How can I insert a tab character with sed on OS X?

Question

I have tried:

echo -e \"egg\\t  \\t\\t salad\" | sed -E \'s/[[:blank:]]+/\\t/g\'

Which results in:

eggtsalad

Answer 1

A workaround for tab on osx is to use "\ ", an escape char followed by four spaces.

If you are trying to find the last instance of a pattern, say a " })};" and insert a file on a newline after that pattern, your sed command on osx would look like this:

sed -i '' -e $'/^\    \})};.*$/ r fileWithTextIWantToInsert' FileIWantToChange

The markup makes it unclear: the escape char must be followed by four spaces in order for sed to register a tab character on osx.

The same trick works if the pattern you want to find is preceded by two spaces, and I imagine it will work for finding a pattern preceded by any number of spaces as well.