printing bytes from memory (NOOB question)

**MishaMish** · 01-25-2011

Hi,
I'm new to C++ so please help me...

I have an address in memory, and I want to print out 100 bytes from this address on.
one by one in HEX.

How do I do that?

Thanks

**User Name:** · 01-25-2011

You'll probably cause your program to crash. But, if you want to try, show us what you have and we'll go from there.

**MishaMish** · 01-25-2011

ok...
The pointer to the data is in the second cell in a given array (parameter to my function). and I take it like this:

Code:

void myFunction(void** const args)
{
  DWORD32* datapointer = (DWORD32*)(args[1]);
  // if I print out this datapointer I get good address, I checked with some memview.

  for (int i=0; i<100; i++)
  {
    int val = (int)(*datapointer);  // the values that I get in val, are not what I expect...
    datapointer++;
  }
}

All this code is trying to everything with int... and I want byte by byte...
no idea how to do that...

seems that I'm way off...
Thanks for your help!

**User Name:** · 01-25-2011

It would be easier to think about if you had the pointer passed as a separate arg.

Code:

void myFunction(DWORD32 *datapointer)
{
  // use datapointer
}

It would also be a lot easier if you accessed datapointer as an array of DWORD32s rather than doing pointer arithmetic. Pointer arithmetic can be confusing even for the best of us.

Code:

void myFunction(DWORD32 *datapointer)
{
  for (int i=0; i<100; i++)
  {
    DWORD32 val = datapointer[i];
    // print val
  }
}

But remeber that DWORDs are 4 bytes, so you could use uint8_t, a type defined in stdint.h.

Code:

#include <stdint.h> // required for uint8_t

void myFunction(uint8_t *datapointer)
{
  for (int i=0; i<100; i++)
  {
    uint8_t val = datapointer[i];
    cout << (unsigned int)val;
  }
}

**MishaMish** · 01-25-2011

Thanks! it was VERY helpful!

now maybe we can go on with the last thing that I have here...

On this array I have 4 bytes that I don't need (just skip them)
After that, I have a string (terminated by 0), I need to print it out.
after that, another 4 useless bytes.
and after that, an int that I need to print too...

please please....
THANKS!

**MishaMish** · 01-25-2011

bump

**MishaMish** · 01-26-2011

comon if this is soooo easy, can someone post a short code that does that?
I'll pay $1000... well ok not.. but I'll be thankful

**Salem** · 01-26-2011

Yeah, so easy, we're waiting for you to make a stab at it.

You've already got all the components you need, all it now needs from you is a bit of application to the problem.

Thread: printing bytes from memory (NOOB question)

Thread Tools

Search Thread

Display

printing bytes from memory (NOOB question)

Similar Threads

Mutex and Shared Memory Segment Questions.

Problems with shared memory shmdt() shmctl()

Another Question...memory allocation

Question regarding Memory Leak

Question regarding constructors and memory.....