On 09/07/18 17:27, SunBear wrote: > I see the following message from Shotwell 0.22.0 in Ubuntu 16.04 > every time a iPhone4s is plugged in to my computer usb: > > Shotwell Unable to fetch previews from the camera: Could not claim > the USB device (-53) > > I have to click "Ok" to remove this message before I can access > Shotwell. This warning has always appeared for a few years. Annoying. > It will be great that this warning be removed.
You are very lucky that clicking OK enables you to proceed like that. This is a well-known and pervasive bug which has remained unfixed for many years, for some unknown reason. "Could not claim the USB device (-53)" means that some other process (I believe a driver of some kind) has already grabbed the device without authorization, and will not let go of it. This kind of usurpation is not really something we want in an operating system. We need to get to the bottom of it, and delete the process which is apparently jumping in where it is not wanted. I am guessing — because I cannot find any concrete information — that it is a kernel driver installed for some other, perfectly authentic, reason, which is doing this as an unwanted side-effect, so the author may be completely unaware that this is happening. I have already recommended elsewhere that the correct interim solution is for camera applications (in your case, Shotwell, but in fact almost anything that needs access to the camera, even a plain file manager) to be able (with sudo authentication) to kill the current claiming process, break the lock, and give the application the access it needs. Long term, it should be possible to identify to the user *what* process has claimed the USB device uninvited, and allow the user to kill the process permanantly (ie remove it from whatever autostart procedure it was spawned from). Until that happens, camera software usage is largely crippled. ///Peter -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1400470 Title: cannot download photos using shotwell via usb To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/shotwell/+bug/1400470/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs