While the OP didn't mention anything about the code needing to handle multiple concurrent clients, adding that functionality is probably a good idea. I'd probably fork to handle concurrent clients. Probably something like this (untested): 
#!/usr/bin/perl -w

use IO::Select;
use IO::Socket;
use POSIX qw(WNOHANG);
use strict;

$|++;

my $port   = 9999;
my $server = IO::Socket::INET->new (
                 Proto     => 'tcp',
                 LocalPort => $port,
                 Listen    => SOMAXCONN,
                 Reuse     => 1);

(! $server) && die "Could not setup server - $!\n";
$server->autoflush(1);

while (my $client = $server->accept()) {
   my $kidPid;
   unless (defined($kidPid = fork())) {
      # error handling code here
   }
   if ($kidPid == 0) {
      my $request;
      my $selector = IO::Select->new($client);
      if ($selector->can_read(10)) {
         my $buffer;
         while (sysread($client, $buffer, 1024)) {
            $request .= $buffer;
         }
      } else {
         print "Selector *cannot* read or timed out after 10 seconds.\
+n";
         exit();
      }
      syswrite($client, $request);
      $client->shutdown(1);
      exit();
   }
   close($client);
   meetTheReaper();
}

sub meetTheReaper {
   # reap availible children
   while (waitpid(-1, WNOHANG) > 0) { }
}

[download]
-- vek --

In reply to Re: Re: socket - echo server by vek
in thread socket - echo server by Anonymous Monk

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