WSAStartup函数如何启动使用Winsock DLL？

根据文件

The WSAStartup function must be the
first Windows Sockets function called
by an application or DLL. It allows an
application or DLL to specify the
version of Windows Sockets required
and retrieve details of the specific
Windows Sockets implementation. The
application or DLL can only issue
further Windows Sockets functions
after successfully calling WSAStartup.

此函数初始化WSADATA数据结构,但在套接字编程中,我们不会将WSDATA传递给任何函数,所以该程序如何知道Windows Sockets版本和其他详细信息？

例如在这段代码中

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

void Run(int argc,char* argv[])
{
    char* host = argc < 2 ? "" : argv[1];
    struct hostent* entry = gethostbyname(host);

    if(entry)
    {
        struct in_addr* addr = (struct in_addr*) entry->h_addr;
        printf("IP Address: %sn",inet_ntoa(*addr));
    }
    else
        printf("ERROR: Resolution failure.n");
}

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

    if(WSAStartup(0x202,&wsaData) == 0)
    {
        Run(argc,argv);
        WSACleanup();
    }
    else
        printf("ERROR: Initialization failure.n");
}

在这个例子中,我正在使用WSAStartup()函数初始化WSADATA数据结构,之后我不会在任何地方传递wsaData.

那么我的程序如何知道wsaData的细节呢？

谢谢.