(Perl) Check Internet Connectivity

Demonstrates an efficient way to test for Internet connectivity.

Chilkat Perl Downloads Perl Module for Windows, MacOS, Linux, Alpine Linux

use chilkat();

$success = 0;

$socket = chilkat::CkSocket->new();
# 1. Use a reliable Anycast IP. 
#    8.8.8.8 (Google) or 1.1.1.1 (Cloudflare) are the industry standards.
$targetIp = "8.8.8.8";

# 2. Use Port 53 (DNS). 
#    DNS servers typically listen on TCP Port 53 as well as UDP. 
#    (Alternatively, use port 443 if you suspect port 53 is blocked).
$port = 53;

# 3. Disable SSL (0). 
#    We are not doing a handshake, just a TCP connection.
$ssl = 0;

# 4. Short Timeout (1500ms).
#    If you can't reach Google in 1.5 seconds, the connection is 
#    likely too poor for practical use anyway.
$timeoutMs = 1500;

# Connect
$success = $socket->Connect($targetIp,$port,$ssl,$timeoutMs);
if ($success == 0) {
    print $socket->lastErrorText() . "\r\n";
    exit;
}

$socket->Close(10);

print "We have Internet connectivity." . "\r\n";