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

The compound expression of awk can consist of the combination operator "&" for "and" and "|" for "OR".

The general way to write a compound expression is as follows:

(first expression) & (second expression)

Here, the entire expression is true only if both the first expression and the second expression are true.

(first expression) | | (second expression)

Here, as long as the first expression is true or the second expression is true, the whole expression is true.

Note: remember to add parentheses.

Expressions can be made up of comparison operators.

Now let's deepen our understanding with an example:

In this example, there is a text file tecmint_deals.txt that contains a random list of Tecmint transactions with name, price, and category.

TecMint Deal ListNo Name Price Type1 Mac_OS_X_Cleanup_Suite $9.99 Software2 Basics_Notebook $14.99 Lifestyle3 Tactical_Pen $25.99 Lifestyle4 Scapple $19.00 Unknown5 Nano_Tool_Pack $11.99 Unknown6 Ditto_Bluetooth_Altering_Device $33.00 Tech7 Nano_Prowler_Mini_Drone $36.99 Tech

We just want to print out items that cost more than $20 and whose type is "Tech" and mark them with (*) at the end of the line.

We are going to carry out the following orders.

# awk'($3 ~ / ^ / $[2-9] [0-9] * /. [0-9] [0-9] $/) & ($4 million = "Tech") {printf "% s/t%s/n", $0, "*";} 'tecmint_deals.txt6 Ditto_Bluetooth_Altering_Device $33.00 Tech * 7 Nano_Prowler_Mini_Drone $36.99 Tech *

In this example, we used two expressions in the compound expression:

Expression 1: (2-9 impulse. 0-9; find lines whose transaction price is more than 20, that is, the value is true only if the price satisfies 2-9 shock. 0-9 $/. Expression 2: (; find out if there is a kind of transaction, that is, the value is true only if 4 equals "Tech". Keep in mind that this line is marked (*) only if the states at both ends of the & & operator, that is, both expressions are true. This is the end of the article on "how to use awk compound expressions". Thank you for reading! I believe you all have a certain understanding of the knowledge of "how to use awk compound expressions". If you want to learn more, you are welcome to follow the industry information channel.

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