1  #include <dlfcn.h>
       2  #include <error.h>
       3  #include <mcheck.h>
       4  #include <stdio.h>
       5  #include <stdlib.h>
       6  
       7  int
       8  main (void)
       9  {
      10    void *su[5];
      11    void *h;
      12    int n;
      13  
      14    mtrace ();
      15  
      16    if ((su[0] = dlopen ("testobj1.so", RTLD_GLOBAL | RTLD_NOW)) == NULL
      17        || (su[1] = dlopen ("testobj2.so", RTLD_GLOBAL | RTLD_NOW)) == NULL
      18        || (su[2] = dlopen ("testobj3.so", RTLD_GLOBAL | RTLD_NOW)) == NULL
      19        || (su[3] = dlopen ("testobj4.so", RTLD_GLOBAL | RTLD_NOW)) == NULL
      20        || (su[4] = dlopen ("testobj5.so", RTLD_GLOBAL | RTLD_NOW)) == NULL)
      21      error (EXIT_FAILURE, 0, "failed to load shared object: %s", dlerror ());
      22  
      23    h = dlopen ("failobj.so", RTLD_GLOBAL | RTLD_NOW);
      24  
      25    printf ("h = %p, %s\n", h, h == NULL ? "ok" : "fail");
      26  
      27    for (n = 0; n < 5; ++n)
      28      if (dlclose (su[n]) != 0)
      29        {
      30  	printf ("failed to unload su[%d]: %s\n", n, dlerror ());
      31  	exit (EXIT_FAILURE);
      32        }
      33  
      34    return h != NULL;
      35  }
      36  
      37  extern int foo (int a);
      38  int
      39  foo (int a)
      40  {
      41    return 10;
      42  }