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Query regarding for loop.

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# 1  
Old 07-21-2010
Query regarding for loop.
Filename.txt
Code:
My First Line
My Second Line

::::While Loop:::
Program:
Code:
while read line
do
echo "$line"
done < Filename.txt

output:
Code:
My First Line
My Second Line

Is it possible to use for loop to get the same output.
I have tried executing below code but i get every word of my file being displayed one below above.Is there any way i can modify the for loop code to get the output returned by while loop?

:::For Loop:::
Program:
Code:
for line in $(cat Filename.txt)
do
echo $line
done

output:
Code:
My
First
Line
My
Second
Line

# 2  
Old 07-21-2010
Set your input field separator

Code:
$  IFS=$'\n'
$  for i in `cat file_name` 
>do 
>echo $i; 
>done

This User Gave Thanks to bankai For This Post:
pinga123
# 3  
Old 07-21-2010
Quote:
Originally Posted by bankai
Set your input field separator

Code:
$  IFS=$'\n'
$  for i in `cat file_name` 
>do 
>echo $i; 
>done

Its working for me . Please use $() instead traditional `` .
Code:
IFS=$'\n'
for i in $(cat Filename.txt)
do
echo $i;
done

# 4  
Old 07-21-2010
Quote:
Its working for me . Please use $() instead traditional `` .
Scripts should be written with portability in mind, hence the use of bourne syntax is highly advised
This User Gave Thanks to bankai For This Post:
pinga123
# 5  
Old 07-21-2010
Quote:
Originally Posted by bankai
Scripts should be written with portability in mind, hence the use of bourne syntax is highly advised
Thanks for the advise but few months earlier i was advised to use $() to make the script look better. However I also agree on ur point if $() is useless on other shell.


I have little doubt in my mind.
In my earlier code ,if IFS was set to space(assuming from the output).

Code:
for i in $(cat Filename.txt)
do
echo "$IFS $i"
done

Why would output shows space in every line.
output:
Code:
 My

 First

 Line

 My

 Second

 Line

It should have been without any space in line.
# 6  
Old 07-21-2010
Code:
for i in $(cat Filename.txt)
do
echo "$IFS $i"
done

Look at the example, why are you printing the IFS?

You need to set the IFS to a new line character -- this is not the default action.
# 7  
Old 07-21-2010
Quote:
Originally Posted by bankai
Code:
for i in $(cat Filename.txt)
do
echo "$IFS $i"
done

Look at the example, why are you printing the IFS?
that is the point. I just want to know what is the value of IFS without assigning it a new line character.
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