Docs: problem with page "msvcrt — Useful routines from the MS VC runtime" #159072

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1. picnixz

   added

   docsDocumentation in the Doc dirDocumentation in the Doc dir

   on Oct 9, 2026
2. github-project-automation

   added this to docs issueson Oct 9, 2026
3. jikekei commented on Oct 10, 2026

   

   jikekei

   on Oct 10, 2026

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   I can reproduce this in a Windows console.

   Environment:

   • Windows version: 10.0.26200.9457
   • CPython 3.14.7, 64-bit (AMD64), MSC v.1944

   Reproducer:

   import msvcrt
   import sys
   
   print(sys.version)
   print("Received:", repr(msvcrt.getch()))

   Pressing Ctrl+C while getch() is waiting returns:

   Received: b'\x03'
   

   Ordinary letter keys are also returned as expected, such as b'd' and b'c'.

   This contradicts the documentation statement that the Control-C keypress cannot be read with this function. I would like to work on a documentation fix.
4. picnixz commented on Oct 10, 2026

   

   picnixz

   on Oct 10, 2026

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   I think the docs mean that Ctrl+C is not sending SIGINT to the terminal, not that it is not read.
5. picnixz commented on Oct 10, 2026

   

   picnixz

   on Oct 10, 2026

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   Wait if it is Windows, does Ctrl+C even work?
6. jikekei commented on Oct 10, 2026

   

   jikekei

   on Oct 10, 2026

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   Yes, Ctrl+C does work in Python on Windows, although reading it as a character and triggering an interrupt are different behaviors.
   In my manual test on Windows 10.0.26200.9457 with CPython 3.14.7, pressing Ctrl+C while msvcrt.getch() was waiting returned b'\x03' without raising KeyboardInterrupt.
7. picnixz commented on Oct 10, 2026

   

   picnixz

   on Oct 10, 2026

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   I think this is what the docs meant here. So they should be corrected accordingly to that I think. What about signal handlers? (does it even work on Windows?)
8. jikekei commented on Oct 10, 2026

   

   jikekei

   on Oct 10, 2026

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   Thanks for pointing out that distinction. I tested this with a custom handler registered using signal.signal(signal.SIGINT, handler) on Windows 10.0.26200.9457 with CPython 3.14.7.

   Pressing Ctrl+C while msvcrt.getch() was waiting returned b'\x03', and the handler was not called. As a comparison, pressing Ctrl+C while input() was waiting called the handler with SIGINT (2), after which input() raised EOFError.

   So SIGINT handlers do work on Windows in this test. I agree that the documentation should distinguish reading the Ctrl+C character from triggering interrupt handling.
9. jikekei

   added a commit that references this issue on Oct 10, 2026

   pythongh-159072: Clarify Ctrl+C and SIGINT handler behavior

   ffd7cf0