Qt runtime dependency

Kanni1303

Hi,
I am using pigpio in my project to use gpio and spi, the problem I'm facing is not able to run the applciation

when tried to run my application with sudo

sudo ./oilTemp

got error

QStandardPaths: XDG_RUNTIME_DIR not set, defaulting to '/tmp/runtime-root'
libEGL warning: DRI2: failed to authenticate
Unable to query physical screen size, defaulting to 100 dpi.
To override, set QT_QPA_EGLFS_PHYSICAL_WIDTH and QT_QPA_EGLFS_PHYSICAL_HEIGHT (in millimeters).
EGL Error : Could not create the egl surface: error = 0x300b

Aborted

When i tried to run without sudo

./oilTemp

I am getting following error

2019-05-16 00:16:11 gpioWrite: pigpio uninitialised, call gpioInitialise()
2019-05-16 00:16:11 gpioWrite: pigpio uninitialised, call gpioInitialise()
2019-05-16 00:16:11 gpioRead: pigpio uninitialised, call gpioInitialise()
2019-05-16 00:16:11 gpioWrite: pigpio uninitialised, call gpioInitialise()
2019-05-16 00:16:11 gpioWrite: pigpio uninitialised, call gpioInitialise()
2019-05-16 00:16:11 gpioWrite: pigpio uninitialised, call gpioInitialise()
2019-05-16 00:16:11 gpioRead: pigpio uninitialised, call gpioInitialise()

Kent-Dorfman

This is not a Qt problem, per se, but your lack of understanding how X11 display authentication works. When you sudo you lose the xauth credentials that allow your app to talk to the display hardware.

You should also review your use of the gpio library and compare your use case against other reference design projects. You either need to make gpio not require root access, or learn how to migrate xauth credentials to the root user.

Of course what I'd do is simply enable the root user and log in my X11 session as root, much to the shagrin of the kiddies who were brought up believing what their college professors told them: that you should never log in as root.

fcarney

@Kent-Dorfman said in Qt runtime dependency:

enable the root user and log in my X11 session as root

You are a monster!

who were brought up believing what their college professors told them

Yeah, experience after college tends to debunk a lot of sh...er...crap they taught in school.

enjoysmath

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