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In this lecture We'll talk about how to count for size using our program.

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I will switch to eat this directory as there are many files I can print the content of directory using

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ls l command record files are starting with Desch in the first column.

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Things are starting with our character and directories starting with letter D.

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So leakin using that.

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No separate files from links and directories.

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So now let's print only file I was using.

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Command C'mon.

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So in our search pattern we will use a regular expression for starting with Desch

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and we see only regler files listed here.

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Great

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now we would like to display files of specific extension so we are using pipe up out both of our previous

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command as an input into another awk program that will search for files ending with extension dot com.

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Don't forget to use backslash before dot revise dot would be represented as any character and not as

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edit and visi only files with conflict engine.

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Now try to use some extension which doesn't exist.

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We don't see an output printed but vote is an exit status

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it is zero even awk.

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Didn't find anything.

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But in our script it would be good to know according to exit status if some extension was found or not

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for that reason we can use grep command.

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So just rename and remove slushes

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we don't see any output printed and exit status.

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Is it this number one good.

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So that means that if grep didn't find bottom biddable exit with a non-zero status.

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Now just for being sure let's search using gap for extension that exists.

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And now check exits tattles.

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Now it is zero.

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Great.

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So using grep.

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If he can tell if extension exists or not in specific location.