If you have a text file that contains a lot a lot of blank lines, you may want to avoid them printing in the screen when you try to read that file, there is a simple way to do that using either
I have create a file to show you how this works.
cat -n text-file.txt
This is the output with all the blank lines
1 Hello 2 3 This is a text file 4 with 5 6 a lot 7 8 9 10 11 of blank lines 12 13 14 that I will use to 15 16 17 18 19 show the uses of -s switch 20 21 of the 22 23 24 25 26 less command 27
I have used
-n to print the line numbers as you can see there are 27 lines there but a lot of them are contiguous blank lines, now lets see the output with the
-s swith on.
cat -s -n text-file.txt
1 Hello 2 3 This is a text file 4 with 5 6 a lot 7 8 of blank lines 9 10 that I will use to 11 12 show the uses of -s switch 13 14 of the 15 16 less command 17
Now there are only 17 lines printed, the file has not changed only the output of cat on the screen, contiguous blank lines were converted into only one blank line.
You can also create a new file, redirecting the output to another file
cat -s text-file.txt > new-text-file.txt
-s switch also works on