Introduction to Time Handling

Time handling is an essential aspect of programming, especially in the context of finance and algo trading. In C++, there are various libraries and functions that facilitate efficient time handling. Let's take a look at a basic example of time handling in C++:

1#include <iostream>
2#include <ctime>
3
4int main() {
5    // current date/time based on current system
6    time_t now = time(0);
7    
8    // convert now to string form
9    char* dt = ctime(&now);
10    
11    std::cout << "The local date and time is: " << dt << std::endl;
12    
13    // convert now to tm struct for UTC
14    tm* gmtm = gmtime(&now);
15    dt = asctime(gmtm);
16    std::cout << "The UTC date and time is: " << dt << std::endl;
17    
18    return 0;
19}

In this code, we include the header files <iostream> and <ctime> to work with time-related functions. We use the time() function to obtain the current date and time based on the system's clock. We then convert this time_t value to string form using ctime() and output it as the local date and time. Additionally, we convert the time_t value to the tm struct for UTC time using gmtime() and again convert it to string form using asctime(). Finally, we output the UTC date and time.

Try running the code above and observe the output. Notice the difference between the local date and time and the UTC date and time.

Time handling in C++ goes beyond just obtaining the current date and time. It involves functions and libraries to manipulate dates and times, handle time zones, and format dates and times according to specific requirements. We will explore these topics in detail in the upcoming sections of this lesson.

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#include <iostream>

#include <ctime>

​

int main() {

    // current date/time based on current system

    time_t now = time(0);

    // convert now to string form

    char* dt = ctime(&now);

    std::cout << "The local date and time is: " << dt << std::endl;

    // convert now to tm struct for UTC

    tm* gmtm = gmtime(&now);

    dt = asctime(gmtm);

    std::cout << "The UTC date and time is: " << dt << std::endl;

    return 0;

}