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Today, we will continue our best scripting lessons.

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Let's talk about for loops today for Loop is a programming statement in general that allows our code

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to be repeatedly executed.

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For instance, we run a certain Unix command five times or even 100 times.

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The syntax of for loop is simple.

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We start with the word for in the name of our variable.

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This variable might store an incremental number that we want to use in our script, or maybe it will

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store an output of some command like we did before.

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It really depends on how you want to use your loop.

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Let's start with a simple example and see how we can use for Loop to print a number one through 10.

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In this example, we started with the word for fall by variable, which is then inside the curly braces,

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we have two numbers separated by two dots.

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The first number is our starting number.

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The second is our last number we want to reach.

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We can also add another two dots with a third number, which will be our incrementing number, but by

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default it should increment by one.

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After that, we read the word do Undun and between them is our code block that we want to execute.

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Let's run our program.

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We can also create our counter Lexy style.

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Let's take an example in this example, we are using a variable name C and we initialize it with the

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value of one.

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Then we test it, see less than or equal five.

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And finally, C++ means increment C by one.

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So basically, this problem will start from one increment each time until the number is greater than

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five, which is six.

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And then it will stop.

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Let's run the script.

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Nice.

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Now, let's take a practical example for those, let's spend the first five IP addresses in our twenty

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four subnet.

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Nice.

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Can we now ping each IP with the ping command?

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Let's try that.

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But to make it a little faster, we will send only one packet using the Dachsie argument.

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Nice, but the output is so messy.

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Can we clean it a little bit as you see it from the up with the only I.P. address that replied back

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is one nine to the one sixty.

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That's zero that for if we look at this line, we notice that it's the only one has a string bytes from

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in it.

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Can we use grep to filter our output to show me the line.

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Let's try.

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We can't even make it cleaner by adding if statement after this fine to check of the result of this

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line is true or false.

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Basically, we're checking if the grip command was able to find the strength bites from or not to check

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the result of the previous command.

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We use the dollar sign question mark.

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Let's try that.

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Perfect, we we have we are still getting our output from the drip command, can we hide it?

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Let's suppress it by redirecting it to DEVE No.

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Much better.

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Let's take a look at a different example, assuming that we have many files in our current directory.

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We only want to look for and delete certain files.

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Can we do that using best scripting and.

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Let's try it.

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In this script, we will start with full loop again, but this time we will store the output of the

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command elements in our C and D variable.

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Then we print this variable, which it holds the content of our directory.

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Let's run it.

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Nice, let's talk now for a file called Delete Me and then delete it.

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That's from the command now and see if you can see this file.

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Nice we were able to do with this file.

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We have reached the end of this lesson.

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Thank you.

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And see you in the next one.