call a published native functions with pointers

( using %p as format , it's an alphanumeric value that can't be used in espression string )

What version (e.g. v10.x.y.z) of MicroStation, or other product, are you using?

Alessandro Trebbi said:

I have published a native function

Please show your code.

Your tag MDL is confusing.  In which DLL is the 'native function' supplied?  Why do you want to invoke your function in a C expression?

it's a plugin system, i have an mdl application that registers as plugin to another mdl application (both native): child's functions are published and then called by parent app 

microstation is not the last release, was there a bug that has been fixed ?

Jon Summers said:

What version (e.g. v10.x.y.z) of MicroStation, or other product, are you using?

Alessandro Trebbi said:

microstation is not the last release

What does that mean?

Alessandro Trebbi said:

i have an mdl application that registers as plugin to another mdl application (both native)

If you're building DLLs for MicroStation CONNECT, then don't use 'MDL' because MDL is a V8-era technology.  You have two Windows DLLs.  One DLL can call exported functions in another DLL.  You don't need to 'publish' pointers to MicroStation C expressions.

Read about Windows DLL technology on a Microsoft web site.

Ok i know, but my problem is simply that i can't find a reliable way to pass parameters such as pointers to a function called through mdlCExpression_getValue() ; is it a Microstation bug or did i do something wrong ?

this is the function

typedef int fPrimaDiInserimentoElemento(
  MSElementDescrH,
  CfgFeature *
);

i publish the function :

mdlCExpression_publishFunction (funzioniPubbliche, "myfunction", "PP",
    mdlCExpression_getType (TYPECODE_LONG), primaDiInserimentoElemento);

and this is the expression i'm using for mdlCExpression_getValue()

sprintf(espressione, "myfunction(%lld,%lld)",
featureCorrente.plugin,
(long long)elemDPP,
(long long)&featureCorrente);

the pointers are non valid and dll crashes

sorry this is the code to build expression ( the relevant thing is how i should write the 2 pointers )

sprintf(espressione, "myfunction(%lld,%lld)",
(long long)elemDPP,
(long long)&featureCorrente);

Alessandro Trebbi said:

i publish the function :

Please post all relevant code!  For example, where do you initialise funzioniPubbliche?

Alessandro Trebbi said:

mdlCExpression_getType (TYPECODE_LONG)

If you're publishing pointers, shouldn't that be mdlCExpression_getType (TYPECODE_POINTER)?

that parameter is related to returned value, that is an int, so should be corrected

i have found another couple of functions for expressions,

mdlCExpression_publishTrustedFunction , mdlCExpression_restrictedGetValue

but i have the same problem

and this is "funzioniPubbliche" :

SymbolSet *funzioniPubbliche;

funzioniPubbliche = mdlCExpression_initializeSet(VISIBILITY_CALCULATOR, 0, TRUE);

Alessandro Trebbi said:

mdlCExpression_publishFunction (funzioniPubbliche, "myfunction", "PP",
    mdlCExpression_getType (TYPECODE_LONG), primaDiInserimentoElemento);

The argument "PP" informs mdlCExpression_publishFunction that your function takes two pointers.

However, MSElementDescrH is a pointer-to-pointer (MSElementDescr**).  I don't think that mdlCExpression_publishFunction comprehends pointer-to-pointer.

Alessandro Trebbi said:

i can't find a reliable way to pass parameters such as pointers to a function called through mdlCExpression_getValue()

I still don't understand why you want to use that 20^th century technology.  Where will you use mdlCExpression_getValue()?

• If your point of use is in C++ code that doesn't make sense: you can simply call a public function in your DLL directly
• If your point of use is in a VBA macro, then the same applies if your function is exported from your DLL.  This article may help

I have printed values that i'm trying to pass and values I read in the called function

primaDiInserimentoElemento(359481202760,140722086683472)
primaDiInserimentoElemento(-1296050104,1778197328)

the values are completely different, i suppose that the values I read are truncated to 32b