int shmid;
/**
- * Message shared by processes. Contains array of process IDs
+ * Structure holding array of process IDs.
+ * Message is shared by processes. Contains array of process IDs
*/
struct message {
pid_t pids[3];
struct message * processes = NULL;
/**
- * Message queue variables
+ * Message Queue variables
+ */
+
+/**
+ * Unique key of message queue.
*/
key_t qkey = 12356;
+
+/**
+ * Queue descriptor.
+ */
int qid;
+/**
+ * Structure holding queue message data.
+ * Parameter mtype describes process to whom message is sent.
+ * Parameter signo is a signal to raise after getting message.
+ */
struct queue_message {
long mtype;
int signo[1];
}
else if (signo == SIGTSTP) {
fprintf(stderr, "[%s] > Signalling other processes..\n", "process3");
+ processes->pids[2] = 0;
notify_other_processes(signo);
+// sleep(1);
+ processes->pids[2] = getpid();
fprintf(stderr, "[%s] > Closing pipe\n", "process3");
close(read_descriptor);
}
else if (signo == SIGCONT) {
fprintf(stderr, "[%s] > Signalling other processes..\n", "process3");
+ processes->pids[2] = 0;
notify_other_processes(signo);
+// sleep(1);
+ processes->pids[2] = getpid();
fprintf(stderr, "[%s] > Opening pipe\n", "process3");
read_descriptor = open(read_pipe, O_RDONLY);