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  4. how to fix " Missing argument to '-L' " error ?
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how to fix " Missing argument to '-L' " error ?

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  • EddyE Eddy

    Good to see it's funny to you ;-)

    Can you edit the link to you image or just copy the text here? We cannot see the image in your previous post.
    You can use an image provider to show it to us by following this topic
    There is still a problem with the uploading of image in the Qt forum. The admins are working on it though.

    Edit : did you check the hint from @koahnig ?

    AhtiA Offline
    AhtiA Offline
    Ahti
    wrote on last edited by Ahti
    #11

    @Eddy see i edited the post

    changing from && to $$ ? yes i did that but now i am gettings those errors

    note the problem is with those Dll files i know it because when i delete them and run my project it works.

    what is a signature ?? Lol

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    • EddyE Offline
      EddyE Offline
      Eddy
      wrote on last edited by
      #12

      why do you have those 2 lines?

      win32:CONFIG(release,debug|release): LIBS += -L$$PWD/Dll/ -ldxva2
      win32:CONFIG(release,debug|release): LIBS += -L$$PWD/Library/ -ldxva2
      

      Is one of them not enough?
      The Dll path seems redundant since you don't use it further on

      Qt Certified Specialist
      www.edalsolutions.be

      AhtiA 1 Reply Last reply
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      • EddyE Eddy

        why do you have those 2 lines?

        win32:CONFIG(release,debug|release): LIBS += -L$$PWD/Dll/ -ldxva2
        win32:CONFIG(release,debug|release): LIBS += -L$$PWD/Library/ -ldxva2
        

        Is one of them not enough?
        The Dll path seems redundant since you don't use it further on

        AhtiA Offline
        AhtiA Offline
        Ahti
        wrote on last edited by Ahti
        #13

        @Eddy

        Okay removed everything except :

        win32:CONFIG(release,debug|release): LIBS += -L$$PWD/Dll/ -ldxva2
        

        but still getting those 3 errors

        I use that Dll file for getting some windows functions that i need in my project.
        functions like :
        GetDesktopWindow();
        MonitorFromWIndow();
        GetCurrentBrightness();
        etc

        what is a signature ?? Lol

        K 1 Reply Last reply
        0
        • EddyE Offline
          EddyE Offline
          Eddy
          wrote on last edited by
          #14

          what is in your $$PWD/Dll/ folder?

          Qt Certified Specialist
          www.edalsolutions.be

          AhtiA 1 Reply Last reply
          1
          • AhtiA Ahti

            @Eddy

            Okay removed everything except :

            win32:CONFIG(release,debug|release): LIBS += -L$$PWD/Dll/ -ldxva2
            

            but still getting those 3 errors

            I use that Dll file for getting some windows functions that i need in my project.
            functions like :
            GetDesktopWindow();
            MonitorFromWIndow();
            GetCurrentBrightness();
            etc

            K Offline
            K Offline
            koahnig
            wrote on last edited by
            #15

            @Ahti said in how to fix " Missing argument to '-L' " error ?:

            @Eddy

            Okay removed everything except :

            win32:CONFIG(release,debug|release): LIBS += -L$$PWD/Dll/ -ldxva2
            

            but still getting those 3 errors

            I use that Dll file for getting some windows functions that i need in my project.
            functions like :
            GetDesktopWindow();
            MonitorFromWIndow();
            GetCurrentBrightness();
            etc

            The problem ist that this is only working for release. Therefore, you need to be sure that you are in release mode.
            Also sometimes it is good to rerun qmake and possibly rebuild your libraries.

            Vote the answer(s) that helped you to solve your issue(s)

            1 Reply Last reply
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            • EddyE Eddy

              what is in your $$PWD/Dll/ folder?

              AhtiA Offline
              AhtiA Offline
              Ahti
              wrote on last edited by
              #16

              @Eddy

              3 windows dll files

              dxva2.dll, dxva264.dll and user32.dll

              what is a signature ?? Lol

              K 1 Reply Last reply
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              • AhtiA Ahti

                @Eddy

                3 windows dll files

                dxva2.dll, dxva264.dll and user32.dll

                K Offline
                K Offline
                koahnig
                wrote on last edited by
                #17

                @Ahti said in how to fix " Missing argument to '-L' " error ?:

                @Eddy

                3 windows dll files

                dxva2.dll, dxva264.dll and user32.dll

                no libs with those file names?
                The dlls are used during run time, but while linking you need to have the libs created together with the dlls there.

                Vote the answer(s) that helped you to solve your issue(s)

                AhtiA 1 Reply Last reply
                0
                • K koahnig

                  @Ahti said in how to fix " Missing argument to '-L' " error ?:

                  @Eddy

                  3 windows dll files

                  dxva2.dll, dxva264.dll and user32.dll

                  no libs with those file names?
                  The dlls are used during run time, but while linking you need to have the libs created together with the dlls there.

                  AhtiA Offline
                  AhtiA Offline
                  Ahti
                  wrote on last edited by
                  #18

                  @koahnig

                  now i got the libs but still getting that error :(

                  what is a signature ?? Lol

                  K 1 Reply Last reply
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                  • AhtiA Ahti

                    @koahnig

                    now i got the libs but still getting that error :(

                    K Offline
                    K Offline
                    koahnig
                    wrote on last edited by
                    #19

                    @Ahti said in how to fix " Missing argument to '-L' " error ?:

                    @koahnig

                    now i got the libs but still getting that error :(

                    What is the actual error message with your current configuration?
                    Probably it would be good also to post the current .pro file.

                    Vote the answer(s) that helped you to solve your issue(s)

                    AhtiA 1 Reply Last reply
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                    • K koahnig

                      @Ahti said in how to fix " Missing argument to '-L' " error ?:

                      @koahnig

                      now i got the libs but still getting that error :(

                      What is the actual error message with your current configuration?
                      Probably it would be good also to post the current .pro file.

                      AhtiA Offline
                      AhtiA Offline
                      Ahti
                      wrote on last edited by
                      #20

                      @koahnig

                      those three errors that i already mentioned.

                      my new pro file:

                      #-------------------------------------------------
                      #
                      # Project created by Ahtisham 2016-08-16T13:18:59
                      #
                      #-------------------------------------------------
                      
                      QT       += core gui
                      
                      greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
                      
                      TARGET = testMyProject
                      TEMPLATE = app
                      
                      
                      SOURCES += main.cpp\
                              eyecare.cpp \
                          others.cpp
                      
                      HEADERS  += eyecare.h \
                          others.h
                      
                      FORMS    += eyecare.ui
                      
                      RESOURCES += \
                          images.qrc
                      
                      
                      win32:CONFIG(release,debug|release): LIBS += -L$$PWD/Dll/ -ldxva2
                      win32:CONFIG(release,debug|release): LIBS += -L$$PWD/Library/ -ldxva2
                      else:win32:CONFIG(debug,debug|release): LIBS += -L$$PWD/Library/ -ldxva2
                      else:unix: LIBS += -L$$PWD/Library/ -ldxva2
                      
                      INCLUDEPATH += $$PWD/Library
                      DEPENDPATH += $$PWD/Library
                      
                      win32:CONFIG(release, debug|release): LIBS += -L$$PWD/Library/ -luser32
                      else:win32:CONFIG(debug, debug|release): LIBS += -L$$PWD/Library/ -luser32
                      else:unix: LIBS += -L$$PWD/Library/ -luser32
                      
                      INCLUDEPATH += $$PWD/Library
                      DEPENDPATH += $$PWD/Library
                      
                      DISTFILES +=
                      
                      

                      what is a signature ?? Lol

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                      • AhtiA Ahti

                        @koahnig

                        those three errors that i already mentioned.

                        my new pro file:

                        #-------------------------------------------------
                        #
                        # Project created by Ahtisham 2016-08-16T13:18:59
                        #
                        #-------------------------------------------------
                        
                        QT       += core gui
                        
                        greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
                        
                        TARGET = testMyProject
                        TEMPLATE = app
                        
                        
                        SOURCES += main.cpp\
                                eyecare.cpp \
                            others.cpp
                        
                        HEADERS  += eyecare.h \
                            others.h
                        
                        FORMS    += eyecare.ui
                        
                        RESOURCES += \
                            images.qrc
                        
                        
                        win32:CONFIG(release,debug|release): LIBS += -L$$PWD/Dll/ -ldxva2
                        win32:CONFIG(release,debug|release): LIBS += -L$$PWD/Library/ -ldxva2
                        else:win32:CONFIG(debug,debug|release): LIBS += -L$$PWD/Library/ -ldxva2
                        else:unix: LIBS += -L$$PWD/Library/ -ldxva2
                        
                        INCLUDEPATH += $$PWD/Library
                        DEPENDPATH += $$PWD/Library
                        
                        win32:CONFIG(release, debug|release): LIBS += -L$$PWD/Library/ -luser32
                        else:win32:CONFIG(debug, debug|release): LIBS += -L$$PWD/Library/ -luser32
                        else:unix: LIBS += -L$$PWD/Library/ -luser32
                        
                        INCLUDEPATH += $$PWD/Library
                        DEPENDPATH += $$PWD/Library
                        
                        DISTFILES +=
                        
                        
                        K Offline
                        K Offline
                        koahnig
                        wrote on last edited by
                        #21

                        @Ahti

                        Which means that the stubs in the lib-file are missing?
                        Do you have the import and export keyword handled correctly?

                        The dll and the stub-lib are generĂ¢ted with the same tool chain?

                        Vote the answer(s) that helped you to solve your issue(s)

                        AhtiA 1 Reply Last reply
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                        • K koahnig

                          @Ahti

                          Which means that the stubs in the lib-file are missing?
                          Do you have the import and export keyword handled correctly?

                          The dll and the stub-lib are generĂ¢ted with the same tool chain?

                          AhtiA Offline
                          AhtiA Offline
                          Ahti
                          wrote on last edited by Ahti
                          #22

                          @koahnig what do you mean by "stubs in the lib-file" what is that ? i don't know anything about that. I just copied all the required dll and lib files from the system32 to Dll and Library folders of my project respectively. And what is import and export keyword ?

                          I am creating this app just to let user change screen brightness and for that i need to use windows API and that is why i need those dll and lib files.

                          have a look:

                          https://msdn.microsoft.com/en-us/library/windows/desktop/dd692939(v=vs.85).aspx

                          goto the link and see at the end in "Requirements" heading it clearly mentions which library and dll files you need to include in order to use that specific windows api function.

                          what is a signature ?? Lol

                          K 1 Reply Last reply
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                          • AhtiA Ahti

                            @koahnig what do you mean by "stubs in the lib-file" what is that ? i don't know anything about that. I just copied all the required dll and lib files from the system32 to Dll and Library folders of my project respectively. And what is import and export keyword ?

                            I am creating this app just to let user change screen brightness and for that i need to use windows API and that is why i need those dll and lib files.

                            have a look:

                            https://msdn.microsoft.com/en-us/library/windows/desktop/dd692939(v=vs.85).aspx

                            goto the link and see at the end in "Requirements" heading it clearly mentions which library and dll files you need to include in order to use that specific windows api function.

                            K Offline
                            K Offline
                            koahnig
                            wrote on last edited by
                            #23

                            @Ahti

                            When creating a dll you will also create a library (it may have .lib as extension or .a depending on compiler). You need to link the library to your application which is using your dll. The library contains basically a reduced, short part (stub as the rest of tree when you have cut it down) .

                            dllimport and dllexport it is called for MS compilers. An inpedendent way is with Q_DECL_IMPORT and Q_DECL_EXPORT

                            What compiler are you using for creating your application?

                            Vote the answer(s) that helped you to solve your issue(s)

                            AhtiA 1 Reply Last reply
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                            • K koahnig

                              @Ahti

                              When creating a dll you will also create a library (it may have .lib as extension or .a depending on compiler). You need to link the library to your application which is using your dll. The library contains basically a reduced, short part (stub as the rest of tree when you have cut it down) .

                              dllimport and dllexport it is called for MS compilers. An inpedendent way is with Q_DECL_IMPORT and Q_DECL_EXPORT

                              What compiler are you using for creating your application?

                              AhtiA Offline
                              AhtiA Offline
                              Ahti
                              wrote on last edited by
                              #24

                              @koahnig

                              there you go:

                              https://ibb.co/bDcoXk

                              what is a signature ?? Lol

                              K 1 Reply Last reply
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                              • AhtiA Ahti

                                @koahnig

                                there you go:

                                https://ibb.co/bDcoXk

                                K Offline
                                K Offline
                                koahnig
                                wrote on last edited by
                                #25

                                @Ahti

                                From where did you get the include file HighLevelMonitorConfigurationAPI.h ?

                                Vote the answer(s) that helped you to solve your issue(s)

                                AhtiA 1 Reply Last reply
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                                • K koahnig

                                  @Ahti

                                  From where did you get the include file HighLevelMonitorConfigurationAPI.h ?

                                  AhtiA Offline
                                  AhtiA Offline
                                  Ahti
                                  wrote on last edited by Ahti
                                  #26

                                  @koahnig I didn't get it from anywhere i just included it and qt responded on its own by mentioning it in the suggestion list. write this in your qt creator and it will give you a header file with this suggestion:

                                  #include <highlevelmonitorconfigurationapi.h>
                                  

                                  what is a signature ?? Lol

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                                  • AhtiA Ahti

                                    @koahnig I didn't get it from anywhere i just included it and qt responded on its own by mentioning it in the suggestion list. write this in your qt creator and it will give you a header file with this suggestion:

                                    #include <highlevelmonitorconfigurationapi.h>
                                    
                                    K Offline
                                    K Offline
                                    koahnig
                                    wrote on last edited by
                                    #27

                                    @Ahti

                                    I got it. Never used it.

                                    You are using a MinGW-C++ Gnu-compiler together with a MS library and dll.
                                    I think in general this should be possible as long as the keywords are set properly which I would assume for this header file which is apparently part of MinGW.

                                    Once again, please post the error output as to be found in your output pane. They may hold a clue of the problem.

                                    BTW MS compilers are typically not compatible between its different version and certainly not with MinGW in general.

                                    Vote the answer(s) that helped you to solve your issue(s)

                                    AhtiA 1 Reply Last reply
                                    2
                                    • K koahnig

                                      @Ahti

                                      I got it. Never used it.

                                      You are using a MinGW-C++ Gnu-compiler together with a MS library and dll.
                                      I think in general this should be possible as long as the keywords are set properly which I would assume for this header file which is apparently part of MinGW.

                                      Once again, please post the error output as to be found in your output pane. They may hold a clue of the problem.

                                      BTW MS compilers are typically not compatible between its different version and certainly not with MinGW in general.

                                      AhtiA Offline
                                      AhtiA Offline
                                      Ahti
                                      wrote on last edited by Ahti
                                      #28

                                      @koahnig

                                      Here is the error output:
                                      0_1498227345255_eyecare.h - testMyProject - Qt Creator 23-06-2017 19_44_39.png

                                      what is a signature ?? Lol

                                      K 1 Reply Last reply
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                                      • AhtiA Ahti

                                        @koahnig

                                        Here is the error output:
                                        0_1498227345255_eyecare.h - testMyProject - Qt Creator 23-06-2017 19_44_39.png

                                        K Offline
                                        K Offline
                                        koahnig
                                        wrote on last edited by
                                        #29

                                        @Ahti

                                        Need to copy and paste the content of the "Compile Output" pane. This is only a comprehesive summary telling almost nothing.

                                        In the Compile Output pane you have the complete messages from the compile and linker. Typically you have black and blue fonts. When you have errors it starts at certain point to output with red font. There is typically the interesting part.

                                        Not sure if I can see anything, but it is the next best option.

                                        Mark the text where the problem starts plus a couple of lines before and after and with copy and paste post it here as source code. This shold be enough.

                                        Vote the answer(s) that helped you to solve your issue(s)

                                        AhtiA 1 Reply Last reply
                                        0
                                        • K koahnig

                                          @Ahti

                                          Need to copy and paste the content of the "Compile Output" pane. This is only a comprehesive summary telling almost nothing.

                                          In the Compile Output pane you have the complete messages from the compile and linker. Typically you have black and blue fonts. When you have errors it starts at certain point to output with red font. There is typically the interesting part.

                                          Not sure if I can see anything, but it is the next best option.

                                          Mark the text where the problem starts plus a couple of lines before and after and with copy and paste post it here as source code. This shold be enough.

                                          AhtiA Offline
                                          AhtiA Offline
                                          Ahti
                                          wrote on last edited by
                                          #30

                                          @koahnig

                                          Compile Output:

                                          0_1498238168735_library error.JPG

                                          what is a signature ?? Lol

                                          K 1 Reply Last reply
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