Compiling on Fedora 10.
I have just started my first qt GUI application. I used all the default settings.
Its just a simple form. It builds OK without any errors. But when I try and run the application. I get the following message:
Starting /home/rob/projects/qt/test1/test1/test1... No protocol specified test1: cannot connect to X server :0.0 Thanks for any advice,
The general causes for this are as follows:
DISPLAY not set in the environment.
Solution:
export DISPLAY=:0.0 ./myQtCmdHere ( This one doesn't appear to be the one at fault though, as its saying which X display its trying to connect to. Also, its not always 0.0, but most of the time it is )
Non-Authorised User trying to run the X Application
Solution ( as X owning user, ie: yourself )
xhost +local:root # where root is the local user you want to grant access to. Also, if you'd like your X server to be able to receive connection over TCP, these days you must almost always explicitly enable this. To test whether you're server is allowing remote TCP connections try:
telnet 127.0.0.1 6000
If telnet is able to connect, then your X server is listening. If it can't, then neither will any remote X application and you need to enable remote TCP connections on your server.
Adding to above answers. I was in a similar situation while running tests for Code2Pdf at travis. I solved the problem using xvfb-run. Quoting from the manpage,
xvfb-run is a wrapper for the Xvfb(1x) command which simplifies the task of running commands (typically an X client, or a script containing a list of clients to be run) within a virtual X server environment.
The script that I wrote was:
check_install_xvfb() { # check and install xvfb if hash xvfb-run 2>/dev/null; then : else sudo apt-get update sudo apt-get upgrade sudo apt-get install xvfb fi } check_install_xvfb export DISPLAY=localhost:1.0 xvfb-run -a bash .misc/tests.sh # .misc/tests.sh is script that runs unit tests. You can replace it with something suitable to you. Please bear with my bash code style. I am a noob bash programmer.
Running the above script helped me. You can see the failing build and passing build.
Hope it helps