METHOD AND APPARATUS FOR PROGRAM UPDATING

A computer system is disclosed in which individual executing process can be replaced with updated or corrected versions of themselves without interrupting or otherwise interfering with the operation of the computer system. In particular, embedded in the process itself is a command or function or subroutine call which operates to overlay the process code in memory with an updated version of itself, without losing or altering the relationships of the process to the other processes in the computer. As an example, in a UNIX system, the execute command can be used to perform the replication function. The replication process can be triggered by an inter-process signal, by the occurrance of an external condition, or by a triggering signal embedded in the normal data input to the process.