Question

I’ve got log file, which I would like to have 60 lines in.
When there will appear 61 line, script should cut line from beginning and paste it at end of my backup log file.

But I have not any idea how to do that. Can you help me?

Answer 1

Use a combination of:

1. tail --lines=60 my_log to get the last 60 lines of your log file
2. head --lines=-60 my_log to get all but the last 60 lines of your log file

I’m sure you can figure the rest out 🙂