Wordwrap long text string using "\n"

fold -sw 20 <(echo "Long Text to be wrapped with \"\n\"") |sed ':a;N;$!ba;s/ *\n/\\n/g'
I used this fragment with Imagemagick convert so that I can place long text strings in pictures. The "\n" gets converted to a true newline in the image. So this fragment uses fold command to wrap the line and then sed to convert newlines (and any trailing spaces on the line) to the text "\n"
Sample Output
Long Text to be\nwrapped with "\n"

1
2015-04-16 21:06:53

What Others Think

That's nice bit of sed. Would you like to explain how it works?
flatcap · 179 weeks and 3 days ago
So 1st off I just copied it from the net so I can't take credit. How does it work? 1) It's four sed command ":a", "N" "$!ba" and 's/ *\n"/\\n/g' ":a" defines a label for a later jump command "N" Read all the next line to the pattern space. Exit loop if no more text "$!ba" Branch to label if NOT at end of file "s/ *\n"/\\n/g" Find all instance of a real newline char, optionally proceeded by one or more spaces, and replace with the literal "\" followed by an "n". Do it for all occurrences in the pattern space It could be done more simply with tr, but that does not handle the spaces preceding the newline char
alecthegeek · 179 weeks and 3 days ago
Thanks for the explanation. > It could be done more simply with tr That's the first thing that I thought, but it doesn't work. tr does a one-to-one character replacement. ... | tr '\n' '\\n' replaces newlines with backslash only.
flatcap · 179 weeks and 3 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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