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Error while running the Qt program on linux

  • Hi guys,
    I'm getting this error :

    /home/pratip/Downloads/crossCMac/crossCMac/oscilloscope: error while loading shared libraries: libqwt.so.6: cannot open shared object file: No such file or directory

    while running the qwt example which was created on Qt mac os and again compiled on the Qt linux.

    after I got know this error I did try

    sudo updatedb
    locate libqwt //library location was exist.
    sudo ln -s new/path  duplicate/path/libqwt 

    app not running please help me .

  • @thippu
    Running ldd /home/pratip/Downloads/crossCMac/crossCMac/oscilloscope will show you what shared libraries are missing. Doubtless that will show libqwt.so.6. You need to put that in the right place. It's impossible to know whether your "censored" sudo ln -s new/path duplicate/path/libqwt is doing the right thing.

    Furthermore, even if it does find libqwt.so.6, it is my experience that if that in turn requires another ....so library file which is not found, Linux will report the error against against the top-level libqwt.so.6 it was seeking when really it should be against the secondary .so file which that wants. So again use ldd against wherever you have put the libqwt.so.6 it finds and see what that outputs.

  • @JonB I was running this app in release mode.

  • @JonB okay, I'll show you the output after doing the




  • @thippu
    I did do like this:

    pratip@debian:/usr/local/qwt-6.1.3/lib$ ldd /usr/local/qwt-6.1.3/lib 

    output was:

    ldd: /usr/local/qwt-6.1.3/lib$: not regular file

  • @thippu
    Please take the time to at least go man ldd before you ask! Does ldd say anywhere it accepts a directory? No? Hence your error message.

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