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File handling in UNIX


 
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# 1  
File handling in UNIX

Hi All,
I want to read a file in UNIX line by line.

Can u suggest me any command for this?
# 2  
Depends on what you want to carry out.

Here is one solution
Code:
#! /bin/sh
for i in $(cat file.name)
do
echo " This is the line just read $i"
done

The above assumes you have a file and you want to read the contents line by line.

Suppose you want to input lines to a file from the standrd input, then this would do

Code:
#! /bin/sh

while read line
do
echo $line >> file.name
done


Vino
# 3  
In Vino's post the first method would be better done like this:

Code:
#! /bin/ksh

while read line
do
    echo $line >> outputfile.name
done < inputfile.name

note the the only change from the second one is the bit in bold. In his example $(cat file.name) is incorrect since his example was using sh as it's shell that syntax is used in ksh/bash not sh, also it is a UUOC, basically cat file.name is a waste of a process, since the shell can handle the input from a file.
# 4  
See the Tips and Tutorials Section for 12 methods for reading/parsing a file.
# 5  
Reborg,

I stand corrected.

Thanks
 

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