But it can implement a signal handler function to override this behaviour. Used by OS kernel to tell the process about an exception (like division by 0). Command line kill command is another example of using signals. The signal namespace is just one integer, so collisions are very possible. Not recommended to use signals for IPC.
that can be read and written by other processes. Advantages: * data is never copied * any process with appropriate permission can read and write Disadvantage: * fragile—if it is corrupted, all processes are corrupted Access it from one process, use more conventional IPC.