Fw: Using C, C++, Lisp together

i've forwarded this to the appropriate lists.

----- Original Message ----- 
From: "Dunford, Clifton 'Cliff'" <[email protected]>
To: <[email protected]>
Sent: Saturday, December 06, 2003 1:43 PM
Subject: Using C, C++, Lisp together


> Sorry to bother you, but I was hoping you could help me find the anwers to a
> few quesitons. 
> 
> My first queston:
>  I would like to popup-menu at the current cursor location(point). How do I
> do that? Right now it popups at the mouse location in X, and In windows the
> top left corner of the screen.
> 
> Other questions...
> I have some c++ code that I'm using in my feature, I need the info it gets
> to be put into the menu I created at the cursor location. So I'm not sure if
> I'll be calling C from lisp, or lisp from C. I thought maybe I could write a
> C callable code in C++, which will call the C++ function(s).
> A lisp primitive that would call the C code (the wrapper for the C++ code),
> the load lisp menu with the names I need in it. Is there and eaiser way?
> Will this work?
> 
> 
> 
> //.c file
> DEFUN("generate-menu", Fgenerate_menu, 1, UNEVALLED, 1, /*
> Calls a C function parse_menu_wrapper to get the cliffpletions and placed
> them
> in the cliffpletion menu
> */
> 
>       (name))
> {
>   return parse_menu_wrapper(name);
> }
> 
> //not sure what return types I will need, it takes a string and will return
> 1 or more strings
> something like
> .cpp
> extern "C" something parse_menu_wrapper(const* str)
> {
>     return parse_menu(str); //C++ functions
> }
> 
> //C++
> something parse_menu(string str)
> {
>    //read the string
>    //read the parse.dat file and find the string
>   
>    //write the parse_menu.dat file //data for the menu
> 
> }
> 
> Should I be passing some type of stream, I think emacs lisp uses a lstream,
> but not sure how it is used.
> 
> Summary: C++ data stuctures have the names(strings) of what I need, they
> need to be passed to the menus I created at cursor position when needed.