Find IP address from remote end of a TCP socket

In C or C++ it is fairly simple to find the IP address of the remote end of a TCP socket.
The following example shows how to do this using the getpeername() and inet_ntoa() system calls.

int sockfd;
int len;
char * hostip;
struct sockaddr_in sin;

len = sizeof(sin);

if (0 != getpeername(sockfd, (struct sockaddr *) &sin, &len))
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