But you can't just substitute arbitrary text in a text file, unless it happens to have exactly the same length. As file_b is being read and searched, each line should be copied out to a new file, and updated line printed in it's proper order, and the remainder of file_b copied. Then rename the new file to file_b (making sure file_b is closed).

In reply to Re^2: Searching and replacing text by ysth
in thread Searching and replacing text by Anonymous Monk

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