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How is divine loop constructed.

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We can see that the construct tests for their condition at the top of a loop and it keeps looping.

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As long as that condition is true that means as long as the exit status of condition returns zero.

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Usually we are using dialup in cases it's the number of Roop repetitions is not known beforehand.

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Now we can see an example of a vial which is really stupid but easy to explain in that condition.

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We are asking if a name variable is different from saying stop.

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If yes then the existence of those test square brackets of that condition is zero.

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That means that the script will execute commands between do and damn keyboards.

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So it will ask you for your name and assign to a variable name and then the loop is done and we are

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starting from the beginning.

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We didn't condition is your name different from stop.

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If yes continue it.

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Body of vital.

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So you will be looping till you enter stop as if we have C-style for you.

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We also have C-style a while loop.

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Here we are of writing condition into double parentheses and vote is important to mention inside the

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double parentheses.

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You cannot use dollar sign symbol using variable.

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It is similar.

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As for command a lot.

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In the example of the C condition variable A is less than how they meant create file an income and value

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of variable a so this code vote create nine files for us.

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If it out to that condition equal sign that means if a variable A is less or equal to limit then the

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code would create 10 files.

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One of the most common usage of a WHILE loop is for reading files.

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The structure is following.

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We are starting to violate followed by variable which represents one line from the file between do and

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keyboard.

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We specify what we want to do with deadline and now what is most important After down damn keyboard.

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We need to specify what file will be used as a source for standart input of a while loop.

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So basically we are redirecting file into Vinal loop standart input.

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We can also read the file line by line using another method or supply file as a standard input to while

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loop using pipe.

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If you want to write to screen line by line we would do that in the following way.

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So we have discussed already.

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So let's write some script to see it in action.