The BUFFERED specifier indicates run-time library behavior following WRITE operations. It takes the following form:
|'NO'||Requests that the run-time library send output data to the file system after each WRITE operation.|
|'YES'||Requests that the run-time library accumulate
output data in its internal buffer, possibly
across several WRITE operations, before the data
is sent to the file system.
Buffering may improve run-time performance for output-intensive applications.
The default is 'NO'.
If BUFFERED='YES' is specified, the request may or may not be honored, depending on the output device and other file or connection characteristics.
If BLOCKSIZE and BUFFERCOUNT have been specified for OPEN, their product determines the size in bytes of the internal buffer. Otherwise, the default size of the internal buffer is 8192 bytes.
The internal buffer will grow to hold the largest single record but will never shrink.