binfmt.cpp: CreateNtProcessConfigureConsole: tcgetpgrp failed: Error is logged even though it is not an error

[trallnag]

Windows Version

10.0.22621.5472

WSL Version

2.5.9.0

Are you using WSL 1 or WSL 2?

• WSL 2
• WSL 1

Kernel Version

6.6.87.2

Distro Version

Ubuntu 24.04

Other Software

Nothing of relevance.

Repro Steps

Within the distribution in a Bash or Zsh shell, execute the following:

sudo setsid --fork --wait "/mnt/c/Program Files/PowerShell/7/pwsh.exe" -NoLogo -NonInteractive -Command "Get-Date" 2>&1

Expected Behavior

Output just includes the date.

The relevant code is:

WSL/src/linux/init/binfmt.cpp

Lines 683 to 693 in 902848b

	auto processGroup = tcgetpgrp(0);
	if (processGroup < 0)
	{
	LOG_STDERR("tcgetpgrp failed");
	return;
	}
	if (processGroup != getpgrp())
	{
	return;
	}

I wonder why in the case of tcgetpgrp the error is logged but if getpgrp has a problem no error is logged. Maybe the log statement was once added for debugging purposes?

I came across this when setting up a scheduled monitoring task in WSL using Monit that triggers Powershell to send a notification to the desktop. It does so without a TTY.

Actual Behavior

Output includes error from binfmt and date.

tcgetpgrp failed: Not a tty
Montag, 23. Juni 2025 12:00:47

Diagnostic Logs

WslLogs-2025-06-23_12-10-43.zip

[github-actions]

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Diagnostic information

Issue was edited and new log file was found: https://github.com/user-attachments/files/20862992/WslLogs-2025-06-23_12-10-43.zip
.wslconfig found
Detected appx version: 2.5.9.0

[trallnag]

this has been fixed in #13176