As long as you don't reformat the partition containing /home, a reinstall should leave your files alone.

However, as noted in Zacharee1's comment, it's almost certainly better to just

apt-get install ubuntu-gnome-desktop


Preventing interface from becoming default route

Don't set a gateway IP for the storage network interface.

The adding of a gateway adds a route of a default route over that gateway.  If you don't set the gateway, the only route added is the route for that specific IP subnet to its own range and nothing else.

That will prevent the system trying to go out to other resources over that storage subnet that has no uplink beyond its own subnet.


revert to older version of the default video player

You can check what versions are available to you with sudo apt-cache madison ^packagename

Replace "packagename" with the package you're trying to downgrade.

Then, sudo apt-get remove packagename

Then install the package with the version you want:

sudo apt-get install packagename=1.2\*

Replace the version number with the one you want. Using the \* is a wildcard for subversions. Or you can copy the entire version from the list that the first command gave you.


Stuck on boot ubuntu 18.04 5.3.0-59-generic

Boot to Recovery Mode, if required.
Edit /etc/default/grub:
sudo -H gedit /etc/default/grub
or
sudo pico /etc/default/grub
Find:
"quiet splash"

Change it to:
"quiet splash acpi_backlight=vendor"

Or:
"quiet splash acpi_backlight=video"

sudo update-grub
reboot


Automating a daily displacement of files bearing dates in their names

You've (understandably, as it is quite strange) slightly misunderstood bash's quoting syntax. In general, you need to put double-quotes around "$variables" (so that spaces don't break scripts) -- but if you put quotes around wildcards*, it will just take them literally. They have to be unquoted to work. That's why mv is being asked to move a file which actually has * in its name. (Normally when you use *, bash replaces it with a list of files, before passing it to mv.)

Unfortunately trying to collect a list of files into a variable has even more quirks, so I'd recommend this time just not using one for $datedTodayfiles.

It would be easiest to just go order=$(mv "$actualFolder/$today"_* $todayFolder).

Also:

watch out because $todayFolder probably isn't being set to anything and $actualFolder seems to be the wrong thing.
you probably don't really want to chmod 777


File ownership changes on save for "some" files

It sounds like the file is actually being deleted and recreated. I doubt photoshop is doing any kind of chmod'ing in the background.


Intel Sandy Bridge no sound through HDMI

I remember logging in and logging out after plugging in the HDMI device and changing the sound settings to HDMI Output seemed to help in my case.

Additionally, running 'alsamixer' in terminal seemed to have made a difference before.


Compiz cube not working with 12.04 in gnome classic or unity

Note that the switcher icon in the launcher will always show 2x2, regardless of your actual workspace layout.

The Compiz Cube is designed to work only with horizontal one-dimensional workspace layouts, not the default 2x2 Ubuntu Unity layout; changing to a 1x4 (1 vertical, 4 horizontal) workspace layout should fix it.

To make that work:

Open CCSM, go to General, and set the workspace layout to 1x4:

Now disable Desktop Wall and enable the Desktop Cube and Rotate Cube plugins.
The default cube transition speed can be so fast that it looks like a plane. To adjust, you can tweak the Additional Settings in the Rotate Cube plugin
After enabling all this, reboot!

Here's a Youtube video showing the cube fully functional with 4 workspaces on one monitor. The applications are Firefox, Synaptic, Terminal and Software Center, one on each workspace.


How to make visible shares only for specified users

The purpose of the $ in a share name is to make it invisible, what you are  looking for is a "Mapped Drive", which could be done in one of these two ways

If the clients are in a domain environment you would set up a GPO (group policy object) that applies to specific groups, This link should help

If the clients aren't in a domain environment you will need to write a simple script that the users click every day (or when they can't access it) you can see examples at this stackoverflow question


Should all Ubuntu Touch apps use a MainView?

Headers and toolbars are part of the MainView, so you would have to implement that yourself if you don't use MainView.

Also the MainView has an "ActionManager" which is needed for actions from the app to become available to the HUD. Other properties that we need (for example for application switching) such as an AppID may also be added to the MainView.

So it is highly recommended to use the MainView, even if you don't use headers or toolbars. I can imagine that some special apps (games?) would not be using MainView, but then you may end up implementing functionality of MainView yourself. Of course this is possible (since MainView and all related classes are open source), but it is something that is hard for us to support.


Xsetwacom Top and Bottom values for Wacom Bamboo Fun 6X8?

If the default values aren't correct then please report this as a bug here:

https://bugs.launchpad.net/ubuntu/+source/xf86-input-wacom/+bugs

To fix your issue right now, you could try trial and error until you get it working.


Vi/Vim

Just use vim or vi which offers file encryption with blowfish when using -x option.

create a file for encryption as follows:

vim -x filename.txt

Then it will prompt to enter encryption key

Enter encryption key:

Once a file has been encrypted by Vim once, you never need to use the -x option when opening that file again. Vim will automatically recognize it as an encrypted file and do the right thing.

Because Blowfish is a symmetric key encryption system, the same key is used for both encryption and decryption. When Vim opens a file for the first time with the -x option, the first thing it will do is ask you to give it a key you can use to encrypt and decrypt the file, with this prompt:

Need encryption key for "abc.txt"
Enter encryption key:

After entering the key, you will then be asked to confirm the key, to ensure you did not mistype it.

Enter same key again:

Then it will open as normally as usual.

Read more here

CryptoTE

According to the website.

CryptoTE is a text editor with integrated strong cryptography.
It is based on the popular Scintilla widget and automatically stores
text data in secure encrypted container files.
Compared to other "password keeper" programs, CryptoTE does not force
any structure upon your data: it works with plain ASCII text
and does not require you to fill in grids, key-value attributes,descriptions etc.
Encryption is transparently performed using the
highly-secure Serpent cipher. The editing interface is thoroughly
optimized for speed and ease of use.
Multiple subfiles, Quick-Find and a two-click random password generator
make daily use very convenient.

for ubuntu see.


Yes, but you have to enable it manually by adding the discard option to your /etc/fstab like so:

/dev/mapper/faldara-natty /               ext4    discard,noatime,errors=remount-ro 0 1

Also the purpose of TRIM is to prevent a decrease in write throughput of the drive after much use, not to prevent it from wearing out.  I have been using a drive for over a year without TRIM and have yet to suffer any performance loss, so IMHO, it is much ado about nothing.


What is the name of the icon for usb drives in Ubuntu?

Using the function list_icons():

icons=icon_theme.list_icons()
for icon in icons:
    if 'usb' in icon:
       print icon

and the output:

drive-removable-media-usb
usbpendrive_unmount
gnome-dev-removable-usb
usb-creator
drive-harddisk-usb
gnome-dev-harddisk-usb
gnome-dev-unknown-usb
usb-creator-gtk
drive-harddisk-usb-symbolic

Now take your pic


Error loading shared libraries: libstdc++.so.6

You need to install corresponding packages manually by

wget http://archive.ubuntu.com/ubuntu/pool/main/g/gcc-10/libstdc++6_10-20200411-0ubuntu1_i386.deb
sudo dpkg -i libstdc++6_10-20200411-0ubuntu1_i386.deb

wget http://archive.ubuntu.com/ubuntu/pool/main/g/gcc-10/libstdc++6_10-20200411-0ubuntu1_amd64.deb
sudo dpkg -i libstdc++6_10-20200411-0ubuntu1_amd64.deb

and then you will be able to run

sudo apt update

and

sudo apt install --reinstall libstdc++6 libstdc++6:i386 libapt-pkg6.0
sudo apt install command-not-found apt-file


Actually, it does indeed default to ext4. Ubuntu has used ext4 as the default for quite some time now.

If you're having filesystems mounted as ext2, there was likely a problem with the installation, or perhaps a problem with your hardware.


Is there a simple way to add exFAT support?

Ubuntu 14.04 and 14.10 (13.10 and higher)

Adding additional ppas is no longer required. Also, it seems fuse-exfat is no longer installable. The package to install is now named exfat-fuse and is available by default (universe repository). The package exfat-utils will also add the usual filesystem management tools including this package. Also thanks to this answer

sudo apt-get install exfat-fuse exfat-utils

Ubuntu 12.04 (13.04 and lower)

A more detailed, step-to-step description on how to use the PPA pointed to by StalkerNOVA can be found on stackoverflow, copied here for the sake of completeness:

Do only once:

Add the repository: sudo add-apt-repository ppa:relan/exfat
Update the package list: sudo apt-get update
Install the exfat package: sudo apt-get install fuse-exfat
Create the mount folder: sudo mkdir /media/exfat

Everytime you want to access sdxc the card/exfat filesystem:

Mount the filesystem (replace sdc1 with your exfat partition): sudo mount -t exfat /dev/sdc1 /media/exfat
On some devices, cameras, for locked sdxc cards etc you might want to mount the filesystem read only, just add -o ro to the mount command line: sudo mount -t exfat -o ro /dev/sdc1 /media/exfat
Read and write to /media/exfat to your heart's desire.
When you are done, unmount the filesystem: sudo umount /media/exfat

The sdc1 in the step-by-step above refers to the linux device where your card/exfat filesystem resides on. If this changes (usb card readers, cameras) or you simply don't know which one it could be either use the menu system System -> Administration -> Disk Util and usually you will find your camera or card reader in the list on the left hand side. Or - as a quick shortcut - use cat /proc/partitions on a terminal command line. The latter is only useful if you know all the other unchanging device names on your system and thus can quickly identify the one added one.


How to change the name of Guake terminal?

this is discussed here. But I can recommend you to use Tilda terminal. I switched from Guake to that, for more customization options.


You'll need xrdp together with x11vnc if you want remote access to your Unity desktop.

First, install xrdp and x11vnc:

apt-get install xrdp x11vnc

Then edit /etc/xrdp/xrdp.ini and make sure it contains at least the following:

[globals]
bitmap_cache=yes
bitmap_compression=yes
port=3389
crypt_level=high
channel_code=1
max_bpp=24

[xrdp1]
name=Remote Desktop
lib=libvnc.so
username=ask
password=ask
ip=127.0.0.1
port=5900

Restart xrdp for the changes to take effect:

/etc/init.d/xrdp restart

Now open up a terminal window (Ctrl+Alt+T) and set up a VNC password (you don't want to leave wide open access to your desktop from the internet):

x11vnc -usepw

You'll be prompted to set up a password, that will be used for RDP authentication.

The last step is to start x11vnc. There are tons of options that you can use, but here is an example to get you started (run this in the same terminal window you just opened):

x11vnc -rfbauth ~/.vnc/passwd -display WAIT:0 -reopen -nevershared -forever -wirecopyrect always -scrollcopyrect always -norepeat -1 -xkb -capslock -skip_keycodes 187,188 -bg -o ~/x11vnc.log &

The & at the end will leave x11vnc running the background, so you can close the terminal window and leave it running.

You'll need to add this command to your startup scripts if you want x11vnc to run automatically after a reboot.


Try simulating the command without doing anything else, in order to get only the command's error messages:

sudo apt update
apt install --simulate build-essential manpages-dev

If there are no error messages, try running the commands as root without the --simulate option.

sudo apt update
sudo apt install build-essential manpages-dev


How can I make Google Chrome use flat theme icons for open close expand buttons?

To make Google Chrome use the system them, Follow these steps.

Open Chrome And click on the hamburger icon (settings)
Go to Appearance.
Select the "Use GTK+ theme" option
Relaunch Chrome

That's it.

If you want the buttons to work on window mode too, right click on the top bar of the Chrome window and select the option "use system title bar and borders".


"kvm disabled by bios" when installing in a Packard Bell

The "kvm disabled by bios" error is a know error and according to this page you should be able to fix your problem by enabling it in the bios

  "KVM: disabled by BIOS" error
  Check if there is an option to enable it in the BIOS. If not, look for a more recent BIOS on the vendor's web site.

  Note:

  On some hardware (e-g HP nx6320), you need to power-off/power-on the
  machine after enabling virtualization in the BIOS.

  Enabling some BIOS
  features may break VT support on some hardware (e-g Enabling Intel AMT
  on a Thinkpad T500 will prevent kvm-intel from loading with "disabled
  by bios")

  On some Dell hardware, you also need to disable "Trusted
  Execution", otherwise VT will not be enabled.

if that doesn't work try re-installing you linux (comment if that does not work either)


Reduce network utilization disable update manager and so on

You can configure update manager to look for updates more unfrequently or even disable de automatic updates doing the following.

Open update manager.
In the lower left you will find the "Settings ..." Button click on it.
Go to the "Updates"tab, there you will find some check boxes and some combo boxes. The first combo box has the label  "Automatically check for updates" and you can choose there the frequency for ubuntu to look for new updates.

You can even set it to "Never" and then you will have to check manually for updates. This is a non recommended configuration from the security point of view, but if your bandwidth is limited ...

Check also for applications like Ubuntu One, Dropbox or some other cloud sync applications which may consume your bandwidth.
Also some facebook.twiter.twenty clients may be looking for new posts and messages too much frequently.
Also check if you have an email client configured to download the emails.

Hope this helps

P.S.: Sorry for the long explanation but I can not upload pictures


Here is ansver: http://ubuntovod.ru/ask/discussion/58/ne-rabotaet-ctrl-a-v-ubuntu-11.10

In eng: run gnome-tweak-tool, "theme", and change key theme. This:

Hope i help somebody. :)


apt-get install proxy problem: no such file or directory

Some of your variable assignments have spaces after the =. There should be no space. They should look like:

PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games"
http_proxy="http://proxy.iiit.ac.in:8080:"
https_proxy="http://proxy.iiit.ac.in:8080:"
ftp_proxy="http://proxy.iiit.ac.in:8080:"
no_proxy="localhost,127.0.0.1,localaddress,.localdomain.com"
HTTP_PROXY="http://proxy.iiit.ac.in:8080:"
HTTPS_PROXY="http://proxy.iiit.ac.in:8080:"
FTP_PROXY="http://proxy.iiit.ac.in:8080:"
NO_PROXY="localhost,127.0.0.1,localaddress,.localdomain.com"


Task Switcher brings all windows of an application to the front

When doing ALT+TAB, you have the list of applications at the top and the list of the windows of each application underneath. When you just browse to a particular application and let go, it will bring all windows to the front. If you select the application and then use ALT+ to select a particular window, then only that window will be brought to the front.

Since you usually have some configuration issues when initially switching to Gnome from Unity (I usually have to install gnome-tweak-tool and then switch from the Unity-specific theme, enable the minimize/maximize buttons, etc..), I don't think I was getting the list of windows initially. I think they'd have popped up if I lingered on an application for a second (Unity behavior, at least), but I usually try to avoid that; Unity's behavior is to just switch to the last window of an application when you ALT+TAB to an application but not to a specific window.


Show all open windows / Activities overview in Ubuntu 18.04 GNOME - how to disable some ways to produce it?

You're using the 'Activities Configurator' GNOME shell extension evident from the screenshot. To work properly the extension needs the 'Activities Overview Hot Corner' option in Tweaks turned on.

So launch Tweaks and enable the 'Activities Overview Hot Corner' option. Then go to the 'Extensions' section and open the settings for Activities Configurator. Disable the 'Activities Overview Hot Corner' option from here.


How to run a golang restful api as service in ubuntu server

You can build the go binary and create a systemd service to run it as a service.
sudo nano /lib/systemd/system/go_app.service
Use the following example for the .service config.
[Unit]
Description=My example go application
[Service]
Type=simple
Restart=always
RestartSec=5s
ExecStart=/opt/go_app
[Install]
WantedBy=multi-user.target

Source: https://www.atpeaz.com/running-go-app-as-a-service-on-ubuntu/


Installing Ubuntu 18.04 Only & Along Side Windows 10

The order of partitions would generate a negligible boot  in performance while giving you an excellent chance to corrupt your partitions or get GRUB very confused. It's installed? It works? Good as it gets.


How can I know which machine Juju is actually using?

Doing a juju status will show you all the machines running. It depends on which commands you run:

juju destroy-service <service-name>

will destroy only the service. You probably want either:

juju destroy-unit

or

juju destroy-machine

To clean up what you have you probably can do a juju status, see which machines are not assigned to services, and then destroy those by referrring them by number, like: juju destroy-machine 3 as an example.

All of these are documented here:

https://jujucharms.com/docs/stable/charms-destroy


Generate a public key out of the private key you have there (if you don't have it yet) and determine the key type:

ssh-keygen -y -f /path/to/private/keyfile

This will output something like ssh-rsa AAA[...] (for RSA type) or ssh-dsa AAA[...] (for DSA type).
Put the private key as a file in ~/.ssh/id_rsa (if RSA type) or ~/.ssh/id_dsa (if DSA)
Put the public key in place - essentially the same as in the first step, but redirecting the output.

ssh-keygen -y -f /path/to/private/keyfile > ~/.ssh/id_rsa.pub

Replace rsa with dsa if needed.
Fix the permissions (optional, SSH client may complain if not set appropriately):

chmod 600 ~/.ssh/id_rsa
chmod 644 ~/.ssh/id_rsa.pub
chmod 700 ~/.ssh

Again, replace rsa with dsa if needed.

The ~/.ssh/id_rsa and ~/.ssh/id_rsa.pub paths are default locations where the OpenSSH client looks for keys. You can set your own location, though, by setting this in your client configuration file, e.g. in ~/.ssh/config.

Host *
IdentityFile /path/to/myprivatekey


Parallel and wget to download and generate ordered numeral filenames

Here is a basic idea:

i=0
for url in $(grep -v '#' "$1") ; do
  ((i++))
  wget --output-document="file"$(printf "%03d" $i) "$url"
done

I have no experience with parallel, but this seems to do the job:

i=0
for s in $(grep -v '#' "$1") ; do
  ((i++))
  parallel --no-notice -n0 wget --output-document="file"$(printf "%03d" $i) "$s" ::: {1..1}
done

These scripts expect the list file as an argument on the command line.


Win7 host, Ubuntu 13.04 guest: VirtualBox 4.2.14 seamless mode loses Ubuntu launcher

That is exactly the expected behaviour of "seamless" mode where we only want to display the application windows of a guest OS on the host desktop:

  With the "seamless windows" feature of VirtualBox, you can have the windows that are displayed within a virtual machine appear side by side next to the windows of your host.Virtual Box Manual

We should not run seamless mode for a Ubuntu/Unity guest where the application menu was integrated in the top bar (Unity default) and will not be accessible in seamless mode.

To have access to the application's menu from seamless mode with Unity in the guest we may want to remove the packages responsible for the globalmenu:

sudo apt-get remove appmenu-*
sudo apt-get remove firefox-globalmenu  # for Firefox


Single Card Draw & infinite Redeals in AisleRiot's version of Klondike?

I bumped into the reason for this change in behaviour on a German site.

Previously you could edit the value of max-redeal near the beginning of the config file and set it to -1 for unlimited redeals (as per the comment for that line). In Ubuntu 12.04 that no longer works. The code that parses the options in the new Klondike menu item, forcefully resets the value of max-redeal.

There may be a more elegant way to do this, but the simplest way I found was to edit as root (use sudo) the file:

/usr/share/aisleriot/games/klondike.scm

Near the end of the file, look for a section like this:

(define (apply-options options)
  (set! deal-three (cadr (list-ref options 1)))
  (set! deal-one (cadr (list-ref options 2)))
  (set! no-redeal (cadr (list-ref options 3)))
  (set! max-redeal (cond (no-redeal 0)
;            (deal-one 2)
             (#t -1))))

Either delete, or comment out with a semi-colon, the second to last line.


SAMBA on exFAT partition, can't have write permissions

Try this:

Open a terminal,Press Ctrl+Alt+T

Run it:

exec sudo -i
apt-get update
apt-get dist-upgrade
apt-get install --reinstall exfat-fuse exfat-utils
chmod -Rf 777 /media/Movies


Video Card not detected in Steam on Wine

I will start my answer saying, I maybe wrong. But, I looked at your Device ID in PCI database. But, There's no card for 0x423. But 8300 GS's ID is 0x0423. So, I think this is a counterfeit card. Please install this card under Windows with a Driver Downloaded on NVIDIA's official site. If the offcial driver (download from nVidia site only) can be detected with your your card, you are safe. (don't use drivers that came with your card.) I know this because it happened to me. Most counterfeit cards use fake IDs that close to actual card. (in this case 8300 GS, not 610GT)

Maybe I'm wrong.


Have you installed any Gmail or Google add-ons to your Firefox lately?

Here are some things you might want to do in order to narrow down the possible causes:

Start Firefox on Safe Mode https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode
Disable one by one your add-ons https://support.mozilla.org/en-US/kb/disable-or-remove-add-ons
Unpin the tab and then re-pin it


Is there no support for microphone recording in Flash Player for linux?

Adobe Flash Player for Linux is at version 11.2.202.261, while you've been trying to install an older version. Either use the Software Center to install it, or run

sudo apt-get update && sudo apt-get install adobe-flashplugin

In case you wish to use the Flash Player provided by the Ubuntu partner repository, remove the tar.gz installation first. There is no way to update it, and the two will not work together.

How do I install Adobe Flash player?

As for the microphone problem, you should ask Adobe, if there "no support from Adobe".


The answer here worked for you according to the comments.

I would normally include the essential parts of the answer to avoid linkrot, but since this is on another Stackexchange site that won't be an issue.


How can I get Gnome3 to remember my session?

Unfortunately, the ability to save the session has been removed due to a bug.

That said, I rarely have the necessity of this functionality, as long as I am the only user of a computer thanks to suspend / and or hibernate (and to never switching off my working place desktop).


I found the solution for the original problem (no video on browser) and later (Ubuntu upgrade fail) on my Oracle VM running Ubuntu:
1- No video on browser: After trying all video configurations, it occurred to me that Audio is also part of the system. I change the Audio controller in the VM settings to SoundBLaster and the problem was solved.
2- Ubuntu upgrade fail from 18 to 20: the new release of Oracle VM solved the problem. Probably Oracle's bug was fixed.


How can I resize a filesystem to fit a bigger partition?

Yes, resize2fs is correct. You give it the name of the partition as its only argument, and it will look up the current size of the partition and extend the file system to that size.


Ubuntu blocked by current security policy, solution inside Ubuntu rather than in BIOS

Secure boot won't allow an OS through if its bootloader isn't signed with a key it likes, which of course are only Windows ones for most manufacturers. Since 12.10 Ubuntu has supported secure boot using a recommended Microsoft key paired with a SHIM loader, but it sounds like something has corrupted in grub's verification with this. I would personally just recommend not using secure boot with Linux as it can cause problems when installing third party drivers (and it's technically been compromised anyways!), but if you'd still like to, you can try repairing grub with boot-repair:

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

Use the "advanced options" and choose your OS and drive with grub as opposed to the auto-repair, which will install grub to every MBR it finds. If it can't repair on its own, you may have to manually sign grub's bootloader using these instructions.


How can I get German language in Evolution for Ubuntu 16.04?

Evolution is a Gnome program. So if you are using Evolution in a Gnome-foreign distro (e.g. Kubuntu), it is likely that the needed language pack for Gnome programs is not installed. (In my case, the document viewer Evince also didn’t have an interface in my language, since it is also a Gnome program.)

Thus, you need to install the above mentioned language pack. You can do this e.g. via the terminal by typing (for your “German case”)

sudo apt install language-pack-gnome-de

If someone wants a different language to be supported than German, then he/she/it has, of course, to change the letters after the last hyphen (e.g. to “it” for Italian).

If you are not sure what exactly the ending for your language is – or for any other reason – you can also install the package via a graphical package-management program like Synaptic. There, just search for “language-pack-gnome”, choose the package you need, and apply the changes (install it).

You have to re-open the program for the changes to be applied.


Ubuntu with 2 static IP interfaces gets 2 default routes

Although I had configured a static address which was being applied to the interface, the system was still running DHCP (see /var/lib/NetworkManager/dhclient*) and populating the default route (as well as the DNS servers).

I fixed the problem by removing the interface and all associated config then adding the interface but connected to a vlan with no dhcp rebuilding it (ticking all the relevant checkboxes in nmtui). I now only have one gateway - but there are still issues with the second interface.


Microsoft doesn't support graphical programs on WSL.

Bash on WSL is intended for running command-line programs that developers might need, but it's possible to run graphical Linux desktop programs on Windows using the Bash shell.

To be more precise, you'll be able to display graphical programs running in WSL on a Windows 10 desktop by using an X server which runs on Windows 10.


Some laptops are known to cause trouble when they are used with linux. If you could provide more information about your computer (manufacturer, model, BIOS version) it would be very helpful to find a solution for your problem.


File operations freeze when putting files larger than 10MB on an SD card

More information is needed about your hardware. It happened to me too. The speed of your processor also contributes to the speed of transferring files.

Check your RAM and swap space. Before this, I had 2GB of RAM.  After I upgraded it to 4GB of RAM, copying files was faster and smooth.  You also need to have large of swap space.

I transferred 200GB file from HDD to my Ubuntu 13.04. The larger the file, the slower it gets. UPGRADE! Just my experience.


My system settings for baltusaj:

The Graphics section was updated from:

sudo apt-get install mesa-utils

But it should work anyway as per default