ack is a grep-like source code search tool. The latest version of ack is v3.8.1, released 2024-12-31. Changelog for v3.8.1 Designed for programmers with large heterogeneous trees of source code, ack is written in portable Perl 5 and takes advantage of the power of Perl's regular expressions. What's new in ack? New boolean options --and, --or and --not The new repeatable --and, --or and --not optio