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Strange External Library error

  • Hi Friends

    I have been using a lot of external libraries lately, and i usually dont have a problem working with them. However, I am working with one of the IR camera's SDK and this is the problem I face :

    The library for some reason runs perfectly alright on Microsoft Visual C++ Express Edition 2008, but fails to run on Qt 4.8.4. Both of them uses the same msvc compiler. I have no idea where I am going wrong.

    I get LNK2019 Linker error : Unresolved external symbols

    Please Help

  • Lifetime Qt Champion


    Without more information it's difficult to help, but you seem to have a missing library somewhere, are you sure you are linking all required libraries ?

    Can you show your project file ?

  • I understand what you mean. But I am pretty sure I have added the libraries properly. Here is how my .pro looks


    INCLUDEPATH += "C://Program Files/Xeneth/Sdk/Include"
    DEPENDPATH += "C://-Program Files/Xeneth/Sdk/Include"

    unix|win32: LIBS += -L"C://Program Files/Xeneth/Sdk/Lib" -lxeneth64

    INCLUDEPATH += "C://Program Files/Xeneth/Sdk/Lib"
    DEPENDPATH += "C://Program Files/Xeneth/Sdk/Lib"

  • Lifetime Qt Champion

    From my experience, -L followed by a path with spaces (even quoted) doesn't work on Windows, use the 8.3 name in place of "Program Files" (something like PROGRA~1, you have to check what is correct).

    On a side not, I think you don't want that path for unix, rather:

    @unix: LIBS += -L/path_to_xeneth/lib
    win32: LIBS += -LC:/PROGRA~1/Xeneth/Sdk/lib
    LIBS += -lxeneth64

  • In my case, I'm working with 4 more libraries which are put the same way into my project. I tried the way suggested by you. No change. :(

  • Lifetime Qt Champion

    Did you check the 8.3 name for Program Files ? It might be something else than PROGRA~1

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