Linux find/search root partition ONLY?

Question

Say I need to do:

find / -name somefile.txt

and say root partition / is mounted on /dev/sda5; however, let's say I also have 250GB partitions (/dev/sda6, /dev/sda7) mounted in /media - AND another location that I cannot currently remember. Say, also, that I know the file I'm looking for is on /dev/sda5.

Obviously, the above command will also descend in /media and that other directory which represent the big partitions, wasting time in looking for the file in the wrong place.

Is there a way to instruct find (or other command) to search only / on /dev/sda5, and NOT to descend to directories if they are on different partitions?

Answer 1

Use the -xdev argument to find

-xdev Don’t descend directories on other filesystems.

Answer 2

The POSIX standard defines the -xdev ”primary“:

it shall cause find not to continue descending past directories that have a different device ID

This is implemented in GNU's find (i.e. the findutils; docs).
GNU find also allows you to use -mount as ”an alternate name for -xdev, for compatibility with some other versions of find.“

On BSD systems and macOS the option is -x instead. They (imho confusingly) call -xdev to be ”deprecated“. You can, however, use -mount instead. [manpages of FreeBSD and macOS]

other tools, just FYI

If you're using ripgrep (rg) like rg --files, you can use the --one-file-system option, which does the same like find's -xdev option.