Linux C programming with signal & process

Question

I want ask How can I get pid and uid of sending process?????

I want make program which use signal.

I made sig_handler which print uid of sending process, pid of sending process.

And by using SIGCHLD I want print uid and pid of sending process.

How can I do that?

Answer 1

Your question is similar to others here: see How can I tell in Linux which process sent my process a signal (and probably others) for Linux-specific details.

If your problem is really about ways processes on Linux can communicate with each other - that is, general interprocess communication (IPC) - there are also lots of resources here on Stackoverflow and elsewhere: Which Linux IPC technique to use? , among others.