Checking serial number on a gun

This post in conjunction with a personal discussion I was having earlier today got me wondering... How can law enforcement officers check the serial number of a gun to see if it's stolen, unless you've already done something to give them probable cause for a search? I can understand why LEO's might temporarily disarm someone for safety at a traffic stop or similar circumstances, but it seems to me that running the serial number without a warrant would be an unlawful search.

As a side note, what if I had a laptop computer on the passenger seat instead of a handgun? I've never heard of anyone having their laptop checked to see if it's stolen at a traffic stop. Maybe it has happened and I just never heard the story?

Road block in SC as the DD for some of us that had been to Darlington. The owner of the suburban was riding shotgun (drunk but it was his truck). I don't drink at the race, waste of good money. When they asked for registration, the drunk went to open the glove box even when I told him it was locked (talking sense to a drunk is a waste of time). I had earlier made sure it was locked but he unlocked it at a gas stop (my mistake). The LEO on both side had their guns drawn but when he opened it, surprised me but I slammed it shut and told the officer there was a loaded .38 in there. He thanked me and opened the box, took it back to his cruiser and came back to my side. Thanked me again and asked I not load it until I was down the road. Last race I went to with the drunk.
Have been to road blocks before and told them I had a firearm when asked if I had anything in the car. They never even asked to see it.
So I guess it depends, I think he probable cause in the first case. In the others where they did not ask for the pistol, they did not have probable cause. Case by case I guess.

if the police came to your home on say, a barking dog complaint, would they have the right to start running numbers on every gun you have in the house. same difference

They run tag numbers on most cars they stop; or so I have been told.

Of course, tags are out there visible for all to see (except those folks who cover them with dark plastic.)

But I agree---there is no reason for them to check ALL guns they come across.

On the other hand, I am not sure they do.

Nor does it threaten me.

Kind of like I don't particularly like the idea that "they" listen to my phone calls, but they would just be bored to death.