Binding using socket call gethostbyname

Figure 1 shows another example of socket call bind(). It uses the utility routine gethostbyname() to find the internet address of the host, rather than using socket call inet_addr with a specific address.

Figure 1. A bind() call using gethostbyname()

int bind(int s, struct sockaddr *name, int namelen);
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int rc;
int s;
char *hostname = “myhost”;
struct sockaddr_in myname;
struct hostent *hp;
 
   hp = gethostbyname(hostname);
 
   /* clear the structure to clear the sin_zero field */
   memset(&myname,0,sizeof(myname));
   myname.sin_family = AF_INET;
   myname.sin_addr.s_addr = *((unsigned long *)hp->h_addr);
   myname.sin_port = htons(1024);
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rc = bind(s,(struct sockaddr *) &myname, sizeof(myname));