if a guy asks if you have a boyfriend, could he be interested?

[BecauseI'mKool]

i have known this one guy since i was like 5 (im 21 now and he's 23) we use to live in the same apartment and go to the same elementary school and hang out everyday. we know eachothers family thats how close we were. but then i moved and we never seen eachother for years after that. we would speak a bit on facebook but not much. about 3 weeks ago i saw him in person at the mall and he gave me a hug and asked how i was doing and we spoke for like a good 10 minutes, then he asked if i had a boyfriend and i said no. but now im always wondering why he asked me that. was he just being nice and just wanted to know because we've known eachother for so long? or was he actually interested in me? it was weird because last week i randomly bumped into him again and we had another conversation and he asked me the same thing again.. please tell me what u think, thanks.