If you want faster I/O, you have to use primitives - calls that ask you to do more programming. C++ calls are not primitves, neither are the
calls in standard C - fopen, fread, etc.
The file routines in fcntl.h (open, read, etc.) are lower level primitives. And they are usually faster when there is a lot of I/O. These are the routines that are called by fopen, fread. But they require more twiddling from the programmer's point of view.
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