Description

assignee = None
closed_at = None
created_at = <Date 2021-03-07.23:29:06.867>
labels = ['extension-modules', 'type-bug', '3.10']
title = 'mmap.size() raises OSError on Unix for anonymous memory'
updated_at = <Date 2021-03-07.23:33:14.666>
user = 'https://github.com/ZackerySpytz'

activity = <Date 2021-03-07.23:33:14.666>
actor = 'ZackerySpytz'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Extension Modules']
creation = <Date 2021-03-07.23:29:06.867>
creator = 'ZackerySpytz'
dependencies = []
files = []
hgrepos = []
issue_num = 43429
keywords = ['patch']
message_count = 1.0
messages = ['388252']
nosy_count = 1.0
nosy_names = ['ZackerySpytz']
pr_nums = ['24781']
priority = 'normal'
resolution = None
stage = 'patch review'
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue43429'
versions = ['Python 3.10']

Activity

1. ZackerySpytz commented on Mar 7, 2021

   

   ZackerySpytzmannequin

   on Mar 7, 2021

   MannequinAuthor

   More actions

   For anonymous memory, mmap.size() works without issue on Windows, but it raises OSError on Unix.
2. ZackerySpytz

   added

   3.10 (EOL)end of lifeend of life

   extension-modulesC modules in the Modules dirC modules in the Modules dir

   type-bugAn unexpected behavior, bug, or errorAn unexpected behavior, bug, or error

   on Mar 7, 2021
3. ezio-melotti

   transferred this issue fromon Apr 10, 2022
4. arhadthedev

   added

   3.11only security fixesonly security fixes

   3.12only security fixesonly security fixes

   and removed

   3.10 (EOL)end of lifeend of life

   on May 12, 2023
5. serhiy-storchaka commented on Aug 29, 2025

   

   serhiy-storchaka

   on Aug 29, 2025

   Member

   More actions

   The question is whether this should be classified as a bug fix or a new feature. It seems that mmap.size() never worked for anonymous mapping on Unix, so there is no user code that depends on it. Although this limitation was not documented.

   There are now two PRs, #24781 and #138198. The former adds this as a new feature and has more documentation, the latter treat it as a bug fix and takes into account trackfd.

   I think we should go with #24781, after it was updated.

   Reacted by Petr Viktorin
6. serhiy-storchaka

   added

   type-featureA feature request or enhancementA feature request or enhancement

   3.15bugs and security fixesbugs and security fixes

   and removed

   type-bugAn unexpected behavior, bug, or errorAn unexpected behavior, bug, or error

   3.11only security fixesonly security fixes

   3.12only security fixesonly security fixes

   on Aug 29, 2025
7. serhiy-storchaka

   added a commit that references this issue on Sep 2, 2025

   gh-87595: Support mmap.size() for anonymous mapping on Unix (GH-24781)

   32032ee
8. miss-islington

   added 2 commits that reference this issue on Sep 2, 2025

   pythongh-87595: Support mmap.size() for anonymous mapping on Unix (py…

   147eb94

   pythongh-87595: Support mmap.size() for anonymous mapping on Unix (py…

   8c45634
9. serhiy-storchaka

   closed this as completedon Sep 2, 2025
10. serhiy-storchaka commented on Sep 2, 2025

    

    serhiy-storchaka

    on Sep 2, 2025

    Member

    More actions

    Also, it was decided in the discussion for #138238 that it is better to raise a dedicated error for trackfd=False instead of triggering an OSError by passing invalid handler or descriptor to the OS API.
11. ZackerySpytz

    added a commit that references this issue on Sep 4, 2025

    pythongh-87595: Fix the docs for mmap.size()

    5e23194
12. vstinner

    added a commit that references this issue on Sep 4, 2025

    gh-87595: Fix the docs for mmap.size() (#138494)

    9d6b94a
13. lkollar

    added 2 commits that reference this issue on Sep 9, 2025

    pythongh-87595: Support mmap.size() for anonymous mapping on Unix (py…

    9869e76

    pythongh-87595: Fix the docs for mmap.size() (python#138494)

    85fe034

Issue actions