Linux shared library Loading function
Link from: http://www.faqs.org/docs/Linux-mini/C++-dlopen.html
//1. == main.cpp =============================================
// How to build?
// g++ -o main main.cpp -ldl
//=======================================================
#include <iostream>
#include <dlfcn.h>
int main() {
using std::cout;
using std::cerr;
cout << "C++ dlopen demo\n\n";
// open the library
cout << "Opening hello.so...\n";
void* handle = dlopen("./hello.so", RTLD_LAZY);
if (!handle) {
cerr << "Cannot open library: " << dlerror() << '\n';
return 1;
}
// load the symbol
cout << "Loading symbol hello...\n";
typedef void (*hello_t)();
hello_t hello = (hello_t) dlsym(handle, "hello");
if (!hello) {
cerr << "Cannot load symbol 'hello': " << dlerror() <<
'\n';
dlclose(handle);
return 1;
}
// use it to do the calculation
cout << "Calling hello...\n";
hello();
// close the library
cout << "Closing library...\n";
dlclose(handle);
}
// 2=====hello.cpp ========================================
// How to build?
// g++ -c -fPIC hello.cpp
// g++ -shared -o hello.so
-fPIC hello.o
//======================================================
#include <
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