Count number of blank lines in a file

unix sed grep text-files
Sudar picture Sudar · Nov 22, 2012 · Viewed 76k times · Source

In count (non-blank) lines-of-code in bash they explain how to count the number of non-empty lines.

But is there a way to count the number of blank lines in a file? By blank line I also mean lines that have spaces in them.

Answer

kev picture kev · Nov 22, 2012

Another way is:

grep -cvP '\S' file
  • -P '\S'(perl regex) will match any line contains non-space
  • -v select non-matching lines
  • -c print a count of matching lines

If your grep doesn't support -P option, please use -E '[^[:space:]]'

Related questions

How to remove leading whitespace from each line in a file

I have a file that looks something like this: for (i = 0; i < 100; i++) for (i = 0; i < 100; i++) for (i = 0; i < 100; i++) for (i = 0; i < 100; i++) for (i = 0; i < 100; i++) for (i = 0; i < 100; i++) for (…

Read More
Print lines in one file matching patterns in another file

I have a file with more than 40.000 lines (file1) and I want to extract the lines matching patterns in file2 (about 6000 lines). I use grep like this, but it is very slow: grep -f file2 file1 > out Is there …

Read More
Find and replace in file and overwrite file doesn't work, it empties the file

I would like to run a find and replace on an HTML file through the command line. My command looks something like this: sed -e s/STRING_TO_REPLACE/STRING_TO_REPLACE_IT/g index.html > index.html When …

Read More