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1. Kuba Orlik (kuba@toot.kuba-orlik.name)'s status on Thursday, 06-Jun-2024 02:46:47 JST Kuba Orlik

   Ok so here's a linux question that's been bugging me for years.

   I sometimes `less` to display/paginate a streaming stdout from another program. When I press `END` key on the keyboard, it brings me to the bottom of the stream, the latest data it has.

   Then it says "Waiting for data... (^X or interrupt to abort)"

   I want it to stop waiting for data and let me scroll up as it usually does when it's not waiting for data.

   (1/2)

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   • Kuba Orlik (kuba@toot.kuba-orlik.name)'s status on Thursday, 06-Jun-2024 02:47:40 JST Kuba Orlik

     in reply to

     I've tried pressing Control+X and Control+C, but it just closes less immediately instead of just interrupting the wait for new data.

     What do I press to make it stop waiting for data, not just close itself?

   • Kuba Orlik (kuba@toot.kuba-orlik.name)'s status on Thursday, 06-Jun-2024 02:49:47 JST Kuba Orlik

     in reply to

     This would particularly useful for browsing `journalctl` output 🙏

   • Kuba Orlik (kuba@toot.kuba-orlik.name)'s status on Thursday, 06-Jun-2024 04:18:56 JST Kuba Orlik

     in reply to

     • thomasmey

     @thomasmey In my case it just kills `less`. At least when using less indirectly with `journalctl`

   • thomasmey (thomasmey@social.tchncs.de)'s status on Thursday, 06-Jun-2024 04:18:57 JST thomasmey

     in reply to

     @kuba ctrl+c should stop waiting but not exit less

   • Kuba Orlik (kuba@toot.kuba-orlik.name)'s status on Thursday, 06-Jun-2024 04:20:23 JST Kuba Orlik

     in reply to

     • delta_onenature

     @delta_onenature pressing `q` has no effect for me :<

   • delta_onenature (delta_onenature@mastodon.xyz)'s status on Thursday, 06-Jun-2024 04:20:25 JST delta_onenature

     in reply to

     @kuba

     I believe a simple 'q' for quit should do the trick

   • Ben Zanin (gnomon@mastodon.social)'s status on Thursday, 06-Jun-2024 05:32:51 JST Ben Zanin

     in reply to

     @kuba you're doing the right thing! Or at least you're doing what should produce the result you want according to the default configuration of less(1).

     However you say you're invoking less "indirectly" with journalctl; do you mean you're running `journalctl ... | less`, or just running `journalctl` and letting it invoke less(1) itself as the default pager? If the latter, it's useful to know that systemd invokes less with some quite non-default options!

     https://github.com/systemd/systemd/blob/main/src/shared/pager.c

     1/2

     Kuba Orlik repeated this.
   • Ben Zanin (gnomon@mastodon.social)'s status on Thursday, 06-Jun-2024 05:32:53 JST Ben Zanin

     in reply to

     @kuba If you consult the systemd documentation and the entries for $SYSTEMD_PAGER and $SYSTEMD_LESS¹ you'll find mention of some mysterious less(1) options but not what they mean or why they matter; but if you peek at the doc source code² you'll find that the behaviour you're describing is controlled by the presence of "K" in the default $SYSTEMD_LESS var, and you can override that out with, e.g.:

     ```
     SYSTEMD_LESS='FRXM' journalctl
     ```

     ¹: https://www.freedesktop.org/software/systemd/man/latest/systemd.html#$SYSTEMD_PAGER

     ²: https://github.com/systemd/systemd/blob/60a20eff8007105c4a09ab34ebe318d5970e629a/man/common-variables.xml#L112-L155