I'd just avoid this situation. Unless you're in a crowded room etc it's going to be hard for a guy to get me in this situation. But let's assume I'm there, two things come to mind immediately 1. Control his knife hand, break his hold with headbutts or right hooks, push off him pull firearm and shoot until he dies. 2. Control knife hand, pull firearm with other hand and fire close range. If I find myself in this situation without a firearm I'd probably fight for control of the knife, 1st thing would be to control the knife, punches, groin strikes, eye gouges if I could get the knife all the way to the side I'd try to take the guy down and if I got him down that's where I'd kill him and if not I'd chase his ass down and end him where ever. End of the day he pulled a knife on me and he's gotta die. I can't help but think next time it would be my wife and child with that knife on them or my mom. Don't get me wrong I'll give a guy a ride, hot meal and 20$ if asked but if he wants to take 5$ by force that's the only way he'll take it from me.
But for everyone else who is not so arrogant and blinded by anger, I'd say always cooperate and give him your stuff, and if they aren't going to let you go then run. An attacker with a knife is a lot more dangerous than a normal attacker. The truth is that an attacker with a knife will probably kill you in a fight.
If a law is unjust, a man is not only right to disobey it, he is obligated to do so. ~ Thomas Jefferson
Sig by D.P.