Assign Line Numbers to each line of the file

Shell Programming and Scripting
1

Hi! I'm trying to assign line numbers to each line of the file
for example consider the following..
The contents of the input file are

hello how are you?
I'm fine.
How about you?

I'm trying to get the following output..

1 hello how are you?
2 I'm fine.
3 How about you?

Note:The number has to be followed by a space not a tab..

Any idea of how to do it??
Thanks in advance..

2

Try

awk '{print NR" "$0}' input_file
3 
 
perl -lne 'print "$. $_" input
4

...or, the same in sed:

sed 's/^/= /' /path/to/infile > /path/to/outfile

I hope this helps.

bakunin

5 
cat -n filename
6

@itkamaraj
The separator in "cat -v" is a tab character.

7 
$ nl -nln -s\   infile

If you need to reduce the default numwidth, use the -w option:

$ nl -nln -s\  -w2  infile
1  hello how are you?
2  I'm fine.
3  How about you?
8

i didnt notice the note section

Note:The number has to be followed by a space not a tab..

while read line ; do count=`expr $count + 1`; echo -n "$count "; echo $line; done < filename

while read line ; do count=`echo "$count + 1"|bc`; echo -n "$count "; echo $line; done < filename
9

Thank you for all your replies! :slight_smile: