Issue 36294: io.BufferedIOBase returns None (original) (raw)

Issue36294

Created on 2019-03-14 16:03 by cykerway, last changed 2022-04-11 14:59 by admin. This issue is now closed.

Messages (2)
msg337941 - (view)	Author: Cyker Way (cykerway) *	Date: 2019-03-14 16:03
Document of [BufferedIOBase](https://docs.python.org/3/library/io.html#io.BufferedIOBase) says: > ...unlike their RawIOBase counterparts, they will never return None. But this example shows the above statement is not true: import io import os import sys os.set_blocking(sys.stdin.fileno(), False) print(isinstance(sys.stdin.buffer, io.BufferedIOBase)) print(sys.stdin.buffer.read()) Output: True None
msg337973 - (view)	Author: Martin Panter (martin.panter) *	Date: 2019-03-15 08:35
The general problem of non-blocking reads with BufferedIOBase is covered by Issue 13322. The documentation and implementations do not agree. I suggest to not rely on any particular behaviour reading BufferedIOBase objects in non-blocking mode. The problem of the concrete class BufferedReader (what “stdin.buffer” usually is) was also recently raised in Issue 35869.