Why failed in process of Prolog call C call Prolog?

[Shuai Wang]

Hello gnu-prolog users,

On my 64bit x86 Linux,  I am trying to implement this process.

 

I have two source code, written in C and Prolog. 

In the Prolog code, I have two functions foo and foo1.

So basically inside Prolog function foo, it calls function foo1 through a C wrapper, then after function foo1 finished, it will return through wrapper back to foo

it is something like :

---------------------------------------------------

           Prolog                |         C 

---------------------------------------------------                                

         foo      ----- call ---- >  foo1_wrapper       normal             

         foo1    <-----call -----   foo1_wrapper       normal

         foo1   -------return---> foo1_wrapper       normal

         foo     <-----return----   foo1_wrapper       fail!

The problem is that, it can never return back to function foo after foo1_wrapper returns..

I have done several test(printf, write, valgrind and others...), and I am pretty sure that foo1 returns right value, and foo1_wrapper returns foo1's return value as well.

I am really confused right now, I should be able to look into the details, however, I just don't know which way to go...

Has anyone have certain problems like this...?

Best Regards,

Shuai