void *thread_B(void *param)
{
random_sleep();
sem_wait(sem_BCD);
printf("B\n");
sem_post(sem_I);
random_sleep();
pthread_exit(NULL);
}
void *thread_F(void *param)
{
random_sleep();
sem_wait(sem_EF);
printf("F\n");
sem_post(sem_G);
random_sleep();
pthread_exit(NULL);
}
void *thread_I(void *param)
{
random_sleep();
sem_wait(sem_I);
sem_wait(sem_I);
sem_wait(sem_I);
printf("I\n");
random_sleep();
pthread_exit(NULL);
}
void spam_log(void *arg)
{
int i;
int tid = (*(int*)arg);
int lvl = ((*(int*)arg) % LOG_LVL_MAX) + 1;
for (i = 0; i < 10; i++) {
random_sleep();
}
for (i = 0; i < SPAM_LINES; i++) {
if (tid % 2) random_sleep();
LOG(lvl, "[%d/%d] SPAM LOG: %d", lvl, tid, i);
}
pthread_exit(NULL);
}
int main(int argc, char** argv)
{
pid_t child, returnPid, parentPid;
int i, status;
parentPid = getpid();
printf("main: parent Pid %d\n", parentPid);
for (i = 0; i < 3; i++) {
printf("fork child No. %d\n", i+1);
child = fork();
if (child == 0) {
random_sleep();
// beware of a fork bomb here, Google will know!
exit(EXIT_SUCCESS);
// exit(EXIT_FAILURE);
} else if (child == -1) {
perror("Problem while forking");
return 1;
} else {
printf("main: fork child No. %d with PID %d\n",
i+1, child);
}
}
while(1){
returnPid = wait(&status);
if (returnPid < 0 ) break;
printf("Child process ID as %d with status as %d\n",
returnPid, status);
}
printf("main: ******** ending here *********\n");
return 0;
}
int main(int argc, char **argv)
{
pthread_t tid[N_THREAD]; //tid array of A to I thread
int i; //iterator
//semaphore malloc
sem_BCD = (sem_t *) malloc(sizeof(sem_t));
sem_EF = (sem_t *) malloc(sizeof(sem_t));
sem_G = (sem_t *) malloc(sizeof(sem_t));
sem_I = (sem_t *) malloc(sizeof(sem_t));
//semaphore init
sem_init(sem_BCD, 0, 0);
sem_init(sem_EF, 0, 0);
sem_init(sem_G, 0, 0);
sem_init(sem_I, 0, 0);
while(1)
{
printf("\n\nNEW LOOP\n");
//thread creation
i = 0;
pthread_create(&tid[i++], NULL, thread_A, NULL);
pthread_create(&tid[i++], NULL, thread_B, NULL);
pthread_create(&tid[i++], NULL, thread_C, NULL);
pthread_create(&tid[i++], NULL, thread_DH, NULL);
pthread_create(&tid[i++], NULL, thread_E, NULL);
pthread_create(&tid[i++], NULL, thread_F, NULL);
pthread_create(&tid[i++], NULL, thread_G, NULL);
pthread_create(&tid[i++], NULL, thread_I, NULL);
random_sleep();
//wait thread destruction
for(i=0; i<N_THREAD; i++)
{
pthread_join(tid[i], NULL);
}
random_sleep();
}
return 0;
}
