Ummmm... no... the file pointer is the next position in the disk file... if it pointed at the buffer fseek() would be useless.
The first time you have to seek to position 8,000,000,000 on a system with 2gigs of ram, you'll understand that.
Most OSs will no longer permit low level disk I/O at the application level and for the most part it's downright silly to try to bypass the OS safeguards... one bad call and you end up reformatting your disks and reinstalling everything... NOT an acceptable risk.if you really need to read directly form disk you can use Low Level I/O.