i am trying to execute a simple qt5 c++ program to get all wifi networks listed, when i execute it in linux mint it works out of the box, but when i try to execute it in Raspberry pi (latest raspbian) i get the following error:
QDBusConnection: error: could not send message to service "org.freedesktop.NetworkManager" path "" interface "org.freedesktop.DBus.Introspectable" member "Introspect":
ERROR : Interface invalid
My wifi dongle is working because i can list all wifi networks with this command:
sudo iwlist wlan0 scan
What is happening?
Thanks in advance.
Ups, networkmanager was not installed in Raspberry Pi: sudo apt-get install network-manager
Related
I'm trying to run a Qt d-bus example (chat) on Windows. It compiles fine but I get this error:
Cannot connect to the D-Bus session bus. Please check your system
settings and try again. QEventDispatcherWin32::wakeUp: Failed to post
a message
I installed D-Bus on Windows through a ready made installer found in Google archives.
Can someone give me an idea how to run dbus-daemon on Windows?
I am a beginner, installed ROS Melodic on GCP Ubuntu 18.04 and trying to run the below
"rosrun turtlesim turtlesim_node"
Got the following error :
qt.qpa.screen: QXcbConnection: Could not connect to display
Could not connect to any X display.
Please help
From the error message it is showing, it looks like you need to setup an X-Window environment. You can do so by following the Google Cloud Documentation [1].
Also ensure the application that you are running is having all dependencies satisfied.
[1] https://cloud.google.com/solutions/chrome-desktop-remote-on-compute-engine
I am connecting my windows 7 computer to a linux based cluster using cygwin. Within a specific node in the cluster I want to launch the anaconda spyder gui.
to launch spyder you simply type:
spyder into cygwin
but that returns:
QXcbConnection: Could not connect to display
Aborted (core dumped)
I also tried:
QTA_QPA_PLATFORM=offscreen spyder
but that returns:
QFontDatabase: Cannot find font directory /home/spotter/anaconda2/lib/fonts - is Qt installed correctly?
I installed qt4 dev-tools but it didn't change anything
EDIT:
I installed xinit and xorg and now I try this:
before logging in with ssh i run:
export DISPLAY=localhost:0.0
then I login using ssh:
ssh -Y -X usrname#machine
and now when I try to use spyder I get:
connect localhost port 6000: Connection refused
QXcbConnection: Could not connect to display localhost:11.0
So it sounds like you are running Cygwin on your local Windows machine, logging into a remote server with ssh, and running spyder from that machine with the intent of having it show up on your local screen. Now that you have startx working, you are close to a solution.
Between steps 5 and 6, you need to run the export DISPLAY command on the remote machine and set it to the name of your local computer. You will need to know your hostname for this. The steps will look like this:
startx
ssh -Y -X username#machine
export DISPLAY=win-machine-name:0.0
spyder
The last two commands are executed on the remote machine. I just made up the win-machine-name. In its place, you will put the IP address or machine name of your windows machine. That is how you tell set the DISPLAY environment variable on the remote machine, so X clients know where to send the graphics commands.
Hope this helps!
For me what I did was:
Install packages associated with startx
Change the sshd_config file to allow X11 forwarding
export DISPLAY=localhost:0.0
startx
login with ssh -Y -X username#machine
spyder
I followed the steps below, but I'm getting an error.
Install Virtual Box (version 5.0.0) running on Windows 7 host machine.
Install Ubuntu server version 14.04.02 on it.
git clone https://github.com/openstack-dev/devstack.git
cd devstack; cp samples/local.conf .
After that i ran ./stack.sh but came with this error after running for approx 30 minutes:
2015-07-21 20:04:18.841 | ERROR (ConnectionRefused): Unable to establish connection to 10.0.2.15:8774/v2/c199aa06389a4c8c85dffddad18fce1b/flavors/… 2015-07-21 20:04:20.433 | + exit 1 deb#Devstack:~/devstack$
Please help me in resolving the issue
Try re-running the stack. Thats the best hack i found for DevStack debugging.
You need to do some specific network settings in virtual box to overcome this error.
From the Network section, change Attached to to Bridged Adapter, Adapter Type to Paravirtualized Network (virtio-net) and Promiscuous Mode to Allow All.
Check Enable Nested VT-x/AMD-v from System > Processor .
Select USB Tablet as the Pointing Device from System > Motherboard.
Then restart the virtual machine and check ifconfig for a new IP, add it in local.conf and then try install script again.
It should work this time :-)
I'm running virtualbox 4.1 on Debian. If I try to start a VM with a bridged NIC I get this error:
error: Failed to open/create
the internal network 'HostInterfaceNetworking-eth0' (you might need to
modprobe vboxnetflt to make it accessible) (VERR_PERMISSION_DENIED).
VBoxManage: error: Failed to attach the network LUN
(VERR_PERMISSION_DENIED) VBoxManage: error: Details: code
NS_ERROR_FAILURE (0x80004005), component Console, interface IConsole,
callee
System: Linux localhost.localdomain 3.2.0-4-amd64 #1 SMP Debian 3.2.54-2 x86_64 GNU/Linux
Virtual Box Version: 4.1.18_Debianr78361
The VM starts with a NAT NIC config.
The weirdest thing is if I export this VM and import it to another user, it works. The other user I tested with was the user I usually use for running auto started virtual machines. But I cant remember doing anything special setting this user up. It is only in its own group and no others. I tried to create a new user and import the VM, but I get the same error as above. I've tried purging virtual box, and completely deleting my conf but it does not work. I just cant figure out what the diff is.
Any help appreciated.
The solution for me was to install virtualbox-4.0 from linux mint. I believe that is actually a downgrade from what in debians repos. Probably packaged different too. Still don't know how the heck I was getting the error I was getting...
sudo apt-get install -f virtualbox-4.0
sudo /etc/init.d/vboxdrv setup