A method for obtaining the address of a function

[coolxv]

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

int main() {
    // 打开当前可执行文件（假设已使用-rdynamic编译）
    void *handle = dlopen(NULL, RTLD_LAZY);
    if (!handle) {
        fprintf(stderr, "dlopen failed: %s\n", dlerror());
        return 1;
    }

    // 获取函数指针
    void (*hello)() = (void (*)())dlsym(handle, "_Z5hellov");
    const char *dlsym_error = dlerror();
    if (dlsym_error) {
        fprintf(stderr, "dlsym failed: %s\n", dlsym_error);
        dlclose(handle);
        return 1;
    }

    // 调用函数
    hello();

    // 关闭句柄
    dlclose(handle);
    return 0;
}

// 定义一个简单的函数，将被动态加载
void hello() {
    printf("Hello from dynamically loaded code!\n");
}

 g++ -rdynamic -o test test.cpp  -ldl
~$ ./test
Hello from dynamically loaded code!