"Invalid or incomplete multibyte or wide character" running v4l2-ctl

Question

Using iTerm, I'm SSHing into my raspberry pi (raspbian) to control a home security system I've setup.

I need to change the focus of my camera, so I'm running v4l2-ctl -c focus_absolute=0 on my terminal.

I've been doing this for weeks, and it hasn't given me any issues. Today, when running the command I've started getting the following error:

VIDIOC_S_EXT_CTRLS: failed: Invalid or incomplete multibyte or wide character
focus_absolute: Invalid or incomplete multibyte or wide character

What could be causing it to suddenly be throwing this error? I've been running the exact same command for weeks without a problem.

Answer 1

I found the answer in here: https://askubuntu.com/a/388045/814834. Turns out that when, for example, the camera's auto_exposure setting is set to 1 (true) then, whenever you modify settings that are controlled by that "automatic" setting, in this case the absolute_exposure, you will get that useless error because you have to first change the auto_exposure to 0 (false) in order to change the settings controlled by it