Spostato il vecchi myhost.c e creato nuovo programma mygetaddr per provare

[gapil.git] / listati / mygetaddr.c

diff --git a/listati/mygetaddr.c b/listati/mygetaddr.c
new file mode 100644 (file)
index 0000000..1499e2b
--- /dev/null
+++ b/listati/mygetaddr.c
@@ -0,0 +1,56 @@
+    struct addrinfo hint;
+    struct addrinfo *res, *ptr;
+    int ret, port;
+    struct sockaddr_in *addr;
+    struct sockaddr_in6 *addr6;
+    char buffer[INET6_ADDRSTRLEN];
+    char *string;
+    ...
+    if ((argc - optind) != 2) {
+       printf("Wrong number of arguments %d\n", argc - optind);
+        usage();
+    }
+/* main body */
+    ret = getaddrinfo(argv[1], argv[2], NULL, &res);
+    if (ret != 0) {
+       printf("Resolution error %s\n", gai_strerror(ret));
+       exit(1);
+    }
+    ptr = res;
+    printf("Canonical name %s\n", ptr->ai_canonname);
+    do {
+       if (ptr->ai_family == PF_INET) {
+           printf("IPv4 address: \n");
+           addr = (struct sockaddr_in *) ptr->ai_addr;
+           port = ntohs(addr->sin_port);
+           string = inet_ntop(addr->sin_family, &addr->sin_addr, 
+                              buffer, sizeof(buffer));
+       } else if (ptr->ai_family == PF_INET6) {
+           printf("IPv6 address: \n");
+           addr6 = (struct sockaddr_in *) ptr->ai_addr;
+           port = ntohs(addr6->sin6_port);
+           string = inet_ntop(addr6->sin6_family, &addr6->sin6_addr, 
+                              buffer, sizeof(buffer));
+       } else {
+           printf("Address family error\n");
+           exit(1);
+       }       
+       printf("\tIndirizzo %s\n", string);
+       printf("\tProtocollo %i\n", ptr->ai_protocol);
+       printf("\tPorta %i\n", port);
+       
+
+       ptr = ptr->ai_next;
+    } while (ptr != NULL);
+    exit(0);
+}
+/*
+ * routine to print usage info and exit
+ */
+void usage(void) {
+    printf("Program mygethost: do an hostname resolution \n");
+    printf("Usage:\n");
+    printf("  mygethost [-h] hostname service\n");
+    printf("  -h   print this help\n");
+    exit(1);
+}