Unix Socket Programming Question:

After accept()ing a connection, use getpeername() to get the address of the client. The client's address is of course, also returned on the accept(), but it is essential to initialise the address-length parameter before the accept call for this will work.

int t;
int len;
struct sockaddr_in sin;
struct hostent *host;

len = sizeof sin;
if (getpeername(t, (struct sockaddr *)
&sin, &len) < 0)
perror("getpeername");
else {
if ((host = gethostbyaddr((char *)
&sin.sin_addr,sizeof sin.sin_addr,
AF_INET)) == NULL)
perror("gethostbyaddr");
else printf("remote host is '%s'n",
host->h_name);
}