Open carry in NC is 'permitted' except where local laws prohibit the display of firearms. Open carry is not specifically legally permitted, actually, it just isn't specifically prohibited either, so the reason you find vague answers is that the law is rather vague.
Cary and Chapel Hill are two areas that prohibit display, but I only know of those since I live in the area, there may be more. State firearms laws can be found at the State Department of Justice website, Link Removed
See page 34, where it says "North Carolina law does not currently address specific age requirements for the purchase of weapons. Rather, it looks to the federal standards for such restrictions." Under federal law you cannot purchase a handgun from a Firearms Dealer at age 19. NC requires the sheriff of the county to issue a handgun purchase permit, however again from the NCDoJ website: "Therefore, while a pistol purchase permit can be issued to an individual 18 years of age or older, such persons aged 18, 19, and 20 could not use the permit to purchase a handgun from a federally licensed firearms dealer."
I'm not a lawyer, so I'm not sure exactly where that leaves you. To ME, that seems to mean you can legally possess a handgun (such as a gift or private purchase), you just can't BUY one from an FFL, but again, I'm not a lawyer. And if you can legally possess a handgun, you can, in theory, legally open carry. There are certainly some places that would cause more trouble than other places.
I am (very considerably) over 19, and sometimes I open carry in Raleigh suburbs (other than the town of Cary) and have gotten a few looks but no one freaked out and I've never been hassled by the police.
Edit: I should also note since you're a student (I'm faculty, so I'm familiar with the laws concerning campus) that you cannot open or concealed carry on any college campus, with or without a permit, although you may have a handgun (not a long gun) locked in your vehicle on campus if you have a Concealed Handgun Permit, but ONLY if you have the CHP.