@item 0
Disable buffering of the selected stream.
-In this mode data is output immediately and only the
+In this mode, data is output immediately and only the
amount of data requested is read from input.
+Note the difference in function for input and output.
+Disabling buffering for input will not influence the responsiveness
+or blocking behavior of the stream input functions.
+For example @code{fread} will still block until @code{EOF} or error,
+even if the underlying @code{read} returns less data than requested.
@item @var{size}
Specify the size of the buffer to use in fully buffered mode.