How Can I Define C functions to use VB Callback

How do i define functions in C so that vb is able to pass through a function address (using the AddressOf function in VB6) adn then what whould be the code in C to call that function address

thanks in advance

a VB funciton that should be called must be declared in the main module:

Code:

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public function MyCallback(i as Long, j as Long) as Long

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can be passed to a function in C as follows:

PHP Code:

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// define the type of the function
typedef long (__stdcall* VBCB)(long, long);

// then the function that receives the address:
void __stdcall Func(long i, VBCB pVbFunc)
{
  // call the function
  long j = pVbFunc(i, i+1);
} 


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and the remaining Vb code:

Code:

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private declare sub Func lib "thedll" (i as long, pFunc as long)

'call it
Func 34 AddressOf(MyCallback)
'maybe you need to add "" to the function name

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MISTAKE!!!

Code:

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public function MyCallback(i as Long, j as Long) as Long
'needs to be
public function MyCallback(byval i as Long, byval j as Long) as Long

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or you end up with vb.exe producing an access violation :)

Code:

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private declare sub Func lib "thedll" (i as long, pFunc as long)
'needs to be
private declare sub Func lib "thedll" (byval i as long, byval pFunc as long)

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Thanks for that. It works great