test load udf so

dlopen_test.cc

#include <dlfcn.h>
#include <stdio.h>

int main(void) {
    void *handle;
    char *error;

    handle = dlopen("libtest_udf.so", RTLD_LAZY);
    if (!handle) {
        fprintf(stderr, "%s\n", dlerror());
        return 1;
    }

    dlclose(handle);
    return 0;
}

test way
g++ dlopen_test.cc -ldl
LD_LIBRARY_PATH=$(pwd) ./a.out