The /etc/inittab file is one of the most important files on a Linux (and UNIX) operating system. It is read when the Linux /sbin/init program starts your system. The /etc/inittab file lists what programs to start depending on the run level. Provide a sample syntax (id:runlevels:action:process) of an /etc/inittab entry as follows: id = identify your entry runlevels = specify that the process will run at run levels 3 and 5 Action = specify how to treat the program to the init program Process = provide your own name, including any input or output redirection You must start a thread before you can read and reply to other threads.