Question

How to let the Runtime.getRuntime().exec(p) run without waiting for the sleep 10??
Currently its wrong, its waiting until the exec gets complete and then moves to next. Where i need to on the fly let the exec running so that after 10 second later it can kill the PresentationInProjector.jpg.

Example:

   Runtime.getRuntime().exec("(sleep 10; echo '09|00|CC|01|83|88' | nc localhost 58888) &");
   PlayThisSlideShow("PresentationInProjector.jpg");

Answer 1

According to the docs exec():

Executes the specified string command in a separate process.

So any call to exec() should not block unless you used waitFor() on the returned process of the Runtime .

Here is a small example(Exception handling omitted):

Process p=Runtime.getRuntime().exec("cmd.exe /c ping 127.0.0.1 -n 10");

System.out.println("Here 1");//this will execute immediately

try {

    p.waitFor();

    System.out.println("Here 2");//this will only be seen after +- 10 seconds and process has finished

} catch (InterruptedException ex) {
   ex.printStackTrace(); 
}