... Signals and pipes are two of them but Linux also supports the System V IPC mechanisms named after the Unix T M release in which they first appeared. ... A signal could be generated by a keyboard interrupt or an error condition such as the process attempting to access a non-existent location in its virtual memory. ... Linux also holds information about how each process handles every possible signal and this is held in an array of sigaction data structures pointed at by the task_struct for each...