1 #include <netdb.h>
2 #include <stdio.h>
3 #include <unistd.h>
4 #include <stdlib.h>
5 #include <arpa/inet.h>
6 #include <netdb.h>
7
8 void error_handling(char *msg);
9
10 int main(int argc,char **argv)
11 {
12 int i;
13
14 struct hostent *host;
15 if (argc != 2) {
16 printf("Usage :%s <addr>\n",argv[0]);
17 exit(1);
18 }
19
20 host = gethostbyname(argv[1]);
21 if (!host) {
22 error_handling("gethost err");
23 }
24
25 for (i = 0;host->h_aliases[i];i++) {
26 printf("alias : %d <%s>\n",i,host->h_aliases[i]);
27 }
28 for (i = 0;host->h_addr_list[i];i++) {
29 printf("ip : %d <%s>\n",i,inet_ntoa(*(struct in_addr*)host->h_addr_list[i]));
30 }
31
32 return 0;
33 }
34
35
36 void error_handling(char *msg)
37 {
38 fputs(msg,stderr);
39 fputc('\n',stderr);
40 exit(1);
41 }
