#include <stdio.h>                                                              
#include <netdb.h>                                                              
#include <errno.h>                                                              
#include <stdlib.h>                                                             
                                                                                
int main(int argc, char** argv) {                                               
   int i;                                                                       
   char hostname[80];                                                           
                                                                                
   if(gethostname(hostname, sizeof(hostname))) {                                
     perror("gethostname");                                                     
     return(1);                                                                 
   }                                                                            
   printf("Ich bin %s.\n", hostname);                                           
                                                                                
   for (i=1; i<argc; i++) {                                                     
     struct hostent * phostent = gethostbyname(argv[i]);                        
     char ** pa;                                                                
     if (!phostent) {                                                           
       herror(argv[i]);                                                         
       continue;                                                                
     }                                                                          
                                                                                
     printf ("%s known as %s alias", argv[i], phostent->h_name);                
     for(pa = phostent->h_aliases; pa && *pa; pa++) {                           
       printf (" %s", *pa);                                                     
     }                                                                          
                                                                                
     printf("\nAddress(%d):", phostent->h_length);                              
     for(pa = phostent->h_addr_list; pa && *pa; pa++) {                         
       int j;                                                                   
       printf (" ");                                                            
       for(j=0;;j++) {                                                          
         printf("%u", (unsigned char)(*pa)[j]);                                 
         if(j+1 >= phostent->h_length) break;                                   
         printf(".");                                                           
       }                                                                        
     }                                                                          
     printf("\n");                                                              
  }                                                                             
  return 0;                                                                     
}