It gets weird when you throw Linux in the mix - open/close are extremely cheap on Linux, to the point of being free - at least used to be before Spectre and Mel

It gets weird when you throw Linux in the mix - open/close are extremely cheap on Linux, to the point of being free - at least used to be before Spectre and Meltdown and what not. So on Linux doing n more open/closes isn't much different than doing a single pair if n is not humongous and the program is doing other things besides just open close.