Avoiding Buffering in a Python File Library

Question

Avoiding Buffering in a Python File Library

I saw this question asked here, but the answers received did not work in my case and were marked as duplicates.

python -unot working for stdinin Python 3.
sys.stdin = sys.stdin.detach()issues a ValueError: underlying buffer has been detached.
None of them work for inputs stdinand other files used as a stream.
Adding a hook does not work: FileInput(openhook=hook_nobuf)and using open(buffering=0)in hook.

I dug up the source code ( /usr/lib/python3.2/fileinput.py) and saw what was readlines(bufsize)used internally to load the buffer. No sink or other piping shuntigans.

+5

python file-io readlines readline buffering

Sumant manne Feb 21 '13 at 21:13

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1 answer

Sumant Manne · Accepted Answer · 2013-02-21T21:13:48+0000

, FileInput(bufsize=1). file.readlines() " , , ". , , .

with fileinput.input(bufsize=1) as f:
    for line in f:
        print("One line in, one line out!")

Avoiding Buffering in a Python File Library

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