vc生成dll

#include "stdafx.h"
#include <process.h>
BOOL APIENTRY DllMain( HANDLE hModule,
                       DWORD  ul_reason_for_call,
                       LPVOID lpReserved
      )
{
    return TRUE;
}

extern "C" void __declspec(dllexport)rundos(char cmd[])
{
 system(cmd);
}