TCP Server with multiple connections in PERL based on specific code

Question

i use a Perl script to create a TCP server. It works fine, but i need to modify it so it accepts multiple connections. This is the code i use:

use IO::Socket::INET;

# auto-flush on socket
$| = 1;

# creating a listening socket
my $socket = new IO::Socket::INET (
    LocalHost => '0.0.0.0',
    LocalPort => '5000',
    Proto => 'tcp',
    Listen => 5,
    Reuse => 1
);
die "cannot create socket $!\n" unless $socket;
print "server waiting for client connection on port 5000\n";

while(1)
{
    # waiting for a new client connection
    my $client_socket = $socket->accept();

    # get information about a newly connected client
    my $client_address = $client_socket->peerhost();
    my $client_port = $client_socket->peerport();
    print "connection from $client_address:$client_port\n";

    # read up to 1024 characters from the connected client
    my $data = ":123456F#";

    $client_socket->send($data);

    # write response data to the connected client
    $data = "";
    $client_socket->recv($data, 1024);
    print "received data: $data\n";





    # notify client that response has been sent
    shutdown($client_socket, 1);
}

$socket->close();

I need to modify the above code in order to work for multiple connections. I'd really appreciate any help. Thanks

Answer 1

There are two key ways of handling multiple sockets.

The first is - making use of IO::Select - which has a can_read function - this allows you to test whether a socket has data to read, and you can just iterate your socket list. Read the doc on IO::Select, as it has an example of how to do exactly what you're wanting.

The other approach is parallel processing. Specifically using either threading or forking to handle the $client_socket asynchronously. I'll refer you to: Perl daemonize with child daemons (mostly because rewriting parallel code is a bit more convoluted, and so perhaps out of scope). I'd suggest you probably want a 'forking' approach, as that's generally better suited to the style of parallelism.