/* ECE435: tespip.c
 * Change IP address to internal representation
 * Work at APPLICATION level
 * Compile using : gcc -o testip testip.c
 * Usage: testip 192.168.0.9
 */


#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <netdb.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <sys/socket.h>

#define PORT   3500

int main (int argc, char *argv[])
{
        struct hostent *he;
        struct sockaddr_in their_addr; // connector's address information 

        if (argc != 2) {
            fprintf(stderr,"usage: testip hostname\n");
            exit(1);
        }

        if ((he=gethostbyname(argv[1])) == NULL) {  // get the host info 
            perror("gethostbyname");
            exit(1);
        }

        their_addr.sin_family = AF_INET;    // host byte order 
        their_addr.sin_port = htons(PORT);  // short, network byte order 
        their_addr.sin_addr = *((struct in_addr *)he->h_addr);
        memset(&(their_addr.sin_zero), '\0', 8);  // zero the rest of the struct 

	printf("IP address : %s\n", argv[1]);
	printf("IP network number : %lu\n", their_addr.sin_addr.s_addr);

	exit(1);
}