BusyBox init

BusyBox has a minimal init program that uses a configuration file, /etc/inittab, to define rules to start programs at boot up and to stop them at shutdown. Usually, the actual work is done by shell scripts, which, by convention, are placed in the /etc/init.d directory.

init begins by reading /etc/inittab. This contains a list of programs to run, one per line, with this format:

<id>::<action>:<program>

The role of these parameter is as follows:

• id: This is the controlling Terminal for the command
• action: This is the conditions to run this command, as shown in the following paragraph
• program: This is the program to run

The actions are as follows:

• sysinit: Runs the program when init starts before any of the other types of actions.
• respawn: Runs the program and restarts it if it terminates. It is typically used to run a program as a daemon.
• askfirst: This is the same as respawn, but it prints the message Please press Enter to activate this console to the console, and it...