@Test(timeout = 30000)
public void testDestroyProcessTree() throws IOException {

  // test process
  String pid = "100";
  // create the fake procfs root directory.
  File procfsRootDir = new File(TEST_ROOT_DIR, "proc");
  try {
    setupProcfsRootDir(procfsRootDir);
    // crank up the process tree class.
    createProcessTree(pid, procfsRootDir.getAbsolutePath());
    // Let us not create stat file for pid 100.
    Assert.assertTrue(ProcfsBasedProcessTree.checkPidPgrpidForMatch(pid,
      procfsRootDir.getAbsolutePath()));
  } finally {
    FileUtil.fullyDelete(procfsRootDir);
  }
}