Batch: Wert aus Zeile herausfiltern und dann Bytes in Gigabytes umrechnen

@echo off & setlocal
for /f "tokens=3" %%i in ('dir /-c D:') do set "B=%%i"  
set "GB=%B:~,-9%"  
if not defined GB (
    echo weniger als 1 GB frei
) else (
    echo mindestens %GB% GB frei
)

@echo off &setlocal

set "line=12 Dir(s) 37.184.610.304 bytes free"  
for /f "tokens=3" %%i in ("%line:.=%") do call :B2GiB %%i  
echo %errorlevel:~0,-2%,%errorlevel:~-2%
pause

goto :eof

:B2GiB
setlocal EnableDelayedExpansion
set "B=%~1"  
set "highPart=%B:~0,-6%"  
set "lowPart=%B:~-6%"  
set /a "KB = highPart / 1024 * 1000000, borrow = highPart %% 1024"  
if %borrow% gtr 0 (
  set "lowPart=%borrow%%lowPart%""  
) else (
  for /l %%a in (1,1,5) do if "!lowPart:~0,1!" equ "0" set "lowPart=!lowPart:~1!"  
)
set /a "KB += lowPart / 1024, GB = KB / 1048576, HH = KB %% 1048576 * 100 / 1048576"  
if %HH% lss 10 set "HH=0%HH%"  
endlocal&exit /b %GB%%HH%

<"%HOSTNAME%.txt" set /p "line="