windows - Increment a number with leading zeros by a batch file -

getting trouble incrementing number zeros in front.

it fail after 0008 telling me filename exist or file not found. odd.

here script:

@echo off  copy nul %tmp%\filename.tmp  /f "tokens=2 delims=-." %%a in (    'dir /b "%tmp%\filename*.tmp" ^|sort /r ^|findstr /r [0-9]' ) (       set "num=%%a"       goto :done )  ren %tmp%\filename.tmp  filename-0001.tmp exit /b 0  :done echo highest number found %num% set /a num+=1 set incr=0000%num%  ren %tmp%\filename.tmp  filename-%incr:~-4%.tmp  dir /b "%tmp%\filename*.tmp" |sort /r 

thus simplifying problem:

@echo off  set "num=008" echo num: %num% set /a num=num+1 echo num: %num%  echo let's try syntax set "num=008" echo num: %num% set /a num+=1 echo num: %num% 

output:

num: 008 num: 1 let's try syntax num: 008 num: 1 

another way add preceding 1 (so it's not interpreted octal), increment, trim away 1.

the largest number limited cmd's set /a command.

@echo off set "num=008" echo num: %num% set "num=1%num%" echo num: %num% set /a num=num+1 echo num: %num% set  num=%num:~1% echo num: %num% pause