use strict;
use warnings;

use IO::Socket::SSL;
$IO::Socket::SSL::DEBUG = 3;

my $host = 'letsencrypt.org';

my $client = IO::Socket::SSL->new(
    # where to connect
    PeerHost => $host,
    PeerPort => "https",

    # -------- test this --------
    SSL_ocsp_mode => SSL_OCSP_NO_STAPLE,

    # certificate verification - VERIFY_PEER is default
    SSL_verify_mode => SSL_VERIFY_PEER,
) or die "failed connect or ssl handshake: $!,$SSL_ERROR";

# send and receive over SSL connection
print $client "GET / HTTP/1.0\r\n";
print $client "Host: $host\r\n\r\n";

print <$client>;