The optional *buffering* argument specifies the file's desired buffer size: 0
means unbuffered, 1 means line buffered, any other positive value means use a
- buffer of (approximately) that size. A negative *buffering* means to use the
- system default, which is usually line buffered for tty devices and fully
- buffered for other files. If omitted, the system default is used. [#]_
+ buffer of (approximately) that size (in bytes). A negative *buffering* means
+ to use the system default, which is usually line buffered for tty devices and
+ fully buffered for other files. If omitted, the system default is used. [#]_
Modes ``'r+'``, ``'w+'`` and ``'a+'`` open the file for updating (note that
``'w+'`` truncates the file). Append ``'b'`` to the mode to open the file in