Deleting last n lines from file using batch file

Question

How to delete last n lines from file using batch script

I don\'t have any idea about batch files, I am writing batch file for the first time.

How should I wr

Answer 1

This the complete script for remove last N line

• count the total line
• set Line = Line - N , remain just processing lines number

@echo OFF
setlocal EnableDelayedExpansion

set LINES=0
for /f "delims==" %%I in (infile.txt) do (
    set /a LINES=LINES+1    
)

echo Total Lines : %LINES%
echo.

:: n = 5 , last 5 line will ignore 
set /a LINES=LINES-5

call:PrintFirstNLine > output.txt

goto EOF

:PrintFirstNLine
set cur=0
for /f "delims==" %%I in (infile.txt) do (      
    echo %%I        
    ::echo !cur! : %%I      
    set /a cur=cur+1    
    if "!cur!"=="%LINES%" goto EOF
) 

:EOF 

exit /b

Here call:PrintFirstNLine > output.txt will give the output in an external file name as output.txt

Output for sample Input

<Project_Name>      
<CBA_Notifier>      
    <Common>        
    <File>D:\CBA\CBA_Notifier\Project_Name\IPS-Util.jar</File>      
    <File>D:\CBA\CBA_Notifier\Project_Name\Notifier.bat</File>      
    <File>D:\CBA\CBA_Notifier\Project_Name\Notifier.xml</File>      
    <File>D:\CBA\CBA_Notifier\Project_Name\Notifier.jar</File>              
    </Common>       
    <Project_Name>      
        <File>D:\CBA\CBA_Notifier\IPS-Util.bat</File>   

remove last 5 line

Update

:PrintFirstNLine
set cur=0
for /F "tokens=1* delims=]" %%I in ('type "infile.txt" ^| find /V /N ""') do (
   if "%%J"=="" (echo.) else (
        echo.%%J
        set /a cur=cur+1    
        )  

   if "!cur!"=="%LINES%" goto EOF
)

Answer 2

This script will takes 1 arguement, the file to be trunkated, creates a temporary file and then replaces the original file with the shorter one.

@echo off
setlocal enabledelayedexpansion
set count=
for /f %%x in ('type %1 ^| find /c /v ""') do set /a lines=%%x-5
copy /y nul %tmp%\tmp.zzz > nul
for /f "tokens=*" %%x in ('type %1 ^| find /v ""') do (
  set /a count=count+1
  if !count! leq %lines% echo %%x>>%tmp%\tmp.zzz
)
move /y %tmp%\tmp.zzz %1 > nul

If the original file is 5 or less lines, the main output routine will noT create a file. To combat this, I use the copy /y null to create a zero byte file.

If you would rather not have an empty file, just remove the copy /y nul line, and replace it with the following line:

if %lines% leq 0 del %1

You should use one method or the other, otherwise source files with 5 or less lines will remain untouched. (Neither replaced or deleted.)

Answer 3

to delete last lines from your file,

1 copy starting lines that are needed from file like from- e:\original.txt 2 paste them in new file like- e:\new\newfile1.txt

code is thanks to the person giving me this code: remember all may be done if you have motive and even blood hb =6. but help of nature is required always as you are a part of it

@echo off & setLocal enableDELAYedeXpansion set N= for /f "tokens=* delims= " %%a in (e:\4.txt) do ( set /a N+=1 if !N! gtr 264 goto :did

e:\new4.txt echo.%%a ) :did

if you have 800 files then use excel to make code for 800 and then copy it to notepad and using Ctrl+h replace space with no space. then rename file as haha.bat . run in folder with files numbered 1.txt 2.txt 3.txt etc. any enquirers welcome Erkamaldev@gmail.com " Long Live Bharata"

Answer 4

A slow method with less coding:

set input=file.txt
set remove=7

for /f "delims=" %i in ('find /c /v "" ^< "%cd%\%input%"') do set lines=%i
set /a lines-=remove
for /l %i in (1,1,!lines!) do findstr /n . log.txt | findstr /b %i:

May be redirected to a file.
Each line is prefixed with the line number; may be removed with extra coding.
A faster version with /g flag in my answer at:
How to split large text file in windows?

Tested in Win 10 CMD, on 577KB file, 7669 lines.