21st: Process Architecture in the Linux operating system

Objective

In Linux, an executing program is often made up of a variety of processes, in addition to parent-child relationships, and other relationships. Depending on these relationships, all processes form a whole, providing a complete service to the user (taking into account the terminal, which is the interaction with the user).

This article describes the process structure in Linux in detail.

Process structure

Described in order to provide users with a full service (need to process user IO, etc.) involved in a complete process structure, several parts explained as follows:

　　1. Control process

The process of establishing a terminal connection is called a control process (one of the background process groups)

　　2. Foreground Process Group

The process group that controls the terminal (processing such as the CTRL + C CTRL+D command). The foreground process group can have only one.

　　3. Background Process Group

Process group that handles background transactions. A background process group can have many.

Summary

As mentioned above, the so-called "to provide users with a full service (need to process a variety of user IO commands) involved in a complete process structure", there is a dedicated to describe------session.

21st: Process Architecture in the Linux operating system