The problem I was having was failure to use a compiler option that would allow the compiled program to deal with the CtrlC event. Now that I've got a better understanding of this in C and assembler, I can move on to passing messages between programs. This is interesting to me because I have some useful C source that I would like to have compiled and called from my own assembly program, instead, I'm going to try getting the output I want from the C program via message passing.