archlinux: annoying missing icons

I had a fresh install of Archlinux running GDM with Gnome and Xfce.
After installing a couple of apps (Firefox and Chrome) the icons were missing in the menu entries.

By running the below command as root and restart, the issue is fixed.

# gtk-update-icon-cache -t -f /usr/share/icons/hicolor


References:
- https://bbs.archlinux.org/viewtopic.php?id=129988

archlinux - virtual machine essential

Some applications (e.g. Firefox, SDDM) requires the video driver to be installed when running in a VMware virtual machine:

xf86-video-vmware


References:
- https://wiki.archlinux.org/index.php/VMware/Installing_Arch_as_a_guest#VMware_Tools_versus_Open-VM-Tools

The dream is over

For the last 3 weeks I was involved in a series of phone interviews for a job position in a famous company in the Netherlands. My level of confidence was increasing after each interview. The last interview was the toughest one, that included video conference with the IT team and several technical questions with coding on the go, together with a business question.

archlinux / gdm - execute commands at initialization

In order to execute commands at the beginning of the X user session - before the window manager is started -  the xprofile file can be used. The xprofile file is similar in style to xinitrc.

Firstly, create the file ~/.xprofile if it does not exist already. Then, simply add the commands for the programs you wish to start with the session.

References:
- https://wiki.archlinux.org/index.php/xprofile

archlinux - touchpad driver

In my old Presario V3000 the touchpad was working after installation, however the behaviour was a bit strange: the sensitivit was too high and when touching the cursor change the position on screen, like the touchpad area is related to a fixed position on screen.

To resolve this, the synaptics driver was installed.

# pacman -S xf86-input-synaptics

Then perform the configuration:

"The primary method of configuration for the touchpad is through an Xorg server configuration file. After installation of xf86-input-synaptics, a default configuration file is located at /usr/share/X11/xorg.conf.d/70-synaptics.conf. Users can copy this file to /etc/X11/xorg.conf.d/ and edit it to configure the various driver options available."

Example of configuration file with some common options, including vertical, horizontal and circular scrolling as well as tap-to-click:

/etc/X11/xorg.conf.d/70-synaptics.conf

Section "InputClass"
    Identifier "touchpad"
    Driver "synaptics"
    MatchIsTouchpad "on"
        Option "TapButton1" "1"
        Option "TapButton2" "3"
        Option "TapButton3" "2"
        Option "VertEdgeScroll" "on"
        Option "VertTwoFingerScroll" "on"
        Option "HorizEdgeScroll" "on"
        Option "HorizTwoFingerScroll" "on"
        Option "CircularScrolling" "on"
        Option "CircScrollTrigger" "2"
        Option "EmulateTwoFingerMinZ" "40"
        Option "EmulateTwoFingerMinW" "8"
        Option "CoastingSpeed" "0"
        Option "FingerLow" "30"
        Option "FingerHigh" "50"
        Option "MaxTapTime" "125"
EndSection

Alternatively, the Graphical tool "GPointing Device Settings" can be installed to provides graphical on the fly configuration for the pointing device

# pacman -S gpointing-device-settings

References:
- https://wiki.archlinux.org/index.php/Touchpad_Synaptics#Installation

archlinux - tricky wifi configuration

For some reason I cannot explain, the wireless adapter in my old laptop Compaq Presario V3000 gets both Soft and Hard blocked. As a result, the connection to a wireless access point is not possible either using # wifi-menu or # netctl.

The solution:

1. Check whether the wireless lan is blocked:

# rfkill list


2. In case it is hard blocked, then unblock it:

# rfkill unblock wifi

3. Run the wifi-menu, connect to the wlan and generate the profile (/etc/netctl/<profile_name>)

4. Make the netctl auto start at boot:

# netctl enable <profile_name>

To run all these commands, maybe it's necessary to install some packages:

- rfkill
- wpa_supplicant
- wpa_supplicant_gui
- iw
- wireless_tools
- dialog


References:
- https://wiki.archlinux.org/index.php/Wireless_network_configuration#Rfkill_caveat

ubuntu 16.04 LTS - old crap cheap USB mouse issue

I've been testing several linux distributions in my old laptop - HP Pavilion dv6 - and I was stuck with one curious case involving an old crap cheap USB mouse.

During ubuntu installation (running live cd) the mouse works just fine, no problems whatsoever. It can be plug - unplugged many times and it just works. However, after completing the installation on the hard disk and boot, the USB mouse no longer works.

After looking into this matter in google, the solution was to remove gnome-software package, which is related to the ubuntu software center.

Another possible solution was:

# sudo rmmod usbhid
# sudo modprobe usbhid

However it is just a temporary solution and must be executed after reboot, for example.


References:
- https://bugzilla.redhat.com/show_bug.cgi?id=1277837
- http://askubuntu.com/questions/763511/usb-mouse-not-working-after-installing-ubuntu-16-04-persistent-fix
- http://askubuntu.com/questions/763511/usb-mouse-not-working-after-installing-ubuntu-16-04-persistent-fix
- http://unix.stackexchange.com/questions/95842/how-can-i-see-dmesg-output-as-it-changes
- http://www.cyberciti.biz/faq/rhel-redhat-centos-kernel-usb-reset-high-speed-ehci_hcd/