It's a bad idea to edit a file in-place without a backup, let's just put it that way. Creating a separate output file from your source means your source *is* the backup. So moritz's point, a little less succinctly put, is, "Don't edit a file with important data unless you can undo any changes."

(Or use version control.)

In reply to Re^3: Need a little help appending lines by macrobat
in thread Need a little help appending lines by perl4ever

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