gmtime() Function in C

The gmtime() function in C takes a pointer to type t_time value which represents type in seconds and converts it to struct tm. In this article, we will learn gmtime() Function in the C programming language.

The struct tm type can hold the individual components of time in UTC(Universal Time Coordinated) or GMT time (i.e., the time in the GMT timezone) time zones. The C gmtime() function is defined in <ctime> header file.

Syntax of gmtime()

tm* gmtime ( const time_t* current_time )

• The hours can be accessed using tm_hour
• The minutes can be accessed using tm_min
• The seconds can be accessed using tm_sec

Parameters

• current_time: It specifies a pointer to a time_t object.

Return Value

• On Success, returns a pointer to a tm object.
• Otherwise, the Null pointer is returned.

Examples of gmtime()

Example 1

C

// C program to illustrate the gmtime() function
#include <stdio.h>
#include <time.h>
#define CST (+8)
#define IND (-5)

int main()
{

    // object
    time_t current_time;

    // pointer
    struct tm* ptime;

    // use time function
    time(&current_time);

    // gets the current-time
    ptime = gmtime(&current_time);

    // print the current time
    printf("Current time:\n");

    printf("Beijing ( China ):%2d:%02d:%02d\n",
           (ptime->tm_hour + CST) % 24, ptime->tm_min,
           ptime->tm_sec);

    printf("Delhi ( India ):%2d:%02d:%02d\n",
           (ptime->tm_hour + IND) % 24, ptime->tm_min,
           ptime->tm_sec);
    return 0;
}

Output

Current time:
Beijing ( China ):20:00:04
Delhi ( India ): 7:00:04

Example 2

C

// C++ program to illustrate the
// gmtime() function
#include <stdio.h>
#include <time.h>
#define UTC (0)
#define ART (-3)

int main()
{
      // object
    time_t current_time;

      // pointer
    struct tm* ptime;

      // use time function
    time(&current_time);

      // print the current time
    ptime = gmtime(&current_time);
    printf("Current time:\n");
    printf("Monrovia ( Liberia ) :%2d:%02d:%02d\n",
        (ptime->tm_hour + UTC) % 24, ptime->tm_min, ptime->tm_sec);

    printf("Buenos Aires ( Argentina ) :%2d:%02d:%02d\n",
        (ptime->tm_hour + ART) % 24, ptime->tm_min, ptime->tm_sec);
    return 0;
}

Output

Current time:
Monrovia ( Liberia ) :11:45:36
Buenos Aires ( Argentina ) : 8:45:36