in reply to Multiplexed TCP-Client (from: Networkprogramming with Perl)

Your code works fine for me Linux 2.4, perl 5.6.1. Here is how it goes: 
1009% perl  index.pl
starting loop
45  # <- I typed a 45, then enter
STDIN ready
STDIN ready
STDIN ready
SOCKET ready
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<HTML><HEAD>
<TITLE>403 Forbidden</TITLE>
</HEAD><BODY>
<H1>Forbidden</H1>
You don't have permission to access /
on this server.<P>
<HR>
<ADDRESS>Apache-AdvancedExtranetServer/1.3.23 Server at xxx.xxx.xxx Po
+rt 80</ADDRESS>
</BODY></HTML>
STDIN ready
SOCKET ready
Connection closed by foreign host

[download]
Note here that the web server gives 'Permission denied', but it does receive the message.

-Mark

In Section Seekers of Perl Wisdom