im-launch

im-launch [options] [command]

-h, --help
    Display help message and exit.

-v, --verbose
    Print verbose output during execution.

-l, --log
    Write log messages to a file.

--xim-off
    Disable the X Input Method (XIM) server.

--disable-gsettings
    Do not use GSettings for IM configuration.

--input-method=IM
    Specify the input method to use (e.g., 'ibus', 'fcitx').

im-launch is a fundamental utility on Linux systems, designed to properly set up and launch an input method (IM) framework, such as IBus or Fcitx, for a user's graphical session. Its primary purpose is to enable users to input characters for various languages, especially those requiring complex input methods like East Asian scripts or emojis. It plays a crucial role in internationalized computing by ensuring that applications can correctly handle diverse text input.

Upon execution, im-launch typically detects the preferred input method configured through tools like im-config. It then starts the necessary input method daemon (e.g., ibus-daemon) and, critically, sets various environment variables. These include XMODIFIERS, GTK_IM_MODULE, and QT_IM_MODULE, which inform graphical applications (GTK, Qt-based) about which input method module to use. This command is frequently invoked automatically during the desktop environment's startup or through login scripts, making input methods seamlessly functional across all compatible GUI applications and ensuring a consistent input experience.

im-launch heavily relies on the system's im-config setup for determining the default input method. Incorrect configurations, especially involving multiple input method frameworks, can lead to input issues or conflicts. Proper locale settings are also essential for its correct functioning. The environment variables set by im-launch are critical; if they are overridden or not correctly propagated, applications may fail to use the input method.

im-launch is typically executed automatically by display managers or desktop session startup scripts (e.g., from /etc/X11/Xsession.d/ or within GNOME/KDE session startup). Users rarely need to run it manually.

Key environment variables set by im-launch include XMODIFIERS (specifies the XIM server), GTK_IM_MODULE, and QT_IM_MODULE (which tell GTK and Qt applications which IM module to load). These variables are fundamental for proper input method functionality.

im-launch emerged as a versatile wrapper to manage various input method frameworks, notably IBus, which gained prominence as a successor to older systems like SCIM. IBus itself was developed by Google and became a default choice for internationalized input in many Linux distributions, making im-launch a crucial part of the modern Linux desktop's internationalization stack, providing a consistent launching mechanism across different IMs.

ibus-daemon(1), im-config(1), locale(1), setxkbmap(1)