Shell Programming and Scripting

Hi all,

We have a requirement like,

There will be a file. For example the content will be as follows

+=KA100012345678 0114092150R328abcdefgh
D 345626 011409
1 2121212 232323 12121212 2323232323 1212121

We need to select the bold portion and change it to a different number, lets assume the new number will be 123456. There will be thousands of files and in each files we need to select the second string of digits as in the above example, and the strings will be different in all the files.

We need to do it in Unix. Any suggestion will be highly appreciated.

Thank you for your time.

Regards
Susant

Hi
This may help you

Code:

 
sed 's/pattern1/pattern2/g' filename > filename2

above command will replace pattern1 by inserting patter2.
also g is for global replacement if you want to replace only one occurance then use

Code:

 
sed 's/pattern1/pattern2/1' filename > filename2

Thanks
SHa

Thank you SHa for your quick reply. But the problem is we need to replace different string in the second line second position in thousands of files. I need a logic which will select the second string and replace the same with 12345.

Regards
Susant

Please help someone

sorry i did not get your query..

could you give some sample that you required..

Thanks
SHa

Thank you.

Suppose i have two files

file1.dc

+=KA100012345678 0114092150R328abcdefgh
D 345626 011409
1 2121212 232323 12121212 2323232323 1212121

file2.dc

+=KA100012345678 0114092150R328abcdefgh
X 345268 908789
1 2121212 232323 12121212 2323232323 1212121

and so on. There can be thousands of files with different data. We just need to change the bold data in all the files to 123456.

Thank you once again SHa.

Regards
Susant

can try a simple script as such:

for i in `cat filelist`
do
v1=`cat $i | head -2 |tail -1|awk '{print $2}'`
cat $i | sed "s/$v1/123456/1" > tempfile
mv tempfile $i
done

where filelist is a file containing all the files to be examined/replaced ie contains file1.dc file2.dc