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up vote 10 down vote favorite

How can I append a line number and tab to the beginning of each line of a text file?

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What I'm wondering is how you'd do it on Windows... – itsadok Jul 21 '09 at 17:37
1  
Should this be on stackoverflow? For superuser the answer is Notepad & lots of patience. – kokos Jul 21 '09 at 22:10
So, do you want to prepend or append. Your title and body texts are different ;) – sirlancelot Jul 22 '09 at 23:52
I guess I want to append to the beginning, "prepend" being only a word to hackers. – Richard Hoskins Jul 23 '09 at 0:15

8 Answers

up vote 13 down vote accepted 
awk '{printf "%d\t%s\n", NR, $0}' < filename
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1  
Awksome. Thnx. – Richard Hoskins Jul 21 '09 at 17:29
2  
Or awk '{print NR, "\t", $0}'. – jtbandes Jul 23 '09 at 1:18
answer below, with nl command line, is a much simpler solution. – Daniel Ribeiro Oct 8 '12 at 20:38
up vote 9 down vote

The nl command should do this, but it adds space before the line number too. It's part of Linux coreutils.

nl lines.txt
 1  $bkWTN
 2  $cV8$.
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Actually, you can tell nl to omit the space before the number. Just use the -w1 option to tell it the minimum width for a number is 1. – cjm Feb 26 at 23:09
up vote 4 down vote 
sed = test.txt | sed 'N;s/\n/\t/'

The command "sed =" will print the line number followed by a carriage return and then the next line.

The expression "N;s/\n/\t/" will take each line, get the next line (ie line number and the line), and replace the carriage return with a tab.

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Prints a "t" with no tab with my version of sed: 8t I saw the best minds of my generation destroyed by 9t madness, starving hysterical naked, – Richard Hoskins Jul 21 '09 at 16:49
up vote 3 down vote 
cat -n <yourfile> | perl -pe "s/^\s*(\d+)\s+/\1\t/"

cat -n adds linenumbers as " 123 linecontents" and that regexp modifies it to "linenumberTABlinecontents"

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up vote 2 down vote 
perl -pe "s/^/$.\t$_/" file.txt

or

perl -ne "print qq($.\t$_)" file.txt
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up vote 1 down vote

Ok, since we are collecting ways to do this,

 grep -n . file.txt | sed 's/\(^[0-9]*\):/\1    /g'
 # this is a tab with Ctrl-V + Tab  =====>  ----
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Now I see this. OK, delete my own post. What? You say that SU doesn't let you delete your own post? – Kevin M Jul 23 '09 at 0:42
grep + sed == awk – Tadeusz A. Kadłubowski Jul 23 '09 at 12:50
up vote 1 down vote 
sed file.txt -e 's/^/\t/' | cat -n | sed -e 's/^\t//'

or for some non-GNU seds:

cat file.txt | sed -e 's/^/\\t/' | cat -n | sed -e 's/^\\t//'
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Prints a "t" with no tab with my version of sed. – Richard Hoskins Jul 21 '09 at 16:54
Edited to double-escape; try it like that. – chaos Jul 21 '09 at 17:18
If all else fails, just hit tab. :) (Or ^V tab if your shell gives you trouble with that.) – chaos Jul 21 '09 at 17:19
sed: 1: "test.txt": undefined label 'est.txt' – Richard Hoskins Jul 21 '09 at 17:24
'cat test.txt | sed -e 's/^/\\t/' | cat -n' prints (tab)number(space)\t(line) – Richard Hoskins Jul 21 '09 at 17:25
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up vote 0 down vote

How about

cat -n somefile.txt

?

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1  
No tab. (Comments needing 15 chars is a stupid requirement.) – Richard Hoskins Jul 21 '09 at 16:42
This produces tabs on my system. cat (GNU coreutils) 6.10. – innaM Jul 21 '09 at 16:50
On my system, it adds (tab)number(space)line. BSD Utils. – Richard Hoskins Jul 21 '09 at 16:59

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