输出进程相关联的环境变量信息（使用GetEnvironmentStrings取得信息，然后使用StringCchCopyN和StringCchPrintf保证字符串不会越界）

void DumpEnvironmentStrings()
{
#define MAX_ENVIRONMENT_NAME_LENGTH     (128)
#define MAX_ENVIRONMENT_VALUE_LENGTH    (1024)
    LPTSTR lpszEnvString = GetEnvironmentStrings();
    if(NULL == lpszEnvString)
    {
        return ;
    }

    TCHAR* pEnvBlock = lpszEnvString;
    const TCHAR szToken = _T('=');
    TCHAR szName[MAX_ENVIRONMENT_NAME_LENGTH] = {0};
    TCHAR szValue[MAX_ENVIRONMENT_VALUE_LENGTH] = {0};
    while('\0' != *pEnvBlock)
    {
        if(szToken == *pEnvBlock)
        {
            pEnvBlock += _tcslen(pEnvBlock) + 1;
            continue;
        }
        TCHAR* pToken = _tcschr(pEnvBlock, szToken);
        if(NULL == pToken)
        {
            break;
        }
        memset(szName, 0, sizeof(szName));
        memset(szValue, 0, sizeof(szValue));
        StringCchCopyN(szName, _countof(szName), pEnvBlock, pToken - pEnvBlock);
        StringCchPrintf(szValue, _countof(szValue), _T("%s"), pToken + 1);
        _tprintf(_T("%s : %s\r\n\r\n"), szName, szValue);
        pEnvBlock += _tcslen(pEnvBlock) + 1;
    }
    FreeEnvironmentStrings(lpszEnvString);
    lpszEnvString = NULL;
}

// 测试代码
#include "stdafx.h"
#include <Windows.h>
#include <strsafe.h>

int _tmain(int argc, _TCHAR* argv[])
{
    DumpEnvironmentStrings();
    return 0;
}

 

 http://blog.csdn.net/visualeleven/article/details/8122081