1  /* Copyright (C) 2001-2023 Free Software Foundation, Inc.
       2     This file is part of the GNU C Library.
       3  
       4     The GNU C Library is free software; you can redistribute it and/or
       5     modify it under the terms of the GNU Lesser General Public
       6     License as published by the Free Software Foundation; either
       7     version 2.1 of the License, or (at your option) any later version.
       8  
       9     The GNU C Library is distributed in the hope that it will be useful,
      10     but WITHOUT ANY WARRANTY; without even the implied warranty of
      11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      12     Lesser General Public License for more details.
      13  
      14     You should have received a copy of the GNU Lesser General Public
      15     License along with the GNU C Library; if not, see
      16     <https://www.gnu.org/licenses/>.  */
      17  
      18  #include <dlfcn.h>
      19  #include <stdio.h>
      20  #include <stdlib.h>
      21  
      22  
      23  int
      24  main (void)
      25  {
      26    const char fname[] = "modatexit.so";
      27    void *h;
      28    void (*fp) (void *);
      29    int v = 0;
      30  
      31    h = dlopen (fname, RTLD_NOW);
      32    if (h == NULL)
      33      {
      34        printf ("cannot open \"%s\": %s\n", fname, dlerror ());
      35        exit (1);
      36      }
      37  
      38    fp = dlsym (h, "foo");
      39    if (fp == NULL)
      40      {
      41        printf ("cannot find \"foo\": %s\n", dlerror ());
      42        exit (1);
      43      }
      44  
      45    fp (&v);
      46  
      47    if (dlclose (h) != 0)
      48      {
      49        printf ("cannot close \"%s\": %s\n", fname, dlerror ());
      50        exit (1);
      51      }
      52  
      53    if (v != 1)
      54      {
      55        puts ("module unload didn't change `v'");
      56        exit (1);
      57      }
      58  
      59    puts ("finishing now");
      60  
      61    return 0;
      62  }