在linux下 获取，修改本机IP地址的两个函数

//获取本机IP地址函数

QString GetLocalIp(){ int sock_get_ip; char ipaddr[50]; struct sockaddr_in *sin; struct ifreq ifr_ip; if ((sock_get_ip=socket(AF_INET, SOCK_STREAM, 0)) == -1) { printf("socket create failse...GetLocalIp!/n"); return ""; } memset(&ifr_ip, 0, sizeof(ifr_ip)); strncpy(ifr_ip.ifr_name, "eth0", sizeof(ifr_ip.ifr_name) - 1); if( ioctl( sock_get_ip, SIOCGIFADDR, &ifr_ip) < 0 ) { return ""; } sin = (struct sockaddr_in *)&ifr_ip.ifr_addr; strcpy(ipaddr,inet_ntoa(sin->sin_addr)); printf("local ip:%s /n",ipaddr); close( sock_get_ip ); return QString( ipaddr );}  

//修改本机IP地址的函数

int SetLocalIp( const char *ipaddr ){ int sock_set_ip; struct sockaddr_in sin_set_ip; struct ifreq ifr_set_ip; bzero( &ifr_set_ip,sizeof(ifr_set_ip)); if( ipaddr == NULL ) return -1; if(sock_set_ip = socket( AF_INET, SOCK_STREAM, 0 ) == -1); { perror("socket create failse...SetLocalIp!/n"); return -1; } memset( &sin_set_ip, 0, sizeof(sin_set_ip)); strncpy(ifr_set_ip.ifr_name, "eth0", sizeof(ifr_set_ip.ifr_name)-1); sin_set_ip.sin_family = AF_INET; sin_set_ip.sin_addr.s_addr = inet_addr(ipaddr); memcpy( &ifr_set_ip.ifr_addr, &sin_set_ip, sizeof(sin_set_ip)); if( ioctl( sock_set_ip, SIOCSIFADDR, &ifr_set_ip) < 0 ) { perror( "Not setup interface/n"); return -1; } //设置激活标志 ifr_set_ip.ifr_flags |= IFF_UP |IFF_RUNNING; //get the status of the device if( ioctl( sock_set_ip, SIOCSIFFLAGS, &ifr_set_ip ) < 0 ) { perror("SIOCSIFFLAGS"); return -1; } close( sock_set_ip ); return 0;}