Interesting, didn’t know about that. Hadn’t thought about it too deeply.

  python <<<'import subprocess; subprocess.run(["ls", "-la", "/proc/self/fd"])'

Running under zsh, link 0 -> '/tmp/zshqqjTS0 (deleted)'; under bash, link 0 -> 'pipe:[1509353]'.

(I know <(…) is substituted in zsh with /proc/self/fd/… for a fd corresponding to a pipe:[…], and regular | piping makes 0 be a pipe:[…].)

I know some common configurations use concrete /tmp. Mine is tmpfs.

Thanks for the info! I like sharing these kinds of things because I have found them interesting and expect a few others will too, and people often add to them details I hadn’t known and like to know!