Read ONLY x lines from a txt file with a windows batch file

Question

How can I read only X lines from a a.txt file?

The file contains all the names of a directory, I would like to read only x lines. X can be a number that can varies from 1 to 99

Answer 1

You'll need to modify this based on your needs, but the script below will loop through the file 'directories.txt', and ECHO the contents of the line until you hit the maximum number of lines set in maxlines.

@ECHO OFF
setlocal enabledelayedexpansion

SET /A maxlines=1
SET /A linecount=0

FOR /F %%A IN (directories.txt) DO ( 
  IF !linecount! GEQ %maxlines% GOTO ExitLoop
  ECHO %%A 
  SET /A linecount+=1
)

:ExitLoop

PAUSE

Answer 2

you can use vbscript. Here's an example

Set objFS = CreateObject("Scripting.FileSystemObject")
Set objArgs = WScript.Arguments
strNum = objArgs(0)
strFile=objArgs(1)
Set objFile = objFS.OpenTextFile(strFile)
Do Until objFile.AtEndOfLine
    If CInt(objFile.Line) > CInt(strNum) Then
      Exit Do  
    End If 
    strLine=objFile.ReadLine
    WScript.Echo strLine    
Loop

save as myscript.vbs and

c:\test> cscript //nologo myscript.vbs 99 file

Or if have the luxury to install tools, you can download sed or gawk for windows . Then on the command line

sed.exe "99q" file
gawk.exe "NR>2{exit}1" file

Answer 3

the command:

set/a linecount+=1 into the FOR loop is not incremented.

If I run the command line set/a linecount+=1 from the command prompt then it works, otherwise from the batch file it doesn't

Answer 4

I wrote it exactly as you did, but the counter doesn't increment itself.

I have seen that the command set /a linecount+=1 doesn't increment itself when is inside a FOR loop, but I haven't found a solution yet.

Answer 5

Ok it works,

it's only that if I want to echo linecount during the for loop i have to use echo !linecount!.

Thank you very much and sorry for the incomprehension