I have a java application that got
sigaction() and pass to it a
struct sigaction which has the desired signal handler in
sa_sigaction and the
SA_SIGINFO flag in
sa_flags set. With this flag, your signal handler will receive three arguments, one of which is a
siginfo_t structure containing the sender's PID and UID.
signalfd() and read
signalfd_siginfo structures from it (usually in some kind of a select/poll loop). The contents will be similar to
Which one to use depends on how your application is written; they probably won't work well outside plain C, and I wouldn't have any hope of getting them work in Java. They are also unportable outside Linux. They also likely are the Very Wrong Way of doing what you are trying to achieve.