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I'm trying to compile the following simple DL library example code from Program-Library-HOWTO with g++. This is just an example so I can learn how to use and write shared libraries. The real code for the library I'm developing will be written in C++. #include <stdlib.h> #include <stdio.h> #include <dlfcn.h> int main(int argc, char **argv) { void *handle; double (*cosine)(double); char *error; handle = dlopen ("/lib/libm.so.6", RTLD_LAZY); if (!handle) { fputs (dlerror(), stderr); exit(1); } cosine = dlsym(handle, "cos"); if ((error = dlerror()) != NULL) { fputs(error, stderr); exit(1); } printf ("%f\n", (*cosine)(2.0)); dlclose(handle); } If I compile the program with gcc it works fine. gcc -o foo foo.c -ldl When I change the filename and compiler to the following g++ -o foo foo.cpp -ldl I get the following error: foo.cpp:16: error: invalid conversion from 'void*' to 'double (*)(double)' I understand (I think I understand, correct me if this is wrong) that I can't do an implicit cast from a void pointer in C++, but C lets me, and this is why the above code will compile using gcc but not using g++. So I tried an explicit cast by changing line 16 above to: cosine = (double *)dlsym(handle, "cos"); With this in place, I get the following error: foo.cpp:16: error: cannot convert 'double*' to 'double (*)(double)' in assignment These problems probably have more to do with my own general ignorance of proper C++ coding standards than anything else. Can anyone point me to a good tutorial on developing dynamic libraries for Linux that uses C++ example

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