As far back as 1974, the RISOS (Research in Secure Operating Systems) project at Lawrence Livermore Laboratory Artificial Intelligence and Security: An Overview 75 had developed a set of tools to analyze operating systems for security flaws. The tools used powerful pattern-matching techniques to search the code for sequences of operations that might characterize security flaws. The tools analyzed various assembly languages, and are not currently in use; although at the time good results were obtained. The tools should be updated to analyze high-level languages.