Mastering Linux Kernel Development

exit

Every process must end. Process termination is done either by the process calling exit() or when the main function returns. A process may also be terminated abruptly on receiving a signal or exception that forces it to terminate, such as the KILL command, which sends a signal to kill the process, or when an exception is raised. Upon termination, the process is put into exit state until the immediate parent reaps it.

The exit calls the sys_exit system call, which internally calls the do_exit routine. The do_exit primarily performs the following tasks (do_exit sets many values and makes multiple calls to related kernel routines to complete its task):

• Takes the exit code returned by the child to the parent.
• Sets the PF_EXITING flag, indicating ...