tail -F

tail -F -q and piping to other commands (configuring buffering of other commands)

why-tail-F-instead-of-f

If you want to pipe output of tail -F to commands like grep or jq then look into configuring them so they buffer per line rather than holding on to larger buffers, look at the following notes:

• GREP_OPTIONS-using-line-buffered
• buffering-issue

Also make sure to user -q when piping structured logs (like JSON per line logs) to tools like jq.

with: stdbuf -oL

IF you are working with a file that does not end with an empty line, and you are piping the content from tail -F then prefix tail -F with stdbuf -oL.

Otherwise tail -F is NOT going to output the last line from your file. And you could end up with very confusing tailing missing that last event.

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