c++ CreateProcess调用dos命令

// test.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h"
#include <windows.h>

#include <iostream>
#include <fstream>
#include <string>

using namespace std;

int _tmain(int argc, _TCHAR* argv[])
{
    TCHAR szPath[MAX_PATH];
    GetSystemDirectory(szPath, sizeof(szPath));

    wstring str = szPath;
    str.append(L"\\cmd.exe");  

    wstring cmdStr= L"systeminfo";

    STARTUPINFO si;
    ZeroMemory(&si, sizeof(si));

    si.cb = sizeof(si);
    si.wShowWindow = SW_HIDE;

    PROCESS_INFORMATION pi;
    ZeroMemory(&pi, sizeof(pi));

    TCHAR temp[] = L"/c systeminfo";

    BOOL bRet = CreateProcess(str.c_str(), temp, NULL, NULL, FALSE, CREATE_NO_WINDOW, NULL, NULL, &si, &pi);//
    if (bRet)
    {
        WaitForSingleObject(pi.hProcess, );// 等待程序退出
        CloseHandle(pi.hProcess);
        CloseHandle(pi.hThread);
    }

    system( "PAUSE ");
}