Error/conflict with Jettison

I recently installed https://www.stclairsoft.com/Jettison/ to automatically eject mounted external drives on sleep, and occasionally I've been getting an error from Jettison:

Code: Select all: Techno Pop - 86Z3GCJ4MF.com.noodlesoft.Hazel is using 501

("Techno Pop" is the name of my external drive)

I get this error when I close the lid on my MBP to put it to sleep, rather than when the system goes to sleep by itself. When this happens, Jettison fails to unmount the external drive. I don't have any rules in Hazel specific to that drive. Is there something that Hazel does in the background that would block other apps from mounting/unmounting drives?

Are you familiar with the commandline? You could try the lsof command to see what file/dir is being held open.

Alternatively, you can launch Activity Monitor. Find the process in question, select it and do "Inspect Process". Click on the "Open Files and Ports" tab and see if anything on that drive is listed there.

hmmm- I'm seeing that the process with PID 501 is findmybeaconingd, which doesn't seem to be using anything on that drive:

/
/usr/libexec/findmybeaconingd
/Library/Preferences/Logging/.plist-cache.gD6lUl7r
/System/Library/CoreServices/SystemVersion.bundle/English.lproj/SystemVersion.strings
/private/var/db/com.apple.findmy.findmybeaconingd/Storage.db-shm
/usr/share/icu/icudt74l.dat
/dev/null
/dev/null
/dev/null
/private/var/db/com.apple.findmy.findmybeaconingd/Storage.db
/private/var/db/com.apple.findmy.findmybeaconingd/Storage.db-wal
/private/var/db/com.apple.findmy.findmybeaconingd/Storage.db-shm
/private/var/db/com.apple.findmy.findmybeaconingd/Storage.db
/private/var/db/com.apple.findmy.findmybeaconingd/Storage.db-wal

I don't think 501 is supposed to be the PID. In Activity Monitor, find the Hazel process mentioned by Jettison and check it's open files.

OK, I'm not a pro at the command line but Activity Monitor wasn't giving me what I think I was needing so after consulting the lsof man page, I did this:

Code: Select all: sudo lsof -c 86Z3GCJ4MF.com.noodlesoft.Hazel

and at the end of all of the open files, there's this:

Code: Select all: COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME 86Z3GCJ4M 1441 stewart 11r DIR 1,24 672 178860 /Volumes/Techno Pop/.Trashes/501

...that's the only file listed that appears on my external drive.

Doing a little more digging- I did

Code: Select all: sudo ls -a /Volumes/Techno\ Pop/.Trashes/501

and it returned a bunch of MP3 files I'd deleted a while ago.

Code: Select all: sudo rm -rf /Volumes/Techno\ Pop/.Trashes/501/*

seems to have wiped them out, so we'll see if there's a conflict with Jettison and Hazel now. Though I'm still curious as to why Hazel was handling that folder anyway- I don't have any rules that would affect the /Volumes/.Trashes folder?

Check the settings. There are options to manage the trash there.

I have App Sweep turned on, and also "Delete files sitting in the trash for more than 1 month". Would either of those be affecting the external drive?

Technically it shouldn't in that Hazel does not keep an open file for those functions in general. Does the problem persist after a reboot?

Yes, I've rebooted and the issue seems to persist. Another thing I've noticed- it seems that if I delete a music file from Apple Music, the deleted music files end up in the /Volumes/*disk name*/.Trashes/501 folder until I sudo-delete them. Not sure what's causing that behavior, but it doesn't seem to make a difference- I'm still getting that error message from Jettison and when I ls the contents of /Volumes/*disk name*/.Trashes/501, it's empty.

Does the problem still happen if you disable all of Hazel's trash functions?

Yes, even with those options disabled I'm still getting that error.

Have you rebooted since disabling those options?

So far, so good. Not seeing that error, even after completely shutting down and restarting after a couple days.