c++ - How to use shared libraries in a static library without forcing end-users to link against these? -


let's i'm working on static library foo.a, makes use of function in bar.so.

how build library in such way uses foo.a in project doesn't have explicitly link against bar.so?

what can in libfoo.a make call dlopen dynamically link libbar.so. then, use dlsym locate function want use.

typedef void (*barfunctiontype) (const char *); functiontype barfunction; void initialize_foo_lib () { void *h = dlopen("libbar.so", rtld_lazy); barfunctiontype barfunction = (barfunctiontype) dlsym(h, "barfunction"); // note scary looking cast function pointer. //... rest of code can call barfunction }

libbar.so should c library, or function should extern "c" if c++ library, find function name properly. otherwise need mangle name find function dlsym. can use objdump -t on library check if names in library mangled.

realize there still dependency on libbar.so, baked static library. user of libfoo.a not have add -lbar link line when link in -lfoo.


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