Removing blank lines

Vi ---> Removing blank lines

Blank lines can be removed from a file with any of the following:

    :v/./d

or

    :g/^$/d

or

    :%!cat -s

If you want to get rid of duplicate blank lines, but leave the first blank line intact, try:

    :%!sed /./,/^$/!d

Be aware that you may need to get rid of trailing whitespace first. This can be accomplished with

    :%s/[ ^I]*$/