Question

I have a file named file1 with following content:

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I would like to convert file1 into file2. Latter should look like this:

The answer to your question

A conclusive answer isn’t always possible.

When in doubt, ask people to cite their sources, or to explain

Even if we don’t agree with you, or tell you.

In case I simply execute cat file1 | tr -d "\n" > file2", all the newline characters will be deleted. Ho do delete only those newline characters, which are on the non-empty lines using the tr(1) utility?

Answer 1

perl -00 -lpe 'tr/\n//d'

-00 is Perl’s “paragraph” mode, reading the input with one or more blank lines as the delimiter. -l appends the system newline character to the print command, so it’s safe to delete all newlines in the input.