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[Bug 1518726] [NEW] Webcam cannot start after interrupted access with "VIDIOC_STREAMON: Invalid argument"


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I am trying to make my first application in C++ with OpenCV, where I am trying to capture images from the built-in webcam on my Lenovo T450s. I use Eclipse CDT as my IDE to write code and debug. During several trials, sometimes I need to STOP running applications via Eclipse (probably through some interrupt signal). Whenever the application is interrupted, during the next run it cannot access the webcam and is returning
"VIDIOC_STREAMON: Invalid argument"

Apparently this is because resources are not released due to the
interrupt. Also VLC cannot access webcam after I start seeing this

Apparently there are 1-2 reports about this issue related to OpenCV and kernel, and there is also a workaround by handling SIGINT properly and correctly exiting. I could not work that solution in Eclipse, because probably Eclipse STOP button does not send SIGINT but some other signal. Nevertheless, I was expecting kernel to handle this in another way, so that resources would be released automatically to allow other applications to access webcam.
However, webcam cannot be accessed after a program is interrupted.

lsb_release -rd
Description:	Ubuntu 14.04.3 LTS
Release:	14.04

uname -r


Please don't hesitate to ask for more information about the issue and
correct me if my report isn't useful or sufficient.

** Affects: v4l-utils (Ubuntu)
     Importance: Undecided
         Status: New

** Tags: webcam
Webcam cannot start after interrupted access with "VIDIOC_STREAMON: Invalid argument"
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