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Will come to this lecture about Alk. great oak we can take our scripts to next level as you will see

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later.

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But what is an org.

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It is a program that searches files for lines that contain certain patterns and then performs operation

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describe in all body on line with that button.

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Or we can use awk to perform some operation on the chosen line.

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And now we can see basic structure of all.

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It is pretty simple.

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We are starting with keyboard awk.

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Then we specify what operations we want to happen on each line of specific files.

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And what is the structure of that operations you would like to execute for each line.

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It is divided into three parts.

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First section is BEGIN section and everything you type here will be executed before performing operations

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on each line of a specific file.

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Next section is the most important one.

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This section will be executed for each line of specific file and the last section ISDE and section despiser

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is executed after org processed all lines of a specific file.

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Here is some examples how the code looks like.

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Notice that we don't specify file names here but instead we want the awk program to be run just for

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a specific line for specific output of each month.

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So what is happening here.

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Firstly output of eco command is used as an input into our program.

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Then the org executes commands in the BEGIN section then commands in main they are performed for output

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of eco command.

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And finally because we don't have more lines more inputs the N.S. is better from we can of course use

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only one section of our program as we can see here.

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Here we don't have BEGIN and END section we only performing the main section for specific output from

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eco command in awk program best features doesn't work.

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And what's more important if we are using a completely new language in all body for example we don't

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use eco but mainly we are using print command.

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We have also different structure of if our statement and the same is for for loop and many more and

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more is also new for us.

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If we have completely new features available we can call for specific lines.

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For example we have here variable an F which represents number of fields.

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Then we have an R which represents number of records and so on.

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I can feel that this short arc summary may sound hard and difficult for you but please check for following

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lectures where we will focus on each part of all programming and you will find it quite easy.

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We're going step by step.