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This article mainly introduces the relevant knowledge of how to use the next command in awk, the content is detailed and easy to understand, the operation is simple and fast, and has a certain reference value. I believe you will gain something after reading this article on how to use the next command in awk. Let's take a look at it.

The next of awk is equivalent to the role of continue in the loop, and the statements that follow the next will no longer be executed.

To understand how it works, let's analyze food_list.txt, which looks like this:

Food List ItemsNo Item_Name Price Quantity1 Mangoes $3.4552 Apples $2.45253 Pineapples $4.45554 Tomatoes $3.45255 Onions $1 .45156 Bananas $3.4530 >

Run the following command, which will mark each line with an asterisk after the number of food is less than or equal to 20:

# awk'$4 20 {print $0;} 'food_list.txtNo Item_Name Price Quantity1 Mangoes $3.45 5 * 2 Apples $2.45 253 Pineapples $4.45 554 Tomatoes $3.45 255 Onions $1.45 15 * 6 Bananas $3.45 30

The above command actually runs as follows: 1. It uses an expression to check whether the fourth column (quantity ()) of each input line is less than or equal to, and if the condition is met, it will put an asterisk at the end. It checks whether the fourth column of each input line is greater than 20 with an expression of 4 > 20, and displays it if the condition is met.

But there is a problem. When the first expression is marked with the {printf "% s/t%s/n", 0, "* *";} command, the second expression is judged at the same step, which is a waste of time. So when we have printed the flag line with the first expression, we no longer need to print it again with the second expression 4 > 20.

To deal with this, we need to use the next command:

# awk'$4 20 {print $0;} 'food_list.txt

How to use awk's' next' command how to use awk's' next' command

When the input line uses the expression 4 4 > 20 {print $0;}, proceed to determine the next input line, instead of wasting time continuing to determine whether the current input line is still greater than 20.

The next command is very important when writing efficient command scripts, which can improve the speed of the script.

This is the end of the article on "how to use next commands in awk". Thank you for reading! I believe you all have a certain understanding of the knowledge of "how to use next commands in awk". If you want to learn more, you are welcome to follow the industry information channel.

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