[LINUX] Let's clear the ambiguity of the hyphen (-) of the su command now! !!

First of all, from the review

The command to switch from the current user to another user on Linux is su. By the way, this is an abbreviation for ** substitute user **. (Reference: su (Unix) --Wikipedia) substitute means "use instead". The technique of changing only Pokemon is also called a substitute in English. It's not an abbreviation for switch user or super user.

How to use commands

$ su [-] <user name>

The basic command usage is as above, and if you do not specify a user name, you will be super user (root).

What does a hyphen mean?

The - in the su command means to inherit environment variables. In other words, adding - is the same as logging in as that user from the beginning.

• $ su - anotherUser --Inherit environment variables --It will be the same situation as logging in as another User from the beginning
• $ su anotherUser --Do not inherit environment variables

at the end

I wonder if such a simple post is good once in a while