/****
 * Example 1: A Traditional DynC Cooperatively Multithreaded Program
 ****/
main(void) {
    /* CoData structures for two named tasks */
    CoData t1, t2;

    while(1) {
        /* Keyboard handler */
        costate {
            while(1) {
                waitfor(kbhit());
                switch(getchar()) {
                    case '-':
                        /* Stop one of the currently running tasks */
                        if      (isCoRunning(&t1)) CoPause(&t1);
                        else if (isCoRunning(&t2)) CoPause(&t2);
                        else    printf("No tasks running.\n");
                        break;

                    case '+':
                        /* Start one of the currently stopped tasks */
                        if      (!isCoRunning(&t1)) CoResume(&t1);
                        else if (!isCoRunning(&t2)) CoResume(&t2);
                        else    printf("Both tasks running.\n");
                        break;
                }
            }
        }

        /* Task 1 (initially on) */
        costate t1 init_on {
            while (1) {
                /* Task 1 work goes here. */
                printf("Task 1\n");
                yield;
            }
        }

        /* Task 2 (initially off) */
        costate t2 {
            while (1) {
                /* Task 2 work goes here. */
                printf("Task 2\n");
                yield;
            }
        }
    }
}