Computation
hSetBuffering hdl mode sets the mode of
buffering for handle
hdl on subsequent reads and writes.
If the buffer mode is changed from
BlockBuffering or
LineBuffering to
NoBuffering, then
- if hdl is writable, the buffer is flushed as for
hFlush;
- if hdl is not writable, the contents of the buffer is
discarded.
This operation may fail with:
- isPermissionError if the handle has already been used for
reading or writing and the implementation does not allow the buffering
mode to be changed.