Массово убрать из файлов данные начиная N строки и до конца файла

@echo off
set "dir=c:\12312"
for %%i in ("%dir%\*.html") do >.tmp more +45 "%%i"& >nul move .tmp "%%i"& echo %%~nxi
exit/b

@echo off
Setlocal EnableDelayedExpansion
chcp 1251>nul
set /p file=Введите имя файла-
set /p m=Введите M-
set /p n=Введите N-
chcp 866>nul
 
Set /A m-=1, n-=1
For /F "delims=" %%A in ('more +%m% ^<"%file%"') do (
  echo %%A
  if !m!==!n! (>nul pause& goto :eof)
  Set /A m+=1
)

@echo off
set nsd=5
<"file.txt">+ find /v /c ""& <+ set/p strs=& set/a strr=strs-nsd
<"file.txt">+ (sort/+2147483647|more +%strr%|sort/+2147483647|findstr/vrc:"^$")& move+ "file.txt"
exit

@echo off
setlocal enabledelayedexpansion
set nd=3& set kd=5
for /l %%a in (%nd%,1,%kd%) do set "ns=!ns! /c:"^\[%%a\]""
<"file.txt">$ (for /f "tokens=2 delims=[]" %%a in ('find /n /v ""^|findstr/rv%ns%') do echo %%a)& move $ "file.txt"
exit

@echo off
set nsd=9
set "dir=c:\12312"
for %%i in ("%dir%\*.txt") do (
set file=%%i
<"%file%">+ find /v /c ""& <+ set/p strs=& set/a strr=strs-nsd
<"%file%">+ (sort/+2147483647|more +%strr%|sort/+2147483647|findstr/vrc:"^$")& move+ "%file%"
)

for %x in (*.html) do @vim +10,$d +x "%x"

@echo off
set "d=C:\Papka"
set nsd=5
for /f "delims=" %%a in ('dir /a-d/b "%d%\*.*"') do call :pf "%%a"
pause& exit
 
:pf
 <"%~1">+ find /v /c ""& <+ set/p strs=& set/a strr=strs-nsd
 <"%~1">+ (sort/+2147483647|more +%strr%|sort/+2147483647|findstr/vrc:"^$")& move+ "%~1"
exit /b