How is it hangin'?

Putting on my best Noo Yewark accent, I asked the woman behind the counter: "Hey, how's it hangin'"? 

She was in absolutely no mood for nonsense. 

"What's your order?" she barked.

I lost my NY accent instantly.

But a few hours later, undeterred, I asked the check-out woman at another shop:

Me:                    Hey, how's it hangin'?
Check-out girl:  Pardon me?
Me:                    How's it hangin?
Check-out girl:  What's IT?
Me:                    Life, you know.  Things ...  How's it hangin?
Check-out girl:  I am sorry, I am not from this town.  It's probably a New York thing that I am not familiar with.
Me:                   Surely you must have heard the expression before!  Where're you from?
Check-out girl:  I am from California, I never heard that expression before.   We speak proper English in California.  Sorry.  It's probably a New York thing.  You New Yorkers have your own things.

I was so baffled, I shut up and paid. 

Mission accomplished, I guess (I wanted to pass myself off as a New Yorker).

I have now found out that the expression is rather inappropriate in its meaning and is supposed to be used by close male buddies.