Structure marking is a programming technique that defends data against damage, especially from software bugs. It adds flags to data structures and checks them at each use to detect damaged data immediately.
Tom Van Vleck has learned from wonderful colleagues in the computer field since 1959, when he was a high school student building computers in a suburban basement. He worked on the Multics operating system for sixteen years, and then spent twenty years at Silicon Valley startups, working on operating systems, applications, software tools and quality, and security. Currently he is doing computer security research at Network Associates Laboratories.