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Windows batch command(s) to read first line from text file

Tags:

batch-file

cmd

How can I read the first line from a text file using a Windows batch file? Since the file is large I only want to deal with the first line.

like image 575
Jesse Vogt Avatar asked Sep 24 '08 21:09

Jesse Vogt


People also ask

How do I batch read a text file?

Reading of files in a Batch Script is done via using the FOR loop command to go through each line which is defined in the file that needs to be read. Since there is a no direct command to read text from a file into a variable, the 'for' loop needs to be used to serve this purpose.

What does S do in a batch file?

The Windows command prompt ( cmd.exe ) has an optional /s parameter, which modifies the behavior of /c (run a particular command and then exit) or /k (run a particular command and then show a shell prompt).

What is %% K in batch file?

So %%k refers to the value of the 3rd token, which is what is returned.

What does %% A mean in batch file?

%%a refers to the name of the variable your for loop will write to. Quoted from for /? : FOR %variable IN (set) DO command [command-parameters] %variable Specifies a single letter replaceable parameter. (set) Specifies a set of one or more files. Wildcards may be used.


13 Answers

uh? imo this is much simpler

  set /p texte=< file.txt     echo %texte% 
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Spaceballs Avatar answered Nov 10 '22 02:11

Spaceballs


Here's a general-purpose batch file to print the top n lines from a file like the GNU head utility, instead of just a single line.

@echo off

if [%1] == [] goto usage
if [%2] == [] goto usage

call :print_head %1 %2
goto :eof

REM
REM print_head
REM Prints the first non-blank %1 lines in the file %2.
REM
:print_head
setlocal EnableDelayedExpansion
set /a counter=0

for /f ^"usebackq^ eol^=^

^ delims^=^" %%a in (%2) do (
        if "!counter!"=="%1" goto :eof
        echo %%a
        set /a counter+=1
)

goto :eof

:usage
echo Usage: head.bat COUNT FILENAME

For example:

Z:\>head 1 "test file.c"
; this is line 1

Z:\>head 3 "test file.c"
; this is line 1
    this is line 2
line 3 right here

It does not currently count blank lines. It is also subject to the batch-file line-length restriction of 8 KB.

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indiv Avatar answered Nov 10 '22 03:11

indiv


Uh you guys...

C:\>findstr /n . c:\boot.ini | findstr ^1:

1:[boot loader]

C:\>findstr /n . c:\boot.ini | findstr ^3:

3:default=multi(0)disk(0)rdisk(0)partition(1)\WINNT

C:\>
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Amit Naidu Avatar answered Nov 10 '22 03:11

Amit Naidu


You might give this a try:

@echo off

for /f %%a in (sample.txt) do (
  echo %%a
  exit /b
)

edit Or, say you have four columns of data and want from the 5th row down to the bottom, try this:

@echo off

for /f "skip=4 tokens=1-4" %%a in (junkl.txt) do (
  echo %%a %%b %%c %%d
)
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Ross Fuhrman Avatar answered Nov 10 '22 03:11

Ross Fuhrman


Thanks to thetalkingwalnut with answer Windows batch command(s) to read first line from text file I came up with the following solution:

@echo off
for /f "delims=" %%a in ('type sample.txt') do (
echo %%a
exit /b
)
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Jesse Vogt Avatar answered Nov 10 '22 03:11

Jesse Vogt


Slightly building upon the answers of other people. Now allowing you to specify the file you want to read from and the variable you want the result put into:

@echo off
for /f "delims=" %%x in (%2) do (
set %1=%%x
exit /b
)

This means you can use the above like this (assuming you called it getline.bat)

c:\> dir > test-file
c:\> getline variable test-file
c:\> set variable  
variable= Volume in drive C has no label.
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Ray Hayes Avatar answered Nov 10 '22 04:11

Ray Hayes


powershell Get-Content file.txt -Head 1

This one is much quicker than the other powershell examples above, where the full file is read.

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Ingmar Avatar answered Nov 10 '22 04:11

Ingmar


One liner, useful for stdout redirect with ">":

@for /f %%i in ('type yourfile.txt') do @echo %%i & exit
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PabloG Avatar answered Nov 10 '22 04:11

PabloG


Try this

@echo off
setlocal enableextensions enabledelayedexpansion
set firstLine=1
for /f "delims=" %%i in (yourfilename.txt) do (
    if !firstLine!==1 echo %%i
    set firstLine=0
)
endlocal
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Sarath KS Avatar answered Nov 10 '22 02:11

Sarath KS


To cicle a file (file1.txt, file1[1].txt, file1[2].txt, etc.):

START/WAIT C:\LAERCIO\DELPHI\CICLADOR\dprCiclador.exe C:\LAERCIUM\Ciclavel.txt

rem set/p ciclo=< C:\LAERCIUM\Ciclavel.txt:
set/p ciclo=< C:\LAERCIUM\Ciclavel.txt

rem echo %ciclo%:
echo %ciclo%

And it's running.

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Laercio Avatar answered Nov 10 '22 02:11

Laercio


Another way

setlocal enabledelayedexpansion
@echo off
for /f "delims=" %%i in (filename.txt) do (
if 1==1 (
set first_line=%%i
echo !first_line!
goto :eof
))
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hhay Avatar answered Nov 10 '22 02:11

hhay


The problem with the EXIT /B solutions, when more realistically inside a batch file as just one part of it is the following. There is no subsequent processing within the said batch file after the EXIT /B. Usually there is much more to batches than just the one, limited task.

To counter that problem:

@echo off & setlocal enableextensions enabledelayedexpansion
set myfile_=C:\_D\TEST\My test file.txt
set FirstLine=
for /f "delims=" %%i in ('type "%myfile_%"') do (
  if not defined FirstLine set FirstLine=%%i)
echo FirstLine=%FirstLine%
endlocal & goto :EOF

(However, the so-called poison characters will still be a problem.)

More on the subject of getting a particular line with batch commands:

How do I get the n'th, the first and the last line of a text file?" http://www.netikka.net/tsneti/info/tscmd023.htm

[Added 28-Aug-2012] One can also have:

@echo off & setlocal enableextensions
set myfile_=C:\_D\TEST\My test file.txt
for /f "tokens=* delims=" %%a in (
  'type "%myfile_%"') do (
    set FirstLine=%%a& goto _ExitForLoop)
:_ExitForLoop
echo FirstLine=%FirstLine%
endlocal & goto :EOF
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Timo Salmi Avatar answered Nov 10 '22 04:11

Timo Salmi


Here is a workaround using powershell:

powershell (Get-Content file.txt)[0]

(You can easily read also a range of lines with powershell (Get-Content file.txt)[0..3])

If you need to set a variable inside a batch script as the first line of file.txt you may use:

for /f "usebackq delims=" %%a in (`powershell ^(Get-Content file.txt^)[0]`) do (set "head=%%a")
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mmj Avatar answered Nov 10 '22 02:11

mmj