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how to read the contents of two files line by line and compare the line by line?


 
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# 1  
Old 04-08-2012
how to read the contents of two files line by line and compare the line by line?

Hi All,

I'm trying to figure out which are the trusted-ips and which are not using a script file.. I have a file named 'ip-list.txt' which contains some ip addresses and another file named 'trusted-ip-list.txt' which also contains some ip addresses. I want to read a line from 'trusted-ip-list.txt' file and check whether the read value exists in 'ip-list.txt' file and write some log info to some other file named 'checked-trust.log' file.

Here is the code i'm trying.. But I'm not able to do so Smilie Smilie..

Code:
trust_file=trusted-ip-list.txt
ip_file=ip-list.txt

while ip= read -r line
do
       test=`grep -w "$line" $ip_file`
       echo " "
       if [ "$ip" -e "$test" ] ; then
           echo "Trusted access at `date` by $line" > checked-trust.log
       else
           echo "Untrusted access at `date` by $line" > check-trust.log
       fi
done < "$trust_file"

Please help me in solving this.. Waiting for a helping hand..

Last edited by Scrutinizer; 04-08-2012 at 04:52 PM.. Reason: code tags
# 2  
Old 04-08-2012
You are not setting the variable $ip .

It seems to me you are confusing
Code:
while ip= read -r line

Code:
while IFS= read -r line

no?

although I suspect you may want to leave that out, since you are doing a word match with it and like this it will contain any spaces in the input file..

I don't know what the
Code:
echo " "

is for.. (it's not written to the log)

$ip_file could use a pair of double quotes although with the filename contained therein, this is not strictly necessary..

If you still can't get it to work, please post sample input files...

Last edited by Scrutinizer; 04-08-2012 at 05:33 PM..
This User Gave Thanks to Scrutinizer For This Post:
# 3  
Old 04-08-2012
I've done a small change in the code. Please find it:

Code:
trust_file=trusted-ip-list.txt
ip_file=ip-list.txt

while read ip
do
       test=`grep -w "$ip" $ip_file`
       echo "The value of test is : $test"
       if [ "$ip" = "$test" ] ; then
           echo "Trusted access at `date` by $line" > checked-trust.log
       else
           echo "Untrusted access at `date` by $line" > check-trust.log
       fi
done < $trust_file

Even though it is not working.. When I run the script, I'm getting the following output:
Quote:
The value of test is:

The value of test is:

The value of test is:

The value of test is:

The value of test is:

The value of test is:

The value of test is:

The value of test is:
I'm not able to grep the $ip value from ip-list.txt file and set to "test" variable..
# 4  
Old 04-08-2012
This time the variable $line does not get set.
# 5  
Old 04-09-2012
Code:
#!/bin/bash

ip_file=ip-list.txt
trust_file=trusted-${ip_file}

while read ip; do
       if grep -w "${ip}" ${ip_file}; then
            value=Trusted
       else
            value=Untrusted
       fi
       echo "${value} access at $(date) by ${ip}" >> checked-trust.log
done < ${trust_file}


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