Batch Snippet: Generic Backup

REM Generic backup script
REM https://stackoverflow.com/questions/11280077/batch-script-to-make-backup-folder-only-new-and-modified-files

@echo off
REM get start time
for /f "tokens=2 delims==" %%a in ('wmic OS Get localdatetime /value') do set "dt=%%a"
set "YY=%dt:~2,2%" & set "YYYY=%dt:~0,4%" & set "MM=%dt:~4,2%" & set "DD=%dt:~6,2%"
set "HH=%dt:~8,2%" & set "Min=%dt:~10,2%" & set "Sec=%dt:~12,2%"

REM set "datestamp=%YYYY%%MM%%DD%" & set "timestamp=%HH%%Min%%Sec%"
set "fullstamp=%YYYY%-%MM%-%DD%_%HH%-%Min%-%Sec%"
set "logtimestamp=%YYYY%.%MM%.%DD% %HH%:%Min%:%Sec%"

REM actual copy
set source=%1
set destination=%2

REM create the exclusion list
set exclusion=%3
set exclusion=%exclusion:"=%
(for %%i in (%exclusion%) do echo %%i) > exclusion.txt

REM set the file name for the logging data
set log=log-%fullstamp%.txt

REM start the backup process
echo // started backup at %logtimestamp% > %log%
echo // from %~f1 to %~f2\ >> %log%

echo ---- >> %log%
xcopy %source% %destination% /S /E /C /D /H /R /Y /V /I /EXCLUDE:exclusion.txt >> %log%
echo ---- >> %log%
del /f exclusion.txt

REM get finish time
for /f "tokens=2 delims==" %%a in ('wmic OS Get localdatetime /value') do set "dt=%%a"
set "YY=%dt:~2,2%" & set "YYYY=%dt:~0,4%" & set "MM=%dt:~4,2%" & set "DD=%dt:~6,2%"
set "HH=%dt:~8,2%" & set "Min=%dt:~10,2%" & set "Sec=%dt:~12,2%"
set "logtimestamp=%YYYY%.%MM%.%DD% %HH%:%Min%:%Sec%"

echo // finished backup at %logtimestamp% >> %log%

REM move the logging
if not exist "%destination%\.backup_log" mkdir %destination%\.backup_log
move %log% %destination%\.backup_log