Using wslinfo --env to read Windows environment variables

[marveloo]

PROBLEM
Currently, one of the most practical methods for accessing Windows environment variables in WSL is by listing the required variables in WSLENV on the Windows host. However, this approach presents a challenge, as shell scripts running on WSL cannot modify this configuration on the host. An alternative is to read the output of commands like cmd.exe /C set VARNAME in Linux, but this method is inelegant and unreliable. For example, when using sudo to execute a script, cmd.exe becomes inaccessible, which requires either instructing the user to pass additional environment-related arguments to sudo to access the Windows PATH, or specifying the full path to cmd.exe in the script. Both of these solutions are neither elegant nor reliable.

SOLUTION
I believe that using wslinfo --env would be the most efficient and reliable method for accessing Windows environment variables within shell scripts. For example:

$ wslinfo --env=LOCALAPPDATA
C:\Users\john\AppData\Local

$ wslinfo --env=HOMEDRIVE
C:

Moreover, this command may also support the additional -p and -l flags, similar to their usage with WSLENV. Specifically, the -p flag converts a Windows path into a Linux path, while the -l flag converts a Windows semicolon-delimited path list into a Linux colon-delimited path list. For example:

$ wslinfo --env=LOCALAPPDATA
C:\Users\john\AppData\Local

$ wslinfo --env=LOCALAPPDATA -p
/mnt/c/Users/john/AppData/Local

$ wslinfo --env=PATHLIST
C:\Users\john;C:\Users\mike;C:\Users\rose

$ wslinfo --env=PATHLIST -l
/mnt/c/Users/john:/mnt/c/Users/mike:/mnt/c/Users/rose

[github-actions]

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How to collect WSL logs

Download and execute collect-wsl-logs.ps1 in an administrative powershell prompt:

Invoke-WebRequest -UseBasicParsing "https://raw.githubusercontent.com/microsoft/WSL/master/diagnostics/collect-wsl-logs.ps1" -OutFile collect-wsl-logs.ps1
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.\collect-wsl-logs.ps1

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[marveloo]

/feature

[github-actions]

Diagnostic information

Found '/feature', adding tag 'feature'