获取主机名称和ip，用户名

#include <iostream>
#include <string>
#include <winsock2.h>
#pragma comment(lib,"ws2_32.lib")

using namespace std;

int main(int argc, char* argv[])
{

string ip_list;
char PCnameBuffer[128];    //获得本地计算机名
WSAData data;              //初始化:如果不初始化，以下代码将无法执行
if(WSAStartup(MAKEWORD(1,1),&data)!=0)
{
cout<<"初始化错误,无法获取主机信息..."<<endl;
}
else
{
if(0==gethostname(PCnameBuffer,128))
{
struct hostent* pHost;  //获得本地IP地址
pHost=gethostbyname(PCnameBuffer);  //pHost返回的是指向主机的列表
for (int i=0;pHost!=NULL&&pHost->h_addr_list[i]!=NULL;i++)
{
string tem = inet_ntoa(*(struct in_addr *)pHost->h_addr_list[i]);
ip_list += tem;
ip_list += "\n";
}
}
else
{
cout<<"获取主机信息失败..."<<endl ;
}
}
cout<<PCnameBuffer<<endl;
cout<<ip_list<<endl;
getchar();
return 0;
}

获取用户名：

#include <iostream>
#include <afx.h>
#pragma comment(lib,"Advapi32.lib")
using namespace std;

int main()
{
CString strUserName;

LPTSTR szBuffer=new wchar_t[300];
DWORD dwSize=300;
GetUserName(szBuffer,&dwSize);
strUserName=szBuffer;
delete szBuffer;
const size_t newsizew = (strUserName.GetLength() + 1)*2; //
char *ch = new char[newsizew];
WideCharToMultiByte(CP_OEMCP,NULL,strUserName,-1,ch,newsizew,0,NULL);// m_cstr --> ch
cout<<ch<<endl;
return 0;
}