Get WSL's rootfs directory and home directory of the default user

wslenv.bat

@echo off

rem Get the default distribution
for /f "tokens=3" %%d in ('reg query HKCU\Software\Microsoft\Windows\CurrentVersion\Lxss /v DefaultDistribution') do set DIST=%%d

rem Get distribution name, rootfs directory, and uid
for /f "tokens=3" %%n in ('reg query HKCU\Software\Microsoft\Windows\CurrentVersion\Lxss\%DIST% /v DistributionName') do set DIST_NAME=%%n
for /f "tokens=3" %%p in ('reg query HKCU\Software\Microsoft\Windows\CurrentVersion\Lxss\%DIST% /v BasePath') do set ROOTFS=%%p\rootfs
for /f "tokens=3" %%u in ('reg query HKCU\Software\Microsoft\Windows\CurrentVersion\Lxss\%DIST% /v DefaultUid') do set /a UID=%%u

rem username and home directory from /etc/passwd
for /f "tokens=1 delims=:" %%u in ('findstr /R ":x:%UID%:%UID%:,,," %ROOTFS%\etc\passwd') do set USERNAME=%%u
for /f "tokens=6 delims=:" %%u in ('findstr /R ":x:%UID%:%UID%:,,," %ROOTFS%\etc\passwd') do set HOMEUNIX=%%u

rem Convert Linux path to Windows path
set HOME=%ROOTFS%%HOMEUNIX:/=\%
echo Dist.    : %DIST_NAME%
echo Def. User: %USERNAME%
echo Home(Lin): %HOMEUNIX%
echo Home(Win): %HOME%