62 lines
1.4 KiB
C
62 lines
1.4 KiB
C
#define _XOPEN_SOURCE 700
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#include <stdio.h>
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#include <string.h>
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#include <stdlib.h>
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#include <netdb.h>
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#include <sys/types.h>
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#include <sys/socket.h>
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#include <arpa/inet.h>
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#include <netinet/in.h>
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#define MAXSIZE 100
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int main(int argc, char *argv[])
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{
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struct addrinfo hints, *res, *result;
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char addrstr[MAXSIZE];
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char host[MAXSIZE];
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void *ptr;
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/* argument till programmet */
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if (argc == 2)
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{
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strncpy(host, argv[1], MAXSIZE);
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}
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else
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{
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printf("Please specify a host to lookup\n");
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return 1;
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}
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memset (&hints, 0, sizeof (hints)); /* nolla ut hints */
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hints.ai_family = AF_UNSPEC; /* både IPv4 och IPv6 */
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hints.ai_socktype = SOCK_STREAM;
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/* hämta IP */
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if ( getaddrinfo (host, NULL, &hints, &result) != 0 )
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{
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perror ("getaddrinfo");
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return 1;
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}
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res = result;
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while (res) /* loopa över alla IP-adresser */
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{
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switch (res->ai_family) /* IPv4 eller IPv6 */
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{
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case AF_INET: /* IPv4 */
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ptr = &((struct sockaddr_in *) res->ai_addr)->sin_addr;
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break;
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case AF_INET6: /* IPv6 */
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ptr = &((struct sockaddr_in6 *) res->ai_addr)->sin6_addr;
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break;
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}
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/* omvandla binär-IP till läslig IP-adress */
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inet_ntop (res->ai_family, ptr, addrstr, MAXSIZE);
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printf ("%s\n", addrstr);
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res = res->ai_next; /* nästa IP i listan */
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}
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freeaddrinfo(result); /* frigör minnet */
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return 0;
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}
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