The xml file gets generated with empty tags is like this <headertag></headertag>It's in consecutive lines and i usually use a perl script to find it based on new line character between tags as pattern (\n) but  Unix environment which I'm using now isn't supporting this perl script. Tried the same with sed but i couldn't find the place (line number) where there is a empty tag like this in a huge .xml file. Is there a solution to find this using sed or awk? 
Find empty tag in `xml` using Unix command
awk;sed;xml