cout << (_int64 object)

using VC++ 6.0 compiler, how to use cout to display an _int64 object. Is there a solution with that compiler?

Code:

---

#include <iostream>
using namespace std;

int main()
{
  _int64 x;
  cout << x;

  return 0;
}

---

error message

Code:

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error C2593: 'operator <<' is ambiguous

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Use a better compiler? Even then I don't know if that would suppport a _int64

It works for me on VC 6.0. You may need to install a service pack or get a fix from dinkumware or download a different version of the standard library (I think I'm using 3.08 which is not the one that ships with VC 6).

BTW, I thought it was supposed to be __int64, although _int64 also works for me.

I do get that error if I use <iostream.h>, make sure you are using <iostream>.

I have SP5 installed. overloading the << operator works.

Code:

---

ostream& operator<<(ostream& out, _int64 n)
{
        printf("%I64d", n);
        return out;
}

---

Isn't it better to avoid mixing printf and cout?

Code:

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ostream& operator<< (ostream &o, _int64 n)
{
  char buffer [ sizeof n * CHAR_BIT + 1 ]; /* plenty of space */
  sprintf(buffer, "%I64d", n);
  return o << buffer;
}

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Quote:

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Originally Posted by Dave_Sinkula

Isn't it better to avoid mixing

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normally -- yes. sprintf() and printf() both use the same routines to parse the format specification string, so it doesn't really matter which one of those are used. and cout and printf() call the same low-level printing functions in some implementations, such as VC++ 6.0 where they both call with win32 api function WriteFile().


I suppose some compilers/platforms may have some serious objects about mixing iostream library functions with standard C file functions, but I have never had any problems with any Microsoft compilers (yet!).