Solved

Bash string comparison

Posted on 2009-05-20
6
1,500 Views
Last Modified: 2013-12-26
I am trying to find a way to compare the contents of a flat file with a variable.

For example something like this:

if ${STRING} exists in /file.txt then ignore
else
add to file

I am not sure of the exact syntax to compare file contents with a variable so any help on this would be great. Thanks.
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Question by:Sam Cohen
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6 Comments
 
LVL 84

Accepted Solution

by:
ozo earned 500 total points
ID: 24433595
if grep -i "${STRING}" /file.txt ; then echo  ignore
else
echo ${STRING} >> /file.txt
fi
0
 
LVL 8

Author Comment

by:Sam Cohen
ID: 24434211
I toyed around with that to see if I could implement it into the pre-existing code and I was running into syntax errors. Here is the code I am working with.

if [ -n "${IPADDR}" ]; then
for IP in ${IPADDR}; do
/bin/logger -p authpriv.warn -t ban "${IP} blocked. Check /etc/hosts.deny"
echo "${IP}  #Blocked : `date +%Y%m%d`" >> /root/test
done
    else
     /bin/logger -p authpriv.warn -t ftp_ban "All Clear"
fi

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0
 
LVL 8

Author Comment

by:Sam Cohen
ID: 24434733
still not having any luck :( any suggestions on a better way to accomplish this?
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LVL 84

Expert Comment

by:ozo
ID: 24435275
where do you want to implement a comparison into the pre-existing code ?
0
 
LVL 8

Author Closing Comment

by:Sam Cohen
ID: 31583578
I modified my code and got it to work. Thanks!
0
 
LVL 8

Author Comment

by:Sam Cohen
ID: 24435506
actually I got it to work, just needed to modify my code a bit more. Thanks!
0

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