tailing logs

I came across /u/asboans asking¹ for tips on following logs in Emacs. And it occurred to me that I don't tail logs that often these days. This is due to using tools like Sentry, and Datadog at $work.

But that's not to say that tailing the logs in the terminal has gone the way of the dodo, or that it is no longer necessary. Just that it's not something I've had to do in a long time.

The poster is asking for tips on following logs inside emacs, and also filtering them. As I said, I don't have to use tail right now, but even when I had to in the past, I never thought of reaching to Emacs for that. My habit has been to always use the termainal like vterm and tail the log like this.

tail ../path/to/logs/*.log

A commenter suggests using auto-revert-tail-mode² which is apparently similar to auto-revert-mode. This is built in and a preferable one for me to try.

But how is auto-revert-mode different to this? From what I could gather in the docs, -tail-mode sibling seems to be tailored for files that are appended at the bottom. So it won't revert the whole buffer, just tails it like tail -f.

One thing to note is that the buffers are like any other emacs buffers so the regular cautions with opening large files in emacs still applies.

Another user recommended using the logview³ package. Looks very featureful. Originally designed to target log files by java programs like Log4j, but has no java specific requirement as long as the logs follow similar format. I didn't try it myself but this seems useful if you're in need of a proper log viewer.

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