dlsym broken in glibc (2.2.5)

[Felix Gaehtgens]

Hi everybody,

It seems that under Linux (glibc2.2.5), the libdl is just plainly
*broken*. I've attached a very simple C program that should give me the
address of the function "testfunc". Under Solaris (8), it works. However
under Linux (RedHat 7.3) it doesn't. Am I doing something wrong, or is
this a real bug?

Regards,

- Felix


 Under Solaris, I get:

 > gcc symtest.c -o symtest -ldl
 > ./symtest
 Function pointer: 1075c
 >

 Under Linux I get:

 > gcc symtest.c -o symtest -ldl
 > ./symtest
 dlym failed: ./symtest: undefined symbol: testfunc
 >

Here is the simple program:

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

main()
{
  void *func;
  void *handle = dlopen (0, RTLD_GLOBAL|RTLD_LAZY);
  if (!handle) {
    printf ("dlopen failed: %s\n", dlerror());
    exit (-1);
  }
  func = dlsym (handle, "testfunc");
  if (func) {
    printf ("Function pointer: %x\n", func);
  } else {
    printf ("dlsym failed: %s\n", dlerror());
    exit (-1);
  }
}


void testfunc()
{
}



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