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Suppose some logs is being rotated by size 50MB each . I did 'grep' some string and my string is present in log file, log_3 and I want to copy content of log_3 before it gets rotated(renamed) to log_4 . Please suggest how to take backup of content of log_3 before it is rotated . I just need the content of log_3 . I don't want like I copied log_3 (by cp -p log_3 log_3_backup) but by that time logs got rotated and now log_3_backup contains content of log_2 .Is there any way we can do to avoid this . Working on an automation project I need a solution to this . Thank you very much for your suggestions in advanced . You May share python or shell script .

LMC
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user3148161
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1 Answers1

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You can get the file inode number that won't change if renamed, then reference the file by that name

for f in *.log; do
    # get inode of file
    iname=$(ls -i $f)
    # test file contents for pattern presence 
    if grep -q 'some pattern' $f; then
        # the file contains the searched pattern, let's do something
        # find by inode number and move it
        find -inum $iname -exec mv {} {}.bak ';'
    fi
done

Perhaps getting a backup of the file is not necessary anymore, let's grep it again

find -inum $iname -print0 | xargs -r0 grep 'some pattern'
LMC
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