关于 error LNK2019 无法解析的外部符号

[xiaochangcong123]

首先，我在网上找到了很多关于这类型错误的博客什么之类的。我也看了一下，但是问题还未解决。
源代码如下：

#ifdef _MSC_VER
//*
// * we do not want the warnings about the old deprecated and unsecure CRT functions
// * since these examples can be compiled under *nix as well
// */
#define _CRT_SECURE_NO_WARNINGS
#endif

#include "pcap.h"

#ifndef WIN32
	#include <sys/socket.h>
	#include <netinet/in.h>
#else
	#include <winsock.h>
#endif

// Function prototypes
void ifprint(pcap_if_t *d);
char *iptos(u_long in);
char* ip6tos(struct sockaddr *sockaddr, char *address, int addrlen);

int main()
{
	pcap_if_t *alldevs;
	pcap_if_t *d;
	char errbuf[PCAP_ERRBUF_SIZE+1];

	/* Retrieve the device list */
	if(pcap_findalldevs(&alldevs, errbuf) == -1)
	{
		fprintf(stderr,"Error in pcap_findalldevs: %s\n", errbuf);
		exit(1);
	}

	/* Scan the list printing every entry */
	for(d=alldevs;d;d=d->next)
	{
		ifprint(d);
	}

	/* Free the device list */
	pcap_freealldevs(alldevs);

	return 1;
}

/* Print all the available information on the given interface */
void ifprint(pcap_if_t *d)
{
  pcap_addr_t *a;
  char ip6str[128];

  /* Name */
  printf("%s\n",d->name);

  /* Description */
  if (d->description)
    printf("\tDescription: %s\n",d->description);

  /* Loopback Address*/
  printf("\tLoopback: %s\n",(d->flags & PCAP_IF_LOOPBACK)?"yes":"no");

  /* IP addresses */
  for(a=d->addresses;a;a=a->next) {
    printf("\tAddress Family: #%d\n",a->addr->sa_family);

    switch(a->addr->sa_family)
    {
      case AF_INET:
        printf("\tAddress Family Name: AF_INET\n");
        if (a->addr)
          printf("\tAddress: %s\n",iptos(((struct sockaddr_in *)a->addr)->sin_addr.s_addr));
        if (a->netmask)
          printf("\tNetmask: %s\n",iptos(((struct sockaddr_in *)a->netmask)->sin_addr.s_addr));
        if (a->broadaddr)
          printf("\tBroadcast Address: %s\n",iptos(((struct sockaddr_in *)a->broadaddr)->sin_addr.s_addr));
        if (a->dstaddr)
          printf("\tDestination Address: %s\n",iptos(((struct sockaddr_in *)a->dstaddr)->sin_addr.s_addr));
        break;

	  case AF_INET6:
       printf("\tAddress Family Name: AF_INET6\n");
#ifndef __MINGW32__ /* Cygnus doesn't have IPv6 */
        if (a->addr)
          printf("\tAddress: %s\n", ip6tos(a->addr, ip6str, sizeof(ip6str)));
#endif
		break;

	  default:
        printf("\tAddress Family Name: Unknown\n");
        break;
    }
  }
  printf("\n");
}

/* From tcptraceroute, convert a numeric IP address to a string */
#define IPTOSBUFFERS	12
char *iptos(u_long in)
{
	static char output[IPTOSBUFFERS][3*4+3+1];
	static short which;
	u_char *p;

	p = (u_char *)∈
	which = (which + 1 == IPTOSBUFFERS ? 0 : which + 1);
	sprintf(output[which], "%d.%d.%d.%d", p[0], p[1], p[2], p[3]);
	return output[which];
}

#ifndef __MINGW32__ /* Cygnus doesn't have IPv6 */
char* ip6tos(struct sockaddr *sockaddr, char *address, int addrlen)
{
	socklen_t sockaddrlen;

	#ifdef WIN32
	sockaddrlen = sizeof(struct sockaddr_in6);
	#else
	sockaddrlen = sizeof(struct sockaddr_storage);
	#endif

	if(getnameinfo(sockaddr,
		sockaddrlen,
		address,
		addrlen,
		NULL,
		0,
		NI_NUMERICHOST) != 0) address = NULL;

	return address;
}
#endif /* __MINGW32__ */

我用VS2010调试出现的问题下：
错误 1 error LNK2019: 无法解析的外部符号 _pcap_freealldevs，该符号在函数 _main 中被引用
错误 2 error LNK2019: 无法解析的外部符号 _pcap_findalldevs，该符号在函数 _main 中被引用
错误 3 error LNK2019: 无法解析的外部符号 __imp__getnameinfo@28，该符号在函数 "char * __cdecl ip6tos(struct sockaddr *,char *,int)" (?ip6tos@@YAPADPAUsockaddr@@PADH@Z) 中被引用
错误 4 error LNK1120: 3 个无法解析的外部命令


说明，此程序要安装Wincap4_1_2 以及相关sdk开发包。


谢谢各位大神了！

[xiaohuh421]

1.可能是对应的库没有包含到工程中.
2.库版本不对,没有_pcap_freealldevs或者参数不匹配.所以link是查不到.

[君记否]

你没包含相应版本的lib文件

[xiaochangcong123]

额~最近被各种各样的事情搞得太乱了。
导致昨晚鼓捣了好久没成。
纠结了好久~


现在已解决了。
将开发包中的库文件放到VS相应的安装目录下
然后在程序中加入
#pragma comment(lib,"wpcap.lib")
#pragma comment(lib,"ws2_32.lib")

//wpcap.lib  ws2_32.lib包含 在开发包中

谢谢。

另外，各位能否说说VS08以及以前版本中对IPV6地址的支持，该怎么解决呢

[贲于丘园]

已解决问题，感谢！