USB Error: (iokit/common) exclusive access and device already open

[apexJCL]

System information:

• macOS Ventura v13.0.1
• Apple M1 Pro

I get this error whenever I try to launch the application after the setup screens. I've tried removing the app but to no avail.

Any clues/suggestions?

[tillt]

Are you running the latest version of Komplete Synthesia (v0.50 release)?

Assuming you are. Before starting KompleteSynthesia.app, please run the following in your terminal:

ps aux |grep NIHardware

ps aux |grep NIHost

ps aux |grep NTK

Then start KompleteSynthesia, try the same three steps again after having started KompleteSynthesia. Let me know what you saw.

Right now I am assuming some Native Instruments service was still blocking the access to the USB interface, needed for transferring image data to those screens. KompleteSynthesia tries to identify those services when starting and tries to kill them before accessing the USB device. Maybe that fails for you somehow.

[apexJCL]

Yes, latest version, sorry I forgot to mention that.

On Sun 5 Feb 2023 at 10:09 Till Toenshoff @.***> wrote:

Are you running the latest version of Komplete Synthesia (v0.50 release)?

— Reply to this email directly, view it on GitHub https://github.com/tillt/KompleteSynthesia/issues/9#issuecomment-1418204298, or unsubscribe https://github.com/notifications/unsubscribe-auth/AA6ZYAH6OK456KFVOGYDCTTWV7UFPANCNFSM6AAAAAAURLGH3E . You are receiving this because you authored the thread.Message ID: @.***>

[tillt]

I did in fact already find at least one bug in the relevant code by now - namely the NTKDaemon would not be treated correctly. Is it by any chance that one that is running on your machine and blocks access?

ps aux |grep NIHardware

ps aux |grep NIHost

ps aux |grep NTK

Please let me know what those commands did when run in your Terminal.app.

[apexJCL]

It seems there's both NIHardware and NIHostIntegrationAgent processes running in the background:

➜  ~ ps aux |grep NIHardware

ps aux |grep NIHost

ps aux |grep NTK

carlos             636   0.0  0.1 409942544  22240   ??  S    Sat11AM   0:05.60 /Library/Application Support/Native Instruments/Hardware/NIHardwareAgent.app/Contents/MacOS/NIHardwareAgent
carlos           36039   0.0  0.0 408626880   1296 s000  S+    7:40AM   0:00.00 grep --color=auto --exclude-dir=.bzr --exclude-dir=CVS --exclude-dir=.git --exclude-dir=.hg --exclude-dir=.svn --exclude-dir=.idea --exclude-dir=.tox NIHardware
carlos             632   0.0  0.2 409946528  29136   ??  S    Sat11AM   0:56.89 /Library/Application Support/Native Instruments/Hardware/NIHostIntegrationAgent.app/Contents/MacOS/NIHostIntegrationAgent
carlos           36041   0.0  0.0 408626880   1296 s000  S+    7:40AM   0:00.00 grep --color=auto --exclude-dir=.bzr --exclude-dir=CVS --exclude-dir=.git --exclude-dir=.hg --exclude-dir=.svn --exclude-dir=.idea --exclude-dir=.tox NIHost
carlos           36043   0.0  0.0 408626880   1296 s000  S+    7:40AM   0:00.00 grep --color=auto --exclude-dir=.bzr --exclude-dir=CVS --exclude-dir=.git --exclude-dir=.hg --exclude-dir=.svn --exclude-dir=.idea --exclude-dir=.tox NTK

[tillt]

Those are the problem - if you killed them manually

killall -9 NIHardwareAgent
killall -9 NIHostIntegrationAgent

then restart KompleteSynthesia -> it should be better now.

Now question is why they dont get killed by KompleteSynthesia as intended? Guess I need to do some more research...

And don't worry - killing them won't be an issue. You can either manually restart them after KompleteSynthesia was terminated, or you can just relog into your macOS user, that'll restart them as well.

For restarting them manually, run the following in your terminal:

open "/Library/Application Support/Native Instruments/Hardware/NIHostIntegrationAgent.app"
open "/Library/Application Support/Native Instruments/Hardware/NIHardwareAgent.app"

The idea was the KompleteSynthesia does exactly that.

on startup:

• identify if any of those three processes was running
• kill all of them

on shutdown:

• restart those that ran when starting

In any case, thanks for letting me know about that problem, Jose - I will fix that issue, it just may take a few attempts and a bit of patience. Would be great if I found a way to reproduce it....

[tillt]

Also, please give 0.51 a try - some changes in there that might do the trick for you - without manual intervention.

[apexJCL]

I had to manually kill both processes but after doing so, it worked!

Thanks for the quick response ❤️

[tillt]

Glad that worked.

With 0.51, when starting without doing anything extra, what happens? I wonder if that process killing and waiting for it to be truly gone was doing the job now or not.

Thanks again for your help in getting this problem solved!

[apexJCL]

It is not waiting for the process to be killed, it just throws the same error as before.

I'm not too familiar with Objective-C so I can't help (for now).

[tillt]

Really, the same error? So it says "exclusive access..." blah --- it does NOT say "Failed to terminate ..."?

[apexJCL]

https://user-images.githubusercontent.com/4037632/217296545-49598ba9-4534-4bd0-9a03-88298295680e.mp4

[tillt]

oh wow - that is very helpful indeed - I had not considered it behaving like that. We are onto something....

[tillt]

@apexJCL please give 0.52 a shot - I may have identified the problem...

[apexJCL]

Just tested and everything seems to be working just fine (both at open and closing the app).

Excellent work, highly appreciated 🙏🏼