Network Programming with Perl

Sending to Multiple Hosts

One of the nice features of UDP is that the same socket can be used to send to and receive messages from multiple hosts. To illustrate this, let's rewrite the daytime client so that it can ask for the time from multiple hosts.

The revised client reads a list of hostnames from the command line and sends a daytime request to each one. It then enters a loop in which it calls recv() repeatedly to read any responses returned by the server. The loop quits when the number of responses received matches the number of requests sent, or until a preset timeout occurs. As it receives each response, the client prints the name of the remote host and the time it returned. Figure 18.3 lists the code for the revised daytime client, ...