removing blank lines in a text file
 

how do I delete all blank lines in a text file? thanks :)

There are a thousand ways to do that. If you want to do it from the ci:
Or, if you prefer vi/vim:

Look at table C-2 --> http://tldp.org/LDP/abs/html/abs-guide.html#AEN20423

Used this in the past to strip blank lines and comments

Why couldn't you just use: sed /^$/d < oldfile > newfile

I prefer grep:
#print only lines that contain non-whitespace characters
grep '[^[:space:]]' oldfile > newfile

you can skin the cat
and if your sed supports -i option

or vi the file and in command mode do this:

That will only eliminate spaces, and it will do so in sentences too. You would still have blank lines and tabsbutyourwordswouldallruntogether.

If you want to modify the original file (instead of creating a second, modified one), you can use the -i option. This version also deletes lines with spaces and tabs on... maybe you want to keep them, I don't know:

Sorry, I miss understood the question, the correct syntax is this (in vi command mode):

-custangro

That's the ticket. You could also use \s in that to get lines that have non-printing chars: