live data

live data n.  1. Data that is written to be interpreted and
   takes over program flow when triggered by some un-obvious
   operation, such as viewing it.  One use of such hacks is to break
   security.  For example, some smart terminals have commands that
   allow one to download strings to program keys; this can be used to
   write live data that, when listed to the terminal, infects it with
   a security-breaking {virus} that is triggered the next time a
   hapless user strikes that key.  For another, there are some
   well-known bugs in {vi} that allow certain texts to send
   arbitrary commands back to the machine when they are simply viewed.
   2. In C code, data that includes pointers to function {hook}s
   (executable code).  3. An object, such as a {trampoline}, that
   is constructed on the fly by a program and intended to be executed
   as code.