jba@harald.ruc.dk (Jan B. Andersen) (10/16/89)
cassel@sce.carleton.ca (Ron Casselman) writes: >The program would copy itself to a different >part of memory and change all address references as it did so. It would >then load a second program into the original location. (all programs >under CP/M started at a fixed location). The second program would then >begin to run. Sorry I cannot remember any more details as to the purpose >of this self-modifying code. Sounds like the CP/M debugger to me (name ??). I believe that self-modifying code is quite common in small single-processes OS's, but except for very special cases (like I/O drivers which someone has mentioned) I think it should be avoided at all cost.