How to make a root file system using busybox

BusyBox is a very popular embedded Linux system tool that integrates many common Unix commands into a small executable file. The general steps to use BusyBox to create a root filesystem are as follows:

1. Download BusyBox: You can download the source code from the official site (https://busybox.net/).

2. Compile BusyBox: Configure the downloaded source code and compile it. Configuration can be done by running make menuconfig. Then run maketo compile BusyBox.

3. Install BusyBox: Run make installInstall BusyBox. _installThis will generate a file tree containing the BusyBox binary and all links in the target directory (which is the default ).

4. Create a basic directory structure: BusyBox only creates a few basic directories by default. You may need to add some additional basic directories, such as /proc, /sys, /mntetc.

5. Create device nodes: Create some basic device nodes /dev/below , such as console, null, ttyetc. This can mknodbe done using the command.

6. Settings /etc/inittaband /etc/fstabfiles: These two files are used to set the initialization tasks of the system and the mount point of the file system respectively.

7. Create other files you need, such as network configuration files, system initialization scripts, etc.

8. Pack the root file system: Finally, you can use tarcommands or other tools to package the entire file directory into a root file system image. The specific packaging method depends on the needs of your target platform, which may be cpio, tar, ext2/3/4, jffs2/squashfs and other formats.

This process may also require some customization based on your actual needs. For example, you may need to add some specific drivers or perform some specific configurations on Busybox. If you need to add other applications to the root file system, it is generally compiled as a static link (if possible) and then added to the appropriate directory in the Filesystem.