Remove blank lines from a file

grep -v "^$" file
To save the result, redirect the output to another file. grep -v "^$" file1 > file2

-1
By: hkyeakley
2009-02-19 18:11:58

These Might Interest You

  • Remove blank lines from files, even if some of the lines have whitespace (spaces, tabs, etc.). Also creates a .bak copy of the original file. Works on Mac also. Thanks to those all those who left comments. Show Sample Output


    0
    sed -i.bak '/^[[:space:]]*$/d' file_name
    Highwayman · 2009-04-07 11:32:06 4
  • Strips comments from at least bash and php scripts. Normal # and // as well as php block comments removes all of the: empty/blank lines lines beginning with # lines beginning with // lines beginning with /* lines beginning with a space and then * lines beginning with */ It also deletes the lines if there's whitespace before any of the above. Add an alias to use in .bashrc like this: alias stripcomments="sed -e '/^[[:blank:]]*#/d; s/[[:blank:]][[:blank:]]*#.*//' -e '/^$/d' -e '/^\/\/.*/d' -e '/^\/\*/d;/^ \* /d;/^ \*\//d'"


    -3
    sed -e '/^[[:blank:]]*#/d; s/[[:blank:]][[:blank:]]*#.*//' -e '/^$/d' -e '/^\/\/.*/d' -e '/^\/\*/d;/^ \* /d;/^ \*\//d' /a/file/with/comments
    unixmonkey6951 · 2009-11-10 17:47:22 2
  • This command will squeeze all consequent blank lines (including those with only space and tab charactes) to one. It will also empty the resulting line (remove the "|s/.*//" part if you don't need that).


    2
    :g/^\s*$/,/\S/-j|s/.*//
    clone · 2009-08-16 10:01:15 1
  • This will first remove any leading white space. If the line then starts with a comment character, it is cleared. If the result is an empty line, it's deleted. This allows for comment lines with leading white space.


    0
    sed 's/^[[:blank:]]*//; s/^#.*//; /^$/d' filename
    putnamhill · 2010-12-10 13:24:16 0

What Others Think

sed -i '/^$/d' file will make the change in place.
iqag · 486 weeks and 5 days ago
cat -s file1 > file2 remove repeated empty output lines (if you have 2 or more empty lines, 'cat' remove them, otherwise 'cat' don't).
n0ky75 · 486 weeks and 5 days ago
grep . $file
kst · 486 weeks and 5 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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