本文共 3104 字,大约阅读时间需要 10 分钟。
在实际的项目运用中,我们往往需要绑定本机的IP和端口号,或者作为服务器需要将自己的IP信息更新至数据库中,便于其他其中通过查询数据库得到地址从而发数据,如果我们把它做成智能的获取本机的IP,这样我们的代码的可移植性就提高了。下面就介绍一种在windows和linux下面可以智能获取我们本机的局域网IP的方法,不妥之处还请大家多多指教。
(1)Windows
#include "winsock2.h"#pragma comment(lib, "ws2_32.lib")int GetLocalIP(char *ip){ WSADATA wsaData; char name[155]; PHOSTENT hostinfo; if (WSAStartup(MAKEWORD(2, 0), &wsaData) == 0) { if (gethostname(name, sizeof(name)) == 0) { if ((hostinfo = gethostbyname(name)) != NULL) { ip = inet_ntoa(*(struct in_addr *)*hostinfo->h_addr_list); printf("local ip : %s\n", ip); } } WSACleanup(); } return 1;}int main(int argc, char argv[]){ char getip[64] = { 0 }; GetLocalIP(getip); return 0;}
(2)Linux
#include#include #include #include #include #include #include #include #include #include #include int GetLocalIP(char *ip){ int MAXINTERFACES = 16; int fd, intrface = 0; struct ifreq buf[MAXINTERFACES]; ///if.h struct ifconf ifc; ///if.h if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) >= 0) //socket.h { ifc.ifc_len = sizeof buf; ifc.ifc_buf = (caddr_t)buf; if (!ioctl(fd, SIOCGIFCONF, (char *)&ifc)) //ioctl.h { intrface = ifc.ifc_len / sizeof (struct ifreq); while (intrface-- > 0) { if (!(ioctl(fd, SIOCGIFADDR, (char *)&buf[intrface]))) { sprintf(ip, "%s", inet_ntoa(((struct sockaddr_in*)(&buf[intrface].ifr_addr))->sin_addr)); printf("ip:%s\n", ip); break; } } } close(fd); } return 0;}
该程序可以直接运行,已经在两个平台中测试验证通过!!!
const char * GetLocalAddr(char *ifaddr, size_t ifaddr_size){ char *ifaddr_data = NULL;#ifdef WIN32 char hostname[155]; PHOSTENT hostinfo; if (gethostname(hostname, sizeof(hostname)) == 0) { if ((hostinfo = gethostbyname(hostname)) != NULL) { ifaddr_data = strncpy(ifaddr, inet_ntoa(*(struct in_addr *)*hostinfo->h_addr_list), ifaddr_size); } }#else int MAXINTERFACES = 16; int fd, intrface = 0; struct ifreq buf[MAXINTERFACES]; ///if.h struct ifconf ifc; ///if.h if ((fd = socket(AF_INET, SOCK_DGRAM, 0)) >= 0) //socket.h { ifc.ifc_len = sizeof(buf); ifc.ifc_buf = (caddr_t)buf; if (!ioctl(fd, SIOCGIFCONF, (char *)&ifc)) //ioctl.h { intrface = ifc.ifc_len / sizeof(struct ifreq); for (int i = 0; i < intrface; i++) { struct ifreq * lp_ifc_req = &buf[i]; char if_name[32] = { 0 }; strncpy(if_name, lp_ifc_req->ifr_name, sizeof(if_name)); int if_flag = 0; ioctl(fd, SIOCGIFFLAGS, lp_ifc_req); if_flag = lp_ifc_req->ifr_flags; char if_addr[32] = { 0 }; ioctl(fd, SIOCGIFADDR, lp_ifc_req); inet_ntop(AF_INET, &(((struct sockaddr_in *)&(lp_ifc_req->ifr_addr))->sin_addr), if_addr, sizeof(if_addr));#if 1 printf("%2d: ifr_name=%s, ifr_flags= 0x%x, ifr_addr= %s\n", i, if_name, if_flag, if_addr);#endif#define IFF_NET_RUNNING (IFF_UP | IFF_BROADCAST | IFF_MULTICAST | IFF_RUNNING) if ((if_flag & IFF_LOOPBACK) == (IFF_LOOPBACK) || (if_flag & IFF_NET_RUNNING) != IFF_NET_RUNNING) continue; ifaddr_data = strncpy(ifaddr, if_addr, ifaddr_size); break; } } close(fd); }#endif // WIN32 return ifaddr_data;}
转载地址:http://njqxi.baihongyu.com/