How can I cause a child process to exit when the parent does?

Question

I am launching a child process with ProcessBuilder, and need the child process to exit if the parent process does. Under normal circumstances, my code is stopping the child

Answer 1

Try to send a kill signal to the child process from the parent when the parent stops

Answer 2

For windows, I came up with this polling hack:

static int getPpid(int pid) throws IOException {
    Process p = Runtime.getRuntime().exec("C:\\Windows\\System32\\wbem\\WMIC.exe process where (processid="+pid+") get parentprocessid");
    BufferedReader br = new BufferedReader(new InputStreamReader(p.getInputStream()));
    br.readLine();
    br.readLine();
    String ppid= br.readLine().replaceAll(" ","");
    return Integer.parseInt(ppid);
}
static boolean shouldExit() {
    try {
        String pid = ManagementFactory.getRuntimeMXBean().getName().split("@")[0];
        int ppid = getPpid(Integer.parseInt(pid));
        /* pppid */ getPpid(ppid);
    } catch (Exception e) {
        return true;
    } 
    return false;
}

Answer 3

For a single child processes you can manage this by inverting the child/parent relationship. See my answer to a later incarnation of this question.