C / C++ / MFC

#include <stdio.h>
typedef void (*PFN_YOURFUNCTION)(void);

void TestFunction1()
{
   printf( "TestFunction1\n" );
}

void TestFunction2()
{
   printf( "TestFunction2\n" );
}

int main()
{
   PFN_YOURFUNCTION a_pfnFunction = NULL;
   a_pfnFunction = TestFunction1; // Set it to TestFunction1
   a_pfnFunction(); // Call pointed at function.
   a_pfnFunction = TestFunction2; // Set it to TestFunction2
   a_pfnFunction(); // Call pointed at function.
   return 0;
}

TestFunction1
TestFunction2

<br />
// MEMPTR is a variable type pointing to a location in memory<br />
<br />
struct FUNCSTRUCT { // Function calling structure<br />
      MEMPTR *FunctPtr; // Function pointer<br />
      int VarCount; // Number of Variables<br />
      MEMPTR *VarPtr[255]; // Varaible pointers<br />
      int VarSize[255]; // Varaible byte sizes<br />
}<br />
<br />
MEMPTR CallFunc(FUNCSTRUCT *FunctData); // The powerful function that does the call<br />
<br />
int TheRealFunc(int Argument){ // Declare normal function<br />
      return Argument;<br />
}<br />
<br />
int main(){<br />
      FUNCSTRUCT FuncData; // Declare function type<br />
      int Value = 1; // Give a value to send as argument<br />
<br />
      FuncData.FunctPtr = TheRealFunc; // Point to normal function<br />
      FuncData.VarCount = 1; // Number of values to send as arguments<br />
      FuncData.VarPtr[0] = Value; // Point to the value<br />
      FuncData.VarSize[0] = 2; // Byte size of an integer value<br />
<br />
      return CallFunc(&FuncData); // Call the function<br />
}<br />

int TheRealFunc(const char* argument)
{
    // agument is an integer so lets convert
    int i = atoi(argument);

    // blah blah blah
}

int TheRealFunc(int a1, int a2, float a3)
{
    // blah blah blah
}

int TheRealFuncWrapper(const char* argument1, const char* argument2, const char* argument3)
{
    // convert the parameters
    int a1 = atoi(argument1);
    int a2 = atoi(argument2);
    float a3 = atof(argument3);

    return TheRealFunc(a1, a2, a3);
}

bool g_alreadyInFuncA = false;

void funcA()
{
  if (g_alreadyInFuncA)
  {
    error? return early? crash?
  }

  g_alreadyInFuncA = true;

  blah 
  blah
  MessagePump...
  blah
  g_alreadyInFuncA = false;
}

void OnMyMessage()
{
 funcA()
}