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Changing variable values for a session.

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So now now let's see how the changing variables value as not adhered to.

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His side's variable contains the value of the number of commands to store in the history file.

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Sometimes you won't want your system to save past commands, perhaps because you don't want to leave

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any evidence of your activity on your own system or the target system.

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So in that case, you can set the his size variable to zero.

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So the system will install any of your past commands because this variable has a single value to change

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it, you assign it a new value in the familiar way here.

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So he's size here.

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Uh, his size, for example.

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Zero.

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And so we assigned it now when you try to use up here, up and down arrows to, uh, wrinkle your comments,

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nothing happens, happens because the system no longer stores them here, as you can see, and nothing

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happens here.

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So this is stealthy, although it can be inconvenience.

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So I will change this to one thousand back.

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So we're making variable value chains permanent, so we are watching an environment variable that change

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only occurs in that particular environment.

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In this case, the environment is the best shell station.

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So this means that you when you close the terminal here, for example.

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So when you close the terminal.

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Um, any chance you made are lost.

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So we were able to set back to their default, so for example, his size one, as you can see in the

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last months, is not working.

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When they closed that and open it again, for example, as you can see here, we can see ours.

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Yes, I see it.

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So now we will, uh, change in permanently so.

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If you want to make the changes permanent, so you need to use the export command.

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So this command will export a new value from your current environment.

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This is the best shell to the rest of the system, though, making it available in every environment

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until the oil change and export it again.

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So variables are strings.

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So if you run on the country's side, it's it isn't a bad idea to say the contents of a variable to

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it takes one before you modify it.

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So, for example, since we were about to change, the P is one variable, uh, which controls the information

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we will display in the prompt.

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So the first run, the command to save the existing files to have NEG text while in the current user's

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home directory.

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So Echo here is size and then, uh, this is them.

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This means our home directory and the value of our own value of my keys is that the exterior?

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Oops!

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I actually write and exploit it, so we don't need expert.

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So unless unless you can see the value of my, his size is here.

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So let's read it with cat common value of my his size.

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As you can see, there's a 1000 right at it, so we can open it with MOSFET as well.

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Uh, here.

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Well, the off my side, as you can see it, let's open it.

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And as you can see, there is a one thousand year.

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So let's close it.

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I will show more examples this way you can always undo your changes if you want to be ever more catalyst

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to create a text file with all the current settings, you can save the output of the said commonplace

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text file with command like this, for example, set up here the value of all and, for example, time

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or oh, let's write our party at eleven forty nine here.

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Eleven forty nine and texting.

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So let's open it again, or we can add value of all, as you can see, and we printed all of these variables

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here.

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We can open it with our text for you as well as you can the value of files I can see here we have almost

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two hundred thirty eight lines of these set files.

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So now that he says, variable is still be set to zero when you live this, uh, environment and international

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environment, if you want to raise it here, let's actually change it first to here.

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Uh, clear, clear and export Keast size here.

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So now that he says variable was said, uh, to zero.

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So when you leave this environment and the interim environment, if you want to raise it to his size,

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uh, to variable to one thousand, simply enter this, for example, um, his his size as in one thousand

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and then export his size.

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So this court will set your his side's variables value to one thousand.

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And export it to all your environments here.