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building opencvjs but install videoio failed

Hi, I am using docker(ubuntu 16.04) to build opencvjs. My opencv version is 4.4.0 and the emscripten version is latest. I can build opencvjs successfully but if I go into build_js directory and use 'make install',the following warning occured: /videoio/src/backend plugin.cpp:76:30: warning: unused parameter 'h'. And it will give error like following : non-void function does not return a value . I find the code is following: void* getSymbol_(LibHandle_t h, const char* symbolName) {

if defined(_WIN32)

return (void*)GetProcAddress(h, symbolName);

elif defined(__linux__) || defined(__APPLE__) || defined(__OpenBSD__) || defined(__FreeBSD__) || defined(__GLIBC__)

return dlsym(h, symbolName);

endif

} But if I change elif to else(because i am using ubuntu), the error changes into:error: use of undeclared identifier 'dlsym'. Anywhere I can edit to link the dlsym?

click to hide/show revision 2
None

updated 2020-06-24 03:56:00 -0600

berak gravatar image

building opencvjs but install videoio failed

Hi, I am using docker(ubuntu 16.04) to build opencvjs. My opencv version is 4.4.0 and the emscripten version is latest. I can build opencvjs successfully but if I go into build_js directory and use 'make install',the following warning occured: occured:

/videoio/src/backend plugin.cpp:76:30: warning: unused parameter 'h'. 'h'.

And it will give error like following : non-void function does not return a value . I find the code is following: following:

void* getSymbol_(LibHandle_t h, const char* symbolName)
{
 
if defined(_WIN32)
 
{
#if defined(_WIN32)
    return (void*)GetProcAddress(h, symbolName);

 
elif #elif defined(__linux__) || defined(__APPLE__) || defined(__OpenBSD__) || defined(__FreeBSD__) || defined(__GLIBC__)
 
defined(__GLIBC__)
    return dlsym(h, symbolName);
#endif
}

 
endif
 
}
But if I change elif to else(because i am using ubuntu), the error changes into:error: use of undeclared identifier 'dlsym'.
Anywhere I can edit to link the dlsym?  dlsym?

building opencvjs but install videoio failed

Hi, I am using docker(ubuntu 16.04) to build opencvjs. My opencv version is 4.4.0 and the emscripten version is latest. I can build opencvjs successfully but if I go into build_js directory and use 'make install',the following warning occured:

occured:
/videoio/src/backend plugin.cpp:76:30: warning: unused parameter 'h'.

'h'. And it will give error like following : non-void function does not return a value . I find the code is following:

following:
 void* getSymbol_(LibHandle_t h, const char* symbolName)
{
#if if defined(_WIN32)
    return (void*)GetProcAddress(h, symbolName);
#elif elif defined(__linux__) || defined(__APPLE__) || defined(__OpenBSD__) || defined(__FreeBSD__) || defined(__GLIBC__)
    return dlsym(h, symbolName);
#endif
}
endif
}

But if I change elif to else(because i am using ubuntu), the error changes into:error: use of undeclared identifier 'dlsym'. Anywhere I can edit to link the dlsym?

click to hide/show revision 4
None

updated 2020-06-24 04:53:52 -0600

supra56 gravatar image

building opencvjs but install videoio failed

Hi, I am using docker(ubuntu 16.04) to build opencvjs. My opencv version is 4.4.0 and the emscripten version is latest. I can build opencvjs successfully but if I go into build_js directory and use 'make install',the following warning occured: /videoio/src/backend plugin.cpp:76:30: warning: unused parameter 'h'. And it will give error like following : non-void function does not return a value . I find the code is following: following:

 void* `void* getSymbol_(LibHandle_t h, const char* symbolName)
{
if defined(_WIN32)
    return (void*)GetProcAddress(h, symbolName);
elif defined(__linux__) || defined(__APPLE__) || defined(__OpenBSD__) || defined(__FreeBSD__) || defined(__GLIBC__)
    return dlsym(h, symbolName);
endif
}}`

But if I change elif to else(because i am using ubuntu), the error changes into:error: use of undeclared identifier 'dlsym'. Anywhere I can edit to link the dlsym?

click to hide/show revision 5
None

updated 2020-06-24 04:55:38 -0600

berak gravatar image

building opencvjs but install videoio failed

Hi, I am using docker(ubuntu 16.04) to build opencvjs. My opencv version is 4.4.0 and the emscripten version is latest. I can build opencvjs successfully but if I go into build_js directory and use 'make install',the following warning occured: /videoio/src/backend plugin.cpp:76:30: warning: unused parameter 'h'. And it will give error like following : non-void function does not return a value . I find the code is following:

 `void* void* getSymbol_(LibHandle_t h, const char* symbolName)
{
if defined(_WIN32)
    return (void*)GetProcAddress(h, symbolName);
elif defined(__linux__) || defined(__APPLE__) || defined(__OpenBSD__) || defined(__FreeBSD__) || defined(__GLIBC__)
    return dlsym(h, symbolName);
endif
}`
}

But if I change elif to else(because i am using ubuntu), the error changes into:error: use of undeclared identifier 'dlsym'. Anywhere I can edit to link the dlsym?