Echo the nth line from a text file where 'n' is a command line argument
I have a simple text file with numbers like:
12345
45678
34567
89101
I need a batch that will return the n
th line from this file. n
should be taken from a command line argument.
I am very new to开发者_开发知识库 batch scripting so Thanks in advance for any help on this.
To get the file from the nth line you could use more +n (For line1 is n=0).
To split the rest of the file you could use a FOR /F
loop.
This works even, if there are empty lines before the nth line.
It could be necessary to set the EOL to an unused character or to linefeed (default is ;
)
set "lineNr=%1"
set /a lineNr-=1
for /f "usebackq delims=" %%a in (`more +%lineNr% text.txt`) DO (
echo %%a
goto :leave
)
:leave
You can use batch file extension.
token.bat
@echo off
setlocal ENABLEDELAYEDEXPANSION
set l=%1
set c=0
for /f "delims=" %%1 in ('type foo.txt') do (
set /a c+=1 && if "!c!" equ "%l%" echo %%1%
)
If you have a file like following,
foo.txt
AAAA
BBBB
CCCC
DDDD
And specify line number like following
token 3
You'll get
CCCC
You could use FOR /F
with the skip
parameter:
@ECHO OFF
SET skip=%1
SET /A skip-=1
IF %skip% LSS 0 GOTO out
IF %skip% GTR 0 SET params="skip=%skip%"
FOR /F %params% %%L IN (filename) DO (SET "line=%%L"& GOTO out)
:out
ECHO %line%
The skip
parameter means the FOR /F
loop must skip the specified number of lines at the beginning. The parameter is only applied if you specify a line number greater than 1. If you specify a number less than one or a non-number, the script outputs an empty string.
+1 for Jeb's solution... I did not realize you could use the more command to skip lines like that!
Here is an alternate method that I use for getting a specific line from a file (or from the multi-line output of another program):
@echo off
for /f "tokens=1* delims=:" %%a in ('findstr /n .* "C:\SomeFile.txt"') do (
if "%%a" equ "%1" echo.%%b
)
I use findstr /n .* "Path\FileName.ext" to add line numbers, and to ensure no empty lines are skipped by the for loop.
I then set "tokens=1* delims=:" to separate the line numbers from the line content.
Finally, I compare the current line number (%%a) with the line specified by the %1 parameter, and echo the line contents (%%b) on a match.
To Find Nth to Mth Character In Line No. L --- Example For Finding Label
@echo off
REM Next line = Set command value to a file OR Just Choose Your File By Skipping The Line
vol E: > %temp%\justtmp.txt
REM Vol E: = Find Volume Lable Of Drive E
REM Next Line to choose line line no. +0 = line no. 1
for /f "usebackq delims=" %%a in (`more +0 %temp%\justtmp.txt`) DO (set findstringline=%%a& goto :nextstep)
:nextstep
REM Next line to read nth to mth Character here 22th Character to 40th Character
set result=%findstringline:~22,40%
echo %result%
pause
exit /b
Save as find label.cmd
The Result Will Be Your Drive E Label
Enjoy
Based off of Amit's Answer, I made a utility called snip.cmd.
USAGE: snip FILE LINE FIRSTCHARACTER LASTCHARACTER
example:
foo.txt
//
// File Checksum Integrity Verifier version 2.05.
//
77752e4c91ba96dcc6c2bb4bdcdbdec5 c:\users\lapinot\desktop\token.bat
snip foo.txt 3 0 33 will yield 77752e4c91ba96dcc6c2bb4bdcdbdec5
Here is my code for snipe.cmd (you can add snipe to your command line by copying snip.cmd to c:\Windows\System32):
@echo off
:: USAGE
:: snip <file> [Line - Starts at 0] [First Column - Start Count at 0] [Last Colum]
set file=%1
set line=%2
set char1=%3
set char2=%4
for /f "usebackq delims=" %%a in (`more +%line% %file%`) DO (set findstringline=%%a& goto :nextstep)
:nextstep
echo echo %%findstringline:^~%char1%,%char2%%% > %temp%\result.bat
%temp%\result.bat
del %temp%\result.bat
:EOF
exit /b
echo "enter the line number.."; read i; awk 'NR==$i' <file_name>;
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