> No, it doesn't. What purpose would that serve? It will cost you a buffer > for the I/O (perhaps 8192 bytes) and a FILE control structure. If I remember rightly its nearer 64K nowdays simply because disks are faster, memory is cheaper and its a good buffer size. Basically the C library will make an intelligent decision on buffering which you should assume is right exept in very special cases. That value may change depending on library version, kernel, system memory, OS and a million other things but its there in the library to save you having to worry about it in the app. If you need to do specific buffering see "man setbuf" Alan