Nesting for loop in batch file

Question

I want to nest a for loop inside a batch file to delete carriage return. I tried it like you can see below but it does not work.

@echo off
setLocal EnableDelayedExpansion

for /f "tokens=* delims= " %%a in (Listfile.txt) do (
    set /a N+=1
    set v!N!=%%a
)

for /l %%i in (1, 1, %N%) do (
    echo !v%%i!
    for /r "tokens=* delims=" %%i in (windows.cpp) do (
        echo %%i >> Linux11.cpp
    )
)
pause

Here I want to check with windows.cpp. If its working I like to change windows .cpp with !v%%i!

Answer 1

You cannot do this in a batch file. You have no way of addressing or writing arbitrary characters. Every tool on Windows normally makes sure to output Windows line breaks (i.e. CR+LF). Some can read Unix-style line breaks just fine, which is why you can easily convert from them. But to them isn't possible.

Also as a word of caution: Source code files often contain blank lines (at least mine do) that are for readability. for /f skips empty lines which is why you're mangling the files for your human readers there. Please don't do that.

As for your question: When nesting two loops you have to make sure that they don't use the same loop variable. Show me a language where code like you wrote actually works.

Something like

for /l %%i in (1, 1, %N%) do ( 
  echo !v%%i! 
  for /f "tokens=* delims=" %%l in ("!v%%i!") do (   
    rem do whatever you want to do with the lines      )
)

should probably work better (you missed the final closing parenthesis as well). Thing to remember: If you want to use a certain variable instead of a fixed file name it surely helps replacing that fixed file name by that variable.

Answer 2

It would be probably easiest to use some unix2dos/dos2unix converter to do that or some win32 flavor of sed.