use v5.36;
...
# Connect in "blocking" mode
my $socket = IO::Socket::IP->new(
    PeerHost => '192.168.1.181',
    PeerPort => 12345,
    Proto => 'tcp',
);

if(!defined($socket)) {
    die("Connection failed");
}


# Switch to non-blocking send/receive mode so we can implement timeouts
$socket->blocking(0);

$socket->send("AT\n");
waitFor($socket, 'AT');
$socket->send("AT1122\n");
my $oid = waitFor($socket, 'AT%23=1234', 1);
...


sub waitFor($socket, $searchstring, $caseinsensitive = 0) {
    while(1) {
        my $line = readsocketline($socket, 20);
        if($casesensitive) {
            if($line =~ /$searchstring/i) {
                return $line;
            }
        } elsif($line =~ /$searchstring/) {
            return $line;
        }
    }
}

sub readsocketline($socket, $timeout = 30) {

    if(!defined($timeout) || !$timeout) {
        $timeout = 30;
    };

    my $failat = time + $timeout;

    my $line = '';
    while(1) {
        my $char = '';
        $socket->recv($char, 1);
        if(time > $failat) {
            die("Network timeout");
        }
        next if(!defined($char) || $char eq '');
        next if($char eq "\r");
        last if($char eq "\n");
        $failat = time + $timeout;
        $line .= $char;
    }

    return $line;
}