From the tail(1) man page: With --follow (-f), tail defaults to following the file descriptor, which means that even if a tail’ed file is renamed, tail will continue to track its end. This default behavior is not desirable when you really want to track the actual name of the file, not the file descrip- tor (e.g., log rotation). Use --follow=name in that case. That causes tail to track the ...
It means tail -f command will wait for new strings in the file and show these strings dynamically. This command useful for observing log files . For example try, tail -f /var/log/messages.
Tail will then listen for changes to that file. If you remove the file, and create a new one with the same name the filename will be the same but it's a different inode (and probably stored on a different place on your disk). tail -f fill not retry and load the new inode, tail -F will detect this.
I'd like to be able to tail the output of a server log file that has messages like: INFO SEVERE etc, and if it's SEVERE, show the line in red; if it's INFO, in green. What kind of alias can I set...
A simple pipe to tail -n 200 should suffice. Example Sample data. $ touch $(seq 300) Now the last 200: $ ls -l | tail -n 200 You might not like the way the results are presented in that list of 200. For that you can control the order of the results that ls outputs through a variety of switches. For example, the data I've generated is numeric.
Here is what I know I can do: tail -n 15 -F mylogfile.txt As the log file is filled, tail appends the last lines to the display. I am looking for a solution that only displays the last 15 lines and get rid of the lines before the last 15 after it has been updated. Would you have an idea?
Also, I would at least consider using tail -f instead of cat so that the output can be followed in near-realtime. You may want to look at the OPs comment to this answer which is basically the same as yours.
Say I have a huge text file (>2GB) and I just want to cat the lines X to Y (e.g. 57890000 to 57890010). From what I understand I can do this by piping head into tail or viceversa, i.e. head -A /...
tail -f | nl works for me and is the first what I thought of - that is if you really want the lines numbered from 1 and not with the real line number from the file watched. Optionally add grep if needed to the appropriate place (either before or after nl). However, remember that buffering may occur. In my particular case, grep has the --line-buffered option, but nl buffers it's output and ...
When I do tail -f filename, how to quit the mode without use Ctrl+c to kill the process? What I want is a normal way to quit, like q in top. I am just curious about the question, because I feel ...