From 01fcde89d7d56321078be1739e759fece61d0a2b Mon Sep 17 00:00:00 2001 From: "Miss Islington (bot)" <31488909+miss-islington@users.noreply.github.com> Date: Thu, 26 Nov 2020 16:51:54 -0800 Subject: [PATCH] bpo-17852: Doc: Fix the tutorial about closing files (GH-23135) Co-authored-by: Inada Naoki (cherry picked from commit c8aaf71dde4888864c0c351e2f935f87652c3d54) Co-authored-by: Volker-Weissmann <39418860+Volker-Weissmann@users.noreply.github.com> --- Doc/tutorial/inputoutput.rst | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/Doc/tutorial/inputoutput.rst b/Doc/tutorial/inputoutput.rst index 366a532e817..4e27cff83ce 100644 --- a/Doc/tutorial/inputoutput.rst +++ b/Doc/tutorial/inputoutput.rst @@ -329,11 +329,16 @@ equivalent :keyword:`try`\ -\ :keyword:`finally` blocks:: If you're not using the :keyword:`with` keyword, then you should call ``f.close()`` to close the file and immediately free up any system -resources used by it. If you don't explicitly close a file, Python's -garbage collector will eventually destroy the object and close the -open file for you, but the file may stay open for a while. Another -risk is that different Python implementations will do this clean-up at -different times. +resources used by it. + +.. warning:: + Calling ``f.write()`` without using the :keyword:`!with` keyword or calling + ``f.close()`` **might** result in the arguments + of ``f.write()`` not being completely written to the disk, even if the + program exits successfully. + +.. + See also https://bugs.python.org/issue17852 After a file object is closed, either by a :keyword:`with` statement or by calling ``f.close()``, attempts to use the file object will