Compiling a HeNCE program is very easy. Simply pick ``Build'' from the PVM Console Build menu. Your program and subroutines will automatically be compiled on all necessary machine types as defined by the current cost matrix. If there are errors, messages will appear in the Information segment of the htool window or perhaps in the center of the PVM Console segment.
If you change either your HeNCE program, a sequential subroutine, or the current cost matrix, you should rebuild before attempting to run your program again.
Running programs once they are compiled, is equally easy. Pick ``Run Program'' from the PVM Console Run menu. As the program runs, its progress will be animated. The icons that make up the HeNCE graph will change to show the node's state. Figure 8 defines the meening of the changed icons.
The state of abstract parallel machine is displayed in the lower right of the htool window during the program run. There is a strip for each host. The meaning of the strips is color coded as shown in Table 2.
Output the program writes to the UNIX standard output (stdout) will appear in the scrolling region of the PVM Console window segment.
Once your program begins running, it will remain in run mode until you pick ``Exit Run Mode'' from the PVM Console Run menu. Until you do this, you will not be able to edit your HeNCE graph, etc.
Trace information is written, by default, to a file called ``hence.trace.'' This can be changed by picking ``Set Trace File'' from the PVM Console Run menu. Trace data is always saved. As is described below, it can be used to replay the program's animation.
In order to run your program, the necessary PVM demons must also be running. If they are not, HeNCE starts them for you automatically. Before exiting htool, you will probably want to halt them by picking ``Halt PVM'' from the PVM Console PVM menu. If you do not, you will likely leave unwanted processes running on all of the hosts in you cost matrix as well as the host that is running htool.
It is quite possible that your HeNCE program will not run to completion due to bugs. For example, one of your sequential subroutines might contain a bug that causes a divide by zero or a segmentation violation. If this occurs you may want to pick ``Kill Program'' from the PVM Console Run menu followed by ``Exit Run Mode.''