.NET 7 SDK's dotnet.exe change the attached terminal code page when its standard output is redirected

[Dragnalith]

Bug Description

dotnet.exe change the code page of the attached terminal to be 65001 (i.e UTF-8) when the standard output of the dotnet.exe process is redirected. (it does not occur with dotnet.exe of .Net 6 SDK)

Illustration:

Impact Of The Bug

This bug break our build.

The terminal code page is a global setting and changing it impacts how following process will run. In our case, it breaks our build system based on ninja. Indeed, our build system run both MSVC C++ compiler and dotnet.exe, and MSVC C++ compiler depends on the code page to decide on its stdout encoding. Having the MSVC C++ compiler encoding changing randomly in the middle of the build creates issues.

How To Visualize The Terminal Code Page

To understand the bug it is important to be able to display the current code page of the terminal. I have created simple ShowConsoleCP.exe tool to do so which call and display the result of GetConsoleCP() and GetConsoleOutputCP()'s Win32 API. The tool is available in this ReproCodePage.zip archive.

How To Reproduce The Bug

Simple way: you can run the run_repro.cmd script of ReproCodePage.zip

Detailed way:

1. Start a terminal
2. create a new dotnet project. (e.g dotnet new console HelloWorld)
3. visualize the current terminal code page (e.g use ShowConsoleCP.exe included in ReproCodePage.zip)
   • If the code page is 65001, set another code page and go back to step 3 (e.g run chcp 932)
4. build using dotnet and redirect its standard output. (e.g dotnet build HelloWorld > foo.txt)
5. Visualize the current terminal code page and noticed it is now 65001 instead of the one before

Further technical details

• I have been able to reproduce the bug using various process creation api and stdout redirection:
  • using cmd.exe > symbol to redirect to file
  • using python and creation the dotnet.exe process with python's subprocess module
  • using Win32 API's CreateProcessA in a custom C++ application.
• This bug is introduced by .Net 7 SDK. I confirmed that by uninstalling the .Net 7.0.102 SDK and getting back to .Net 6.0.113 SDK the bug described above does not occure anymore.
• My dotnet --info:

.NET SDK:
 Version:   7.0.102
 Commit:    4bbdd14480

Runtime Environment:
 OS Name:     Windows
 OS Version:  10.0.19045
 OS Platform: Windows
 RID:         win10-x64
 Base Path:   C:\Program Files\dotnet\sdk\7.0.102\

Host:
  Version:      7.0.2
  Architecture: x64
  Commit:       d037e070eb

.NET SDKs installed:
  3.1.426 [C:\Program Files\dotnet\sdk]
  5.0.102 [C:\Program Files\dotnet\sdk]
  5.0.303 [C:\Program Files\dotnet\sdk]
  5.0.408 [C:\Program Files\dotnet\sdk]
  5.0.416 [C:\Program Files\dotnet\sdk]
  7.0.100 [C:\Program Files\dotnet\sdk]
  6.0.112 [C:\Program Files\dotnet\sdk]
  6.0.113 [C:\Program Files\dotnet\sdk]
  8.0.102 [C:\Program Files\dotnet\sdk]

.NET runtimes installed:
  Microsoft.AspNetCore.All 2.1.30 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
  Microsoft.AspNetCore.App 2.1.30 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 3.1.32 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 5.0.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 5.0.9 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 5.0.17 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 6.0.0 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 6.0.12 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 6.0.13 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.AspNetCore.App 7.0.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
  Microsoft.NETCore.App 2.1.30 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 3.1.32 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 5.0.2 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 5.0.9 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 5.0.10 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 5.0.17 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 6.0.0 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 6.0.12 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 6.0.13 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.NETCore.App 7.0.2 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
  Microsoft.WindowsDesktop.App 3.1.32 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 5.0.2 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 5.0.9 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 5.0.10 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 5.0.17 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 6.0.0 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 6.0.12 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 6.0.13 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
  Microsoft.WindowsDesktop.App 7.0.2 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

Other architectures found:
  arm64 [C:\Program Files\dotnet]
    registered at [HKLM\SOFTWARE\dotnet\Setup\InstalledVersions\arm64\InstallLocation]
  x86   [C:\Program Files (x86)\dotnet]
    registered at [HKLM\SOFTWARE\dotnet\Setup\InstalledVersions\x86\InstallLocation]

Environment variables:
  Not set

global.json file:
  Not found

Learn more:
  https://aka.ms/dotnet/info

Download .NET:
  https://aka.ms/dotnet/download

[dotnet-issue-labeler]

I couldn't figure out the best area label to add to this issue. If you have write-permissions please help me learn by adding exactly one area label.

[nagilson]

This should be fixed in 8.0 preview 3 and 7.0.300 by #30963. Thanks and let us know if there are any issues. You could try it on main now as well.