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Old 05-18-2012, 02:29 AM   #1
Simon1984
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Shell script to find a filename in a folder & change text within the file


Hi there.

I don't have much experience or any training with shell scripts so please forgive any stupid questions or mistakes.

I have a folder that contains different files. I need a script that will find only files that have the word "CYCLIC" in the filename and for those files only, find and replace any text within the file that matches "CTRRET" with "CYCLIC_CTRRET".

Here is what I have come up with after taking bits and pieces from various forum discussions, but it doesn't work. I'm hoping someone could show me where I'm going wrong.

*******************************************

#!/bin/bash

basePath="/cygdrive/$DOC1_DRIVE/conret/"

for f in $basePath
do
if [ $fn = *CYCLIC* ]
then
sed -i "s/_CTRRET/_CYCLIC_CTRRET/g" "$f"
fi
done

*******************************************

I'd appreciate any help anyone could provide.

Thank you.
 
Old 05-18-2012, 02:44 AM   #2
colucix
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Basically in your script the offending line is
Code:
if [ $fn = *CYCLIC* ]
where fn is not the loop variable and the comparison does not make sense. Not to mention the loop cycles only once over the value of the basePath variable. My suggestion is to keep it simple and use a one-line stream of commands, e.g.
Code:
grep -Zrl CYCLIC $basePath | xargs -0 sed -i 's/_CTRRET/_CYCLIC_CTRRET/g'
Feel free to ask if something is not clear about this command.
 
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Old 05-18-2012, 03:57 AM   #3
pan64
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why don't you execute
Code:
sed -i 's/_CTRRET/_CYCLIC_CTRRET/g' $basePath/*CYCLIC*
it will send an error message if there was no such file, otherwise it works




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Old 05-18-2012, 04:23 AM   #4
colucix
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Quote:
Originally Posted by pan64 View Post
why don't you execute
Code:
sed -i 's/_CTRRET/_CYCLIC_CTRRET/g' $basePath/*CYCLIC*
it will send an error message if there was no such file, otherwise it works
This would work if the files were all in the same directory, but it's not recursive. Anyway, you make me notice that the word CYCLIC must be in the filename, not inside the file. Therefore instead of grep we can use find to search recursively inside the base directory:
Code:
find $basePath -name \*CYCLIC\* -exec echo sed -i 's/_CTRRET/_CYCLIC_CTRRET/g' {} \;
@Simon1984: please notice the echo command after -exec: it is for testing purposes. It will display the sed commands without actually execute them, so that you can check the result to see if it works as expected.
 
Old 05-18-2012, 04:35 AM   #5
pan64
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Quote:
Originally Posted by colucix View Post
This would work if the files were all in the same directory, but it's not recursive.
That's why:

Quote:
Originally Posted by Simon1984
Hi there.

...

I have a folder that contains different files.
Also based on the original "script" there are no subdirs in this case. But I'm not really sure
 
Old 05-18-2012, 06:14 AM   #6
colucix
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Quote:
Originally Posted by pan64 View Post
Also based on the original "script" there are no subdirs in this case. But I'm not really sure
Let's see. The OP should clarify (hopefully).
 
Old 05-18-2012, 07:09 AM   #7
Simon1984
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thanks for the suggestions guys

All my files are in the same folder so I tried the following code and it works fine

sed -i 's/_CTRRET/_CYCLIC_CTRRET/g' $basePath/*CYCLIC*


I appreciate all the suggestions and feedback as it's helped me to understand a bit more about how the code works.

Thanks again!
 
  


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