On-the-fly program modification: systems for dynamic updating

Several dynamic software-based updating systems that are in the research and production stages are described. In particular, the procedure-oriented dynamic updating system (PODUS) is discussed. In PODUS, a program is updated by loading the new version of the program and replacing each old procedure with its corresponding new procedure during execution. Updating a procedure involves changing the binding from its current version to the new version. When all procedures have been replaced by their corresponding new versions, the program update is completed.<>