title: Accessing key_t generated by IPC_PRIVATE
body: <p>I'm trying to synchronize and make a few threads/processes communicate for a project and I'd ideally like to access some shared memory blocks between them, without having them clash with other processes/resources.</p>
  <p>I know IPC_PRIVATE will generate a unique key when calling <code>shmget()</code> to create it, but if I then need that key to open that region somewhere in other processes, how can I access that generated <code>key_t</code> value so that I can send it to the other process?</p>
  <p>I'm currenty sending data through IPC message-queues, and so I can send the shmid value, but as far as I know that doesn't work since the shmid value is unique for each process.</p>
  <p>Do I have no other options but try luck with <code>ftok()</code> and some random files? Do I have to choose a different file for each block of different shared memory I wish to create?</p>
  <p>Thank you for your time.</p>