Menuconfig


make menuconfig is one of five similar tools that can configure Linux source, a necessary early step needed to compile the source code. make menuconfig, with a menu-driven user interface, allows the user to choose the features of Linux that will be compiled. It is normally invoked using the command make menuconfig; menuconfig is a target in Linux Makefile.

History

make menuconfig was not in the first version of Linux. The predecessor tool is a question-and-answer-based utility. A third tool for Linux configuration is make xconfig, which requires Qt. There is also make gconfig, which uses GTK+, and make nconfig, which is similar to make menuconfig.
All these tools use the Kconfig language internally. Kconfig is also used in other projects, such as Das U-Boot, a bootloader for embedded devices, Buildroot, a tool for generating embedded Linux systems, and BusyBox, a single-executable shell utility toolbox for embedded systems.

Advantages over earlier versions

Despite being a simple design, make menuconfig offers considerable advantages to the question-and-answer-based configuration tool make oldconfig, the most notable being a basic search system and the ability to load and save files with filenames different from “.config”. make menuconfig gives the user an ability to navigate forwards or backwards directly between features, rather than using make config by pressing the key many, many times just to navigate linearly to the configuration for a specific feature.
If the user is satisfied with a previous .config file, using make oldconfig uses this previous file to answer all questions that it can, only interactively presenting the new features. This is intended for a version upgrade, but may be appropriate at other times.
make menuconfig is a light load on system resources unlike make xconfig or make gconfig, which utilizes GTK+. It's possible to ignore most of the features with make config, and doing so makes it more likely that one will configure an incomplete or oversized kernel. It's recommended to start with the .config file included with Linux distribution, which makes it easier to configure a custom kernel.
Better than editing the .config by hand, make menuconfig shows the descriptions of each feature, and adds some dependency checking. With make oldconfig, dependency checking can be done in one step, but requires the user to locate the features that were changed, by hand, to be sure that the needed ones are still enabled.
Practically, using both make menuconfig and make oldconfig, diff, provides the most flexibility and most dependability. Configuring Linux is a significant labor, so users are strongly advised to make backups of it.
The help information is distributed throughout the kernel source tree in the various files called Kconfig.

Dependencies

To use make menuconfig, Linux source is a requirement, a make tool, a C compiler, and the ncurses library.

Key strokes

Symbols

To the left of the features is the setting enclosed in two punctuation marks.
SymbolMeaning
< >No dependencies.
A dependency requires this to be compiled-in, or not compiled.
A dependency requires this to be a module or compiled-in.
- -A dependency requires this to be compiled-in.

Note that the supplied dependency information is primitive, it does not tell you the names of the depentant features.
SymbolMeaning
--->Use to expand this branch as a new window.
Unstable/lesser code, beware.
An option not in an older version of Linux.
An option that will be removed in future versions.

menuconfig in the kernel-build workflow

The user is encouraged to read the Linux , since there are also many other make targets. Each will configure the kernel, but with different features activated, or using a different interactive interface; such as tinyconfig or allyesconfig.

simple (but effective) workflow

  1. make menuconfig
  2. Next build the compressed kernel and its modules, a long process. make.
  3. Install using your favorite method such as make modules_install, make install.