@echo off
setlocal enableextensions
call :getNextFilename "filename*.txt" nextFilename
echo %nextFilename%
echo test > "%nextFilename%"
call :getNextFilename "%cd%\filename*.txt" nextFilename
echo %nextFilename%
echo test > "%nextFilename%"
endlocal
exit /b
:getNextFilename whatToSearch returnVariable
setlocal enableextensions enabledelayedexpansion
for /f %%a in ("$\%~1"
) do for /f "tokens=1,* delims=*" %%b in ("%%~nxa"
) do ( set "left=%%b" & set "right=%%c" )
set "max=0"
for %%a in ("%~1"
) do for /f "tokens=1 delims=%left%%right% " %%b in ("%%~nxa"
) do for /f "tokens=* delims=0 " %%c in ("0%%~b"
) do if %%~c geq !max! set /a "max=%%c+1"
endlocal & set "%~2=%~dp1%left%%max%%right%" & exit /b
This should find the next file in sequence independently of the existence of holes in the numeration of the files. A path can be included or omitted. The *
will be used as the placeholder for the numeration. BUT this will not work if files or included paths have "problematic" characters.
If the date/time of creation of the file can be considered, then this version can be optimized as
:getNextFilename whatToSearch returnVariable
setlocal enableextensions disabledelayedexpansion
for /f %%a in ("$\%~1"
) do for /f "tokens=1,* delims=*?" %%b in ("%%~nxa"
) do ( set "left=%%b" & set "right=%%c" )
set "max=0"
for /f "delims=" %%a in ('dir /tc /o-d /b "%~1" 2^>nul'
) do for /f "tokens=1 delims=%left%%right% " %%b in ("%%~nxa"
) do for /f "tokens=* delims=0 " %%c in ("0%%~b"
) do set /a "max=%%c+1" & goto done
:done
endlocal & set "%~2=%~dp1%left%%max%%right%" & exit /b
that will take the latest created instance of the file set.