Help Converting C Header

[Andrew Lindsay]

Hello,

I am trying to convert a C Header, but have come a little bit unstuck.

Here is the sample driver program.

int main()
{
	void *render = zg_create(ZG_RENDER);
	
	void *scene = zg_create(ZG_SCENE);
	zg_render_add(render, scene);
	
	void *node = zg_create(ZG_NODE);
	zg_scene_root(scene, node);
	
	void *light = zg_create(ZG_LIGHT);
	zg_node_add(node, light);

	void *poly = zg_create(ZG_POLYGON);
	zg_node_add(node, poly);
	
	void *vert = zg_create(ZG_VERTEX);
	void *norm= zg_create(ZG_VERTEX);
	zg_polygon_vertex(poly, vert);
	zg_polygon_vertexnormal(poly, norm);
	zg_polygon_color(poly, 0, 0, 0.8, 1.0);
	zg_polygon_type(poly, "triangles");
	
	zg_vertex_sphere(vert, norm, 150, 5);
	
	zg_render_show(render);
	
	return 0;
}

The header that I am having 'issues' with is as follows.

DLL_API const char* zg_get_error();
// A API function usually returns 0 or NULL to indicate error and this function may be called to get the error message.

DLL_API void* zg_create(ZG_TYPE type);
// Creates and returns a ZeGraph object.

DLL_API int zg_delete(void *object);
// A ZeGraph object must be deleted safely using this function.

My conversion of these headers is as follows:

DECLARE Function zg_get_error LIB "zeGraph.DLL" Alias "zg_get_error" () as dword
'// A API function usually returns 0 or NULL to indicate error and this function may be called to get the error message.

DECLARE Function zg_create LIB "zeGraph.DLL" Alias "zg_create" (zgType as DWORD) as DWORD
'// Creates and returns a ZeGraph object.

DECLARE Function zg_delete LIB "zeGraph.DLL" Alias "zg_delete" (Object as DWORD) as DWORD
'// A ZeGraph object must be deleted safely using this function.

Do these conversions look correct, also, for the first one, how do I use the string that is returned by the function?

Regards

Andrew

------------------
--------------
andrew dot lindsay at westnet dot com dot au

[José Roca]

DECLARE Function zg_get_error LIB "zeGraph.DLL" Alias "zg_get_error" () as ASCIIZ PTR

DECLARE Function zg_create LIB "zeGraph.DLL" Alias "zg_create" (BYVAL zgType as DWORD) as DWORD

DECLARE Function zg_delete LIB "zeGraph.DLL" Alias "zg_delete" (BYVAL Object as DWORD) as DWORD

> how do I use the string that is returned by the function?
With the new declaration:

DIM szError AS ASCIIZ PTR
szError = zg_get_error()
MSGBOX @szError