I want to insert into file "B" (...) missing line above matching second line

Could you clarify that?

It's not at all clear (to me?) what want to do here:

  1. Is it the first or second of each pair that must be inserted into the second file?
  2. Where do you want the new values added to the second file?

    At the end? At some specific position?

  3. How do you decide which values need adding?
  4. Pls note lines may appear many times.

    Which lines appear many times in which file?

As you can see, your description left me very confused. Often in these cases the best expaination is a simple example?

Examine what is said, not who speaks.
Silence betokens consent.
Love the truth but pardon error.

In reply to Re: Insert row from file by BrowserUk
in thread Insert row from file by smbs

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