Passing data

Hello,

Earlier today, I asked about how to allocate a big memory location. Thanks all! Now I have another problem, please help.
I have a short program like this:

int main(void) {
CallFunction (datapassing1);
CallFunction (datapassing2);
.
.
return 0;
}

Where datapassing1 and datapassing2 are short programs that need a memory space of about 4kb to do some cratch work. I don't know how to pass the data, allocate the memory location for this datapassing. Anyone has any idea, please give me some advice. I really appreciate.

Quote:

---

Originally posted by vnrabbit
Where datapassing1 and datapassing2 are short programs that need a memory space of about 4kb to do some cratch work

---

Do you mean functions?
The fastest way would be to send the pointer to the data (only pass 4 bytes instead of 4k, or whatever).

Code:

---

void datapassing1(int* Data)
{
  ... //Do whatever
}

void datapassing2(int* Data)
{
  ... //Do whatever
}

int main(void)
{
  int* Data; //Assume your data are integers
  Data = new int[SizeOfData]; //Allocate memory
  if(Data == NULL) return 0; //Check if allocation was successful

  ...

  CallFunction (datapassing1(Data));
  CallFunction (datapassing2(Data));

  delete[] Data; //Deallocate the memory
  return 0;
}

---

> Data = new int[SizeOfData]; //Allocate memory

Slight correction. The above code is C++, not C. You'd want:

Data = malloc( sizeof(int) * number_to_allocate ) );

The same goes for the 'delete' call.

Quzah.

Thanks guys.

However, I can't change the datapassing1 and datapassing2 functions on the way I call them. Maybe I didnt explain my question clearly. When I call in the CallFunction() in Main, I then need to allocate a memory location about 4kb for datapassing1 and datapassing2 to do their stuff on this 4kb memory location.

Code:

---

void myFunction( void * data )
{
    /* do something */
}

int main( void )
{
    /*
        Allocate 4 KB of data.
    */
    void *dataBlock;
    dataBlock = malloc( 4096 );

    myFunction( dataBlock );

    return 0;
}

---

There's one way to allocate a 4KB block of data for use elsewhere. Naturally it's better to actually allocate specific types, but if you just want a solid 4K block of memory allocated for you, that'd do it.

You could then dice that up or do whatever you intend with it.

Quzah.