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"How to read lines from a file"

Hi,

I want to read lines from a file line-by-line and to display those lines on the terminal.
Can any one please provide a shell script for this.:study:

cat filename | more -1
The "|" is the pipe sysmbol (shift \ on my keyboard).

Hi,

I'm not sure what you're trying to do, but I'd use sed, e.g.

Quote:

sed -n "${i}p" $file

A longer longer example would be something like

Quote:

#! /bin/bash

file=/etc/fstab
nlines=$(wc -l $file | cut -f1 -d' ')
i=0

while [ $i -le $nlines ]
do
echo "Give me a line number"
read i
sed -n "${i}p" $file
done

echo "Reached end"

Hope this helps :)

Cheers

Quote:

Originally Posted by sharath.bv (Post 3042049)

Hi,

I want to read lines from a file line-by-line and to display those lines on the terminal.
Can any one please provide a shell script for this.:study:

This is obviously just a starting point, so please forgive me for asking.

What are you trying to achieve?

To read each line into a variable you could do:

Code:

#!/bin/bash

cat myfile|while read line

do

  ##perform some checks

  echo $line

done

However, this strips out any leading spaces or tab characters, therefore you may not get what you are after.

To do the same thing in Perl (which doesn't strip out leading spaces or tab characters):

Code:

#!/usr/bin/perl

open(INPUT, "myfile") or die "Could not open input file";



while (<INPUT>) {

  ##perform some checks

  print;

}



close(INPUT);

Thanks all,
i got the answer.........:)

The simplest and most readable way is (IMO):

Code:

while read line

do

  echo $line

done < file