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Environment Variable Warnings [solved]

  • Hi All,

    I'm running into a strange issue in QT. I suspect I have not set up something correctly but I am hoping someone can point me down the right direction. I am developing an application to be deployed on an embedded Linux system. I would like the program to autorun at startup. When I put my program into ~/.bashrc (sudo /pathtofile/file) QT complains that I have not set some environment variables ( and the GUI displays incorrectly. However when I exit the application and run it manually from the terminal everything executes correctly.

    Does anyone have any suggestions about what might be happening? I am not sure why the environment variables are not being set such that QT can read them.

    The errors specifically are:

    EGLFS: Unable to query physical screen size, defaulting to 100 dpi.
    EGLFS: To override, set QT_QPA_EGLFS_PHYSICAL_WIDTH and QT_QPA_EGLFS_PHYSICAL_HEIGHT (in millimeters).
    EGLFS: Unable to query screen depth, defaulting to 32.
    EGLFS: To override, set QT_QPA_EGLFS_DEPTH.

    Thanks for your help,


  • I figured it out. I was sourcing the file in the wrong way. I needed to put the command into a script like this:

    cd /location/of/file/

    And that seemed to work. I don't fully understand why that worked so if anyone has anything to enlighten me that would be great.



  • Lifetime Qt Champion


    Depending on the OS on your board (debian, openembedded, other ?) you might not be using the right technique to start your application.

    You should check what startup system software you have and use it for that purpose

    Hope it helps

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