Interactive Kconfig interfaces

There are two interactive configuration interfaces available for exploring the available Kconfig options and making temporary changes: menuconfig and guiconfig. menuconfig is a curses-based interface that runs in the terminal, while guiconfig is a graphical configuration interface.

Note

The configuration can also be changed by editing zephyr/.config in the application build directory by hand. Using one of the configuration interfaces is often handier, as they correctly handle dependencies between configuration symbols.

If you try to enable a symbol with unsatisfied dependencies in zephyr/.config, the assignment will be ignored and overwritten when re-configuring.

To make a setting permanent, you should set it in a *.conf file, as described in Setting Kconfig configuration values.

Tip

Saving a minimal configuration file (with e.g. D in menuconfig) and inspecting it can be handy when making settings permanent. The minimal configuration file only lists symbols that differ from their default value.

To run one of the configuration interfaces, do this:

  1. Build your application as usual using either west or cmake:

    Using west:

    west build -b <board>
    

    Using CMake and ninja:

    mkdir build && cd build
    cmake -GNinja -DBOARD=<board> ..
    ninja
    
  2. To run the terminal-based menuconfig interface, use either of these commands:

    west build -t menuconfig
    
    ninja menuconfig
    

    To run the graphical guiconfig, use either of these commands:

    west build -t guiconfig
    
    ninja guiconfig
    

    Note

    If you get an import error for tkinter when trying to run guiconfig, you are missing required packages. See Install Linux Host Dependencies. The package you need is usually called something like python3-tk/python3-tkinter.

    tkinter is not included by default in many Python installations, despite being part of the standard library.

    The two interfaces are shown below:

    menuconfig interface
    guiconfig interface

    guiconfig always shows the help text and other information related to the currently selected item in the bottom window pane. In the terminal interface, press ? to view the same information.

    Note

    If you prefer to work in the guiconfig interface, then it’s a good idea to check any changes to Kconfig files you make in single-menu mode, which is toggled via a checkbox at the top. Unlike full-tree mode, single-menu mode will distinguish between symbols defined with config and symbols defined with menuconfig, showing you what things would look like in the menuconfig interface.

  3. Change configuration values in the menuconfig interface as follows:

    • Navigate the menu with the arrow keys. Common Vim key bindings are supported as well.

    • Use Space and Enter to enter menus and toggle values. Menus appear with ---> next to them. Press ESC to return to the parent menu.

      Boolean configuration options are shown with [ ] brackets, while numeric and string-valued configuration symbols are shown with ( ) brackets. Symbol values that can’t be changed are shown as - - or -*-.

      Note

      You can also press Y or N to set a boolean configuration symbol to the corresponding value.

    • Press ? to display information about the currently selected symbol, including its help text. Press ESC or Q to return from the information display to the menu.

    In the guiconfig interface, either click on the image next to the symbol to change its value, or double-click on the row with the symbol (this only works if the symbol has no children, as double-clicking a symbol with children open/closes its menu instead).

    guiconfig also supports keyboard controls, which are similar to menuconfig.

  4. Pressing Q in the menuconfig interface will bring up the save-and-quit dialog (if there are changes to save):

    Save and Quit Dialog

    Press Y to save the kernel configuration options to the default filename (zephyr/.config). You will typically save to the default filename unless you are experimenting with different configurations.

    The guiconfig interface will also prompt for saving the configuration on exit if it has been modified.

    Note

    The configuration file used during the build is always zephyr/.config. If you have another saved configuration that you want to build with, copy it to zephyr/.config. Make sure to back up your original configuration file.

    Also note that filenames starting with . are not listed by ls by default on Linux and macOS. Use the -a flag to see them.

Finding a symbol in the menu tree and navigating to it can be tedious. To jump directly to a symbol, press the / key (this also works in guiconfig). This brings up the following dialog, where you can search for symbols by name and jump to them. In guiconfig, you can also change symbol values directly within the dialog.

menuconfig jump-to dialog
guiconfig jump-to dialog

If you jump to a symbol that isn’t currently visible (e.g., due to having unsatisfied dependencies), then show-all mode will be enabled. In show-all mode, all symbols are displayed, including currently invisible symbols. To turn off show-all mode, press A in menuconfig or Ctrl-A in guiconfig.

Note

Show-all mode can’t be turned off if there are no visible items in the current menu.

To figure out why a symbol you jumped to isn’t visible, inspect its dependencies, either by pressing ? in menuconfig or in the information pane at the bottom in guiconfig. If you discover that the symbol depends on another symbol that isn’t enabled, you can jump to that symbol in turn to see if it can be enabled.

Note

In menuconfig, you can press Ctrl-F to view the help of the currently selected item in the jump-to dialog without leaving the dialog.

For more information on menuconfig and guiconfig, see the Python docstrings at the top of menuconfig.py and guiconfig.py.