qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.

austom

Hello guys!
I am a new user of linux. My version of linux is CentOS Linux release 7.3.1611 (Core).The reason for this problem is because I am using a python script (matplotlib) for drawing.

python3.7 ../../scripts/compare_design_to_control.py control.fasc design.fasc

Then it shows :

Got keys from plugin meta data ("xcb")
QFactoryLoader::QFactoryLoader() looking at "/data/home/ldx022/miniconda3/envs/bio/plugins/platforms/libxcb-icccm.so.4"
QElfParser: '/data/home/ldx022/miniconda3/envs/bio/plugins/platforms/libxcb-icccm.so.4' is not an ELF object (file too small)
"'/data/home/ldx022/miniconda3/envs/bio/plugins/platforms/libxcb-icccm.so.4' is not an ELF object (file too small)" 
         not a plugin
QFactoryLoader::QFactoryLoader() checking directory path "/data/home/ldx022/miniconda3/envs/bio/bin/platforms" ...
Cannot load library /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/libqxcb.so: (libxcb-icccm.so.4: cannot open shared object file: No such file or directory)
QLibraryPrivate::loadPlugin failed on "/data/home/ldx022/miniconda3/envs/bio/plugins/platforms/libqxcb.so" : "Cannot load library /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/libqxcb.so: (libxcb-icccm.so.4: cannot open shared object file: No such file or directory)"
qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: eglfs, minimal, minimalegl, offscreen, vnc, webgl, xcb.

Aborted

I looked at lots of solutions to similar problems before asking this question.Unlike in the previous cases, since I am using the research group's server, I cannot use the simplest yum command to install the corresponding dependency libraries because I have no root premission. So I use a number of methods including the use of

rpm2cpio XCB util - wm - 0.4.1-5. El7. Aarch64. RPM | cpio - idvm

this command to the corresponding dependent libraries the installation of RPM package.After that I change the ~.bashrc file in a correct path:

export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/data/home/ldx022/lib/usr/lib64

and use the ldd command it turns out the way doesn't work at all.

(bio) [ldx022@mn01 my_files]$ cd /data/home/ldx022/miniconda3/envs/bio/plugins/platforms
(bio) [ldx022@mn01 platforms]$ ldd libqxcb.so
linux-vdso.so.1 =>  (0x00007ffe6d053000)
	libQt5XcbQpa.so.5 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libQt5XcbQpa.so.5 (0x00007f4865f82000)
	libfontconfig.so.1 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libfontconfig.so.1 (0x00007f4865f34000)
	libfreetype.so.6 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libfreetype.so.6 (0x00007f4865e7b000)
	libz.so.1 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libz.so.1 (0x00007f4865e5d000)
	libQt5Gui.so.5 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libQt5Gui.so.5 (0x00007f48659fa000)
	libQt5DBus.so.5 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libQt5DBus.so.5 (0x00007f4865992000)
	libQt5Core.so.5 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libQt5Core.so.5 (0x00007f4865512000)
	libGL.so.1 => /lib64/libGL.so.1 (0x00007f4865269000)
	libpthread.so.0 => /lib64/libpthread.so.0 (0x00007f486504d000)
	libX11-xcb.so.1 => /lib64/libX11-xcb.so.1 (0x00007f4864e4b000)
	libxcb-icccm.so.4 => not found
	libxcb-image.so.0 => not found
	libxcb-atom.so.1 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libxcb-atom.so.1 (0x00007f4864c45000)
	libxcb-aux.so.0 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libxcb-aux.so.0 (0x00007f4864a40000)
	libxcb-event.so.1 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libxcb-event.so.1 (0x00007f486483b000)
	libxcb-keysyms.so.1 => not found
	libxcb-randr.so.0 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libxcb-randr.so.0 (0x00007f4864827000)
	libxcb-render-util.so.0 => not found
	libxcb-render.so.0 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libxcb-render.so.0 (0x00007f4864817000)
	libxcb-shape.so.0 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libxcb-shape.so.0 (0x00007f4864810000)
	libxcb-sync.so.1 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libxcb-sync.so.1 (0x00007f4864806000)
	libxcb-xfixes.so.0 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libxcb-xfixes.so.0 (0x00007f48647fb000)
	libxcb-xinerama.so.0 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libxcb-xinerama.so.0 (0x00007f48647f4000)
	libxcb-xkb.so.1 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libxcb-xkb.so.1 (0x00007f48647d3000)
	libxcb-xinput.so.0 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libxcb-xinput.so.0 (0x00007f48647ad000)
	libxcb.so.1 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libxcb.so.1 (0x00007f4864780000)
	libxcb-shm.so.0 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libxcb-shm.so.0 (0x00007f486477a000)
	libXext.so.6 => /lib64/libXext.so.6 (0x00007f4864568000)
	libX11.so.6 => /lib64/libX11.so.6 (0x00007f4864229000)
	libSM.so.6 => /lib64/libSM.so.6 (0x00007f4864021000)
	libICE.so.6 => /lib64/libICE.so.6 (0x00007f4863e05000)
	libxkbcommon-x11.so.0 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libxkbcommon-x11.so.0 (0x00007f4863dfa000)
	libxkbcommon.so.0 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libxkbcommon.so.0 (0x00007f4863db7000)
	libdl.so.2 => /lib64/libdl.so.2 (0x00007f4863bb3000)
	libstdc++.so.6 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libstdc++.so.6 (0x00007f486399e000)
	libm.so.6 => /lib64/libm.so.6 (0x00007f486369c000)
	libgcc_s.so.1 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libgcc_s.so.1 (0x00007f4863682000)
	libc.so.6 => /lib64/libc.so.6 (0x00007f48632c0000)
	libxcb-icccm.so.4 => not found
	libxcb-image.so.0 => not found
	libxcb-keysyms.so.1 => not found
	libxcb-render-util.so.0 => not found
	libgthread-2.0.so.0 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/./libgthread-2.0.so.0 (0x00007f48632b9000)
	libglib-2.0.so.0 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/./libglib-2.0.so.0 (0x00007f4863182000)
	libxml2.so.2 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/./libxml2.so.2 (0x00007f4863019000)
	libpng16.so.16 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/./libpng16.so.16 (0x00007f4862fe0000)
	libdbus-1.so.3 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/./libdbus-1.so.3 (0x00007f4862f8a000)
	libicui18n.so.58 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/./libicui18n.so.58 (0x00007f4862d0b000)
	libicuuc.so.58 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/./libicuuc.so.58 (0x00007f4862b57000)
	libicudata.so.58 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/./libicudata.so.58 (0x00007f4861255000)
	libzstd.so.1 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/./libzstd.so.1 (0x00007f4861183000)
	/lib64/ld-linux-x86-64.so.2 (0x00007f4866066000)
	libGLX.so.0 => /lib64/libGLX.so.0 (0x00007f4860f50000)
	libGLdispatch.so.0 => /lib64/libGLdispatch.so.0 (0x00007f4860c9a000)
	libXau.so.6 => /lib64/libXau.so.6 (0x00007f4860a95000)
	libuuid.so.1 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/libuuid.so.1 (0x00007f4860a8c000)
	libpcre.so.1 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/././libpcre.so.1 (0x00007f4860a44000)
	liblzma.so.5 => /data/home/ldx022/miniconda3/envs/bio/plugins/platforms/./../../lib/././liblzma.so.5 (0x00007f4860a1b000)
	librt.so.1 => /lib64/librt.so.1 (0x00007f4860812000)

libxcb-icccm.so.4 still cannot be found.I ran out the ideas of it.Any suggestions would be appreaciated!

SGaist

Hi and welcome to devnet,

Did you check if ˋ/data/home/ldx022/miniconda3/envs/bio/plugins/platforms/libxcb-icccm.so.4ˋ is somehow corrupted as the error message suggests ?

austom

@austom said in qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.:

QFactoryLoader::QFactoryLoader() looking at "/data/home/ldx022/miniconda3/envs/bio/plugins/platforms/libxcb-icccm.so.4"
QElfParser: '/data/home/ldx022/miniconda3/envs/bio/plugins/platforms/libxcb-icccm.so.4' is not an ELF object (file too small)
"'/data/home/ldx022/miniconda3/envs/bio/plugins/platforms/libxcb-icccm.so.4' is not an ELF object (file too small)"
not a plugin

Thank you for your reply.
You mean this section?

I have created a corresponding soft link for libxcb-icccm.so.4 to the corresponding file in the corresponding folder.But it doesn't work at all.

SGaist

You should rather check your conda environment. That library should not be broken inside it.

austom

The environment variables look like this, but I still can't find what went wrong.

SGaist

Not the environment variables, the conda environment content itself.

austom

@SGaist
Sorry I misunderstood.But how to check if there is a problem with the library?

I also created soft links in it.But that doesn't seem to work

SGaist

The main issue from your picture seems that the library seems to be missing. You only have one link and not the final library itself.

austom

@SGaist
I have downloaded the .rpm file and use the following command to install it.

rpm2cpio XCB util - wm - 0.4.1-5. El7. Aarch64. RPM | cpio - idvm

But I didn't instaill it in the conda.Should I install them in the conda environment?

SGaist

Wait, the original error was that there was an issue with the library file. Now you are modifying your system installation while I am suggesting to check the content of your conda environment.

austom

@SGaist
You mean I can't use the soft link instead of original file in the conda environment?

SGaist

No, I mean you should search why your environment was corrupted rather than trying to force it working using libraires from somewhere else.

One simple way would be to create a new environment from scratch to see if you have the same issue.

austom

@SGaist I have created a new conda environment. But the problem remains unresolved.The entire process of creating an environment from scratch is as follows.

SGaist

Please stop installing system packages in your conda environment. The goal of a new environnement is to start debugging your issue from scratch.

So please, create a new environment without installing anything other than conda packages.

alex smith

On Linux, the xcb QPA (Qt Platform Abstraction) platform plugin is used. It provides the basic functionality needed by Qt GUI and Qt Widgets to run against X11. Its library dependencies are described the following table..

Call for Presentations - Qt World Summit

Unsolved qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "" even though it was found.