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This article will explain in detail how the R1-008 Shell environment variable is, and the content of the article is of high quality, so the editor will share it with you for reference. I hope you will have some understanding of the relevant knowledge after reading this article.

Typically, each process has its own "environment", which is made up of a set of variables that contain information that the process may need to reference. In this case, Shell is no different from a normal process.

Each time a Shell starts, it creates a Shell variable that suits its environment variable. If you update or add a new environment variable, the Shell will immediately update its own environment, in other words, the changed or added variables will take effect immediately, and all subsequent generated shell child processes will inherit the environment.

If a script wants to set an environment variable, then you need to export' these variables, that is, you need to notify the local environment of the script. This is what the export command does.

A script can only export variables to the child processes generated by the script, that is, it can only work on the commands and processes generated by the script. If the script is called from the command line, then the variable that the script locks export does not affect the command line environment. That is, a child process cannot export variables to affect the environment in which its own parent process is generated. However, when the script is executed with the source command, because there is no child process, the export command in the script will affect the environment of the parent process.

About R1-008 Shell environment variable is shared here, I hope the above content can be of some help to you, can learn more knowledge. If you think the article is good, you can share it for more people to see.

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