Unsolved Framebuffer cursor blinking after Application exit

[Simon2210]

Hi,

my QWidget-Application uses the linux framebuffer directly.
By default the console cursor is drawn at the top left corner. I prevent it by setting "vt.global_cursor_default=0" in my bootloader and export "QT_QPA_PLATFORM="linuxfb:tty=/dev/null" at runtime.

Only if my application is finished, the cursor is shown again.
I would like to know why the exit causes the cursor to reappear.
Does anyone have an idea?

Thank you.

[SGaist]

Hi and welcome to devnet,

What version of Qt are you using ?
On what distribution ?

How are you starting your application ?
How are you stopping it ?

[Simon2210]

Thanks,

I'm using Qt 5.6.1. The distribution based on arm and is selfmade by buildroot. There is no window-server installed. It is running on a cl-som-imx7 from compulab.
I start the application (without arguments) via SSH or at startup with the start-stop-daemon tool as background process with the following environment:

export TSLIB_TSEVENTTYPE=H3600
export TSLIB_CONSOLEDEVICE=none
export TSLIB_FBDEVICE=/dev/fb0
export TSLIB_TSDEVICE=/dev/input/event2
export TSLIB_CALIBFILE=/etc/pointercal
export TSLIB_CONFFILE=/etc/ts.conf

export QT_QPA_FB_DISABLE_INPUT=1
export QT_QPA_GENERIC_PLUGINS="evdevkeyboard:/dev/input/event0,tslib:/dev/input/event2"
export QT_QPA_PLATFORM="linuxfb:tty=/dev/null"

I can stopping it by "QApplication::exit()", SIGINT or SIGTERM - always the same behavior.

[SGaist]

Did you try echo 0 > /sys/class/graphics/fbcon/cursor_blink before starting your application ?