sys.stdin.read() exits the REPL process when stdin is set to be non-blocking on 3.14
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type-bug
- Dominant language
- Python
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Description
Bug report
Bug description:
import sys
import os
os.set_blocking(sys.stdin.fileno(), False)
sys.stdin.read()
Just a weird side effect I found while ckecking out #109523 on Python 3.14 using the new REPL.
Running the code mentioned in #109523 raises a BlockingIOError and exits the REPL process.
Running the code from a script produces an error that is consistent with the previous report.
CPython versions tested on:
CPython main branch
Operating systems tested on:
Linux
Linked PRs
- gh-121689
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
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- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Reproduce the snippet in the new Python 3.14 REPL on Linux and compare it with running the same code as a script. Review the work linked as gh-121689 and verify that a BlockingIOError no longer exits the REPL process while script behavior remains consistent with the earlier report.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- python
- Domain
- cli, operating-systems
- Issue type
- Bug
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 25/100