Error in keyboard_command.cpp Sending custom messages from mavros to PX4

Hello, @LorenzMeier, @Jaeyoung-Lim @JonasVautherin @JulianOes @jimdgit
I have tried the procedure to create custom messages from Mavros to Mavlink
I am facing the following error when i tried to build my code using catkin_make in my workspace

here is the keyboard_command.cpp

please tell me how to solve this error

It’s pretty rude to @ mention people like that.

My apologies for mentioning you and other people.I am a little bit inexperienced in this field.I saw someone else’s message or doubt posted here mentioning you and others, I thought it would be faster to solve my error.I am again sorry for mentioning you and your team.

So you’re trying to add a custom message? Taking a step back, what are you trying to achieve, high level?

Yes, I am trying to add a custom messages. As I said, I am new to this field and i was just exploring it. If you could guide me or help me solve this error then I would be grateful.

My apologies if I am asking for more, but I want you to guide me.

Which procedure is that? Did you follow a guide somewhere? Can you link it so that we know what you have tried?

Again, what’s the high level goal? If we understand that, we are more likely to be able to help you. A custom message is usually the very last resort because it’s a bit of a pain to do.