how to add line no. to each line

[emily_3]

Can anyone tell me.
How to add the line number to each line of a file? For example, i want to convert file1 to file2. Is there any command or have to write a script?

#vi file1
aaaaa
bbbbb
ccccc

#vi file2
1;aaaaa
2;bbbbb
3;ccccc
Thanks.
Regards.

[Ermin Borovac · Accepted solution]

Here is one liner in perl.

$ perl -p -e 's/^/$.;/' file1 > file2

[Rajeev Shukla]

Here, try with sed

sed = |sed 'N; s/\n/\;/'

Cheers
Rajeev

[A. Clay Stephenson]

Even easier and yes, there is a command. Use the nl command and specify a separator:

nl -s ';' file1 > file2

Man nl for details.

[Hein van den Heuvel]

Cool Clay! I never knew that 'nl' command whereas I have it on a big sticker on the back of my car!

[(nl) - being the country 'plate' for the NetherLands]

If you have other things to do in the conversion/processing then an other weapon of choice might be awk:

awk '{print NR ";" $0}' file1 > file2


Hein.

[emily_3]

Thanks all of your contribution, i will try in different ways.

[Sanjay Kumar Suri]

If the purpose is to view lines number along with each line, then it can be done in vi itself by the following

Esc
:nu



sks

[H.Merijn Brand (procura]

nl is a strange command, since, imho, it works counterintuitive, because it numbers by default only non-blank lines. In fact, 'nl' never does what I want, and I always use 'pr' instead

I miss, next to nl, the obvious 'pr' command in the mentioned list

# pr -t -n\;4 -w9999 file

# nl -s\; -ba -n file

are almost the same. Please check if nl did not add empty lines on page breaks.

The other solutions are much better, since they number all lines, don't add formatting to the page numbers, and just do what you want

# perl -pe's/^/$.;/' file

# awk '{print NR ";" $0}' file

# sed = file | sed 'N; s/\n/\;/'

I don't like the sed command, because it adds and removes lines, but it works evenly well

Enjoy, Have FUN! H.Merijn