Add tests. They are quite basic ...

agentx/agentx_test.go

@@ -0,0 +1,53 @@
+// Copyright 2025, IPng Networks GmbH, Pim van Pelt <pim@ipng.ch>
+
+package agentx
+
+import (
+	"flag"
+	"testing"
+)
+
+func TestAgentXAddrFlag(t *testing.T) {
+	// Test that the flag is registered with correct default
+	if *AgentXAddr != "localhost:705" {
+		t.Errorf("Expected default AgentX address to be 'localhost:705', got '%s'", *AgentXAddr)
+	}
+}
+
+func TestAgentXAddrFlagParsing(t *testing.T) {
+	// Save original flag value
+	originalAddr := *AgentXAddr
+	defer func() { *AgentXAddr = originalAddr }()
+
+	// Test Unix socket path
+	testAddr := "/var/run/test.sock"
+	*AgentXAddr = testAddr
+	
+	if *AgentXAddr != testAddr {
+		t.Errorf("Expected AgentX address to be '%s', got '%s'", testAddr, *AgentXAddr)
+	}
+
+	// Test TCP address
+	testAddr = "192.168.1.1:705"
+	*AgentXAddr = testAddr
+	
+	if *AgentXAddr != testAddr {
+		t.Errorf("Expected AgentX address to be '%s', got '%s'", testAddr, *AgentXAddr)
+	}
+}
+
+func TestFlagRegistration(t *testing.T) {
+	// Test that our flag is properly registered
+	f := flag.Lookup("agentx.addr")
+	if f == nil {
+		t.Error("Expected agentx.addr flag to be registered")
+	}
+	
+	if f.DefValue != "localhost:705" {
+		t.Errorf("Expected flag default value to be 'localhost:705', got '%s'", f.DefValue)
+	}
+	
+	if f.Usage != "Address to connect to (hostname:port or Unix socket path)" {
+		t.Errorf("Unexpected flag usage string: %s", f.Usage)
+	}
+}