Bug report

Bug description:

#126606 fixed a bug, in that writing incomplete .pyc files is not going to end well for the system.
But the solution was just to crash the file write, not attempt any retries.

It's not completely unexpected to receive a signal or some other interrupt that results in write() not writing all the provided data. This can be handled.

We've observed incomplete .pyc files in the past in Debian systems, and I just ran into this in a CI job:

https://people.debian.org/~stefanor/upstream/debusine-server_0.13.1.log

  Setting up python3-debusine-server (0.13.1) ...
  os.write() didn't write the full pyc filedpkg: error processing package python3-debusine-server (--configure):
   installed python3-debusine-server package post-installation script subprocess returned error exit status 1

CPython versions tested on:

CPython main branch

Operating systems tested on:

Linux

Linked PRs

• gh-141930: Use the regular IO stack to write .pyc files for a better error message on failure #141931
• [3.14] gh-141930: Use the regular IO stack to write .pyc files for a better error message on failure (GH-141931) #142021
• [3.13] gh-141930: Use the regular IO stack to write .pyc files for a better error message on failure (GH-141931) #142023