如何利用C++ Builder获取系统的sid信息？

//---------------------------------------------------------------------------

#ifndef Unit1H
#define Unit1H
//---------------------------------------------------------------------------
#include <Classes.hpp>
#include <Controls.hpp>
#include <StdCtrls.hpp>
#include <Forms.hpp>
//---------------------------------------------------------------------------
class TForm1 : public TForm
{
__published:	// IDE-managed Components
TButton *Button1;
TEdit *Edit1;
TLabel *Label1;
void __fastcall Button1Click(TObject *Sender);
private:	// User declarations
public:		// User declarations
__fastcall TForm1(TComponent* Owner);
};
//---------------------------------------------------------------------------
extern PACKAGE TForm1 *Form1;
//---------------------------------------------------------------------------
#endif

//---------------------------------------------------------------------------

#include <vcl.h>
#pragma hdrstop

#include <stdio.h>
#include "Unit1.h"
#define MAX_NAME 256

//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
: TForm(Owner)
{
}
//---------------------------------------------------------------------------

void ConvertSid(PSID pSid, LPTSTR TextualSid)
{
PSID_IDENTIFIER_AUTHORITY psia = GetSidIdentifierAuthority(pSid);
DWORD sidLen = sprintf(TextualSid, TEXT("S-%lu-"), SID_REVISION);
sidLen += sprintf(TextualSid + strlen(TextualSid), TEXT("%lu"), psia->Value[5]);

int i = 0;
int subAuthorities = *GetSidSubAuthorityCount(pSid);
for (i = 0; i < subAuthorities; i++)
{
sidLen += sprintf(TextualSid + sidLen, TEXT("-%lu"), *GetSidSubAuthority(pSid, i));
}
}

void GetLocalSid(LPTSTR szSid)
{
char szUserName[MAX_NAME] = {0};
DWORD nameSize = sizeof(szUserName) ;
GetUserName(szUserName, &nameSize);

char szUserSid[MAX_NAME] = {0};
char szUserDomain[MAX_NAME] = {0};
DWORD sidSize = sizeof(szUserSid);
DWORD domainSize = sizeof(szUserDomain);
SID_NAME_USE snu;

LookupAccountName( NULL,
szUserName,
(PSID)szUserSid,
&sidSize,
szUserDomain,
&domainSize,
&snu
);

ConvertSid(szUserSid, szSid);
}

void __fastcall TForm1::Button1Click(TObject *Sender)
{
char szSid[MAX_NAME] = {0};
GetLocalSid(szSid);
Edit1->Text = szSid;
Edit1->SetFocus();
}
//---------------------------------------------------------------------------