how to get the blank line number of a file?

Shell Programming and Scripting
1

I want to get the blank line number of a file.
example:
9000|9000|WW|1|1|SL|472|472|LC|2272|1072|MTY|niceDay

9000|9000|WW|1|1|SL|470|470|MC|1270|1172|MPVT|nice

9000|9000|WW|1|1|SL|472|472|LC|1072|1672|MBD|Sonice

9000|9000|WW|1|1|SL|473|473|LF|1173|1173|MTY|nice666

I want to get the result like this:
2
4
6

Thanks!

2

if you have Python

#!/usr/bin/env python
for n,line in enumerate(open("file")):
    if line.strip()=="": print n+1

output

# ./test.py
2
4
6

with awk

# awk '/^$/{print NR}' file
2
4
6
3

this will do

awk '/^$/{print NR}' filename
4

The same thing with sed :

sed -n '/^$/=' filename

Jean-Pierre.

5

It works.
Thank you so much!

6

And then some more:

perl -ne '{print $.,"\n" if /^$/}' <file>

tyler_durden