You might want to try this one-liner: 
$ echo 'foo
> bar
> foobar
> baz
> foobar'  | perl -ne 'print unless /^bar/;'
foo
foobar
baz
foobar

[download]
The output might be redirected to a file if needed.

In reply to Re: How to remove a whole line if matches a keyword in a file. by Laurent_R
in thread How to remove a whole line if matches a keyword in a file. by Rahul2772

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