I have a file1, that has a few lines (tens), and a much longer file2 (~500,000 lines). The lines in each file are not identical, although there is a subset of fields that are identical. I want to take fields 3-5 from each line in file1, and search file2 for the same pattern (just those three fields, in same order -- in file2, they fall in fields 2-4). If any match is found, then I want to delete the corresponding line from file1. I have a file1, that has a few lines (tens), an