int set_file_buffer
(int fp, int buffer)
set_file_buffer() sets the buffering for write operations on the given filepointer fp to buffer bytes. If buffer is 0 then write operations are unbuffered.
The function returns 0 on success, or EOF if the request cannot be honored.
Note that the default for any fopen with calling set_file_buffer is 8K.
See also fopen().