How to read contents of a file from a given line number upto line number again specified by user


 
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# 1  
How to read contents of a file from a given line number upto line number again specified by user

Hello Everyone.

I am trying to display contains of a file from a specific line to a specific line(let say, from line number 3 to line number 5). For this I got the shell script as shown below:

Code:
if [ $# -eq 3 ]; then
        if [ -e $3 ]; then
            tail +$1 $3 | head -n $2
         else
            echo "$0: Error opening file $3"
            exit 2
        fi
else
        echo "Missing arguments!"
fi

Problem with this code is that it always returns lines from the bottom of the file. I even exchanged the commands head and tail, but of no use. While compiling the above code it shows the following:

Code:
tail: cannot open `+3' for reading: No such file or directory
==> /home/chandran/JONAS/LoveSick <==
It's every day, it's every night
O-oh, call the the doctor
I'm love sick

Can anyone please help me out with the solution.

Thank you.
# 2  
Code:
sed -n '3,5p' filename

These 2 Users Gave Thanks to jim mcnamara For This Post:
# 3  
Just use sed:

Code:
% min=3 max=5
% sed -n $min,${max}p infile

This User Gave Thanks to radoulov For This Post:
# 4  
how to get the solution using command line arguments?

Thank you all for the reply.

I am passing the parameters as command line arguments. In that case how do I get the desired result?

Thank you.
# 5  
Code:
% cat display_range.sh 
#!/bin/sh

sed -n "$1,${2}p" "$3"
% chmod u+x display_range.sh 
% print -l {1..10} > infile
% cat infile 
1
2
3
4
5
6
7
8
9
10
% ./display_range.sh 3 7 infile 
3
4
5
6
7

This User Gave Thanks to radoulov For This Post:
# 6  
Thank you..

I got it..

---------- Post updated at 04:44 PM ---------- Previous update was at 04:42 PM ----------

Thank you people, I finally got the solution after all your help.

The code should be like this:

Code:
if [ $# -eq 3 ]; then
        if [ -e $3 ]; then
             sed -n "$1, ${2}p" "$3"
                # tail +$1 $3 | head -n $2
         else
            echo "$0: Error opening file $3"
            exit 2
        fi
else
        echo "Missing arguments!"
fi

It works.
I thank you all once again.

Regards
G Ravi Chandran
 

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