What is atoi equivalent for 64bit integer(uint64_t) in C that works on both Unix and Windows?

Question

I\'m trying to convert 64bit integer string to integer, but I don\'t know which one to use.

Answer 1

You've tagged this question c++, so I'm assuming you might be interested in C++ solutions too. You can do this using boost::lexical_cast or std::istringstream if boost isn't available to you:

#include 
#include 
#include 
#include 
#include 

int main() {
  uint64_t test;
  test = boost::lexical_cast("594348534879");

  // or
  std::istringstream ss("48543954385");
  if (!(ss >> test))
    std::cout << "failed" << std::endl;
}

Both styles work on Windows and Linux (and others).

In C++11 there's also functions that operate on std::string, including std::stoull which you can use:

#include 

int main() {
  const std::string str="594348534879";
  unsigned long long v = std::stoull(str);
}