code: public boolean remove(final Process process) {
      synchronized (processes) {
        boolean processRemoved = processes.removeElement(process);
        if (processRemoved && processes.size() == 0) {
          try {
            removeShutdownHook();
          } catch (IllegalStateException e) {
            /* if the JVM is shutting down, the hook cannot be removed */
            shutDownHookExecuted = true;
          }
        }
        return processRemoved;
      }
    }
docs: Returns <code>true</code> if the specified <code>Process</code> was
  successfully removed from the list of processes to destroy upon VM exit.
  
  @param process
  the process to remove
  @return <code>true</code> if the specified <code>Process</code> was
  successfully removed