linux用c++调用动态库

1.4 用c++动态方式调用动态库libsthc.so：

/*cppdltest.cpp*/

#include "stdio.h"

#include "stdlib.h"

#include "dlfcn.h"   //也是用的这个文件，和c一样

 

int main(void)

{

         void *handle;

         int (*fcn)(int x, int y);

         const char *errmsg;

        

         /* open the library */

         handle = dlopen("libsthc.so", RTLD_NOW);

         if(handle == NULL)

         {

                   fprintf(stderr, "Failed to load libsthc.so: %s\n", dlerror());

                   return 1;

         }

         dlerror();

 

         *(void **)(&fcn) = dlsym(handle, "add");     //ok

         //fcn = dlsym(handle, "add");                        //not ok in c++

         if((errmsg = dlerror()) != NULL)

         {

                   printf("%s\n", errmsg);

                   return 1;

         }

         printf("%d\n", fcn(1, 5));

        

         dlclose(handle);

         return 0;

}