dereferencing a void pointer

I wrote the following routine to put an address into reg.r7 and then realized I needed not the address in reg.r7 but the value pointed to by the address. I'm trying to derefence this address but I'm stumped. What I coded still just puts the address into reg.r7

Here is my function:

Code:

---

long convertDate(const void *date1)
{
  ProcessControl& control = getControlArea();
  TPF_regs regs;

  if(date1 !=0)
  {
      regs.r7 = *(long *)date1;
      control.input.location = DatWk::FIRST_R7;
  }
  UA80(&regs);
  return regs.r1;
}

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i don't think :: is a c operator :)

Maybe *date1 is an address?

:: is not the issue and works fine. The value in date1 is an address as I have passed by reference. Using the debugger I looked at the value in the storage location at the address in date1, it does indeed have the value which I want placed into regs.r7. Therefore, I do need to dereference date1. I know that since I passed a void pointer I need to tell the function what type this is a pointer to by using the type cast. Just for testing purposes I am testing the function with a long so I have type cast this as a long pointer and then tried to dereference... *(long *). I thought that would work but I continue to get the value in date1 instead of the data to which date1 points.

Try this.

Code:

---

long convertDate(const void **date1)
{
  ProcessControl& control = getControlArea();
  TPF_regs regs;

  if(date1 !=0)
  {
      regs.r7 = *(long *) *date1;
      control.input.location = DatWk::FIRST_R7;
  }
  UA80(®s);
  return regs.r1;
}

---

my code was actually correct. I was doing a 'duh' on my build. it was actually my build that wasn't correct.

>>:: is not the issue and works fine.
As already said, :: is not a C operator, but it is C++. We have a seperate forum for C++ Q&A.

and it still doesn't matter as it wasn't the question. the question was concerning dereferencing which is C.

Quote:

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Originally posted by cricket
and it still doesn't matter as it wasn't the question. the question was concerning dereferencing which is C.

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No it isn't. Pay attention.

:: is C++, as such, your entire program is now a C++ program. You cannot have one line be C++ and another be "just C". If you have one line C++, the compiler treats the entire program as C++. (This is simplifying a bit, and there is a way to force the issue, but in your case, it doesn't apply even remotely.)

Quzah.