How to get current timestamp in milliseconds since 1970 just the way Java gets

use <sys/time.h>

struct timeval tp;
gettimeofday(&tp, NULL);
long int ms = tp.tv_sec * 1000 + tp.tv_usec / 1000;

refer this.

If you have access to the C++ 11 libraries, check out the std::chrono library. You can use it to get the milliseconds since the Unix Epoch like this:

#include <chrono>

// ...

using namespace std::chrono;
milliseconds ms = duration_cast< milliseconds >(
    system_clock::now().time_since_epoch()
);

Since C++11 you can use std::chrono:

• get current system time: std::chrono::system_clock::now()
• get time since epoch: .time_since_epoch()
• translate the underlying unit to milliseconds: duration_cast<milliseconds>(d)
• translate std::chrono::milliseconds to integer (uint64_t to avoid overflow)

#include <chrono>
#include <cstdint>
#include <iostream>

uint64_t timeSinceEpochMillisec() {
  using namespace std::chrono;
  return duration_cast<milliseconds>(system_clock::now().time_since_epoch()).count();
}

int main() {
  std::cout << timeSinceEpochMillisec() << std::endl;
  return 0;
}