OK. It looks like locate.updatedb isn't fully implemented in OSX. It doesn't pay attention to options about excluding paths from indexing.
Here's another MacOShint that's more on target:
Make the locate command ignore certain directories. What I tried first is
Code:
$ sudo /usr/libexec/locate.updatedb ---prunepaths=/Volumes/Backup\ HD/
It doesn't make any difference.
I then found a thread on MacOSX.com suggesting that OSX doesn't pay attention to prunepaths,
locate.updatedb's options not working. (Scroll down to cilly's post.)
I'm left with editing Apple's locate.updatedb script, which I'm not willing to do, or living with long results from locate queries. There is another possibility:
Does anyone know what the alias would look like (in my .bashrc) to redefine 'locate' to filter out /Volume/Backup\ HD? Something with grep?
I suppose I could also backup to a sparseimage in Backup HD.