awk - How to add N blank lines between all rows of a text file?

Awk - How to add N blank lines between all rows of a text file?

To add N blank lines between all rows of a text file using awk, you can achieve this by manipulating the output with printf to insert blank lines after printing each line of the input file. Here's how you can do it:

Example Scenario

Let's say you have a file data.txt with the following content:

Line 1 Line 2 Line 3

Adding N Blank Lines

Suppose you want to add 2 blank lines between each existing line in data.txt.

You can use awk to achieve this:

awk -v N=2 '{print $0; for (i=1; i<=N; i++) print ""}' data.txt
  • Explanation:
    • -v N=2: Defines a variable N with the number of blank lines you want to add (in this case, 2).
    • '{print $0; for (i=1; i<=N; i++) print ""}':
      • print $0: Prints each line from the input file ($0 represents the entire line).
      • for (i=1; i<=N; i++) print "": Prints N blank lines ("" represents an empty line) after each line.

Output

Running the above awk command on data.txt will produce the following output:

Line 1 Line 2 Line 3

Adjusting the Number of Blank Lines

To adjust the number of blank lines (N), simply change the value of -v N=2 to the desired number.

Saving Changes to the File

If you want to save the modified content back to data.txt, you can redirect the output to a temporary file and then replace the original file:

awk -v N=2 '{print $0; for (i=1; i<=N; i++) print ""}' data.txt > tmp && mv tmp data.txt

This command creates a temporary file (tmp), writes the modified content to it, and then replaces the original file (data.txt) with tmp.

Notes

  • Ensure you adjust N to the number of blank lines you want to add.
  • This approach efficiently inserts blank lines using awk without needing external tools or complex scripting, making it suitable for various text manipulation tasks in shell scripting.

Examples

  1. How to add 2 blank lines between each row using awk? Description: Insert two blank lines between every line of a text file using awk.

    awk '1; { for (i=0; i<2; i++) print "" }' input.txt

  2. Inserting multiple blank lines between rows in a text file using awk? Description: Add a customizable number of blank lines (N) between each row in a text file.

    awk -v N=3 '1; { for (i=0; i<N; i++) print "" }' input.txt

  3. How to append 4 blank lines between all lines of a file using awk? Description: Append four blank lines after each line in a text file using awk.

    awk '{ print $0 "\n\n\n\n" }' input.txt

  4. Using awk to insert 5 empty lines between rows in a file? Description: Use awk to insert five empty lines between each line of a text file.

    awk '{ print $0 "\n\n\n\n\n" }' input.txt

  5. Add blank lines every 3 lines in a file using awk? Description: Insert blank lines after every three lines in a text file using awk.

    awk 'NR % 3 == 0 { print "" } 1' input.txt

  6. How to add 1 blank line between each row of a file using awk? Description: Insert one blank line between every line of a text file using awk.

    awk '1; { print "" }' input.txt

  7. Inserting 6 blank lines between all lines of a file using awk? Description: Insert six blank lines after each line in a text file using awk.

    awk '{ print $0 "\n\n\n\n\n\n" }' input.txt

  8. Using awk to add 2 empty lines after every 4 lines in a file? Description: Use awk to add two empty lines after every fourth line in a text file.

    awk 'NR % 4 == 0 { print $0 "\n\n" } NR % 4 != 0 { print $0 }' input.txt

  9. How to add 3 blank lines after each line of a file using awk? Description: Append three blank lines after each line in a text file using awk.

    awk '{ print $0 "\n\n\n" }' input.txt

  10. Adding a variable number of blank lines between rows in a text file using awk? Description: Use a variable to define the number of blank lines (N) to insert between each row in a text file using awk.

    awk -v N=4 '1; { for (i=0; i<N; i++) print "" }' input.txt

More Tags

thread-synchronization python-2.6 hana merge orders floating-action-button static file-put-contents xunit.net django-admin-actions

More Programming Questions

More Biochemistry Calculators

More Biology Calculators

More Math Calculators

More General chemistry Calculators