grep will find a specific string of text in a file, but awk gives you the ability to isolate a particular column of text.

For example, we have a text file with the following content in a file called test.txt:

This is a line of text demonstrating the use of awk.

So, running the following command: cat test.txt |awk -F " " '{print $2}' - will yield the following output.

is

So what have we done here? We have piped the file test.txt into awk, and by using the -F parameter, have set " " (space) as the delimiter to use.
And '{print $2}' tells awk to print the text after the second space in the row.

We could for example have another file, using the "-" instead of space as a delimiter.

This-is-a-line-of-text-demonstrating-the-use-of-awk.

Running the command: cat test.txt |awk -F "-" '{print $4}' will print the following text string:

line

So this time we specified "-" as the delimiter.

Try this for yourself with differing strings in the text file, and different delimiters.

You can also mix delimiters.




Tags: AWK , Linux

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