How to get just the first line of a text file written into a new text file using a batch file? - batch-file

Question

Okay I have several lines in a text file. I want to get the first line and save it in another file. For example this is the text file:
put returns between paragraphs
for linebreak add 2 spaces at end
for linebreak add 2 spaces at end2
for linebreak add 2 spaces at end3
I want put returns between paragraphs to be saved into another file.
I used
for /f "tokens=" %%A in ('findstr /r "^[0-9][0-9]*$" <"C:\Users\Sherlock\Desktop\AbcImport\123.txt"') do echo 123>>1234.txt
pause
But it doesn't work at all.
How to get just the first line of a text file written into a new text file using a batch file?

Answer 1

Option 1 - SET /P : This is the simplest and fastest pure batch solution, provided the line does not exceed 1021 bytes, and it does not end with control characters that must be preserved. The size of the file does not matter - it will always read and write the first line very quickly.
#echo off
setlocal enableDelayedExpansion
set "ln="
<"input.txt" set /p "ln="
>"output.txt" (echo(!ln!)
Option 2 - FOR /F : This will work with lines up to ~8191 bytes long, but it can be slow if the file is really large because the FOR /F loop must read the entire file before it processes the first line. This solution is basically the same as the Mofi answer, except it disables the EOL option, so it never ignores the first line, regardless what the first character is. It does have a limitation that it will skip empty lines, so technically it does not give the correct result if the first line is empty:
#echo off
for /f usebackq^ delims^=^ eol^= %%A in ("input.txt") do echo(%%A>"output.txt"&goto :break
:break
There is a way to preserve the first line if it is empty using pure batch, but I would not bother. I would move on to ...
Option 3 - JREPL.BAT, or some other non-batch solution : Batch is quite poor at manipulating text files. You are much better off using some other scripting language like VBScript, JScript, or Powershell. Or a Windows port of any number of unix utilities.
I would use JREPL.BAT - a hybrid JScrpit/batch regular expression text processing utility that runs natively on any Windows machine from XP onward. It is way overkill for such a simple task, but it is an extremely handy, powerful, and efficient tool to have in your arsenal. Once you have it, then it can be used for many text processing tasks. Full documentation is embedded within the script.
jrepl "^.*" "$&" /jendln "quit=true" /f "input.txt" /o "output.txt"
Use CALL JREPL if you put the command within a batch script.

Answer 2

Here is the batch code to write just first non blank/empty line of a text file into another text file.
#echo off
for /F "usebackq delims=" %%I in ("InputTextFile.txt") do (
echo %%I>"OutputTextFile.txt"
goto ContinueAfterLoop
)
:ContinueAfterLoop
InputTextFile.txt is the file in current directory containing the first line to copy.
OutputTextFile.txt is the file created in current directory with first line from input file copied into this output file.
The command GOTO is used to exit the loop after first line is processed and continue the batch file below the loop.
For understanding the used commands and how they work, open a command prompt window, execute there the following commands, and read entirely all help pages displayed for each command very carefully.
echo /?
for /?
goto /?
Read also the Microsoft article about Using Command Redirection Operators.

Answer 3

You can use use this command:
SetLocal EnableDelayedExpansion
for /f "tokens=* delims=;" %%m in ("C:\Users\Sherlock\Desktop\AbcImport\123.txt") do (
set /p FirstLine=<%%m
echo !FirstLine!>>1234.txt
)
and for multiple file:
SetLocal EnableDelayedExpansion
for %%a in ("*") do (
for /f "tokens=* delims=;" %%m in ("%%a") do (
set /p FirstLine=<%%m
echo !FirstLine!>>1234.txt
)
)

Answer 4

rem Get the first line of a text file:
set /P "line=" < "C:\Users\Sherlock\Desktop\AbcImport\123.txt"
rem Write it into a new text file:
echo %line%> 1234.txt