Sample that kills the parent process. If you run from within a terminal, the program will terminate the calling shell (thus terminating the terminal window).

killppid.c

#include <signal.h>  /* For SIGKILL */

int main()
{
	/* Sends the SIGKILL signal to the Parent Process ID (ppid) */
	kill(getppid(), SIGKILL);

	return 0;
}