Код:
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@Echo Off
cls
Set "FileIn=Z:\Box_In\File.txt"
Set "FileOut=Z:\Box_In\FileString.txt
Call :WriteCount "%FileIn%" "%FileOut%" "%~nx0"
more "%FileOut%"
Pause
GoTo :Eof
:WriteCount
Set "Counter=%~dp2%~nx1.%~3.log"
If Not Exist "%Counter%" (
>"%Counter%" (Echo 1)
FOR /F "usebackq delims=" %%s IN (%1) DO (>"%FileOut%" (Echo %%s) &Exit /B 0)
Exit /B 2
)
3<"%Counter%" (Set /P N=<&3)
Set /A NN=%N%+1
FOR /F "usebackq skip=%N% delims=" %%s IN (%1) DO (>"%Counter%" (Echo %NN%) &>"%FileOut%" (Echo %%s) &Exit /B 0)
Del "%Counter%"
GoTo :WriteCount
GoTo :Eof
В исходном файле не должно быть пустых строк