The agrep tool is similar to the commonly used grep utility, but agrep
can be used to search for approximate matches.
The agrep tool searches text input for lines (or records separated by
strings matching arbitrary regexps) that contain an approximate, or
fuzzy, match to a specified regexp, and prints the matching lines.
Limits can be set on how many errors of each kind are allowed, or
only the best matching lines can be output.
Unlike other agrep implementations, TRE agrep allows full POSIX
regexps of any length, any number of errors, and non-uniform costs.