06-15-2014
awk last n lines of file
Just my second week working on awk I need a hint for the following tasks.
I want to limit my logfile from the very outset to 200 lines. All I do until now is
head -c 10K >> /home/uplog.txt | awk 'END{print NR " swap " NF$5; exit}' /home/uplog.txt;
After being read it shall print the very last record " some text " of the fifth field and right after that exit, due to the size of the file.
How can I set the limit to a certain number of lines?
My wiry selfmade logfile should be read only the last n lines, e.g. 10. I've been typing something like NR-1 but that gives just the line before the very last one. So how can I set a range like NR>=1&&NR<=5 or even more sophisticated /~^start !/,/~^stop !/ ?
If someone can give me a hint that would be great, thanks in advance.
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