What is the difference in buffered and non-buffered I/O ?

Buffered I/O read/write?

Hi all,

What's difference with buffered I/O and non-buffered I/O?
Is buffered I/O means:
And non-buffered I/O means:

Any suggestions will be appreciated!
Best regards,
Davy

Buffered I/O read/write?

In OS it is applied to input output streams . Writing to stream does not mean its immediate output to destination - data will be stored in stream buffer . but it is possible to order output by running flush() on that stream resulted in immediate output of data to its destination (file or console). It is done to optimize input output process to use less access hardware which is not sometimes immediately available. Let say hard drive head must be repositioned to correct sector and track and if it will be done on byte basis this will reduce speed of other applications trying to access that hard disk . Instead data is collected into blocks and block write is happened which replaces numerous byte writes by block write reducing harddisk head movements . Similar processes could take place on other than harddisk hardware as well.