Programming

#ifdef __STDC__
#define PROTOTYPICAL
#endif
#ifdef __cplusplus
#define PROTOTYPICAL
#endif

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <netdb.h>
#include <arpa/inet.h>


#ifdef PROTOTYPICAL
int main(int argc, char *argv[])
#else
main(argc,argv)
char *argv[];
#endif
{
	char *mess;
	struct hostent *hp;
	int dumpall;

	dumpall=0;
	while(*++argv) {
		if(!strcmp(*argv,(char *)"-d")) {
			dumpall=!dumpall;
			continue;
		}
		/*
		 *  Call gethostbyname for current argument
		 */
		if(! (hp = gethostbyname(*argv))) {
			switch(h_errno){
					case HOST_NOT_FOUND:  
						mess=(char *)"Not Found";
						break;
					case TRY_AGAIN:  
						mess=(char *)"Time Out";
						break;
					case NO_RECOVERY:  
						mess=(char *)"No Recovery";
						break;
					case NO_ADDRESS:  
						mess=(char *)"No Address";
						break;
					default: 
						mess=(char *)"unknown error";
						break;
			}
			printf("%s  %s\n", *argv, mess);

		} else {
			printf("%s  %s  %s \n", *argv, hp->h_name,
				inet_ntoa(*(struct in_addr *)(hp->h_addr)));
			if(dumpall) {
				printf("  addresses:\n");
				while(*(hp->h_addr_list)){
					printf("      %s \n", 
						inet_ntoa(*(struct in_addr *)*(hp->h_addr_list)++));
				}
				printf("  aliases:\n");
				while(*(hp->h_aliases)){
					printf("      %s \n",*(hp->h_aliases)++);
				} 
			}
		}
	}
	exit(0);
}