Hi,

In your first example, the thread that executes `scm_test ()' is not in Guile mode (see `scm_with_guile'), hence the segfault I suppose.

In your second example, I suspect you have two initializations going in parallel.  I'd rather first call `scm_init_guile ()' and then call `guile_exec_thread ()'.  Can you tell us whether that fixes the problem?

Thanks,
Ludovic.

Hi

Of course, the simplest sample code that refuses to run is the following:
#include <libguile.h>
void* scm_test (void* l){
  SCM_TICK;
  scm_c_eval_string("(write (+ 6 5)) (newline)");
}

int main(int argc, char** argv){
  pthread_t blah;
  scm_init_guile();
  pthread_create(&blah, 0,scm_test,0);
  while(1)
    {
      SCM_TICK;
      scm_c_primitive_load("test.scm");
    }
}
This is running on Kubuntu GNU/Linux, here's the output of uname -a:
Linux zero-desktop 2.6.20-16-generic #2 SMP Thu Jun 7 20:19:32 UTC 2007 i686 GNU/Linux
Interestingly, the above sample code has a different problem, namely:
./a.out:
Symbol `scm_i_thread_key' has different size in shared object, consider re-linking
Segmentatiefout (core dumped)

The above might be a specific problem with my guile installation.

The other code with its amount of thread-safety issues (i.e. my original program with some guile additions), has a rather large amount of non-guile related code in it, so I'll omit that in the sample code for now, but, condensed, it'd come down to roughly:


void* guile_main(void* arglet){
  scm_shell(0,0);
}

void* run_guile(void* func){
  scm_with_guile(func,0);
}

pthread_t guile_exec_thread(void* func){
  pthread_t thread;
  pthread_create(&thread,NULL,run_guile,func);
}


int
main (int argc, char **argv)
{
  misc initialization
  guile_exec_thread(guile_main);
  scm_init_guile();
  while (1)
    {
      SCM_TICK;
      the body of a game's drawing loop (uses loads of OpenGL and other non-guile calls)
      scm_c_primitive_load("test.scm");
      sleep until the next frame
    }
  return 0;
}

I'll provide more information if necessary and for now, I'll recompile guile to see if that would fix my first problem.

Thanks for taking the time to discuss this.

Just to clarify, the scm_* functions are called in a function called with scm_with_guile, so the threads calling scm_* functions are in guile mode.