在嵌入式系統(tǒng)中，使用goahead的時(shí)候， 以下代碼是獲取不到正確的ip地址的：
- if (gethostname(host, sizeof(host)) < 0) {
- error(E_L, E_LOG, T("Can't get hostname"));
- return -1;
- }
- if ((hp = gethostbyname(host)) == NULL) {
- error(E_L, E_LOG, T("Can't get host address"));
- return -1;
- }
- memcpy((char *) &intaddr, (char *) hp->h_addr_list[0],
- (size_t) hp->h_length);
可以結(jié)合以下兩個(gè)接口函數(shù)去獲取需要的ip地址：
- #include <sys/socket.h>
- #include <sys/ioctl.h>
- #include <arpa/inet.h>
- #include <netinet/in.h>
- #include <net/if.h>
- #include <stdlib.h>
- #include <string.h>
- #include <stdio.h>
- static int getIfaceName(char *iface_name, int len)
- {
- int r = -1;
- int flgs, ref, use, metric, mtu, win, ir;
- unsigned long int d, g, m;
- char devname[20];
- FILE *fp = NULL;
- if((fp = fopen("/proc/net/route", "r")) == NULL) {
- perror("fopen error!\n");
- return -1;
- }
- if (fscanf(fp, "%*[^\n]\n") < 0) {
- fclose(fp);
- return -1;
- }
- while (1) {
- r = fscanf(fp, "%19s%lx%lx%X%d%d%d%lx%d%d%d\n",
- devname, &d, &g, &flgs, &ref, &use,
- &metric, &m, &mtu, &win, &ir);
- if (r != 11) {
- if ((r < 0) && feof(fp)) {
- break;
- }
- continue;
- }
- strncpy(iface_name, devname, len);
- fclose(fp);
- return 0;
- }
- fclose(fp);
- return -1;
- }
- static int getIpAddress(char *iface_name, char *ip_addr, int len)
- {
- int sockfd = -1;
- struct ifreq ifr;
- struct sockaddr_in *addr = NULL;
- memset(&ifr, 0, sizeof(struct ifreq));
- strcpy(ifr.ifr_name, iface_name);
- addr = (struct sockaddr_in *)&ifr.ifr_addr;
- addr->sin_family = AF_INET;
- if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
- perror("create socket error!\n");
- return -1;
- }
-
- if (ioctl(sockfd, SIOCGIFADDR, &ifr) == 0) {
- strncpy(ip_addr, inet_ntoa(addr->sin_addr), len);
- close(sockfd);
- return 0;
- }
- close(sockfd);
- return -1;
- }
- int main(int argc, char** argv)
- {
- struct in_addr intaddr;
- char iface_name[20];
- if(getIfaceName(iface_name, sizeof(iface_name)) < 0) {
- printf("get interface name error!\n");
- return -1;
- }
- if(getIpAddress(iface_name, (char *) &intaddr, 15) < 0) {
- printf("get interface ip address error!\n");
- return -1;
- }
-
- printf("address:%s\n",(char *) &intaddr);
- return 0;
- }
