A good use case is to redirect output into a file you only can modify with sudo.... | Hacker News

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		denisw on Feb 8, 2015 \| parent \| context \| favorite \| on: Bash process substitution A good use case is to redirect output into a file you only can modify with sudo. Trying to do it like this doesn't work: `sudo echo "fs.inotify.max_user_watches=1000000" > /etc/sysctl.conf` as the redirection happens within the shell, thus without root permissions. However, the following does work: `echo "fs.inotify.max_user_watches=1000000" \| sudo tee /etc/sysctl.conf` as the writing is done by the elevated tee process.

derefr on Feb 8, 2015 [–]

That seems like an anti-unixism (operating with multiple EUIDs in a single process group), though I'm not too sure what the equivalent unixism would be—maybe something with a daemon and a spool directory? Or a user-writable FIFO, redirected to the correct file by the elevated user in a separate command?

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