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Remove blank lines from a file using grep and save output to new file

Terminal - Remove blank lines from a file using grep and save output to new file
grep . filename > newfilename
2009-09-25 09:25:34
User: alvinx
Functions: grep
27
Remove blank lines from a file using grep and save output to new file

Alternatives

There are 2 alternatives - vote for the best!

Terminal - Alternatives
cat filename | grep .
2009-08-09 01:00:59
User: fraktil
Functions: cat grep
Tags: cat Linux grep
2

Pipe any output to "grep ." and blank lines will not be printed.

grep -v "^$" filename > newfilename
2009-09-24 12:21:43
User: eastwind
Functions: grep
1

The ^$ within the quotes is a regular expression: ^=beginning of line, $=end of line, with no characters between.

sed '/^$/d' file >newfile

Know a better way?

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What others think

This is superior: http://www.commandlinefu.com/commands/view/1864/remove-blank-lines-from-a-file

Comment by kenyon 150 weeks and 2 days ago

grep -v 'something to remoe' filename > filename

Somehow this erase all contents from the file, anyone know why?

Comment by leoman730 112 weeks ago

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