qt may fix this problem

Question

Hi there,

I installed pulpo through a symfony bundle and put it under /usr/bin/pulpo.
When I try to run it from there I get:

This application failed to start because it could not find or load the Qt platform plugin "xcb".

Available platform plugins are: xcb. 
Reinstalling the application may fix this problem.

Because I find no further information I am stuck...

Any hint would be helpful

Thanks in advance

Sebastian

Answer 1

It's probably some conflict of libraries in your OS. Pulpo directory contains all required libraries include xcb support.

You have probably installed different version of Qt in your system and this library is wrongly used by Pulpo. Please try to remove LDLIBRARYPATH before executing Puplo.

Comments

Hi there,

I am sorry but there is no QT installed on this system and LDLIBRARYPATH ist empty or not existing.

Tia

Sebastian

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What OS are you using?

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Sorry, initially I added the information but it was lost due to a mistakenly pressed back.

System:
HyperV VM
Debian 8.0 (Jessie) x64

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Debian as same as Ubuntu should work as expected.

Not sure if this is not somehow related to HyperV Vm (is it a Docker or full VM?)

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It is a full VM, created and installed from scratch as a development environment for Symfony

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This is strange. Can you try ldd Pulpo.exe and ldd xcb library? Is there any missing lib ?

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ldd Pulpo
        linux-vdso.so.1 (0x00007ffe79fa8000)
        libboost_iostreams.so.1.57.0 => /usr/bin/pulpo/./libs/libboost_iostreams.so.1.57.0 (0x00007f1219610000)
        libboost_filesystem.so.1.57.0 => /usr/bin/pulpo/./libs/libboost_filesystem.so.1.57.0 (0x00007f12193f0000)
        libboost_system.so.1.57.0 => /usr/bin/pulpo/./libs/libboost_system.so.1.57.0 (0x00007f12191e8000)
        libboost_thread.so.1.57.0 => /usr/bin/pulpo/./libs/libboost_thread.so.1.57.0 (0x00007f1218fc0000)
        libboost_regex.so.1.57.0 => /usr/bin/pulpo/./libs/libboost_regex.so.1.57.0 (0x00007f1218cb0000)
        libboost_chrono.so.1.57.0 => /usr/bin/pulpo/./libs/libboost_chrono.so.1.57.0 (0x00007f1218aa0000)
        libxml2.so.2 => /usr/bin/pulpo/./libs/libxml2.so.2 (0x00007f1218730000)
        libxslt.so.1 => /usr/bin/pulpo/./libs/libxslt.so.1 (0x00007f12184f0000)
        libexslt.so.0 => /usr/bin/pulpo/./libs/libexslt.so.0 (0x00007f12182d8000)
        libcurl.so.4 => /usr/bin/pulpo/./libs/libcurl.so.4 (0x00007f1218070000)
        libQt5PrintSupport.so.5 => /usr/bin/pulpo/./libs/libQt5PrintSupport.so.5 (0x00007f12199e0000)
        libQt5Script.so.5 => /usr/bin/pulpo/./libs/libQt5Script.so.5 (0x00007f1217df0000)
        libQt5Widgets.so.5 => /usr/bin/pulpo/./libs/libQt5Widgets.so.5 (0x00007f12177a8000)
        libQt5Gui.so.5 => /usr/bin/pulpo/./libs/libQt5Gui.so.5 (0x00007f12172e8000)
        libQt5Network.so.5 => /usr/bin/pulpo/./libs/libQt5Network.so.5 (0x00007f1219888000)
        libQt5DBus.so.5 => /usr/bin/pulpo/./libs/libQt5DBus.so.5 (0x00007f1217260000)
        libQt5Core.so.5 => /usr/bin/pulpo/./libs/libQt5Core.so.5 (0x00007f1216c88000)
        libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f1216a68000)
        libstdc++.so.6 => /usr/lib/x86_64-linux-gnu/libstdc++.so.6 (0x00007f1216758000)
        libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f1216450000)
        libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007f1216238000)
        libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f1215e88000)
        libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f1215c80000)
        librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1 (0x00007f1215a78000)
        libz.so.1 => /lib/x86_64-linux-gnu/libz.so.1 (0x00007f1215858000)
        libssl.so.1.0.0 => /usr/bin/pulpo/./libs/./libssl.so.1.0.0 (0x00007f12155e0000)
        libcrypto.so.1.0.0 => /usr/bin/pulpo/./libs/./libcrypto.so.1.0.0 (0x00007f1215180000)
        /lib64/ld-linux-x86-64.so.2 (0x00007f1219828000)

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ldd platforms/libqxcb.so
        linux-vdso.so.1 (0x00007ffe9fae8000)
        libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007efd77718000)
        libX11.so.6 => /usr/lib/x86_64-linux-gnu/libX11.so.6 (0x00007efd773d0000)
        libX11-xcb.so.1 => not found                                                                
        libXi.so.6 => /usr/lib/x86_64-linux-gnu/libXi.so.6 (0x00007efd771c0000)                     
        libxcb.so.1 => /usr/lib/x86_64-linux-gnu/libxcb.so.1 (0x00007efd76f98000)
        libfontconfig.so.1 => /usr/lib/x86_64-linux-gnu/libfontconfig.so.1 (0x00007efd76d58000)
        libfreetype.so.6 => /usr/lib/x86_64-linux-gnu/libfreetype.so.6 (0x00007efd76aa8000)
        libQt5DBus.so.5 => /usr/bin/pulpo/platforms/../libs/libQt5DBus.so.5 (0x00007efd77988000)
        libQt5Gui.so.5 => /usr/bin/pulpo/platforms/../libs/libQt5Gui.so.5 (0x00007efd765e8000)
        libQt5Core.so.5 => /usr/bin/pulpo/platforms/../libs/libQt5Core.so.5 (0x00007efd76010000)
        libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007efd75df0000)
        libstdc++.so.6 => /usr/lib/x86_64-linux-gnu/libstdc++.so.6 (0x00007efd75ae0000)
        libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007efd757d8000)
        libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007efd75428000)
        /lib64/ld-linux-x86-64.so.2 (0x00007efd77920000)
        libXext.so.6 => /usr/lib/x86_64-linux-gnu/libXext.so.6 (0x00007efd75210000)
        libXau.so.6 => /usr/lib/x86_64-linux-gnu/libXau.so.6 (0x00007efd75008000)
        libXdmcp.so.6 => /usr/lib/x86_64-linux-gnu/libXdmcp.so.6 (0x00007efd74e00000)
        libexpat.so.1 => /lib/x86_64-linux-gnu/libexpat.so.1 (0x00007efd74bd0000)
        libz.so.1 => /lib/x86_64-linux-gnu/libz.so.1 (0x00007efd749b0000)
        libpng12.so.0 => /lib/x86_64-linux-gnu/libpng12.so.0 (0x00007efd74788000)
        libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007efd74570000)
        librt.so.1 => /lib/x86_64-linux-gnu/librt.so.1 (0x00007efd74368000)

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It seems to be perfectly ok ;-(.

Unfortunately, I don't know what is wrong there. Paths are exactly the same like on our testing machine where everything works great.

I found this post on SO https://stackoverflow.com/questions/17106315/failed-to-load-platform-plugin-xcb-while-launching-qt5-app-on-linux-without

Can you try to set following

QT_QPA_PLATFORM_PLUGIN_PATH=path/to/plugins
./pulpo

But it's strange that this doesn't work automatically

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Hi there,

I checked the mentioned link and found QTDEBUGPLUGINS=1 which gives me:

Got keys from plugin meta data ("xcb")
loaded library "/usr/bin/pulpo/platforms/libqxcb.so"
QLibraryPrivate::loadPlugin failed on "/usr/bin/pulpo/platforms/libqxcb.so" : "Cannot load library /
usr/bin/pulpo/platforms/libqxcb.so: (libX11-xcb.so.1: Kann die Shared-Object-Datei nicht öffnen: Datei oder Verzeichnis nicht gefunden)"

Obviously libX11-xcb was not found but trying to do apt-get install libX11-xcb gave me "Package can not be found"

UPDATE:
I found that I need to install libX11-xcb1 which worked but now I get "could not connect to display"

UPDATE2:
As far as I understand because my web development machine is just a webserver it will not work there. So I decided to switch to my windows client to run pulpo from there but much to my surprise this is also not working.
Extracting the zip files gives me some files, running the pulpo.exe gives me once again an error about missing plugin "windows". I cannot see a subfolder "platforms" (which is suggested) and also no file qwindows.dll (which would be the "windows" plugin).
Can you please provide the necessary files or a valid download location?

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Hi, it seems that window package is broken. I will pass it to my colleagues to check it.