You can also binary search with "look -b". The version included with Debian Unstable doesn't support large files, but it will search multiple files at once, so

You can also binary search with "look -b". The version included with Debian Unstable doesn't support large files, but it will search multiple files at once, so you can split without breaking lines, eg. with "split -C 1999m", and search with "look -b SHASUM splitfile*".