## The client

## Connect to the server
my $server = IO::Socket::INET->new(
    'localhost:9999'
) or die $!;

## Set the socket non-blocking
ioctl( $server, 0x8004667e, \1 );

## Start a thread to recieve and display input from the server
async {
    my $in = '';
    while( 1 ) {
        ## Accumulate input and display when we've got a full line
        sysread( $server, $in, 100, length( $in ) );
        if( my $p = 1 + index $in, "\n" ) {
            printf 'C: %s', substr $in, 0, $p+1, '';
        }
        Win32::Sleep 100;
    }
};

## Give the threads a chance to start
sleep 2;

## The main thread reads from the keyboard and sends to the server.
while( <STDIN> ) {
    print $server $_;
}