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Framebuffer cursor blinking after Application exit

  • 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.

  • Lifetime Qt Champion

    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 ?

  • 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_FBDEVICE=/dev/fb0
    export TSLIB_TSDEVICE=/dev/input/event2
    export TSLIB_CALIBFILE=/etc/pointercal
    export TSLIB_CONFFILE=/etc/ts.conf
    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.

  • Lifetime Qt Champion

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

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