Wincap获取设备

// hello.cpp : 定义控制台应用程序的入口点。
//
#define  WPCAP
#define HAVE_REMOTE
#include "stdafx.h"
#include <iostream>
#include <algorithm>
#include <string>
#include <vector>
/*
* we do not want the warnings about the old deprecated and unsecure CRT functions
* since these examples can be compiled under *nix as well
*/

#include "pcap.h"

void  main()

{

	pcap_if_t *alldevs,*d;

	int i=0;

	char errbuf[PCAP_ERRBUF_SIZE];

	/* PCAP_ERRBUF_SIZE =256，在pcap.h中定义*/            
	if (pcap_findalldevs(&alldevs, errbuf) == -1) /* 这个API用来获得网卡的列表*/

	{	
		fprintf(stderr,"Error in pcap_findalldevs: %s\n", errbuf);

		//errbuf参数当有异常情况发生时这个参数会被填充为某个特定的错误字串

		return;

	} 
	/* 显示列表的响应字段的内容*/

	for(d=alldevs;d;d=d->next)
	{ 
		printf("%d. %s", ++i, d->name);

		if (d->description)  printf(" (%s)\n", d->description);

		else  printf(" (No description available)\n");

	}



	if(i==0)

	{
		printf("\nNo interfaces found! Make sure WinPcap is installed.\n");

		return;

	}



	/*We don't need any more the device list. Free it */

	pcap_freealldevs(alldevs); //释放掉内存资源

}