[Intranet] Yasuhiro ABE, The University of Aizu. | About ThinkPad (Client Environment)

1. Client environment

In the seminar room, we provide ThinkPads with Xubuntu installed for your work.

OS: Xubuntu (an LTS distribution with the lightweight Xfce desktop environment instead of Ubuntu’s default Gnome3)
Packages: ibus, language-pack-ja, docker, kubectl, etc.

For network information, such as IP addresses, see the Network Configuration page.

This computing environment (including the ThinkPads in Seminar Room 10) is personally managed by Abe.
Please report any problems immediately after you log in.
(e.g., missing home directory, missing applications, questions about how to use the system, etc.)

2. How to log in

On the Xubuntu login screen, select "Other…" and enter your AINS ID and password in the same way as in the exercise room.

3. How to start the application

Launch common applications, like a web browser or terminal, from the menu in the top-left corner of the screen.

3.1. Starting a Terminal

A terminal is in the menu by default.

To find other terminal applications, type "terminal" in the search bar at the top of the menu.

4. How to check available commands

Some operations require root (administrator) privileges. Use the sudo command to run these operations.

## See which commands you can run with sudo
$ sudo -l

You can also use sudo to read files that are only accessible by the root user.

$ ls -l /etc/sudoers
-r--r----- 1 root root 779 May  2  2018 /etc/sudoers
$ sudo cat /etc/sudoers

5. Main customization method

You can access most settings from the main menu.

Alternatively, you can type a word like "mouse" in the search bar to find specific settings.

5.1. Adjustment of screen brightness

To adjust the screen brightness, hold down the Fn key and press the F5 (dim) or F6 (brighten) key.

The Fn key is located in the lower left corner of the keyboard.

5.2. Mouse Operation (Touchpad and TrackPoint)

By default, both the touchpad and TrackPoint are enabled.

In the "Mouse and Touchpad" settings screen, you can enable or disable them, change the cursor speed, etc.

The figure below shows the TouchPad disabled.

The TrackPoint is easy to use with practice. Adjust the "Acceleration" setting to a speed that is comfortable for you.

5.3. Resolution setting

The ThinkPad x270 and t430(s) models support Full HD (1920x1080) resolution. If the screen feels too crowded, or if the text seems too small, you can change the resolution in the display settings.

5.4. Setting Up Japanese Input

This section explains how to set up the Japanese input method.

5.4.1. Step 1: Select the Input Method System

Open the "Language Support" menu and set the "Keyboard Input Method System" to IBus.

5.4.2. Step 2: Add a Japanese Input Engine

Open "IBus Preferences". Go to the "Input Method" tab and click "Add".

Find and add "Japanese - Mozc". (Mozc is compatible with Google Japanese Input).

5.4.3. Step 3: Remove Other Input Engines

After adding Mozc, it’s a good idea to remove other engines like "English - English (US)" from the list to avoid confusion.

5.4.4. Step 4: Activate the New Settings

To apply the changes, you must log out and log back in. A full reboot is not necessary.

5.4.4.1. How It Works (Technical Details)

Logging out and back in updates the necessary environment variables (GTK_IM_MODULE, XMODIFIERS, etc.) for all applications. This is why a simple logout/login is the easiest way to enable the new input method. The main environment variables are:

export CLUTTER_IM_MODULE=ibus
export GTK_IM_MODULE=ibus
export QT_IM_MODULE=ibus
export XMODIFIERS=@im=ibus

5.4.5. Customizing Mozc for an English Keyboard

Since Ubuntu 24.04, ibus-anthy is no longer available, making Mozc the primary Japanese input method.

Mozc’s default keybindings are designed for a Japanese keyboard. To easily switch between English and Japanese input on an English keyboard, you need to customize the keymap. This guide shows how to use the F12 key to turn the Japanese IME (Input Method Editor) on and off.

5.4.5.1. Step 1: Open Mozc Settings

To change Mozc’s behavior, use the "Mozc Settings" application.

First, select "Mozc Setup" from the application menu.

Next, click the "Customize…" button to edit the keymap.

5.4.5.2. Step 2: Assign a Toggle Key (F12)

Next, we will assign the F12 key to activate and deactivate the Japanese IME.

In the Keymap editor window, select "Edit" > "New entry".
A new, empty row will be added at the bottom of the table.
Create the first two entries as shown below. This tells Mozc to turn the IME on (Activate) or off (Deactivate) when you press F12.

Mode	Key	Command
DirectInput	F12	Activate IME
PreComposition	F12	Deactivate IME

Mode

Key

Command

DirectInput

F12

Activate IME

PreComposition

F12

Deactivate IME

For better usability, we will add one more function. This will switch the input mode back to Hiragana if you press F12 while you are in the middle of a composition. This is just an example; you can choose any key and command that works for you.

Mode	Key	Command
Composition	F12	Set input mode to Hiragana

Mode

Key

Command

Composition

F12

Set input mode to Hiragana

Your final configuration should look like this:

If the new key binding doesn’t work immediately, log out and log back in.

5.4.5.3. Basic Mozc Keybindings

While the Japanese IME is active, you can use the following function keys to switch between character types:

F6: Hiragana (default)
F7: Katakana (full-width)
F8: Half-width
F9: Alphabet (full-width)

Please try these to see how they work.

6. Technical Overview of the UNIX Input System

(This section is optional and provides a technical background on how input methods work in UNIX-like systems.)

In UNIX, the input system is made of several layers. This makes it very flexible.

+---------------------+
|  Conversion Engine  | <-- Converts keystrokes to characters (e.g., Anthy, Mozc, SKK).
+---------------------+
|    Input Method     | <--- Manages the user interaction (e.g., ibus, fcitx).
+---------------------+
| Desktop Environment | <-- Provides the text boxes in applications (e.g., Xfce, Gnome, QT).
+---------------------+
|        X11          | <-- The basic graphical system that draws windows and text.
+---------------------+

Unlike Windows or macOS, you can mix and match different applications at each layer. This guide focuses on using the ibus Input Method with the Mozc Conversion Engine on the Xfce Desktop Environment. For more advanced configurations, such as using a special input method inside Emacs, you will need to consult expert documentation. This typically involves setting environment variables like XMODIFIERS to prevent conflicts between the main system’s IME and the application’s internal IME.

7. Other Customizations

7.1. Swapping the CapsLock and Control Keys

Some users prefer to swap the CapsLock and Control (Ctrl) keys. Here are two ways to do this.

7.1.1. Method 1: Using the `xmodmap` Command

This is the most universal method for X11 and works on any Linux distribution, including the CentOS terminals in the university exercise rooms.

The man xmodmap command provides the following example for swapping Caps Lock and the left Control key.

!
! Swap Caps_Lock and Control_L
!
remove Lock = Caps_Lock
remove Control = Control_L
keysym Control_L = Caps_Lock
keysym Caps_Lock = Control_L
add Lock = Caps_Lock
add Control = Control_L

Save this text into a file named ~/.Xmodmap in your home directory. The spaces at the beginning of the lines are important and should be kept.
Run the xmodmap command with the new file as an argument:

$ xmodmap ~/.Xmodmap

This will swap the keys. Running the command again will swap them back.

In our seminar room environment, the ~/.Xmodmap file is loaded automatically at login, so you only need to do this once. (For details, see the /etc/xdg/xfce4/xinitrc file.)

7.1.2. Method 2: Using the Xubuntu Keyboard Application

You can also use a GUI application to change this setting.

Note: This method is specific to the Xubuntu desktop and will not work on the CentOS terminals in the exercise rooms.

Open the "Keyboard" application from the main menu.
Go to the "Layout" tab.
Click "Ctrl key’s position" and select "Swap Ctrl and Caps Lock".

8. Troubleshooting

8.1. Keyboard Symbols are Incorrect

If you press the [ key but get a @ symbol, your keyboard layout is likely set to Japanese instead of US English.

Temporary Fix

Run the following command to immediately switch back to a US layout:

$ setxkbmap us

Permanent Fix

Open the "Keyboard" application from the main menu.
Go to the "Layout" tab.
If "Japanese" is in the "Keyboard layout" list, click the "Add" button and select "English (US)".
Select the "Japanese" layout from the list and click the "Remove" button.
Make sure "English (US)" is the only layout in the list.