If you're 43, you should know what you want to do. If you want to code, go for a senior/principal programming lead position. If you want to manage, go for a managerial position. You're asking a question a 20 yr old should be asking which makes me extremely worried what the future has in store for me. I hope that when I turn 40 in 2029, I could still do what I love (which happens to be in programming), and not have to fret if I need to change professions or not...this is the way.
*Edit, I hope I don't sound like a jerk, but this is really what I feel. I hope when millennials like me start to hit 40, we can change the tech industry's age distribution and we no longer have to worry about problems like this.