I can't tell if this guy is flirting with me.?

he is one of those guys that are like mean, but not mean, it is joking mean, one time i was talking to another friend and he comes up behind me and pushes me and is like sup punk??? and i think it is weird but we always see eachother around, and one time i saw him and i was with my friends and he came over and sat with me and we talked for a couple of minutes, and then he had to go, but he was like you know where to find me... there is more things, but i just can't tell. He is cool.