I am creating an torrent application using libtorrent in VS 2008. I tried the example given in the link http://www.rasterbar.com/products/libtorrent/examples.html
BUt it is showing me these error....how to solve them?
Linking...
main.obj : error LNK2019: unresolved external symbol "public: __thiscall libtorrent::torrent_info::~torrent_info(void)" (??1torrent_info#libtorrent##QAE#XZ) referenced in function _main
main.obj : error LNK2019: unresolved external symbol "public: __thiscall libtorrent::torrent_info::torrent_info(struct libtorrent::lazy_entry const &)" (??0torrent_info#libtorrent##QAE#ABUlazy_entry#1##Z) referenced in function _main
main.obj : error LNK2019: unresolved external symbol "class std::basic_ostream > & __cdecl libtorrent::operator<<(class std::basic_ostream > &,struct libtorrent::lazy_entry const &)" (??6libtorrent##YAAAV?$basic_ostream#DU?$char_traits#D#std###std##AAV12#ABUlazy_entry#0##Z) referenced in function _main
main.obj : error LNK2019: unresolved external symbol "int __cdecl libtorrent::lazy_bdecode(char const *,char const *,struct libtorrent::lazy_entry &,int)" (?lazy_bdecode#libtorrent##YAHPBD0AAUlazy_entry#1#H#Z) referenced in function _main
main.obj : error LNK2019: unresolved external symbol "public: void __thiscall libtorrent::lazy_entry::clear(void)" (?clear#lazy_entry#libtorrent##QAEXXZ) referenced in function "public: __thiscall libtorrent::lazy_entry::~lazy_entry(void)" (??1lazy_entry#libtorrent##QAE#XZ)
main.obj : error LNK2019: unresolved external symbol "void __cdecl libtorrent::to_hex(char const *,int,char *)" (?to_hex#libtorrent##YAXPBDHPAD#Z) referenced in function "class std::basic_ostream > & __cdecl libtorrent::operator<<(class std::basic_ostream > &,class libtorrent::big_number const &)" (??6libtorrent##YAAAV?$basic_ostream#DU?$char_traits#D#std###std##AAV12#ABVbig_number#0##Z)
main.obj : error LNK2019: unresolved external symbol "public: struct libtorrent::peer_request __thiscall libtorrent::file_storage::map_file(int,__int64,int)const " (?map_file#file_storage#libtorrent##QBE?AUpeer_request#2#H_JH#Z) referenced in function "public: struct libtorrent::peer_request __thiscall libtorrent::torrent_info::map_file(int,__int64,int)const " (?map_file#torrent_info#libtorrent##QBE?AUpeer_request#2#H_JH#Z)
C:\Users\photoshop3\Documents\Visual Studio 2008\Projects\Lib2\Debug\Lib2.exe : fatal error LNK1120: 7 unresolved externals
The .lib is not included in your project. Make sure you are linking it in;
Configuration Properties -> Linker -> Input -> Additional Dependencies
Another altnerative is to simply copy the .lib to your project folder but don't, it's bound to create problems later on.
Sometimes the .lib is not shipped with the library, so you need to compile it yourself.
The README will tell you this. If this is the case, they usually ship with a .sln file you can open and the just compile it into a .lib file which you then reference in your main application, as I wrote above
Have you added the path of header files in the "Configuration Properties" --> "C/C++“ --> "General" --> "Additional Include Directories"?
The link gives you only the sources (including headerfiles) of libtorrent. You should compile this sources to get a .lib file. Add this .lib file to your client:
Configuration Properties/Linker/Input -> Additional Dependencies: libtorrent-rasterbar.lib
The best starting point for compiling should be the README file.
public: isn't the unresolved symbol. It's just there because the linker it trying to tell you that (most) of the unresolved symbols are public member functions.
It looks like you've included the header for "libtorrent", but not linked to the "libtorrent" library.
You have probably not linked with the torrent library or specified the wrong path to it so that the linker cannot find it.
If the input libraries are of 32bit and your are using them in building a 64bit it might be one of the reasons
For me, I had it included in my project, but it turned out that it was a plugin that was designed to not create an instance of in my unit test.
Related
I am new in c++ but i need to do a project using opencv.
I have downlaoded opencv-4.5.2 and opencv_contrib and I am using Visual 2019.
I have used cmake and I got no error.
Then in the project I have included, the "C:\opencv\opencv_lib\install\include" directory fot the C++ additional include directories
For the Linker I have included ,"C:\opencv\opencv_lib\install\x64\vc16\lib" for the additional library directories.
I have included, "opencv_core452.lib,opencv_highgui452.lib,opencv_imgcodecs452.lib", int he additional dependacies.
I have included, "C:...opencv\build\x64\vc14\bin" for the path.
When i run a simple project it seems that something goes wrong and I am not sure what it is.
Here are the errors:
Severity Code Description Project File Line Suppression State
Error LNK2019 unresolved external symbol "public: class cv::Mat & __thiscall cv::Mat::operator=(class cv::Mat &&)" (??4Mat#cv##QAEAAV01#$$QAV01##Z) referenced in function _main protorype C:...\protorype.obj 1
Error LNK2019 unresolved external symbol "public: __thiscall cv::Mat::Mat(void)" (??0Mat#cv##QAE#XZ) referenced in function _main protorype C:...\protorype.obj 1
Error LNK2019 unresolved external symbol "public: __thiscall cv::Mat::~Mat(void)" (??1Mat#cv##QAE#XZ) referenced in function _main protorype C:...\protorype.obj 1
Error LNK2019 unresolved external symbol "class cv::Mat __cdecl cv::imread(class std::basic_string<char,struct std::char_traits,class std::allocator > const &,int)" (?imread#cv##YA?AVMat#1#ABV?$basic_string#DU?$char_traits#D#std##V?$allocator#D#2##std##H#Z) referenced in function _main protorype C:...\protorype.obj 1
Error LNK2019 unresolved external symbol "void __cdecl cv::namedWindow(class std::basic_string<char,struct std::char_traits,class std::allocator > const &,int)" (?namedWindow#cv##YAXABV?$basic_string#DU?$char_traits#D#std##V?$allocator#D#2##std##H#Z) referenced in function _main protorype C:...\protorype.obj 1
Error LNK2019 unresolved external symbol "void __cdecl cv::imshow(class std::basic_string<char,struct std::char_traits,class std::allocator > const &,class cv::debug_build_guard::_InputArray const &)" (?imshow#cv##YAXABV?$basic_string#DU?$char_traits#D#std##V?$allocator#D#2##std##ABV_InputArray#debug_build_guard#1##Z) referenced in function _main protorype C:...\protorype.obj 1
Error LNK1120 6 unresolved externals protorype C:...\protorype.exe 1
Because I am new, please explain me in simple words hwo to resolve it.
Thank you in advance!
I finally found it.
I dont know, probably eventhough I was using the right libraries and using the right directories as well, I decided to copy all the libraries into the dependacies and not just those that i use and it workes. Here are all the directories for my case, but note that if you are usign a different version probably they are different.
opencv_aruco452d.lib opencv_barcode452d.lib opencv_bgsegm452d.lib opencv_bioinspired452d.lib opencv_calib3d452d.lib opencv_ccalib452d.lib opencv_core452d.lib opencv_datasets452d.lib opencv_dnn_objdetect452d.lib opencv_dnn_superres452d.lib opencv_dnn452d.lib opencv_dpm452d.lib opencv_face452d.lib opencv_features2d452d.lib opencv_flann452d.lib opencv_fuzzy452d.lib opencv_gapi452d.lib opencv_hdf452d.lib opencv_hfs452d.lib opencv_highgui452d.lib opencv_img_hash452d.lib opencv_imgcodecs452d.lib opencv_imgproc452d.lib opencv_intensity_transform452d.lib opencv_line_descriptor452d.lib opencv_mcc452d.lib opencv_ml452d.lib opencv_objdetect452d.lib opencv_optflow452d.lib opencv_phase_unwrapping452d.lib opencv_photo452d.lib opencv_plot452d.lib opencv_quality452d.lib opencv_rapid452d.lib opencv_reg452d.lib opencv_rgbd452d.lib opencv_saliency452d.lib opencv_shape452d.lib opencv_stereo452d.lib opencv_stitching452d.lib opencv_structured_light452d.lib opencv_superres452d.lib opencv_surface_matching452d.lib opencv_text452d.lib opencv_tracking452d.lib opencv_video452d.lib opencv_videoio452d.lib opencv_videostab452d.lib opencv_wechat_qrcode452d.lib opencv_xfeatures2d452d.lib opencv_ximgproc452d.lib opencv_xobjdetect452d.lib opencv_xphoto452d.lib
I am a newbie to C++. I want to use, lacewing-project.org in my C++ project. I read the documentation on how to build it and successfully did it using both DLL - Release and Static Library - Release configurations.
Now I don't know how to use this in my project and how to setup and configure my project? I was following this tutorial, but was stuck in the middle because of missing options in the latest Visual Studio. I use Visual C++ Expression Ed., 2012 on Windows 8
I googled and did the following:
Added the lib file and the lacewing.h file in my project.
Under Visual C++ Project Properties, in the Linker folder -> Input I added the lib file as Additional Dependencies.
I placed the dll in Windows\System32 folder. Will I need to do anything with the dll other than placing it in win32 folder?
My code is from the hello world example given in the documentation.
When I try to compile I get:
1>------ Build started: Project: test, Configuration: Debug Win32 ------
1> Source.cpp
1>Source.obj : error LNK2019: unresolved external symbol __imp__lw_version referenced in function "void __cdecl on_get(struct lacewing::_webserver *,struct lacewing::_webserver_request *)" (?on_get##YAXPAU_webserver#lacewing##PAU_webserver_request#2##Z)
1>Source.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) void __cdecl lacewing::pump_delete(struct lacewing::_pump *)" (__imp_?pump_delete#lacewing##YAXPAU_pump#1##Z) referenced in function _main
1>Source.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: struct lacewing::_error * __thiscall lacewing::_eventpump::start_eventloop(void)" (__imp_?start_eventloop#_eventpump#lacewing##QAEPAU_error#2#XZ) referenced in function _main
1>Source.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) struct lacewing::_eventpump * __cdecl lacewing::eventpump_new(void)" (__imp_?eventpump_new#lacewing##YAPAU_eventpump#1#XZ) referenced in function _main
1>Source.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: void __cdecl lacewing::_stream::writef(char const *,...)" (__imp_?writef#_stream#lacewing##QAAXPBDZZ) referenced in function "void __cdecl on_get(struct lacewing::_webserver *,struct lacewing::_webserver_request *)" (?on_get##YAXPAU_webserver#lacewing##PAU_webserver_request#2##Z)
1>Source.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: void __thiscall lacewing::_webserver::host(long)" (__imp_?host#_webserver#lacewing##QAEXJ#Z) referenced in function _main
1>Source.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: void __thiscall lacewing::_webserver::on_get(void (__cdecl*)(struct lacewing::_webserver *,struct lacewing::_webserver_request *))" (__imp_?on_get#_webserver#lacewing##QAEXP6AXPAU12#PAU_webserver_request#2##Z#Z) referenced in function _main
1>Source.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) struct lacewing::_webserver * __cdecl lacewing::webserver_new(struct lacewing::_pump *)" (__imp_?webserver_new#lacewing##YAPAU_webserver#1#PAU_pump#1##Z) referenced in function _main
1>Source.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) void __cdecl lacewing::webserver_delete(struct lacewing::_webserver *)" (__imp_?webserver_delete#lacewing##YAXPAU_webserver#1##Z) referenced in function _main
1>C:\Users\Jayarathina\Desktop\New folder (3)\test\Debug\test.exe : fatal error LNK1120: 9 unresolved externals
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========
Please help...
To link statically with the library, one must define lw_import. If you don't do this, it will default to __declspec(dllimport):
#ifndef lw_import
#define lw_import __declspec (dllimport)
#endif
which causes the linker to try and pull the functions in from a DLL (which is wrong when statically linking). To do this, you can either add lw_import= to your preprocessor definitions in the project properties, or #define it before including lacewing.h, as so:
#define lw_import
#include <lacewing.h>
As you're statically linking the library, you will also need to link any library dependencies into your own project. You can find the list in the project properties of liblacewing.vcproj itself, but as of 0.5.1 these are ws2_32.lib, mswsock.lib, mpr.lib, secur32.lib and crypt32.lib.
I have a project that used to compile just fine, using the freetype library.
Since then my OS has been reinstalled and therefore so has Visual Studio 2010.
I have re-included and reinstalled all of the .lib .dll and header files. For some reason now if I run the program with the release configuration it runs just fine. But if I switch over to the debug config, it gives me unresolved external symbol errors from the linker, on the freetype library functions.
Now I'm sure my C++ directories for both configurations are identical as I re-set them using the all-configurations tab in the solution settings. As well as this, so are both configurations "additional directories/additional dependancies settings", set identically in the same way.
The only difference I could find between the release and debug folders in the project folder, is the presence of a file in the debug folder called "vc100.idb", which is a minimum rebuild dependancy file. This looked promising, but removing it yielded no results, so I put it back.
Do you have any ideas of what could be causing this difference between the configurations compiling?
Worst come to worst, I can continue programming on the release config, but I'd rather not continue down this road as I'd really like to know the root of this problem.
Thanks in advance,
Guy
The errors:
1>freetype.obj : error LNK2019: unresolved external symbol _FT_Glyph_To_Bitmap referenced in function "void __cdecl freetype::make_dlist(struct FT_FaceRec_ *,char,unsigned int,unsigned int *)" (?make_dlist#freetype##YAXPAUFT_FaceRec_##DIPAI#Z)
1>freetype.obj : error LNK2019: unresolved external symbol _FT_Get_Glyph referenced in function "void __cdecl freetype::make_dlist(struct FT_FaceRec_ *,char,unsigned int,unsigned int *)" (?make_dlist#freetype##YAXPAUFT_FaceRec_##DIPAI#Z)
1>freetype.obj : error LNK2019: unresolved external symbol _FT_Load_Glyph referenced in function "void __cdecl freetype::make_dlist(struct FT_FaceRec_ *,char,unsigned int,unsigned int *)" (?make_dlist#freetype##YAXPAUFT_FaceRec_##DIPAI#Z)
1>freetype.obj : error LNK2019: unresolved external symbol _FT_Get_Char_Index referenced in function "void __cdecl freetype::make_dlist(struct FT_FaceRec_ *,char,unsigned int,unsigned int *)" (?make_dlist#freetype##YAXPAUFT_FaceRec_##DIPAI#Z)
1>freetype.obj : error LNK2019: unresolved external symbol _FT_Done_FreeType referenced in function "public: void __thiscall freetype::font_data::init(char const *,unsigned int)" (?init#font_data#freetype##QAEXPBDI#Z)
1>freetype.obj : error LNK2019: unresolved external symbol _FT_Done_Face referenced in function "public: void __thiscall freetype::font_data::init(char const *,unsigned int)" (?init#font_data#freetype##QAEXPBDI#Z)
1>freetype.obj : error LNK2019: unresolved external symbol _FT_Set_Char_Size referenced in function "public: void __thiscall freetype::font_data::init(char const *,unsigned int)" (?init#font_data#freetype##QAEXPBDI#Z)
1>freetype.obj : error LNK2019: unresolved external symbol _FT_New_Face referenced in function "public: void __thiscall freetype::font_data::init(char const *,unsigned int)" (?init#font_data#freetype##QAEXPBDI#Z)
1>freetype.obj : error LNK2019: unresolved external symbol _FT_Init_FreeType referenced in function "public: void __thiscall freetype::font_data::init(char const *,unsigned int)" (?init#font_data#freetype##QAEXPBDI#Z)
Edit: OK well this is strange. I've removed ALL of the freetype directory information rom the include and library directory setting in the release config, as well as the additional dependancies. And the released config version still works!
This is leading me to believe there is something missing (vs config-wise) from moving my files over.
I had the same problem.
I solved it by compiling the freetype( freetype-2.5.2\builds\windows\vc2010\freetype.sln ) solution for the x64 platform (or win32 if you use it).
You will get the .libs for this platform.
Since SCons has been deprecated. I used the gyp to generate vs solution.
I did what they told me on the build BuildingWithGYP.
And the v8 project builded ok!
and I got the v8_base.lib but no v8.lib.
And in the hello world project ,get started.I add the lib directory into the add library.
But it linked failed:
Linking...
1>v8test.obj : error LNK2019: unresolved external symbol "public:
__thiscall v8::HandleScope::~HandleScope(void)" (??
1HandleScope#v8##QAE#XZ) referenced in function _main
1>v8test.obj : error LNK2019: unresolved external symbol "public:
__thiscall v8::String::AsciiValue::~AsciiValue(void)" (??
1AsciiValue#String#v8##QAE#XZ) referenced in function _main
1>v8test.obj : error LNK2019: unresolved external symbol "public:
__thiscall v8::String::AsciiValue::AsciiValue(class v8::Handle<class
v8::Value>)" (??0AsciiValue#String#v8##QAE#V?$Handle#VValue#v8###2##Z)
referenced in function _main
1>v8test.obj : error LNK2019: unresolved external symbol "public:
class v8::Local<class v8::Value> __thiscall v8::Script::Run(void)" (?
Run#Script#v8##QAE?AV?$Local#VValue#v8###2#XZ) referenced in function
_main
……
It seems that couldn't find the implement
but i used the dumpbin tool and find the symbol i can find them in the v8_base.lib
I am sure that the library directory is ok!
but i don't know why it couldn't find the implement.
You can add the lib "v8_base.lib" as an additional dependency to fix the problem.
I am coming from Xcode, trying to compile a project in Visual Studio 2010, and I get the following errors:
2>ofxCLeye.obj : error LNK2019: unresolved external symbol "struct _GUID __cdecl CLEyeGetCameraUUID(int)" (?CLEyeGetCameraUUID##YA?AU_GUID##H#Z) referenced in function "public: static int __cdecl ofxCLeye::listDevices(void)" (?listDevices#ofxCLeye##SAHXZ)
2>ofxCLeye.obj : error LNK2019: unresolved external symbol "int __cdecl CLEyeGetCameraCount(void)" (?CLEyeGetCameraCount##YAHXZ) referenced in function "public: static int __cdecl ofxCLeye::listDevices(void)" (?listDevices#ofxCLeye##SAHXZ)
2>ofxCLeye.obj : error LNK2019: unresolved external symbol "bool __cdecl CLEyeCameraGetFrameDimensions(void *,int &,int &)" (?CLEyeCameraGetFrameDimensions##YA_NPAXAAH1#Z) referenced in function "public: void __thiscall ofxCLeye::grabFrame(void)" (?grabFrame#ofxCLeye##QAEXXZ)
2>ofxCLeye.obj : error LNK2019: unresolved external symbol "bool __cdecl CLEyeCameraGetFrame(void *,unsigned char *,int)" (?CLEyeCameraGetFrame##YA_NPAXPAEH#Z) referenced in function "public: void __thiscall ofxCLeye::grabFrame(void)" (?grabFrame#ofxCLeye##QAEXXZ)
2>ofxCLeye.obj : error LNK2019: unresolved external symbol "bool __cdecl CLEyeDestroyCamera(void *)" (?CLEyeDestroyCamera##YA_NPAX#Z) referenced in function "public: virtual void __thiscall ofxCLeye::close(void)" (?close#ofxCLeye##UAEXXZ)
2>ofxCLeye.obj : error LNK2019: unresolved external symbol "bool __cdecl CLEyeCameraStop(void *)" (?CLEyeCameraStop##YA_NPAX#Z) referenced in function "public: virtual void __thiscall ofxCLeye::close(void)" (?close#ofxCLeye##UAEXXZ)
... etc etc...
2>bin\clEye_debug.exe : fatal error LNK1120: 10 unresolved externals
I imagine that the compiler is trying to link CLEyeMulticam.lib but not finding it. I think that I have configured it properly.
Could you point me with the needed steps to include a library in VS2010 ?
Thank you,
marc
Apologies if this is overly pedantic. If this is a pre-built library (not built as part of the project/solution) then make sure you
a) #include the correct header
b) #define any requisite macros
c) speciy additional .lib dependencies as shown below.
You will need to specify a fully qualifed path (d:\src\project\libs\camera.lib) unless the libary file is in the LIB environment variable.
In the Property Pages for your project, navigate to Configuration > Linker > Input and add the lib file to the Additional Dependencies setting. This applies to VC++ 2008, probably likewise to 2010.